United States
Environmental Protection
Agency
Office of Research and
Development (8701R)
Washington DC 20460
EPA/600/R-00/055
July 2000
www.epa.gov/ncerqa
£EPA
STAR Graduate Fellowship
Conference 2000 Abstracts
July 9-12, 2000 Washington DC
National Center for Environmental Research
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
PRO**'*
JUN -7 2000
OFFICE OF
RESEARCH AND DEVELOPMENT
Dear STAR Graduate Fellow:
I am pleased to welcome you to the Fifth Annual Conference of the Science to Achieve
Results (STAR) Graduate Fellows. We are excited about this year's conference. We are
tackling the biggest questions ever - literally whether humanity can continue to survive on
Planet Earth. We have put together dynamic panels with excellent speakers from diverse
perspectives who we hope will stimulate you to think of these questions in new ways.
The theme of this year's conference is "On Top of the World: The Environmental Effects
of Human Ascendancy." It is incontestable that humans have had an enormous impact on the
planet. Billions of words have been written by environmentalists to explain and anticipate the
size of the footprint that mankind will leave and the number of species and systems that will
suffer from our presence. At the same time, it is far from universally agreed that we pose any
significant threat at all to the balance of nature.
Besides being specialists in your particular areas, you are all human beings and you all
feel passionate about some question or questions about our place in the world. We have
attempted in this conference to provide five focus groups that will enable you to debate the
issues that interest you professionally and that fire you personally. They are very big questions
and we won't answer them here, but we know that within each focus area there are problems that
you can attack and for which you can recommend solutions. The five focus areas are:
** Water Wars and Food Fights: Is There Enough to Go Around?
** Just Gotta Have It: The Age of Consumption
** Cockroaches and Poison Ivy: How Much Diversity Do We Really Need?
*" Limiting Our Own Growth: The Mark of Maturity or Sheer Madness?
** The Sorcerer's Apprentice: Global Impacts of Human Technological Development
To devise reasonable recommendations you will all have to challenge the assumptions of
the past, particularly those that we have used habitually to justify our sense of planetary manifest
destiny. You will also need to hear and respect the voices of people whose opinions and points
of view are wildly different from your own.
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On behalf of EPA, I am proud that we have played a role in nurturing your educations
and I hope as you all go on to your successful careers, you will carry with you some lasting
lessons and pleasant memories of your time as a STAR Fellow. Best of luck and enjoy the
conference!
Sincerely,
Norine E. Noonan, Ph.D.
Assistant Administrator
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
NATIONAL CENTER FOR ENVIRONMENTAL RESEARCH
AND QUALITY ASSURANCE
WASHINGTON, DC 20460
JUN - 7 2000
OFFICE OF
RESEARCH AND DEVELOPMENT
INTRODUCTION
Welcome to the Fifth Annual EPA STAR Graduate Fellows Conference. My staff and I
have read your abstracts and I am delighted to see such breadth and depth of expertise and such
compelling environmental insights. I am honored to be a small part of your graduate education
and am confident that you will eventually play an important role in solving the world's
environmental problems.
The purpose of the National Center for Environmental Research (NCER) is to provide
answers to the persistent and emerging problems that vex environmental decision-makers. As
you have no doubt begun to realize, these problems are not straight forward and will not be
solved by single individuals working alone. To solve the problems of tomorrow will require the
efforts of environmental professionals who are not only exquisitely trained in their disciplines,
but who are skilled communicators who can listen as well as speak and write, and who are
equally comfortable and effective dealing with those inside and outside their chosen fields. We
will need social, economic and behavioral scientists who can work productively with physical
and life scientists, engineers and technologists. All these professionals must be able to interact
constructively with policy experts, politicians, advocacy groups, and individual citizens. We
must be able to work together to find solutions not just for Americans or our allies, or even just
for humanity, but for the entire planet and every living thing on it.
I believe that you, the "Millennium Class" of STAR Fellows are a great start toward that
goal and I applaud you. Enjoy the conference!
Sincerely,
Peter W. Preuss, Ph.D.
Director, National Center
for Environmental Research
R*cycl»d/R«cycl*ble • Printed with Vegetable OH Based Into or 100% Recycled Paper (40% Poetconsumer}
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STAR Graduate Fellowship Conference
CONTENTS
Behavioral Defenses Against Ultraviolet Radiation by the Green Sea Urchin
Strongylocentrotus Droebachiensis
Nikki L. Adams 1
Wastewater Irrigation and Elevated Groundwater Chloride Concentrations in Israel
and Palestine
Jeff Albert 3
Seed Banks and Prescribed Burns: Factors Affecting Successful Control of French Broom
and Restoration of Native Communities in Coastal California Grasslands
Janice M. Alexander 4
Sedimentation, Mercury Contamination, and Clay Mineralogy of the Dorena Lake
Watershed, Western Oregon
Rebecca Ambers 5
Developmental Effects of Complex Pollutant Mixtures: Organophosphates, Alkylphenols,
and Larval Salmonid Ossification
Erin L. Amweg 6
Late Holocene Forest History in the Coto Brus Region of Costa Rica
Kevin J. Anchukaitis 7
The Road to Ludlow: Work, Environment, and Industrialization in Southern
Colorado, 1870-1915
Thomas G. Andrews 8
Causes and Consequences of Individual and Geographical Variation in Body Condition
and Reproductive Success
Daniel R. Ardia 9
Management of Hawaiian Precious Corals Using Molecular Genetic Methods
Amy R. Baco-Taylor 10
Optimal Cost-Sharing Mechanisms for Nonpoint Source Pollution Control
Kenneth A. Baerenklau 11
Diversity of Expressed Biodegradation Genes
Corien Bakermans 12
Path Selection by Red Squirrels (Tamiasciurus Hudsonicus) in Logged Forests
in Southeast Alaska
Victoria J. Bakker 14
A New Dimensionless Index for Structural Habitat Complexity
Aaron Bartholomew 15
Impacts of Flow Diversion and Regulation on Successional Processes in Cottonwood
and Willow Dominated Riparian Forests, Verde River, Arizona
Vanessa B. Beauchamp 16
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STAR Graduate Fellowship Conference
Air Pollution and Human Health
Michelle L. Bell 17
Watershed Modeling and Uncertainty Analysis of the Cannonsville Reservoir Basin
Jennifer Benaman 18
Community-Based Natural Resource Management in Mali
Charles E. Benjamin 19
Stability Constants for Mercury Binding with DOC Isolates from the Florida Everglades
Janina M. Benolt 20
Amphibian Dispersal in Fragmented Landscapes
GayleL. Birchfield 21
Intratropieal Migration of a Lowland Parrot: Implications for Conservation
Robin D. Bjork 22
Mechanisms of Phytoremediation and Constructed Wetlands Engineering
Diane L. Bondehagen 24
A Bayesian Probability Network Approach to Predictive Modeling in Support
of Environmental Decision Making
Mark E. Borsuk 25
Estrogen-Regulated Gene Expression in Largemouth Bass (Micropterus Salmoides)
Christopher J. Bowman 27
Community Interactions That Affect Nutrient Dynamics in Salt Marshes: Lessons
for Habitat Restoration
Katharyn E. Boyer 29
Host Fidelity and Apparent Competition in Host-Parasitoid Systems
Chad E. Brassil 31
A Model for Ecosystem Management Through Land-Use Planning: Understanding
the Mosaic of Protection Across Ecological Systems in Florida
Samuel D. Brody . . 32
Phosphorus Dynamics in a Tidal Oligohaline Marsh: Implications of Sulfate
and Tidal Influence
JeannaR. Bryner 33
Nitrogen Cycling in a Shallow Coastal Lagoon: Role of Photochemistry
IshiD. Buffam 34
Documenting Changes in Customary Marine Tenure: A Case Study
of an Outer Island Group in Fiji
Mark A. Calamia 35
Submerged Aquatic Plant Community Dynamics
Robert S. Capers 35
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STAR Graduate Fellowship Conference
An Analysis of Legal and Regulatory Mechanisms to Control Interstate Ozone Transport
Christina C. Caplan 37
Integrating Agricultural Censuses and Satellite-Based Classifications for the Amazon
and Tocantins Basins
Jeffrey A. Cardille 38
Effects of Climate Variation on Subalpine and Coastal Vegetation and Landscapes
Charles T. Carlson 40
Reproductive Success and Conservation Genetics of Humpback Whales
in the North Pacific
Salvatore Cerchio 41
Exposure to Organophosphate Pesticides in a Mexican Agricultural Community
Guadalupe Chapa 42
Analysis of the Impact of Protected Area Establishment on Deforestation
in Caribbean Guatemala
Ted F. Cheeseman 43
Cost Savings From Properly Managing Endangered Species Habitats
Linus Y. Chen 44
Epiphytic Macroinvertebrate Abundance Along a Gradient of Eurasian Water Milfoil:
The Role of Plant Species and Architecture
Kendra S. Cheruvelil 45
The Environmental Fate of Methyl Tert Butyl Ether
Clinton D. Church 46
High Islands and Low: The Biogeography of Fijian Coral Health
Tegan P. Churcher 49
Genetic Consequences of Fragmentation in Fraser Fir Populations
Catherine M. Clark 50
Frugivore Impact on Seed Rain Patterns in a Central African Tropical Forest
Connie J. Clark 51
Genetic Algorithms for Model Development and Process Design in Environmentally-Conscious
Design and Manufacturing
John M. Clayton 52
Development of a Bioindicator of Freshwater Influx to Marine Communities Using
a Salinity-Sensitive Symbiosis in the Temperate Sea Anemone Anthopleura Elegantissima
Risa A. Cohen 53
Effects of Fire Frequency and Red Imported Fire Ants on Native Insects in a Louisiana
Longleaf Pine Savanna
Deanna M. Colby 54
in
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STAR Graduate Fellowship Conference
Biogeographical Comparison of Nutritional Effects of the Toxic Dinoflagellate
Alexandriura Sp. on the Copepod Acartia Hudsonica
Sean P. Colin 55
Critical Body Residues and Ion-Exchange Membranes as Measures of Heavy Metal
Unavailability and Toxicity in Soil
Jason M. Conder 56
Investigating Blue Whale (Balaenoptera Musculus) Population Structure Using Introns
of Conserved Nuclear Genes
Carole A. Conway 57
Partitioning of Ethoxylated Nonionic Surfactants in Water/Non-Aqueous Phase Liquid (NAPL)
Systems: Effects of Surfactant and NAPL Properties
Matthew A. Cowell 58
A Review of Steep Channel Design Methodologies
Joanna C. Crowe 59
Superfund Implementation Analysis: Examining the Program's Unintended Consequences
and Environmental Progress
Dorothy M. Daley 60
Developmental Nearotoxicity of the Pesticide, Chlorpyrifos: Mechanisms and Consequences
KristinaDam 61
Supply Chain Management for Infrastructure Development of Solar Energy
Recharging Stations
Tarsha N. Dargan 63
Collective Environmental Action From an Anthropological Perspective: A Study
of Environmental Movements in the United States
Vinci E. Daro 64
Aqueous Silica in the Environment: Effects on Iron Hydroxide Surface Chemistry
and Implications for Natural and Engineered Systems
Christina C. Davis 66
Using Radar Tomography, Hydraulic Tests, and Tracer Experiments to Characterize
Fractu red-Rock Flow Systems
Frederick D. Day-Lewis 67
Effects of Logging on Understory Plant Diversity in Northern Hardwood Forests
Daniel R. DeJoode 68
Voices From the Mountains: Children's Sense of Place in Northern New Mexico
Victoria L. Derr 69
Ecological Strategies of Bacteria and the Efficiency of Protein Synthesis
Les Dethlefsen 70
Potential Impacts of Transgenic Poplar Cultivation
Stephen P. DiFazio 71
IV
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STAR Graduate Fellowship Conference
Environmental Influences on Insect Flight Performance
Michael E. Dillon 72
Dynamics of Pioneer Forests along the Wisconsin River: Landscape, Local,
and Temporal Factors
MarkD, Dixon 74
The Use of Alfalfa (Medicago Sativa) to Recover Chromium(III) and Chromium(IV)
From Aqueous Solution
Kenneth M. Dokken 75
Analysis of Dermal Exposure to Pesticide Residues
Ed M. Doran 76
Conservation Genetics and Systematics of Sturgeon
Phaedra Doukakis 77
Confirmed Detection of Cyclospora Cayetanesis and Encephalitozoon Intestinalis
in Water Used for Drinking
ScotE. Dowd 78
Early Postnatal Lead Exposure Alters the Gabaergic Modulation of Sustained Attention
Lori L. Driscoll 79
Relationship Between Rates of Ligand-Promoted Dissolution of Hematite and the Iron-Ligand
Surface Structures of Cl to C6 Dicarboxylic Acids
Owen W. Duckworth 81
Prospects and Policies for Residential Thin-Film Photovoltaic Roofing
Richard D. Duke 82
Pathogen Survival in Drinking Water Distribution Systems
Nathaniel K. Dunahee 84
Bacillus Cereus UW85 and Tomato Plants: A Biological Control Model System
Anne K. Dunn 85
Using Conservation Endocrinology to Assess the Risk of Local Extinction: A Case Study
of Malagasy Lemurs
Debra L. Durham 86
Environmental Decay of Pathogens
John H. Easton 87
The Application of Geophysical Investigations to Urban Landforms: A Geophysical
Investigation of the Geologic Setting of Hillview Road Landfill in Danby, NY
Alissa M. Ede 88
The Influence of Membrane Treatment on Bacterial Regrowth Potential in Drinking Water
Isabel C. Escobar 89
The Effects of Human Hunting on Northern Fur Seal (Callorhinus Ursinus) Migration
and Breeding Distributions in the Holocene
Michael Etinier 90
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STAR Graduate Fellowship Conference
Selected Aspects of the Toxicokinetics and Unavailability of Cadmium and Lead
in Animal and Cellular Models
Timothy J. Evans 92
Detection of Nitric Oxide in Mice by Electron Paramagnetic Resonance Techniques
Jesse A. Pecker 93
Barriers to Forest Regeneration on Abandoned Central Amazonian Pastures
Ted R. Feldpausch 94
Analysis and Fate of Sewage-Derived Polar Contaminants in the Marine Environment
Patrick L. Ferguson 96
Environmental Enforcement Choice: Trading Off Equity for Environmental Benefits
Jeremy M. Firestone 97
Nitrogen Removal in Constructed Wetlands: Enhancement of Nitrate Mass Transfer
in the Denitrification Zone
Maia S. Fleming 98
Proximal and Distal Factors in Desert Annual Seed Germination
CJ. Fotheringham 99
Image Use in the Characterization of Field Parameters: Integration of Remote Sensing
With Hydrologic Simulation Modeling
GareyA. Fox 101
Maps of the Future: Multi-Scale Precipitation Modeling and Forecasting
Chris C. Funk 102
Physiological and Biochemical Controls Over Isoprene Emission From Plants
Jennifer L. Funk 103
Toxicity Studies of Chlorpyrifos to Leopard Frog (Rana Pipiens) Embryos
Lia M. Gaizick 104
Laboratory Studies of Tropospheric Ozone Formation: A Novel Technique for Probing
Volatile Organic Hydrocarbon Oxidation
Eva R. Garland 105
Origins and Hybridization of Invasive Saltcedar (Tamarix) Inferred from DNA Sequences
John F. Gaskin 106
Effects of Altered Disturbance Regimes: Levees and Floods
Sarah E. Gergel 107
Effects of Biological-Physical Interactions on Gene Flow in Marine Planktonic Populations
Erica Goetze 109
Understanding Barriers to the Use of Renewable Energy for Remote Electrification
by State Utilities in Thailand
Christopher E. Greacen HO
VI
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STAR Graduate Fellowship Conference
Predicting Mercury Levels in Fish: Use of Water Chemistry, Trophic Ecology,
and Spatial Traits
Ben K. Greenfield Ill
Characterization of Microbial Populations That Produce Trans-Dichloroethene (DCE)
as the Major Product of Tetrachloroethene (PCE) Reductive Dechlorination
Benjamin M. Griffin 112
Evaluation of Semipcrmeable Membrane Devices (SPMDs) and In-Vitro Bioassays
for Groundwater Monitoring at a Former Coal-Gas Facility
Karl E. Gustavson 113
Non-Target Effects of Bt Corn Pollen on the Monarch Butterfly
Laura C. Hansen 114
The Effects of Alternative Prey on a Generalist Predator
Jason P. Harmon 115
Evaluation of Patterns of Land Cover Based on GIS and Fuzzy Set Theory
Thomas B. Harrington, Jr 116
Management Impacts on Positive Feedbacks in Carbon and Nitrogen Cycles of Great
Plains Grasslands
Wylie N. Harris 117
Extratropical Transition of Tropical Cyclones: Climatology, Lifecycle,
and Numerical Simulation
Robert Hart 119
Multiple Stressors and Amphibian Population Declines
Audrey C. Hatch 120
Spectroscopic Characterization of Organic Aerosols
Cindy D. Hauser 121
Interaction Between Grazing and Nutrients as Controls of Macrophyte Biomass
and Community Structure in Shallow Temperate Estuaries
Jennifer A. Hauxwell 122
Edge Effects on Carbon and Nitrogen Cycling in Fragmented Oldgrowth Forests
of the Pacific Northwest
Tom D. Hayes 123
A Thousand Pieces of Paradise: Nature, Property, and Community in the Kickapoo Valley
LynneHeasley 124
Assessing the Use of Genetically Engineered Plants to Remediate Mercury Contaminated Soils
Andrew C. Heaton 125
Accumulation of 4-Nonylphenol (NP) in Short Estuarine Food Chains Potentially
Leading to Endocrine Disruption in Chinook Salmon Fry
Scott A. Hecht 126
VII
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STAR Graduate Fellowship Conference
Characterizing Fire Regimes in Conifer Forest Using Optical and Microwave Remote Sensing
Mary C. Henry 127
Economic Reform, NGOs and Cranes in Russia and China
MelindaK. Herrold 128
Dispersal on Structured Heterogeneous Landscapes
David E. Hiebeler 129
Fish, Forest Plans and Fairness: Creating a Natural Resource Commons
in Southwest Montana
Lorie L. Higgins 130
Drawing of Flexible Chain Polymers in High Pressure CO2
Terry R. Hobbs 131
Evaluation of Hydrologic and Water Quality Benefits of Infiltration-Based Urban
Stormwater Management
Jennifer K. Holman-Dodds 132
A Land Surface Process/Radiobrightness Model for Agricultural Terrain
Brian K. Hornbuckle 133
Relationships Between Ground Water Availability and Riparian Tree Physiological
Condition and Growth
Jonathan L. Horton 134
Biodiversity of Minnesota Caddisflies (Insecta: Trichoptera)
David C. Houghton 136
Improving Pest Management by Understanding Movement Behavior
Cynthia L. Hsu 137
Environmental Antibiotics in Chesapeake Bay Tributaries
Thomas B. Huff 138
Damage to Arachidonic Acid and Plasmid DNA Mediated by Products of MMT Combustion
Rachel A. Jameton 139
Development of the Ascidian, Ciona Savignyi, as a Marine Ecological Indicator Organism
David S. Johnson 140
Rapid Characterization of Long-Term HOC Desorption From Soils and Sediments
by Superheated Water Extraction Techniques
Martin D. Johnson 141
Influence of Biosurfactants on Soil-Aged Organic Contaminant Transport
Stephanie E. Johnson 142
Behavioral and Ecological Interactions of Raptors and Lemurs: A Multiple
Predator-Multiple Prey Approach
Sarah M. Karpanty 143
viii
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STAR Graduate Fellowship Conference
Effects of Fluvial Disturbance and Flow Regulation on Great Plains Riparian Trees
Gabrielle L. Katz 145
Integrating Competition and Predation: Conservation Implications of Multi-Species
Interactions at the Landscape Scale
Todd E. Katzner 146
Induced Sequestration of Phenolic Compounds in Natural Sorbents
Michael Keinath 148
Sediment Entrainment and Stream Benthic Communities: Implications
for Freshwater Bioassessment
Stephen T. Kenworthy 149
Controls on Arsenic Mobility in a Metal-Contaminated Wetland
Nicole E. Keon 150
Microbial Population Dynamics During the Degradation of Complex
Contaminant Mixtures
Eric A. Kern 151
Climate-Mediated Shifts in Hurricane Characteristics: Large-Scale Ecological
Effects on Coral Reefs
Alexander M. Kerr 152
Urban by Nature: Shaping Seattle's Metropolitan Environments, 1880-1970
Matthew W. Klingle 153
Effects of Multiple Environmental Perturbations on Phytoplankton Communities
Jennifer L. Klug 154
Reduction of Herbicides in Wetland Sediments
Theodore P. Klupinski 156
Highland and Lowland Land-Use Among the Q'eqchi'-Maya
Paul D. Kockelman 157
Nature and the Cultural Politics of Difference in Northen New Mexico
Jon Kosek 158
Private Provision of Public Goods: Environmental Improvement Through 'Green'
Electricity Consumption
Matthew J. Kotchen 159
Impacts of the Argentine Ant (Linepithema Humile) on Pollination
Lori J. Lach 160
Negotiating Conservation: Peasants and Forest Conversion in the Buffer Zone
of the Indio-Maiz Reserve, Nicaragua
Anne M. Larson 161
Ecology and Population Regulation of Neotropical Migratory Birds on Hispaniola
Steven C. Latta 163
IX
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STAR Graduate Fellowship Conference
From Yellowstone to Yukon: Combining Science and Advocacy to Shape Public
Opinion and Policy
Suzanne M. Levesque ........................................ 165
Complex Interactions in Estuarine Salt Marsh Communities
David B. Lewis ........................................... 166
Using a Physiologically Based Pharmacokinetic Model for Methyl Tert-Butyl Ether
in Humans to Investigate Variability in Metabolic Enzymes
Amy Collins Licata ......................................... 167
Measuring the Extent and Impact of Biotic Invasions: Case Study of Signal Crayfish
in Sierra Nevada (CA) Streams
Theo S. Light ............................................ 168
The Role of Chemical Mimicry in the Ecology and Evolution of Symbioses Between Lycaenid
Butterfly Caterpillars (Lepidoptera: Lycaenidae) and Ants (Hymenoptera: Formicidae)
David J. Lohman .......................................... 169
Characterization of Sources of Indoor Particles Using Continuous Mass and Size Monitors
Christopher M. Long ........................................ 171
Dust Resuspension by Wind and the Implications for Contaminant Transport
Gwen A. Loosmore ......................................... 172
Photolytic Impact on Dissolved Organic Matter: Implications for Copper-Organic Binding
and Toxicity in Natural Waters
Marjorie B. Lovvorn ........................................ 173
Teosinte Branchedl and the Development of the Adult Form
Lewis N. Lukens .......................................... 174
Quantitative Measures of Change in Pleistocene Mammal Distributions
and Community Composition
Sara K. Lyons ............................................ 175
Negotiated Access: Emerging Institutional Formations in the Forestry Sector
of the Post-Soviet Russian Far East
Marian J. Mabel ................ ........................... 176
Population Dynamics of Methane-Oxidizing Bacteria in Flooded Soils: Environmental
Controls on Competition Between Physiological Groups
Jennifer L. Macalady ........................................ 177
Atmospheric Organic Nitrogen — Origin, Speciation, and Significance in Global Marine
Biogeochemistry
Kimberly A. Mace ......................................... 179
Population Genetics of a Vertebrate Community in a Patchy Environment
Mollie K. Manier .......................................... 180
Use of Stable Sulfur Isotopes in Ice Cores as Tracers of Paleoprecipitation Sources
Jacqueline L. Mann ......................................... 181
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STAR Graduate Fellowship Conference
Biological Denitrification of Nitrate Contaminated Groundwater in a Membrane Bioreactor
Bruce O. Mansell 183
Modeling Regional Scale Ozone Sensitivity to Precursor Emissions With a Fuel-Based
Motor Vehicle Emission Inventory
Linsey C. Marr 184
Theory and Practice of Public Meetings
Katherine A. McComas 185
Biotic and Abiotic Transformation of Carbon Tetrachloride During Microbial
Iron Reduction
Michael L. McCormick 186
Modeling Effective Land Use Decisions for Urban Areas
Althea L. McCoy 187
Controlling the Forest Understory: Wild Mushroom Politics in Central Oregon
Rebecca J. McLain 188
Large-Scale Movement Patterns and Genetic Structuring Among Puma Populations
in a Fragmented Landscape
BradH. McRae 189
Mormon and Catholic Perspectives on National Forest Management
Nancy L. Menning 190
The Influence of Surface Water Constituents on the Photochemical Transformation
of Non-Point Source Pollutants
Penney L. Miller 191
Molecular Monitoring of Microbial Populations During Bioremediation
of Contaminated Soils
DeEtta (Dee) K. Mills 193
Investigation of Waterborne Microsporidia
Jeffrey T. Mital 194
Forest Management and Fruit Harvest in Amazonian Forest
Susan M. Moegenburg 195
Surfaced Enhanced Raman Scattering From Silver Fractal and Biological Specimen
Joseph R. Montoya 197
Redox Changes in the Groundwater Environment: Implications for Natural Attenuation
of Chlorinated Ethenes
Angela M. Moore 198
Adaptive Optimal Control and the Reduction of Uncertainty in Managing a Georgia
Piedmont Forest for Multiple Wildlife Objectives
Clinton T. Moore 199
XI
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STAR Graduate Fellowship Conference
Variations in Fog and Cloud Composition With Droplet Size and Their Influence on
Aerosol Processing
Katharine F. Moore 200
A Remote Sensing Assessment of Land Use and Land Cover Changes Within the Headwaters
Region of the Rio Conchos Watershed, Chihuahua, Mexico
Pedro Muela 202
Temporal Links Between Climate and Hydrology: Insights From Central Texas Cave
Deposits and Groundwater
MaryLynn Musgrove 203
Receptor-Based Modeling of Groundwater Contamination
Roseanna M. Neupauer 205
Environment as Social Context: A Study of Persistent Places in the Archaeology
of the Flagstaff Region, Arizona
Joanne M. Newcomb 207
Nesting Success of a Hawaiian Honeycreeper Along an Altitudinal Gradient
of Culicine Mosquitoes
Bonnie M. Nielsen 208
Torres Strait Marine Foraging and Marine Resource Utilization
Karma C. Norman 209
Transport and Retention of Bay Anchovy and White Perch in Chesapeake Bay
Elizabeth W. North 210
Escaping the Growth Management Conundrum: Local Commitment to Land Use Plan
Implementation in Coastal North Carolina
Richard K. Norton 212
Sahelian Elephant Research and Conservation Project
Anne M. Orlando 213
Analysis of Fluorescence Responses of PAH Mixtures
Todd E. Pagano 215
Characterization and Utilization of Instruments for Real Time Single Particle
Analysis in Laboratory and Field Measurements
Syliva H. Pastor 216
An Enhanced Aerosol Size Distribution Methodology
Roderick R. Pearson 217
Metal Speciation and Sequestration in Wetland Systems
Edward Peltier 218
Colloidal Stability in Aquatic Systems: The Roles of Calcium and Natural Organic Matter
Adrian C. Penisson 219
XII
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STAR Graduate Fellowship Conference
The Long-Term Evolution of Community Structure Among Benthic Marine Invertebrates
Shanan E. Peters 221
Environmental Salinity and Stingray Gills: From Biochemistry to Conservation Biology
Peter M. Piermarini 223
Risk-Tradeoffs in Decision-Making: The Malaria/DDT Dilemma
MontiraJ. Pongsiri 224
Transition Metal Homeostasis in Saccharyomyces Cerevisiae
Matthew E. Portnoy 226
Species Life History Traits, Spatial Patterning and Density in Tropical Forests: Patterns
and Processes
Matthew D. Potts 227
Heterogeneous Nucleation of Ice on Soot Aerosol
Anthony J. Prenni 228
Development and Demonstration of a Hollow Fiber Membrane Bioreactor for Cometabolic
Degradation of Chlorinated Solvents
Jonathan G. Pressman 229
Physiological Effects of Ciliate Epibionts on a Harpacticoid Copepod
Gwyn L. Puckett 231
Multiple Pesticide Exposure: Immunotoxicty and Oxidative Stress
Christine L. Rabideau 232
Role of the Tumor Suppressor Gene, P53, in PAH-Mediated Carcinogenesis
in Two Species of Ictalurid Catfish
Michelle A. Rau 233
Private Rights in Public Resources: The Role of Equity in Market-Based
Environmental Policies
Leigh S. Raymond 234
Long-Term Changes in the Species Composition of Calanoid Copepods Off
Southern California
Ginger A. Rebstock 236
Cost Effective Long-Term Groundwater Monitoring Design
Patrick M. Reed 237
Trade and Environmental Policy: An Analysis of the Technology Effect
Valerie Reppelin 238
Physical Circulation of the Neuse River Estuary (NRE) and Its Contribution
to the Occurrence of Fish Kills
Janelle V. Reynolds-Fleming 239
Characterization of Reductive-Dechlorinating Microbial Communities Using a Combination
of Fluorescent In Situ Hybridization and PCR-Based Molecular Tools
Ruth E. Richardson 240
xiii
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STAR Graduate Fellowship Conference
Carbon Storage and the Timing of Leaf Flush
Renee A. Richer 242
Sequential Anaerobic/Aerobic Treatment of Polychlorinated Biphenyls in Soil
Julia D. Rogers 243
Individual Growth Rates and Population Demography of White-Flowered Trillium (Trillium
Grandiflorum) Across Gradients of Light, Fertility, and Deer Browsing Pressure
Thomas P. Rooney 245
Mechanisms Driving the Extirpation of a Desert Fish Species
Jonathan A. Rosenfield 246
Methods for Optimizing Municipal Environmental Ordinances Within Westchester
County's Croton Watershed Plan
Joyce E. Rosenthal 247
Genetic Engineering of a Radiation Resistant Bacterium for Biodegradation of Mixed Wastes
Heather M. Rothfuss 248
Do Enemies of Herbivores Shape the Evolution of Plant Traits? Wild Cotton
and Extrafloral Nectaries
Jennifer A. Rudgers 249
Simulated Effects of Elevated Nitrogen Deposition on Colorado Englemann Spruce Forests
Heather M. Rueth 250
The Effect of Windthrow Disturbance and Salvage Logging on Nutrient Cycling
in a Coniferous Forest Ecosystem
CristinaM. Rumbaitis-del Rio 251
Shallow Intermittent Sand Filtration: Design Optimization and Effluent
Characterization for Reuse
Loret M. Ruppe 252
Environmental Benefits and Impacts of Japanese International Environmental Aid
Daniel J. Rutherford 253
Genetic Variation in Phragmites Australis
Kristin Saltonstall 254
Effect of Bioavailable Metal Concentration on Mechanisms of Metal Resistance
Todd R. Sandrin 256
Physiological Stress Responses, Aggression and Social Dominance in Wild Wolves
Jennifer L. Sands 257
Environmental Geochemistry of Arsenic, Southern Mother Lode Gold District, California
Kaye S. Savage 259
Native Hawaiian Claims and Claims About Native Hawaiians
Jonathan L. Scheuer 261
xiv
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STAR Graduate Fellowship Conference
Patterns of Tail Autotomy in Three Different Populations of a Neotropical Lizard,
Norops Polylepis
Martin A. Schlaepfer 262
A Comparison of Decomposition in Restored and Natural Non-Tidal Forested Wetlands
in Eastern Virginia
J. Michael Schmidt 263
Floodplain Management and Ecosystem Function on the Stanislaus River: An Evaluation
of Hydrologic and Fluvial Geomorphologic Alteration
Katrina S. Schneider 265
Water and Nutrient Fluxes From Submarine Groundwater Discharge in the Delaware Estuary
Matthew C. Schwartz 267
Cnidarian-Algal Symbiosis: Expression and Synthesis of a Symbiosis Protein, Sym32,
in Two Cnidarians
Jodi A. Schwarz 268
Predictive Soil Modeling in Soil Survey
Peter R. Scull 270
An Assessment of Families' Exposures To, and the Relationships Between, Personal, Indoor,
and Outdoor Air Concentrations of Fine Particles and Air Toxics: Riopa, Los Angeles
County, CA Site
Derek G. Shendell 271
Mechanistic Studies of Vitamin B12 Mediated Dechlorination
Justin Shey 273
Development of a Sustainable Management Framework for the University of Michigan
Housing Division
Michael P. Shriberg 274
Source Characterization and Apportionment of Airborne Particles Using Mass Spectrometry
Philip J. Silva 275
Water Use and Root Function of Tree Species in Semi-Arid Riparian Ecosystems
Keirith A. Snyder 276
Effects of Soil/Sediment Organic Matter on the Desorption, Bioavailability, Sequestration,
and Transformation of Phenanthrene
Sara B. Soderstrom 277
Sources of Nutrient Input in an Urbanizing Oregon Watershed
Kazuhiro Sonoda 279
Accumulation of Atmospheric and Sedimentary PCBs in a Lake Michigan Food Web
Heather M. Stapleton 280
The Effect of Elevated CO2 Concentrations and Vegetation Mortality on Mineral
Weathering in Soils
Jennie C. Stephens 282
xv
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STAR Graduate Fellowship Conference
Highland Maya Medical Ethnobotany in Ecological Perspective
John R. Stepp 283
Randomly Amplified Polymorphic DNA Profile-Based Measures of Genetic Diversity
as a Bioindicator of Environmental Stress
David C. Steinberg 284
Characterization of Non-Point Source Vadose Zone Pesticide Leaching at the Regional Scale
Using a Type Transfer Function Approach
Iris T. Stewart 286
From Motor City to Garden City: Sustainability and Urban Agriculture in Detroit
Karl M. Steyaert 287
Urban Form and Thermal Efficiency: How the Design of Cities Can Influence the Urban
Heat Island Effect
Brian Stone 288
Reductive Transformation of Agrochemicals in Model Aqueous Systems: Role of Ferrous
Iron Speciation
Timothy J. Strathmann 289
The Return of the Forest: Urbanization and Reforestation in the Northeastern United States
Ellen Stroud 290
A Modeling Investigation of the Effects of Solid-Phase Cloud Hydrometeors in Convective
Clouds on Chemical Distributions and Deposition
Amy L. Stuart 291
Forest Interior Songbird Diversity and Breeding Success as a Function of Topography
and Climate in the Mid-Atlantic Highlands
Brian R. Sturtevant 292
Science to Achieve Results Fellowship
Tim Sulser 294
The Mechanism of Cadmium Nephrotoxicity
WeifengTang 295
Impact of Cattle Grazing and Summer and Winter Drought on Soil Mite Populations
in the Northern Chihuahuan Desert
Hilda S. Taylor 296
The Political Ecology of Sustainable Agriculture in China: National Goals and Farmer Realities
Brian J. Thomas 298
Chemical and Biological Assessment of the Aquatic Ecosystem of the Houston Ship Channel
Renard Thomas 299
Rethinking Decision-Making in the Face of Scientific Uncertainty: Instituting Precaution
in Environmental Health Policy
Joel A. Tickner 300
XVI
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STAR Graduate Fellowship Conference
Understanding Covariance Function Dynamics for Improving Insect Spatial
and Temporal Management
Patrick C. Tobin 301
Adolescence as a Critical Period for Nicotine-Induced Neurotoxicity in the Developing Brain
Jennifer A. Trauth 302
Macroalgal Mediation of Dissolved Organic Nitrogen Dynamics in a Temperate
Coastal Lagoon
Anna C. Tyler 304
Airborne Measurements of Cloud Condensation Nuclei
Timothy M. VanReken 305
Characterization of Beggiatoa in Black Band Disease of Scleractinian Corals
T. Shay Viehman 306
(Re)claiming the Watershed: Property Lines, Treaty Rights, and Collaborative
Natural Resource Management Planning in Rural Oregon
Sissel A. Waage 308
Passive Aerosol Sampler to Estimate Long-Term Average Concentrations
and Size Distributions
JeffWagner 309
Ecosystem Consequences of Eurasian Watermilfoil (Myriophyllum Spicatum) Invasion
in Lake Tahoe, California-Nevada
Katey M. Walter 310
Development of a Quantitative Structure-Activity Relationship (QSAR) for Prediction
of Biodegradation Kinetics of Polycyclic Aromatic Hydrocarbons
Kristine H. Wammer 311
Environmental Estrogens and Breast Cancer Therapeutics: Characterization of the Diverse
Ligand Binding Properties of the Estrogen Receptor
Dana E. Warn 312
Effects of Enhanced UV-B Radiation on Poplar Phytochemistry and Herbivory
Jeffrey M. Warren 314
The Effects of the Cotreatments of Benzo(a)pyrene and Fluoranthene on the Expression
and Activity of Cytochrome P450 1A and on the Formation of DNA Adducts
in the Killifish, Fundulus Heteroclitus
DeenaM. Wassenberg 316
Dine Bikeyah: Environment, Cultural Identity, and Gender in Navajo Country
Marsha L. Weisiger 317
Smog Check: A Case Study in Environmental Decision Making
Louise L. Wells 318
Urban Redevelopment: Assessing Legal Rights and Responsibilities
Hope S. Whitney 319
XVII
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STAR Graduate Fellowship Conference
Seed Dispersal and Seed Predation in Acacia Ligulata: The Role of Plant-Animal
Interactions in Maintaining Within-Population Genetic Diversity
Kenneth D. Whitney 320
A Study of the Environmental Justice Issues Associated With the Growing Swine
Industry in Mississippi
Sacoby M. Wilson 321
Ecological and Evolutionary Constraints to Herbivore Resistance in a Native Plant - Multiple
Herbivore Community
Michael J. Wise 322
Catastrophe, Uncertainty, and the Costs of Climate Change Damage
Evelyn L. Wright 324
Protocol for Cryptosporidium Risk Communication for Drinking Water Utilities
Felicia Wu 325
Water Quality Impacts of Riparian Buffers
Theresa M. Wynn 326
Site Specific Oxidations of Organic Compounds in Water
Jerry C.Yang 327
Tibet's Economic Reform: Greenhouse Agriculture and a Hegemony of Tibetan Indolence
Emily T. Yeh 329
Liquid Phase Mass Transfer in Spray Contractors
Norman K. Yeh 330
Understanding Community and Ecosystem Responses to Interacting Global Changes
Erika S. Zavaleta 331
Environmental Democracy: An Analysis of Brownfields Policy Making
AmyA.Zeitler 333
Operational Induced Changes in Geomembrane Surface Topography
Tamara E. Zettler 334
SUBJECT INDEX
Chemistry and Materials Science
Cardille, Jeffrey A. 38
Conell, Matthew A. 58
Dokken, Kenneth M. 75
Gaizick, Lia M. 104
Garland, Eva R. 105
Hauser, Cindy D. 121
Hobbs, Terry R. 131
xviii
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STAR Graduate Fellowship Conference
Jameton, Rachel A. 139
Klupinski, Theodore P. 156
Miller, Penney L. 191
Mital, Jeffrey T. 194
Pagano, Todd E. 215
Pastor, Sylvia H. 216
Raymond, Leigh, S. 234
Shey, Justin 273
Silva, Philip J. 275
Stapleton, Heather M. 280
Yang, Jerry C. 327
Earth Sciences
Ambers, Rebecca 5
Bryner, Jeanna R. 33
Carlson, Charles T. 40
Churcher, Tegan P. 49
Crowe, Joanna C. 59
Day-Lewis, Frederick D. 67
Duckworth, Owen W. 81
Ede, Alissa M. 88
Funk, Chris C. 102
Harrington, Thomas B., Jr. 116
Hart, Robert 119
Henry, Mary C. 127
Johnson, Stephanie E. 142
Katz, Gabrielle L. 145
Kenworthy, Stephen T. 149
Keon, Nicole E. 150
Mann, Jacqueline L. 181
Moore, Katharine F. 200
Muela, Pedro 202
Musgrove, MaryLynn 203
Pearson, Roderick R. 217
Peters, Shanan E. 221
Prenni, Anthony J. 228
Savage, Kaye S. 259
Scull, Peter R. 270
Stephens, Jennie C. 282
Stewart, Iris T. 286
Stuart, Amy L. 291
Ecology and Ecosystems
Alexander, Janice M. 4
Ardia, Daniel R. 9
Baco-Taylor, Amy R. 10
Bakkcr, Victoria J. 14
Bartholomew, Aaron 15
Beauchamp, Vanessa B. 16
Benoit, Janina M. 20
xix
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STAR Graduate Fellowship Conference
Birchfield, Gayle L. 21
Bjork, Robin D. 22
Boyer, Katharyn E. 29
Brass!!, Chad E. 31
Buffam, Ishi D. 34
Capers, Robert S. 36
Cheeseman, Ted F. 43
Cheruvelil, Kendra S. 45
Clark, Connie J. 51
Cohen, Risa A. 53
Colin, Sean P. 55
Conway, Carole A. 57
DeJoode, Daniel R. 68
Dillon, Michael E. 72
Dixon, Mark D. 74
Feldpausch, Ted R. 94
Ferguson, Patrick L. 96
Fotheringham, C.J. 99
Funk, Jennifer L. 103
Gaskin, John F. 106
Gergel, Sarah E. 107
Goetze, Erica 109
Greenfield, Ben K. Ill
Harris, Wylie N. 117
Hauxwell, Jennifer A. 122
Hayes, Tom D. 123
Heaton, Andrew C. 125
Horton, Jonathan L. 134
Huff, Thomas B. 138
Katzner, Todd E. 146
Kerr, Alexander M. 152
Klug, Jennifer L. 154
Lach, Lori J. 160
Latta, Steven C. 163
Lewis, David B. 166
Licata, Amy Collins 167
Light, Theo S. 168
Lyons, Sara K. 175
Macalady, Jennifer L. 177
Mace, Kimberly A. 179
McRae, Brad H. 189
Moegenburg, Susan M. 195
Moore, Clinton T. 199
Nielsen, Bonnie M. 208
North, Elizabeth W. 210
Orlando, Anne M. 213
Potts, Matthew D. 227
Rebstock, Ginger A. 236
Reynolds-Fleming, Janelle V. 239
Richer, Renee A. 242
Rooney, Thomas P. 245
Rudgers, Jennifer A. 249
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STAR Graduate Fellowship Conference
Rueth, Heather M. 250
Rumbaitis-del Rio, Cristina M. 251
Schlaepfer, Martin A. 262
Schmidt, J. Michael 263
Schwartz, Matthew C. 267
Snyder, Keirith A. 276
Sonoda, Kazuhiro 279
Sturtevant, Brian R. 292
Taylor, Hilda S. 296
Tyler, Anna C. 304
Walter, Katey M. 310
Warren, Jeffrey M. 314
Whitney, Kenneth D. 320
Wilson, Sacoby M. 321
Wise, Michael J. 322
Zavaleta, Erika S. 331
Economics and Business
Baerenklau, Kenneth A. 11
Duke, Richard D. 82
Kotchen, Matthew J. 159
Reppelin, Valerie 238
Shriberg, Michael P. 274
Wright, Evelyn L. 324
Engineering
Bell, Michelle L. 17
Benaman, Jennifer 18
Bondehagen, Diane L. 24
Church, Clinton D. 46
Clayton, John M. 52
Dargan, Tarsha N. 63
Davis, Christina C. 66
Dunahee, Nathaniel K. 84
Escobar, Isabel C. 89
Fleming, Maia S. 98
Fox, Garey A. 101
Holman-Dodds, Jennifer K. 132
Hornbuckle, Brian K. 133
Johnson, Martin D. 141
Keinath, Michael 148
Loosmore, Gwen A. 172
Mansell, Bruce O. 183
Marr, Linsey C. 184
McCormick, Michael L. 186
Moore, Angela M. 198
Neupauer, Roseanna M. 205
Peltier, Edward 218
Penisson, Adrian C. 219
xxi
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STAR Graduate Fellowship Conference
Pressman, Jonathan G. 229
Reed, Patrick M. 237
Richardson, Ruth E. 240
Rogers, Julia D. 243
Rothfuss, Heather M. 248
Ruppe, Loret M. 252
Rutherford, Daniel J. 253
Soderstrom, Sara B. 277
Strathmann, Timothy J. 289
VanReken, Timothy M. 305
Wagner, Jeff 309
Wammer, Kristine H. 311
Wells, Louise L. 318
Wynn, Theresa M. 326
Yen, Norman K. 330
Zettler, Tamara E. 334
Life Sciences
Adams, Nikki L. 1
Amweg, Erin L. 6
Bakermans, Corien 12
Bowman, Christopher J. 27
Cerchio, Salvatore 41
Colby, Deanna M. 54
Conder, Jason M. 56
Dam, Kristina 61
Dethlefsen, Les 70
DiFazio, Stephen P. 71
Doukakis, Phaedra 77
Dowd, Scot E. 78
Dunn, Anne K. 85
Durham, Debra L. 86
Etinier, Michael 90
Evans, Timothy J. 92
Fecker, Jesse A. 93
Griffin, Benjamin M. 112
Gustavson, Karl E. 113
Harmon, Jason P. 115
Hatch, Audrey C. 120
Heasley, Lynne 124
Hecht, Scott A. 126
Houghton, David C. 136
Hsu, Cynthia L. 137
Johnson, David S. 140
Karpanty, Sarah M. 143
Kern, Eric A. 151
Kockelman, Paul D. 157
Lohman, David J. 169
Loworn, M arjorie B. 173
Lukens, Lewis N. 174
Manier, Mollie K. 180
xxii
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STAR Graduate Fellowship Conference
McLain, Rebecca J. 188
Menning, Nancy L. 190
Mills, DeEtta (Dee) K. 193
Newcomb, Joanne M. 207
Norman, Karma C. 209
Piermarini, Peter M. 223
Portnoy, Matthew E. 226
Puckett, Gwyn L. 231
Rabideau, Christine L. 232
Rau, Michelle A. 233
Rosenfield, Jonathan A. 246
Saltonstall, Kristin 254
Sandrin,ToddR. 256
Sands, Jennifer L. 257
Schwarz, Jodi A. 268
Steyaert, Karl M. 287
Tang, Weifeng 295
Thomas, Renard 299
Tobin, Patrick C. 301
Trauth, Jennifer A. 302
Viehman, T. Shay 306
Warn, Dana E. 312
Wassenberg, Deena M. 316
Mathematical Sciences/Physics
Hiebler, David E. 129
Montoya, Joseph R. 197
Risk Assessment/Risk Communication
Chapa, Guadalupe 42
Clark, Catherine M. 50
Doran, Ed M. 76
Easton, John H. 87
Hansen, Laura C. 114
Long, Christopher M. 171
McComas, Katherine A. 185
Shendell, Derek G. 271
Stern berg, David C. 284
Social Sciences
Albert, Jeff 3
Anchukaitis, Kevin J. 7
Andrews, Thomas G. 8
Benjamin, Charles E. 19
Borsuk, Mark E. 25
Brody, Samuel D. 32
Calamia, Mark A. 35
Caplan, Christina C. 37
xxni
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STAR Graduate Fellowship Conference
Chen, Linus Y. 44
Daley, Dorothy M. 60
Daro, Vinci E. 64
Derr, Victoria L. 69
Driscoll, Lori L. 79
Firestone, Jeremy M. 97
Greacen, Christopher E. 110
Herrold, Melinda K. 128
Higgins, Lorie L. 130
Klingle, Matthew W. 153
Kosek, Jon 158
Larson, Anne M. 161
Levesque, Suzanne M. 165
Mabel, Marian J. 176
McCoy, Althea L. 187
Norton, Richard K. 212
Pongsiri, Montira J. 224
Rosenthal, Joyce E. 247
Scheuer, Jonathan L. 261
Schneider, Katrina S. 265
Stepp,John R. 283
Stone, Brian 288
Stroud, Ellen 290
Sulser, Tim 294
Thomas, Brian J. 298
Tickner, Joel A. 300
Waage, Sissel A. 308
Weisiger, Marsha L. 317
Whitney, Hope S. 319
Wu, Felicia 325
Yeh, Emily T. 329
Zeitler, Amy A. 333
XXIV
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Science To Achieve Results (STAR)
Graduate Fellowship Conference 200O
ABSTRACTS
July 9-12, 2000
Washington, DC
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STAR Graduate Fellowship Conference
U915222
BEHAVIORAL DEFENSES AGAINST ULTRAVIOLET RADIATION BY THE GREEN SEA
URCHIN STRONGYLOCENTROTUS DROEBACHEENSIS
Nikki L. Adams
University of Maine, Orono
Objectives/Hypotheses: To understand how marine invertebrates are affected by and protect themselves
against ultraviolet radiation (UVR).
Rationale: Marine invertebrates are exposed to potentially damaging levels of UVR. UVR may alter
behavioral patterns and affects the physiology and development of marine invertebrates. Decreases in our
stratospheric ozone layer, and concomitant increases in transmission of UVB wavelengths between 295-320
nm, have intensified the need to understand effects of UVB on aquatic organisms. Organisms may receive
protection by avoiding exposure during hours of peak irradiation or they may use other modes of protection
if they are sessile or they cannot avoid exposure to UVR. Adult green sea urchins, Strongylocentrotus
droebachiensis, and many other species of sea urchins hide among rocks or cover themselves with debris,
including macroalgae, shells, and pebbles, typically in response to bright sunlight. This behavior has been
hypothesized to be a reaction to UVR, but this supposition had not been demonstrated conclusively, A
controlled study was important to determine whether UVR specifically affects the behavior (and ultimately
the distribution) of sea urchins.
Approach; This study examined the response of green sea urchins specifically to environmentally relevant
ultraviolet radiation (UVR, 295-400 nm). In laboratory studies using artificial irradiance to test phototaxis
and the covering response, green sea urchins sought shade and covered themselves more frequently when
exposed to photosynthetically active radiation (PAR, 400-700 nm) and UVR than urchins exposed only to
PAR (P<0.05). In outdoor aquaria, sea urchins were exposed to solar radiation that was filtered to create four
treatments (dark, PAR, PAR+UVA (320-400 nm), or PAR+UVA+UVB) and observed for 6 hours as total
solar irradiance changed with time of day. Sea urchins covered themselves with more material when ex-
posed to PAR + UVA + UVB than in all other treatments (P<0.05), and in response to total irradiance
(PO.05). The amount of covering by sea urchins exposed to PAR + UVA varied over the course of the day,
but less than urchins exposed to UVB. These urchins covered themselves more than urchins exposed to PAR
alone and than urchins held in the dark (P<0.05), which did not differ from one another in amount of
covering, regardless of time of day (P>0.05). The amount of covering correlated significantly with UVB and
UVA irradiance independently (P<0.001), but not with PAR irradiance (P>0.05). These results demonstrate
for the first time that green sea urchins are negatively phototactic and cover themselves in response to UVR,
primarily to UVB wavelengths or a combination of UVA and UVB, presumably to avoid UV-induced
damage.
Status; These results have been submitted for publication (see below). Further experiments should address
how avoidance and covering behavior varies among species of sea urchins and whether increased levels of
UVB affects their population dynamics, This study is part of a larger investigation examining photo-
oxidative stress in marine invertebrates and the role of biochemical defenses against UVR. Two additional
papers have been submitted as a result of this project.
Papers & Publications: Adams, N.L. UV radiation evokes negative phototaxis and covering behavior in
the green sea urchin Strongylocentrotus droebachiensis. (submitted to Mar Ecol Prog Ser)
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STAR Graduate Fellowship Conference
Adams, N.L. and Shick, J.M. 1996. Mycosporine-like amino acids provide protection against ultraviolet
radiation in eggs of the green sea urchin, Strongylocentrotus droebachiensis. Photochem Photobiol 64,149-
158.
Adams, N.L. and Shick, J.M. Mycosporine-like amino acids prevent UVB-induced abnormalities during
development of the green sea urchin Strongylocentrotus droebachiensis. (submitted to Mar Biol)
Adams, N.L., Shick, J.M., and Dunlap, W.C. Selective accumulation of mycosporine-like amino acids in
ovaries of the green sea urchins, Strongylocentrotus droebachiensis, is not affected by ultraviolet radiation.
(submitted to Mar Biol)
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STAR Graduate Fellowship Conference
U915662
WASTEWATER IRRIGATION AND ELEVATED GROUND WATER CHLORIDE
CONCENTRATIONS IN ISRAEL AND PALESTINE
Jeff Albert
Yale University
Objectives/Hypotheses; To evaluate the claim that agricultural irrigation using treated wastewater is
increasing the salinity of aquifers in Israel and Palestine.
Rationale: Increasing population pressures and prevailing climatic conditions have caused Israeli agri-
culture to become dependent on treated wastewater for its irrigation needs. Palestinian agriculture is likely
to follow suit in the coming years. The EPA and USAID have jointly issued guidance promoting the benefits
of wastewater irrigation as a means of both water supply augmentation and pollution abatement, particularly
in arid and semi-arid areas (EPA/USAID, 1992). At the same time, growing concerns are being voiced in
the region about the elevation of groundwater and soil salinity as an alleged result of wastewater irrigation
(Zaslavsky, 1999). These concerns stem from the fact that the wastewater treatment technologies in
widespread use in the region (activated sludge, trickling filter, and pond/reservoir systems), while efficient
at removing suspended solids and oxygen demand, tend not to decrease (and in many instances actually
increase) total dissolved solid (TDS) concentrations. It has been argued that irrigation using treated
wastewaters high in TDS has already substantially elevated the salinity of underlying groundwaters, but
evidence for the relationship between wastewater irrigation and groundwater salinity increases is based on
bench-scale and small field-scale findings rather than full landscape-scale empirical surveys.
Approach; The Israeli government maintains a groundwater chemistry monitoring network of some 2,500
wells whose spatial density surpasses 3 wells/km2 in portions of the Israeli coastal region, with several
measurements per year going back three decades. It also maintains fairly detailed agricultural records as
well as data on freshwater and reclaimed wastewater irrigation outlays. In the first component of my
research, data on groundwater chemistry and irrigation, together with an extensive collection of digital land
cover and aquifer media information, will be combined to produce a geostatistical model using a raster GIS
with change in groundwater Cl' concentration, D[Cl-]gw, as the dependent variable. CP is an appropriate
measure of salinity in this case because it is an inert conservative chemical species whose sources are nearly
entirely anthropogenic. In the second component, geographic areas in which there is a high correlation
between wastewater irrigation and D[Cl']gw will be compared with several control sites in which irrigation
without wastewater has been practiced for a period of >10 yr.
Status; Chloride datasets as well as ancillary digital map data have been obtained and are presently being
harmonized and QA/QC inspected. Preliminary data coverages on wastewater irrigation have been gen-
erated, but need to be linked with an agricultural GIS for a more precise estimate of wastewater irrigation
volumes. Completion of the first component of the proposed research is envisioned to occur by September
2000.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915607
SEED BANKS AND PRESCRIBED BURNS: FACTORS AFFECTING SUCCESSFUL
CONTROL OF FRENCH BROOM AND RESTORATION OF NATIVE COMMUNITIES
IN COASTAL CALIFORNIA GRASSLANDS
Janice M. Alexander
University of California, Berkeley
Objectives/Hvpotheses: French broom (Genista monspessulana) is an invasive shrub from Europe now
abundant in California. Once established, broom plants form dense, practically monotypic stands that
displace grassland species. In an effort to restore native plant communities and reduce fuel loads, land
managers in Marin Co, CA, remove French broom through cutting, pulling, and prescribed burning. To
completely control broom, however, it is necessary to remove both living biomass and the seed bank. My
research assesses management efforts with reference to the broom seed bank, the native seed bank, and the
success of revegetation of native plants. I am building a simple model demonstrating the dynamics of native
and broom seed banks under different aged broom stands. I am also investigating how prescribed fires
influence emergence and persistence of the seed banks, and the revegetation potential of post-broom
communities.
Rationale; This information will aid managers in restoring native plant communities after the removal of
French broom. This study will be especially useful to the managers currently combating broom on their
lands, but may also be important in aiding our general understanding of the seed banks of invasive,
non-native plants and their dynamic relationship with control efforts and habitat restoration. As unaltered
landscapes become scarcer, this type of research becomes more relevant to and valuable for our efforts to
preserve native species and habitats.
Approach; I surveyed the community composition of areas that had received different types of management
treatments to assess which environmental factors are importantin effectively controlling broom and restoring
native plants. The seed bank was sampled within discrete, established French broom stands in oak woodland
understory and coastal grassland habitats in Marin Co. The broom stands were of differing ages and had
been burned one, two, three or four times, or not at all. Within a broom patch, I took soil samples along a
transect and recorded the density of broom plants. Soil cores were spread out to germinate in a latthouse.
The number of germinating seeds of all species were counted, as well as the number of dormant and dead
broom seeds. The age of the stands was estimated by counting growth rings of the largest broom individuals.
Status; I have finished data collection and am working on data entry and analysis. I will begin writing this
fall and will finish with my thesis in spring 2001.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915362
SEDIMENTATION, MERCURY CONTAMINATION, AND CLAY MINERALOGY
OF THE DORENA LAKE WATERSHED, WESTERN OREGON
Rebecca Ambers
University of Oregon
Objectives/Hypotheses; I examined reservoir and stream sediments from a large (686 sq. km) watershed
to determine: 1) the extent to which storm events and logging influence the sediment yield of a large
watershed; 2) the history of mercury contamination in the lake resulting from the use of mercury in gold
mining in the watershed; and 3) the relationship between the clay mineralogy of soil and bedrock, mass
movement processes, and topography of the watershed.
Rationale; In recent years, the Pacific Northwest has been the focus of intensive research and controversy
over the effects of land use on hillslope erosion, water quality, and fish habitat. Most sediment-monitoring
studies have been performed on small, experimental watersheds, but these results cannot be directly
extrapolated to larger basins. Instead, I used reservoir sediment collected over 50 years in Dorena Lake to
address certain environmental questions in a large watershed near the town of Cottage Grove, Oregon, in the
western Cascade Mountains.
Approach; I performed a sedimentation survey to measure the amount of sediment deposited in the
reservoir since the dam was completed in 1949. I also characterized lake-bottom sediment cores in terms
of sedimentology, stratigraphy, organic content, and metal content. Cs-137 dating was used to verify the
stratigraphic correlations. The clay mineralogy of suspended sediments from streams throughout the area
was used to characterize the bedrock and soil of the watershed, and I compared these data to topography and
landslide maps.
Status; This project is complete.
Papers & Publications; Ambers, R. Using the sediment record in a western Oregon flood-control reservoir
to assess the influence of storm history and logging on sediment yield. J Hydrol (in review)
Ambers, R. Relationships between clay mineralogy, hydrothermal metamorphism, and topography in a
Western Cascades watershed, Oregon, USA. Geomorphol (in review)
Ambers, R. and Hygelund, N. Contamination of two Oregon reservoirs by cinnabar mining and mercury
amalgamation. Environ Geol (in press)
Ambers, R. 1999. Reservoirs on the Willamette River system: An underutilized information resource?
Geol Soc America, Abstr Prog 31:223.
Ambers, R. and Dorsey, R. 1998. Effects of geology and land use on the concentration and clay mineralogy
of suspended sediments in streams of the Dorena Lake watershed, western Oregon: Eos, Trans. Am Geo-
phys Union 79:303-304.
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STAR Graduate Fellowship Conference
U915656
DEVELOPMENTAL EFFECTS OF COMPLEX POLLUTANT MIXTURES:
ORGANOPHOSPHATES, ALKYLPHENOLS,
AND LARVAL SALMONID OSSIFICATION
Erin L. Amweg
University of California, Berkeley
Objectives/Hypotheses: To determine if estrogenic pollutants alleviate adverse effects of organophosphate
pesticides by altering pesticide metabolism. This study will explore the resultant outcome of combined
contaminant mixtures on biochemical endpoints and on an ecologically significant endpoint, larval bone
development.
Rationale; The world's bay and estuaries accumulate man-made compounds from industrial and municipal
effluents discharged directly into the water supply, from atmospheric deposition, and from land-based runoff
containing agricultural chemicals. In order to maintain ecosystem function while sustaining ecosystem
services, regulators must understand the cumulative effect of various pollutants in estuaries. Therefore,
understanding the integrated biological effects of pollutant mixtures is necessary for future management
success. In this study, I will explore a possible antagonistic relationship between two classes of environ-
mental toxicants, environmental estrogens and organophosphate pesticides. Organophospate pesticides are
widely used in the United States. They induce p450 enzymes that biotransform the pesticides into their
active oxon form, which is both carcinogenic and neurotoxic, inhibiting acetylcholinesterase. Externally
induced enzymatic activity can subsequently alter numerous hormone dependant biological processes such
as bone development. There is evidence that estrogen acts to decrease p450 activity; thus, environmental
estrogens may partially protect organisms from damage due to p450-activated compounds, such as
organophosphates, when found simultaneously with these pesticides.
Approach: This research will be conducted in three stages: 1) pollutant exposures; 2) in vitro mechanistic
experiments; and 3) field measurements of actual contaminant loads in the Sacramento-San Joaquin drain-
age basin, California. 1) Exposures will be conducted using various combinations and dosing regimes of
malathion and nonylphenol. Larval fishes will be raised from hatch and exposed through either water or diet
for 7-30 days post-hatch or once via injection into the yolk sac of the developing fry. Carboxylesterase,
acetylcholinesterase, and p450 activity will be assessed in liver tissue. Bone precursor cells will be localized
during migration and differention by in situ immunostaining techniques. Bone density will be measured and
structural skeletal endpoints will be assessed after clearing and staining the fish. 2) The mechanism through
which these two chemicals mediate their effects on the organism will be explored by estrogen receptor and
aryl-hydrocarbonreceptorbindingassays, p450 transactivation assays, and enzymatic analysis (EROD) using
nonylphenol and malathion as competitive substrates. 3) Finally, chemical analysis of water and sediment
samples, prey items, and fish tissue will be conducted along the Sacramento and San Joaquin Rivers and their
Delta to quantify levels of several organophosphate pesticides and known environmental estrogens in the
aquatic habitat around San Francisco Bay. Collections of juvenile fall-run chinook and rainbow trout along
the estuary and comparison of skeletal defects to those induced in the laboratory will allow crude estimates
of the current potential impact of pollutants on wild fish populations.
Status; Preliminary laboratory exposures will begin in April 2000 following construction of a water
purification system. Exposure studies are expected to be complete by fall 2001. Mechanistic studies and
field verification will begin in fall 2001 and the expected completion date is fall 2002.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915633
LATE HOLOCENE FOREST HISTORY
IN THE GOTO BRUS REGION OF COSTA RICA
Kevin J. Anchukaitis
University of Tennessee, Knoxville
Objectives/Hypotheses; This research reconstructs forest composition and vegetation patterns for the late
Holocene in the Goto Brus region of southwestern Costa Rica, identifying periods of both change and
stability influenced by environmental and anthropogenic factors.
Rationale; The traditional view of Central American forests is one of "virgin" vegetation only recently
disturbed in historic times by European settlers and modern commercial and industrial activity. In fact,
mounting evidence supports the assertion that pre-historic human agriculturalists throughout Central
America altered the patterning and composition of forest vegetation. Forests were also affected by changes
in climate and other physical environmental factors. The numerous pre-Columbian sites discovered by
archaeologists in the Goto Brus region of southwestern Costa Rica indicates that human modification of the
landscape probably began well in advance of European arrival. A complete understanding of both the
environmental and human influences on forest structure and composition is a critical prerequisite for both
modern ecological studies and the development of policies for managing lowland tropical forests in
developing countries. This research contributes to a body of knowledge currently being developed on the
paleoecology of the Neotropics.
Approach; Paleoecological methods are used to reconstruct past landscapes. Specifically, identification
and tabulation of pollen assemblages preserved in lake sediments allows the creation of a chronological
sequence of changing forest composition. Pollen assemblages are interpreted based on known relationships
between modern vegetation, pollen distributions and environmental factors. The object is to reconstruct past
vegetation patterns and correlate them with specific environmental and/or human factors. Frequency and
distribution of charcoal in the sediment record is analyzed to understand fire history and changes in fire
regimes. Chemical composition and deposition rates of lake sediments are determined in order to examine
watershed erosion potentially tied to human land use practices.
Status; Sediment cores were recovered from two lakes in the Goto Brus region in January 2000. Processing
of samples, including radiocarbon dating, is ongoing.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915609
THE ROAD TO LUDLOW: WORK, ENVIRONMENT, AND INDUSTRIALIZATION
IN SOUTHERN COLORADO, 1870-1915
Thomas G. Andrews
University of Wisconsin, Madison
Objectives/Hypotheses: "Labor versus the environment"—since a trade-off between environmental
protection and blue-collar jobs was first posited, policy makers, environmentalists, economists, sociologists,
and others have debated this perceived conflict in a number of ways. But, with few exceptions, they have
done little to incorporate historical perspectives into these analyses. This is regrettable, for the past promises
to provide important insights into current and future debates on labor and the environment.
Rationale; As the United States economy grew ever more industrialized, were the exploitation of labor and
the exploitation of labor connected? At home and at work, did working-class Americans suffer
disproportionately from environmental hazards? If so, did they organize to cope with these problems?
Finally, what role did concerns over the workplace and/or community environments play in disputes between
workers and management? These are important questions, for they prompt us to reconsider the "labor versus
the environment" trade-off. By perceiving this trade-off as intractable and inevitable, we risk losing sight
of the common ground that has long connected the travails of working-class Americans with the struggle for
environmental protection.
Approach: My dissertation uses the coal- and steel-producing area of southern Colorado in the late-
nineteenth and early-twentieth centuries as a case study to examine the interrelationships between workers,
the environment, and industrialization in the United States. It seeks both to explore the ways in which
environmental concerns provoked coal miners to strike in the 'coal war' of 1913-14 that resulted in the
infamous Ludlow Massacre, and to uncover the broader historical processes of environmental, social, and
technological change that led to the emergence of heavy industry in southern Colorado in the first place.
Status; I have completed about half of the necessary archival research, and expect to complete most of the
remainder by the end of 2000. From that point on, I will combine writing with research in newspapers and
published sources.
Papers & Publications; Andrews, T.G. The road to Ludlow: the work of nature and the nature of work
in the southern Colorado coal fields, 1870s to 1914. Presented at the annual meeting of the American
Society for Environmental History, Tacoma, WA, March 2000.
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STAR Graduate Fellowship Conference
U915336
CAUSES AND CONSEQUENCES OF INDIVIDUAL AND GEOGRAPHICAL
VARIATION IN BODY CONDITION AND REPRODUCTIVE SUCCESS
Daniel R. Ardia
Cornell University
Objectives/Hypotheses; To determine what role variation among individuals in their quality (genotype and
phenotype) plays in determining geographic variation in abundance and life history tradeoffs. My results
can help determine whether management must consider not only habitat quality but also the subset of
individuals found at a site.
Rationale; Different rates of survival and reproduction among individuals within a species underlie patterns
of distribution and abundance. Such differences can arise due to differences among sites in the quality of
habitat or in the quality of individuals or both. Individuals vary greatly (e.g., sex, age, size, condition, prior
experience, genotype). Interindividual differences lead to differences in quality that affect resource use and
demands, habitat selection, survival, and ultimately fitness. Describing and explaining underlying
mechanisms causing spatial variation in populations can help in predicting population persistence overtime.
The objective of my work is to investigate interactions between variation in individual quality and habitat
quality on both a local and geographic scale. My main research questions are: 1) how variable are
individuals within and among habitats along a geographic gradient; 2) why do individuals vary in quality
and what are the fitness consequences of intra- and interindividual variation; and 3) how much variation in
reproductive success and performanceacrossenvironmental-latitudinal gradients is due to variation in habitat
quality and how much to differential assortment of individuals among habitats (i.e., variation in individual
quality). The ecological and conservation implications of this research include providing a basis for
understanding how species may respond to large-scale changes such as global climate change and smaller
scale changes such as habitat loss and fragmentation.
Approach; I compare populations of two different species across their ranges: Tree Swallows in Ithaca, NY,
Lenoir City, TN, and Fairbanks, AK; European Starlings in Ithaca, NY, and Wellington, New Zealand. I
monitor reproduction as a function of body condition, quality of habitat and yearly survival. I manipulate
parental effort through brood size increases and decreases and examine how parents allocate resources
between themselves and their offspring. Parents and offspring are given mild immunochallenges to measure
immunocompetence. I conduct behavioral observations and measure nestling growth to determine parental
investment and nestling quality. These allocation decisions will be examined by comparing how individuals
of different body condition and in different locations respond to experimental manipulations of effort.
Status: I will compare my 1999 results from tree swallows with fieldwork in 2000 in Ithaca, 2001 in
Tennessee, and 2002 in Alaska. I will also be conducting research on Starlings in Ithaca in 2000 (plus 1999
data) and in 2000-2001 in Wellington, New Zealand.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915626
MANAGEMENT OF HAWAIIAN PRECIOUS CORALS
USING MOLECULAR GENETIC METHODS
Amy R. Baco-Taylor
University of Hawaii
Objectives/Hypotheses; The goal of my research is to examine the population genetic structure of three
species of precious corals, to determine the appropriate management units (or "stocks") for each of these
species. I will study eight precious coral beds in the Hawaiian Archipelago to address the following specific
hypotheses: 1) Beds of precious corals in the main Hawaiian Islands are genetically isolated units; 2) Rates
of gene flow differ between species and are correlated with life histories; and 3) Precious corals in the WesPac
"Refugium" do not supply sufficient propagules to replenish commercial beds of corals throughout the
Hawaiian Islands.
Rationale; By determining the stock structure of the harvested species and providing information on dispersal
and recruitment in these species as a function of life history, this project will elucidate the effectiveness of the
designated "Refugium" bed in the Northwest Hawaiian Islands for re-seeding exploited populations of precious
corals. This information will substantially improve our ability to manage the Hawaiian coral fishery as a
sustainable resource.
Approach: For each locality, 10-30 individuals will be sampled, representing both different islands as well
as different localities within islands. DNA will be extracted following methods of Romano and Palumbi
(1996). Microsatellite markers will be developed following established methods (Kijas, et al. 1994; Glenn,
1998), and intron markers following Palumbi (1996) and Villablanca et al. (1998). Genetic isolation will be
estimated using standard FST and Nem statistics with 95% confidence limits for each marker system: RST for
microsatellites (Slatkin, 1995) and KST for introns (Hudson, et al. 1992). Genetic differentiation will be
assessed both at the within island scale as well as between islands. Pairwise comparisons of populations will
be used to test: 1) how genetic differentiation varies by distance; 2) whether there is a directionality of
movement of propagules; and 3) whether adaptation to local environmental conditions is indicated.
Status; This project will compliment work I have almost completed studying the community structure,
succession, and evolution of organisms associated with whale falls in the deep sea. Since my whale-fall
research is close to completion, it will likely comprise the bulk of my dissertation. I have made significant
progress in two areas of my precious coral research: 1) collections; and 2) DNA marker development.
Presently, we are searching for additional variable microsatellite DNA markers to increase the number of useful
nuclear loci. I anticipate that in the next few months, I should have a series of markers for these corals species.
Papers & Publications; Baco, A.R., Smith, C.R., Peek, A.S., Roderick, O.K., and Vrijenhoek, R.C. 1999.
The phylogenetic relationships of whale-fall vesicomyid clams based on mitochondria! COI DNA sequences.
Mar Ecol Prog Ser 182:137-147.
Distel, D.L., Baco, A.R., Chuang, E., Morrill, W., Cavanaugh, C.M., and Smith, C.R. 2000. Do mussels take
wooden steps to deep-sea vents? Nature 403:725-726.
Williams, A.B., Smith, C.R., and Baco, A.R. 2000. New species of Paralomis (Decapoda, Anomura, Lith-
odidae) from a sunken whale carcass in the San Clemente Basin of southern California. J Crustacean Biol 20
Special Issue 2:282-285.
http://www.nurp.noaa.gov/corals.html, http://www.oar.noaa.gov/nurp/spotlite/spot_corals.shtml
10
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STAR Graduate Fellowship Conference
U915395
OPTIMAL COST-SHARING MECHANISMS FOR NONPOINT SOURCE
POLLUTION CONTROL
Kenneth A. Baerenklau
University of Wisconsin, Madison
Objectives/Hypotheses: To apply principal-agent theory to the problem of designing optimal cost-sharing
mechanisms for nonpoint source pollution (NPSP) control, and to test various theoretical mechanisms with
empirical data from agricultural producers in Wisconsin.
Rationale; Resource economists have developed a significant body of literature on the use of market-based
incentives to control NPSP, but have devoted far less effort to examining the use of voluntary cost-sharing
arrangements to accomplish this same goal. Considering the difficulties associated with NPSP control
problems, cost-sharing appears to have significant advantages over market-based approaches. But most of
the theoretical foundations of optimal cost-sharing mechanisms remain undeveloped. In particular, three
issues have yet to be addressed in the literature: 1) realistic objective functions and constraints—modeling
the actual problems faced by regulators; 2) dynamic incentives—allowing for additional contract offers if
previous offers have been rejected; and 3) agent heterogeneity—allowing for the possibility that "early
adopters" may exist but be difficult to identify.
Approach: Development of a theoretical model that addresses each of these three issues will be ac-
complished through original work in economic theory. This work will focus on accurately modeling the
problems faced by regulators who are constrained both by limited funding and by exogenous environmental
standards. Empirically testing variants of this model will require gathering relevant data from public agen-
cies and private landowners and developing an empirical model of agent behavior.
Status; A significant amount of information on Wisconsin's cost-sharing program has been collected
through interviews with state employees. Previously published theoretical and empirical models have been
examined and critiqued. Potential sources of empirical data have been identified and methods for collecting
this data are being finalized. A simple theoretical model of a cost-minimizing regulator faced with an
ambient standard has been developed and optimal solutions have been derived under various conditions.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915386
DIVERSITY OF EXPRESSED BIODEGRADATION GENES
Corien Bakermans
Cornell University
Objectives/Hvpotheses: To explore the diversity of naphthalene dioxygenase genes at a coal tar waste
contaminated field site and to determine the contributions of model organisms to naphthalene degradation
at the field site.
Rationale; Microbiologists have traditionally relied upon isolation and analysis of pure cultures to
determine the role of microorganisms in their environments. Unfortunately, it is becoming increasingly
evident that model organisms cannot describe the total breadth of capab ilities and types of organisms present
in complex microbial communities. We must then ask: do the capabilities of model organisms accurately
represent processes in water, sediment, and soils? Or more specifically, can all naphthalene degradation at
a contaminated field site be explained by the physiological activities of bacteria highly related to the model
organisms?
Approach; Both culture-based and molecular approaches wi I! be used to assess the diversity of naphthalene
dioxygenase genes at the field site in order to determine how method-specific biases can affect interpretation
of diversity. Naphthalene degrading organisms will be isolated from soil and groundwater samples. The
identity of their nahAc (if applicable) and 16S rDNA genes will be examined by PCR. In order to analyze
genes from currently unculturable organisms, nucleic acids will be extracted directly from site soil and water
and analyzed as above. The extraction of DNA will permit examination of the gene pool present; while
extraction of mRNA will enable analysis of active genes. A phytogenetic analysis of the genes will allow
a comparative analysis of organisms or genes obtained via the direct extraction and the cultivation
procedures. If sequences obtained using these two distinct procedures are not closely related, it may be
concluded that pure culture techniques were not adequate for assessing the diversity of naphthalene
dioxygenase genes in the field site. The contribution made by naphthalene dioxygenase (nahAc) alleles to
degradation of naphthalene at the field site will be assessed by identifying those organisms capable of
degrading naphthalene (using substrate specific direct viable counts [SS-DVC]) and that express nahAc
alleles (using fluorescent in situ hybridization [FISH]). Together, the two techniques can identify which
nahAc alleles are being used for naphthalene degradation at the site. The relationship of the model
naphthalene degrading organisms to the microbial community at the site will be determined through analysis
of 16S rDNA genes from total nucleic acids extracted from the groundwater. In addition, geochemical
analysis suggests that oxygen may not be the only electron acceptor used in naphthalene degradation at this
site. The contributions of various electron acceptor to naphthalene degradation at this site will be determined
through a series of microcosm experiments and analysis of the hydrogen partial pressure in the groundwater,
Status: Results indicate that molecular techniques reveal sequences divergent from the naphthalene
dioxygenase genes present in pure cultures of naphthalene degrading organisms isolated from the site.
SS-DVC revealed the presence of aerobic naphthalene degrading bacteria at the site and revealed that only
a small portion (0.3-4%) of the total community was involved in this response. Community analysis reveals
that cultured isolates consist of less than 1% of the total community and that oxygen may not be the primary
electron acceptor for naphthalene degradation at this site (also supported by geochemical data).
Papers & Publications; Bakermans, C. and Madsen, E.L. 2000. Use of substrate specific-direct viable
counts to visualize naphthalene degrading bacteria in a coal tar-contaminated groundwater microbial
community. J Microbiol Methods (submitted)
12
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STAR Graduate Fellowship Conference
Wilson, M.W., Bakermans, C., and Madsen, E.L. 1999. In situ, real-time catabolic gene expression:
extraction and characterization of naphthalene dioxygenase mRNA transcripts from groundwater. App
Environ Microbiol 65(l):80-87.
13
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STAR Graduate Fellowship Conference
U915341
PATH SELECTION BY RED SQUIRRELS (TAMIASCIURUS HUDSONICUS)
IN LOGGED FORESTS IN SOUTHEAST ALASKA
Victoria J. Bakker
University of California, Davis
Objectives/Hypotheses: My objectives are to: 1) determine the factors that influence path selection by red
squirrels (Tamiasciitrus hudsonicus) when traveling on unfamiliar ground in a logged region; and 2) identify
specific habitat features that facilitate movement for this species. I hypothesize that red squirrels will select
movement paths that minimize susceptibility to predation, reduce encounters with territorial conspecifics,
and increase speed of travel.
Rationale: In highly fragmented landscapes, gaps in forest coverage may restrict the movements of
forest-associated mammals among isolated forest patches. As a result, conservation biologists have
advocated protection of dispersal corridors as a way to connect forested reserves. Because we know little
about the factors that influence the movements of forest mammals when traveling on unfamiliar ground, I
am using a model forest mammal, the red squirrel, to investigate movement behavior. Understanding how
forest mammals select movement paths could help managers locate reserves and corridors and identify
matrix management practices that facilitate inter-reserve movement.
Approach; I am initially documenting territorial boundaries and behaviors of collared red squirrels living
in intact forests near forest gaps (clearcuts) in southeast Alaska. Subsequently, I am inducing movement in
these individuals by translocating them across forest gaps and releasing them. To test my hypotheses on
movement path selection, I am assessing squirrel homing routes at two spatial scales. First, I am using
simultaneous telemetry with two or more observers to document coarse-scale movements during the entire
homing journey, focusing on gap-crossing behavior. I am then characterizing these movements with a GIS
and using logistic regression analysis to relate landscape features (size and shape of forest gaps) to the
probability that squirrels cross gaps. Second, I am attaching tracking spools to squirrels to pinpoint fine-
scale (1-5 m scale) movements. I am measuring the characteristics of these fine-scale paths along with
paired random sample points in the field and using paired sample analyses to assess path selection.
Preliminary results suggest that the probability of squirrels crossing gaps is inversely related to the efficiency
of forested detours (ratio of gap-crossing distance to circumnavigating distance), indicating a trade-off
between presumably lower predation risk in forests and increased predation risk associated with spending
time on unfamiliar ground. Detour efficiency was a significant predictor of gap-crossing probability in a
logistic regression model, but neither the gap-crossing distance nor the quality of the squirrel's territory was.
At a fine scale, squirrels are choosing paths that permit rapid travel, favoring routes with a low slope and few
obstacles (i.e., low shrub stem density, low herb cover, extensive use of downed logs). They are also staying
close to trees, which they use as refuges. Squirrels are not selecting paths with high shrub cover, which
could conceal them from predators and conspecifics, but do appear to travel in areas with high shrub cover
relative to the number of movement obstacles present, again indicating a possible trade-off between
predation avoidance and travel time. These observations will be confirmed with additional data collection.
Status; I plan to collect data for a final field season from June to September 2000. I expect to complete my
degree by December 2001.
Paners & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915334
A NEW DIMENSIONLESS INDEX FOR STRUCTURAL HABITAT COMPLEXITY
Aaron Bartholomew
Virginia Institute of Marine Science
Objectives/Hypotheses; I devised a new dimensionless index of structural habitat complexity that
incorporates the size of the spaces within the habitat, and the size of the organism of concern. This index
is: the average inter-structural space size in the habitat divided by the linear measure of the organism that
would potentially limit its ability to move through the space (Sp/Pr).
Rationale; Structure can interfere with an organism's ability to move through a given habitat, depending
upon the size of the organism. This index I have devised is potentially applicable to all habitat types, and
since it is dimensionless, to all habitat scales. This potentially would allow researchers to better compare
results between studies. It also would allow managers to better measure what an "ideally complex" habitat
is for a given prey organism (i.e., a habitat where the prey can move through all of the spaces easily, but
which their [larger] predators cannot move through).
Approach; I repeatedly deployed five types of artificial seagrass plots in a seagrass bed, collected the plots
after one week, and counted, identified and measured the mobile fauna that had colonized the plots. The
treatments were: a control plot with no artificial seagrass, atreatment with 3.5 mm space sizes (high cover),
a treatment with 9.5 mm space sizes (med. cover), a treatment with 22 mm space sizes (low cover), and a
treatment with a third of each of the three space sizes (heterogeneous, med. cover overall). I grouped the
fauna into three categories: 0-3.5 mm wide, 3.5-9.5 mm wide, and 9.5-22 mm wide (>22 mm wide was very
rare).
Status; I am presently identifying and counting organisms. My initial analyses revealed that the smallest
size classes are responding as expected, and that the 3.5-9.5 mm size class colonized the heterogeneous
treatment in the greatest abundance.
Papers & Publications; Bartholomew, A., Diaz, R., and Cicchetti, G. New dimensionless indices of
structural habitat complexity: predicted and actual effects on a predator's foraging success. Mar Ecol Prog
Ser (in press)
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STAR Graduate Fellowship Conference
U915369
IMPACTS OF FLOW DIVERSION AND REGULATION ON SUCCESSIONAL
PROCESSES IN COTTONWOOD AND WILLOW DOMINATED RIPARIAN FORESTS,
VERDE RIVER, ARIZONA
Vanessa B. Beauchamp
Arizona State University
Objectives/Hypotheses; To determine how flow diversion and regulation alter natural successional pro-
cesses in cottonwood forests in a southwestern arid-riparian ecosystem. Findings from this study will be
used to develop restoration strategies and monitoring programs for cottonwood forests, to predict impacts
of water diversions on riparian forests, and to help dam managers develop water release schedules that will
enhance the quality of cottonwood forests downstream from dams.
Rationale; In the arid southwestern United States, riparian areas are important habitat for flora and fauna
unable to survive on the more xeric uplands. Rapid population growth in this region has resulted in flow
diversion, groundwater pumping, and dam construction to meet agricultural and urban water demands. This
has resulted in flow reduction, declining groundwater levels, and altered flow regimes that severely restrict
recruitment opportunities for cottonwood. While a substantial amount of work has investigated the impacts
of flow diversion and regulation on the trees themselves, few studies have assessed the effects of altered
hydrologic regime on understory vegetation, soil properties, or mycorrhizal populations, all of which are
critical components of this ecosystem type.
Approach; Because there is an age gradient of cottonwoods away from the active channel, a space-for-time
substitution approach will be used to investigate the changes in understory vegetation, soil texture, chemistry,
and mycorrhizae populations that occur along this gradient. A chronosequence of cottonwood stands ranging
from saplings to senescent trees will be used to examine these successional processes and assess how flow
diversion and regulation impact these processes.
Seven reaches along the Verde River have been selected for this study. Three reaches are free flowing: one
is subject to minimal surface water diversions, another is below a significant diversion, and a third lies above
the first reservoir on the Verde River. The next reach is below this reservoir, and the fifth reach is below
a second water storage reservoir. The remaining two study reaches are located above and below a large
unregulated tributary that may dampen some of the effects of flow regulation on the mainstem of the river.
Status; This project is in the beginning stages. Specific study sites will be established in summer and fall
1999. Reaches will be surveyed and trees will be aged in spring and summer 2000. Vegetation and soil
sampling will commence in fall 2000.
Pacers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915333
AIR POLLUTION AND HUMAN HEALTH
Michelle L. Bell
Johns Hopkins University
Objectives/Hypotheses: To investigate the possible climate change-driven effects of selected criteria air
pollutants (PM, O3) on human health, with a special emphasis on urban air quality. This research connects
global climate change to ambient air pollution concentrations, which are then linked to epidemiological
endpoints. Results will indicate how ambient air pollutant concentrations respond to different climatic
conditions and emission scenarios, and how human health could be affected by changes in air pollution
induced by global warming and emissions.
Rationale: Associations between air pollution and human health have been recognized for centuries.
Tropospheric ozone has been linked to a variety of acute and chronic effects including respiratory symptoms,
decreased lung function, and increased hospitalizations and emergency room visits. Paniculate matter has
been associated with acute and chronic morbidity and mortality such as premature mortality, hospital
admissions for respiratory illnesses, exacerbation of asthma, and decline in lung function. Air pollution is
likely to be affected by climate change through changes in emissions, exposure, transport, transformation,
precipitation, and possibly human behavior. For example, the formation of tropospheric ozone is tem-
perature dependent. This research explores the hypothesis that climate change can alter air pollutant
concentrations and that these alterations can have significant impacts on human health.
Approach; This research examines the potential relationships between climate change, selected urban air
pollutants, and associated human health effects by integrating remote-sensed data, mesoscale modeling,
epidemiological data and data analysis tools with downscaled climate change scenarios. This will include
the development of methodologies to link air pollution modeling and human health effects, which will have
applications beyond climate change. The Maryland/DC/Virginia/Delaware area will be used for a case study.
Several downscaled climate-change scenarios, representing a variety of climatic conditions, will be used as
input along with corresponding emissions fields and meteorological data to the Models-3/Community
Multi-Scale Air Quality modeling system, developed by the EPA National Exposure Research Laboratory.
This state-of-the-art model allows analysis of tropospheric ozone, particulate matter, and other pollutants
on a urban or regional scale, and will be used to evaluate the impact of different climatic and emission
scenarios on ambient air concentration fields (e.g., pollutant concentration's distribution, altered maxima
and minima, length of high O3 days, frequency of NAAQS violations, etc.). These air pollutant con-
centrations will be linked with results from selected epidemiological studies that estimate the effect of
changes in air pollutant concentration with human health endpoints. Various subgroup populations will have
different vulnerability to these health impacts; therefore, separate analysis will be performed for particularly
susceptible subgroups (e.g., the elderly, those with pre-existing respiratory conditions). Research will also
include uncertainty and sensitivity analysis.
Status; Models-3 and associated software have been installed. Three simulation runs have been completed
using Models-3 Tutorial data for 36 km, nested 12 km, and nested 4 km cell grids. Grid specification for the
study area has begun. Screening of epidemiological studies has begun.
Papers & Publications: None at this time.
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STAR Graduate Fellowship Conference
U915552
WATERSHED MODELING AND UNCERTAINTY ANALYSIS
OF THE CANNONSVILLE RESERVOIR BASIN
Jennifer Benaman
Cornell University
Objectives/Hypotheses: The goal of this project is to study sediment and phosphorous loadings from the
land surface to the Cannonsville Reservoir in Upstate New York. An additional objective is to investigate
the role of uncertainty in the calculation of these watershed loadings. The analysis will focus particularly
on spatial uncertainty, such as spatial distribution of rainfall data and topographical information.
Rationale; The Cannonsville Reservoir, which serves as a source of drinking water to New York City, has
been under a 'phosphorous-loading restriction' due to the high phosphorus concentrations within the water
body. These high concentrations are attributed to the non-point source loadings from the primarily
agricultural land in the basin. Currently, the county is attempting the implementation of Best Management
Practices (BMPs) in certain areas to abate this pollution problem. However, the county and regulatory
agencies need a way to evaluate the effectiveness of the BMPs. In addition, the engineers would like to have
a tool to project future conditions of the reservoir, given the possibility of certain land use practices and
BMPs, without having to fully implement the scenario 'real-time.' Inherent with this type of analysis is the
question of how much data needs to be collected to be statistically certain of the results—in other words, how
does uncertainty in data affect the analysis?
Approach; The approach of the evaluation of the BMPs and land use practices is to develop a basin-wide
watershed model for the Cannonsville Basin. The model simulates hydrology, sediment, and phosphorous
transport over the watershed, which ultimately becomes an input to the reservoir. The model being applied
is the Soil and Water Assessment Tool (SWAT), which was developed in Texas for use on agricultural lands.
This model, which will be combined with Geographical Information Systems (CIS), is spatially distributed,
requiring that the entire basin be divided into smaller sub-basins of similar land use, soil properties, and
topography. The model uses this information, along with meteorological data, river geometry information,
and constituent parameters to develop the fate and transport of phosphorus and sediment over the land
surface.
Status; A thorough literature review has been conducted and summarized in a draft report. In addition, the
data necessary to begin model development is being acquired from researchers and agencies. The model,
SWAT, has been obtained and the next steps will be to combine all of the data into a GIS database to develop
sub-basins and model input.
Papers & Publications; None at this time.
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U915569
COMMUNITY-BASED NATURAL RESOURCE MANAGEMENT IN MALI
Charles E. Benjamin
University of Michigan, Ann Arbor
Objectives/Hypotheses; The goal of this research is to develop a theoretical and methodological framework
for assessing the potentials and the limitations of community-based natural resource management [CBNRM]
strategies as a foundation for conservation and development. It integrates elements of ethnobotany, political
ecology, organizational theory, and environmental history to explore problematic dimensions of CBNRM
as a process. This research focuses on issues of local food security and biodiversity conservation in the West
African Sahel, particularly in the context of NGO-sponsored CBNRM projects in the Mopti region of Mali.
Rationale: Because of the generally poor success rate of top-down, technology-driven conservation and
development initiatives around the world, development policy-makers and practitioners have increasingly
come to recognize that the fundamental causes of environmental degradation are often intertwined with the
causes of rural poverty and with the political marginalization of rural populations. They have also learned
that effective conservation interventions must address the needs and circumstances of local users by building
upon their organizational, managerial and technical capacities. This growing awareness has meant that
organizations increasingly emphasize the participation of local people and the integration of local institutions
in conservation and development strategies. Throughout the West African Sahel, for example, political
reform at a national level and paradigm shifts among international aid organizations have come to favor
political decentralization in local governance and community participation in conservation and development
projects. These trends are often associated with the expansion of'civil society,' in the form of burgeoning
associative sectors, and with the proliferation of 'community-based natural resource management'
(CBNRM) projects under the auspices of international NGOs and donor agencies. Community-based
approaches seek to reinforce local capacity for natural resource management by building upon the social and
institutional capital of local resource users and by incorporating local ecological knowledge to increase local
investment in conservation and development. However, the performance of CBNRM projects has been
mixed, and the relevance of local populations and local institutions to conservation has recently come into
question. This research is designed to build a foundation for understanding the social and ecological
dynamics of local natural resource management, to contribute to the development and implementation of
more effective biodiversity conservation and food security programs.
Approach: The general approach of this research is to relate biophysical, social, and cognitive aspects of
human ecological interactions at a local level and then to situate these local interactions in progressively
wider historical and sociopolitical contexts. Inquiry will be based upon ethnographic fieldwork, in-
corporating qualitative and quantitative methods in several communities. Within this general framework,
data analysis will make use of several complementary lenses, each providing insight into different aspects
of human-environment interaction at different levels. These include cognition-based ethnobotany,
institutional analysis, organizational analysis, local histories from archival and oral sources, and geographic
information systems (GIS).
Status: I conducted preliminary research in the Kelka Forest of northern Mali from June through September
of 1999. I will return to that area in the summer of 2000 to establish a GIS protocol for monitoring
ecological change in the research area. Longer-term fieldwork will begin in February of 2001.
Papers & Publications: None at this time.
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U915152
STABILITY CONSTANTS FOR MERCURY BINDING WITH DOC ISOLATES
FROM THE FLORIDA EVERGLADES
Janina M. Benoit
The University of Maryland
Objectives/Hypotheses; Conditional stability constants for Hg binding with natural organic matter were
determined for two types of DOC isolated from surface waters of the Florida Everglades. The isolates
included hydrophilic and hydrophobic fractions from two distinct sites: Fl—an eutrophic, sulfidic site, and
2BS—an oligotrophic, low sulfide site.
Rationale; Dissolved organic carbon (DOC) has been implicated as an important complexing agent for Hg
that can effect it's mobility and bioavailability in aquatic ecosystems. However, stability constants for
natural Hg-DOC complexes are not well known. These constants will aid in the formulation of models
addressing Hg fate and transport in aquatic ecosystems.
Approach; We employed a competitive ligand approach to quantify stability constants for Hg with the DOC
isolates, called Fl-HPoA (hydrophobic fraction) and 2BS-HPiA (hydrophilic fraction). Our experimental
determinations utilized overall octanol-water partitioning coefficients (Dow) for Hg-203 at 10 mM chloride
and across pH and DOC concentration gradients ranging from 10-9 to 10-5 M. Use of radioisotope allowed
rapid determinations of Hg concentrations in both water and octanol phases without problems of matrix
interference. Stability constants for the two types of DOC were derived using basic thermodynamic
relationships, with a complexation reaction of the form: Hg2+ + RSH = HgRS+ + H+. Here the DOC is
modeled as a thiol, and a decrease in Hg binding with decreasing pH was expected.
Status; This work represents the fourth chapter of my dissertation. I expect to graduate in spring 2000.
Papers & Publications; Benoit, J.M., Gilmour, C.C., Mason, R.P., and Heyes, A. 1999a. Sulfide controls
on mercury speciation and bioavailability to methylating bacteria in sediments pore waters. Environ Sci
Technol 33:951-957.
Benoit, J.M., Mason, R.P., and Gilmour, C.C. 1999b. Estimation of mercury-sulfide speciation in sediments
pore waters using octanol-water partitioning and implications for availability to methylatingbacteria. Eviron
ToxicolChem 18:2138-2141.
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U915537
AMPHIBIAN DISPERSAL IN FRAGMENTED LANDSCAPES
Gayle L. Birchficld
University of Missouri
Objectives/Hypotheses: My objectives are to: 1) examine habitat use by frogs dispersing to/from breeding ponds
in fragmented landscapes, and 2) investigate habitat use by frogs displaced from their breeding site to unfamiliar
locations.
Rationale; Over the past 200 years, conversion of land for agricultural use, industrial development, and urban
sprawl have drastically reduced natural habitat for many North American species. Habitat fragmentation presents
a two-fold extinction risk in that reduced habitat decreases overall regional or metapopulation size, and increases
the degree of isolation between local populations. Increasing isolation leads to decreased migration between local
populations, lowering the likelihood ofrecolonization after extinction. Pond-breedingamphibiansprovideamodel
system for studying organisms in fragmented landscapes because they are dependent on wetlands for breeding and
development of aquatic larvae, yet they spend most of their adult life on land. There is very little information
about the terrestrial phase of the life cycle for most species, although a few investigators have conducted tracking
studies of amphibian dispersal to and from aquatic breeding sites. Because information about average dispersal
distance is lacking for most taxa, it is uncertain to what extent amphibians utilize the surrounding habitat.
Therefore, the effects of habitat fragmentation on amphibian populations are largely unknown. Basic information
about movement patterns and habitat use is necessary before the effects of habitat fragmentation can be assessed.
Approach: In the summer and fall of 1999,1 conducted radio-tracking in two populations of green frogs, Rana
clamitans, to examine post-breeding movement patterns and locate terrestrial overwintering sites. The first
population, located at the Baskett Wildlife Research Area in Boone Co., MO, breeds in a manmade pond
surrounded by essentially continuous second-growth deciduous forest. The second population is located in a more
fragmented landscape at the A. L. Gustin golf course in Columbia, near the University of Missouri campus. Here
the breeding pond is isolated from forested land by at least 100 m on all sides. In the summer of 2000,1 will use
radio-tracking and powdered fluorescent pigments to examine microhabitat use by frogs dispersing to breeding
ponds and by frogs displaced in the terrestrial habitat.
Status; Results from 1999 indicate that predation is significant among adults residing at the breeding pond.
Initially 15 frogs were captured and implanted with transmitters at each site in July. Additional frogs were
captured at both locations to replace frogs killed by predation for a total of 16 frogs tracked at the Baskett Area
and 23 at the golf course. At the Baskett area, 11 eleven frogs died and 5 were of undetermined fate (i.e.,
individual moved out of study area, was eaten by an organism that moved out of area, or transmitter failed). At
least three of the five survived until October, when, on the same day, their signals were undetectable. I suspect
that they had moved out of range, and over the next few days, selected overwintering sites from which I could not
detect their signal. At the golf course, of 23 frogs tracked, 7 survived until November, while 14 died and 1 frog's
fate was undetermined. Five frogs were tracked over 500 m from the breeding pond to Flatbranch Creek along
the northwest border of the golf course. A sixth frog that had not been located for several weeks was relocated
there later in the fall. High predation at the golf course may have been indirectly due to the unusually dry weather,
which prevented individuals from leaving the breeding pond until late in the summer. Isolated from woods, the
pond offered little protection from predators. Bullfrogs and snakes were documented predators in three and up
to six cases, respectively, while raccoons and aquatic turtles were suspected in some cases. Adult mortality data
in amphibians have generally been collected incidentally, and relatively little is known about predation rates in
adults for most species. This study suggests that predation can be significant, particularly if dispersal from the
pond is prevented by environmental conditions.
Papers & Publications; None at this time.
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U915223
INTRATROPICAL MIGRATION OF A LOWLAND PARROT:
IMPLICATIONS FOR CONSERVATION
Robin D. Bjork
Oregon State University
Objectives/Hypotheses; My hypothesis is that in seasonally dry, lowland tropical forests, there exist some
frugivorous, mature-forest obligate species that migrate seasonally in response to abundance of food
resources; that is, they migrate from regions of low fruit abundance to regions of higher fruit abundance.
In addition, I hypothesize that current protected area networks do not protect the annual habitat needs for
many of these intratropical migrants. My objective is to document habitat and spatial needs of a frugivorous
bird species associated with mature lowland tropical forest, a species that I predict will exhibit migratory
behavior, and to evaluate the status of habitat protection for the species relative to reserve design, reserve
management, and trends in habitat alteration across the landscape.
Rationale; In tropical forests, frugivorous birds stand out as candidate umbrella species for conservation
research and planning. Although the details of their movements are generally unknown, many species are
thought to migrate or engage in periodic regional, intratropical movements in response to spatiotemporal
patchiness in their fruit resources. The majority of information on this phenomenon comes from studies in
montane systems where birds migrate altitudinally as they track seasonal fruit availability along an
elevational gradient (Powell and Bjork, 1995). While it is recognized that the needs of altitudinal migrants
should be considered in regional conservation strategies in tropical montane systems, little is known about
intratropical migration in lowland systems and its application to conservation (Bjork and Powell, 1995).
Approach; This research is focused on a large-bodied, lowland frugivore, the Mealy Parrot (Amazona
farinosa) in Guatemala's Maya Biosphere Reserve, part of the largest contiguous area of lowland tropical
forest in Mesoamerica. I chose this focal species because I predicted it would exhibit the desired
characteristics (i.e., wide-ranging, forest specialist) and would have high conservation value as a model.
This species has a large geographic range (southern Mexico to Amazonia); hence, if it proves to be valuable
in regional conservation planning at one site, the species can be studied at additional sites to assess its utility
across a greater range of ecoregions. My strategy is to study Mealy Parrots year-round at the individual level
by tracking habitat and space use of radio-tagged adults and at the population level by examining their
distribution and abundance with the other five sympatric parrot species. The study site encompasses large
areas of contiguous forest and various degrees of human-altered forest landscape in order to assess effects
of landscape alteration on the species. Concurrently, I am monitoring the distribution and abundance of the
parrots' fruit resources—variables which could influence the birds' patterns and which may be impacted by
habitat alteration. I am using satellite imagery to develop a habitat map for the region and a Geographic
Information System for analysis across data layers including the habitat map, telemetry locations/home range
estimations, and land management boundaries in order to evaluate habitat protection for the species.
Status: Two of three years of field research have been completed in the Department of Peten, Guatemala,
including radio-telemetry with adult Mealy Parrots (1998: n=3, 1999: n=9), and monthly surveys of the
parrot community and of fruit abundance in replicated sites in four habitat types. For the 2000-01 field
season, my primary objective is to document annual space and habitat use patterns of up to 20 radio-tagged
Mealy Parrots across the Peten: in the northeast where we have focused the past two years of research and
in two new regions of the climatically different western Pet^n. Data on birds from the northeast will provide
analysis of interannual consistency of patterns at one site, whereas birds in the west will provide a test of
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consistency of migration patterns across a larger geographic region. Expected graduation is in December
2001.
Papers & Publications; Bjork, R. Efectos de la alteracion del bosque tropical sobre el uso espacial y
temporal del habitat por el Loro Real (Amazonafarinosa) en la Reserva Biosfera Maya, Peten, Guatemala.
Paper presented in Spanish at the Mesoamerican Society of Biology and Conservation in Guatemala City
in July 1999.
Bjork, R. Effects of habitat alteration on Mealy Parrots in Guatemala: a landscape perspective. Paper
presented at the VI Neotropical Ornithological Congress in Monterrey, Mexico, in October 1999.
Bjork, R. Migraciones locales del Loro Real, Amazonafarinosa, en El Peten, Guatemala: consecuencias para
la planificacion de la conservacion regional. Paper presented in Spanish at the meetingNuevas Perspectivas
de Desarrollo Sostenible en Peten in Flores, Guatemala, in December 1999. Publication by the same name
is in press in the proceedings from the workshop. The workshop was organized by the National Council for
Protected Areas (CONAP) and the Latin America Faculty of Social Sciences (FLACSO) to facilitate
communication among scientists who are working in the Department of Peten, Guatemala, and identify
priorities for future research.
Bjork, R. and Powell, G.V.N. 1995, Buffon' s Macaw (Ara ambigud): some observations on the Costa Rican
population, its lowland forest habitat and conservation. In: Abramson, J., Speer, B.L., and Thomson, J.B.,
eds. The Large Macaws. Fort Bragg: Raintree Publications, 1995:387-393.
Powell, G. V.N. and Bjork, R. 1995. Implications of intratropical migration on the design of protected natural
areas: a case study using Pharomachrus mocinno. Conser Biol 9:354-362.
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U915661
MECHANISMS OF PHYTOREMEDIATION
AND CONSTRUCTED WETLANDS ENGINEERING
Diane L. Bondehagen
Florida International University
Obiectives/Hvpotheses; To demonstrate and quantify the potential of aquatic plants in assimilating
nutrients, metals, and toxic organics considering the engineering management of constructed wetlands. The
goal is to address the diversity and complexity of technical issues involved including geochemistry, biology,
and hydrogeology, and through field work demonstrate empirical and theoretical aspects of cost-effective
wetlands engineering.
Rationale; Wetlands are increasingly important for wastewater treatment because of the ability of many
wetlands plants to sorb large amounts of nutrients and toxic substances. Not only aquatic vascular plants
but also aquatic bryophytes and algal species have been shown to be useful for sorption and uptake for water
treatment. Ultimately, this uptake depends on the nature and amount of the biomass, the nutrient or toxic
substance to be removed, and other factors such as competing ions, metal concentrations, and the geological
substrate. Also, selection of an optimal plant species depends on the ease of growth of the plant, the yield
of biomass, ease of harvest, and disposal considerations.
Approach; The research plan will involve both laboratory/bench-scale microcosms and field-scale
mesocosms to investigate phytoremediation pollutant removal mechanisms and assess process efficiencies.
In order to get a correct and effective interpretation of biomonitoring results, several studies will be carried
out to determine uptake/release kinetics. Environmental factors including illumination, temperature, and
other physio-chemical characteristics will be analyzed. A mass balance approach will be used to determine
removal amounts; harvesting rates and loading will be monitored and examined.
Status; An extensive literature review is being conducted. Initial laboratory work was performed using
Eichhornia crassipes, Pistia stratoites, Brassicajuncea, and Medicago sativa to examine metal removal
kinetics.
Papers & Publications: Cardenas, R., Bondehagen, D., and Laha, S. Rhizofiltration for the removal of
metals from wastewater. Proceedings of ASCE Florida, Annual Meeting, September 1999.
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U915590
A BAYESIAN PROBABILITY NETWORK APPROACH TO PREDICTIVE MODELING
IN SUPPORT OF ENVIRONMENTAL DECISION MAKING
Mark E. Borsuk
Duke University
Objectives/Hypotheses; To demonstrate that probability network models represent an improved approach
to predictive modeling used for environmental management.
Rationale; The probability network method has the potential to remedy many of the traditional short-
comings of science used for decision-making. The method is probabilistic in its approach, which facilitates
a meaningful communication of uncertainty, is consistent with the risk assessment paradigm, and allows
decisions to be made based on expected values. By incorporating expert judgment, the method is not
paralyzed by a lack of observational data. In addition, the assessment endpoints are chosen so that they are
of vital interest to stakeholders and decision-makers and can be easily conceived in terms of utility for use
in formal decision analysis.
Approach: A probability network model is being developed and applied to the problem of eutrophication
in the Neuse River, USA. Also called a Bayesian probability network, or a "Bayes net," this model consists
of the set of variables of interest in the system being modeled as well as a set of assertions concerning the
probabilistic relationships among the variables. These relationships are quantified using historical data,
models, and expert judgment. Probabilistic predictions of model endpoints are then made that are based on
the entire set of conditional probabilities that have been assessed for each system variable. Not only does
this network structure provide a more integrated approach to uncertainty analysis, but it also allows easy
updating of prediction and inference when observations of model variables are made. This capability is
particularly important when applied to a natural system in which additional monitoring is likely to occur
concurrent with the modeling effort.
Status: The overall structure of the model has been developed and many of the relationships between
variables have been quantified. Tasks that remain include: to extend the model's predictions to ecological
endpoints, to test the model's predictive ability, and to evaluate alternative management scenarios.
Papers & Publications; Borsuk, M.E., Stow, C.A., Higdon, D., and Reckhow, K.H. 2000. A Bayesian
hierarchical model to predict benthic oxygen demand from internal and external organic matter loading in
estuaries and coastal zones, (in preparation)
Qian, S.S., Borsuk, M.E., and Stow, C.A. 2000. Seasonal and long-term trend decomposition along a spatial
gradient: an application to nutrient data in the Neuse River watershed, (in review)
Borsuk, M.E., Stow, C.A., Luettich, R.A., Jr., Paerl, H.W., Pinckney, J. L. 2000. Modeling oxygen
dynamics in an intermittently stratified estuary: estimation of process rates using field data, (in review)
Stow, C.A., Borsuk, M.E., and Stanley, D.W. 1999. Long-term changes in watershed nutrient inputs and
riverine exports in the Neuse River, North Carolina, (in review)
Stow, C.A. and Borsuk, M.E. 2000. Examination of long-term nutrient data in the Neuse River watershed.
Water Resources Research Institute of the University of North Carolina report, (in press)
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Borsuk, M.E., Clemen, R.T., Maguire, L.A., and Reckhow, K.H. 1999. Stakeholder values and scientific
modeling in the Neuse River watershed. Group Decision and Negotiation, (in revision)
Borsuk, M.E. and Stow, C.A. 2000. Bayesian parameter estimation in a mixed-order model of BOD decay.
Water Res 34:1830-1836.
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U915643
ESTROGEN-REGULATED GENE EXPRESSION IN LARGEMOUTH BASS
(MICROPTERUS SALMOIDES)
Christopher J. Bowman
University of Florida
Objectives/Hypotheses: My overall objective is to characterize differential effects on the primary and
delayed primary molecular response to different types of estrogen-like chemicals. Specifically, I would like
to profile the gene induction of estrogen receptor (ER) and vitellogenin (Vtg) to estradiol (E2),
ethinylestradiol (EE2), and methoxychlor (MXC) with respect to dose and time. My overall hypothesis is
that E2, EE2, and MXC will exhibit different characteristic transactivational primary and delayed primary
responses because of the ligand-dependent variation on mRNA stability and half-life.
Rationale; Scientific, political, and social issues surrounding hormonally active agents (HAAs) has led the
United States to amend the Safe Drinking Water Act (PL 104-182) and the Food Quality Protection Act (PL
104-170) to require testing of xenoestrogens. Due to the complex and unknown nature of how these
chemicals may or may not be impacting biosystems, research into possible specific mechanisms of action
is important. When trying to establish cause and effect in environmental hormone disruption, one of the
missing links is hormonal mechanisms of gene activation in vivo. Historically, the estrogenic response is
the best understood pathway of disruption to HAAs. Therefore, my proposal to study the impact of EE2 and
MXC on ER-mediated gene expression will serve to explain subtle mechanisms underlying the complex
regulation of the estrogenic response when challenged by environmental chemicals. By studying the
regulation of Vtg and ER gene induction at the mRNA and protein level it is possible to learn more about
the establishment of complex gene networks in an intact, environmentally-relevant system in vitro and in
vivo.
Approach; I plan to test my hypothesis in vitro and in vivo. I will need to clone and sequence cDNA
fragments to the ER and Vtg genes in Largemouth bass (LMB). The in vitro approach encompasses the
development, characterization, and validation of a LMB primary hepatocyte model. Once this tool is
developed, I plan to characterize dose and time response for Vtg and ER mRNA induced by E2, EE2, and
MXC. This will be followed by Vtg protein analysis. Similar experiments examining dose and time res-
ponse will also be conducted in vivo to compare cell-specific responses to that seen in the whole animal.
These comparisons will be made at the mRNA level of the ER and Vtg genes, followed by Vtg protein
accumulation. Then, I would like to study the transcription rates and mRNA stability of Vtg mRNAs with
different chemical exposures in the primary hepatocyte culture system.
Status; Thus far, I have cloned and sequenced cDNA fragments to the LMB ER and Vtg genes. These
clones have been used to characterize and quantitate these mRNAs by Northern and Slot blot analysis. I have
conducted two in vivo injection experiments. The first was a time course response to E2-injection. The
second was a dose response to E2, EE2, and MXC. Both experiments are to be analyzed for Vtg and ER
mRNA, as well as plasma Vtg and steroids. The first experiment has been completed and the samples from
the second experiment are still being analyzed. In addition, intact hepatocytes have been consistently iso-
lated from LMB and culture conditions have almost been optimized. Validation of cell type and
characteristics have been done using light microscopy, dye-exclusion, and electron microscopy. I plan to
complete the dose response profiles of Vtg mRNA and protein to estrogens using this in vitro system this
year.
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Papers & Publications; Bowman, C.J., Kroll, K.J., Hemmer, M.J., Folmar, L.C., and Denslow,N.D. 2000.
Estrogen-induced vitellogenin raRNA and protein in sheepshead minnow (Cyprinodon variegatus).
(submitted)
Folmar, L.C., Hemmer, M., Hemmer, R., Bowman, C., Kroll, K., and Denslow, N.D. 2000. Comparative
estrogenicity of estradiol, ethynyl estradiol and diethylstilbestrol in an in vivo, male sheepshead minnow
(Cyprinodon variegatus), vitellogenin bioassay. Aquatic Toxicol 49:77-88.
Bowman, C.J. and Denslow, N.D. 1999. Development and validation of a species- and gene-specific
molecular biomarker: vitellogenin mRNA in largemouth bass (Micropterus salmoides). Ecotoxicol
8:399-416.
Denstow, N.D., Bowman, C.J., Robinson, G., Lee, S.H., Ferguson, R.J., Hemmer, M.J., and Folmar, L.C.
1999. Biomarkers of endocrine disruption at the mRNA level. In: Henshel, D.A., Black, M.C., and Harrass,
M.C., eds. Environmental Toxicology and Risk Assessment: Standardization of Biomarkers for Endocrine
Disruption and Environmental Assessement: ASTM STP1364. American Society for Testing and Materials,
West Conshohocken, PA, 8:24-35.
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U915399
COMMUNITY INTERACTIONS THAT AFFECT NUTRIENT DYNAMICS
IN SALT MARSHES: LESSONS FOR HABITAT RESTORATION
Katharyn E. Boyer
University of California, Los Angeles
Objectives/Hypotheses; To gain understanding of how complex community relationships in coastal salt
marshes affect nutrient dynamics, and to use this understanding to improve habitat restoration and pollution
management.
Rationale; Recent studies suggest that the relative importance of competition and facilitation in structuring
ecological communities is shifted towards positive interactions in stressful environments such as salt
marshes. However, nutrients are often limiting to estuarine plants and algae, and competition for nutrients
within the community is likely to be great. Further, nutrient cycling involves multiple trophic levels, and
organisms that mediate exchanges of nutrients may play an important role in the distribution and abundance
of primary producers. Despite the potential importance of community interactions on resources that affect
productivity, little attention is devoted to these interactions when restorationists attempt to replicate natural
systems.
Approach: I am examining the interactions of four groups of organisms in the low to mid-intertidal zone
of southern California salt marshes: vascular plants, macroalgae, microalgae, and epibenthic invertebrates.
In a series of field and greenhouse experiments, I am assessing the relative importance of representatives
within these groups on nutrient partitioning within the biotic and abiotic compartments of the community.
Experiments include the use of isotope labeling techniques to trace the fate of nutrients. Greenhouse
experiments utilize a tidal simulator and a flow-through seawater system in individually-plumbed
experimental units.
Status; I have completed a field experiment in which I enclosed portions of a constructed salt marsh and
examined the relative contribution of two common epibenthic invertebrates to nutrient partitioning and plant
and algal production. One completed greenhouse experiment examined nutrient and organic matter
exchanges between macroalgae and sediments from constructed and natural marshes. In another greenhouse
experiment, I am currently assessing nutrient interactionsbetweenmacroalgae, constructed marsh sediments,
and vascular plants.
Papers & Publications; Boyer, K.E. and Zedler, J.B. 1999. Nitrogen addition could shift plant community
composition in a restored California salt marsh. Restor Ecol 7:74-85.
Boyer, K.E. and Zedler, J.B. 1998. Effects of nitrogen additions on the vertical structure of a constructed
cordgrass marsh. Ecol Appl 8:692-705.
Boyer, K.E. and Zedler, J.B. 1996. Damage to cordgrass by scale insects in a constructed salt marsh: effects
of nitrogen additions. Estuaries 19:1-12.
Fong, P., Boyer, K.E., and Zedler, J.B. 1998. Developing an indicator of nutrient enrichment in coastal
estuaries and lagoons using tissue nitrogen content of the opportunistic alga, Enteromorpha intestinalis (L.
Link). J Exper Marine Biol Ecol 231:63-79.
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Fong, P., Boyer, K.E., Desmond, J.S., and Zedler, J.B. 1996. Salinity stress, nitrogen competition, and
facilitation: what controls seasonal succession of two opportunistic green macroalgae? J Exper Marine Biol
Ecol 206:203-221.
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U915224
HOST FIDELITY AND APPARENT COMPETITION IN HOST-PARASITOID SYSTEMS
Chad E. Brass!!
University of Maryland
Objectives/Hypotheses; The goal of this research is to understand the possible dynamics of a two host, one
parasitoid system in which the parasitoid preferentially searches for hosts on plants from which it emerged.
This research will be conducted at both the theoretical level and the laboratory level. Many ecological and
evolutionary aspects will be considered including indirect effects between hosts and maintenance of
biodiversity.
Rationale: In atwo-host-one-parasitoid system, apparent competition can result in the extinction of one of
the hosts. Theoretically, apparent competition in this case forces the extinction of the less fecund host. Holt
and Lawton (1993) suggest that a major question driving ecological work should be "What mechanisms
permit the coexistence of several host species confronted by biologically oligophagous and polyphagous
parasitoids?" A number of possible mechanisms may stabilize a parasitoid system: donor-control, host
density dependence, host switching, spatial refuges, and temporal refuges. Recent research has shown that
host fidelity will also stabilize the system. By host fidelity, I mean that parasitoids may preferentially search
out hosts growing on plants from which the parasitoid emerged. In a large world of diverse foliage, this may
increase their chances of finding a suitable host.
Increasing evidence suggests that plants play a large role in host-parasitoid dynamics. At least some
parasitoids use green leaf volatiles emitted by plants to locate plant patches which may contain preferred
hosts. Evidence suggests that plants may increase green leaf volatiles upon leaf damage, further drawing
parasitoids to their host. Parasitoids learn these plant cues, or other chemical cues from the host, upon
emergence as adults. Simple models have shown that this host fidelity provides a theoretical mechanism for
the stabilization of the two-host-one-parasitoid system. All of these theoretical predictions may change
somewhat under evolutionary dynamics, producing counter-intuitive results.
Approach; I will be extending the models of host fidelity to include more empirical realism. For example,
a searching parasitoid that fails to find a host on the plant type on which it is searching will begin to search
on all plant types. This empirical reality could profoundly effect the results of the model. Simulations are
conducted using a combination of Mathematica and C++.
At the same time, I am developing populations in the laboratory that will allow me to test my theoretical
predictions. Laboratory studies, in this case, are viewed as an intermediate step to full understanding of
natural systems. My laboratory studies will be conducted using Plodia interpunctella and another stored
product moth along with a well studied parasitoid such as Venturia canescens. The three species will be
established in cages with a dividing mesh that allows the parasitoid to move back and forth without allowing
the moths to directly interact. The stored product on which the larvae are feeding, be it wheat, oats, or corn,
can be easily manipulated to study the populations dynamics of the system in a controlled, replicated setting.
Status: I am continuing my thesis research as I develop these models and establish the laboratory
populations.
Papers & Publications; Brassil, C.E. Mean time to extinction of a metapopulation with an Alice effect.
Ecol Modelling (in press)
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STAR Graduate Fellowship Conference
U915600
A MODEL FOR ECOSYSTEM MANAGEMENT THROUGH LAND-USE PLANNING:
UNDERSTANDING THE MOSAIC OF PROTECTION
ACROSS ECOLOGICAL SYSTEMS IN FLORIDA
Samuel D. Brody
University of North Carolina, Chapel Hill
Objectives/Hypotheses: To develop a model for ecosystem planning and to examine local plans as a tool
to manage selected ecological systems in Florida.
Rationale; Resource managers and planners in the United States are embracing the emerging paradigm of
ecosystem management. While much research and policy efforts have been geared toward instituting the
broad principles of managing natural systems, comparatively little work has been done to evaluate the
specific tools and strategies involved in implementing ecosystem management strategies at the local level.
The results of this study will increase understanding of how and exactly where to incorporate ecosystem
management most effectively into local level resource planning decisions. They will not only advance the
theory on what constitutes a quality environmental plan, but by using Geographic Information Systems
(GIS), the findings will also provide guidance for both local and regional planners on where to set future
policies to reduce the decline of biological diversity.
Approach: A detailed protocol will be developed based on established planning theory that will be used
to evaluate the ability of a plan to implement ecosystem management principles. Once ecosystem
management plan quality is measured, the following methods of analysis will be employed to quantitatively
and qualitatively address the research problem: 1) A random sample of plans and associated planning
processes will be taken and evaluated against the plan quality protocol. Statistical analyses will be conducted
to determine the effectiveness of comprehensive plans in achieving ecosystem management and what factors
contribute to a high quality plan. A survey will measure planning process variables, including commitment
to ecosystem planning, representation of specific stakeholders, and the types of participation methods used.
GIS analysis will be used to measure environmental variables, such as the amount of biodiversity/critical
habitat and threat to habitat to determine their influence on plan quality. 2) Twelve of the established 24
ecosystems throughout the state of Florida will be selected for more detailed analysis. Ecosystem
management plan quality for county jurisdictions and major cities will be evaluated across ecosystem
management areas (EMAs) in the southern portion of the state. The plan quality of each jurisdiction will
be statistically measured based on the plan quality protocol and then mapped (using GIS) as an overlay on
top of the ecosystem, areas of high biodiversity, and recommended areas for conservation. With this
technique, the mosaic of protection can be spatially and statistically analyzed for specific ecosystems.
Spatial associations for comprehensive plan scores within ecosystems will also be examined to understand
the impacts of location on plan quality and ecosystem protection. 3) Several ecosystems in southern Florida
will be selected to further understand the factors contributing to effective ecosystem management. Case
studies will complement prior phases of the research project by investigating statistical findings in further
detail.
Status; A pilot study based on 24 local jurisdictions has been conducted to test the plan evaluation protocol
and GIS measurement techniques, and make initial statistical conclusions about the ability of local
jurisdictions to manage ecological systems.
Papers & Publications: None at this time.
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STAR Graduate Fellowship Conference
U915374
PHOSPHORUS DYNAMICS IN A TIDAL OLIGOHALINE MARSH: IMPLICATIONS
OF SULFATE AND TIDAL INFLUENCE
Jeanna R. Bryner
University of Maryland Center for Environmental Science
Objectives/Hypotheses: To determine the effects of sulfate and tides on the behavior of phosphorus in
fresh/oligohaline marsh systems.
Rationale: Sulfate has come to the forefront as a significant mechanism controlling P-release from
sediments in lake and marine systems. However, in tidal fresh/oligohaline marshes, there is no clear
understanding of the importance of sulfate and other factors in controlling P-dynamics. Tidal marshes must
be examined, because: 1) they differ from these deep water habitats in terms of hydrology, input of sediment
and nutrients, macrophyte biomass, and redox conditions, and 2) atmospheric pollution and sea-level rise
can increase sulfate in freshwater environments.
Approach: To examine the controls of P-retention, sulfate was added to fertilization plots set up at the river
bank and interior of King's Creek marsh, located on the Choptank River, a subestuary of the Chesapeake
Bay. Through measurements of pore water nutrients, solid phase P, iron, and iron-sulfides, the effect of
sulfate on P-dynamics was determined. Although fertilization was unsuccessful, the effects of sulfate and
tides on the P-cycle were still ascertained.
Status: Sediment cores are being taken in other marsh systems along the salinity gradient of the Choptank
River to test the validity of trends for phosphate release found.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915407
NITROGEN CYCLING IN A SHALLOW COASTAL LAGOON:
ROLE OF PHOTOCHEMISTRY
Ishi D. Buffam
University of Virginia
Objectives/Hypotheses; This study is the first step in a larger proposed project, whose goal is to place
photodegradation into a whole-system model of nutrient (C and N) cycling in Hog Island Bay (HIB),
Virginia, and compare the relative importance of nutrient fluxes due to photochemistry with other nutrient
flux rates in shallow coastal waters. The present study seeks to address the following hypotheses: 1) UV
light has a measurable effect on the concentration of nitrogen containing compounds in HIB water, and an
increase in incident UV light would alter N-cycling rates in the water column; 2) sources of organic matter
to HIB vary in their photochemical liability with respect to release of nitrogen-containing compounds; and
3) photochemical degradation has a potentially significant ecological role in nitrogen cycling in HIB water,
due to altering the concentrations of bioavailable nitrogen.
Rationale: The natural photochemical degradation of aquatic organic matter releases carbon by conversion
to inorganic forms, and changes in the level of incident high-energy UV radiation may alter the magnitude
of this photodegradation process. If inorganic nitrogen or small organic bioavailable N species also are
released at significant rates by photodegradation, this could affect the productivity of N-limited coastal
systems. An understanding of the role of photochemical oxidation in shallow coastal waters will enable us
to more confidently predict the effects of increases in incident UV light or changes in water column turbidity
on productivity and nutrient cycling in similar coastal ecosystems.
Approach; Utilizing a laboratory assay with controlled light levels, photochemical release rates are
determined for bioavailable nitrogen species in a range of water samples including groundwater, stream-
water, seawater and leachate from marsh macrophytes and lagoon macroalgae. These samples represent
allochthonous and autochthonous organic matter sources to HIB, a shallow coastal lagoon on the eastern
shore of Virginia that is thought to be N-limited. Upon collection, water samples are sterilized and incubated
in quartz containers for one week while being subjected to treatments of artificial UVA (320-360 nm) or
UVB (280-320 nm) light, with samples incubated in the dark as aphotic controls. The irradiance level and
wavelength of the UVA treatment mimics that of natural sunlight, while the UVB treatment simulates
harsher, more high-energy light levels that might occur following significant stratospheric ozone depletion.
Total nitrogen, ammonium, nitrate, urea and amino acid concentrations determined before and after
irradiation are used to calculate rates of DON degradation and concomitant release of bioavailable nitrogen.
Status; A summer 1999 experiment with Hog Island Bay surface water incubated in situ at 20 cm below
the water surface resulted in unmeasurable changes in the concentrations of DON, NH4, NO3 and urea,
suggesting that photodegradation has little impact on N-cycling for aged DOM in the water column. In the
present experiment, I am using "fresh" DOM sources, which have not been recently exposed to sunlight, and
am exposing them to irradiance conditions that more closely mimic the water surface where most photo-
degradation is expected to occur.
Papers & Publications; Buffam, I.D., McGlathery, K.J., and Galloway, J.N. 2000. Photochemical release
of inorganic nutrients from dissolved organic matter in a coastal aquatic system. Paper presented at the
American Society of Limnology and Oceanography Conference, Copenhagen, Denmark, June 5-9,2000.
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STAR Graduate Fellowship Conference
U915178
DOCUMENTING CHANGES IN CUSTOMARY MARINE TENURE: A CASE STUDY
OF AN OUTER ISLAND GROUP IN FIJI
Mark A. Calamia
University of Colorado, Boulder
Objectives/Hypotheses; Throughout the Pacific, the collapse of indigenous sea tenure regimes is attributed
to a shift from subsistence to commercial fishing and the use of more efficient gear. At present, Fiji is in the
process of redefining customary marine tenure as new opportunities develop for the commercialization of
inshore marine waters. One area where this is occurring is in the outer island group of Kadavu where the
collection of sea cucumbers, commercial fishing, dive tourism, and marine protected areas are all viewed
by villagers as alternatives to fishing for generating cash income. This study explicates how indigenous sea
tenure regimes (traditional ownership of inshore marine waters) in an outer island group of Fiji are changing
because of the recent introduction of dive tourism and development of community-based marine protected
areas. Additionally, the role of non-traditional fishing methods, such as the use of scuba gear for sea
cucumber collection, will be explored in light of local economic pressures that present obstacles in the
development of sound traditional and non-traditional management practices.
Rationale; (Not received at time of printing.)
Approach; Various ethnographic techniques, including interviews and participant observation have served
as the primary basis for qualitative data collection. Semi-structured interviews, informal in-depth recorded
interviews, participatory rural appraisal methods, and household economic surveys were designed to gather
data on resource use, local ecological knowledge, social organization, fishing techniques, and household
income and expenditure. Active participant observation of fishing techniques and dive tourism events was
conducted to learn how various practices impacted the local resource base. Household economic data and
catch per unit effort data were collected from 13 villages from two traditional fishing grounds. A GPS was
used together with aerial photography to locate and map customary fishing spots and boundaries of clan
fishing grounds. Spatial analyses will be performed on these data to identify the accuracy by villagers in
locating these features at sea. Socioeconomic and catch per unit effort data will be analyzed using a one-way
ANOVA to show variability between the two major fishing grounds. Content analyses of narratives will be
performed with specialized text software.
Status; (Not received at time of printing.)
Papers & Publications; Documenting changes in customary marine tenure. PASIFIKA. September/
December 1999: 4-5.
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STAR Graduate Fellowship Conference
U915544
SUBMERGED AQUATIC PLANT COMMUNITY DYNAMICS
Robert S. Capers
University of Connecticut
Objectives/Hypotheses; I have been studying a community of submerged plants in a freshwater tidal
wetlands on the lower Connecticut River for 4 years, characterizing the community and studying the degree
of change that occurs naturally. I now am beginning to investigate the importance of competition and
disturbance and the means by which species colonize newly available space, whether by seed bank,
vegetative growth, fragmentation or winter buds. I also will characterize the plant community in terms of
chemical and physical conditions, using ordination. Models developed in one cove then will be tested for
usefulness across a range of increasingly distant and ecologically different wetlands.
Rationale: Riverine wetlands are important ecosystems, serving as habitat for rich vertebrate and
invertebrate communities, including fish, birds, mammals, molluscs, crustaceans, and insects. Submerged
plants are an essential component of these ecosystems, stabilizing sediment, regulating nutrient cycling, and
providing substrate or habitat for the rich faunal communities. In spite of their importance, aquatic
ecosystems are much less well studied than their terrestrial counterparts. They also are increasingly
threatened: freshwater wetlands worldwide are being destroyed at a rate that may exceed the rate of
destruction of tropical forests.
Approach; I will use both transplant experiments and removal experiments to establish the effects of
competition among dominant species. Sediment samples have been obtained to study the importance of the
seed bank, and plants will be removed from selected areas of the wetland to determine how species colonize
newly available habitat. Paired quadrats will be selected for disturbance experiments, and exclosures will
be constructed to determine the effect of grazing by waterfowl. I will use multiple regression analysis to
establish the affinity of species for particular chemical and physical conditions and will use Detrended
Correspondence Analysis and Canonical Correspondence Analysis to characterize the community in terms
of these conditions. The ordination and regression results then will be used to predict the performance of
submerged species in other wetlands, and the predictions will be tested by sampling in increasingly different
wetlands.
Status: Recording of data on the degree of annual change is continuing in five wetlands. Seed-bank and
colonization studies are underway. Sediment and water chemistry analysis and community ordination will
be done in the fall. Competition studies are planned in 2001.
Papers & Publications: Capers, R.S. A comparison of two sampling techniques in the study of submersed
macrophyte richness and abundance. Aquatic Botany (in press)
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STAR Graduate Fellowship Conference
U915433
AN ANALYSIS OF LEGAL AND REGULATORY MECHANISMS TO CONTROL
INTERSTATE OZONE TRANSPORT
Christina C. Caplan
University of California, Berkeley
Objectives/Hypotheses; To assess the adequacy of the various legal and regulatory mechanisms used by
the U.S. Environmental Protection Agency (EPA) and the Northeastern states to address the growing
problem of interstate transport of ozone pollution, and to propose an alternative means to solve the problem.
Rationale; Nitrogen oxides (NOX) are emitted as a byproduct of the combustion of fossil fuels, primarily
by vehicles, power plants, and industrial boilers. In addition to contributing to acid rain, NOX emissions react
with hydrocarbons in the presence of sunlight to form ground-level ozone. Ozone is associated with adverse
health and environmental effects and is one of the pollutants regulated by a national ambient air quality
standard (NAAQS) under the Clean Air Act (CAA). Ozone is also subject to long-range transport, which
has recently fueled a sharp controversy within the eastern half of the United States. Emissions of NOX from
coal-fired utilities in the Midwest have been transported to states in the Northeast, which are facing
significant ozone nonattainment problems in large part because of this transport. The transport problem has
been exacerbated by a current loophole in the CAA that exempts older coal- and oil-fired power plants from
meeting new source performance standards (NSPS), which set strict pollution control requirements. The
loophole has unfortunately created an economic incentive for utilities to keep older, dirtier facilities in
operation much longer than would otherwise have occurred. As a result, these facilities have generated
significant amounts of NOX pollution and contributed to the ozone transport problem. Because of the
stringent sanctions under the CAA that face states unable to attain the ozone NAAQS, the Northeast—with
the help of EPA—has desperately attempted to use all means possible to force the Midwest utilities to reduce
their NOX emissions and to stop the ozone transport.
Approach; This paper will analyze and determine the effectiveness of the various legal and regulatory
mechanisms available under the CAA to address interstate ozone transport. These mechanisms include
regional transport commissions established both under the CAA and voluntarily by the states; EPA authority
to require states to revise their state implementation plans to better address interstate pollution transport;
state petitions to EPA for a finding that sources in other states are affecting their ability to attain the NAAQS;
voluntary negotiations; federal enforcement actions; and citizen suits under the CAA. The paper will assess
the various limitations of these mechanisms and recommend more effective alternative means to address
interstate ozone transport.
Status; Research and paper completed.
Papers & Publications; Paper to be published in Ecology Law Quarterly (December 2000).
AAMA v. Massachusetts Department of Environmental Protection. Ecol Law Quarterly 27(3). (Summer
2000)
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STAR Graduate Fellowship Conference
U915332
INTEGRATING AGRICULTURAL CENSUSES AND SATELLITE-BASED
CLASSIFICATIONS FOR THE AMAZON AND TOCANTINS BASINS
Jeffrey A. Cardille
University of Wisconsin, Madison
Objectives/Hypotheses: I propose to model the effects of land use practices and land cover change on
terrestrial ecosystems in the Amazon and Tocantins river basins. As part of this research, I expect to focus
on the following four questions: 1) What is the location and intensity of croplands and pastures in the
Amazon and Tocantins basins? 2) How has the location and intensity of croplands and pastures changed on
a decade scale in the past 40 years? 3) How have land transformations affected ecosystem processes,
vegetation structures, and carbon cycling in selected sites within the basins? 4) How might future changes
in land use and/or climate patterns affect carbon storage and nutrient cycling?
Rationale; The Amazon basin, one of the world's great storehouses of carbon, is undergoing significant
change as land use practices replace primary forests with shifting cultivation and pastures. Have changes
in land use—particularly the recent explosive growth in human activity—affected the ecology of the basin
as a whole? Might there be a cumulative effect of converting hundreds of thousands of square kilometers
of forest to shifting cultivation and cattle pastures, and what happens as unproductive sites are abandoned?
By tracking past land use changes, using past patterns to imagine future scenarios of change, and simulating
this in a process-based simulation model, I can add to the ecological and social knowledge being developed
about the basin.
Approach; In this study, I will use IBIS, a model developed at the University of Wisconsin-Madison in the
Climate, People, and Environment Program (CPEP), to answer these and other questions about the impacts
of human land use on the carbon budget of the Amazon basin, IBIS, a dynamic global vegetation model
(DGVM), simulates terrestrial vegetation, soil, and atmosphere processes using detailed information about
land surface physics, canopy gas exchange, plant phenology and physiology, and vegetation dynamics. This
application of IBIS to the Amazon basin will occur as part of the new Large-Scale Biosphere-Atmosphere
Experiment in Amazonia (LBA), a field and modeling collaboration between American and Brazilian
scientists. First, I will assemble a basin-wide historical land use database, using a combination of remote
sensing products (i.e., Landsat and AVHRR data), national inventory data, and other ancillary data. Using
these data, I will construct an empirically-based model of land use activity and land cover conversion in
Amazonia for the last several decades. As part of CPEP's development of a region-specific version of IBIS
for the Amazon basin, I will investigate and model the conversion processes in which farmers and ranchers
create and maintain cultivated fields and pastures in the basin. In conjunction with work to specify plant
types necessary to model the ecology of the basin, I will use land use scenarios as a driver to investigate the
dynamic processes occurring within terrestrial ecosystems that give rise to carbon sources and sinks. Finally,
I will use IBIS, the historical land use database, and scenarios of future land use to evaluate the response of
net carbon exchange to changes within the basin. In particular, we will examine the influences of land use,
climate variability, and increasing CO2 concentration on an extensive suite of IBIS outputs.
Status; The global version of IBIS has been under development for several years and has been tested
successfully on data from many major biomes, including tropical rainforest in Amazonia. We are now in
the early stages of developing the Amazon-specific version of IBIS, have developed the historical land use
database, and are currently integrating this GIS-based knowledge with satellite-based land use/land cover
classifications.
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STAR Graduate Fellowship Conference
Papers & Publications; Cardille, J.A. and Foley, J.A. Integration of agricultural censuses and satellite-
based classifications for estimating cropland and pasture extent in the Amazon and Tocantins basins.
Presentation and abstract in Proceedings, 2000 American Geophysical Union Spring Meeting, May 30,2000,
Washington, DC.
Cardille, J.A., and Foley, J.A. Integrating agricultural censuses and satellite-based classifications for the
Amazon and Tocantins basins. Poster and abstract in Proceedings, 2000 ASPRS Annual Meeting, May 25,
2000, Washington, DC.
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STAR Graduate Fellowship Conference
U915592
EFFECTS OF CLIMATE VARIATION ON SUBALPINE
AND COASTAL VEGETATION AND LANDSCAPES
Charles T. Carlson
University of California, Davis
Objectives/Hypotheses; The goal of this research is to identify climate change impacts versus direct human
impacts on the structure of subalpine and coastal woodlands along the West Coast of the United States. This
study will examine the response of forest elements to global warming and other human dimensions of
environmental change on the California Coast and on the slopes of the volcanic peaks of the Cascade Range.
The highland versus lowland response to climate change will be examined. Lower elevation coastal
woodlands such as those found on the Point Reyes Peninsula, California, and subalpine forests such as those
found on Mount Shasta, California, are selected for study. The purpose of this research is to examine the
stability of the vegetation of subalpine treeline in the Cascade Range and coastal woodland in California at
the elevational extremes of woodland forest as these ecotones may be the first to show response to climate
change.
Rationale; Changing climates may provoke observable vegetation response in these two different woodland
areas at the upper and lower limits of tree growth. Previous work that examines the effects of climate on the
subalpine vegetation of the Cascade Range is sparse in the literature. Perhaps the most well known study
was by Franklin et al. (1971). This study focused on invasion of subalpine meadows by trees on Mount
Rainier, Washington, and Mount Hood, Oregon. It was determined that tree invasions of several subatpine
meadows had occurred during the period from 1928 to 1937. The authors examined a variety of causal
factors for these invasions such as fire suppression, grazing reform and forest edge effect, but concluded that
climatic change was the most probable cause. Taylor (1995) examined forest expansion in relation to climate
change on Mount Lassen, California. He concluded that climatic change influenced mountain hemlock
establishment in the subalpine zone. Although there is a small amount of past research conducted in the
Cascade Range on the topic, past studies conducted on the woodland areas of Point Reyes are lacking in the
literature.
Approach; Mount Shasta is one of the southernmost peaks of the Cascade Range, which is comprised of
a series of island-like volcanoes. The location of study sites and current boundaries of the subalpine treeline
zone were determined through the analysis of large scale aerial photographs and U.S.G.S. 1:24,000 scale
topographic maps. Point quarter methods were used to establish sites for tree sampling. Tree core samples
were taken to assess tree growth response to climate variation. A GIS database will be constructed in order
to perform spatial analysis using ERDAS Imagine. In order to perform analysis of woodland change, tree
cores will be taken and combined with other types of data such as historic aerial photographs.
Status; Thus far, tree core samples have been taken on Mt. Shasta and 1943 aerial photographs of Pt. Reyes
have been ordered from the National Archives. Photographs will then be scanned and registered so that they
may be compared to current aerial photographs to asses the amount of vegetation change. Tree core samples
will be taken from lowland forest at Pt. Reyes.
Paners & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915571
REPRODUCTIVE SUCCESS AND CONSERVATION GENETICS
OF HUMPBACK WHALES IN THE NORTH PACIFIC
Salvatore Cerchio
University of Michigan Museum of Zoology
Objectives/Hypotheses: In this project, genetic markers will be used to assess the distribution of male
reproductive success (RS), estimate the effective population size, and evaluate the genetic structure and
diversity of a relatively small, isolated population of humpback whales that breeds around the Islas
Revillagigedos, off the Pacific Coast of Mexico.
Rationale: Humpback whale populations worldwide were severely depleted by extensive whaling in the
early 20th century, and the species has been protected since 1966. Recent studies have indicated that the
population in the North Pacific is recovering, but at an apparently slow rate. There is much debate regarding
the mating system of the species, though it is generally considered to be polygynous. One of the most critical
pieces of information missing about the breeding biology of the species is a measure of male RS. The degree
of polygyny and mating system in general are a major determinant of the effective population size of a
population and, therefore, have important consequences for conservation genetics and recovery of depleted
populations. Furthermore, this will be the first estimate of male RS distribution in a baleen whale species,
thus having important implications for the study of cetacean breeding systems.
Approach; Small skin samples will be collected from individual whales using a standard biopsy dart that
does no harm to the animal. Different individuals (from a population estimated at 1000) will be biopsied
over the course of four field seasons (1997-2000), including mother-calf pairs and males (candidate fathers).
DNA will be extracted from each sample and all individuals will be genotyped for 8 to 10 microsatellite loci,
providing a unique genetic "fingerprint" similar to that used in forensic analyses. Comparison of mother and
calf genotypes with all candidate male genotypes will reveal putative fathers, from which a distribution of
male RS will be constructed.
Status; During the winters of 1997, 1998, 1999, and 2000, over 800 biopsies were collected off Islas
Socorro and Clarion. This includes over 100 complete mother-calf pairs and approximately 400 different
males. All samples from 1997-1999 have been processed for the extraction of DNA; additionally, all 46
mother-calf pairs from 1997-1999 were genotyped for 4 microsatellite sites in fall 1999. Analysis will
continue in spring/summer 2000, with the extraction of the 2000 samples and microsatellite typing of all
remaining samples. It is estimated that the remaining laboratory work will take approximately 8 to 12
months, to be followed by 6 to 8 months of statistical analysis, writing, and dissertation preparation.
Papers & Publications; Baker, C.S., Calambokidis, J., Medrano, L., Perry, A., Rosenbaum, H., Straley,
J.M., Urban, J., Yamaguchi, M., and von Ziegesar, O. 1998. Population structure of nuclear intron and
mitochondrial DNA variation among humpback whales in the North Pacific. Mol Ecol 7: 695-707.
Cerchio, S. 1998. Estimates of humpback whale abundance off Kauai, 1989-1993: evaluation of biases
associated with sampling the Hawaiian population. Mar Ecol Prog Ser 175:23-34.
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STAR Graduate Fellowship Conference
U915659
EXPOSURE TO ORGANOPHOSPHATE PESTICIDES
IN A MEXICAN AGRICULTURAL COMMUNITY
Guadalupe Chapa
University of California, Los Angeles
Objectives/Hypotheses: Studies that quantify pesticide exposures to agricultural workers and their families
have been conducted in developed countries. Less information is available for similar populations in
developing countries. During the last decade, agricultural production and pesticide use have increased sub-
stantially in larger developing countries such as Mexico. Organophosphate (OP) pesticides such as methyl
parathion and methamidophos are the primary pesticides used throughout Mexico. The main objective of
this study is to quantitatively assess exposure to organophosphate pesticides in farm workers and their
families.
Rationale; It is difficult to distinguish between occupational and environmental exposures for agricultural
communities located in close proximity to fields. Families living in these areas are exposed to pesticides
from residues in soil, groundwater, and harvested crops, as well as exposure from spray drift. Work and
hygiene practices, pesticide use, and storage practices are factors that will affect OP pesticide residue levels
in the home and OP urinary metabolite levels in agricultural workers and their families. A sampling strategy
that integrated the target pesticides, multi-media, and multiple exposure pathways was necessary to-
determine the contribution of environmental and occupational exposures to the total OP pesticide exposures
for pesticide applicators and their families.
Approach; During the 1998 agricultural season, field surveysand observations were conducted to determine
crops harvested, seasonal pesticide use, work practices, and potential exposures to families. Pesticide sales
records indicated that OP pesticide was sold more than any other pesticide class during the last 4 years.
From May 1999 to February 2000, 36 families participated in a multi-media exposure assessment study.
These families participated in three 24-hour sampling periods throughout the season. During each sampling
period, micro-environmental (indoor air, outdoor soil, and house dust), biological (urine), personal dermal
(hand-wipes), and occupational samples (personal air and dermal wipes during an application event) were
collected from pesticide applicat9rs and their families. Target pesticides include methyl parathion,
methamidophos, dimethoate, dichlorvos, diazinon, chlorpyrifos, malathion, parathion, and azinphos methyl.
These samples will be analyzed to: 1) quantify OP residues in the homes of agricultural workers; 2) quantify
OP urinary metabolite (dialkyl phosphates) levels in all participants; and 3) quantify all of these measures
following an application event and determine if these exposures are associated with the levels measured in
family members.
Status; All field sampling was completed in February 2000. Samples are being processed and analyzed.
The expected completion date for the entire study is June 2001.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U91S392
ANALYSIS OF THE IMPACT OF PROTECTED AREA ESTABLISHMENT
ON DEFORESTATION IN CARIBBEAN GUATEMALA
Ted F. Cheeseman
Duke University
O b i ectives/Hy pot heses: The primary objectives of this study were to: 1) develop a baseline dataset of the
current status of natural resources and biodiversity conservation; 2) develop a quantitative and repeatable
basis for understanding land use trends in a research-poor, biodiversity-rich region of a developing tropical
country; and 3) determine the impact of existing conservation legislation on land use preferences and
development trends, to better empower effective conservation action.
Rationale: Fifteen percent of Caribbean Guatemala is under conservation legislation in the form of pro-
tected areas, with another 34% proposed to be protected. Yet, the impact of protected areas on deforestation
and land use is unknown, giving no indication of the potential success of the proposed protected areas.
Approach: To understand the impact of protected area establishment on land conversion rates, I compared
a modeled scenario of expected land use to actual mapped land use, separating the autocorrelation of
protected areas being located only on lands of low economic potential.
Status: I found a narrowly disproportionate area of land expected to be developed but observed to be natural
with in the protected areas, tentatively supporting the hypothesis thatthe protected areas have made an impact
lowering deforestation rates. These conclusions are preliminary and this apparent impact remains small,
amounting to an estimated 5.6% of protected areas maintained under forest cover. This study was successful
in: 1) producing a land use/landcover map for the region of Caribbean Guatemala; 2) establishing a quan-
titative methodology by which the impact of protected areas can be understood; 3) describing development
pattern through four physical environmental variables; and tentatively, 4) measuring the impact of protected
area establishment on deforestation. Use of a time series of land use/landcover maps and more sensitive
modeling will further advance our understanding of what the very young Guatemalan conservation
movement has accomplished and where it should focus.
Research is complete. Manuscript is in preparation (Pat Halpin, co-author) intended for Conservation
Biology.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915586
COST SAVINGS FROM PROPERLY MANAGING ENDANGERED SPECIES HABITATS
Linus Y. Chen
Yale School of Forestry & Environmental Studies
Objectives/Hypotheses: To determine the magnitude of the deferred management debt for endangered
species. Necessary active habitat management for many endangered species has been deferred or neglected,
specifically for imperiled species threatened by invasive exotic species and fire suppression. These results
will be used to show that continued deferred management will lead to more expensive habitat management
and that endangered species recovery will likely fail.
Rationale; Funding for federally listed species has not adequately reflected advances in management and
ecology for the species, in addition to the listing of new species. Adequate funding now will maximize
cost-savings from the recovery of species.
Approach: A survey of management costs for federally listed species threatened by invasive exotic species
and the absence of fire in fire adapted habitats was sent to individuals knowledgeable in habitat management
needs for imperiled species. The survey asked to compare the cost differences between initial "restoration"
control and subsequent maintenance after the threat has been "controlled." The survey also asked to compare
"re-restoration" costs if necessary management is deferred after the threat was "controlled," and the number
of years of deferred management that would lead to a species' extirpation.
A ratio was first determined from the costs of initial restoration compared to minimal maintenance. Second
the cost of continued management was compared to the cost of conducting deferred management for a
project. The accumulated cost of continued management was then subtracted from the cost of deferred
management for the same time period; the time period used was the time when maintenance costs increased
to the deferred maintenance costs. Cost figures were discretely discounted at a 0% and 6% rate.
atus; Work has been completed and was submitted to the journal "Conservation Biology" for review.
Papers & Publications; Chen, L.Y. Cost savings from properly managing endangered species habitats.
Conservation Biol (in review)
Wilcove, D.S. and Chen, L.Y. 1998. Management costs for endangered species. Conservation Biol
12:1405-1407.
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STAR Graduate Fellowship Conference
U915342
EPIPHYTIC MACROINVERTEBRATE ABUNDANCE ALONG A GRADIENT OF EURASIAN
WATER MILFOIL: THE ROLE OF PLANT SPECIES AND ARCHITECTURE
Kendra S. Cheruvelil
Michigan State University
Ob)ectives/Hvpotheses; Many questions have yet to be answered regarding the interactions between
submerged macrophytes, macroinvertebrates, and fish; and how the spread of exotics, such as Eurasian water
milfoil (hereafter milfoil, Myriophyllum spicatum L.\ and our subsequent management actions affect those
interactions. To address some of these questions, I: 1) examined macroinvertebrate abundance on different
submerged plants; 2) determined the sample size and statistical power to detect differences in macro-
invertebrate abundance among species of plants from undissected and dissected plant architecture types; and
3) examined patterns between macroinvertebrate abundance and the percent cover of milfoil.
Rationale; Eurasian water milfoil is an exotic submerged macrophyte found in much of temperate North
America. Because milfoil has three mechanisms of propagation and can grow in water from 1 - 10 m deep,
it has spread rapidly throughout North America. Milfoil forms dense surface mats, or canopies, that suppress
native plant growth and lead to homogeneous macrophyte beds, in addition to interfering with recreational
swimming and boating. Because macrophyte structural complexity is species-specific, certain species
provide more substrate for macroinvertebrates and cover for fish. Although milfoil is a dissected-leaf plant,
and dissected-leaf plants usually have higher macroinvertebrate abundance associated with them, milfoil
supports fewer invertebrates than native plant species. To date, studies have not provided managers with
a clear framework for managing milfoil for the combined purposes of fisheries, recreation, and water quality.
Approach: An ecosystem approach is most relevant to study the inherently complex linkages between
macrophytes, invertebrates, and fish. Therefore, I designed and used a mesh bag sampler that is a modifi-
cation of the folding quadrat sampler to sample macroinvertebrates associated with submerged plants from
six lakes in southern Michigan. Using these data, I assessed the sample size and statistical power to detect
differences in macroinvertebrate abundance among species of plants from undissected and dissected plant
architecture types, examined patterns between macroinvertebrate abundance and the percent cover of mil-
foil, and examined patterns between macroinvertebrate abundance and plant species and architecture. I also
used meta-analysis to quantitatively synthesize the published literature on the relationship between
macroinvertebrates and plant architecture.
Status; I am currently writing up the results of this study and will graduate in August 2000.
Papers & Publications; Cheruvelil, K.S., Soranno, P.A., and Serbin, R.D. Macroinvertebrates associate
with submerged macrophytes: sample size and power to detect effect. Hydrobiologia (submitted, January
2000)
Cheruvelil, K.S., Soranno, P.A., Madsen, J.D., and Roberson, M.J. Epiphytic macroinvertebrate abundance
along a gradient of percent Eurasian water milfoil (Myriophyllum spicatum L) cover: the role of plant
species and architecture. Canadian Journal of Fisheries and Aquatic Sciences (to be submitted in summer
2000).
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STAR Graduate Fellowship Conference
U915204
THE ENVIRONMENTAL FATE OF METHYL TERT BUTYL ETHER
Clinton D. Church
Oregon Graduate Institute
Objectives/Hypotheses: The goal of my research is to characterize the kinetics and mechanisms of in situ
MTBE degradation to provide a better basis for assessment of its impact and potential for natural attenuation
and bioaugmentation.
Rationale: The problems posed by MTBE as a point-source contaminant associated with gasoline spills and
leaking underground storage tanks (LUST) has been recognized for some time. However, recent evidence
suggests that MTBE has also become widespread as a nonpoint-source contaminant in shallow ground water
in some urban areas, and that this contamination may be due to precipitation scavenging and subsequent
infiltration of contaminated rain. These developments, in part, have spurred a reevaluation of the possible
human health impacts, and highlighted the need for a better understanding of processes that control the
environmental fate of MTBE.
Approach; Ethers, in general, are a class of compounds that are characteristically unreactive over a wide range
of industrial and laboratory conditions. It is unlikely, then, that MTBE will be rapidly transformed under
environmentally relevant conditions, and this is consistent with the few data that are currently available. There
are, however, a number of pathways by which degradation of MTBE may occur under atmospheric, in situ, or
remediation conditions. The major possibilities include hydrolysis, enzymatic oxidation, and reaction with
hydroxyl radical. To assess these possibilities, I have focused on the following five objectives: 1) identify
possible degradation pathways and develop analytical methods capable of monitoring the resulting products;
2) assess the kinetics and mechanisms of degradation pathways that lead to rapid removal of MTBE and its
degradation products from the environment; 3) assess the occurrence and kinetics of MTBE degradation under
a variety of ground water conditions; 4) conduct the first detailed assessment of the pathways and kinetics of
MTBE degradation under controlled laboratory conditions simulating those of ground water; and 5) evaluate
the potential for in situ MTBE degradation by biotic or abiotic means under both natural and enhanced
environmental conditions.
Status; Objective 1 is complete, and two manuscripts documenting this progress have been published. As for
Objective 2, a number of researchers have identified tert-butyl formate (TBF) as the likely major atmospheric
degradation product of MTBE and as an intermediate in biotic degradation pathways. I have found TBF to be
labile to hydrolysis, yielding tert-butyl alcohol (TB A). A manuscript documenting the kinetics and mechanism
of this transformation is also published. To complete Objective 3, we have collaborated with various
researchers to assess MTBE occurrence and the products of its degradation. Six manuscripts have been
published that document this work. Experiments to complete Objective 4 comprise kinetics investigations
performed on columns in the laboratory, which are operated under controlled environmental conditions.
Kinetic experiments suggest a half-life of MTBE in the subsurface environment of 2 to 3 years. Two
publications to date document this progress, with one more publication planned once microbial
characterizations of the columns are complete. Completion of Objective 5 will utilize the information gained
in Objectives 2,3, and 4 to assess MTBE degradation under natural conditions. Work is underway to evaluate
MTBE degradation under various enhanced environmental conditions. One of those studies, a bioaugmentation
study, is complete. One publication to date documents this progress, and one more in collaboration with a
former EPA STAR Fellow, Rula Deeb, is in preparation. No course corrections are planned and I expect all
work to be finished by the fall of 2000.
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STAR Graduate Fellowship Conference
Papers <& Publications: Church, C.D. and Tratnyek, P.O. Process level investigations of the in situ
degradation of MTBE. Proceedings of the Joint U.S. Environmental Protection Agency and American
Petroleum Institute MTBE Biodegradation Workshop, Cincinnati, OH, February 1-3, 2000. (in press)
Church, C.D., Pankow, J.F., and Tratnyek, P.G. Effects of environmental conditions on MTBE degradation
in model column aquifers: II Kinetics. 219th ACS National Meeting, San Francisco, CA, Division of
Environmental Chemistry, American Chemical Society, 40(1):238-40.
Church, C.D,, Tratnyek, P.O., and Scow, K.M. Pathways for the degradation of MTBE and other fuel
oxygenates by isolate PM-1. 219th ACS National Meeting, San Francisco, CA, Division of Environmental
Chemistry, American Chemical Society, 40(!):261-63.
Church, C.D., Pankow, J.F., and Tratnyek, P.G. 1999. Hydrolysis of tert-butyl formate: kinetics, products,
and implications for the environmental impact of MTBE. Environ Toxicol Chem 18(12):2789-96.
Church, C.D., Tratnyek, P.O., Pankow, J.F., Landmeyer, J.E., Baehr, A.L., Thomas, M.A., and Schirmer, M.
Effects of environmental conditions on MTBE degradation in model column aquifers. U.S. Geological Survey
Toxic Substances Hydrology Program, Proceedings of the Technical Meeting, Charleston, SC, 1999; 3:93-101.
Schirmer, M., Butler, B.J., Barker, J.F., Church, C.D., and Schirmer, K. 1999. Evaluation of biodegradation
and dispersion as natural attenuation processes of MTBE and benzene at the borden field site. Physics and
Chemistry of the Earth, European Geophysical Society, 24(6):557-60.
Landmeyer, J.E., Chapelle, F.H, Bradley, P.M, Pankow, J.F., Church, C.D, and Tratnyek, P.G. 1998. Fate of
MTBE relative to benzene in a gasoline-contaminated aquifer (1993-98). Ground Water Monitoring &
Remediation 18:93-102.
Barker, J.F., Schirmer, M., Butler, B.J., and Church, C.D. Fate and transport of MTBE in groundwater—
results of a controlled field experiment in light of other experience. In: Proceedings of the Southwest Focused
Ground Water Conference—Discussing the Issue of MTBE and Perchlorate in Ground Water, Anaheim, CA,
June 3-4, 1998, National Ground Water Association, 1998:10-14.
Schirmer, M., Barker, J.F., Butler, B.J., Church, C.D., and Schirmer, K. Natural attenuation of MTBE at the
borden field site. Wickramanayake, G.B. and Hinchee, R.E., eds. In: Natural Attenuation: Proceedings of
the First International Conference on Remediation of Chlorinated and Recalcitrant Compounds, Monterey, CA,
May 18-21, Columbus: Battelle Press, 1998; Cl-3(5):327-321.
Church, C.D., Isabelle, L.M., Pankow, J.F., Rose, D.L., and Tratnyek, P.G. 1997. Method for determination
of methyl tert-butyl ether and its degradation products in water. Environ Sci Technol 3 l(I2):3723-26.
Church, C.D., Isabelle, L.M., Pankow, J.F., Rose, D.L., and Tratnyek, P.G. 1997. Assessing the in situ
degradation of methyl tert-butyl ether (MTBE) with a direct aqueous injection technique for products at the
sub-ppb level. 213th ACS National Meeting, San Francisco, CA, Division of Environmental Chemistry Amer
Chem Soc37(l):411-13.
Buxton, H.T., Landmeyer, I.E., Baehr, A.L., Church, C.D., and Tratnyek, P.G. 1997. Interdisciplinary
investigation of subsurface contaminant transport and fate at point-source releases of gasoline containing
MTBE. In: Anita Stanley, ed. NWWA/API Petroleum Hydrocarbon Conference—Prevention, Detection, and
Restoration, Houston, TX, November 12-14, National Water Well Association and American Petroleum
Institute, pp. 2-18.
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STAR Graduate Fellowship Conference
Schirmer, M, Barker, J.F., Hubbard, C.E., Church, C.D., Pankow, J.F., and Tratnyek, P.O. 1997. The borden
field experiment—where has the MTBE gone? American Chemical Society symposium on the environmental
fate and effects of gasoline oxygenates. 213th National Meeting, San Francisco, CA, Division of
Environmental Chemistry, Amer Chem Soc 37(1):415-17.
Landmeyer, J.E., Pankow, J.F., and Church, C.D. 1997. Occurrence of MTBE and tert-butyl alcohol in a
gasoline-contaminated aquifer. 213th American Chemical Society National Meeting, San Francisco, CA,
Division of Environmental Chemistry, Amer Chem Soc 37(1):413-15.
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STAR Graduate Fellowship Conference
U915636
HIGH ISLANDS AND LOW: THE BIOGEOGRAPHY OF FIJIAN CORAL HEALTH
Tegan P. Churcher
University of California, Berkeley
Ob j cctives/Hvpothcses: Little is known about the cause of coral reef diseases throughout the world. This
research will investigate for the first time the geography of coral diseases in Fiji and examine the emergence
and spread of coral reef disease in the recent past with human and natural impacts by way of mapping the
distribution and pattern of coral disease outbreaks and creating a GIS database. My general research
question examines the distribution of coral diseases and coral reef health in Fiji and what does the history
and geography of that distribution imply about the disease origin, ecology, and transmission?
Rationale: Coral diseases affecting the reef impair a human and biological system that is interdependent
upon this ecosystem. Therefore, conservation and successful management of these resources is of utmost
important to small island nations in the South Pacific with coral reefs. The emergence and spread of these
new diseases have a specific geography and spatial ecology that needs to be investigated. Geographical
analysis of coral reef health will help to unravel the causes of these epidemics and will provide an important
starting point for research on the relationships between environment and ecosystem health, as well as
formulating conservation and responsible management of reef resources.
Approach; Three sets of islands have been chosen as study sites: 1) Ovulua, Vatutheke, Wakaya: The
focus of this group of islands will be to determine how does a fish cannery using hydrocarbons and
ammoniums affect the coral reef as a function of distance? 2) Vatulele and Beqa: The question for these
two islands will be how does an effluent on a large island, Viti Levu, affect a coral reef? 3) Malolo and
Malololailai: The final set of islands will examine the question how does sewage/septic system affect reef?
Each island has a unique geography and environmental history of the reef. By choosing islands with and
without certain variables this research will be able to examine the spatial variability and the changes taking
place in the coral reef ecosystem composition and health. Three methods will be used to obtain these data
on coral reef health at varying spatial scales: 1) local knowledge—we will obtain data from local people who
have first-hand knowledge of the reef to examine the local history of the environment and identify impacts
on the marine habitat; 2) transects and site analysis—we will gather data by doing site-specific ecological
and epizootiology data collection and water quality analysis; and 3) mapping—we will be mapping large-
scale geographic patterns.
Status: My research will continue with field seasons during the summer of 2000 and the winter of 2001.
I plan to file my dissertation in May 2002.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915405
GENETIC CONSEQUENCES OF FRAGMENTATION IN FRASER FIR POPULATIONS
Catherine M. Clark
North Carolina State University
Objectives/Hypotheses: In this study, we are investigating genome distribution and the relationship of
genetic variation and inbreeding to degree of connectivity and population size in Fraser fir (Abies fraseri
(Pursh) Poir.). Specifically, we will address the questions: Is there evidence for altered chloroplast,
mitochondria! and nuclear genome dispersion in stands of different sizes and connectivity? Is the spatial
pattern of relatedness within stands altered by population size and dispersal between stands?
Rationale; Fragmentation of forest habitats has increased dramatically in the last three decades and there
are currently over 7300 tree species considered globally threatened with decline or extinction (IUCN 1998).
Habitat alteration and decreased density of individual trees could diminish dispersal of seeds and pollen in
isolated populations. Small populations are subject to extinction through profound effects of genetic drift,
inbreeding and stochastic environmental events. The role and extent of gene flow that connects small
populations into larger, more viable populations is a critical but poorly understood issue. Furthermore, the
role of inbreeding depression in accelerating demographic processes leading to reduced population viability
remains unclear. The study of genome dispersion in these populations could provide estimates of threshold
levels of size and connectivity required for continued population viability. Recently developed DNA
sequence based markers show utility in examining intraspecific variation in the three genomes of conifer
populations. Uniparental inheritance of chloroplasts and mitochondria in conifers reveals differential rates
of reproduction by individuals, and spatial and temporal variation in dispersion of seeds and pollen.
Approach; Fraser fir, a dominant or subdominant canopy species in high elevation spruce-fir ecosystems,
is threatened with extinction by an introduced insect pest (balsam woolly adelgid). Populations are currently
found on 17 peaks in the southern Appalachians, isolated by distance and elevation. These trees could
demonstrate a metapopulation structure valuable for examining historical and current patterns of gene flow.
Field sampling of Fraser fir will take place in several populations found in Great Smoky Mountains National
Park this year. DNA will be extracted from these samples and genome variability characterized with
paternally inherited chloroplast microsatellite loci, maternally inherited mitochondria! markers and bi-
parentally inherited nuclear loci.
Status; Preliminary molecular assessment on population samples collected in Great Smoky Mountains
National Park during the 1999 field season has been initiated. Nuclear microsatellite markers are currently
being developed.
Papers & Publications; Clark, C.M., Wentworth, T.R., and O'Malley, D.M. 2000. Genetic discontinuity
in eastern North American Abies (Pinaceae). Amer J Botany (in press)
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STAR Graduate Fellowship Conference
U915665
FRUGIVORE IMPACT ON SEED RAIN PATTERNS
IN A CENTRAL AFRICAN TROPICAL FOREST
Connie J. Clark
San Francisco State University
Objectives/Hypotheses: This study investigates the relative significance of dispersers on the initial phase
of forest organization, the seed rain. We ask the following questions: To what degree do arboreal frugivores
influence the species richness and abundance of the seed rain? Do arboreal frugivores differentially disperse
the seeds of specific life forms? Do unrelated taxa (frugivorous birds, monkeys, and rodents) represent
similar or distinct functional dispersal groups?
Rationale; Because few tropical plant species have been found to produce seeds with long dormancy
mechanisms, forest regeneration results from recent input of seeds from the seed rain. Most tropical plants
produce fleshy fruits, and vertebrate frugivores act as their primary dispersal vectors. However, behavioral
disparities among dispersal vectors could influence patterns of seed distribution and thus, forest structure.
Approach; Seed rain was sampled for 12 months in the Dja Reserve, Cameroon. Traps were erected below
the canopies of 90 individuals from nine focal tree species; three dispersed by monkeys, three dispersed by
large birds, and three dispersed by wind. All seeds, fruits, and fruit or seed pieces were collected from traps
at 10-day intervals.
Status; The above abstract represents one facet of this project. I am currently examining: 1) to what degree
fruiting trees act as dispersal foci in closed canopy forests; 2) differential seed shadows generated by avian
and primate frugivores for six focal tree species; 3) if seed rain patterns produced by the frugivore
community result in predictable associations among tree species in the adult forest structure.
Papers & Publications; Clark, C. J., Poulsen, J.P., and Parker, V.T. Frugivore impact on seed rain patterns
in a central African tropical rain forest, (in review)
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STAR Graduate Fellowship Conference
U915199
GENETIC ALGORITHMS FOR MODEL DEVELOPMENT AND PROCESS DESIGN
IN ENVIRONMENTALLY-CONSCIOUS DESIGN AND MANUFACTURING
John M. Clayton
Georgia Institute of Technology
Objectives/Hypotheses: The goal of the project is to develop a general approach to finding design solutions
with good predicted environmental performance for chemical industrial processes. The project will focus
on developing Genetic Algorithm (GA)-based approaches for parameterizing mass-balance-based models
and on applying GA-based systems to these models in decision-making under ECDM goals. These
approaches will have the ability to identify multiple attractive regions of parameter and design space if they
exist. The GA-based systems will be applied to the development of a new C12/C102 pulp bleaching model
and to the use of this model to identify environmentally friendly bleaching conditions with minimum cost
and satisfactory product quality.
Rationale: When makingdesign decisions within ECDM efforts, one must often incorporate mathematically
complex environmental models in optimization procedures. The models are usually nonlinear and often have
no closed analytical form, requiring one to use numerical approaches to determine solutions and making
gradient information impossible to obtain. These models may also reflect real-world situations where there
are more than one set of conditions that are attractive to the designer. Because of these complexities, most
traditional optimization procedures cannot be applied to these models. Genetic Algorithms (G As) are newer
optimization procedures that have been successfully used in solving design problems that rely on complex
models, including those problems that contain multiple local optima.
Approach; A new chemical-kinetic model for (CD)E bleaching will be developed based on existing
literature data and existing general knowledge of bleaching reactions. Kinetic parameters will be fit using
a GA set to minimize the discrepancy between data and predictions. GA constraints will be applied which
embody current knowledge about relative reaction rates. The results of the GA parameter fitting will be fed
to a clustering algorithm (CA), identifying distinct groups of "similar" parameter sets. These groups should
correspond to distinct regions of parameter space yielding relatively low predictive error. One para-
meterization will then be selected (criteria to be determined) and the model will be applied in different
optimization problems (e.g., minimize cost, constrain AOX emissions and lignin removal; constrain cost,
AOX, and lignin removal and identify satisfactory design regions based on these criteria). Optimization will
be performed using the same GA/CA system as before.
Status; The GA and CA have been developed. Visualization tools for output from the GA/CA and the mo-
del itself are under development and nearing completion. The conceptual structure of the model has been
outlined and the model and solution mechanism have been implemented. Parameter fitting for the C12-only
reaction subset is under way.
Papers & Publications; Genetic Algorithms in Environmentally-Conscious Design and Manufacturing.
Poster presentation. 1999 Georgia Tech Environmental Engineering Graduate Research Symposium, Bill
Moore Student Success Center, Georgia Institute of Technology, May 6,1999.
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STAR Graduate Fellowship Conference
U915533
DEVELOPMENT OF A BIOINDICATOR OF FRESHWATER INFLUX TO MARINE
COMMUNITIES USING A SALINITY-SENSITIVE SYMBIOSIS IN THE TEMPERATE
SEA ANEMONE ANTHOPLEURA ELEGANTISSIMA
Risa A. Cohen
University of California, Los Angeles
Objectives/Hypotheses: To investigate the potential for using the symbiotic sea anemone, Anthopleura
elegantissima, as an indicator of salinity stress. The specific purpose of these studies is to begin to understand
how changes in environmental conditions affect the relationship between A. elegantissima and its symbiotic
zooxanthellae, with the ultimate goal being to develop a bioindicator to measure freshwater influx into coastal
subtidal marine communities.
Rationale: The importance of abiotic factors in shaping species distributions and community structure is well
known. For example, distinct invertebrate communities have been found to be associated with high or low
salinities (Mees, 1993; Metzeling, 1993; Gaughan and Potter, 1995), and short term salinity stress affects
species composition and abundance (Nacorda and Yap, 1997). Hyposaline conditions are of particular concern
in southern California. The climate in this region consists of distinct wet and dry seasons, and the majority of
the rainfall is limited to the winter months (November-March). Southern California is also highly populated,
and there are a number of wastewater treatment plants releasing hyposaline effluent to the ocean. This results
in year-round freshwater input to a system that normally experiences distinct wet and dry periods (e.g., Zedler
et al. 1992; Dalkey and Shisko, 1993; Johnson, 1993). Organisms with symbioses, such as anemones and
corals, may be especially sensitive to changes in abiotic factors (Engebretson and Martin, 1994; Brown, 1997).
Thus, symbiotic marine invertebrates with quantifiable responses to stress have potential for use as indicators
of changing environmental conditions.
Approach: I am using three approaches in the development of a temperate bioassay for salinity. 1) A number
of short-term laboratory experiments to examine the response of A. elegantissima to a range of decreased
salinities under various environmental conditions. These experiments are designed to examine the effect of
freshwater alone (chronic or pulsed) on A. elegantissima as well as to uncouple the effect of other factors
(temperature, light intensity, nutrient concentrations) that interact with salinity in the field. 2) In situ
microcosm experiments to test whether the bleaching response in the lab is similar to that in the field.
Anemones will be exposed to known salinities, but subjected to more natural conditions (e.g., light and
temperature). The experimental design will consist of anemones attached to plates with rock-like texture,
enclosed in a clear plastic structure, weighted and attached to the substrate. Water of a known salinity can then
be poured into the structure prior to deployment of the experiment, or if the units are filled in the field, a known
volume of freshwater can be injected into the experimental unit in situ. 3) Finally, to test the usefulness of
Anthopleura elegantissima as a bioindicator of freshwater influence in the field, individuals will be positioned
in a range of sites with known amounts of freshwater input as well as sites that receive very little. For all
experiments, the response variables are the number of symbiotic zooxanthellae remaining per mg of animal
protein and chlorophyll content.
Status: During the first year of research, I evaluated different methods for quantifying zooxanthellae, and
began performing laboratory experiments to establish the effects of salinity, light, temperature and nutrients
on the number of symbiotic zooxanthellae lost from A. elegantissima.
Papers & Publications: Cohen, R.A. and Pechenik, J.A. 1999. Relationship between sediment organic
content, metamorphosis, and postlarval performance in the deposit-feeding polychaete, Capitella sp. I. J Exp
MarBiolEcol 240(1):1-18.
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STAR Graduate Fellowship Conference
U915156
EFFECTS OF FIRE FREQUENCY AND RED IMPORTED FIRE ANTS
ON NATIVE INSECTS IN A LOUISIANA LONGLEAF PINE SAVANNA
Deanna M. Colby
Louisiana State University
Objectives/Hypotheses; Protocols for restoring and maintaining endangered ecosystems have been
established from historical perspectives, but it is equally important to modify regimes in response to unique
circumstances resulting from modern day events, such as the introduction of exotic species. The objective
of this research was to determine an appropriate burning regime based on native insect population responses
to different fire frequencies. This regime would minimize establishment of the red imported fire ant while
maintaining indigenous plant and animal communities.
Rationale: Two percent of the original longleaf pine ecosystem remains in fragmented patches throughout
its historical range. Prescribed burns are employed to restore diversity of native, fire-adapted inhabitants.
Exotic species often complicate and/or hinder efforts to maintain native diversity. For example, Solenopis
invicta, the red imported fire ant, has invaded virtually every habitat in the southeastern United States since
its introduction in the early 1930s. These ants have been shown to decrease native insect species by 70
percent. Unfortunately, not much is known about species-specific responses to various burning regimes or
the deleterious impact imposed by exotic species in those regimes. Little information exists with which to
base educated decisions for the effects restoration efforts have on biodiversity of arthropods. This research
will benefit conservation organizations interested in longleaf pine ecosystem preservation by: 1) providing
a species list from which to monitor long-term changes in insect diversity; 2) supplementing current
information about effects of fire on diversity of insects; and 3) producing data on the impact of red imported
fire ants on insect diversity under current burning regimes.
Approach; We chose to focus our attention on Solenopsis invicta and native ants and beetles. Species of
interest are ground dwelling insects persistent in the habitat and most likely in direct competition with S.
invicta for resources. The research site was a longleaf pine savanna that had not been burned in 8 years. We
established 12 one-hectare circular plots with 12 pitfall traps and one flight intercept trap per plot. Each plot
received one of four treatments: annual burning, annual burning with Amdro, biennial burning, and biennial
burning with Amdro. Amdro was applied as a formicidal bait directly to S. invicta mounds. Prescribed
burns were applied in August 1997 and 1998. Sampling was conducted from August 1996 through August
1999. Species were collected twice per month for 48 hours each time. Environmental variables such as leaf
litter dry weight, grass height, soil moisture, and soil temperature were recorded for each plot.
Status: Sampling has been completed. Native ant species have been processed and identified. Identification
of beetle species is ongoing.
Papers & Publications: None at this time.
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STAR Graduate Fellowship Conference
U915627
BIOGEOGRAPHICAL COMPARISON OF NUTRITIONAL EFFECTS OF THE TOXIC
DINOFLAGELLATE ALEXANDRIUM SP. ON THE COPEPOD ACARTIA HUDSONICA
Sean P. Colin
University of Connecticut
Objectives/Hypotheses: The general goal of this study is to examine the copepod-toxic dinoflagellate
interaction in the framework of the latitudinal (and toxicity) gradient represented by the spreading of
Alexandrium. We hypothesize that there may be geographical differences in the effects of local strains of
Alexandrium on physiological, population and behavioral biology of individuals of local strains of dominant
copepod species. We then will address the following questions: 1) Are the observed geographical differ-
ences in the biological processes of the copepods due to toxicity variations in the dinoflagellate strains, to
differences among the populations within the copepod species, orto the interaction of the dinoflagellates and
copepod strains? 2) If differences are due to the copepods, are they due to genetic adaptation or physio-
logical acclimation?
Rationale; The frequency and duration of harmful algal blooms (HABs) have been increasing worldwide,
with profound ecological and economical consequences. Along the east coast ofNorth America the complex
of Alexandrium fundyense and A. tamarense appears to have spread in its geographical distribution. The
spreading, which has occurred perhaps for over a century, has been from the north (Canada) to the south
(New Jersey), with the northernmost waters having more frequent and toxic blooms than the southernmost
waters. Because of the longer time to which grazer populations in the northern waters have been exposed
to Alexandrium, one may hypothesize that these populations have developed adaptations to better deal with
this toxic alga. However, the consequences to grazers, and hence the fate of toxins in the food web, of the
spreading of these toxic dinoflagellates are not well known or understood.
Approach: To test the hypothesis, we will employ strains of Alexandrium and copepods collected from
locations in Canada, Maine, Massachusetts, and Connecticut and eopepods collected additionally from
southern New Jersey (location where Alexandrium blooms have not occurred). Copepods from the different
sites will be exposed to dinoflagellates from one site, and vice versa. In all the copepod-dinoflagellate
combinations, rates of copepod cell ingestion, egg production, egg hatching, individual survival and behavior
will be measured and differences among combinations statistically analyzed. Physiological acclimation by
copepods will be examined by comparing copepod rate processes through length of time of exposure to the
dinoflagellates. The ability of copepods to adapt to an exposure to toxic Alexandrium will be analyzed using
laboratory selection experiments.
Status; Experiments are underway and preliminary results have revealed a significant difference in the
copepod-harmful dinoflagellate relationship at different regions along the northeast coast ofNorth America.
Papers & Publications: Colin, S.P. and Dam, H.G. 2000. Biogeographical comparison of nutritional
effects of the toxic dinoflagellate Alexandrium sp. on the copepod Acartia hudsonica. Abstract. ASLO
Copenhagen 2000 Meeting.
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U915456
CRITICAL BODY RESIDUES AND ION-EXCHANGE MEMBRANES AS MEASURES
OF HEAVY METAL BIO AVAILABILITY AND TOXICITY IN SOIL
Jason M. Conder
Oklahoma State University
Objectives/Hypotheses: To better understand the bioavailability and toxicity of cadmium (Cd), lead (Pb),
and zinc (Zn) to soil organisms, both as individual contaminants and as a mixture.
Rationale: To adequately protect or restore soil ecosystems, there is a great need to characterize soils
suspected or presumed to be contaminated with heavy metals. Traditional chemical exposure analyses of
soils, which determine total heavy metal concentrations, are often not well correlated with soil organism
toxicity due to a host of modifying factors such as pH, organic matter content, and clay content. Due to these
modifying factors, no soil will have 100% of its metal content bioavailable to organisms. Only bioavailable
metals in soil are able to exert toxic action. Bioavailable metals cannot be directly measured using chemical
analyses—only living organisms determine bioavailability. Laboratory toxicity tests, in which soil organ-
isms are exposed to contaminated soils, are routinely used to evaluate toxicity and/or contaminant
bioavailability, but are time consuming, expensive, and often difficult to interpret. A more useful method
of evaluating soils would be a surrogate measure of metal bioavailability that would not only be inexpensive
and precise, but also relate directly to toxicity.
Approach: Two methods of measuring metal bioavailability in soils were investigated: 1) earthworm metal
residues, and 2) ion-exchange membrane uptake. Single- and multiple-metal toxicity tests using the
earthworm Eisenia fetida and ion-exchange membrane exposures were conducted in artificial soil spiked
with metal salts. Toxic units were calculated from the single-metal tests in order to evaluate mixture toxicity
of the multiple-metal test. During all toxicity tests, dead earthworms were analyzed to determine critical
body residues (CBRs) for lethality for each metal. CBRs are concentrations of toxicants in an organism
associated with a toxic endpoint, providing a link between the measure of bioavailability (the residue) and
toxicity. CBRs were also used to further investigate mixture toxicity. Plant Root Simulators™ (PRS™,
Western Ag Innovations, Saskatoon, SK, Canada), ion-exchange membranes coated with a heavy metal
chelating agent, were exposed to artificial soils at the same concentrations as the earthworm toxicity tests.
PRS uptake was compared to toxicity (mortality) and CBRs to investigate their suitability as surrogates for
earthworm bioassays.
Status; All four toxicity tests (Cd, Pb, Zn, and multiple-metal mixture), earthworm residue analysis, and
PRS exposures have been completed. Toxicity data indicate that mixture effects of Cd, Pb, and Zn are
additive (summing the molar concentrations of the individual metals predicted toxic effects). CBRs have
been developed for Cd, Pb, and Zn, and have proven to be useful links between toxicity and exposure/
bioavailability. PRSs are useful as screening tools for available metals in soil, but are not well related to
earthworm toxicity or metal uptake.
Papers
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STAR Graduate Fellowship Conference
U915578
INVESTIGATING BLUE WHALE (BALAENOPTERA MUSCULUS) POPULATION
STRUCTURE USING INTRONS OF CONSERVED NUCLEAR GENES
Carole A. Conway
University of California, Davis
Objectives/Hypotheses: The main goal of this project is to investigate whether there are separate stocks
(populations that are essentially demographically independent) of blue whales (Balaenoptera musculus) in
order to designate meaningful management units for conservation. If separate stocks exist, the phylogenetic
relationships among them will be examined to assess the level of diversity within the species. This work will
be conducted using molecular genetic markers, introns of conserved nuclear genes. An ancillary objective
is to evaluate the usefulness of nuclear introns in comparison to other markers for answering questions at
the population, subspecies, and species levels.
Rationale: Although it is listed as an endangered species, very little is known about the status of the blue
whale. In order to perform a viability assessment, it is critical to have an understanding of the population
structure of the species. The recovery plan for the blue whale recommends that genetic analyses be
conducted in conjunction with telemetry studies to elucidate stock structure. In addition, the exploration of
the usefulness of nuclear introns may significantly contribute to the conservation of other species by
providing information on additional nuclear markers for genetic research.
Approach; Skin samples or DNA template for genetic analyses will be obtained from the collections of
governmental agencies, private organizations, and other academic institutions worldwide. I will examine
the variation present in at least 10 introns using the polymerase chain reaction (PCR), single-stranded
conformational polymorphisms (SSCP), and direct sequencing. The experimental design consists of two
phases. In the first phase, I will test the PCR amplification of approximately 80 different introns using
published primers. Those introns that can be successfully amplified will be screened for variation using
SSCP. Five to ten individuals from distant regional populations (chosen to represent the entire geographic
range) will be used for the screening. Those introns that appear to contain the most potentially informative
variation will be carried into the next phase. In the second phase, at least 10 introns will be amplified in all
samples and the PCR products resolved on an SSCP gel. SSCP also serves to purify alleles of heterozygotes
for subsequent sequencing. All allele variants will be excised from the gel, reamplified and sequenced using
an automated system. The data will be analyzed using population genetic statistical methods and a
phylogeographic approach. F statistics will be calculated for each locus and for all loci combined. DNA
sequence data will be analyzed phylogenetically using parsimony and maximum likelihood algorithms. The
resulting gene trees will be compared to the biogeography of the species to look for any associations that
may indicate separate stocks and the evolutionary relationships among them. The usefulness of introns as
markers for answering intraspecificand interspecific questions will be evaluated using the results from this
study as well as results published by other researchers. I will evaluate introns based on three criteria: level
of variation, level of homoplasy, and accessibility for use on a broad range of taxa.
Status; I am in the first phase of the project, which involves screening introns for the most potentially
informative variation. Preliminary results have indicated that the level of variation within introns of blue
whales is relatively high. Of 10 loci screened, 7 are polymorphic; the number of alleles per locus ranges
from 2-6. 1 anticipate completing this project by September 2002.
Papers & Publications: None at this time.
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U915568
PARTITIONING OF ETHOXYLATED NONIONIC SURFACTANTS
IN WATER/NON-AQUEOUS PHASE LIQUID (NAPL) SYSTEMS:
EFFECTS OF SURFACTANT AND NAPL PROPERTIES
Matthew A. Cowell
University of Michigan
Objectives/Hypotheses; The goal of this research is to develop an understanding of the effects of surfactant
and non-aqueous phase liquid (NAPL) properties on surfactant partitioning in water/NAPL systems.
Rationale: Surfactant-based remediation has received considerable attention as a potential technology for
enhancing conventional pump-and-treat remediation processes for aquifers contaminated with organic
non-aqueous phase liquids (NAPLs). In surfactant remediation, NAPL contaminants can be removed by
two processes: sol utilization and mobilization. Although these processes have been extensively studied,
limited information is available regarding the partitioning of nonionic surfactants between aqueous and
organic phases. Because surfactants are amphiphilic molecules that have a finite solubil ity in aqueous phases
and NAPL, partitioning between the two phases is expected.
Approach; Batch equilibrium experiments were conducted to examine the effect of surfactant and NAPL
properties on the partitioning of nonionic surfactants between different aqueous and non-aqueous phases.
Ethoxylated nonionic surfactants with different chemical structures and mixture distributions were used
coupled with NAPLs covering a wide range of NAPL/water interfacial tensions.
Status; An in-depth understanding of the effects of surfactant and NAPL properties on surfactant parti-
tioning was gained in this research and a correlation was developed. A paper detailing the results was
published in Environmental Science & Technology.
Papers & Publications; Cowell, M.A., Kibbey, T.C.G,, Zimmerman, J.B., and Hayes, K.F. 2000. Parti-
tioning of ethoxylated nonionic surfactants in water/non-aqueous phase liquid (NAPL) systems: effects of
surfactant and NAPL properties. Environ Sci Technol (in press)
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U915634
A REVIEW OF STEEP CHANNEL DESIGN METHODOLOGIES
Joanna C. Crowe
The Johns Hopkins University
Objectives/Hypotheses; Steep stream design has become one of the most difficult issues facing the
restoration community. Many channels subject to restoration are those that were once moderately sloped
and have eroded to a steep gradient. These channels have high energy flow over an erodible bed and a
channel profile with a large elevation drop over a short distance.
Rationale; The restoration of these channels needs to meet multiple objectives, including a stable channel
morphology, a cessation of erosion from the channel bed, suitable habitat conditions, and the bridging of
discontinuous channel bed elevations.
Approach; Step pool sequences are the most common solution used in the redesign of steep channel
segments. Bedform design specifics are usually constrained by an established channel slope and channel
width. Therefore, step pool designs are based upon the combination of discharge, step forming clast size,
individual step spacing, and pool depth chosen. There are a number of different methodologies in use for
determining these variables, yet there is not one method that has been proven most successful. Recent
literature includes studies focused on the hydraulics of steep streams, resistance of step sequences, and the
rearrangement of natural step-pool sequences during a large flood event. Results from this research provide
some guidance concerning the behavior of step pool bedforms and steep channels. While the goal of many
design channels is not to mimic nature, the information provided by the data gathered in the field coupled
with flume studies of steep channel hydraulics can be useful in the evaluation of different design
methodologies.
Status; This work is currently in progress.
Papers & Publications: None at this time.
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U915310
SUPERFUND IMPLEMENTATION ANALYSIS: EXAMINING THE PROGRAM'S
UNINTENDED CONSEQUENCES AND ENVIRONMENTAL PROGRESS
Dorothy M. Daley
University of California, Davis
Objectives/Hypotheses; The main objective of this research is to understand and quantify the impacts of
Superfund implementation. Specifically, this research examines two different areas of Superfund. First, the
project explores the unintended effects of Superfiind participation on current hazardous waste generation
patterns at the firm level. In other words, do firms that have Superfund "experience" (i.e., firms that have
been named responsible parties at Superfund sites, differ systematically in their waste generation patterns
from non-Superfund firms? The second aspect of this research examines factors that impact environmental
progress at Superfund sites. The objective is to understand why some Superfund sites are more likely to be
remediated than others.
Rationale; The Comprehensive EnvironmentalResponse,Compensation and Liability Act, more commonly
known as Superfund, is designed to remediate the nation's worst hazardous waste sites. It is a reactive
program, responding to the problem of existing waste sites. Yet, many scholars and practitioners believe
that Superfund has had a profound impact on current waste generation. This research is the first attempt to
empirically examine that belief. It will provide quantitative information on the effects of Superfund
participation on current hazardous waste generation. In addition, this research will also analyze factors that
affect site remediation. It will provide empirical insight on the relative importance of scientific,
technological, socio-economic, and demographic factors affecting environmental progress at California
Superfund sites. This information, in turn, can be used by policy makers and practitioners to identify
variables that could facilitate remediation of hazardous waste sites.
Approach; There are two different methodological approaches for this research project. To explore
Superfund's unintended consequences, a database linking Superfund's responsible parties and the Resource
Conservation and Recovery Act's (RCRA) large quantity waste generators was compiled. This database
included all waste generators in the United States that were required to report under RCRA in 1995 and 1997.
Additional secondary data on factors affecting waste generation was added to the database. Regression
analysis was used to model the impact of Superfund participation on RCRA waste generation. The second
part of the research project focuses on California Superfund sites. Site level data will be collected for the
66 non-federal Superfund sites in California. In addition, a mail survey will be administered to organizations
and individuals who are actively involved in Superfund implementation. This will include federal, state, and
local governmental officials, environmental and business organizations, as well as journalists and other
interested parties. The site level and the survey data will be analyzed to determine what factors are
associated with effective environmental progress.
Status; The first part of this research, examining unintended consequences, is complete. The second part,
examining factors associated with environmental progress, is on going.
Papers & Publications; Daley, D. Does Superfund participation impact current waste generation patterns:
a firm level analysis. Paper presented at the Annual Meeting of the Western Political Science Association,
San Jose, CA, March 24-26,2000.
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U915425
DEVELOPMENTAL NEUROTOXICITY OF THE PESTICIDE,
CHLORPYKTFQS: MECHANISMS AND CONSEQUENCES
Kristina Dam
Duke University
Objectives/Hypotheses: Our goal is to examine the adverse neurodevelopmental effects resulting from
neonatal chlorpyrifos exposure. Although large doses of chlorpyrifos are required to produce gross
dysmorphogenesis, it is postulated that developmental neurotoxicity may occur at much lower doses through
the targeting of events specific to development. Macromolecule synthesis associated with neural cell
replication and differentiation is one such event. Unlike many other cells, neural cells undergo mitosis dur-
ing a distinct "window" that irrevocably closes at the end of neurogenesis. Studies from our lab have shown
that a single dose of chlorpyrifos can inhibit DNA synthesis in the developing brain. Likewise, repeated
lower doses cumulate to inhibit DNA synthesis persistently, eventually producing deficits in cell number.
Alterations at the cellular level (DNA synthesis, cell death, etc.) do not necessarily infer behavioral
teratogenesis, rather alterations in specific functions, such as synaptic development and neurotransmission,
are required. However, exposure to chlorpyrifos has been shown to alter the development of cholinergic
synaptogenesis and produce hyperactivity in catecholaminergic neuronal activity as well as elicit changes
in the development of coordination skills and locomotor activity. Considering these results, and the fact that
synaptic organization and consolidation of behavior continues into childhood and adolescence in all species,
the vulnerable period for chlorpyrifos neurotoxicity may need to be extended to encompass the long term
effects of childhood exposure.
Rationale; Chlorpyrifos is a pesticide whose wide applicability and safety compared to parathion has led
to its widespread use. As with other compounds of its class, chlorpyrifos inhibits cholinesterase, resulting
in both acute delayed neuropathy, though the later generally requires doses high enough to elicit lethality.
Nevertheless, recent concern over the use of pesticides, especially the exposure of children and pregnant
women, has led to animal studies of the developmental toxicity of chlorpyrifos.
Approach; For our studies, we use a neonatal rat model since the early postnatal period in rat (postnatal day
1-14) roughly corresponds to the neurodevelopment from the third trimester to the first postnatal year in the
human. The treatment paradigm used involves repeated exposure during two developmental periods, PN1-4
(examined on PN5 or 10) or PN11-14 (examined PN15 or 20). Doses used lie well below the threshold for
systemic toxicity, producing no mortality or weigh deficits.
Status: Dissertation project is complete.
Papers & Publications; Dam, K., Seidler, F.J., and Slotkin, T.A. Chlorpyrifos exposure during a critical
neonatal period elicits gender-selective deficits in the development of coordination skills and locomotor
activity. Developmental Brain Research (in press)
Dam, K., Seidler, F.J., and Slotkin, T.A. 2000. Behavioral deficits after exposure of neonatal rats to the
insecticide, chlorpyrifos. The Toxicologist 54(1):318.
Dam, K., Seidler, F.J., and Slotkin, T.A. 1999. Chlorpyrifos-induced release of norepinephrine from rat
brain synaptosomes. Developmental Brain Research 118:129-133.
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Dam, K., Garcia, S.J., Seidler, F.J., and Slotkin, T.A. 1999. Neonatal chlorpyrifos exposure alters synaptic
development and neuronal activity in cholinergic and catecholaminergic pathways. Developmental Brain
Research 116:9-20.
Dam, K., Crumpton, T.L., Trauth, J.A., Seidler, F.J., and Slotkin, T.A. 1999. Effects of neonatal
chlorpyrifos exposure on nuclear transcription factors involved in CNS cell differentiation. FASEB Journal
13(5):LB128.
Dam, K., Garcia, S.J., Seidler, F.J., and Slotkin, T.A. 1999. Effects of neonatal chlorpyrifos exposure on
the development of neuronal activity. The Toxicologist 48(1-S):1194.
Dam, K., Seidler, F.J., and Slotkin, T.A. 1998. Developmental neurotoxicity of chlorpyrifos: delayed
targeting of DNA synthesis after repeated administration. Developmental Brain Research 108:39-45.
Dam, K., Roy, T.S., Seidler, F.J., Andrews, I.E., and Slotkin, T.A. 1998. Repeated chlorpyrifos decreases
DNA synthesis in neonatal rat brain. The Toxicologist 42(1-S):1294C.
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U915594
SUPPLY CHAIN MANAGEMENT FOR INFRASTRUCTURE DEVELOPMENT
OF SOLAR ENERGY RECHARGING STATIONS
Tarsha N. Dargan
Florida A&M University
Ob j ectives/Hypotheses; The objectives of this research work are to: 1) establish the theoretical foundation
for wide-scale setup of solar powered charging stations for electric vehicles, and 2) efficiently provide the
deliverable to the customer via supply chain management tools and techniques.
Rationale; In today's highly consumptive society, it imperative that an alternative method of energy
generation be fully explored. Not only because of the dwindling supply of fossil fuel and the effect of
external impactors on the cost market, but also and most importantly, the adverse environmental impact
associated with gasoline powered vehicles. The impacts have moved from a local or national nuisance to
a major contributor to global disturbances. Some suggested methods of dealing with this phenomenon are
mast transit, bicycle riding, carpooling, and vehicle sharing.
Today, the stage is set for wide-scale marketing of low impacting vehicles. A crucial step was the challenge
by President Clinton for a highly fuel efficient vehicle. The electric vehicle can even surpass this challenge,
yet its requirements are vastly different from gasoline powered vehicles. The vehicle technology is being
honed, now the question becomes how to set up the streets, charging facilities, etc., to handle these low
impact vehicles.
Approach: Previous work has explored teaming the fossil fuel powered charging facilities with fast food
restaurants to compensate for lengthy charging times or setting up chargers at park-rides and office
complexes. This research presents the use of a totally renewable, non-polluting energy source, solar energy,
for battery recharging, as well as on-site battery exchange to make the wait times more conducive to normal
vehicle "filling" times. A network will be setup to simulate optimal station location based upon the number
of customers to be served, minimal wait times, efficient provision of the service to the customer, etc. One
of the success factors in the implementation is making sure that the batteries are in the proper position at the
proper time. Supply chain management will be used to ensure that these needs are met timely and cost
effectively. The supply chain is the group of manufacturers, suppliers, distributors, and retailers working
in concert to supply goods and services to its local, national or international customers. By optimizing the
supply chain, managers have experienced quicker response to market demands, lower risk, and higher
quality.
Status; I am currently in the initial stages of the research working on the literature survey. My expected
doctoral completion date is July 2002.
Papers & Publications; Owusu, Y.A., Dargan, T., Richardson, K.M., and Thagard, J. Systems approach
to incorporate design into environmentally conscious design and manufacturing course. 2000 ASEE
Conference, (in press)
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U915615
COLLECTIVE ENVIRONMENTAL ACTION FROM AN ANTHROPOLOGICAL
PERSPECTIVE: A STUDY OF ENVIRONMENTAL MOVEMENTS IN THE UNITED STATES
Vinci E. Daro
University of North Carolina, Chapel Hill
Objectives/Hypotheses: My objective is to bring anthropological knowledge to bear on the social and
cultural aspects of environmental degradation. I would like to help develop, and participate in, avenues for
new forms of collaboration between social scientists, ecologists, and policy-makers in developing strategies
for responding to environmental concerns that are culturally relevant to local communities in the United
States and around the world.
Rationale; Public desires to respond to environmental problems are channeled in different directions
depending on the highly diverse cultural contexts within which people make sense of the world and their
place in it My research focuses on the relationships between cultural meaning, individual experience, and
social action as they emerge through participation in environmental movements. In particular, I analyze the
connections between public debates about the most appropriate response to environmental problems and the
personal experiences of those who are engaged in collective environmental action at the local level.
Approach: Using research tools and theoretical approaches developed by anthropologists, my work draws
ethnographic material from local environmental struggles, and broader contextual material from political
debates taking place nationally. Participant observation, open-ended personal life-history interviews, and
reviews of media coverage of environmental issues are my primary research tools. My theoretical approach
includes 'social practice theory,' which focuses on the way identities and commitments develop in social
practice, and 'political ecology,' which focuses on conflicting cultural values that shape—and are shaped
by—environmental struggles.
Status: I have reviewed a great deal of participant observation and interview material generated by a 4-year
ethnographic study, funded by the National Science Foundation, of local environmental groups in North
Carolina and Delaware. I have also analyzed a wide range of ongoing public debates about environmental
problems taking place in national and local print media, television and radio programs, and industry
publications. I have just completed a major paper equivalent to a Master's Thesis based on this work, and
I am now beginning work on a book chapter and conference paper on related topics.
Papers & Publications; Daro, V.E. 2000. Public contest, personal struggle: constructing appropriate
environmental action in a neoliberal world. Fourth Semester Paper, UNC, Chapel Hill.
Daro, V.E. 2000. Dealing with incommensurability: materialist perspectives on economy and ecology.
Course paper for Politics of Nature, Professor Arturo Escobar, UNC, Chapel Hill.
Daro, V.E. 2000. Contextual factors of the emergence of environmental movements. Course paper for
Identity and Agency, Professor Dorothy Holland, UNC, Chapel Hill.
Daro, V.E. 1999. From radicals to good environmental subjects: public contest and personal struggle over
appropriate environmental action. Paper presented at the American Anthropological Association 98th
Annual Meetings, Chicago, IL (Panel Title: New Social Movements and the Local: Developing
Environmental Identities and Structures for Social Change).
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Daro, V.E. 1999. Is it getting hot in here or is this a fever setting in? Life in the greenhouse at the turn of
the century. Course paper for Science, Technology and Anthropology, Professor Peter Redfield, UNC,
Chapel Hill.
Daro, V.E. 1999. The woman who climbed up the tree and stayed there. Course paper for Environmental
Consciousness and Action, Professor Dorothy Holland, UNC, Chapel Hill.
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U915331
AQUEOUS SILICA IN THE ENVIRONMENT: EFFECTS ON IRON HYDROXIDE SURFACE
CHEMISTRY AND IMPLICATIONS FOR NATURAL AND ENGINEERED SYSTEMS
Christina C. Davis
Virginia Polytechnic Institute and State University
Objectives/Hypotheses: The work was aimed at characterizing iron hydroxide surfaces produced after
contact with varying levels of silica in the pH range of 5.0-9.5, and determining how silica impacts removal
of arsenic during coagulation. An additional objective was to determine whether existing sorption models
could explain key trends in the data and to propose a new model conceptualization if necessary.
Rationale; Silica is omnipresent in U.S. drinking water supplies, typically at 1 -20 mg/L for surface water
and 7-45 mg/L for groundwater. Previous work indicated that soluble silica in natural systems occurred
exclusively in the form of monosilicic acid and its conjugate base. However, more recent research using
NMR has established new equilibrium constants that suggest up to 50% of the total soluble silicon
concentration in natural waters is present in dimeric silica species. Several studies have established that
soluble silica exhibits high affinity for surfaces of aluminum and ferric oxides, and formation of multiple
layers of sorbed si lica has been observed in these systems. The general hypothesis was that monomeric silica
species, specifically monosilicic acid and its conjugate base, were sorbing to the surfaces and sequentially
forming layers. If dimeric silica species in solution have an extremely high affinity for iron and aluminum
oxide surfaces, they might contribute to significant adverse effects on coagulation associated with silica.
The presence of polymeric silica is known to hinder precipitation of iron and manganese, and silica was
recently shown to interfere with arsenic removal by coagulation,
Approach: Experiments were designed to investigate the fundamentals of silica sorption onto pre-formed
ferric hydroxide (10 mg/L as Fe) at pH 5.0-9.5 and silica concentrations of 0-200 mg/L. The silica sorption
density and zeta potential of each sample were measured after 1.5 hours and 50 days of reaction time.
Additional experiments will explore arsenic removal with ferric chloride in the presence of silica.
Status: Experiments to characterize the iron-silica surface have been completed, and an extended surface
complexation model was developed. Experiments to determine the effect of silica on arsenic removal during
coagulation are nearing completion.
Papers & Publications: Davis, C.C., Chen, H.-W., and Edwards, M. The role of silica sorption in iron
hydroxide surface chemistry. Environ Sci Techno! (in preparation)
Davis, C.C. and Edwards, M. Implications of silica sorption to iron hydroxide: mobilization of iron colloids
and interference with sorption of arsenate. Environ Sci Technol (in preparation)
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U91515S
USING RADAR TOMOGRAPHY, HYDRAULIC TESTS, AND TRACER EXPERIMENTS
TO CHARACTERIZE FRACTURED-ROCK FLOW SYSTEMS
Frederick D. Day-Lewis
Stanford University
Objectives/Hypotheses: To develop a unified approach to the analysis of multiple data types in fractured rock,
including hydraulic tests, tracer experiments, and cross-well radar tomography. A key component of this
research is to combine attenuation-difference radar tomography and numerical models of ground-water flow
and solute transport to monitor the migration of an electrically-conductive tracer and estimate the hydraulic and
transport properties of permeable pathways.
Rationale: Combining different types of data yields more reliable images of subsurface properties than
independent analyses of the individual data sets. This research indicates how joint analysis of multiple data
types can be used to identify subsurface architecture and hydraulic properties in a moderately non-invasive
manner. The approach demonstrates the use of innovative geophysical techniques to infer hydraulic properties,
and provides a cost-effective tool for site characterization that takes advantage of multiple sources of data.
Approach: The approach to combining multiple data types for subsurface characterization has four
components. The first involves geostatistical simulation to generate realizations of fracture-zone distribution
consistent with packer-tests estimates of hydraulic conductivity, inferred hydraulic connections, and any
available soft data. The second component is a set of simulation models for flow and solute transport. Third,
tomographic inverse methods are used to image the movement of an electrically conductive tracer. Last is a
stochastic optimization algorithm to link the first three components and calibrate the geostatistical realizations
to the various types of data in a manner consistent with the physical processes underlying the experimental data.
The ensemble of calibrated realizations provides a model of uncertainty, given the scarcity and resolution of
the data. By applying the method to subsets of the available data, the worth of different types of information
may be explored. Data comes from the USGS Fractured-Rock Hydrology research site near Mirror Lake, in
Grafton County, NH.
Status: The first stage of my research is finished. This work was presented at a meeting of the USGS Toxic
Substances Hydrology Program, and a manuscript was accepted for publication in Water Resources Research.
A journal manuscript on the geophysical results is in preparation. I expect to complete the final stage of this
project by December 2000.
Papers & Publications: Day-Lewis, F.D., Hsieh, P. A., and Gorelick, S.M. Identifying fracture-zone geometry
using simulated annealing and hydraulic-connection data. Water Resources Research (in press)
Day-Lewis, F.D., Hsieh, P.A., Shapiro, A.M., and Gorelick, S.M. 1999. Geostatistical simulation of high-
transmissivity zones at the Mirror Lake Site in New Hampshire: conditioning to hydraulic information. In:
Morganwalp, D.W. and Buxton, H.T., eds. U.S. Geological Survey Toxic Substances Hydrology
Program—Proceedings of the Technical Meeting, Charleston, SC, March 8-12,1999. Vol. 3 of 3: Sub-surface
Contamination from Point Sources: U.S. Geological Survey Water-Resources Investigations Report 99-4018C
pp. 685-694.
Day-Lewis, F.D., Lane, J.W., Jr., Haeni, P.P., and Gorelick, S.M., 1997. One approach to identifying flow
paths in fractured rock—combining borehole radar, saline tracer tests, and numerical modeling: EOS,
Transactions, American Geophysical Union 78(46) :F322.
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U915651
EFFECTS OF LOGGING ON UNDERSTORY PLANT DIVERSITY
IN NORTHERN HARDWOOD FORESTS
Daniel R. DeJoode
University of Michigan
Objectives/Hypotheses; Research goals are to: 1) document community patterns of vascular plant diversity
in logged and unlogged forests; 2) describe how different species groups, defined by life history attributes,
respond to logging; and 3) test hypotheses to explain why certain species groups are negatively affected by
logging.
Rationale; Logging affects millions of hectares of forests worldwide. Theories of forest succession, that
can help understand ecological effects of logging, focus tree species composition and regeneration with little
attention to the understory community. However, in eastern North American temperate forests, understory
species represent a larger contribution to total species diversity than tree species (i.e., only 15-20 percent of
all vascular plants are trees). Understory species grow, reproduce, and disperse at different spatial and
temporal scales than tree species. Because understory plants comprise such a large proportion of forest
species diversity, their contribution to forest succession dynamics needs to be better understood for both
completeness of forest ecology theory and for conservation and management objectives.
The empirical literature on the effects of logging on understory plant communities does not provide clear
indications of trends. Some authors report no significant changes in understory diversity after clearcutting
other than a short-term flush of fast-growing, shade-intolerant pioneer species that disappear when
regenerating saplingsexclude light from the understory. Conversely, others suggest that understory diversity
declines after logging and remains depressed for decades. Some of these discrepancies may be due to
methodological differences (e.g., sampling at different spatial scales or in different seasons), different
analytical techniques, different forest types, or different forest histories.
Approach: Botanical surveys have been conducted on numerous logged stands and adjacent unlogged
mature forest stands on the Menominee Indian Reservation in northeast Wisconsin. This includes stands that
have been subject to different silvicultural techniques ranging from single tree selective harvest to small
scale (5-10 ha) clearcuts. Ongoing work includes sampling stands before and after logging to more precisely
document the type and rate of changes in the plant community and experiments to explain the response of
certain species.
Status; Experiments are currently underway to test hypotheses to explain why ant-dispersed species are less
common after logging. Hypotheses include increased plant mortality and decreased reproduction and the
breakdown of the ant-plant mutualism after logging. If the seed dispersal mutualism is disrupted, the ability
of plant populations to recolonize and recover in logged areas will be limited. These experiments will be
conducted during the 2000-2001 growing seasons.
Papers & Publications: None at this time.
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STAR Graduate Fellowship Conference
U915605
VOICES FROM THE MOUNTAINS: CHILDREN'S SENSE
OF PLACE IN NORTHERN NEW MEXICO
Victoria L. Derr
Yale University
Objectives/Hvpotheses; My primary objectives in this research were to examine children's place
experiences within the specific social, cultural, and ecological context of three communities within northern
New Mexico. Through this research, I address the questions: 1) Is there an "extinction of experience"? (i.e.,
do children really have diminished experiences with nature?) 2) Is it the nature of experience or the
experience of nature that matters? (i.e., is this a romanticized notion or does nature provide something unique
and important to children?) 3) What are place attachments made of and why do they matter? (i.e., do they
provide psychological benefits to children and do they create caring behavior toward the environment?)
Rationale; Within the field of environmental education, the concepts of "place," "place attachments," and
a "sense of place" have recently received wide attention. Curricula are developed to connect children with
places, assuming that if children care about one place in particular, they will eventually care about the
environment in general. There is concern that children are facing an "extinction of experience" with nature;
that the opportunities for direct and intimate contact with localized places rarely exist for children today.
Yet, most of these ideas have not been substantiated with actual research. And of the research that has been
conducted, little has been with youth, and few studies look at children within the social, cultural and
ecological context of their experiences. In addition, though some regional or city plans have attempted to
include children's environmental needs, most planning overlooks children, children's special places, and the
kinds of experiences children need in order to feel attached to places and to care about them in the future.
Approach; My approach has been primarily ethnographic. During an exploratory phase of research, I used
mapping, composition analysis, and semi-structured interviews with children in three communities (one
urban and two rural). In a more in-depth phase of research, I used interviews and place expeditions with
focus children and conducted interviews with parents and grandparents of these children.
Status: (Not received at time of printing.)
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915221
ECOLOGICAL STRATEGIES OF BACTERIA
AND THE EFFICIENCY OF PROTEIN SYNTHESIS
Les Dethlefsen
Michigan State University
Objectives/Hypotheses; 1) Determine whether the pattern of an increased efficiency of protein synthesis
with increasing growth rate, established for enteric bacteria, also exists in other bacteria. 2) Determine
whether the relationship between protein synthesis efficiency and growth rate differs for bacterial strains
with different ecological strategies.
Rationale; Ribosome concentration increases linearly with growth rate in moderately to rapidly growing
cultures of enteric bacteria, but is relatively insensitive to growth rate in slowly growing cultures. Protein
synthesis efficiency (the rate of protein synthesis per RNA) is approximately constant at moderate to rapid
growth rates, but varies directly with growth rate at slower growth rates. Various aspects of this pattern have
been proposed to be adaptive traits resulting from different (and conflicting) selective forces thought to act
on bacterial populations. The proposed adaptations include: 1) a capacity for rapid growth when nutrients
are abundant, 2) a capacity for a rapid increase in growth rate when nutrient availability increases, and 3)
minimal resource investment in the protein synthesis system. However, no investigation to date has sought
to determine whether bacterial strains adapted to different ecological conditions, and therefore subject to
different selective pressures, might display different patterns of protein synthesis efficiency as a function
of growth rate. A review of all published data suggests that there may be a consistent difference in the
relationship of protein synthesis efficiency to growth rate between gut bacteria and soil/sediment bacteria.
In comparison to the soil/sediment bacteria, the gut bacteria have higher protein synthesis efficiency at all
growth rates and a greater increase in protein synthesis efficiency as growth rate and RNA content increases.
However, this survey suffers from potential systematic errors and a lack of phylogenetic breadth. My
research will use a diverse collection of bacteria with contrasting ecological strategies to investigate whether
ecological factors influence the relationship between protein synthesis efficiency and growth rate.
Approach; I am working with a collection of soil bacterial isolates selected to represent two contrasting
ecological strategies: a rapid maximal growth rate and rapid response to nutrients vs. slow maximal growth
rate and a delayed response to nutrients. In addition, I am using several well-characterized bacterial strains
known to represent examples of these strategies. The strains will each be grown in pure culture in the lab
at a range of defined growth rates. Measurements will include the RNA, DNA, and protein content of the
bacteria, as well as cell volume, abundance, and biomass. Protein synthesis efficiency will be calculated as
a function of growth rate to test the following hypotheses: 1) rapidly responding strains will have a higher
protein synthesis efficiency overall than slowly responding strains, and 2) rapidly responding strains will
have a greater increase in protein synthesis efficiency as their growth rate increases than slowly responding
strains.
Status: In progress.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915226
POTENTIAL IMPACTS OF TRANSGENIC POPLAR CULTIVATION
Stephen P. DiFazio
Oregon State University
Objectives/Hypotheses; I am exploring potential environmental impacts of widespread cultivation of
genetically engineered hybrid poplar (Populus spp.) trees. Specific goals include determining current levels
of gene exchange between poplar plantations and wild stands, characterizing establishment of hybrid pop-
lars, simulating potential spread of transgenic trees, and evaluating potential impacts.
Rationale; Tree genetic engineering raises significant safety concerns, including the possibility that the
engineered trees will become invasive pests, that competitiveness of wild relatives will be altered through
introgression of the transgene, and that the transgene product will have negative impacts on natural
populations and ecosystems. Forest trees pose difficult obstacles for genetic risk analysis because of their
long generation times, large size, and potential for long-distance dispersal of pollen and seed. We must,
therefore, use established stands for retrospective studies of gene flow, and simulation models to explore the
consequences of introducing new genes into the environment.
Approach; I am using a combination of morphological and molecular markers to track seed and pollen
movement from several hybrid poplar plantations in Oregon, and to monitor establishment and growth of
hybrid seedlings in the vicinity of plantations. Using data from these gene flow studies and a spatial database
derived from digitized air photos, I am developing a spatial simulation model to explore the complex
processes involved in gene escape.
Status: Thus far, I have determined that gene flow has occurred between hybrid plantations and wild trees
at a low level (of 12,000 seedlings assayed, 49 were of hybrid origin (0.4%)). Also, there is no evidence of
competitive inferiority of hybrid progeny compared to wild trees: hybrids grew equally well or better than
wild progeny in experimental plots and in a common garden. I have also begun developing the spatial
simulation model by obtaining a digitized map of cottonwood populations in the vicinity of plantations in
my study area. Data structures are in place and model preprocessing is complete. All functions are outlined,
and coding is underway. The entire project will be completed by the end of the year.
Papers & Publications; Brunner, A., Rottmann, W.H., Sheppard, L.A., Krutovskii, K., DiFazio, S.P.,
Leonard!, S., and Strauss, S.H. 2000. Structure and expression of duplicate AGAMOUS orthologs in poplar.
The Plant Journal (in press)
DiFazio. S.P., Leonardi, S., Cheng, S., and Strauss, S.H. 1999. Assessing potential risks of transgene escape
from fiber plantations. In: Lutman, P.W., ed. Gene flow and agriculture: relevance for transgenic crops.
Symposium Proceedings No. 72. British Crop Protection Council, Farnham, UK. pp. 171-176.
James, R., DiFazio, S.P., Brunner, A., and Strauss, S.H. 1998. Environmental effects of genetic engineering
of woody biomass crops. Biomass & Bioenergy 14(4):403-414.
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U915655
ENVIRONMENTAL INFLUENCES ON INSECT FLIGHT PERFORMANCE
Michael E. Dillon
University of Washington
Objectives/Hypotheses; Using a morphologically diverse group of tropical bees, the limits to flight
performance using a load-lifting method have been assessed and compared to other flight performance
assays. Initial findings suggest that bees possess large performance reserves that can be tapped during
demanding flight situations, perhaps insulating the bees from the effects of small-scale changes in the
physical environment. This work serves as a first step to investigating the relationship between flight and
the physical properties of air.
Rationale; As the most diverse and numerous class of metazoan organisms on earth with over 750,000
described species, insects dominate the terrestrial biosphere. Since greater than 99% of insect species are
pterygotes, the ability to fly has been regarded as a crucial factor in their success. Flight is dependent on
both abiotic and biotic factors. Global changes in atmospheric gas composition, temperature and insolation
potentially affect flight as much as do interactions with conspecifics, predators, and resources. The study
of how physical changes in the environment affect insect flight provides a broadly relevant perspective on
biotic responses to global change.
Approach; The study of flight performance of a morphologically diverse group of insects provides a
description of what structural diversity is functionally relevant to flight. Changes in relevant structure can
then be correlated with changes in flight performance. Using a combination of laboratory and field studies,
I will study how physical changes in the flight medium engender concomitant changes in morphology. I will
systematically vary the physical properties of air-density, viscosity, and temperature in the lab and measure
organism response in terms of flight performance. I will then examine evolutionary responses to natural
variations in the flight medium by analyzing morphological diversity across altitudinal and latitudinal
gradients. By integrating results from the two approaches, I hope to shed light on how global change can
affect a large proportion of the earth's organisms.
Status; I am currently in my first year of work on this project. I have modified several techniques for
measuring flight performance, and examined the validity of the methodologies in detail. Preliminary work
has also provided a detailed portrait of the amount and types of morphological diversity that may be
functionally relevant in the orchid bees. Over the next 2Vi years, I hope to have detailed flight performance
data on a focus group of insects under widely varying physical conditions which I plan to integrate with data
on morphological variation across natural gradients.
Papers & Publications; Chai, P., Altshuler, D.L., Stevens, D.B., and Dillon, M.E. 1999. Maximal
horizontal flight performance of hummingbirds: effects of body mass and molt. Physiological and
Biochemical Zoology 72(2): 145-155.
Dillon, M.E. 1997. Kinematics and aerodynamics of hummingbirds in forward flight. Proceedings of the
National Conference on Undergraduate Research.
Dillon, M.E. and Dudley, R. Load-lifting in euglossine bees (Apidae: Euglossini): methodology and
allometry of performance, (in preparation)
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Dillon, M.E. and Dudley, R. Load-lifting in euglossine bees (Apidae: Euglossini): intraspecific variation
in morphology and power output, (in preparation)
Dudley, R. and Dillon, M.E. Load-lifting in euglossine bees (Apidae: Euglossini): interspecific variation
in morphology and power output, (in preparation)
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STAR Graduate Fellowship Conference
U915421
DYNAMICS OF PIONEER FORESTS ALONG THE WISCONSIN RIVER: LANDSCAPE,
LOCAL, AND TEMPORAL FACTORS
Mark D. Dixon
University of Wisconsin
Objectives/Hypotheses; The objective of this research is to understand the linkage between riparian
vegetation dynamics and variation in river flow processes, in space and time. My project has three major
questions: 1) what are the effects of physical factors at local (quadrat) and landscape (sandbar, channel, and
river reach) scales on the distribution of seedlings of pioneer riparian trees? 2) What are the effects of
variation in flow timing and magnitude on seedling establishment and species composition? 3) Can episodes
of past woodland establishment be reconstructed through modeling the relationship between river flow and
seedling recruitment?
Rationale; Riparian systems are valuable habitats for the conservation of biodiversity and for the buffering
of land use impacts on aquatic systems. Dynamics of riparian forest, particularly of pioneer species, are
closely related to the magnitude, pattern, and timing of river flow. Thus, shifts in the species composition
and age structure of riparian forest may be closely tied to alterations in the fluvial environment.
Understanding the link between forest regeneration and river flow patterns may be useful for predicting the
response of riparian habitats to climate change, flow management by dams, or to other natural or human
alterations of river hydrology.
Approach; Question 1 was addressed in 1998 through field sampling of seedlings and topography on newly
colonized sandbars within a 16-km reach of the Wisconsin River, and by analysis of the effects of physical
factors at different scales on seedling occurrence and abundance. Question 2 is being addressed by annual
(1997-2000) surveys of seedling species composition and elevation relative to river stage. To answer
question 3, the interactions between flow and seedling establishment will be modeled and used to predict
the suitability of conditions in different years to recruitment and survival of different seedling species.
Model predictions will be tested by comparing known establishment years of seedlings, saplings, and trees
with years of seedling establishment predicted by the model, based on historic flow records.
Status; I have submitted a manuscript based on question 1, and will soon submit one on question 2.
Completion of all research questions is expected by the end of spring semester 2001.
Papers & Publications; Dixon, M.D., Turner, M.G., and Jin, C. Distribution of riparian tree seedlings on
Wisconsin River sandbars: controls at different spatial scales. Ecology (submitted)
Dixon, M.D. Temporal variation in seedling composition on Wisconsin River sandbars, (in preparation)
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STAR Graduate Fellowship Conference
U915583
THE USE OF ALFALFA (MEDICAGO SATIVA) TO RECOVER
CHROMIUM(III) AND CHROMIUM(VI) FROM AQUEOUS SOLUTION
Kenneth M. Dokken
University of Texas, El Paso
Objectives/Hypotheses; The goal of this project is to develop a cost effective, environmentally friandly
phytofiltration system using Alfalfa (Medicago saliva) to recover trivalent and hexavalent chromium from
contaminated waters.
Rationale: The demand for products that contain or utilize Cr(III) and Cr(VI) has increased over recent
years causing an increase in chromium waste, which poses a health threat to the public. Current technologies
such as ion exchange resins are expensive and require the use of hazardous chemicals for their production.
The use of plant biomass may be a possible alternative to current filtration technologies. Alfalfa is a
biosorbent that possesses a high affinity for Cr(III) and Cr(VI) as well as other metals like Cu(II) and Pb(II).
Alfalfa is an easily attainable and inexpensive plant. This study employs the use of the dead or inactivated
alfalfa biomass instead of the live plant, which reduces costly maintenance as well as time. Another benefit
of using inactivated plant tissues lies in their reuse after recovery of the chromium from contaminated
waters. By using a stripping agent, it is possible to recover the majority of the bound chromium from the
inactivated alfalfa biomass. This provides the system with the advantages of recyclibility and possible reuse
of the chromium recovered.
Approach; Batch experiments have been conducted to determine optimal binding pH, temperature, and
time. Capacity studies have been performed to determine the amount of chromium the biomass can adsorb
(mg chromium/g biomass). Modification studies that involve esterifying and hydrolyzing the biomass were
conducted to help ascertain which ligands might play an important role in chromium binding. In addition,
flow studies were conducted using silica immobilized biomass. A chromium solution is pumped through
a column containing the silica immobilized biomass and the effluents are collected and analyzed for
chromium concentration. X-ray microfluorescence studies were performed to further prove that the
chromium binds to the alfalfa biomass, as indicated by the batch studies. X-ray absorption spectroscopy
(XAS) studies were conducted at the Stanford Synchrotron Laboratories to help characterize the binding
mechanism(s) involved in the binding of Cr(III) and Cr(VI) by the alfalfa biomass. Two XAS techniques
were utilized: X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine
Structure (EXAFS). These techniques determine the oxidation state of the chromium being bound to the
biomass and the ligands that chromium may be binding to on the surface of the biomass.
Status: Since our previous work indicated that Cr(III) was difficult to desorb after being bound to the alfalfa
biomass, our current focus has been desorption of the bound chromium through environmentally safe
methods. A study of stripping agents, that includes dilute acids, bases, and salts, is being conducted in order
to obtain maximum chromium recovery. Following the indemnification of a proper desorption method for
bound chromium, the system may be tested with actual chromium contaminated waters.
Papers & Publications; Gardea-Torresdey, J.L., Tiemann, K.J., Gamez, G., Dokken, K., Sias, S., Renner,
M. W., and Furenlid, L.R. 1999. Use of x-ray absorption spectroscopy and esterification to investigate Cr(III)
and Ni(II) ligands in alfalfa biomass. Environ Sci Technol 33:150-154.
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STAR Graduate Fellowship Conference
U915309
ANALYSIS OF DERMAL EXPOSURE TO PESTICIDE RESIDUES
Ed M. Doran
University of Washington
Objectives/Hypotheses: Agricultural workers have the potential for prolonged extensive contact with
pesticide residues. Unfortunately, dermal absorption of these compounds can significantly impair the health
of the worker. Therefore, regulators and public health professionals frequently rely on dermal absorption
models to predict the risks that result from an occupational exposure. Although there are a number of models
available to estimate the magnitude or rate of dermal absorption, there is very little data to evaluate the
predictions.
Rationale; Our studies were designed to analyze the ability of dermal exposure models to accurately
estimate dermal absorption of an organophosphate pesticide.
Approach: We have used both field and laboratory data to evaluate the predictions of dermal exposure
models.
Status; We are preparing our analyses for publication.
Papers & Publications; None at this time.
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U915308
CONSERVATION GENETICS AND SYSTEMATICS OF STURGEON
Phaedra Doukakis
Yale University
Objectives/Hypotheses; The three main goals of the project are to understand the systematic relationships
among sturgeons and paddlefishes (Order Acipenseriformes), develop forensic methodology to identify the
species origin of caviar for Ponto-Caspian species, and characterize infraspecifc structure and hatchery
population integrity within commercial sturgeon species.
Rationale: Sturgeons and paddlefishes represent an ancient lineage with a fossil record dating to the
Jurassic. Seriously threatened by overharvest for caviar and habitat degradation, many species are now listed
under the Endangered Species Act (ESA) and/or Convention on International Trade in Endangered Species
(CITES). Although forensic methodology is now available to identify the species origin of caviar and
thereby regulate the international caviar trade, certain Ponto-Caspian species (Acipenser baerii, A.
gueldenstaedtii, A. naccarii, A. persicus) still cannot be differentiated using current techniques. While
international regulation has helped to curb the illegal caviar trade, population sizes of the main commercial
species (A. gueldenstaedtii, A. stellatus, Huso huso) continue to decline. Development of a sustainable
harvest management plan is currently hindered by insufficient knowledge of population structure. As fishes
generally exhibit extensive phenotypic plasticity and morphological identification of the species origin of
caviar has proven unreliable, molecular tools have been employed in addressing the project goals.
Approach; The 12S, 16S, 18S, NADH5, cytochrome b, and D-loop mitochondrial DNA gene regions have
been sequenced and screened for variability at the different levels of inquiry (genus, species, subspecies).
Segments of all gene regions were used for the phylogenetic study, while only the NADH5, cytochrome b,
and D-loop gene regions were used for forensic and infraspecific work. Sampling for each project has
included individuals from a wide geographic range for each species. Phylogenetic analysis has included
maximum parsimony, maximum likelihood and minimum evolution-based approaches, while forensic and
infraspecific studies have examined diagnostic differences, private alleles, and gene flow among species and
subspecies, as well as mtDNA phylogeographic structure.
Status: One manuscript has been submitted concerning forensic methodology and two additional papers
are in progress detailing the results of the two other projects.
Papers & Publications: Birstein, V.J., Doukakis, P., Sorkin, B., and DeSalle, R. 1998. Population ag-
gregation analysis of caviar-producing species of sturgeons and implications for the species identification
of black caviar. Conservation Biology 12:766-775.
Birstein, V.J., Doukakis, P., and DeSalle, R. 1999. Molecular phylogeny ofAcipenserinae and black caviar
species identification. J Appl Ichthyol 15:12-16.
Doukakis, P., Birstein, V.J., and DeSalle, R. 1999. Molecular genetic analysis among subspecies of two
Eurasian sturgeon species, Acipenser baerii and A stellatus. Molecular Ecology 8(S 12): 117-129.
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U915304
CONFIRMED DETECTION OF CYCLOSPORA CAYETANESIS
AND ENCEPHALITOZOON INTESTINALIS IN WATER USED FOR DRINKING
Scot E. Dowd
University of Arizona
Objectives/Hvpotheses; HumanenteropathogenicmicTOSporidia(t{EM),Cryptosporidiumparvum,Cyclo-
spora cayetanesis, and Giardia lamblia are associated with gastrointestinal disease in humans. To date, the
mode of transmission and environmental occurrence of HEM (Encephalitozoon intestinalis and Entero-
cytozoon biemusi) and Cyclospora cayetanesis have not been fully elucidated due to lack of sensitive and
specific environmental screening methods. The present study was undertaken, with recently developed
methods, to screen various water sources used for public consumption in rural areas around the city of Guate-
mala. Water concentrates collected in these areas, that showed presumptive visual identification of the
protozoa, were subjected to community DNA extraction followed by PCR amplification, PCR sequencing,
and computer database homology comparison (CDHC). All water samples screened in this study had been
previously confirmed positive for Giardia spp. by immunofluorescent assay (IFA). Of the 12 water con-
centrates screened, 6 showed amplification of microsporidial SSU-rDNA and were subsequently confirmed
to be Encephalitozoon intestinalis. Five of the samples allowed for amplification of Cyclospora 18S-rDNA
and three of these were confirmed to be Cyclospora cayetanesis, while two could not be identified because
of inadequate sequence information. Thus, this study represents the first confirmed identification of
Cyclospora cayetanesis and Encephalitozoon intestinalis in drinking water. The fact that the waters tested
may be used for human consumption indicates that these emerging protozoa may be transm itted by ingestion
of contaminated water in these areas.
Rationale: (Not received at time of printing.)
Approach; (Not received at time of printing.)
Status; (Not received at time of printing.)
Papers & Publications; (Not received at time of printing.)
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STAR Graduate Fellowship Conference
U915393
EARLY POSTNATAL LEAD EXPOSURE ALTERS THE GABAERGIC
MODULATION OF SUSTAINED ATTENTION
Lori L. Driscoll
Cornell University
Objactives/Hypotheses: This project utilizes a rodent model of human neurobehavioral development to
test the hypotheses that: 1) developmental lead (Pb) exposure produces impairments in sustained attention
but does not affect inhibitory control; and 2) Pb's effects on attention are in part mediated by changes in the
GABAergic inhibition of cortical acetylcholine release.
Rationale: Epidemiological researchers have reported links between developmental Pb exposure and
neurocognitive deficits in children for decades. One of the cognitive abilities thought to be most affected
in exposed children is attention. However, findings of attentional dysfunction in Pb-exposed children are
largely based upon subjective teacher or guardian ratings in the absence of definitive impairment on specific
cognitive tests of attentional function. The present study is designed to bridge the gap between
epidemiological accounts of Pb's effects on attention and experimental evidence of Pb's effects on one
specific aspect of attention, namely, sustained attention or vigilance. In addition, this study attempts to link
Pb-induced cognitive impairments with underlying changes in GABAergic function. Elucidation of the
neural mechanisms underlying Pb's effects is vital for the development of pharmacological therapies to
alleviate long-term effects of developmental Pb exposure.
Approach; Female Long-Evans rats (n=47) were randomly divided into three treatment groups. Lactational
Pb rats were exposed to Pb in their drinking water from birth through postnatal day 30, Chronic Pb rats
received Pb water from birth through adulthood, and Control rats were given tap water. An automated
vigilance task, in which brief light cues were presented over three funnel-shaped ports, was utilized in the
assessment of sustained attention. The animals were food reinforced for making a nosepoke into the funnel
under which the light cue appeared. Cues were presented after an unpredictable delay period (0,3,6, or 9
s) and for an unpredictable cue duration (200, 400, or 700 ms) in order to increase attentional demand.
Choice accuracy and errors of omission (i.e., failures to respond to the cue) served as measures of sustained
attention, while responses made prior to cue presentation constituted failures of inhibitory control.
Following an extended period of training in the vigilance task, manipulations of GABAergic function were
accomplished by orally administering the benzodiazepine agonist chlordiazepoxide (CDP) 30 minutes prior
to testing. Drug administrations took place once per week, and every subject received each of the four doses
(0, 5,8, and 12 mg/kg of body weight) in a randomized order. Dose-response curves were calculated for the
three treatment groups; shifts in the dose-response curve were interpreted as evidence for Pb-induced
changes in GABAergic modulation of attentional performance.
Status; Chlordiazepoxide (CDP) improved accuracy and reduced omission errors in the sustained attention
task for all treatment groups; however, it also increased premature responses, suggesting that along with
improving attention, it also impaired inhibitory control. Although the Pb-exposed animals were not impaired
in the sustained attention or inhibitory control aspects of the task in the non-drug state, both Lactational Pb and
Chronic Pb rats demonstrated increased sensitivity to CDP compared to Control rats in measures of sustained
attention. Possible mechanisms underlying this specific increase in sensitivityincludePb-induced upregulation
of GABAA receptor number or downregulation of G ABA release in the basal forebrain, both of which could
lead to an increased sensitivity to GABAergic agonists. Future studies coupling microinfusions of CDP into
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the forebrain and immunocytochemical localization of GABAergic receptors will be designed to answer these
questions.
Papers & Publications; Driscoll, L.L. and Strupp, B.J. 1999. Chronic lead exposure produces subsen-
sitivity to the motor but not the mnemonic effects of MK-801. Soc Neurosci Abs 24(1):366.
Driscoll, L.L., Gardner, S.A., Beaudin, S., and Strupp, B.J. 1999. Enduring effects of early lead exposure
in a vigilance task: contribution of cholinergic alterations. Neurotoxicol Teratol 21(3):285.
Strupp, B.J., Driscoll, L.L., Beaudin, S., Hermer-Vazquez, L., Morgan, R.E., and Caravan, H. 1999. Early
lead (Pb) exposure: the emerging cognitive profile. Neurotoxicol Teratol 21(3):285.
Driscoll, L.L., Wu, J.J., Zurich, K.J., and Strupp, B.J. 1999. Chronic lead exposure alters explicit memory
function. Toxicol Sci 48(1-S):360.
Driscoll, L.L., Gilbert, M.E., and Strupp, B.J. 1998. Cholinergic and noradrenergic modulation of long-term
explicit memory are altered by chronic low-level lead exposure. Neurotoxicol Teratol 20:195.
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U9J5355
RELATIONSHIP BETWEEN RATES OF LIGAND-PROMOTED DISSOLUTION
OF HEMATITE AND THE IRON-LIGAND SURFACE STRUCTURES
OF Cl TO C6 DICARBOXYLIC ACIDS
Owen W. Duckworth
University of North Carolina
Objectives/Hypotheses; In the present work, the dissolution rates of hematite exposed to a homologous
series of ligands are measured. The molecular surface structures are assigned through the infrared spectra.
We test the hypothesis that faster rates are associated with ligands forming bidentate mononuclear surface
structures, while monodentate ligands passivate the surface.
Rationale: The dissolution of iron oxide coatings on aquifer material consumes protons and releases ferric
ions. In some circumstances, the dissolution rate is sufficiently rapid to be the "master reaction" in the
complex coupled geochemical and biological chemical kinetic system that regulates the "master variables"
Eh and pH in groundwater. Proton consumption and ferric ion release accompany hematite (Fe203)
dissolution, as follows: 1) Fe2O3 + 6H+ -* 2Fe3+ + 3H20 - Reaction 1 is stow at common groundwater pH
values. Instead, dissolution usually proceeds via faster ligand-promoted pathways, as follows: Fe2O3 4- 2
OOC(CH2)nCOO2- 4- 6H+ -* 2[Fe(III) - OOC(CH2)nCOO]+ + 3H2O. The oxygenated organic ligands are
released by microbes and plant roots to labilize nutrients, including aqueous iron. The ligands form
inner-sphere complexes with surficial FeOH groups and promote the release of Fe(lll) from the oxide lattice.
Approach; Hematite suspensions are synthesized by the forced hydrolysis of FeC13*6H2O at 98° C re-
fluxed for 7 days, Once centrifuged decanted to remove HC1, a typical batch yields 1.0 g solid. The
crystallinity, morphology, and surface area of the particles is studied by selective area electron diffraction
(SAED), transmission electron microscopy (TEM), and BET analysis of the N2 adsorption isotherm,
respectively. In a typical dissolution experiment, the reactor contains a sonnicated hematite suspension, 10
mM of the desired ligand, and 5 mM of acetate buffer at pH = 5.0. The reactor vessel is a bell jar immersed
in a constant temperature bath. The top piece of the reactor has feed-throughs for an overhead stirrer, a gas
sparger, a sampling port, and a pH electrode. Argon, passed through a humidifier, sparges the suspension
exclude atmospheric CO2. Aluminum foil, encasing the apparatus, provides a light shield. The reactor is
sampled ten times in 72 hours by removing 7 mL aliquots and filtering through 0.2 micron membrane
syringe filters. In this way, the aqueous iron is separated from the suspended particles. Aqueous iron is
quantified by inductively coupled plasma atomic emission spectroscopy (ICP-AES). To measure infrared
spectra of surface structures, the crystal element (ZnSe) is coated with hematite crystals. The total mass of
hematite applied to the surface is approximately 3 ing. Spectra are taken with deionized water and aqueous
ligand By subtracting the water spectra from the aqueous ligand spectra, the signal for the adsorbed ligand
can be detected. Singular value decomposition is employed to determine the number of surface structure
present for each ligand.
Status: Up to this point, work has focused on macroscopic rates of dicarboxylate-promoted dissolution.
Future work will focus on a microscopic perspective on mineral dissolution using atomic force microscopy.
Papers & Publications: None at this time.
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STAR Graduate Fellowship Conference
U915383
PROSPECTS AND POLICIES FOR RESIDENTIAL THIN-FILM PHOTOVOLTAIC ROOFING
Richard D. Duke
Princeton University
Objectives/Hypotheses: We estimate the costs involved in the manufacture of amorphous silicon photo-
voltaic modules and whether a net metering law at the federal level could induce the development of one or
several 100 MWp manufacturing facilities.
Rationale; Thin-film photovoltaic modules provide clean distributed electricity; however, at present they
are not cost-effective in central-station grid-connected applications. The residential rooftop market offers
a potentially large near-term market niche because of the relatively high value of electricity produced on-site
in residential areas.
Approach; When discussing the costs of manufacturing photovoltaic (PV) modules, indirect costs and
financing costs are frequently neglected because they are less quantifiable. Indirect costs and financing costs
each carry roughly the same weight as the direct manufacturing costs and we, therefore, include and highlight
these factors in our assessment.
Status; I am lead author, along with Adam Payne and Robert H. Williams, for one of two publications based
on this analysis that we will submit for possible publication by the journal Energy Policy.
Papers & Publications; Duke, R.D. and Kammen, D.M. 1999. The economics of energy market trans-
formation initiatives. The Energy Journal 20(4): 15-64.
Duke, R.D., Graham, S., Hankins, M., Jacobson, A., Kammen, D.M., Osawa, B., Pulver, S., and Walther,
E. 2000. Field performance evaluation of amorphous silicon (a-Si) photovoltaic systems in Kenya: methods
and measurements in support of a sustainable commercial solar energy industry. For publication by the
World Bank, (in press)
Jacobson, A., Duke, R.D., Kammen D.M., and Hankins, M. 2000. Field performance measurements of
amorphous silicon photovoltaic modules in Kenya. Presented at the American Solar Energy Society
Conference in Madison, WI, June, 2000.
Duke, R.D. and Kammen, D.M. 1999. PV market transformation: the virtuous circle between experience
and demand and the strategic advantage of targeting thin-film photovoltaics. Paper presented at the IEA
Workshop on Experience Curves for Policymaking—The Case of Energy Technologies, Stuttgart, May
10-11, 1999.
Duke, R.D. and Kammen, D.M. 1999. Energy for development: solar home systems in Africa and global
CO2 emissions. Renewable and Appropriate Energy Laboratory, RAEL Number 99-1, prepared as a chapter
for forthcoming publication in Energy, Environment, and Sustainable Development in Africa, edited by Dr.
Pak Sum Low, UNFCCC Secretariat.
Kaufman, S., Duke, R.D., Hansen, R., Rogers, J., Schwartz, R., and Trexler, M. 2000. Rural electrification
with solar energy as a climate protection strategy. Renewable Energy Policy Project Research Report No.9,
January 2000.
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Duke, R.D. and Ryder, S. 2000. Green Lights. Case study in forthcoming Intergovernmental Panel on
Climate Change (IPCC) Special Report on Technology Transfer.
Greene, N., Duke, R.D., and Bryk, D. 1999. Regulating for renewable rural electrification. Natural
Resources Defense Council.
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U915547
PATHOGEN SURVIVAL IN DRINKING WATER DISTRIBUTION SYSTEMS
Nathaniel K. Dunahee
University of Illinois, Urbana-Champaign
Ob jectives/Hvpotheses; The main objective of this study is to investigate the mechanisms responsible for
the survival and the persistence of pathogens in the presence of a disinfectant residual in drinking water
distribution systems. Microorganisms used in this study include Aeromonas hydrophila, Mycobacterium
avium, and E. coli.
Rationale; The survival of pathogens in drinking water distribution systems is becoming a widespread
problem throughout the United States. Pathogens can enter a drinking water distribution system either from
cross contamination (a rupture in a drinking water pipe, consequently allowing contaminated water to enter)
or directly from the drinking water treatment facility due to insufficient disinfection. After pathogens enter
the distribution system, different mechanisms allow them to survive in the presence of a disinfectant residual.
These mechanisms involve exterior protection and shielding from the disinfectant residual resulting from
biofilms and other forms of protective barriers as well as an adaptive response that result from the cyclic
nature of the disinfectant concentration in a distribution system. This study will explore these mechanisms
and improve our understanding of how pathogens are able to survive in the presence of a disinfectant.
Approach; Experiments are designed to assess the role of cyclic and sequential exposure of the pathogens
(Aeromonas hydrophila and Mycobacterium avium) and the indicator organism (E. coli) to disinfectants.
Cyclic exposure will simulate the event of cross contamination when microorganisms are introduced into
a distribution system and are exposed to monochloramine, followed by loss of the disinfectant for a period
of time, and then re-exposed again. Experiments are performed using batch (when microorganisms are in
suspension) and flow through (when microorganisms are imbedded in biofilms) reactors at temperatures
between 1-30° C and at pH values between 6 and 8. Viability assessment is determined using serial dilutions
followed by the membrane filtration method (APHA et al., 1992).
Status; Results of experiments performed characterize the role of cyclic and sequential exposure to
disinfectants. The inactivation of E. coli from exposure to monochloramine was consistent with pseudo-first
order Chick-Watson inactivation kinetics. Results show that exposure to a strong pretreatment followed by
secondary exposure to monochloramine (sequential exposure) resulted with the rate of additional in-
activation by secondary exposure to monochloramine was approximately the same as that observed for
monochloramine alone (i.e., no synergy or inhibition). In contrast, exposure to lower level pretreatments
(cyclic exposure) resulted in no measurable primary inactivation as expected, while the rate of secondary
inactivation by monochloramine decreased substantially (i.e., increased resistance to the disinfectant). While
these experiments were performed with microorganisms in suspension, similar experiments are being
performed with microorganisms imbedded in biofilms. These data have been reproduced and confirmed
several times and help provide an explanation for the persistence of bacteria and pathogens in the presence
of the disinfectant residual in distribution systems.
Papers & Publications; None at this time.
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U915617
BACILLUS CEREUS UW85 AND TOMATO PLANTS:
A BIOLOGICAL CONTROL MODEL SYSTEM
Anne K. Dunn
University of Wisconsin, Madison
Objectives/Hypotheses: To betterunderstandtherelationshipbetween the bacterium Bacillus cereus UW85
and the plants it associates with through identification of bacterial genes that are regulated in the presence
of plant compounds.
Rationale; Our laboratory is interested in the use of plant disease-suppressing Gram-positive soil microbes
to supplement or replace traditional chemical pesticides. Bacillus cereus strain UW85 colonizes plant sur-
faces and suppresses diseases caused by pathogens on diverse plant species. By increasing our understanding
of the complex relationship between Gram-positive bacteria and their plant hosts, we hope to begin to
improve the efficiency and reliability of biological control as an environmentally safe supplement to
chemical pesticides.
Approach; Our laboratory has designed an experimental system to study the interactions between a Gram-
positive biological control organism, a plant host, and a pathogen, which uses recombinant inbred lines of
tomato, Bacillus cereus UW85, and the plant pathogen, Pythium torulosum Coker and Paterson. In my
studies, I have chosen to use tomato seed exudate as the source of plant compounds because the seed and
seedling are most susceptible to infection by Pythium during seed germination and radicle formation. To
identify DNA sequences of B. cereus UW85 that contain promoters or promoter-like sequences regulated
in the presence of tomato seed exudate, I have constructed a promoter-trap plasmid for use in B. cereus,
pAD123. pAD123 contains a promoterless gene that encodes a mutant version of the green fluorescent
protein, GFPmutSa, that is optimized for fluorescence-activated cell sorting or FACS. I have constructed
a library in pAD 123, which consists of 34,000 clones containing 1 -3 kb chromosomal DNA fragments from
UW85. By adapting a cell-sorting protocol for use with B. cereus, it is possible to rapidly screen the library
for regulation of GFP expression when the clones are exposed to compounds originating from a plant host,
tomato. Clones isolated in the screening procedure will be further characterized through sequencing of the
DNA inserts and determination of the biological function of regulated genes in the plant-microbe interaction.
Status: I screened the library using tomato seed exudates, and identified two clones that are up-regulated
in the presence of tomato seed exudate. The clones are currently being characterized.
Papers & Publications; Dunn, A.K., and Handelsman, J. 1999. A vector for promoter trapping in Bacillus
cereus. Gene 226, 297-305.
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U915657
USING CONSERVATION ENDOCRINOLOGY TO ASSESS THE RISK
OF LOCAL EXTINCTION: A CASE STUDY OF MALAGASY LEMURS
Debra L. Durham
University of California, Davis
Objectives/Hypotheses; The aim of my current research is to elucidate the impact of habitat alteration on
female reproductive endocrinology and its implications for the risk of local extinction in mammal
populations. If the females of one species reproduce less effectively than the females of another species
when both are faced with habitat change, differences in reproductive endocrinology could be important
factors contributing to variations in risk of local extinction.
Rationale: The biology of extinction is still poorly understood despite its significance to the preservation
of endangered species. We know that small populations are likely to go extinct, but little is known of the
biological processes that cause decline (Caughley, 1994). We are only beginning to investigate the biology
of differences between taxa in their sensitivity to habitat alteration and how such differences could affect
the risk of local extinction (Harcourt, 1998). While there is some evidence of socioecological correlates to
the risk of local extinction (e.g., Johns and Skorupa, 1987; Struhsaker, 1997; Harcourt, 1998), the physio-
logical bases for risk are largely unknown.
Approach; To determine if there are consequences for risk of local extinction by virtue of species'
differences in the sensitivity of reproductive cycles to habitat disturbance, I will test whether the degree of
habitat alteration is correlated with hormonal measures of reproductive performance in one high-risk and
one low-risk lemur species at Ranomafana National Park, Madagascar, To relate ecological characteristics
of disturbed habitats to differences in reproductive endocrinology that may exist between high- and low-risk
lemur species, a cross-disciplinary approach that draws upon endocrinology, animal behavior and ecology,
and includes both field and laboratory components will be used. Laboratory techniques that have been
modified for use in the field make it possible to collect data about the association between sensitivity to
habitat disturbance and attributes of the female reproductive cycle. These measures, combined with
ecological and behavioral analyses, will contribute to the study of the impact of habitat alteration on female
reproductive endocrinology and its implications for the risk of local extinction.
Status; The pilot project was completed in October 1999. Laboratory validation of enzyme immunoassays
of estrogen and progesterone metabolites were completed in February 2000. Preliminary behavioral data
analysis suggests thatEulemur rubriventer females have higher reproductive performance, as measured by
ovarian function and birth rate, as compared to Eulemur fulvus rufus females.
Papers & Publications; None at this time.
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U915645
ENVIRONMENTAL DECAY OF PATHOGENS
John H. Easton
University of Alabama, Birmingham
Objectives/Hypotheses: The purpose of this research was to develop input parameters for modeling fate
and transport of pathogenic microorganisms to assess the health risks of sewage contamination, especially
from separate sewer overflows (SSOs).
Rationale; Pathogenic organisms found in sanitary sewage can adversely impact human health when
sewage is discharged to waters that humans come in contact with. Fate and transport computer models
require information regarding the environmental decay characteristics of the microorganisms to be sim-
u/ated. Laboratory and field studies were conducted to quantify these characteristics. Previously, this
information has been unavailable for the pathogens in this study.
Approach: The research goal was accomplished in four phases. In Phase I, test organisms were selected.
In Phase II, an evaluation of existing methods to enumerate these pathogens was conducted. Phase HI
consisted of an evaluation of appropriate existing computer models to determine the types of input data
required. And Phase IV entailed conducting laboratory and field studies to generate typical model input
parameters for fate and transport simulation. The research organisms selected were total coliforms,
Escherichia coii, and Enterococci (bacterial indicators); Escherichia coli 0157:H7 (bacterial pathogen); and
Cryptosporidium parvum and Giardia lamblia (protozoan pathogens). These organisms were selected for
the following attributes: they are increasingly a public health concern,, laboratory protocols for their
enumeration exist, and/or they are of historical significance—allowing comparison to previous studies.
Status; These methods have been applied to the organisms of interest and the fate and transport charac-
terization is complete. Future plans entail conducting a risk assessment using a numerical mode! based on
this characterization.
Papers & Publications: Velz, C.J. 1984. Applied stream sanitation. John Wiley and Sons, Inc.
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U915589
THE APPLICATION OF GEOPHYSICAL INVESTIGATIONS TO URBAN LANDFORMSt
A GEOPHYSICAL INVESTIGATION OF THE GEOLOGIC SETTING
OF HILLVIEW ROAD LANDFILL IN DANBY, NY
Alissa M. Ede
Cornell University
Obiectives/Hvpotheses; This project combines two different objectives: 1) to investigate the geologic
setting of a landfill known to be leaking a contaminant (the leachate plume has not yet been contained); and
2) to compare the application of different geophysical techniques to delineate the subsurface in glaciated
terrain.
Rationale; Hillview Road Landfill is located in a unique geologic setting. It is situated in a wetland area
at the junction of two valleys (one large glacial valley and one river valley). It is also at the site of a local
continental drainage divide. The geologic setting is complex. The landfill has been capped for several years
and has been monitored for contaminant leakage. There is at least one well where landfill leachate has been
identified outside of the capped landfill. As a result of the complex geologic setting, however, the extent
of the leachate plume has not been identified, despite several drilled wells in the expected locations.
Geophysical techniques, such as seismic refraction, seismic reflection, ground penetrating radar, gravity
modeling and resistivity, are useful techniques to delineate the subsurface. These techniques are less
invasive and can help cut costs in order to determine where best to drill a well. Limited research has been
done to determine how effective each of these methods are in glaciated terrain.
Approach; Data has been collected using each of the geophysical methods (seismic refraction, seismic
reflection, electrical resistivity, ground penetrating radar and gravity) in the vicinity of the landfill. Site
visits have included investigation of the local geologic terrain. A review of the literature on the local
geologic history and the previous engineering investigation has informed the design of the surveys. Data
from existing wells and from geophysical investigations in the same glacial valley (with less complication)
will also be used in the analysis of the various geophysical techniques and in understanding the geologic
setting of the landfill.
Status; Data has been collected and is in the process of being analyzed.
Papers & Publications; None at this time.
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U915159
THE INFLUENCE OF MEMBRANE TREATMENT ON BACTERIAL
REGROWTH POTENTIAL IN DRINKING WATER
Isabel C. Escobar
University of Central Florida
Obiectives/Hvpotheses: The impacts of membrane treatment on Assimilable Organic Carbon or
Biodegradable Dissolved Organic Carbon levels in drinking water pipe networks in full-scale distribution
systems has had little investigation. The main objective of this project is to collect and analyze full-scale
distribution system data to quantify its response to the introduction of membrane treatment, which affects
the AOC and BDOC of the drinking water, with respect to its impact on bacterial regrowth potential in the
systems.
Rationale: Organic matter impacts the water quality of distribution systems by generating color, undesired
taste, and odors. When a chlorine residual is provided for disinfection, organic compounds are responsible
for high chlorine demands and the formation of disinfection by-products. Also, the biodegradable organic
matter that is not removed during drinking water treatment can lead to the proliferation of bacteria along the
distribution system, which deteriorates the water quality, accelerates corrosion rates of pipes, and can
potentially increase the incident of bacteriological diseases. A treatment process that can remove the majority
of pathogens, water pollutants, and organic carbon is membrane filtration. Some types of membranes may
remove a large portion of the organic material present in the water. This presumably translates into a
corresponding reduction in both disinfection by-productformationpotentialand bacterial regrowth potential.
However, little is known about the effect of membrane treatment processes with respect to changes in
Assimilable Organic Carbon (AOC) or Biodegradable Dissolved Organic Carbon (BDOC) concentrations
for finished water. Since these are the parameters normally used to quantify regrowth potential, the actual
effect of membrane systems on regrowth potential needs further evaluation to generate a quantitative
assessment.
Approach; Two water treatment plants, Palm Beach County Water Utilities Department's WTP #3 and #9,
treat the same raw water source via membrane filtration and lime softening, respectively. These two plants
were monitored monthly for one year to compare the effects of membrane filtration on distribution water
biostability. Samples taken from the distribution systems were analyzed for AOC using Pseudomonas
flourescens PI7 and SpirillumNOX, BDOC, UV absorbance at 254 nrn, temperature, residual disinfectant,
pH, turbidity, heterotrophic plate counts, and coliform counts.
Status; The results of these experiments were that nanofiltration produced a considerable gain in potable
water quality by decreasing bacterial counts and concentrations of organic matter, resulting in more efficient
post-disinfection, maintenance of chlorine residuals, and decreasingthe THM formation potential. However,
the study also determined that nanofiltration membranes might let through a low but significant con-
centration of biodegradable organic matter that is easily assimilable by bacteria (i.e., AOC).
Papers & Publications; Escobar, I. and Randall, A. 2000. Sample storage impact on the assimilable organic
carbon (AOC) bioassay. Water Research 34(5): 1680-1686.
Escobar, I. and Randall, A. 1999. Influence of nanofiltration on distribution system biostability. Journal American
Water Works Association 91(6):76-89 (June 1999).
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U915384
THE EFFECTS OF HUMAN HUNTING ON NORTHERN FUR SEAL (CALLORHINUS
URSINUS) MIGRATION AND BREEDING DISTRIBUTIONS IN THE HOLOCENE
Michael E tinier
University of Washington
Objectives/Hypotheses: My research has two main goals. The first is to determine whether or not there is
any archaeological evidence of northern fur seals (CaUorh'mtis ursinus) breeding between Oregon and
Alaska. The second goal will be to determine what role, if any, human hunting pressure may have played
in structuring the modern breeding distribution of fur seals, which is presently limited to the central Bering
Sea and southern California. Due to limitations of the archaeological record, my study will focus on the past
2000 years.
Rationale; Prior to the late 1960s, wildlife biologists believed that the breeding behavior of fur seals had
been relatively constant throughout the Holocene—that is, breeding rookeries have been confined to remote
islands in the extreme North Pacific and the Bering Sea for the past 10,000 years or so. However, the recent
establishment of a rookery off the coast of southern California, coupled with archaeological evidence of
extinct rookeries in California and Oregon, suggests that at one time fur seals had a much more extensive
breeding distribution, possibly extending the entire west coast of North America. Other species of pinnipeds
have shown similar distributional changes, probably as a result of population growth following the cessation
of commercial sealing in the early 1900s. Northern fur seals differ from this general pattern in that, while
their breeding distribution has been expanding over the past several decades, their numbers have steadily
declined. While it is likely that the breeding distributions of many pinniped taxa are changing in response
to cessation of hunting pressure, archaeological evidence from California and Oregon suggest that northern
fur seals may have been significantly affected by prehistoric hunting pressure.
Approach: To conduct my research, fur seal skeletal material from selected archaeological sites along the
coasts of Washington, British Columbia, and southwest Alaska is being analyzed. This poster represents
preliminary results from several of these sites. Age and sex profiles have been constructed based on
comparison of the archaeological material with skeletons from known-age individuals. Of particular interest
is the presence/absence of juveniles younger than 4 months. Prior to 4 months of age, fur seal pups are too
weak to swim considerable distances. Thus, the presence of individuals in this age class would suggest that
people living in the area were utilizing a nearby rookery. In contrast, the absence of pups younger than 4
months would be consistent with the hypothesis that the only seals being utilized were those that were
migrating from distant breeding grounds. Any apparent changes in the breeding distribution of fur seals
within the time period covered will be cross-referenced with published information on variability in climate,
oceanography, and sea levels over the same time period. These parameters are known to have varied con-
siderably over the past several thousand years. Furthermore, the unique life history of fur seals would make
breeding populations particularly susceptible to these sorts of changes. The role of human hunting can only
be considered after these environmental factors have been ruled out.
Status; Thus far, I have analyzed five archaeological assemblages from Umnak Island and Kodiak Island,
Alaska. I am presently working at the Makah Museum in Neah Bay, Washington, analyzing the fur seal
component from the Ozette excavations. In addition to having nearly perfect preservation of all organic
remains (even fragile basketry and woven hair), this 2,000 year old site is also notable fertile extremely large
sample of fur seal bone. I am in the process of sorting through the 64,000 pieces of identified mammal bone
to focus on a sub-sample of mandibles and teeth, which will represent somewhere around 1,500 individual
seals.
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Papers <& Publications: Etinier, M. 2000. Inventory of skeletal measurements of known-age northern fur
seals (Callorhinus ursinus). http://students.washington.edu/~metnier/measure.htm
Etinier, M. 2000. Demographic analysis of archaeological fur seal (Callorhinus ursinus) assemblages from
the eastern North Pacific. Paper presented at the 27th Meeting of the Alaska Anthropological Association,
Anchorage, AK.
Etinier, M. 2000. Characteristics useful in distinguishing male and female fur seals (Callorhinus ursinus)
from skeletal material. Alaska Consortium of Zooarchaeologists Workshop on Seal Bone Identifications, in
conjunction with the 27th Meeting of the Alaska Anthropological Association, Anchorage, AK.
Etinier, M. 1999. Modeling patch choice, patch breadth, and patch residence time in archaeological dietary
studies. Paper presented at the 64th Annual Meeting of the Society for American Archaeology, Chicago, IL.
Etinier, M. 1998. Using archaeological data to explain pinniped biogeography in the eastern North Pacific.
Environmental Studies Seminar Series, Western Washington University, Bellingham, WA.
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U915637
SELECTED ASPECTS OF THE TOXICOKINETICS AND BIOAVAILABILITY
OF CADMIUM AND LEAD IN ANIMAL AND CELLULAR MODELS
Timothy J. Evans
University of Missouri, Columbia
Objectives/Hypotheses; The objectives of this research are to fill in data gaps regarding the subacute
toxicokinetics and relative bioavailability of cadmium (Cd), following oral exposure in an animal model,
and to study factors that affect trophoblastic uptake of divalent lead [Pb(II)] in an in vitro model. It is
hypothesized that Cd blood levels can be measured in orally exposed, juvenile swine and that Cd
toxicokinetics in this species are associated with tissue metallothionein (MT) levels, as proposed in rodent
species and cellular models. Another hypothesis relating to Cd is that assessment of MT induction in various
tissues may be useful in estimating the relative bioavailability of Cd in a soil matrix. With regards to Pb(II),
it has previously been proposed that Pb(II) competes with divalent calcium [Ca(II)J for cellular uptake, and
this hypothesis will be evaluated with respect to trophoblastic cells.
Rationale; Cd is a common environmental contaminant with multiple, adverse effects on human health.
The fetus is very susceptible to the effects of Pb toxicosis, and trophoblastic cells are involved in the transfer
of nutrients and potential toxicants to the fetal circulation.
Approach; Male, juvenile swine will be orally dosed with varying doses of Cd as cadmium chloride or in
a soil matrix, for up to 2 weeks. On selected days of each study, blood samples will be taken prior to dosing
and at hourly intervals after the oral administration of Cd. At the end of each experiment, the pigs will be
sacrificed, and tissues collected for analysis. Blood and tissue Cd concentrations and tissue levels of MT
will be determined for the different Cd doses. The data will be analyzed in order to make inferences
regarding the subacute toxicokinetics of Cd and the possible role of MT in the disposition of Cd. Based on
the resulting data, attempts will be made to develop additional techniques of estimating the relative
bioavailability of Cd in soil matrices. Undifferentiated and differentiated Rcho-1 cells will be grown in
culture, harvested, and incubated with the acetoxymethyl ester of indo-1. Indo-1 fluorescence in these cells
will be measured after the addition of varying amounts of Pb(II), in the presence or relative absence of
extracellular Ca(II), and following the depletion of intracellular Ca(II) stores by thapsigargin. Future
experiments will investigate the effects of a variety of factors on indo-1 fluorescence quench in these and
other trophoblastic cells.
Status; Preliminary experiments have been completed, which tentatively support the initial hypotheses and
expectations. Upcoming experiments should be completed in the next 6 to 12 months.
Papers & Publications; None at this time.
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13915227
DETECTION OF NITRIC OXIDE IN MICE
BY ELECTRON PARAMAGNETIC RESONANCE TECHNIQUES
Jesse A. Fecker
Dartmouth College
Objectives/Hypotheses; The objective of this research is to study the chemical and biological properties
of dithiocarbamate compounds. Specifically, iron(II)-dithiocarbamate complexes are used to determine
nitric oxide levels by electron paramagnetic resonance (EPR). The ability to detect and quantify nitric oxide
levels will lead to an improved understanding of the role nitric oxide plays in pathophysiology.
Rationale; Altered synthesis or metaboiism of nitric oxide, causing a change in nitric oxide levels, may
produce a pathophysiological response. Therefore, it is desirable to accurately measure the concentration
of nitric oxide in an organism. This is a difficult task, due to the short lifetime, unusual chemistry, and low
concentration of nitric oxide in animals. Nitric oxide can be "trapped" by iron(II)-dithiocarbamate
complexes, rendering it detectable by EPR. At present, the method using iron(II)-dithiocarbamates gives
a rough measure of how much nitric oxide is present in cells, mice, and rats. The work described below will
make a more precise quantification of nitric oxide possible. In addition, the project explores how this
technique may eventually be modified for human use.
Approach; The project began with a study of dithiocarbamate use in assessing nitric oxide levels in mice.
Based on the results of the initial study, three areas of investigation were identified. The first project aim
is to determine the metal binding properties of various dithiocarbamates by EPR spectroscopy, UV-vis
spectroscopy, and/or isothermal titration calorimetry. The second aim is to assess nitric oxide binding
efficiency to several iron(II)-dithiocarbamate complexes by EPR spectroscopy. The third aim involves the
synthesis of novel dithiocarbamates from commercially available amines and carbon disulfide; the novel
compounds can be adsorbed onto or tethered to a solid matrix. The metal and nitric oxide binding properties
of the novel dithiocarbamates will be tested as described above.
Status: There is approximately one year remaining until this project is completed. As of April 2000, the
research is focused on obtaining the metal binding constants of Cu(ll), Fe(II), Fe(III), and Zn(II) to several
dithiocarbamates. In addition, the novel dithiocarbamates have been synthesized and await testing.
Papers & Publications: None at this time.
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U915577
BARRIERS TO FOREST REGENERATION ON
ABANDONED CENTRAL AMAZONIAN PASTURES
Ted R. Feldpausch
Cornell University
Objectives/Hypotheses; To investigate revegetation dynamics as a function of biophysical variables
across a regenerating successional gradient of abandoned pasture to forest. Questions to be answered
include: 1) How do biophysical conditions impact germination rates and seedling growth/survival? 2) How
do agro-forestry and common native successional species respond to changing environmental conditions?
3) How do biophysical conditions vary with succession and how do these conditions inhibit or accelerate
forest fallow succession?
Rationale; Conversion of the Amazon Basin to pasture has received much attention over the past decade
and there is concern that intensely used pasture may remain as degraded scrub forest after abandonment.
Increased production longevity and rehabilitation of degraded lands is needed to reduce pressure to clear
additional lands. This improved land management is imperative, as there are an estimated 20-35 million
hectares of abandoned pastures in the Amazon, much in advanced stages of degradation with low
regeneration rates, carbon sequestration and biodiversity. Results of this study will advance the under-
standing of ecological barriers of forest regeneration and produce management techniques for enhanced
forest reestablishment on abandoned land in the central Amazon.
Approach; Two important considerations in woody species invasion of pastures and the development of
forest fallows are whether species can be established and how growth proceeds. I will test the revegetation
dynamics of fallow vegetation under four successional pasture chronosequences in a converted rainforest
located in the central Amazon near Manaus, Brazil. Successional treatments include: 1) grass dominated
pasture, 2) grasses and woody shrubs, 3) shade intolerant open canopy woodlot, and 4) late successional
forest. Under these four chronosequence treatments I will: 1) determine the germinability of desirable and
undesirable forest fallow species, 2) test revegetation dynamics (e.g., LAI, survival, net assimilation rate)
of planted agroforestry and natural successional species, and 3) assess above and below ground biophysical
dynamics of the four treatments over time. The species introduction tests will be divided into two
components, germinability and transplanted species tests. To better understand germination success, several
common early and late successional woody species will be planted and germination will be recorded across
the four treatments. Two species of woody agroforestry seedling species and two species of woody native
indigenous successional species will be transplanted into the four treatments and growth monitored over time
to better understand fallow succession. Potential agroforestry tree species are Cupuacu (Theobroma
grandiflorum) and Teca (Tectona grandis) because of their high economic value and Cecropia spp. and
another indigenous, late successional species. Soil water flux will be monitored with a Trime TDR probe.
Vegetation water potential will be measured over time to determine water uptake and stress using the
pressure bomb technique. A CID, Inc., CI-110 canopy analyzer will be used to assess leaf area, canopy
architecture, and solar radiation interception. The experiment terminates with destructively harvesting
vegetation on the preceding treatments for leaf area, net assimilation, carbon sequestration, soil and total site
nutrient stock analysis.
Status; I will travel to the field site in May 2000 to evaluate and select treatment plots, run common garden
preliminary seed germination tests and begin seedling production for transplant into treatments. During the
dry season, I will characterize the field plots; field tests and biophysical data collection across all treatments
will commence in October with the rainy season.
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Papers & Publications; Feldpausch, T.R. and Downs, J.L. Evaluation of sagebrush revegetation four years
after planting into a post-fire shrub-steppe community, (prepared for submission)
Feldpausch, T.R. 1996. Effects of grazing on the vegetative community cover of the paloverde marsh. In:
Tropical Conservation Biology 96-11. Organization for Tropical Studies. Duke University. 235p.
Feldpausch, T.R. 1996. Agroforestry as an Alternative land use option for the sustainable future of Costa
Rican farmers. In: Tropical Conservation Biology 96-11. Organization for Tropical Studies. Duke Univer-
sity. 235p.
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U915373
ANALYSIS AND FATE OF SEWAGE-DERIVED POLAR CONTAMINANTS
IN THE MARINE ENVIRONMENT
Patrick L. Ferguson
State University of New York, Stony Brook
Objectives/Hvpothcses: The objectives of the current work are to: I) develop sensitive and selective
analytical methods for determining toxic and estrogenic sewage-derived organic contaminants in the marine
environment, and to then 2) use the developed methods to conduct a comprehensive study of the fate and
distribution of these compounds in impacted environments.
Rationale: The input of treated and untreated sewage to aquatic systems represents a significant source of
anthropogenic contaminants to the environment. Many of the chemical constituents of sewage effluent have
been found to act alone or in combination as toxins or as environmental endocrine disrupters. It is, therefore,
imperative that studies of the environmental fate and distribution of these compounds be carried out in order
to assess the environmental risk from this source of aquatic pollution. The contaminants of interest include
surfactants, such as the estrogenic nonylphenol ethoxylates (NPEOs) and the toxic quaternary alkyl-
ammonium salts (such as DTDMAC), as well as natural and synthetic hormones such as estradiol (E2),
estrone(El),andethyny]estradiol(EE2). Studies of these polar compounds in the natural environment have,
in the past, been hampered by the lack of reliable and sensitive analytical methods for their determination.
With the recent advent of electrospray mass spectrometry, such methods have become available, although
considerable method development is often required before reliable results can be obtained.
Approach: High performance liquid chromalography-electrospray mass spectrometry (HPLC-ES1-MS)
methods will be developed for the determination of the three classes of contaminants to be studied: NPEOs,
quaternary ammonium surfactants (DTDMAC), and steroid hormones (El, E2, EE2). Full method
development will include optimization of extraction and cleanup techniques, determination of chroma-
tographic conditions, and exploration of matrix effects on signal response in the electrospray process. The
developed methods will be used to study the fate of specified analytes in a sewage impacted, urban estuary.
Specifically, levels of contaminants will be quantified in surface sediments, dated sediment cores, sewage
effluent, suspended particles, and surface waters. From this survey, sources and sinks will be quantified, and
the distribution and behavior of the pollutants within the estuary will be determined spatially and temporally.
Status; Analytical methods have been completely developed and tested for NPEOs, The resulting technique
has been used to perform a comprehensive fate and distribution study on NPEOs in an urban estuarine
environment. Work has begun on a new method for analyzing steroid hormones in sewage effluent and
marine waters by HPLC-ESI-MS. Future work will include examination of steroid hormone concentrations
in sewage effluent and receiving waters, analysis of quaternary ammonium surfactants in estuarine
sediments, and profiling of NPEOs in a dated sediment core.
Papers & Publications; Ferguson, P.L., Iden, C.R., and Brownawell, B.J. 2000. Analysis of alkylphenol
ethoxylate metabolites in the aquatic environment using liquid chromatography-electrospray mass
spectrometry. Analytical Chemistry (submitted)
Ferguson, P.L. and Brownawell, BJ. 2000. Fate and distribution of alkylphenol ethoxylate metabolites in
a sewage-impacted urban estuary, (manuscript in preparation)
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U915603
ENVIRONMENTAL ENFORCEMENT CHOICE: TRADING OFF EQUITY
FOR ENVIRONMENTAL BENEFITS
Jeremy M. Firestone
University of North Carolina, Chapel Hill
Objectives/Hypotheses; Although there are procedural and substantive differences between civil and
criminal liability, EPA has broad discretion to choose among administrative, civil judicial, and criminal
venues when it elects to penalize violators. EPA thus plays an important gatekeeper function: it rations its
own scarce personnel and fiscal resources as well as access to other institutions such as the Department of
Justice, U.S. Attorneys Offices, and federal courts. When it chooses, EPA does so with a preference to
resolve a violation civilly rather than criminally, because with civil actions EPA can more easily meet its
burden of proof and build on existing precedents. EPA prefers administrative to judicial actions because
judicial proceedings require greater resources, provide targets with an enhanced ability to influence the
outcome, and are characterized by delay and loss of EPA control. These preferences lead EPA to. punish
approximately 70% of violators administratively, 20% civil judicially, and the remainder criminally. This
leads to the question: What influences EPA's choice among the three fora?
Rationale; This study makes an important contribution to the body of literature on environmental en-
forcement in four ways: I focus on the choice among enforcement fora; look at enforcement across
environmental media; consider environmental enforcement broadly rather than confining my research to a
particular industry or firm size; and examine the treatment of individuals and governments in addition to
firms. This study should generate suggestions on how EPA can more equitably and effectively bring to bear
its finite enforcement resources, deter violations, and enhance environmental protection.
Approach; I assembled a database of more than 300 administrative, civil judicial, and criminal actions that
were initiated during fiscal years 1990-1997 under the air, water, and hazardous waste programs. Each case
is itself a cluster of violators. I construct empirical models (adjusted for stratification and cluster sampling)
to analyze the choice among administrative, civil judicial, and criminal actions. I separately model EPA's
"individual" and "organizational" violator decisions. I model EPA as both an environmental harm minimizer
and as a political support maximizer. I also examine whether environmental penalty provisions and the
enforcement programs are structured in a manner that results in equitable treatment of violators.
Status: I will defend my dissertation late spring or early summer.
Papers & Publications; None at this time.
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U915482
NITROGEN REMOVAL IN CONSTRUCTED WETLANDS: ENHANCEMENT
OF NITRATE MASS TRANSFER IN THE DENITRIFICATION ZONE
Maia S. Fleming
University of California
Objectives/Hypotheses: The objective of this research is to explore three hypotheses regarding control and
enhancement of denitrification rates in constructed wetlands designed for nitrogen removal. The central
hypothesis is the following: 1) denitrification in constructed wetlands follows first order kinetics with respect
to nitrate. Two related hypotheses are also proposed, which expand upon the central hypothesis. 2) deni-
trification rates can be enhanced by increasing mass transfer of nitrate from the bulk water to the denitrification
zone; and 3) promotion of a denitrifying episediment zone will enhance denitrification rates above those found
in purely sediment-based denitrification zones.
Rationale; Over the past two decades, wetlands have been recognized for their inherent capability to act as
nitrogen sinks through the processes of denitrification, sedimentation, and plant uptake of nitrogen.
Constructed wetlands have been increasingly designed for nitrogen removal and have been shown to remove
nitrate, mainly through denitrification, at rates of 200 to 5,000 mg N/m2/d. These reported rates are 1 -3 orders
of magnitude greater than denitrification rates in natural lake, estuarine, and wetland sediments. Despite this,
average reported nitrate removal efficiencies for constructed wetlands range broadly, from 30 to 95%. Removal
efficiencies in the >90% range are preferable, and in many cases essential, to offset high land costs and
potential evaporative water loss in arid climates. Optimization of denitrification reliability and efficiency will
help to ensure that constructed wetlands are an economically feasible treatment technology.
Approach: Laboratory bench-scale wetland microcosms and field-scale mesocosms are used to measure
denitrification rates and nitrate mass transfer under four experimental conditions. Two of the experimental
conditions will focus on a sediment-based denitrification zone. In these experiments, a clearly defined
sediment-water interface will be promoted to test the extent of nitrate mass transfer from the overlying water
into the sediments for denitrification. The efficacy of an episediment denitrification zone will be tested under
the two remaining experimental conditions, using a constructed thatch of cattail leaves and stems positioned
at the sediment-water interface. The laboratory microcosms are flow-through, temperature controlled (20C),
anoxic (N2 sparged), and include sediments, water column, and a headspace. Nitrate levels in the microcosm
influent will be manipulated within the 1-100 mg/L range, based on realistic constructed wetland
concentrations. Steady state effluent nitrate concentrations will be measured using ion chromatography, and
denitrification rates will be calculated by nitrate mass balance. In order to determine the location and extent
of the denitrification zone, water column and sediment vertical profiles of nitrate and chloride (a conservative
species) will also be measured at steady state using a thin-film polyacrylamide gel sampler. Multi-way
ANO VA wi] 1 be used to evaluate statisti cal differences between treatments, whi le linear regression and/or curve
fitting will be used to determine the appropriate relationship between denitrification rate and nitrate
concentration within treatments.
Status: Significant differences (pO.Ol) in the rate of nitrate removal between episediment and sediment
treatments have been measured at a 35 mg-N/L nitrate condition and three residence times (2, 5, and 10 days).
Reaction order differences between treatments have not yet been determined as the microcosms have been
operated at one nitrate condition to date. The field-scale mesocosms have been planted and are reaching their
first full growth season. Field sampling is expected to commence May 2000.
Papers & Publications: None at this time.
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U915606
PROXIMAL AND DISTAL FACTORS IN DESERT ANNUAL SEED GERMINATION
C.J. Fotheringham
University of California, Los Angeles
Objectives/Hypotheses: I am interested in how plant communities in harsh environments respond to
multiple stresses and have evolved mechanisms to capitalize on semi-predictable 'extreme events' that
radically alter environmental parameters. Here semi-predictable refers to an event that will occur within a
given time frame, but is unpredictable as to when it will occur within that time frame. Frequent recurring
wildfires in California chaparral ecosystems are a good example. The model I use for this research is the
evolution of deep seed dormancy in annual plants and the corresponding environmental cue that triggers
germination. Studies conducted in the past show that post-fire chaparral annuals are stimulated to germinate
by trace gases in smoke. Fire, which removes all above-ground btomass, is the 'extreme event' and the
germination cue is trace gases or nitrogen oxides that are present in smoke, but are rare or absent under
normal conditions. Desert and chaparral annual species share a close phylogenetic relationship. Post-fire
chaparral annuals also have desert populations or desert sibling species. In the desert, these species are
restricted to high organic content soils under shrub canopies (nutrient islands). Recent studies that I have
conducted show a majority of these desert annuals exhibit deep dormancy and a similar smoke germination
response (indicative of a trace gas or nitrogen oxide cue) as observed in chaparral seeds. If the selection for
this trait is due to an extreme event, it is unlikely to be fire, which is historically absent from desert
communities. In my current research, I hypothesize the selection mechanism is most 1 ikely heavy rains, such
as those that occur in El Nifio years.
Rationale: Regardless of the mechanism behind selection of this germination response, reliance on a
nitrogen oxide or trace gas germination cue puts these species at risk due to the current high levels of
anthropogenicatly produced nitrogen deposition and trace gases. Recent introduction of fire into the desert
compounds the situation. In annual species, seeds are the only link from one generation to the next, and
production of a dormancy-breaking cue at inappropriate times by anthropogenic sources will cause seeds to
germinate under unsuitable conditions and result in extinctions. The possibility of germination being cued
by microbial processes in the desert is also problematic, Microbial processes are very sensitive to pH and
temperature fluctuations. Increases in global temperature due to the "Greenhouse effect" and decreases in
rain water pH due to sulfur dioxide and other industrial emissions (acid rain) could both have unforseen
effects. Annual plants in arid and semi-arid ecosystems act as important, readily digestible food sources for
native fauna. Loss of annual plants could have a domino effect of environmental degradation and species'
extinctions. To understand what management steps should be taken to prevent this loss, further studies are
needed to determine what is the natural germination cue, how it is produced in nature, and what mechanism
is involved. Only then can we design models that predict how seed germination is being affected (or will
be affected) by anthropogen ic impacts such as fires in the desert and increasing nitrogen deposition and trace
gases.
Approach: This research addresses two hypotheses: 1) Desert annuals, like post-fire chaparral annuals,
germinate in response to nitrogen oxides. To test this hypothesis, I will conduct germination trials based on
known dormancy-breaking cues of closely related chaparral species and the results of studies on soil
chemistry. 2) Nitrogen oxides are produced naturally by soil microbial processes only under very specific
conditions of water saturation, temperature, and organic content of the soil. To test this hypothesis, I will
conduct studies on native desert soils under variable water saturation levels, temperatures, and organic
content. These studies will use standard tests to understand the effect of these variables on microbial activity
and soil chemistry including: nitrite/nitrate accumulation, trace gas efflux, and changes in pH.
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Status: Work in progress.
Papers & Publications; Keeley, J.E. and Fotheringham, C.J. 1998. Mechanisms of smoke-induced ger-
mination in a post-fire chaparral annual. J Ecol 86:27-36.
Keeley, J.E. and Fotheringham, C.J. 1998. Smoke-induced seed germination in Californian chaparral. Ecol
79:2320-2336.
Keeley, J.E. and Fotheringham, C.J. 1997. Trace gas emissions and smoke-induced seed germination. Sci
276:1248-51.
Keeley, J.E. and Fotheringham, C.J. Role of fire in regeneration from seed. In: M. Fenner, ed. Seeds: the
ecology of regeneration. CAB International, Oxon, UK. (in review)
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STAR Graduate Fellowship Conference
U915329
IMAGE USE IN THE CHARACTERIZATION OF FIELD PARAMETERS:
INTEGRATION OF REMOTE SENSING WITH HYDROLOGIC SIMULATION MODELING
Garey A. Fox
Texas A&M University
Objectives/Hypotheses: The primary focus of this research involves investigating the development of an
integrated system using remote sensing and hydrologic simulation modeling for the purpose of improving
model simulation of production, hydrologic, and environmental sensitivities of watersheds. The research
focuses on obtaining field data and geo-referenced multi-temporal images throughout growing seasons of
cornfields. An automated procedure to radiometrically calibrate multi-temporal images to correct for sensor
degradation and changes in scene and atmospheric conditions will be developed. Detailed measurements
of influential soil and vegetation properties from the aerial images will be obtained, and procedures will be
developed for integrating these within-field measurements into the hydrologic simulation model.
Rationale; Even though proven to be valuable tools in precision farming individually, no widely accepted
procedure exists that incorporates remote sensing and hydrologic simulation modeling. Such a system could
simultaneously improve calibration and accuracy of hydrologic simulation models in the prediction of crop,
hydrologic, and environmental sensitivities within fields.
Approach; The first step in this research requires obtaining field data and geo-referenced multi-temporal
images throughout growing seasons of Midwestern cornfields. In an attempt to radiometrically correct these
images, this research will lead to the development of an automated procedure to radiometrically calibrate
the multi-temporal images to correct for sensor degradation and changes in scene and atmosphere conditions.
Then, the hydrologic simulation model will be used to simulate the growth of the crop throughout the
growing season prior to model calibration. From these simulations, influential soil and crop parameters and
important production and environmental outputs will be identified. The next step will then focus on obtaining
detailed measurements of these influential soil and vegetation properties from the aerial images, and
comparing these derived values to ground measurements at several control points. Finally, the research will
include the development of procedures for integrating within-field measurements obtained from aerial
images into the hydrologic simulation model. Once incorporated, the research will attempt to evaluate
differences between model simulations with and without incorporated remotely sensed measurements.
Status; Most of the research activities have been completed at this time, including the procedures for
incorporating remotely sensed measurements into the hydrologic simulation model. However, further data
analysis still remains in order to determine the usefulness of the procedures for a variety of image and field
conditions.
Papers & Publications; None at this time.
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U915612
MAPS OF THE FUTURE: MULTI-SCALE PRECIPITATION
MODELING AND FORECASTING
Chris C. Funk
University of California, Santa Barbara
Objectives/Hypotheses; To build combined physical and statistical models of precipitation to generate
high resolution forecasts, given global climate model input. These high resolution precipitation fields may
then be used to develop historical time-series on continental scales, anticipate potential drought and flooding
in the upcoming year, or explore the impacts of climate change. We develop models for a region, Africa,
where there is a pressing need for better information, and the effects of extreme events can exert a heavy toll.
Rationale: There are useful and interesting relationships between large scale weather patterns and the
frequency of local rainfall events. By linking higher resolution single column precipitation models with non-
parametric probability models, we can express, utilize, and explore these relationships.
Approach: We begin with a set of daily precipitation values from 1094 weather stations from continental
Africa, and a 33 year times-series of global climate model data (temperature, velocity, specific humidity,
etc.). The global climate model data is used in two ways. First, the precipitation rate is extracted for each
day, for each grid cell situated over Africa. Second, wind velocity, humidity and temperature fields in
conjunction with local topography obtained from a digital elevation model are used to drive a diagnostic
model of orographic precipitation. These two steps result in two estimated precipitation fields: the final step
transforms these fields into a conditional probability distribution.
The distribution of daily rainfall amounts varies widely with location in Africa. Different regions have
different climate dynamics and different distributions of daily rainfall. To account for this spatial
heterogeneity, we develop unique sets of statistical models for each weather station. These logistic
regression models link the global climate and orographic rainfall amounts, to the observed frequency of
rainfall events at a range of intensities. Given climate and orographic rainfall amounts, we are then capable
of building a conditional distribution function, from which we can infer probabilities of given events or the
maximum likelihood estimate of precipitation. The coefficients of these models are interpolated to a
continental grid, and used to derive a historic time-series of daily rainfall.
Status: All requisite data have been collected. Orographic model has been coded in C and run, generating
precipitation fields for 33 years of daily events on a 0.1 degree grid of Africa. Logistic regression models
have been built in Splus, and interpolated to the study grid with Spherekit, a spatial interpolation toolkit.
Daily rainfall estimates need to be generated and analyzed, and the overall technique and implications
evaluated.
Papers & Publications; Verdin, J., Funk, C., Klaver, J., and Roberts, D. 1999. Exploring the correlation
between Southern African NDVI and ENSO sea surface temperatures: results for the 1998 maize growing
season. International Journal of Remote Sensing 20(10):2117-2124.
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U915539
PHYSIOLOGICAL AND BIOCHEMICAL CONTROLS OVER ISOPRENE
EMISSION FROM PLANTS
Jennifer L. Funk
State University of New York, Stony Brook
Objectives/Hypotheses; The goal of this research is to identify physiological and biochemical factors
contributing to variation in the basal rate of isoprene emission from plants.
Rationale; Isoprene emission from plants is one of the principal ways in which plant processes alter
atmospheric chemistry. Environmental and physiological factors controlling the observed variation between
individuals and within ecosystems have not been identified. Understanding the mechanisms contributing
to variation in basal emission rate is important for estimating regional and global levels of isoprene emission,
which can be used in atmospheric chemistry models.
Approach; Changes in plant carbon balance in response to environmental stress or resource availability are
known to occur in many plant species and may result in potentially large fluctuations in basal emission rate.
At the physiological level, I plan to sample populations of species that occur along natural nutrient and
precipitation gradients. I will document patterns of emission along gradients and screen for potential physio-
logical influences on the rate of emission (e.g., photosynthetic capacity, growth rate). At the biochemical
level, I will assess the influence of three metabolic processes, photosynthesis, photorespiration and
respiration, on isoprene flux rate. If these processes significantly influence emission, the change in relative
importance of each process, in response to environmental and physiological pressures, may contribute to the
observed variation between individuals and populations.
Status; Preliminary work examining the effect of starch pools on diurnal patterns of isoprene emission has
been conducted and presented at a Gordon Research Conference this past February. Sites are now being
selected to address physiological controls.
Papers & Publications; Funk, J.L., Jones, C.G., and Lerdau, M.T. 1999. Defoliation effects on isoprene
emission from Populus deltoides. Oecologia 118:333-339.
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U915585
TOXICITY STUDIES OF CHLORPYRIFOS TO LEOPARD
FROG (RANA PIPIENS) EMBRYOS
Lia M. Gaizick
University of Maryland, Eastern Shore
Objectives/Hypotheses; To determine the effective concentration (EC50) of chlorpyrifos (CPF) to Rana
pipiens embryos. Specific interests include determining the sensitivity of embryonic life stages (Gosner
stages 12-20) ofR. pipiens to CPF. Also, to perform comparative studies using Daphnia magna neonates
and Vibrio flscheri (using the Microtox assay).
Rationale: Within the last 12 years, researchers have been recording significant declines in amphibian
populations and mass incidences of malformations. It is important to research the cause of these obser-
vations since amphibians serve as a connection between aquatic and terrestrial food webs, control insect
populations, and are indicators of developmental toxicants that may impact humans.
CPF, an organophosphate insecticide, is used in large quantities in the United States. It can be applied from
April through July and may enter water bodies when amphibians are breeding. Most amphibians develop
from eggs to free swimming larvae quickly. The residence time of CPF in water is relatively short, so
chances for exposure may come during the embryonic stages. Although embryos do have protection,
provided by a jelly capsule, some chemicals may be able to pass through that barrier. CPF is an
acetylcholinesterase inhibitor and causes neurological/motor function damage in many test species if
exposure occurs during development. This leads to debilitating problems such as susceptibility to predators
and inability to acquire food. Results from this study can be compared with those on other species to
determine any correlation. Results may also aid in determining if exposure to CPF is one of the causes of
frog population declines and malformations.
Approach; Standard acute toxicity tests (96 hrs) were carried out on Rana pipiens embryos in an
environmental chamber. Water temperature remained at 19° C. Effects examined at the conclusion of the
96 hours were hatching time, hatching success, and physical malformations such as edema, skin dis-
coloration and curvation of the tail. Glass finger bowls (105 mm x 44 mm) served as test chambers. Each
bowl had 10 embryos. Test concentrations were 0, 10, 50, 100, and 200 ppb CPF, with tests being run in
triplicate. Dissolved oxygen, temperature, pH, and water hardness were monitored. A 2 mg/L CPF stock
solution was used to make dilutions with reconstitued spring water. No carrier solvent was used in order to
reduce toxic carryover effect from solvent. Chlorpyrifos concentrations were analyzed at the beginning and
end of the 96-hour tests. Daphnia magna static acute toxicity tests of 48 hours were followed according to
procedures outlined in Standard Methods for the Examination of Water and Wastewater. The Microtox assay
was also run, using the organic solvent test protocol.
Status; All testing is completed, and I am finishing my course work this semester. I plan to defend my
thesis during summer 2000.
Papers & Publications; None at this time.
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U915563
LABORATORY STUDIES OF TROPOSPHERIC OZONE FORMATION: A NOVEL
TECHNIQUE FOR PROBING VOLATILE ORGANIC HYDROCARBON OXIDATION
Eva R. Garland
California Institute of Technology
Objectives/Hypotheses; The goal of this research is to design and implement a novel method for directly
probing the primary kinetics and reaction pathways of several alkoxy radicals.
Rationale: Tropospheric ozone, which poses a human health hazard, is formed from a sequence of reactions
involving nitrogen oxides and volatile organic hydrocarbons (VOCs). Alkoxy radicals are critical
intermediates in the oxidation of many VOCs, however, it is experimentally difficult to monitor their various
reaction pathways. One reaction channel is an isomerization through a cyclic transition state, which is
believed to be increasingly important as the length of the hydrocarbon chain increases.
Approach: It will be possible to detect the primary reaction products of the alkoxy radical with a novel
technique called cavity ringdown spectroscopy (CRDS). CRDS provides high sensitivity with a time scale
of a few microseconds. Pulsed radiation is injected into a cavity containing the sample to be studied that is
bordered by two highly reflective mirrors, and the transmitted radiation decays exponentially with a lifetime
determined by the mirror reflectivities and losses due to absorption over the effective pathlength. CRDS
provides for several orders of magnitude more sensitivity than traditional spectroscopic techniques.
Status; The cavity ringdown apparatus has been built and sensitivity tests are currently underway. The
system will be ready for the alkoxy radical isomerization experiments within the next few months.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915573
ORIGINS AND HYBRIDIZATION OF INVASIVE SALTCEDAR (TAMARIX)
INFERRED FROM DNA SEQUENCES
John F. Gaskin
Washington University, St. Louis
Obiectives/Hvpotheses; To determine the specific identity and Eurasian origins of invasive saltcedar
populations, and investigate putative post-introduction hybridization between historically separated species.
Rationale; The second worst plant invasion in the United States consists of 4-8 species from the genus
Tamarix (Tamaricaceae). There is currently little consensus concerning the taxonomy of invasive saltcedar.
These rapacious weeds are displacing native species on over 1,000,000 riparian acres in the southwest, and
the invasion is expanding 3-4% per year. Putative hybridization between morphologically similar naturalized
taxa may have altered the phenorypic characters that trigger host feeding by biological control insects
currently being tested. Invasions of nonindigenous species into natural habitats are now considered the
second largest ecological disaster worldwide. In addition to the $137 billion per year economic cost of
nonindigenous species on our nation's agriculture, forestry, and public health, approximately 400 of the 958
species that are listed by the Endangered Species Act are at risk primarily due to competition with and
predation by nonindigenous species. The histories of invasive species, including their geographic origins,
number and location of introductions, population structure, and detection of genotypes unique to the
introduction, will add critical insight to our knowledge of invasion processes, and can expedite and enhance
searches for extremely host-specific biological control agents.
Approach; This project will be the first application of molecular sequence data and phylogeography for
invasive plant research. Vouchered DNA samples will be used to compare the range of DNA sequences of
the invasive specimens with that of different suspect Old World species, unambiguously elucidating the taxa
or taxon that comprise the invasions. For the phylogenetic analyses, I will sequence the nuclear ribosomal
internal transcribed spacer (ITS) region and a chloroplast transfer RNA gene, which give resolution at the
species level. Parsimony analysis will be used to illuminate interspecific relationships and any putative
hybridization events. Post-naturalization hybrid events will be revealed if an invasive or naturalized
specimen contains a chloroplast sequence belonging exclusively to the native genotype of one species, and
a nuclear sequence belonging exclusively to the native genotype of a different species (phylogenetic
incongruence), or if an invasive or naturalized specimen contains nuclear haplotypes corresponding
exclusively to the native genotypes of two different species (nuclear heterozygosity). To pinpoint invasive
population origins, I will sequence the ppcL locus (the fourth intron of phosphoenolpyruvate carboxylase),
which has shown variation at the population level in selected Tamarix species. DNA sequences will be used
to perform a coalescent-based analysis of allele genealogies (also called a haplorype tree). I will then assess
the geographic structuring of haplotypes, in order to discern if population-specific geographic origins of
invasive haplotypes correlate with their position on the haplotype tree.
Status; I have received and collected samples from putative origins in Eurasia and the invasion in the
western United States. Preliminary analysis suggests that five distinct species are invading. The largest
invasion consists of Tamarix ramosissima, T. chinensis, and a hybrid between these species that is unique
to the invasion. This summer, I will collect in Iran, Turkmenistan, Kazakhstan, and the central and
northwestern U.S. Next fall, I will publish a phylogeny of the genus Tamarix, and continue sequencing and
analysis at the population level.
Papers & Publications; None at this time.
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U915404
EFFECTS OF ALTERED DISTURBANCE REGIMES: LEVEES AND FLOODS
Sarah E. Gergel
University of Wisconsin, Madison
Objectives/Hypotheses; I addressed three major questions regarding the variability and spatial heter-
ogeneity of flood events to determine the long-term ecological consequences of flood-control levees: 1)
How have levees altered the flood regime of the Wisconsin River? 2) How have levees influenced the
relative abundance of flood-tolerant and flood-intolerant floodplain tree species? 3) How have levees
influenced the duration of temporary floodplain ponds?
Rationale; Anthropogenic alterations of disturbance regimes often cause changes in the spatial variability
of disturbance. Despite the ubiquitous disruption of flood regimes on most major rivers, floods are not as
well understood as other disturbances, and few studies have addressed the spatial characteristics of floods.
I examined the influence of flood-control levees on the variability of flood events. Little is known about the
ecological effects of flood-control levees.
Approach; A commonly used hydraulic flood simulation package (HEC-RAS) was used to examine how
spatial characteristics of flood power and extent were altered by levees. Trees were also sampled in the field
on plots along transects in floodplain forest to compare the relative abundance of flood-tolerant and
flood-intolerant species in leveed and unleveed areas. A second spatial simulation model was developed to
determine how levees influence the spatial variability of temporary ponds and wetlands in terms of
connectivity and duration.
Status; I will defend my Ph.D. this summer.
Papers & Publications; Gergel, S.E., Turner, M.G., and Kratz, T.K. 1999. Dissolved organic carbon as
an indicator of the scale of landscape influence on north temperate lakes and rivers. Ecological Applications
9(4): 1377-1390.
Harris, L.D., Hoctor, T.S., and Gergel, S.E. 1996. Landscape processes and their significance to biodiversity
conservation. In: Rhodes, O.E., Chesser, R.K., and Smith, M.H., eds. Population Dynamics in Ecological
Space and Time. University of Chicago Press, Chicago, pp. 319-347.
Gergel, S.E. and Reed-Andersen, T. Modeling ecosystem processes. In: Gergel, S.E. and Turner, M.G.,
eds. Learning Landscape Ecology: A Practical Guide to Concepts and Techniques. Contracted to be
published by Springer-Verlag, New York.
Gergel, S.E. and Turner, M.G., eds. Learning Landscape Ecology: A Practical Guide to Concepts and
Techniques. Contracted to be published by Springer-Verlag, New York.
Gergel, S.E., Turner, M.G., and Mladenoff, D.J. Collecting spatial data at broad scales. In: Gergel, S.E.
and Turner, M.G., eds. Learning Landscape Ecology: A Practical Guide to Concepts and Techniques.
Contracted to be published by Springer-Verlag, New York.
Greenberg, J., Gergel, S.E., and Turner, M.G. Understanding landscape metrics II: effects of changes in
scale. In: Gergel, S.E. and Turner, M.G., eds. Learning Landscape Ecology: A Practical Guide to Concepts
and Techniques. Contracted to be published by Springer-Verlag, New York.
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Turner, M.G., Tinker, D.B., and Gergel, S.E. Patterns in landscape disturbance. In: Gergel, S.E. and Turner,
M.G., eds. Learning Landscape Ecology: A Practical Guide to Concepts and Techniques. Contracted to be
published by Springer-Verlag, New York.
Gergel, S.E. Cumulative impact of levees and dams on the duration of temporary floodplain ponds, (in
preparation)
Gergel, S.E. Impact of levees on ecosystem services from a Midwestern floodplain. (in preparation)
Gergel, S.E., Dixon, M.D., and Turner, M.G. Effects of alterations of disturbance regimes: levees, floods
and floodplain vegetation, (in preparation)
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U915629
EFFECTS OF BIOLOGICAL-PHYSICAL INTERACTIONS ON GENE FLOW
IN MARINE PLANKTONIC POPULATIONS
Erica Goetze
University of California, San Diego
Objectives/Hypotheses; The central goal of this work is to determine the relative importance of physical
oceanographic and biological factors, as well as their interactions, in controlling the extent of gene flow
between populations of pelagic marine organisms. We hope to identify particular biological characteristics
that act either singly, or in conjunction, with the flow field, to critically alter the magnitude and direction of
dispersal.
Rationale; Biological oceanographers and marine biologists have traditionally thought that populations of
holoplanktonic organisms, as well as populations of benthic organisms with a long planktonic larval phase,
disperse over large spatial scales and consequently, have little or no population genetic structure. Although
early field studies in marine population genetics supported this view, more recent work on pelagic copepods
(Bucklin, 1985; Bucklin and Marcus, 1985), euphausiids, benthic giant clams (Benzie, 1998), mussels
(Burton and Feldman, 1982) and sea urchins (Palumbi, 1996) suggest that the patterns may not be so clear.
These species have been shown to have considerable population genetic structure despite high dispersal
capability. Although local natural selection and historical events may in part cause the observed genetic
population structure, these results suggest that the amount of time spent in the plankton may not be a good
predictor of the extent of gene flow in the pelagic. Biological characteristics, such as life history traits, diel
vertical migration patterns, and physiological tolerance, may interact with the flow field and physical
parameters of the environment to modify dispersal patterns and gene flow. Further information on how such
ecological-physical interactions affect population connectivity will be important to understanding main-
tenance of genetic diversity in marine pelagic populations.
Approach; The central questions of this research are: 1) What biological characteristics are important in
determining the magnitude of gene flow between populations of holoplanktonic organisms? 2) What are the
temporal and spatial scales over which gene flow occurs in marine planktonic environments? 3) How does
temporal and spatial variability in advection and diffusion act to control homogeneity of population genetic
structure? A coupled biological-physical ocean modeling approach will be used to examine the research
questions. Stochastic differential equations and kinematic models are being explored for characterization
of the physical component. The biological processes to be coupled with the physical model include
characteristics of the vertical distribution of organisms in the water column (including diel vertical migration,
ontogenetic migration, and seasonal changes in depth distribution), parameters controlling physiological
tolerance to environmental conditions (temperature, salinity, food availability), and reproductive biology
(generation time, asexual and sexual reproductive behaviors). Sensitivity analyses will explore what range
of parameter values critically affect the extent of gene flow.
Status; Pilot modeling studies have explored analytical and numerical solutions to simple physical ocean
models, and the feasibility of incorporating biological components. An additional empirical component to
the research is currently being designed to test the qualitative results of the modeling work.
Papers & Publications; None at this time.
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U915644
UNDERSTANDING BARRIERS TO THE USE OF RENEWABLE ENERGY FOR REMOTE
ELECTRIFICATION BY STATE UTILITIES IN THAILAND
Christopher E. Greacen
University of California, Berkeley
Objectives/Hypotheses; To understand the barriers that state electricity utilities face in the adoption of
least-cost renewable energy technologies for remote electrification in Thailand.
Rationale; Scientists who study global warming call for a massive transition to carbon-free power,
particularly in developing nations. The political power and institutional position of state utilities in many
developing countries make them likely candidates for a substantial role in future efforts to build low-carbon
emitting electricity infrastructure in rural areas. But, characteristics of the renewable energy technologies
that meet these low-carbon objectives require substantially different approaches to system planning and
operation, as well as new ways of relating with recipient communities.
Approach; Thailand presents an interesting case for observing the barriers and opportunities that state
utilities face in adopting stand-alone renewables as an integral part of rural electrification programs.
Thailand's Provincial Electricity Authority (PEA), the country's dedicated rural electricity utility, has
successfully electrified 98.9% of rural Thai villages. The remaining 750+ villages are considered too remote
to electrify with grid extensions. For these villages, the PEA is focusing on the use of stand-alone electricity
generation—either diesel generators or renewable energy systems that harvest local flows of wind, sun, and
falling water. The Thai Government's National Energy Policy Office (NEPO) has taxed the sale of fossil
fuels in the country, creating a substantial fund for energy conservation and renewable energy. The PEA's
"20-islands project" will involve the use of this fund to build renewable energy systems for 20 of Thailand's
unelectrified remote communities.
Through surveys and interviews with inhabitants of the 20-islands villages, participant observation with PEA
engineers, and through interviews with decision-makers, my research seeks to track the adoption of
renewable energy technologies at a variety of levels from the village to the state. Embedded in the planning
process and engineering designs are a number of subjective decisions, each with substantial consequences
for costs, level of service provided, and project sustainability. Through interviews and surveys of villagers,
I hope to understand how demand for electricity services evolves and is socially constructed. Through
interviews and participant observation with the utility engineers, my research seeks to reveal how the utility
comes to understand "demand" and demand growth, and how these and other forces shape system design.
Stand-alone renewables present new design constraints that require new planning approaches and
methodologies that are foreign for utility engineers. How and why are decisions made to address these
constraints? What are the narratives and meanings that accompany renewable energy at the level of the
village, the state utility, and Thai government? The history of rural electrification in Thailand provides the
basis for understanding the symbolic and political importance of electrification that overlay current dialogues
about renewable energy and global climate change.
Status; Conducting preliminary research in Thailand, including language study, participant observation
with the PEA system development division. Expected completion is August 2002.
Papers & Publications; Greacen, C. and Donna, G. 2000. Understanding the technical and social reasons
for solar battery charging system failures in Thailand. Solar Energy (in preparation)
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U915535
PREDICTING MERCURY LEVELS IN FISH: USE OF WATER CHEMISTRY,
TROPHIC ECOLOGY, AND SPATIAL TRAITS
Ben K. Greenfield
University of Wisconsin, Madison
Objectives/Hypotheses; To characterize how lake biological and spatial features influence the con-
centration of mercury in fish.
Rationale; Lake water chemistry, ecological interactions, and a lake's spatial traits may all influence
contaminant accumulation in biota. However, no previous study has simultaneously examined water
chemistry, fish ecology, and landscape processes to evaluate their relative influence on contaminant
accumulation.
Approach: This is a comparative lake survey. With collaborators, I examine the relationship between 26
lake traits and mercury concentrations in yellow perch for 46 northern Wisconsin lakes. Potential predictors
included chemical traits such as pH and water color; biological traits such as fish trophic position and body
condition; and landscape traits, such as lake hydrological position and surrounding wetland abundance.
Status; The lake comparison data set has been analyzed using regression tree and stepwise linear regression
models. pH is the strongest predictor of fish mercury levels (R2 = 0.42; p < 0.001), a result found in
previous studies. Biological traits, such as yellow perch body condition, explain significant additional
variation (p=0.037; final model R2=0.54), but less variation is explained by lake landscape features or
morphometry. Despite the lower significance of landscape traits, a regression tree model determined that
small lakes with greater than 6% wetlands in their watershed are significantly more likely to have elevated
mercury levels. This suggests a useful screening device for identifying hazardous lakes. Fish body condition
is negatively correlated to mercury concentration but positively correlated to water color and dissolved
organic carbon, which may explain why these chemical traits are only weakly related to mercury levels in
planktivores. These results indicate that within-lake chemistry and fish growth patterns are stronger
correlates of mercury levels in yellow perch than spatial traits or fish population abundance.
Papers & Publications; Greenfield, B.K., Carpenter, S.R., Hrabik, T.R., Harvey, C.J., and Kratz, T.K.
Geomorphic and ecological effects on mercury levels in yellow perch [Abstract]. In: Ecological Society of
America 84th annual meeting program; August 8-12, 1999; Spokane, p. 96.
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U915388
CHARACTERIZATION OF MICROBIAL POPULATIONS THAT PRODUCE
TRANS-DICHLOROETHENE (DCE) AS THE MAJOR PRODUCT OF
TETRACHLOROETHENE (PCE) REDUCTIVE DECHLORINATION
Benjamin M. Griffin
Michigan State University
Objectives/Hypotheses; To characterize novel PCE-chlororesptring bacteria and determine factors that
stimulate complete dechlorination of PCE to ethene.
Rationale; Tetrachloroethene (PCE) is a common groundwater contaminant that may undergo stepwise
reductive dechlorination to trichloroethene (TCE), dichloroethene (DCE) isomers, vinyl chloride, and eth-
ene. Complete dechlorination of chloroethenes is desired during natural attenuation and in engineered
bioremediation due to the toxicity of the chlorinated intermediates. Research over the last several years has
improved our understanding of bacteria that reduce PCE to TCE and cis-DCE in a respiratory process
(chlororespiration). However, further studies of the physiology and ecology of chlororespiring bacteria are
needed to determine the factors that stimulate niicrobial communities that completely detoxify chlorinated
ethenes.
Approach; Although PCE and TCE can be completely dechlorinated to ethene, DCEs and vinyl chloride
often accumulate as toxic intermediates. All characterized PCE and TCE degrading bacteria produce
cis-DCE as the major DCE isomer. Five enrichment cultures were derived from river sediment material, and
reduced PCE to trans and cis-DCE in a ratio of 3 (±0.5): 1. Since further dechlorination of DCEs was never
observed in these trans-DCE producing cultures, they may provide insight into why chloroethene reductive
dechlorination often stalls at the level of DCE. I am characterizing the microbial communities using
traditional and molecular techniques. After defining the trans-DCE producing cultures, I will study the
relationship between these organisms and communities that dechlorinate PCE to cis-DCE or ethene.
Status; I have completed physiological characterizations of the trans-DCE producing cultures. I am
currently using molecular techniques to define the enrichments. I am attempting to isolate key dechlorinators
from these cultures and will compare these strains to other pure strains with different dechlorination patterns.
Papers & Publications; None at this time.
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U915464
EVALUATION OF SEMIPERMEABLE MEMBRANE DEVICES (SPMDS) AND IN-VITRO
BIOASSAYS FOR GROUNDWATER MONITORING AT A FORMER COAL-GAS FACILITY
Karl E. Gustavson
University of Wisconsin, Madison
Objectives/Hypotheses; This research evaluates the use of long-term in situ samplers in conjunction with
rapid bioassays to provide a more thorough profile of contamination and potential toxicologic effects than
conventional groundwater monitoring protocols.
Rationale; Groundwater monitoring is typically conducted by withdrawing single 'grab samples' of water
from wells, and analyzing for chemical constituents using GC or HPLC. These conventional techniques
yield only a snapshot profile of groundwater contaminants. However, aquifers are dynamic systems and
contaminant levels can be highly variable with time. These chemical analyses are costly, time-consuming,
provide data only for the selected analytes, and do not assess potential biologic effects of the contaminants.
This research addresses these problems by deploying long-term in situ monitors (semi-permeable membrane
devices [SPMDs]) and evaluating toxicity using in vitro bioassays (Microtox and submitochondrial particle
[SMP] tests).
Approach; Groundwater monitoring wells were sampled at a manufactured gas plant known to contain
polynuclear aromatic hydrocarbon (PAH) contaminated soil and groundwater stemming from previous
coal-gasification activities. SPMDs were deployed within these wells for 28 days and conventional water
samples were taken at the beginning and end of the sampling period. Both water and SPMD samples were
extracted and the extracts analyzed for PAHs by GC-MS and toxicity with the in vitro bioassays.
Status; This portion of the research is completed. The techniques have been extended to other sites con-
taminated by other classes of contaminants. The research portion of my program will be completed in the
fall 2000.
Papers & Publications; Gustavson, K.E. and Harkin, J.M. 2000. Comparison of sampling techniques and
evaluationof semipermeablemembranedevices(SPMDs)for monitoring polynuclear aromatic hydrocarbons
(PAHs) in groundwater. Environ Sci Technol (in review)
Gustavson, K.E., Sonsthagen, S., Crunkilton, R.A., and Harkin, J.M. 2000. Groundwater toxicity assess-
ment using bioassay, chemical, and TIE analyses. Environ Toxicol (in review)
Gustavson, K.E., DeVita, W., Revis, A., and Harkin, J.M. 2000. A novel use of a dual-zone restricted access
sorbent: normal-phase SPE separation of methyl oleate and polynuclear aromatic hydrocarbons stemming
from semipermeable membrane devices. J Chromatogr (accepted)
Read, H., Harkin, J.M., and Gustavson, K.E. 1998. Environmental applications with submitochondrial
particles. In: Wells, P.O., Lee, K., and Blaise, C., eds. Microscale Testing in Aquatic Toxicology: Ad-
vances, Techniques, and Practice. CRC Lewis Publishers, Boca Raton, FL, pp. 31-52.
Gustavson, K.E., Svenson, A., and Harkin, J.M. 1998. Comparison of toxicities and mechanism of action
of n-alkanols in the submitochondrial particle (SMP) and the Vibrio fisheri bioluminescence (Microtox)
bioassay. Environ Toxicol Chem 17:1917-1921.
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U915536
NON-TARGET EFFECTS OF BT CORN POLLEN ON THE MONARCH BUTTERFLY
Laura C. Hansen
Iowa State University
Ob j ectives/Hypotheses; The objectives of this research are to: 1) determine the levels of transgenic pollen
on Asclepias syriaca plants placed within and adjacent to plots of transgenic Bacillus thuringiensis (Bt) corn;
2) assess mortality of Danausplexippus (Lepidoptera: Danaidae) larvae exposed to field deposited pollen;
3) quantify the effects on D. plexippus larvae and adults exposed to a range of transgenic pollen densities
that they would likely encounter in the field; and 4) quantify the use of milkweeds by monarchs, and sur-
vival of monarchs on milkweeds adjacent to Bt and non-Bt corn fields.
Rationale: Starting in the late 1990s, transgenic crops with insecticidal Bt toxins began to be widely planted
in the United States. The expression and dispersal of the Bt toxin in pollen from Bt corn plants may pose
a risk to non-target Lepidoptera similar to that observed from microbial insecticide Bt sprays. When Bt corn
pollen lands on the leaves of plants in and around corn fields, it exposes non-target Lepidopteran larvae
feeding on these plants to Bt toxins. The monarch butterfly, D. plexippus, is a butterfly species that is likely
to be effected by widespread planting of Bt corn. The monarch is widely distributed in North America;
multiple generations are produced each summer and larvae feed exclusively on milkweed plants from early
June to mid September. Thus, the susceptible larval stages are present on milkweeds when corn pollinates.
Approach; Field deposition of pollen was assessed by placing potted milkweed plants within and around
a corn field. Circles of leaf were removed from the milkweed plants and the number of pollen grains on the
circle of leaf was counted. To assess mortality of monarch larvae from field deposited transgenic and
non-transformed pollen, leaf disks (0.79 cm2) were removed from milkweed plants located within and at the
edge of non-Bt and Bt corn plots. A first instar monarch larva was placed on each leaf disk for 48 hours.
To assess the effect of pollen densities similar to those observed in the field, three densities (14, 135, and
1300 pollen grains/cm2) of transgenic (MAX 454, 7333Bt) and non-transgenic (4494) pollen were placed
on a disk of Asclepias curassavica. One 12-36 hr old monarch larvae was placed on each leaf disk.
Following the 48 hr exposure to pollen, each larva was fed clean A. curassavica leaves daily until pupation.
To asses the use of milkweeds in the field, 6 sites with a high concentration of milkweeds adjacent to corn
fields will be chosen, 3 planted with non-Bt hybrids and 3 with Bt hybrids. Monarch larvae using milkweeds
located within 100 m transects at 3 locations adjacent to the field edge (0, 5, 10m) and within the field, will
be counted and instar noted once a week to determine the use of these plants by monarch larvae.
Status; I have currently submitted a paper for publication. I have basically completed work on my first
three objectives. This summer I will conduct surveys of monarchs on milkweed plants in and near corn
fields. I plan to write my thesis this fall and graduate in May 2001.
Papers & Publications; None at this time.
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U915422
THE EFFECTS OF ALTERNATIVE PREY ON A GENERALIST PREDATOR
Jason P. Harmon
University of Minnesota
Objectives/Hypotheses; Agroecosystems contain a variety of spatial and temporal patterns that influence
insect populations and communities. The goals of this project are to better understand how insects interact
with these patterns and explore how patterns of food and habitat resources influence a biological control
agent, Coleomegilla maculata (DeGeer) (Coleoptera: Coccinellidae). This research will help create a
framework for understanding how generalist predators interact with their food in specific habitats and over
the entire landscape. These interactions can be useful for augmenting biological control strategies, im-
proving conservation efforts, and increasing pest management options.
Rationale; Generalist arthropod predators like C. maculata can oppress populations of target prey, yet
interactions with alternative foods often make it difficult to predict the predator's response to different
communities of target and alternative foods. The ladybird beetle C. maculata is a common generalist
predator that can play a significant role in a variety of agricultural and natural systems in the Midwestern
United States. Ladybird beetle abundance and distribution are affected by a community of target and
non-target foods available in crop and noncrop habitats within the agricultural landscape. These habitats
may contain all the resources ladybird beetles need to flourish; however, the availability of these resources
and habitats varies in space and time. It is, therefore, difficult to predict how and why beetles react to
different habitats and landscapes.
Approach: My approach is to understand how the behavior, movement, and reproduction of C. maculata
are affected by the availability of different foods. Within certain crop habitats, I will determine how the
availability, density, and interaction of potential food resource influence the predation, aggregation, and
reproduction of C. maculata. This will be done through a set of empirical studies that investigate C.
maculata's response to combinations of available foods, and its interaction with other characteristics of the
habitat, e.g., vegetation. This information will then be used to model foraging behavior and reproductive
responses to changes in resource availability within fields. Additional models will characterize how C.
maculata moves between patches of food within and between habitats. The predictions generated from these
models will then be tested with further laboratory and field experiments.
Status: I have begun to characterize the response of C. maculata to the most common prey in the corn
agroecosystem. I conducted a study with large field cages to determine how the presence of aphids and
pollen influence the predation of a target prey, European corn borer eggs. My results indicate that: 1) per
capita predation on European corn borer eggs is lower and inversely density dependent when corn pollen is
abundant; 2) predation is higher and density dependent when pollen is absent; and 3) cages with large corn
leaf aphid colonies have small and inconsistent differences in egg mass predation from cages with low aphid
densities, regardless of the presence of pollen. Laboratory studies are helping to show how the type and
density of available foods can influence the foraging behavior of individual C. maculata. I have also begun
a study to understand how C. maculata's movement may be affected by the presence of alternative foods and
other coccinellids. Preliminary analyses suggest that the presence of some foods, such as pollen, may result
in reduced net movement. They also suggest that competition with other coccinellids may depend on the
foods available. This information is being integrated into a general foraging model and a general movement
model to predict how C. maculata responds across a variety of food resources and habitats.
Papers & Publications! None at this time.
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U915360
EVALUATION OF PATTERNS OF LAND COVER BASED
ON CIS AND FUZZY SET THEORY
Thomas B. Harrington, Jr.
Boston University
Objectives/Hypotheses; To quantitatively evaluate and classify patterns of land cover at various scales in
order to assist environmental monitoring and land management for the conservation of biodiversity.
Ecosystem management seeks to combine economic resource use with conservation of environmental
processes and biodiversity by maintaining, in so far as possible, natural conditions, processes, and patterns
on the land. Landscape ecology examines the relationships between patterns of land cover and structure and
environmental processes, such as species population dynamics, habitat suitability, nutrient flows, etc. Many
measures of patterns of land cover have been proposed, but without a methodology for combining them in
order to discriminate degree of difference among landscapes.
Rationale: (Not received at time of printing.)
Approach; This research proposes a methodology that combines geographic information system (CIS)
quantification of land cover pattern with fuzzy set theory for the discrimination of degree of difference in
pattern among landscapes. Sample landscapes are from an industrial forest setting. Each is compared with
a set of three reference patterns depicting different degrees of fragmentation of closed-canopy mature forest.
The focus in the initial research is on patterns defined by stand size and stand density. The comparison
utilizes a pattern state space model: each landscape represents a point in state space determined by its pattern
characteristics. The Mahalanobis distance from each landscape to each of the three reference patterns defines
the degree of similarity between observed and reference patterns, respectively. The interpretation of the
results uses a variety of fuzzy operators that consider, for example, with which reference pattern the observed
landscapes achieve a maximum degree of similarity and how the degree of similarity compares across
reference patterns. The fuzzy set results also enable the estimation of area by reference pattern type.
Whether and how individual landscapes can be aggregated to form higher level (larger) regions having
similar pattern characteristics will be explored.
Status: (Not received at time of printing.)
Papers & Publications; Two papers have been prepared: A Taxonomic Framework for Landscape Pattern
Indicators; and Land Cover Pattern Discrimination Using Fuzzy Set Theory.
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U915622
MANAGEMENT IMPACTS ON POSITIVE FEEDBACKS IN CARBON
AND NITROGEN CYCLES OF GREAT PLAINS GRASSLANDS
Wylie N. Harris
Texas A&M University
Objectives/Hypotheses: The aim of this research is to evaluate impacts of herbivory and fire on carbon and
nitrogen cycling, and the modulatory effect of regional climate on that interaction, in managed native
grasslands of the Great Plains.
Rationale: A conventional view of plant-soil dynamics holds that soil fertility determines the plant
community present on a given site. However, recent evidence suggests that a positive feedback may exist
between plant tissue chemistry and soil fertility. In one model, grazing and burning have opposite effects
on nutrient cycling in mixed C3-C4 tallgrass prairie, with the former fostering enhanced nitrogen availability
and production of high-quality forage, while the latter favors immobilization of N and decreased quality of
forage. The magnitude and rapidity of these shifts are due to the disproportionate importance of a small pool
of labile soil organic matter (SOM) in nutrient cycling. While potentially powerful, this model is based on
data derived from small experimental plots at a single study site; as such, its applicability as a general
predictive tool over the whole of the Great Plains remains to be assessed. Regional climatic variation may
alter the ultimate role of grazing and burning in soil-plant nutrient dynamics. An accurate assessment of the
predicted consequences of grazing and burning, and the degree to which they are modulated by regional
climatic variation, is essential for the development of sustainable resource management strategies and the
quantification of global carbon and nitrogen budgets.
Approach; 1) In order to verify predicted correlations between management history and plant-soil nutrient
relations, plants and soils will be sampled at an array of native prairie sites along a precipitation gradient in
northern Texas. At the beginning and end of the growing season, leaves and roots will be sampled from five
individuals of each biomass-dominant C3 and C4 graminoid species at each site, and soil cores will be taken
from the edge of the root crown and from a point between plants. SOM will be separated by density into
three fractions (active, intermediate, and passive) using a silica-based suspension. Concentrations of carbon
and nitrogen, and the C:N ratio, will be determined on plant tissues and soil organic matter fractions.
Microbial biomass C and N, and potential C and N mineralization rates, will be measured via laboratory
incubations. 2) Mechanistic linkages underlying the correlative phenomena will be assessed intensively by
experimental manipulations at a mixed-grass prairie site in north Texas over a 2-year period. Treatments
are replicated five times each in 36 m2 plots and include: simulated grazing (clipping) at two levels of
intensity (rotational and season-long), with and without manure amendments; burns at two seasons (summer
and winter); and combinations of both burn treatments with the light grazing treatment. All measurements
from Part 1 will be duplicated in Part 2, but at monthly intervals; in addition, laboratory incubations for
potential C and N mineralization will be complemented by in situ IRGA soil respiration measurements (C)
and resin core incubations (N). 3) Regional climatic influences will be assessed by duplicating the sampling
scheme described in Part 1 at an array of sites extending northward along a gradient of increasing
temperature from both extremes of the east-west precipitation gradient sampled in Part 1 to a northern
boundary of 52° N latitude.
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Status: Methods for potential C and N mineralization and for microbial biomass C and N have been
evaluated. Grazing and burning treatments have been initiated at the intensive study site in north Texas.
Field data collection began in May 2000 and will run through the end of the 2001 growing season.
Papers & Publications; None at this time.
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U915368
EXTRATROPICAL TRANSITION OF TROPICAL CYCLONES: CLIMATOLOGY,
LIFECYCLE, AND NUMERICAL SIMULATION
Robert Hart
The Pennsylvania State University
Obiectives/Hvpothesis; To produce the first comprehensive climatology of extratropical transition of
Atlantic tropical cyclones. This process is the transition of a tropical cyclone to a non-tropical (or
extratropical) cyclone once it moves poleward into higher wind shear, colder sea-surface temperatures, and
higher baroclinicity (gradients of temperature). In addition to the climatology, the full tropical cyclone
lifecycle will be realized. Currently, the stage between tropical and extratropical is a region of great
vagueness for both forecasters and researchers. The research will conclude with a numerical simulation of
a case study of extratropical transition, with the goal of understanding the physics and evolution beyond
extratropical transition on the fine scale.
Rationale: These unusual storms represent anomalies from the conventional storms that are seen through-
out the year. They represent unusually difficult forecast problems to both forecasters and researchers, who
do not yet have sufficient conceptual models for such storms. Despite these problems, they present a great
threat (both from wind, rain, and waves) to the Northeast United States, Canadian Maritimes, and western
Europe.
Approach; The climatology and lifecycle examination will be performed through a comprehensive data
analysis using 60 tropical cyclones over 15 years. Satellite-enhanced gridded analyses of 1.1250 resolution
(6-hourly increment) will be used. The numerical simulation stage will focus on the case study of Hurricane
Danielle (1998).
Status; The climatology has been completed and has been accepted for publication. The lifecycle definition
has also been completed and has been submitted for publication. The (final) numerical simulation stage has
started and will be completed prior to graduation in mid 2001.
Papers & Publications; Hart, R.E. and Evans, J.L. 2000. A climatology of the extratropical transition of
Atlantic tropical cyclones. J Climate (in press)
Hart, E.R. and Evans, J.L. 2001. Extratropical transition of Atlantic tropical cyclones: defining the tran-
sition lifecycle using objective indicators of transition, (submitted to Mon Wea Rev, April 2000)
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U915529
MULTIPLE STRESSORS AND AMPHIBIAN POPULATION DECLINES
Audrey C. Hatch
Oregon State University
Objectives/Hypotheses; My overall objective is to investigate the impacts of multiple stressors on developing
amphibians in the Pacific Northwest. In particular, I am focusing on interactions among ultraviolet light (U V),
nitrate fertilizer, and acidification in a laboratory experiment; UV and nitrate fertilizer in an outdoor
microcosm experiment; and UV and oil pollution in an outdoor microcosm experiment. All of these
environmental stressors are relevant to ephemeral ponds in the Pacific Northwest where many species of
amphibians breed.
Rationale: At several locations across the globe, amphibian populations have declined in number and
abundance over recent decades. Habitat destruction, pollution, disease, introduced species, global climate
change and increased ultraviolet (UV) light intensity due to ozone depletion all contribute to the declines.
However, there is probably not one single cause for most amphibian population declines; rather, several
environmental stressors interact in different ways in different regions. My experiments attempt to investigate
some of these interactions.
Approach; My experimental approach integrates fully factorial laboratory and outdoor microcosm experiments
with field monitoring and enclosure experiments. 1 am working with several species that breed in western
Oregon: the long-toed salamander Ambystoma macrodactylunr, the Northwestern salamander Ambystoma
gracile; the Cascades frog, Rana cascadae; the red-legged frog Rana aurora; the Western toad, Bufo boreas;
and the Pacific treefrog, Hyla regilla. Biological endpoints measured include survival, growth, development
time, and predator-prey interactions. The abiotic factors of interest are also monitored in the field.
Status; A laboratory study of three-way interactions among pH, nitrate and UV has been completed, indicating
the potential for all three factors to interact. Outdoor microcosm experiments investigating interactions between
UV, nitrate, and predator-prey dynamics of H. regilla and A. macrodactylum are currently in progress.
Additionally, side projects have investigated the effects of nitrogen fertilizers on juvenile amphibians, and the
effect of UV radiation on schooling and predator avoidance behavior in R. aurora.
Papers & Publications; Hatch, A.C. and Blaustein, A.R. Combined effects of UV, nitrate and low pH reduce
the survival and activity level of larval Cascades frogs (Rana cascadae). (submitted, Archives of Envi-
ronmental Contamination and Toxicology, February 1,2000)
Hatch, A.C., Belden, L.K., Lantz, R., and Blaustein, A.R. The effect of substrate type on avoidance of urea
in juvenile western toads (Bufo boreas). Ethology (in preparation)
Belden, L.K., Wildy, E.L., Hatch, A.C. and Blaustein, A.R. Juvenile Western toads (Bufo boreas) avoid
chemical cues of snakes fed juvenile, but not larval, conspecifics. Animal Behaviour (in press)
Blaustein, A.R., Kiesecker, J., Chivers, D., Hokit, D.G., Marco, A., Belden, L.K., and Hatch, A.C. 1998.
Effects of ultraviolet radiation on amphibians: field experiments. American Zoologist 38:799-812.
Hatch, A.C. and Burton, G.A., Jr. 1998. Effects of photoinduced toxicity of fluoranthene on amphibian
embryos and larvae. Environ Toxicol Chem 17:1777-1785.
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U915361
SPECTROSCOPIC CHARACTERIZATION OF ORGANIC AEROSOLS
Cindy D. Hauser
University of North Carolina, Chapel Hill
Objectives/Hypotheses; The focus of these studies is on the development of the in situ spectroscopic
methods necessary to characterize gas-particle systems under ambient conditions and to apply these to better
understand the nature of atmospheric particulates.
Rationale; This research specifically addresses the problem of characterizing and monitoring the fine
fraction of atmospheric aerosols (particulate matter of diameters 2.5 mm or less: PM2 5) that are linked to
health effects and now subject to regulation. The semi-volatile nature of these particles makes their detailed
characterization difficult, since all sampling methods tend to perturb the delicate equilibrium that exists
between the gas and particle phases.
Approach; Two analysis methods are currently employed to characterize the composition and hetero-
geneous chemical behavior of organic aerosols. In the first, a heated stream of nitrogen is used to evaporate
multi-component aerosols. The resulting vapor is analyzed using conventional FTIR spectroscopy. The
fractional composition can be determined as a linear combination of the individual components. The second
method involves suddenly disturbing the gas-particle equilibrium and monitoring the system as it returns to
equilibrium. A pulsed CO2 laser is being used to heat the cross-section of an aerosol stream flowing through
a sample cell equipped with a White Cell optical configuration for enhanced detection, while a step-scan
FTIR spectrometer monitors the gas phase species at times before and after the CO2 laser perturbs the
aerosol. This technique monitors the diffusion of volatile and semi-volatile components from the
particle-phase to the gas-phase and the return of the system to equilibrium in the nanosecond time regime.
The microphysics of the aerosol-laser interaction, necessary for accurate interpretation of the vapor transient
profiles, are studied by monitoring the size of the aerosol particle via light scattering techniques.
Status; The application of time-resolved infrared spectroscopy to the in situ real-time analysis of laboratory
generated aqueous and organic aerosols, specifically formamide, has been demonstrated. Preliminary light
scattering studies of the evaporation process reveal primary particle shattering with a high fraction of
vaporization followed by secondary particle evaporation, the extent of which depends on particle
composition and increases with increasing pulse intensity. Analysis of heated multi-component organic
aerosols using conventional FTIR is providing qualitative and quantitative information on aerosol
composition. Results from these studies indicate a potential application of these methods in the investi-
gation of heterogeneous chemical properties of aerosols. Project completion is expected in August 2001.
Papers & Publications; None at this time.
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U915335
INTERACTION BETWEEN GRAZING AND NUTRIENTS AS CONTROLS
OF MACROPHYTE BIOMASS AND COMMUNITY STRUCTURE
IN SHALLOW TEMPERATE ESTUARIES
Jennifer A. Hauxwell
Boston University
Objectives/Hypotheses: To understand how anthropogenic nitrogen inputs, grazing by benthic invertebrates,
andcompetitiveinteractionsbetweenmacroalgae and seagrasses influence macrophytebiomass and community
structure (seagrass- or macroalgal-dominated) in shallow temperate estuaries.
Rationale: Increasing delivery of anthropogenic nitrogen from watersheds causes a suite of changes in
estuaries, beginning with primary producers. High nitrogen-loads result in increased growth of phytoplankton,
unattached benthic macroalgae, and macro- or micro-algal epiphytes on eelgrass (Zostera marina). The thick
canopies of macroalgae that may accumulate on the bottom of the receiving estuaries, as well as the increased
phytoplankton and epiphyte biomass, may shade and eventually replace light-limited eelgrass meadows. The
resulting change in habitat alters the abundance and composition of benthic fauna, including the likely toss of
commercially valuable winter flounder, white hake, Atlantic cod, American lobster, and scallops that utilize
eelgrass habitat during early stages of their life history. In addition to nitrogen-load, grazing may also be an
important control of macrophyte (macroalgae and seagrass) biomass and community structure in coastal
embayments. Several studies suggest that grazers may actually help maintain eelgrass beds by consuming
benthic macroalgae and/or epiphytic algae that contribute to light-limitation of eelgrass.
Approach: To determine how nutrient supply, grazing, and interactions between macroalgae and seagrasses
influence macrophyte biomass and community structure, I have collected experimental and descriptive field
data from different estuaries of Waquoit Bay, MA, that are exposed to different nitrogen loads. I have
conducted monthly benthic surveys for one year to assess macroalgal and eelgrass biomass and areal coverage,
and invertebrate grazer abundances. Additional field data have included annual eelgrass growth rates and shoot
density, which will allow estimation of production. I have modeled grazer impact on macroalgal biomass based
on: 1) survey data, 2) field grazing rates by abundant herbivores on their algal foods, and 3) in situ macroalgal
growth measurements. To understand the interaction between macroalgal canopies and eelgrass production,
I have conducted a field experiment in which I either excluded macroalgae from plots of eelgrass or included
macroalgae at differing canopy heights (corresponding to levels observed in estuaries of different nitrogen
loads), and measured the impact on eelgrass density and growth. I am currently analyzing data necessary to
determine eelgrass production and overall health, epiphyte loads, and phytoplankton and macroalgal biomass
in estuaries receiving different nitrogen loads from watersheds.
Status; Field and laboratory work are completed, and I am in the process of writing.
Papers & Publications; Hauxwell, J., Cebrian, J., Furlong, C., and Valiela, I. Macroalgal canopies contribute
to eelgrass (Zostera marina) decline in temperate estuarine ecosystems. Ecology (in press)
Hauxwell, J., McClelland, J., Behr, P.J., and Valiela, I. 1998. Relative importance of grazing and nutrient
controls of macroalgal biomass in three temperate shallow estuaries. Estuaries 21 -.344-357.
Hauxwell, J., Cebrian, J., and Valiela, I. Annual dynamics of eelgrass (Zostera marina) production along a
gradient of nitrogen loads from watersheds to estuaries: assessment of tools for management of these coastal
habitats, (in preparation)
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U915219
EDGE EFFECTS ON CARBON AND NITROGEN CYCLING IN FRAGMENTED
OLDGROWTH FORESTS OF THE PACIFIC NORTHWEST
Tom D. Hayes
University of California, Berkeley
Objectives/Hypotheses; My objective is to address the indirect impact of clearcut edges on biogeochemical
processes affecting nitrogen (N) retention within adjacent fragmented oldgrowth Douglas-fir forests in the
Pacific Northwest. This project examines the relationship between the magnitude of the edge effect on
biogeochemical processes and the distance the effect penetrates into the forest, in order to more accurately
predict the influence of land use on regional biogeochemical processes. The overall hypothesis is that
increased microclimate variability induced at oldgrowth forest-clearcut edges increases biogeochemical
cycling rates and reduces net ecosystem productivity in forest fragments.
Rationale; Induced edges between habitat patches are now a dominant feature of landscapes, yet the
biogeochemical consequences of edges have received little attention. Altered nutrient cycling at edges has
important implications to conservation strategies, forest productivity, and global climate change.
Approach; Prior research has documented edge effects on microclimate and vegetation at the field site in
Wind River Experimental Forest in southern Washington. Initial field and laboratory assays of N
mineralization, litter decomposition, and related soil processes reveal increases in C loss and N availability
in near-edge (0-30 m from edge) forest soils, and higher rates of litterfall and C storage within far-edge
(30-120 m) forest, relative to interior forest (more than 120 m). Also, south-facing forest edges have greater
magnitude of effect and depth of influence for all assayed processes, relative to north-facing edges. Initial
results were used to design a 3-year experiment, which concurrently measures edge effects on microclimate,
litterfall, decomposition, N mineralization, and forest structure.
Status; I expect to complete remaining field work this June, and am working on final lab analyses and data
analysis. I will finish writing my dissertation in fall 2000.
Papers & Publications; None at this time.
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U915403
A THOUSAND PIECES OF PARADISE: NATURE, PROPERTY,
AND COMMUNITY IN THE KICKAPOO VALLEY
Lynne Heasley
University of Wisconsin, Madison
Objectives/Hypotheses; This study traces the environmental history of one valley in the rural Midwest.
I focus on spatial and historical relationships among land tenure, land use and the landscape of the Kickapoo
Valley. At the same time, I contrast these visible relationships to society's less-visible, shifting ideas about
property and nature. The research involves history, ecology and geography, all of which are crucial for
answering my central questions: How have ideas about property and nature been articulated in real-life
relationships among people in the Kickapoo Valley? How have they taken shape on the landscape? Can we
measure the environmental consequences of our land tenure arrangements? And finally, why has society
set property and nature, one against the other, when they are both so intrinsic to our everyday lives?
Rationale: Midwesterners maintain complex cultural and ecological connections to their rural landscapes.
These connections have profound consequences for sustainable land use, yet they can be difficult to study
because the natural sciences and the social sciences have approaches that are often at odds. The dilemma
extends beyond disciplinary boundaries, with ramifications for natural resource managers, policy makers,
communities, and landowners, who must incorporate a wide range of cultural, economic and ecological
information in their decisions. This research provides the spatial and historical discrimination so essential
to (but sometimes missing from) research on our most vexing national debates over property and the
environment.
Approach; I integrate the approaches of environmental history and landscape ecology. To gain the spa-
tially explicit, quantitative insights typical of landscape ecology, I developed a GIS, which documents land
tenure and the landscape of three townships at six dates back to the 1930s. I fold this work into a larger
narrative emerging from archival research and interviews with Kickapoo Valley residents, as well as maps
from the GIS.
Status; I hope to defend my dissertation in August 2000.
Papers & Publications; Heasley, L. and Curies, R.P. 1998. Forest tenure and cultural landscapes:
environmental histories in the Kickapoo Valley. In: Who Owns America? Social Conflict Over Property
Rights (Harvey M. Jacobs, ed.). Madison, WI: University of Wisconsin Press.
124
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U915647
ASSESSING THE USE OF GENETICALLY ENGINEERED PLANTS
TO REMEDIATE MERCURY CONTAMINATED SOILS
Andrew C. Heaton
University of Georgia
Objectives/Hypotheses; Plants engineered with the bacterial mercuric ion reductase gene, merA, will be
capable of removing Hg(II) from polluted soils and volatilizing it as the much less toxic Hg(0). Plants may
be further engineered to absorb Hg(II) from contaminated soils and store it in harvestable shoots and leaves.
Rationale; Industrial practices have released mercury into many environments that now require re-
mediation. Because current remediation strategies are costly and site-destructive, we are developing an
alternative mercury remediation strategy. We have engineered several plant species with the bacterial
mercury resistance gene, merA. MerA enables plants to chemically reduce soil-absorbed Hg(II) to less toxic
Hg(0), which is then volatilized. I have been assessing the ability of merA plants to remove Hg(II) from
various growth substrates and detoxify this form to Hg(0). Next, I will attempt to engineer a novel plant
which should be able to remove Hg(II) from the soil and store it in aerial tissues for later harvest and
hazardous waste disposal.
Approach; I am working almost exclusively with merA-transformed N. tabacum (tobacco) as a model
species. My initial studies focused on comparing the survival and growth of merA versus wildtype tobacco
plants grown in Hg(II)-spiked soils. MerA plants survived in soils of sufficient mercury concentration to
kill wildtype plants. As a more quantitative estimation of the Hg(II)-processing capability of merA plants,
I will measure Hg(0) volatilization from plants growing under a variety of conditions that simulate the field
environment. I will learn the fundamentals of genetic engineering by transforming tobacco plants with the
merA gene under the control of a root-specific promoter. The plants will have already been modified by
another researcher such that they produce high levels of metal-binding protein in the aboveground tissues.
Plants engineered in this way should be able to sequester most root-absorbed Hg(II) in the aerial tissues. If
I am successful at engineering such a plant, I will measure Hg(0) volatilization and the tissue Hg(II)
sequestration by these plants growing in hydroponics and perhaps soil.
Status; MerA tobacco and Arabidopsis have already been grown on a variety of mercury contaminated
substrates in order to demonstrate the ability of these merA plants to detoxify root-absorbed Hg(II). I have
constructed a small clamping leaf chamber for the purpose of measuring Hg(0) volatilization from merA
tobacco plants. We have begun to engineer plants with the capacity to sequester root-absorbed mercury in
leaf and shoot tissues. I have introduced the merA gene controlled by a root-specific promoter into tobacco.
Another member of the Meagher lab has engineered tobacco plants with enhanced metallothionein
production specific to aboveground tissues. We will cross these plants within the next few months to yield
what may be a mercury sequestering plant for use in mercury phytoremediation.
Papers «& Publications; Heaton, A.C.P., Rugh, C.L., Wang, N.-J., and Meagher, R.B. 1998. Phyto-
remediation of mercury- and methylmercury-polluted soils using genetically engineered plants. J Soil
Contam 7(4):498-509.
Rugh, C.L., Heaton, A.C.P., Wang N.J., and Meagher, R.B. 2000. Altered mercury processing in plants
expressing bacterial mercuric ion reductase. (in preparation)
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U915638
ACCUMULATION OF 4-NONYLPHENOL (NP) IN SHORT ESTUARINE FOOD CHAINS
POTENTIALLY LEADING TO ENDOCRINE DISRUPTION IN CHINOOK SALMON FRY
Scott A. Hecht
Oregon State University
Objectives/Hypotheses; The overall hypothesis of my research is that transmission of NP will take place
through short grazer/consumer food chains in estuarine systems and this will be sufficient to trigger
endocrine disruption in chinook salmon fry.
Rationale; Chinook salmon populations have been in steady decline for several decades in areas of the
Pacific Northwest. Most likely, the decline is caused by a combination of cumulative impacts including
habitat loss, dam construction, over-fishing, and contamination of water and sediments by organic and metal
pollutants. My research project focuses on the latter with emphasis on NP contaminated sediment. The EPA
is awaiting data to determine what use and emission regulations should govern NP. It is a surfactant
breakdown product that is not regulated and exhibits aquatic toxicity including disruption of endocrine
systems of Salmonids. Questions remain concerning the primary route of exposure of fish to NP. This
research investigates the potential for 4-nonylphenol to move up through estuarine food chains resulting in
endocrine disruption in salmon fry.
Approach: Standard laboratory, sediment, toxicity bioassays are used to investigate bioaccumulation from
sediments to amphipods and toxicity to amphipods. Three sets of experiments will be conducted to deter-
mine these objectives. In the first set, two experiments were run in parallel, one with sediments spiked with
14C-NP and one with sediments spiked with 14C-PCB. Uptake of NP by amphipods was compared to PCB
uptake across three treatments, consisting of sediments enriched with organic carbon of different nutritional
qualities. In the second set, sensitivity of amphipods and phytoplankton to NP will be investigated. The
third set of experiments will determine if induction of vitellogenin can occur from salmon fry feeding on
amphipods that have bioaccumulated NP from contaminated sediments or algae.
Status; During the spring of 2000, bioaccumulation of NP from spiked sediments by estuarine amphipods
was investigated. Growth inhibition tests have been conducted for Pseudoisochrysisparadoxa. Endocrine
disruption tests in salmon are planned for fall 2000.
Papers & Publications; Hecht, S., Gunnarsson, J.S., Boese, B., Lamberson, J.O., and Giger, W. Uptake
and accumulation of 4-nonylphenol in estuarine amphipods in response to refractory and labile organic
matter, (in preparation; to be submitted to Environmental Toxicology and Chemistry)
126
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U915601
CHARACTERIZING FIRE REGIMES IN CONIFER FOREST
USING OPTICAL AND MICROWAVE REMOTE SENSING
Mary C. Henry
University of Arizona
Objectives/Hypotheses; The goal of this research is to address current fire ecology questions and test the
limits of remote sensing for these applications. 1) What is the spatial variability in fire-induced vegetation
mortality and recovery? 2) What are the effects of differing fire histories on spatial variability in canopy
cover and forest structure? 3) Can these patterns be resolved using currently available remote sensing data?
Rationale; Humans have caused dramatic changes in fire regimes of the western United States over the last
century through fire suppression and livestock grazing. Fire history is of unknown importance to deter-
mining community response to fire, as well as land management planning and prescribed burning. However,
if there is a link between fire history and forest spatial patterns, and remote sensing can be used to detect
these patterns, then forest managers attempting to restore fire to ecosystems will have an additional tool.
Furthermore, fire history information could be combined with fuel load inventories to indicate fire risk.
Approach; This research is being conducted as three case studies. Case Study One uses only optical image
data to a) characterize spatial patterns in areas of differing fire history, and b) compare spatial patterns in
pre- and post-fire images for various fires. Spectral vegetation indices (SVIs) including the Normalized
Difference Vegetation Index (NDVI) and Tasseled Cap Transform will be calculated for several Landsat
Thematic Mapper (TM) images. For the single date portion of the study (part a), pixel values for plots of
known fire history will be extracted from a single image and Moran's I calculated. Spatial autocorrelation
changes over distance will be compared for plots with similar fire history to determine if a relationship exists
between fire history and spatial pattern. In part (b) of this study, pixel values for one pre-fire and at least
two post-fire images will be extracted and Moran's I calculated. The remaining Case Studies will use active
microwave data (Case Study #2) and optical-microwave data fusion (Case Study #3) to follow similar
protocols.
Status; Case Study One is in progress and initial results suggest that a relationship exists between fire
history and forest spatial patterns. Continuing work will consider additional SVIs, directional spatial
autocorrelation patterns, as well as the multi-temporal part of the study. Modifications to the study plan will
include calculation of local spatial autocorrelation measures and identification of potential problems caused
by variable topography. Case Study One should be completed this October, with the entire dissertation being
finished summer 2002.
Papers & Publications; Henry, M.C. 2000. Characterizing fire-related spatial patterns in the Arizona Sky
Islands using landsat thematic mapper data. Presented at the Annual Meeting of the Association of American
Geographers. Pittsburgh, PA, April 4-8,2000.
Henry, M.C. 1999. Characterizing fire regimes in conifer forest using optical and microwave remote
sensing. Presented at the Annual Meeting of the Association of American Geographers. Honolulu, HI,
March 24-27,1999.
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U915411
ECONOMIC REFORM, NCOS AND CRANES IN RUSSIA AND CHINA
Melinda K. Herrold
University of California, Berkeley
Objectives/Hypotheses: In villages around the two protected areas, Caohai Nature Reserve in southwestern
China and Muraviovka Park in the Russian Far East, my research focuses on determining to what extent the
rural development and education initiatives of NGOs have mitigated natural resource conflicts between local
people and nature reserve managers.
Rationale; As the world's two largest and most powerful socialist economies, the former Soviet Union and
the People's Republic of China, have undertaken major market-oriented reforms, international nongovern-
mental organizations (NGOs) have come to play an increasingly important role in the protection of Russian
and Chinese wildlife. In Russia and China, local resource use is now increasingly influenced by economic
liberalization and the conservation and development programs of international NGOs. In recent years,
researchers have found that economic reforms in Russia and China have encouraged practices that are
degrading habitat for rare species. Simultaneously, economic reforms have resulted in institutional changes
that have created a space in which international NGOs can reinforce or even replace state protection efforts.
This research has both practical and theoretical implications. It will contribute to a practical understanding
of the effectiveness of NGO programs to preserve endangered species, while contributing to a more
theoretical understanding of the impact of global trends upon local environments and endangered species.
Approach: By recognizing both macro-level forces and micro-level politics that lead to changes in natural
resource use, the methods of this study are heavily informed by the approach of political ecology. A hall-
mark of political ecology is the combination of anthropological field research with political economic
analysis (Bryant and Bailey, 1997, 17). This approach begins with the concrete actions of resource users,
then examines how these actions are influenced by the larger political and economic context (Neumann,
1992, 87). My methods include anthropological methods such as interviews, oral histories, participant
observation, and participatory mapping with those individuals directly involved in the use of natural re-
sources (e.g., farmers, fishermen, local government officials, nature reserve managers) in my two study sites.
The aim of these activities will be to learn how local people use resources; why local people make the
decisions they do concerning resource use; how these uses have changed over time; and what external factors
(e.g., government policies, NGO programs, market conditions) influence their behavior. Additionally,
archival research and interviews with local people, government officials and NGO representatives will
furnish information about the larger political-economic context in which natural resource users make their
decisions.
Status: I am currently in the middle of my second season of field research. During this season, I will spend
12 months in two villages surrounding Muraviovka Park in the Russian Far East. In July 2000,1 will return
to Caohai Nature Reserve in China for four more months of research.
Papers & Publications: Herrold, M. Cranes and field work in Cao Hai, China. Geographic Review (forth-
coming)
128
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STAR Graduate Fellowship Conference
U915235
DISPERSAL ON STRUCTURED HETEROGENEOUS LANDSCAPES
David E. Hiebeler
Cornell University
Objectives/Hvpotheses; I am investigating the role of spatially structured habitat distributions on popu-
lation density and on the evolution of dispersal. I am also working with others, trying to estimate dispersal
parameters in Tree Swallows (Tachycineta bicolor) by correcting for the inherent bias present in any
mark-recapture experiment within a limited spatial area.
Rationale; The loss and fragmentation of habitat suitable for natural populations is of great concern. Some
of my work is intended to assess how populations will respond to changing land-use patterns. Also, dispersal
is a key element of an individual's life history, but it is also extremely difficult to measure emprically, since
when an individual disappears from the study area, it is impossible to know whether it was due to dispersal
or death.
Approach; Computational stochastic spatial models of populations on landscapes with spatially structured
(i.e., clustered) habitat distributions are being studied; mathematical approximations are being studied
analytically, primarily via techniques such as pair approximations. Finally, statistical models of dispersal
in Tree Swallows are being investigated on capture data gathered by Prof. David Winkler at Cornell, to try
and correct for spatial biases inherent in such studies.
Status; The computational and mathematical models are fairly well-developed, and I hope to write two
papers on these results very soon.
The Tree Swallow project is doing well conceptually, but there are many computational difficulties along
the way. However, we are making progress, and also hope to be writing a paper on that topic very soon.
Papers & Publications; Hiebeler, D.E. 2000. Populations on fragmented landscapes with spatially
structured heterogeneities: landscape generation and local dispersal. Ecology (in press)
129
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STAR Graduate Fellowship Conference
U915229
FISH, FOREST PLANS AND FAIRNESS: CREATING A
NATURAL RESOURCE COMMONS IN SOUTHWEST MONTANA
Lorie L. Higgins
Washington State University
Objectives/Hypotheses: The purpose of this study is to gain a theoretical understanding of the changing
character of natural resource decision making. Increasing recognition that conventional understandings and
rational-analytical approaches to problem solving are inadequate has led to widespread experimentation with
innovative strategies for involving the public in management decisions. This research traces and examines
contemporary efforts to create fair and effective systems of access to and use of common resources in the
rural West by comparing a conventional public participation approach in eastern Washington with two
experimental approaches in southwestern Montana.
Rationale: The recent expansion and characteristics of experimentation with collaborative processes
involving diverse stakeholder groups suggests a steady, though fragmented and disorderly movement toward
efforts to create an adequate system of access and use rights to common resources. It is important to know
if this burgeoning interest in cooperative interests has moved communities and decision makers toward better
models for creating functional commons traditions, to understand the reasons for the stuttering pace of
diffusion and development, and to identify the social organizational changes needed to produce better
models.
Approach: I am using the methods of participant observation, depth interviewing, and document analysis
to examine the progress of individual processes and whether norms of collaboration are developing at the
local and regional level as a result of local and state efforts. My primary focus is on processes that arise in
a particular sub-region of communities that share concerns about common resources. Thus, rather than using
attributes of cases as a sample basis, I have chosen to study a geographical region and the collaborative
processes that exist there, regardless of their level of success or specific issues addressed. Exogenous forces
at the regional and national/global level affecting the context in which those processes operate are analyzed
in addition to the internal dynamics of each collaborative group. Data is analyzed using grounded theory
methodology and qualitative data analysis software.
Status; I am currently in the writing and theoretical sampling phase of the research, in which additional
observationsare guided by evolving theoretical constructs. This project will be completed in December 2000.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915565
DRAWING OF FLEXIBLE CHAIN POLYMERS IN HIGH PRESSURE CO2
Terry R. Hobbs
University of Massachusetts, Amherst
Objectives/Hypotheses; To develop a scientific and engineering understanding of the interaction of CO2
with polymers at various levels including the continuum level. The results will aid in the development of
new low energy, benign processing techniques for polymer processing, textile dyeing, and the production
of high performance fibers.
Rationale; The use of solvents in fiber processing including drawing and spinning is highly undesirable
because of air and wastewater contamination. This research will aid in the scientific understanding of
polymer deformation and the removal of hazardous solvents from various processing stages. In addition,
the research establishes an environmentally friendly route to fibers with unique structures and morphologies.
Approach; High pressure equipment has been built to study polymer deformation including isothermal cells
and a high pressure tensile drawing apparatus. The approach is experimental where polymers are drawn in
CO2 or investigated using dynamic measurements. The resultant materials are analyzed using a variety of
physical techniques including x-ray diffraction, differential scanning calorimetry, polarized light micro-
scopy, density, and scanning electron microscopy. Mechanical measurements are used as well to obtain
engineering properties.
Status; Currently, I am writing my Ph.D. thesis and expect to complete my degree in the summer of 2000.
Papers & Publications; Hobbs, T. and Lesser, A. 1999. In situ drawing of high molecular weight
poly(ethylene terephthalate) in subcritical and supercritical CO2. J Polym Sci, Part B: Polym Phys,
37:1881-1891.
Hobbs, T. and Lesser, A.J. 2000. Preparation of high performance poly(ethylene terephthalate) fibers:
two-stage drawing using high pressure CO2 polymer, (in print)
Hobbs, T. and Lesser, A.J. 2000. Drawing in high pressure CO2—a new route to high performance fibers,
polymer engineering and science, (accepted)
Hobbs, T. and Lesser, A.J. 2000. Drawing of nylon 6,6 fibers in high pressure CO2. ACS Preprints:PMSE.
(in print)
131
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U915549
EVALUATION OF HYDROLOGIC AND WATER QUALITY BENEFITS
OF INFILTRATION-BASED URBAN STORMWATER MANAGEMENT
Jennifer K. Holman-Dodds
University of Iowa
Objectives/Hypotheses: To better understand the processes that control urban stormwater quantity and
quality and to address the potential of low-impact, non-structural stormwater management strategies using
hydrologic modeling.
Rationale; There is little doubt that humans have caused significant impacts on the natural environment
through urbanization, including alterations to watersheds and the hydrologic cycle. In the past, stormwater
management strategies have focused on the mitigation of localized peak flow impacts, usually with detention
ponds. While this may change the timing of the flows, the increased stormwater volume resulting from
increased impervious areas is largely unaffected. In recent years, alternative approaches for dealing with
urban stormwater have been proposed. Ths idea is to carefully manage surface water from impervious
surfaces to promote infiltration on adjacent pervious surfaces. Furthermore, it may be possible to implement
additional measures to enhance the infiltration properties of the pervious surfaces, perhaps through the use
of native vegetation. The exciting aspect of such an approach is that there is the potential to reduce the
amount of surface runoff, recharge local groundwater aquifers and streams, reduce erosion and stream
widening, and improve stream water quality, all without the expense and maintenance associated with cur-
rent stormwater infrastructure.
Approach; In order to gain a broad-based understanding of urban stormwater infiltration and runoff, we
will combine field observations with numerical hydrologic modeling. The first phase of this project will
include gathering existing information and developing some simplified preliminary analyses to help clarify
the important issues and processes that govern this problem. The second phase will include field infiltration
measurements to explore the influence of type of vegetative cover on the infiltration rate, as well as the
evolution of infiltration rate over time as vegetation is established. The third phase will approach the
problem using computational hydrologic models at a variety of scales. Small-scale modeling will be used
to examine local water budgets, infiltration patterns, and runoff and contaminant transport patterns. This
will be complemented by large-scale modeling to better understand how the effects of local stormwater
management strategies aggregate at the scale of a small watershed.
Status; Preliminary research and simplified analyses suggest that using native vegetation to manage
stormwater infiltration shows promise. Field work will be undertaken this summer to better quantify the
effect of vegetation on infiltration rates. Concurrently, appropriate hydrologic models will be selected and
adapted to prepare for the modeling phase of this work.
Pacers & Publications; None at this time.
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U915556
A LAND SURFACE PROCESS/RADIOBRIGHTNESS MODEL
FOR AGRICULTURAL TERRAIN
Brian K. Hornbuckle
The University of Michigan
Objectives/Hypotheses; The goal of my research is to develop satellite microwave remote sensing tech-
niques which can be used to monitor the storage of water in soil and the transfer of water between the soil,
vegetation canopy, and atmosphere.
Rationale; A layer of soil just below the surface of the earth holds the water that can potentially be removed
from the soil by evapotranspiration. This quantity of water is called the total stored water. Satellite
microwave remote sensing instruments called radiometers measure the amount of microwave radiation, or
radiobrightness, emitted by the earth's surface. Radiobrightness is related to near-surface soil moisture, the
amount of water in the first few centimeters of the soil. Unfortunately, the layer of soil that contains the total
stored water is normally at least one meter deep. Consequently, near-surface soil moisture and the total
stored water are often very different quantities. This incompatibility has been rectified by the creation of
land surface process/radiobrightness (LSP/R) models, which relate satellite-measured near-surface soil
moisture to the total stored water. When given local meteorological data, such as air temperature, relative
humidity, wind speed, precipitation, and solar radiation, LSP/R models produce estimates of the total stored
water and evapotranspiration, as well as near-surface soil moisture and the corresponding radiobrightness.
As time passes, the accuracy of the predictions deteriorate, simply because complex physical processes
cannot be represented exactly by mathematical equations. Future LSP/R models will compare their
predictions of radiobrightness to actual satellite measurements of radiobrightness and use the difference to
improve subsequent predictions of the total stored water and evapotranspiration.
This research will contribute to the construction of LSP/R models that assimilate satellite measurements of
radiobrightness and could be used to estimate the total stored water and evapotranspiration on regional
scales. Recent investigations have shown that the surface flux of persistent organic pollutants (POPs) such
as DDT, PCBs, and dioxins may be correlated with the flux of water across the land-atmosphere interface.
Plants are expected to play a very important role because of their large surface area and high organic content.
To determine the environmental fate of POPs using global dispersion models, it will be crucial to quantify
POP surface flux. By developing LSP/R models for different types of vegetation canopies, future satellite
radiometry missions may present a unique opportunity to model the transport of POPs on a global scale.
Approach: The relationship between radiobrightness and near-surface soil moisture depends largely on the
type of vegetation cover. I will develop a LSP/R for agricultural terrain. Besides modeling how water is
exchanged between the soil, vegetation canopy, and atmosphere, I will also construct new probabilistic
models to predict how microwave radiation emitted by the soil propagates through a vegetation canopy
before being intercepted by a radiometer. To test my LSP/R model, I will collect meteorological, soil, and
radiobrightness data in an agricultural field during a summer 2000 field experiment.
Status; I am currently writing the plan for this summer's field experiment, which will take place in a
cornfield in Southeastern Michigan.
Papers & Publications; None at this time.
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U915220
RELATIONSHIPS BETWEEN GROUND WATER AVAILABILITY
AND RIPARIAN TREE PHYSIOLOGICAL CONDITION AND GROWTH
Jonathan L. Horton
Northern Arizona University
Objectives/Hypotheses; The objective of my research is to understand mechanistic relationships between
ground water availability, tree physiological condition, and growth in two native riparian tree species,
Populus fremontii and Salix gooddingii, and one invasive exotic, Tamarix chinensis. Specifically, I am
addressing the following questions: 1) Do water sources used by riparian trees change as ground water
availability changes? 2) If so, do changes in water sources affect tree physiological condition and growth?
3) And if so, what ground water depths maintain healthy riparian trees?
Rationale: Riparian forests are a threatened, yet valuable, ecosystem type in the southwestern United States.
Altered surface flow and ground water withdrawals are hypothesized to be important causes of stress to these
ecosystems. However, there are gaps in our understanding of ground water requirements of southwestern
riparian trees. Given the growing demand for water by urban populations in the Southwest, knowledge of
the relationships between ground water depth, riparian tree water uptake, physiological condition and growth
may greatly enhance management efforts to conserve or restore riparian ecosystems.
Approach; I conducted research at two Sonoran Desert river systems in Arizona. The Bill Williams River
is a dam-regulated system, while the Hassayampa River is free flowing. Research was done at both rivers
in 1997. In 1998, the occurrence of strong el Nino event caused surface flow and ground water to be higher.
I did research at the Hassayampa River in 1998 in order to compare tree physiological condition between
a dry year (1997) and a wet year (1998). At a losing reach at each river, I established seven transects along
a gradient of depth to ground water. At each transect, 2 to 4 ground water monitoring wells were installed.
Depth to ground water and soil water content were monitored at each transect. Leaf gas exchange, xylem
water potential, canopy condition, branch elongation, and radial growth were measured on all species at each
transect. Ground, stream, soil, and xylem waters were collected for stable isotope analysis in order to
determine ecosystem water sources used by riparian trees. Analysis of variance and regression techniques
were used to compare leaf physiological characteristics, canopy condition, and xylem isotopic ratios among
sample locations, species, and years.
Status; I have completed both field seasons and have summarized the physiological data into manuscripts
that are currently in review. In the summer of 1997,1 attended a course on the use of stable isotope analysis
in ecological research taught by Dr. James Ehleringer at the University of Utah. With knowledge gained
from that course, I have constructed vacuum lines in our laboratory for the preparation of water samples for
stable isotope analysis. Many of these samples have been sent to the Stable Isotope Ratio Facility for
Ecological Research at the University of Utah for analysis. All analyses should be complete by August 2000,
when I hope to graduate.
Papers & Publications; Horton, J.L. and Clark, J.L. Water table decline alters growth and survival of Salix
gooddingii and Tamarix chinensis seedlings. Forest Ecology and Management (in press)
Horton, J.L., Kolb, T.E., and Hart, S.C. Tree physiological response to groundwater depth: influence of
species and river flow regulation. Ecological Applications (in review)
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Horton, J.L., Kolb, I.E., and Hart, S.C. Leaf gas exchange characteristics differ among Sonoran Desert
riparian tree species. Tree Physiology (in review)
Horton, J.L., Kolb, I.E., and Hart, S.C. Patterns of riparian tree physiology and growth during dry and wet
years, (in preparation)
Horton, J.L., Kolb, T.E., and Hart, S.C. Environmental water sources used by Sonoran Desert riparian trees
along gradients of ground water availability, (in preparation)
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U915545
BIODIVERSITY OF MINNESOTA CADDISFLIES (INSECTA: TRICHOPTERA)
David C. Houghton
University of Minnesota
Objectives/Hypotheses: This research has main four objectives: 1) inventory the caddisflies (Insecta:
Trichopterd) of Minnesota, ascertain the distribution of all species, and group these distributions into overall
biologically-meaningful patterns; 2) determine large-scale environmental variables (e.g., habitat, glacial
retreat patterns) potentially important to influencing determined patterns; 3) correlate site-specific variables
(e.g., pH, stream order) with individual species distributions; and 4) Develop keys to species identification.
Ultimately, these data will help predict and identify populations of caddisflies both in Minnesota and in the
surrounding states and provinces, which will increase the utility of caddisflies in regional water quality
assessment.
Rationale: Pollution of lakes and streams is one of the largest environmental problems currently facing both
Minnesota and much of the United States. Quantifying the composition of aquatic invertebrate assemblages,
such as those of caddisflies, is a powerful technique for evaluating aquatic pollution because it directly
measures ecosystem functioning. The largest weakness of this technique is the current lack of taxonomic,
distribution, and ecological data for aquatic invertebrates. Without these data, prediction of the characteristic
organisms of particular ecosystems is difficult and only broad pollution assessments can be made.
There have been no comprehensive taxonomic studies of the caddisflies of Minnesota, or of any of its
adjacent states and Canadian provinces. There has been no significant effort to document the statewide
distribution of the known Minnesota species or to correlate regional distributions with watershed conditions.
Minnesota is an ecologically diverse state, situated at the intersection of the three largest biotic provinces
of North America: Prairie, Deciduous Forest, and Coniferous Forest. The ecological diversity of the state
suggests a diverse fauna with strong affinities to faunas of neighboring states and provinces. An inventory
and analysis of the Minnesota caddisflies may, therefore, have important regional utility for water quality
assessment.
Approach; My approach is to characterize the distributions of Minnesota caddisflies within each of the
state's 81 watersheds. Treating the watershed as a collecting unit should resolve important spatial differ-
ences in the fauna without being effort prohibitive. Analysis of distributions will be made using Detrended
Correspondence Analysis, a multivariate ordination procedure that produces a cluster plot of watersheds in
"species-space" and distills the complex variation inherent in large data sets into one or two biologically
meaningful axes. Correlating these axis scores with environmental data (e.g., habitat, glacial retreat patterns)
using Spearmen Rank Correlation will suggest variables important for influencing distribution patterns
within the Minnesota caddisfly biodiversity.
Status; I have had one field season and am currently inputting these specimens as well as historical records
into the database. At present, the database contains 56,101 caddisfly specimens representing 290 species.
These are from 1,331 collections from 431 localities throughout the state made between 1897 and 1999. I
also have approximately 250 literature records. The objective of the upcoming field season is to collect in
areas under-represented by previous collecting as part of the overall goal of statewide representative
sampling.
Papers & Publications: None at this time.
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U915440
IMPROVING PEST MANAGEMENT BY UNDERSTANDING
MOVEMENT BEHAVIOR
Cynthia L.Hsu
Cornell University
Objectives/Hypotheses; To understand the movement behavior of the adult and larval stages of an apple
pest, the obliquebanded leafroller, Choristoneura rosaceana. Information on adult movement will be used
to assess the potential for the spread of insecticide resistance between orchards. Larval movement data will
be used to improve the ability of current monitoring methods to predict fruit damage, and to maximize the
effectiveness of current control methods.
Rationale; Understanding the ecology and behavior of insect pests can facilitate the development and
improve the effectiveness of pest management options. One relatively difficult and, therefore, understudied
aspect of insect ecology is movement behavior, yet the movement of individuals and populations between
crops and within a crop is a key component of pest/crop dynamics. Movement behavior can affect the spread
of insecticide resistance, the effectiveness of control methods, and the timing and rate of colonization of a
crop. My research is focused on studying the movement behavior of an apple pest, the obliquebanded
leafroller, Choristoneura rosaceana (Harris).
Approach: Field-based studies of the movement of adult leafrollers in an orchard using mark-recapture
methods and behavioral observations were conducted last year and will be repeated this year. This data will
be analyzed and compared with predictions generated by an individual-based movementmodel to determine
whether the movement patterns are random or have a directional component Empirical data from
field-studies will also be compared with results from a spatial analysis of 6 years of leafroller damage
records for orchards along the southern bank of Lake Ontario, NY. Additional mark-recapture and
observational field work will be done this season to understand larval movement within a tree. Data will be
collected to determine when the larvae are most active, whether their movement is directional, and how far
and how often they move.
Status; Field research conducted during summer 1999 showed that adult female leafrollers could move
more than 200 feet within 6 days. Preliminary analyses indicated that their movement was correlated with
wind direction. These experiments will be repeated in summer 2000. An individual-based simulation model
was developed during spring 2000. Dispersion patterns from simulations assuming random movement and
assuming directional movement based on wind direction will be compared with field results from the
summer 1999 and 2000 mark-recapture experiments. Laboratory trials with larvae on fava beans indicated
that it takes between 1-3 hours for the larvae to form a leaf curl, and between 2-4 hours before they began
to feed within the curl. None of the larvae had moved from their leaf curls after 24 hours. This work will
be conducted in the apple orchard during summer 2000 for longer observation periods.
Papers & Publications: None at this time.
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U915541
ENVIRONMENTAL ANTIBIOTICS IN CHESAPEAKE BAY TRIBUTARIES
Thomas B. Huff
George Mason University
Ob j ectives/Hvpotheses: Environmental antibiotics could be affecting the ecology of the Chesapeake Bay
and its tributaries. The goal of this research is to determine the presence and concentration of antibiotics in
the Chesapeake Bay watershed.
Rationale: The use of pharmaceutical compounds in the extensive animal feedlot operations (AFOs) on the
Delmarva Peninsula could introduce antibiotics into the Chesapeake Bay and its tributaries through runoff.
The presence of environmental antibiotics may be disrupting the microbial ecology of these waterways. They
may also be producing strains of microorganisms that have developed resistance to these drugs. This has
profound implications for human health. Analytical methods must be developed to determine trace-level
concentrations of antibiotics in environmental samples.
Approach; This study will develop methods for determining antibiotic concentrations in surface waters and
sediment. It will coincide with a microbial study wherein native bacteria will be extracted from sediments
and tested for resistance or sensitivity to the antibiotics that have been approved for agricultural use. The
resistance study will help target specific antibiotics for method development.
Status; Preliminary samples have been obtained, and resistance to several antibiotics has been noted.
Analytical methods for the detection of trace-levels of these suspected environmental antibiotics are
currently in development.
Papers & Publications: Isbister, J., Huff, T.B., Simon, N.S., and Tu, T. 1999. Ecological effects of
antibiotics in runoff from an eastern shore tributary of the Chesapeake Bay. Conference Proceedings:
Effects of Animal Feeding Operations (AFOs) on Water Resources and the Environment. Fort Collins, CO.
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U915358
DAMAGE TO ARACHIDONIC ACID AND PLASMID DNA MEDIATED
BY PRODUCTS OF MMT COMBUSTION
Rachel A. Jameton
University of Utah
Objectives/Hypotheses: The aim of this study is to determine if products of combustion of MMT damage
biomolecules such as lipids and plasmid DNA.
Rationale: Methylcyclopentadienyl manganese tricarbonyl (MMT) was developed by Ethyl Corporation
as an octane enhancer. The addition of 33 mg to each liter of gasoline raises the octane number, (R + M)/2,
by about 0.6 units.1 The introduction of MMT has led to debate over potential deleterious effects of excess
manganese in the environment. Proponents of the additive argue that manganese is an essential trace
element, and that excess is usually excreted by healthy adults.2 Opponents contend that airborne manganese
can lead to bronchitis, pneumonia and asthma.1 Neurodegeneration4, teratogenesis5 and mutagenesis* have
also been linked to over-exposure. While direct exposure to MMT is likely to be minimal, increased
exposure to manganese-containing particles resulting from MMT combustion may be a concern.7
1 Wallington, T.J., Sokolov, O., Hurley, M.D., Tyndall, G.S., Orlando, J.J., Barnes, I., Becker, K.H., and
Vogt, R. Environ Sci Technol 1999;33:4232-4238.
2 Brandt, M. and Schramm, V.L. In: Manganese in Metabolism and Enzyme Function, Schramm, V.L.,
Wedler, F.C., eds. Academic Press: Orlando, 1986.
3 (a) Nogawa, K. Jpn J Pub Hlth 1973;20:315-326; (b) Yiin, S-J. Lin, T-H., and Shih, T-S. Scand J Work
Environ Htth 1996;22:381-386.
4 For example: (a) Lloyd, R.V. Chem Res Toxicol 1995;8:111-116; (b) Shen, X-M., and Dryhurst, G.
Chem Res Toxicol 1998;7:824-837.
5 Treinen, K.A., Gray, T.J.B., and Blazak, W.F. Teratology 1995;52:109-115.
6 Gallez, B., Baudelet, C., Adline, J., Geurts, M., and Delzenne, N. Chem Res Toxicol 1997;10:360-363.
7 Zayed, J., Hong, B., and L'Esperence, G. Environ Sci Technol 1999;33:3341-3346.
Approach; Several products of combustion of MMT were applied to pUC 19 plasmid DNA and arachidonic
acid (a model lipid) alone and in the presence of the environmentally available oxidant system, sulfite/
oxygen. The manganese complexes are: Mn(II)chIoride, Mn(III)phosphate, Mn(II)chloride, Mn(III)phos-
phate, Mn(II)pyrophosphate, Mn(III)pyrophosphate, Mn(Il)pyrophosphate and Mn(III)pyrophosphate,
Mn(II)sulfate, Mn(Il)oxide, Mn(II,III)oxide, and Mn(IV)oxide.
Status; (a) pUC19 Plasmid DNA-Damage to plasmid DNA mediated by manganese complexes was
observed in the presence of sulfite/oxygen, an environmentally available oxidant system. This may occur
by the autoxidation of sulfite in the presence of manganese. The manganese complexes, alone, did not affect
the DNA. (b) Arachidonic Acid-Manganese oxides were found to degrade the model lipid, arachidonic acid.
Detection of one of the products of lipid degradation, malondiatdehyde, by thiobarbituric acid, indicates a
possible radical pathway for the damage observed.
Papers & Publications; None at this time.
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U915653
DEVELOPMENT OF THE ASCIDIAN, CIONA SAVIGNYI, AS A MARINE
ECOLOGICAL INDICATOR ORGANISM
David S. Johnson
Stanford University
Objectives/Hvpotheses; We hope to develop cutting-edge genetic and developmental techniques to study
the effects of environmental stress (anthropogenic or otherwise) on the ascidian, dona savignyi. We are
interested in the basic biology of stress response as well as the potential of such knowledge for ecological
monitoring.
Rationale; Ciona savignyi is a common inhabitant of nearshore marine ecosystems in California. It is found
in impacted ecosystems as well as more pristine ones. As filter feeders, ascidians are constantly exposed
to toxins found in the water. Therefore, we assume that ascidians have evolved a host of molecular defenses
to prevent these toxins from causing damage. Furthermore, Ciona savignyi is an excellent model organism,
as it is easy to culture in the laboratory and has a compact and efficient genome. A host of embryonic
manipulations are also possible, including cell ablation, lineage tracing, and ectopic gene expression. Thus,
Ciona savignyi is advantageous in its local abundance, ecological significance, and potential for laboratory
manipulation.
Approach; Our first major goal will be to develop cDNA microarray technology for Ciona savignyi. We
will first need to design cDNA libraries for animals at various developmental stages. Then, expressed
sequence tag (EST) sequencing will characterize the clones and decrease repetition. We assume that the EST
sequencing will identify clones for genes that are known to function in physiological defense, such as the
multidrug resistance (MDR) and cytochrome p450 gene families. Once we have developed the cDNA
microarrays, it will be possible to compare differential mRNA expression caused by exposure to toxins (in
both environmental and laboratory animals). It will also be possible to examine the ability of the animals
to induce this stress response at various stages of development.
Status; We are currently developing "tailbud stage" cDNA libraries and sequencing ESTs from these
libraries. Concurrently, we are developing TaqMan quantitative PCR techniques for message quantification
and (later) microarray verification.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915168
RAPID CHARACTERIZATION OF LONG-TERM HOC DESORPTION FROM SOILS
AND SEDIMENTS BY SUPERHEATED WATER EXTRACTION TECHNIQUES
Martin D. Johnson
University of Michigan
Objectives/Hypotheses; The goal of this research is to develop a superheated water extraction metho-
dology to rapidly characterize the long-term desorption of hydrophobic organic contaminants from soils and
sediments.
Rationale; Hydrophobic organic contaminants (HOCs) in subsurface systems have been a major
environmental concern over the past several decades, and assessing their mobility and bioavailability has
been the focus of many research efforts in recent years. Subsurface HOCs can strongly sorb to soils and
sediments and then slowly desorb for years into interstitial water at low, but toxic, concentrations. Thus, in
order to accurately predict associated risk and plan effective remediation strategies, HOC desorption
processes must be understood in a predictable manner. A technique for rapidly predicting the long-term
HOC desorption behavior in a contaminated soil or sediment would be invaluable for engineers and scientists
planning remediation schemes and/or grappling with difficult alternative remediation endpoint decisions.
Approach: Liquid-phase temperature programmed desorption (TPD) experiments were conducted to
determine the apparent activation energies of phenanthrene desorption from contaminated soils and
sediments. Apparent desorption energies were confirmed by Arrhenius modeling of isothermal desorption
rates at temperatures between 25 and 150° C. Phenanthrene desorption rates and extents were also measured
at 25° C for the corresponding contaminated geosorbents for up to 455 days.
Status; Superheated water extraction and liquid-phase TPD have proven to be effective techniques for
rapidly characterizing long-term phenanthrene desorption from soils and sediments. The research goals are
met, and two papers are being submitted for publication.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915140
INFLUENCE OF BIOSURFACTANTS ON SOIL-AGED ORGANIC
CONTAMINANT TRANSPORT
Stephanie E. Johnson
University of Virginia
Objectives/Hypotheses; This research will investigate and quantify the influence of microbially produced
biosurfactants on the release and transport of organic contaminants (specifically, phenanthrene and atrazine)
from soils and model sorbents after these contaminants have aged on the soils/sorbents for times ranging
from 1 week to 9 months.
Rationale; Historically, contaminated sites include a large contaminant fraction that is less available to
desorption and biodegradation due to the aging of the chemicals on soil. Continued research is necessary
to define the role of contaminant aging either as a beneficial outcome of natural soil processes that reduce
contaminant transport to deeper groundwater systems or as a long-term reservoir for contaminants awaiting
degradation or release by slow desorption or microbial activity. Most aged-contaminant desorption studies
are conducted under abiotic, chemically simplistic conditions; yet, the influence of microorganisms on the
fate of aged contaminants is poorly understood and critical to assessing the threat of our nation's con-
taminated soils.
Approach; Radiolabeled atrazine and phenanthrene will be applied separately to a series of model sorbents
and sterile soil and aged for 7, 45, and 270 days under saturated conditions. The model sorbents—XAD
resins—were selected to represent an idealized microporous soil with hydrophobic pore walls and known
pore sizes. The soil selected is an organic-rich silt-loam. At the end of each aging period, three 2.5x15 cm
columns will be constructed using each of the contaminant-aged sorbents, with the sorbents packed in the
column as a dense slurry. The columns will then be flushed at a slow flow rate with contaminant-free
artificial soil water and biosurfactant—one column at a concentration below the critical micelle concen-
tration, a second column with greater than cmc biosurfactant, and a third biosurfactant-free column as the
control. Columns will be run for a period of approximately 2 weeks, and all columns will be maintained
under sterile conditions with addition of sodium azide to the influent. Filtered and unfiltered outflow
samples will be analyzed on the liquid scintillation counter. Biosurfactant concentrations will also be
measured periodically in the outflow samples with a surface tensiometer. A bromide tracer pulse will be
used to quantify the hydraulic parameters of each column. The breakthrough column data will be analyzed
using a distributed mass-transfer rate model (Culver et al., 1997).
A series of supporting batch experiments will also be performed to determine equilibrium sorption isotherms
for both atrazine and phenanthrene on the soil and sorbents selected. Similar equilibrium sorption
experiments with biosurfactant added will be required to assess the changing solubility of the contaminants
with changing surfactant concentration. These sorption experiments will also be used to determine the
appropriate biosurfactant input concentrations for the column experiments.
Status; Experimental work is ongoing. I expect to defend my dissertation in the spring of 2001.
Papers & Publications; Johnson, S.E., Herman, J.S., Mills, A.L., and Hornberger, G.M. 1999. Bio-
availability and desorption characteristics of aged, nonextractable atrazine in soil. Environ Toxicol Chem
18:1747-1754.
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U915543
BEHAVIORAL AND ECOLOGICAL INTERACTIONS OF RAPTORS
AND LEMURS: A MULTIPLE PREDATOR-MULTD7LE PREY APPROACH
Sarah M. Karpanty
State University of New York, Stony Brook
Objectives/Hypotheses: Understanding the ecology and behavior of raptors is important as evidence
suggests that they function as keystone species in ecosystems by controlling population levels of prey species
and serving as sensitive indicators of environmental change and habitat quality. Recently, there has been
increased demand for knowledge regarding the ecology and behavior of Malagasy raptors, both by
conservation biologists in-terested in preserving the ecosystems of Madagascar and primatologists seeking
to understand the historic and present-day selection pressures on lemur life-history characteristics. Direct
observations of predation on primates are rare, yet predation is hypothesized as a significant force in primate
evolution. Estimates of present day predation rates are needed to solve this problem. Lemurs appear to face
both terrestrial and aerial predators in most of their natural habitats; thus, they offer an excellent system in
which to study the effects of multiple predators on antipredator strategies and population dynamics. This
study has practical conservation importance as research suggests that the removal or introduction of
predators may affect both the demography and behavior of prey species. The following hypotheses will be
addressed: 1) predation by large, diurnal raptors represents a significant source of mortality for lemur
populations; 2) predation risk of lemurs to raptors varies seasonally with peaks during lemur birth and raptor
nesting seasons; 3) lemurs have specific antipredation tactics against the large diurnal raptors; 4) there is a
trade-off in antipredator behaviors of lemurs exposed to a multiple predator system leading to enhancement
or reduction of risk; and 5) predation risk and response are correlated with group size, activity patterns, and
body size in lemurs.
Rationale; (Not received at time of printing.)
Approach; Nesting, feeding, and ranging behaviors of the Henst's Goshawk, Accipiterhenstii, Madagascar
Harrier-Hawk, Polyboroides radiatus, Madagascar Buzzard, Buteo brachypterus, and Madagascar
Serpent-Eagle, Eutriorchis astur, will be studied at Ranomafana National Park in the eastern rainforests of
Madagascar. Raptor prey profiles will be constructed and correlated with demographic patterns of both
predator and prey to quantify the rate and risk of raptor predation on lemurs. The behavioral and
demographic response of lemurs exposed to a multiple predator community will be examined both
experimentally and theoretically. Diurnal (Propithecus d. edwardsi, Varecia v. variegatd), cathemeral
(Hapalemursp., Eulemursp.), and nocturnal (A vahi laniger) lemurs will be experimentally exposed to model
ground and aerial predators to examine the behavioral responsesof lemurs in a multiple-predator community.
Studies will be conducted continuously over a 2-year period in order to examine temporal variation in the
predator-prey interactions of raptors and lemurs in Ranomafana National Park.
Status; (Not received at time of printing.)
Papers & Publications; Karpanty, S.M. and Goodman, S.M. 1999. Diet of the Madagascar Harrier-Hawk,
Polyboroides radiatus, in southeastern Madagascar. Journal of Raptor Research. 33(4):313-316.
Karpanty, S.M. and Grella, R. Lemur responses to diurnal raptor vocalizations in the eastern rain forests of
Madagascar. Folia Primatologica (submitted)
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Karpanty, S.M. and Grella, R. Discovery of the Madagascar Serpent-Eagle, Eutriorchis astur, in central-
and southeastern Madagascar. Bird Conservation International (submitted)
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U915357
EFFECTS OF FLUVIAL DISTURBANCE AND FLOW REGULATION
ON GREAT PLAINS RIPARIAN TREES
Gabrielle L. Katz
University of Colorado
Objectives/Hypotheses; The goals of this project are to examine the downstream effects of dams on
riparian forests in the southern Great Plains, and to determine the ecological factors contributing to the
invasive success of the exotic Russian olive (Elaeagnus angustifolid) in these ecosystems.
Rationale; Two of the most important human impacts affecting riparian ecosystems in the western United
States are hydrologic alterations and biological invasions. In the southern Great Plains, native riparian for-
ests are dominated primarily by plains cottonwood (Populus delloides subsp. monilifera), a pioneer species
that depends on fluvial disturbance for recruitment. On many rivers, cottonwood recruitment has been
curtailed downstream of dams where reduced flow variability has resulted in a lack of suitable establishment
sites. In these settings, the exotic Russian olive is often successful, suggesting that it depends less on
dynam ic fluvial processes for recruitment. By elucidating the effects of flow regulation on native and exotic
riparian trees, this research will provide information for river management and conservation, and will also
contribute to a more general theoretical understanding of biological invasions.
Approach; This project is designed as a multi-scale analysis. At the landscape scale, I compare the riparian
forest along three river reaches in eastern Colorado, USA—the unregulated Arikaree River, and the regulated
S. Fork Republican River both upstream and downstream of Bonny Dam. At the stand scale, I examine the
composition, population age structure, and geomorphic distribution of the floodplain forest at three sites
within each of the three study reaches. At the micro-scale, I use manipulative field experiments to inves-
tigate the influence of physical disturbance and granivory on seedling establishment of Russian olive and
plains cottonwood, and I examine the distribution of seedlings of these two species at the nine field sites.
Status; Field data collection and experiments are complete. I am currently analyzing the eastern Colorado
data.
Papers & Publications; Katz, G.L., Friedman, J.M., and Beatty, S.W. Effects of physical disturbance and
granivory on establishment of native and exotic riparian trees, (in preparation)
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U915344
INTEGRATING COMPETITION AND PREDATION: CONSERVATION IMPLICATIONS
OF MULTI-SPECIES INTERACTIONS AT THE LANDSCAPE SCALE
Todd E. Katzner
Arizona State University
Objectives/Hvpotheses; To develop an understanding of the driving forces behind community structure
in a unique mixed species assemblage of top predators, and to apply this ecological theory towards con-
servation.
Rationale; (Not received at time of printing.)
Approach; Competition and predation are generally seen as two of the most important evolutionary
processes that shape community structure and population dynamics. However, they have historically been
studied as separate entities, and their interaction has not been investigated rigorously among terrestrial
vertebrates. As a consequence, conservation biology has been slow to embrace the relevance of these
processes, focusing on them only when they involve the effects of introduced or alien species. Recent
ecological studies in aquatic systems indicate that multiple trophic interactions play important roles in
structuring communities. Therefore, research focused on the simultaneous effects of competition and
predation in a terrestrial vertebrate system has great potential to advance our understanding of community
ecology and provide important insight into conservation of interacting threatened species.
This research investigates these processes in a unique community of four generalist eagle species at the
Naurzum Zapovednik, a protected nature reserve in north-central Kazakstan. Specifically, I am determining
the interactions that drive predator community structure and, subsequently, how these interactions are
influenced by human-induced landscape changes. The system is well suited to this investigation because the
eagle community and their interactions across multiple trophic levels can be easily monitored in this
landscape.
Landsat satellite images and Digital Elevation Models (OEMs) of the vegetative and landform components
of the Zapovednik will be incorporated into Geographic Information System (CIS) maps. Data collection
includes monitoring of eagle and prey demographic trends, relating eagle habitat and diet to prey population
densities, and identification of the role each individual eagle plays in impacting higher-order trends. All data
collected will be spatially referenced with a Global Positioning Satellite (GPS) receiver for creation of
organism-driven map overlays to identify correlations between landscape features, human interference, and
animal behavior. Finally, I will integrate these data and use models to further explore the relative strength
of the relevant ecological processes and their interaction on individual behavior, population dynamics, and
community structure in this heavily altered environment. In addition to investigation of a topical question
in community ecology, this work has direct conservation implications because it will allow formulation of
specific management recommendations based on ecological theory.
Status; (Not received at time of printing.)
Papers & Publications; Katzner, T.E., Knick, S.T., Bragin, E.A., Katzner, D.W., and Smith, A.T. 1999.
Understanding relationships among raptors: alternative numerical and graphical approaches to diet analysis.
1999 Annual Meeting, Raptor Research Foundation, La Paz, Mexico.
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Katzner, I.E., Knick, ST., Bragin, E.A., Katzner, D.W., and Smith, A.T. 1999. Alternative approaches to
analysis of diets of raptors. 3rd Eurasian Conference of the Raptor Research Foundation, Mikulov na Morav,
The Czech Republic.
Katzner, I.E., Bragin, E.A., Knick, S.T., and Smith, A.T. 1998. Nest spacing and diet selection in a unique
multi-species community of eagles in central Asia. 1998 Annual Meeting, Raptor Research Foundation,
Ogden, UT.
Knick, S.T., Bragina, T.M., Bragin, E.A., and Katzner, T.E. 1999. Classification of a forest and steppe
region in northern Kazakstan from Landsat thematic imagery. International Wildlife Conference, Godollo,
Hungary. Poster presentation.
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U915351
INDUCED SEQUESTRATION OF PHENOLIC COMPOUNDS IN NATURAL SORBENTS
Michael Keinath
University of Michigan
Objectives/Hypotheses; To evaluate the effects of metal oxide induced coupling reactions of phenolic
compounds on sorption/desorption/sequestration behavior in natural geosorbents. Ultimately this work aims
to evaluate the feasibility of artificially inducing coupling reactions in the subsurface and immobilizing
phenol ics on the soil organic matter.
Rationale; Phenolic compounds are an important class of organic contaminants and are listed among the
25 most frequently detected in groundwater at hazardous waste sites. Often sorption processes dominate the
fate and transport of these chemicals in the subsurface. A significant emphasis has been placed on char-
acterizing sorption onto and desorption from natural sorbents, however, for these same systems, there has
been comparatively little investigation of the coupling reactions that are known to occur with phenolic
compounds and how this coupling affects sorption processes. Theoretically, these coupling reactions can
occtfr between phenolic contaminants and surface functionalities on the soil, forming covalent bonds,
immobilizing the contaminants on the soil matrix. Subsequently, the contaminants would not be subject to
migration, and, therefore, virtually innocuous to the subsurface environment. Additionally they would not
be transported to a water source or surface water interface. Artificially inducing these coupling reactions
could prove to be a novel in situ approach to soil and groundwater remediation that would result in reduced
treatment times and costs.
Approach; The sequestration of phenolic contaminants via abiotic oxidative coupling reactions in the
presence of soils and sediments is being investigated in batch and continuous flow systems. In particular,
the role of birnessite in catalyzing such coupling reactions is being determined. Birnessite is one of the most
predominant naturally occurring manganese(III/IV) oxide minerals in soil environments. The first phase
investigated the oxidative coupling phenomena with soil-free birnessite-phenol batch systems. This phase
allowed for the quantification and characterization of both phenolic monomer disappearance and polymer
formation as a function of time, initial phenol concentrations and catalyst activity (birnessite concentration).
The second phase of the study investigated the efficacy of birnessite-catalyzed phenolic polymer formation
to induce sequestration in natural sorbent materials. This was accomplished using non-equilibrium sorption
flow-through column systems of natural sorbents and birnessite amendments, where sequestration was
operationally measured as the degree of non-extractability. Two different systems were analyzed: a) glass
bead packed columns with variable doses of birnessite (delta-MnO2), that were used to evaluate the
extractability of coupling products in the absence of cross-coupling, and b) soil packed columns with
variable doses of birnessite, to evaluate coupling in simulated subsurface conditions. Short glass columns
were packed with glass beads or three different soil types: a surface soil Fox Forest, the diagenetically older
Lachine shale and the diagenetically young Canadian Peat and varying birnessite doses.
Status; (Not received at time of printing.)
Papers & Publications; None at this time.
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U915239
SEDIMENT ENTRAINMENT AND STREAM BENTHIC COMMUNITIES: IMPLICATIONS
FOR FRESHWATER BIOASSESSMENT
Stephen T. Kenworthy
Johns Hopkins University
Objectives/Hypotheses; The goal of this project is to document how the spatial and temporal characteristics
of sediment disturbance influence the composition of benthic invertebrate communities in streams. The
intensity of sediment entrainment and transport will be related to changes in the relative abundance of
benthic macroinvertebrate taxa. This information will be used to evaluate the influence of sediment dynamics
on stream benthos in different fluvial settings, and to infer likely biological responses to changes in
watershed hydrology and sediment loading.
Rationale; Watershed monitoring programs commonly include stream bioassesments based on benthic
macroinvertebrate communities. Because benthic organisms are influenced by both physical and chemical
factors, there is a need to distinguish between these effects in order to properly interpret biological data and
to guide restoration activities. By demonstrating relationships between sediment dynamics and stream
benthos, this research will complement existing protocols for physical habitat assessment and strengthen the
scientific basis of benthic biomonitoring programs.
Approach; The research includes experimental investigation of the effects of sediment entrainment and
transport on benthic organisms and simulation of sediment disturbance and benthic community dynamics
in settings that differ in hydrologic and bed material characteristics.
The experimental work involves treatment of aquatic insect populations with flow and substrate disturbances
of varying intensity in an artificial stream. The composition of experimental sediment beds is designed to
replicate gravel-bed river surface structure. Selection of organisms is based on behavioral and physical
characteristics expected to produce differential responses to substrate disturbance. The degree of sediment
entrainment and transport is carefully controlled, and the resulting washout and mortality of benthic
organisms is measured.
Simulation of disturbance-response dynamics will utilize the results of the laboratory work to explore the
influence of hydrologic regime, river bed topography, and substrate composition on the spatial pattern and
taxonomic structure of benthic communities in gravel-bed channels.
Status; Experiments are underway.
Papers & Publications; None at this time.
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U915624
CONTROLS ON ARSENIC MOBILITY IN A METAL-CONTAMINATED WETLAND
Nicole E. Keon
Massachusetts Institute of Technology
Objectives/Hypotheses: The objective of this work is to identify and examine the processes affecting
arsenic immobility in wetland sediments. Both large- and small-scale arsenic immobilization mechanisms
will be investigated. We hypothesize that oxidizing near-root microzones produced by wetland plant roots
may enhance the ability of wetland sediments to sequester arsenic, rendering the arsenic relatively immobile
in this environment.
Rationale; Arsenic is currently ranked first on the ATSDR priority list of hazardous substances based on
toxicity, distribution frequency, and human exposure potential. The mobility of arsenic in soils and
sediments affects the management of many Superfund sites, including the Wells G & H wetland of Woburn,
Massachusetts, the location of this study. Biogeochemical processes that can either enhance or reduce
arsenic sequestration into the solid phase, thereby limiting mobility in groundwater, often determine the fate
of arsenic. To characterize the arsenic-bearing solid phases, we have verified a sequential extraction method
that is cost-effective and accessible. We will also investigate the impact of the near-root oxidizing
environment on binding arsenic.
Approach: Geochemical processes of mineral precipitation and adsorption in the soil will be investigated
to determine the relative significance of these pools. Sequential extractions will enable the differentiation
of arsenic-bearing phases, including weakly and strongly adsorbed, co-precipitated with amorphous and
crystalline metal oxides, and precipitated as sulfide phases. Sediment iron and arsenic speciation and mineral
identification will also be determined by x-ray spectroscopic techniques. In the wetland plant root zone, the
magnitude and effects of root oxygenation on iron and arsenic geochemistry will be investigated. A
combination of selective chemical extractions and microanalytical methods including electron microprobe
analysis and secondary ion mass spectrometry will be applied.
Status: To date, we have successfully developed and tested a sequential extraction method for evaluating
arsenic binding in sediments, using known arsenic solid phases. The next segment of this work is to
investigate the role of the wetland plants in creating oxic microzones in otherwise reducing wetland
sediments. I plan to complete this research in the next 2 years.
Papers & Publications; Keon, N., Swartz, C.H., Brabander, D.J., Harvey, C., and Hemond, H.F. 1999.
Evidence for predominantly adsorbed arsenic in a wetland sediment. EOS Trans. Amer Geophys Union
80(17):S147.
Brabander, D.J., Keon, N., Stanley, R.H.R., and Hemond, H.F. 1999. Intra-ring variability of Cr, As, Cd,
and Pb in red oak revealed by secondary ion mass spectrometry. PNAS 96:14635-14640.
Keon, N., Brabander, D.J., Stanley, R.H.R., and Hemond, H.F. 1998. Sequestration of toxic metals in
urban wetland. EOS Trans. Amer Geophys Union 79(17):S137.
an
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U915630
MICROBIAL POPULATION DYNAMICS DURING THE DEGRADATION
OF COMPLEX CONTAMINANT MIXTURES
Eric A. Kern
Montana State University
Objectives/Hypotheses: The objective of my research is to understand how chemical and physical factors
governing the interaction of contaminants in the soil microenvironment affect the selection of contaminant-
degrading microorganisms.
Rationale: Spills of contaminants such as hydrocarbons or chlorinated solvents result in the introduction
complex mixtures of contaminants to an environment. Many of these contaminants are characterized by low
water solubilities and high Koc values and rapidly undergo chemical sorption and physical sequestration
within soil organic matter, which renders contaminants less available to degradation by microorganisms.
Approach; To simulate contaminant microenvironments present following a spill in a soil environment,
mixtures were selected in which nonaqueous phase liquid (NAPL) phases and solid phases (e.g., soil organic
matter) were important phases controlling contaminant availability. Batch soil reactors and liquid enrich-
ments were amended with various mixtures of hydrocarbons, ranging from extremely complex mixtures
(crude oil) to enrichment on only single hydrocarbon substrates. The soil batch reactors and liquid
enrichment cultures were sampled regularly for both chemical analysis (GC/MS) of the contaminant mix-
tures and molecular analysis of the degradative microbial communities. Denaturing gradient gel
etectrophoresis (DGGE) separation of a PCR-amplified 322 bp 16S rDNA fragment is used to provide a
cultivation-independentapproachtodetermining the structure of the microbial communities through the time
course of degradation.
Status: Anticipated date of graduation is summer 2001.
Papers & Publications; Kern, E.A., Inskeep, W.P., and Ward, D.M. Molecular evidence for ecological
succession during the microbial degradation of crude oil and synthetic hydrocarbon mixtures, (in
preparation)
Veeh, R.H., Kern, E.A., Langner, H.W., Macur, R.E., and Cunningham, A.B. Enrichment and molecular
characterization of methyl tert-butyl ether (MTBE)-degrading bacteria from a gasoline-contaminated
aquifer, (in preparation)
Veeh, R.H. and Kern, E.A. Enrichment and isolation of MTBE-degrading bacteria from a Montana gasoline
release site, (review article for Underground Tank Technology Update, submitted)
Kern, E.A., Ferris, M.J., and Ward, D.M. Purification of bands in denaturing gradient gel electrophoresis
(DGGE) profiles for nucleotide sequence analysis, (in review)
Friedrich, M., Grosser, R.G., Kern, E.A., Inskeep, W.P., and Ward, D.M. 2000. Effect of model sorptive
phases on phenanthrene biodegradation: molecular analyses of enrichments and isolates suggests selection
based on bioavailability. Applied and Environ Microbiol (in press)
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U915144
CLIMATE-MEDIATED SHIFTS IN HURRICANE CHARACTERISTICS:
LARGE-SCALE ECOLOGICAL EFFECTS ON CORAL REEFS
Alexander M. Kerr
Yale University
Objectives/Hypotheses; To begin understanding potential climate-induced shifts in storm disturbance to
marine ecosystems, I propose to examine the role of wave disturbance in maintaining oceanic-basin-wide
patterns of ecological diversity in scleractinian corals in the western Pacific Ocean, a region experiencing
the widest range of return times of cyclonic storms in the world. I ask: 1) What is the relationship between
hurricane features (intensity, frequency and temporal spacing) and the population demographics of corals
with contrasting expected responses to disturbance? 2) What is the contribution of factors (depth, colony
size, colony shape, reef aspect to swell, recovery time) mediating this interaction?
Rationale: Concern over future trace-gas-induced global warming has recently motivated an understanding
of the ecological effects of changes in climate. Severe cyclonic storms (hurricanes, cyclones, and typhoons)
are an important source of disruption to coral reefs and whose destructive potential appears correlated with
global climate. What has been and what potentially will be the effects of altered storm regimes on coral reefs
and, subsequently, on those who depend upon this resource? The lack of data is profound. While the dia-
meter of gale-force winds in a cyclonic storm often extends over a 100 kilometers and clines in the frequency
and intensity of such storms span oceanic basins, ecological studies invariably monitor local to islandwide
effects, often of single storms. After 13 years, David Stoddart's appeal for systematic, multiscale investi-
gations of hurricane effects remains unanswered.
Approach; First, I will develop a time-integrated picture of shallow-water significant wave characteristics
for any given reef, incorporating the effects of bathymetry, shoaling and refraction on deepwater waves
estimated from 50 years of archived meteorological data on cyclonic storms in the western North Pacific.
Much of this involves incorporating standard, previously verified linear wind- and wave-field equations into
a format that allows me to input a site's position and receive, for a given depth, a history of hydrodynamic
attributes responsible for storm damage. Then, I will use the time series to select minimally three islands
experiencing either high, medium, or low wave disturbance and around which I will intensively survey the
population structure of a hemispherical, a tabulate, and an encrusting coral. I will consider several variables
affecting wave-energy transfer, including reef topography, angle of incoming swell, depth, recovery time,
colony size, colony morphology, and storm frequency and intensity. Response variables will include
clustering, percent cover, and number of colonies. The data will be analyzed via multivariate regressions
and path analysis, a method that identifies multilevel synergisms and antagonisms between predictors to
uncover, among other things, their net effect on the variation of the response.
Status: Modeling is completed and preliminary tests using published data on coral populations have begun.
Papers & Publications; Kerr, A.M. 2000. Discussion of Hsu, S.A. and Van, Z. 1998. A note on the
radius of maximum wind for hurricanes. Journal of Coastal Research 16 (in press)
Kerr, A.M. 2000. Defoliation of an island (Guam, Mariana Archipelago, Western Pacific Ocean) following
a saltspray-laden "dry" typhoon. J Tropical Ecol 16 (in press)
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U915597
URBAN BY NATURE: SHAPING SEATTLE'S
METROPOLITAN ENVIRONMENTS, 1880-1970
Matthew W. Klingle
University of Washington
Objectives/Hypotheses; This project investigates the built and natural environments as integrated features of
the city, focusing on the cultural, social, and material factors that reshaped the appearance, functions, and
meanings of key Seattle landscapes. My dissertation asks two questions: To what extent did science,
technology, and planning affect Seattle's aquatic and terrestrial ecosystems as well as the human communities
that depended upon them? And how did Seattle's changing landscape shape residents' perceptions of
environmental quality and urban living? I argue that changes in Seattle's built and natural environments
challenge prevailing notions that Americans came to see the city as something separate from nature during the
twentieth century. My hypothesis is that physical labor, technology, and planning simultaneously drew Seattle
residents closer to their local environments while also encouraging their further alienation from nature in the
city.
Rationale: Urbanization has always been an important force in environmental change, but ecologists and
environmental historians seldom studied cities until recently. Understanding how human activities and natural
processes interact over time is important to building habitable cities. But, uncovering material changes is not
enough; understanding the historical context of earlier attitudes toward nature and the power relations that
shaped them is also important. Environmental problems have long histories that require both scientific and
humanistic interpretations. Nowhere is this more important than in determining how to build sustainable and
equitable cities.
Approach; My project unravels the material and cultural history of five different landscapes in Seattle across
a 90-year span: the tidelands and estuaries fronting Elliott Bay, the Lake Washington-Duwamish River
drainage basin, the Cedar River watershed, the earthmoving projects (called regrades) in the city's core, and
the creation of the park and urban forest system. Drawing upon archival material, periodicals, government
documents, and present-day scientific reports from libraries in Boston, Minneapolis/St. Paul, Washington, DC,
and around Puget Sound allows me to analyze the intricacy of landscape change while placing my study in a
larger regional and national context.
Status; I am currently completing research and writing chapters. I will finish my dissertation by early 2001.
Papers & Publications; Klingle, M. 2000. Building Duwamish no. 2: finding and reviving Seattle's wetlands
and waterways. American Society for Environmental History, Tacoma, WA.
Klingle, M. 1999. Pushing back the sea: remaking the human and natural landscapes of Seattle's Lake
Washington watershed, 1890-1945. American Historical Association, Washington, DC.
Klingle, M. 1998. Urban by nature: reinventing Seattle's metropolitan landscape, 1889-1930. Western
Historical Association, Sacramento, CA.
Klingle, M. 1998. Natural by design: the transformation of Seattle's Duwamish River, 1895-1940. Canadian
Historical Association, Ottawa, ON, Canada.
Klingle, M. 1998. Plying atomic waters: Lauren R. Donaldson and the 'Fern Lake concept' of fisheries
management. J History of Biol 31(l):l-32.
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U915210
EFFECTS OF MULTIPLE ENVIRONMENTAL PERTURBATIONS
ON PHYTOPLANKTON COMMUNITIES
Jennifer L. Klug
University of Wisconsin, Madison
Ob i ectives/Hvpotheses; To determine whether the effects of multiple perturbations are predictable given
knowledge of the effects of individual perturbations. To determine whether there are interactions among
perturbations.
Rationale; The ability of ecological communities to maintain and/or resume ecological processes following
perturbation is essential for sustaining all life. The diversity of natural and anthropogenic perturbations
prevents the study of every perturbation individually. Furthermore, many communities are subject to more
than one simultaneous perturbation.
Lakes are particularly suited for investigating the effects of perturbations on communities because
community boundaries are relatively well-defined. In addition, lakes are frequently perturbed due to heavy
human usage and the receipt of substances released throughout the watershed. I am investigating the effects
of changes in two environmental factors (specifically, nutrients and colored dissolved organic matter) on
phytoplankton communities. CDOM is a mixture of organic substances that give brown-water lakes their
characteristic color. CDOM input and nutrient loading are heavily influenced by land use in the watershed;
therefore, human activities such as agriculture, logging, and wetland drainage have large impacts on the
nutrient and CDOM concentrations in lakes.
Approach: I am using a combination of experimental and modeling approaches to investigate the combined
effects of increased nutrients and colored dissolved organic matter (CDOM) on phytoplankton communities.
I used long-term data collected as part of a series of whole-lake experiments to show that increased nutrient
loading and changes in CDOM concentration were responsible for changes in the biomass of particular
groups of phytoplankton (e.g., cyanobacteria and chlorophytes). Changes in CDOM concentration can have
many different effects on phytoplankton, and I have used short-term experiments to look at some of the
mechanisms that may be responsible for the effects of CDOM on phytoplankton biomass. My experiments
showed that one effect of increasing CDOM is negative, caused by CDOM absorbing light which leads to
less light available for photosynthesis. However, CDOM also had a positive effect on phytoplankton
biomass, due to growth stimulation by nutrients present in the CDOM. Given both positive and negative
effects, the challenge is to predict the overall net effect. In my experiments, phytoplankton biomass in-
creased in response to increased CDOM concentration, suggesting that the positive effect due to nutrients
present in the CDOM outweighed the negative effect of decreased light availability. In addition, the results
from my experiments show that changes in CDOM and nutrient input may alter the interactions between
phytoplankton and bacteria such that bacterial uptake of phosphorus becomes a major driver of phyto-
plankton growth.
Status; I have completed all of my field work and am currently working on writing my dissertation. I will
be graduating in December 2000.
Papers & Publications; Klug, J.L., Fischer, J.M., Ives, A.R., and Dennis, B. 2000. Compensatory dy-
namics in planktonic community responses to acidification. Ecol 81:387-398.
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Klug, J.L. and Fischer, J.M. 2000. Factors influencing the growth of Mougeotia in experimentally acidified
mesocosms. Canadian Journal of Fisheries and Aquatic Science (in press)
Fischer, J.M., Klug, J.L., Reed-Andersen, T., and Chalmers, A. 2000. Vegetation pattern in a southeastern
salt marsh: the role of disturbance and the importance of scale. Estuaries (in press)
Ives, A.R., Klug, J.L., and Gross, K. 2000. Stability and species richness in complex communities. Ecology
Letters (in press)
Ives, A.R., Gross, K.G., and Klug, J.L. 1999. Stability and variability in competitive communities Sci
286:542-544.
Micheli, F., Cottingham, K.L., Bascompte, J., Bjornstad, O.N., Eckert, G.L., Fischer, J.M., Keitt, T.H.,
Kendall, B.E., Klug, J.L., and Rusak, J.A. 1999. The dual nature of community variability Oikos
85:161-169.
Ives, A.R., Foufopoulos, J., Klopfer, E.D., Klug, J.L., and Palmer, T.M. 1996. Bottle or big-scale studies:
how do we do ecology? Ecol 77(6):681-685.
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STAR Graduate Fellowship Conference
U915365
REDUCTION OF HERBICIDES IN WETLAND SEDIMENTS
Theodore P. Klupinski
The Ohio State University
Objectives/Hypotheses; This research project is designed to elucidate the factors that control the abiotic
transformation of herbicides in wetland sediments.
Rationale; The fate of synthetic agrochemicals in natural waters is an important environmental issue due
to the potential toxic effects that they or their degradation products may exhibit. Many herbicides enter
waterways through surface runoff and collect in the sediment phase of wetlands, which then controls the
distribution and degradation of these species. Because most commercial herbicides are simple organic
compounds, traditional techniques of reaction chemistry can be employed to study the transformation
processes. An extensive investigation is proposed to determine how geochemical conditions in wetland
sediments promote abiotic reactions of various herbicides. The results will give scientists the ability to
predict the fate of an herbicide in a wetland environment. Moreover, such information could be used for the
development of "green" herbicides that degrade quickly into non-toxic products.
Approach; Certain nitroaromatic compounds (e.g., Trifluralin, Dinoseb) are used commercially as
herbicides, and may be expected to accumulate in wetlands located near agricultural sites. Dissolved Fe(II)
and iron oxide minerals are often abundant in freshwater wetland sediments. Under these conditions,
nitroaromatic compounds can be reduced to the corresponding aniline species (Klausen, J.; Trober, S. P.;
Haderlein, S.B.; Schwarzenbach, R.P. Environ. Sci. Technol. 1995; 29:2396-2404). Natural organic matter
(NOM) found in wetland sediments may influence these reactions by complexing Fe(II) and/or adsorbing
on mineral surfaces. Laboratory studies will explore the fate of nitroaromatic herbicides in iron-based
reducing systems, with NOM content varied as an independent parameter. Analytical techniques available
for studying the reactions include high-performance liquid chromatography (HPLC) and gas chroma-
tography/mass spectrometry (GC/MS). Additionally, field studies will be performed in order to characterize
the reducing conditions found in natural wetland sediments. In conjunction with this work, herbicide
reductions can be performed in microcosm experiments using sediments and/or sediment porewaters
extracted from selected wetlands.
Status; In laboratory experiments, the fungicide pentachloronitrobenzene is reduced by Fe(II)/goethite to
produce pentachloroaniline. The reaction rate is significantly faster than that for nitrobenzene, due to the
difference in reduction potential between the two compounds. Therefore, it is possible that natural
degradation of pentachloronitrobenzene may be a rapid process. Ongoing experiments are investigating how
the reaction is influenced by NOM, molecular oxygen, and additional mineral phases.
Papers & Publications; None at this time.
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U915230
HIGHLAND AND LOWLAND LAND-USE AMONG THE Q'EQCHF-MAYA
Paul D. Kockelman
University of Chicago
Objectives/Hypotheses: Current project location is the highlands of Guatemala, in a Q'eqchi'-speaking
community of some 80 families. Current research focuses on changes in women's roles, social relations,
and productive practices as they, the objects they produce and own, and the subjects they bear, bury, and rear,
move from circumscription within the domestic mode of production to more distally circulating systems of
value, more tenuous social networks, and more national—indeed, international—regimes of discourse. In
particular, I am analyzing the changes in women's intentional lives as they begin to act as hosts, cooks, and
guides for an increasingly successful eco-tourist project, as they begin to move into small craft production
for market sale (including textiles, basket-work, and produce), and as their husbands, fathers, and sons begin
to spend more and more time away from the village as seasonal laborers on distant fincas (now, on average,
almost 5 months per year).
Rationale; This research provides a comparison with previous work done among speakers of Q'eqchi'
living in the lowlands of Guatemala. In particular, it allows one to assess the changes occurring in economic,
social, and ecological relations as Q'eqchi' speakers migrate from the highlands of Guatemala to the
lowlands, and as they interact with environmentally-minded governmental and non-governmental organi-
zations.
Approach; Comparative analysis of highland and lowland speakers of Q'eqchi'-May a in regards to their
social networks, ecological knowledge, and cultural values as seen in the context of recent events and
historical changes.
Status; Most data collected and currently being analyzed. Data collection will be finished in fall 2000.
Papers & Publications; Kockelman, P.D. 2000. The collection of Copal among the Q'eqchi'-Maya.
Economic Anthropology.
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STAR Graduate Fellowship Conference
U915233
NATURE AND THE CULTURAL POLITICS OF DIFFERENCE
IN NORTHEN NEW MEXICO
Jon Kosek
University of California, Berkeley
Objectives/Hypotheses; This dissertation demonstrates the ways in which cultural politics of nature have
been central to the formation and reproduction of difference in northern New Mexico. More specifically,
it demonstrates how the practices and conflicts surrounding the forestand its management are simultaneously
and inseparably bound to the formation and reproduction of race, class, and nation.
Rational: Over the last decade, the nature of forestry in the United States has changed drastically. With
declining faith in government institutions and increasing global pressures to deregulate everything from
welfare to clean water to make room for the "free market," the role of the state is shifting dramatically.
These changes have led to a new and still ambiguous role for state resource agencies. After decades of
policies, which have often done more harm than good to communities and forests, the Forest Service is
experiencing a time of intense internal crisis and a rise in often violent conflict with the groups it purportedly
serves. At the same time, forests are undergoing intense pressure as development areas for second homes
and home offices of telecommuters; they are shifting from primarily spaces of extraction to spaces of leisure.
These shifts—away from a strong state on a "global" scale, the increasing resistance to forest management
by community groups, and the changing uses of forests—have inadvertently opened up new spaces from
which community groups can challenge present management and ownership of forest resources and develop
new visions of forestry. These new spaces are fragile and in large part on what extent the resources are
controlled or influenced by local groups. If resources are in the hands of others, it is unlikely communities
will have signifigant influence on how resources are used and who benefits from there use. My poster will
explore how these larger national or global trends mix with local histories and social relations in ways that
reformulate the directions of and opportunities for community forestry. At stake are the livelihoods of
people in the community of Truchas, New Mexico, where I will work, as well as other resource-dependent
communities, the authority of federal officers and institutions, the identities of opposing groups and
individuals, and the potential ecological trajectories of the forests. By exploring the process by which
identities are naturalized and by which nature is intertwined with the politics of identity, I hope to bring new
understanding to both forest controversies and environmental justice.
Approach: I will interview community leaders, Forest Service officials, and environmental group staff; I
will attended public meetings and conduct participant observation in forest related activities. I will collect
information concerning economic activities and relationships, and about individual knowledge of both forest
histories and social movements. I will also collect archival data on the history of forest tenure, race relations,
and forest conflicts.
Status; I have just completed my field work in New Mexico and am starting my dissertation writing phase.
Papers & Publications; None at this time.
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U915602
PRIVATE PROVISION OF PUBLIC GOODS: ENVIRONMENTAL IMPROVEMENT
THROUGH 'GREEN' ELECTRICITY CONSUMPTION
Matthew J. Kotchen
University of Michigan
Objectives/Hypotheses; Economists have recently identified information-based approaches as a general
instrument of environmental policy. These strategies are based on the premise that increasing the availability
of information will mitigate informational market failure, reduce transaction costs, and induce market forces
to adjust toward more efficient pollution control. Such a strategy may serve as a complement or a substitute
to command-and-control and market based instruments of environmental policy. Markets for green
electricity (electricity generated from renewable energy sources) are cited as a prominent example of the
information-based approach. Participants in green electricity programs voluntarily pay a price premium to
displace conventionally generated electricity with green electricity. Within the context of environmental
improvement through green electricity consumption, this research seeks to advance and test theoretical
predictions from economics on the private provision of public goods.
Rationale: Evaluate the potential for voluntary approaches to environmental policy from the perspective
of economic theory on the private provision of public goods.
Approach; Voluntary participation in a green electricity program reveals a willingness to incur private costs
for public benefit. Green electricity provides pollution reduction (a pure public good) by displacing
electricity generated from fossil fuels. The theoretical component of this research extends economic theory
on the private provision of public goods. The framework seeks to explain who contributes, and who free
rides, on private initiatives to provide an environmental public good. A substantive component of the
research is to evaluate different models and motivations for individual decision-making. The empirical
component of this research involves testing hypotheses in natural experiments with the introduction of green
electricity programs. Data wilt be collected from a combination of electric utility records and household
mail surveys of program participants and nonparticipants. These data will be used to evaluate different
theoretical specifications.
Status: The theoretical basis of this research is still in the developmental stage, and plans are underway to
coordinate data collection across different green electricity programs.
Papers & Publications; Kotchen, M.J., Moore, M.R., and Clark, C.F. Individual-industry voluntary
contracts: the case of 'green' electricity. In: Environmental Contracts and Regulatory Innovation:
Comparative Approaches in Europe and the United States. E. Orts and K. Deketelaere (eds.). Netherlands:
Kluwer Law International, (in press)
Kotchen, M.J. and Moore, M.R. 1999. A model of the green consumer: from voluntary restraint to a
voluntary price increase. Paper presented at the Heartland Environmental and Resource Economics
Workshop, Iowa State University, September 19-21.
Clark, C.F., Kotchen, M.J., and Moore, M.R. Internal and external influences on behavior: an analysis of
participation in a green electricity program, (currently in review)
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U915338
IMPACTS OF THE ARGENTINE ANT (LINEPITHEMA HUMILE) ON POLLINATION
Lori J. Lach
Cornell University
Objectives/Hypotheses: To experimentally investigate the impacts of the Argentine ant (Linepithema
humile) on pollination of: 1) Protea nitida, a fynbos plant of the southwestern Cape Province of South
Africa; and 2) Metrosiderospolymorpha, a dominant native tree in Hawaii Volcanoes National Park.
Rationale; Pollinators are widely believed to be imperiled and competition with invasive species is
hypothesized to be partly responsible for their demise. The Argentine ant has invaded parts of the United
States, Bermuda, Chile, Portugal, and South Africa, and is considered a threat to native invertebrates
wherever it establishes. In at least one case, it has been shown to have both superior exploitation and
interference competition abilities relative to competitors. Its competitive abilities against pollinators are
largely unexplored. The ant is adept at locating and efficient at harvesting nectar resources of both P. nitida
and M. polymorpha. Native ants are rarely seen on P. nitida and there are no native ants in Hawaii to forage
on M. polymorpha. It is, therefore, unlikely that in either case native pollinators would have evolved the
means to overcome interference by the Argentine ant. In fact, a preliminary study in South Africa suggests
that Argentine ants are affecting the abundance often potential pollinators of P. nitida. Experimentally
demonstrating impacts to conservation in these two very different systems would provide evidence for a
hypothesized but untested impact of a widespread invader on a crucial ecosystem service, and would supply
conservationists, land-managers, and policy makers with further reasons to actively prevent the spread of
invasive species.
Approach; P. nitida: I will select pairs of buds from the same tree at the same stage of development in both
Argentine ant-infested and native ant inhabited sites. I will allow ants to forage as usual on half of the buds
and exclude them from the other half. At peak bloom, I will harvest a subset of the pairs and compare the
differences in abundance and diversity of invertebrates in the flowerheads, particularly potential pollinators,
between ant-allowed and ant-excluded inflorescences for both sites with Argentine ants and sites with native
ants. The remaining pairs will be harvested after seed set. I will compare the differences in percent of fertile
seeds between ant-allowed and ant-excluded infructescences for sites with Argentine ants and native ants.
To determine the extent of the threat that Argentine ants pose to proteas in the southwestern Cape, many of
which are endemic and over a third of which are endangered, I will survey other proteas within the Argentine
ant's range for its presence, and analyze foraging patterns with respect to nectar abundance and composition,
and morphology and phenology of the flowers.
M. polymorpha: I will employ the same techniques as above for the exclusion, however, the experiment will
be done only in Argentine ant-infested areas. I will compare frequency and species of visitors to ant-allowed
and ant-excluded flowerheads and will measure the amount of nectar in ant-allowed and ant-excluded
flowers. I will harvest all infructescences after seed set and compare percent of viable seeds between
ant-allowed and ant-excluded infructescences.
Status; The P. nitida experiments are underway. Peak bloom occurs in May-June and seed set will take 8-9
months. I have piloted the M. polymorpha experiment and will conduct it during the June-July 2000 bloom.
Papers & Publications; None at this time.
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U915406
NEGOTIATING CONSERVATION: PEASANTS AND FOREST CONVERSION
IN THE BUFFER ZONE OF THE INDIO-MAIZ RESERVE, NICARAGUA
Anne M. Larson
University of California, Berkeley
Objectives/Hypotheses; To understand how and why some peasant colonists organize to conserve forest
resources in colonization areas where the vast majority of peasants convert forest to agriculture and pasture.
Rationale: Rainforest conversion by peasant colonists is one of the main causes of tropical deforestation,
and successful attempts to stop or slow this process are rare. Park strategies that exclude local populations
from the forest are top-down solutions that often generate new conflicts and thus, may increase overall
destruction; in addition, Third World governments rarely have the resources or political will to enforce park
boundaries. Bottom-up perspectives argue that local organization and resource control provide the most
equitable and effective solution: local peoples will protect natural resources in the interest of their own
livelihoods. In Nicaragua, NGOs and government agencies have promoted a combination of park and local
development strategies in the face of massive colonization of Rio San Juan, one of its last frontier areas, over
the past 10 years. This study will examine two of the very few identifiable "successes."
Approach: This research seeks a balance between understanding structural constraints and local agency,
and between economic and a broader social analysis of meanings, conflict and negotiation. It uses a political
ecology approach, combining historical with multi-scale analysis grounded in the in-depth study of two
grassroots organizations. The primary research tools are interviews with multiple actors and the review of
historical and policy documents and the media. The core of the research are case studies with men and
women from 30 households participating in one of two peasant organizations promoting rational forest use,
and a survey of 130 members and non-members. These studies analyze production practices, who joins the
organizations and why, and their goals and understanding of "conservation." Interviews with prominent
projects and NGOs, and the review of government documents and the media, allow for an examination of
discourses and practices regarding concepts of development and conservation, and the role of the peasantry
in forest conversion. The current institutional framework of the two relevant municipalities has been
analyzed through interviews with government, timber industry, NGO and peasant leaders. The history of
Rio San Juan provides the basis for understanding its symbolic, political and economic importance to
different actors today.
Status; All historical, national and regional research is completed, as well as research on one local
organization. The second organizational study is underway and will be completed by May 2000.
Papers & Publications; Larson, A. 2000. Peasant agroforesters: fiction or reality? Paper presented at the
meeting of the Latin American Studies Association, Hyatt Regency, Miami, March 16-18.
Larson, A. and Barahona, T. 1999. San Carlos: una oportunidad despreciada? Proyecto: el papel de los
gobiernos municipales en la gestion de los recursos naturales. Managua: Nitlapan/CIFOR.
Larson, A. and Barahona, T. 1999. El Castillo: la colonizacion y las empresas madereras en una zona de
amortiguamiento, proyecto: el papel de los gobiernos municipales en la gestion de los recursos naturales.
Managua: Nitlapan/CIFOR.
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Larson, A. 1995. Land tenure and deforestation in Nicaragua: the reopening of the agricultural frontier in
Rio San Juan. Paper presented at the meeting of the Latin American Studies Association, The Sheraton
Washington, September 28-30.
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U915337
ECOLOGY AND POPULATION REGULATION OF NEOTROPICAL
MIGRATORY BIRDS ON HISPANIOLA
Steven C. Latta
University of Missouri, Columbia
Ob j ectives/Hvpotheses: To provide a better understanding of the ecology of Neotropical migratory birds
wintering in three habitats across an altitudinal gradient in the Dominican Republic and to assess the ideal
despotic model of winter population regulation of these birds.
Rationale; Recent evidence suggests declines in numerous migratory bird species. Whether these declines
are the result of breeding ground, wintering ground, or migratory events, or a combination of factors in the
annual cycle has been widely debated. Studies of wintering migrants have generally reported species
distributions and determined habitat suitability based on abundance indices, but few demographic data have
been available from wintering sites to assess species trends or factors affecting overwinter survival.
One model of winter population regulation in migrants predicts that habitat of optimal suitability will be
occupied before habitat of lower suitability, and that settlement of subsequent individuals will be constrained
by territorial behavior. Fitness variation results because fitness (in terms of survival) is expected to decline
with increased density of birds and from optimal to suboptimal habitats. Fitness may also vary between:
1) sex or age class due to segregation between habitats; 2) territorial birds and "floating" individuals who
adopt a wandering strategy due to the presence of territorial conspecifics in all suitable habitats; and 3)
territorial individuals and migrants who join mixed species flocks.
Approach; Specifically, I seek to address the need for habitat specific demographies in a study of migrants
wintering in three critically threatened and migrant-rich habitats-coastal desert thorn scrub, dry broadleaf
forest, and pine forest-along an altitudinal gradient on Hispaniola. In each habitat, specific fitness indices
such as home range size, site fidelity, overwinter turnover, and annual return rates will be quantified and
compared by species, sex, and age class. I will also use behavioral observations to determine what foraging
and social strategies are used by migrants in these habitats, whether these vary by sex and age class, and how
social behavior relates to measures of fitness. These measures will allow me to compare fitness values
between habitats on Hispaniola and other islands.
Status; Data collection has been completed and most preliminary analyses are done. I expect to finish my
dissertation in August 2000.
Papers & Publications; Latta, S.C. and Lorenzo, R. (eds.). Results of the national planning workshop for
avian conservation in the Dominican Republic. Direccion Nacional de Parques, Santo Domingo, Dominican
Republic. 137pp. (in press)
Latta, S.C., Sondreal, M.L., and Brown, C.R. A hierarchical analysis of nesting and foraging habitat for the
conservation of the Hispaniolan White-winged Crossbill (Loxia leucoptera megaplagd). Biological Con-
servation (in press)
Wunderle, J.M., Jr. and Latta, S.C. Winter site fidelity of Nearctic migrant birds in isolated shade coffee
plantations of different sizes in the Dominican Republic. Auk (in press)
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Latta, B.C. 2000. Making the leap from researcher to planner: lessons from avian conservation planning
in the Dominican Republic. Conservation Biol 14:132-139.
Latta, S.C. and Brown, C. 1999. Autumn stopover ecology of the Blackpoll Warbler (Dendroica striatd)
in thorn scrub forest of the Dominican Republic. Can J Zool 77:1147-1156.
Latta, S.C. and Sondreal, M.L. 1999. Observations on the abundance, site persistence, home range, foraging,
and nesting of the Pine Warbler on Hispaniola, and first record of ground nesting for this species. Ornitologia
Neotropical 10:43-54.
Klein, N.K., Sheldon, F.H., Wallace, K., Cuevas, E., and Latta, S.C. 1998. Use of a small water reservoir
by locally rare birds in the Dominican Republic. El Pitirre 11(2):36.
Latta, S.C. (ed.). 1998. Recent ornithological research in the Dominican Republic/Investigaciones
ornitologicas recientes en la Republica Dominicana. Ediciones Tinglar, Santo Domingo, Dominican
Republic. 130pp.
Latta, S.C. and Wunderle, J.M. 1998. The assemblage of birds foraging in native West Indian pine (Pinus
occidentalis) forests of the Dominican Republic during the nonbreeding season. Biotropica 30:645-656.
Latta, S.C. and Baltz, M. 1997. Population limitation in Neotropical migratory birds: Comments on
Rappole and McDonald (1994). Auk 114:754-762.
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U915587
FROM YELLOWSTONE TO YUKON: COMBINING SCIENCE AND ADVOCACY
TO SHAPE PUBLIC OPINION AND POLICY
Suzanne M. Levesque
University of California, Irvine
Objectives/Hypotheses; To apply qualitative research tools to the study of the use of scientific knowledge
by environmental advocates. The goal is to provide essential information about the relationship between
science and advocacy and about the conditions under which environmental advocates may achieve support
for their proposals. This knowledge may assist policy-makers to understand and mediate among competing
environmental interests.
Rationale; Scientists and activists are now forming extensive networks to cooperate in the achievement of
environmental goals. These networks are likely to become increasingly important players in policy making
arenas from the local to the international level, shaping social, economic, political and environmental
agendas within and between nations.
While scientific information serves as a key source of legitimacy and credibility within the environmental
advocacy realm, little research has been conducted on the relationship between scientific knowledge and
expertise and informed citizen action on behalf of the environment. This study examines the interaction
between science and citizen advocacy within the context of an international environmental network
composed of scientists and activists-the Yellowstone to Yukon Conservation Initiative, or "Y2Y." The
findings of this study may help policy-makers understand and mediate among contending interests when
making policy decisions.
Approach; This research uses qualitative research tools, including network, discourse and context analysis,
to explore the interactions between science and advocacy in network processes in the Yellowstone to Yukon
Conservation Initiative, a transboundary environmental network whose goal is the preservation of
biodiversity. Research findings are based on content analysis of data gathered as a participant observer at
network meetings, on a series of 31 semi-structured interviews conducted with participants most centrally
involved in the network, on all available archival data produced by the network since its inception, and on
electronic mail communications with and among network members.
Status; I am in the final stages of dissertation writing. I expect to complete and defend the dissertation in
May 2000 and receive my degree in June.
Papers & Publications; Blatter, J., Levesque, S., and Ingram, H. 2000. Shifting perspectives on trans-
boundary water. In: Joachim Blatter and Helen Ingram (eds.), Governance, Territoriality and Beyond:
Emerging Perspectives on Transboundary Water and Natural Resources.
Levesque, S. 2000. The Yellowstone to Yukon conservation initiative: reconstructing boundaries,
biodiversity and beliefs. In: Joachim Blatter and Helen Ingram (eds.), Governance, Territoriality and
Beyond: Emerging Perspectives on Transboundary Water and Natural Resources.
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U915339
COMPLEX INTERACTIONS IN ESTUARINE SALT MARSH COMMUNITIES
David B. Lewis
University of Wisconsin, Madison
Objectives/Hypotheses; To determine whether physical modification of salt marsh habitat by invading
species alters interactions among native species.
Rationale: Feral horses were introduced to barrier islands along the east coast of the United States,
presumably during colonial periods. Though an aesthetic appeal for these animals inspires maintenance of
their populations, many direct impacts of their grazing on marsh plants have been documented. Whether
these grazing activities subsequently influence more complex processes, such as predator-prey interactions
among native fauna, remains unknown. This issue, which lends itself to tests of basic ecological hypotheses
regarding ecosystem engineers, forms the orientation of my research.
Approach; Field surveys and modeling exercises were used to generate three predictions about the
interactions between blue crabs (predators) and periwinkle snails (prey). First, predation intensity should
increase from high elevation portions of the marsh to the low marsh near tidal creeks and bays. Second,
predation will be more intense in areas with short marsh grass and less intense where taller grass provides
refuge for snails. Third, these predation gradients ordered by elevation and vegetation height may interact.
Where marsh grass is short, the disparity between high marsh and low marsh in predation intensity should
be negligible. Where grass is tall, however, predation intensity in the low marsh will be greater than in the
high marsh. To test these predictions, we cut several experimental channels from low to high marsh through
marsh grass. Each channel was paired with an uncut reference transect, and we monitored sizes and
abundances of crabs and predation rates on tagged snails.
Status: In review.
Papers & Publications: Lewis, D.B. and Magnuson, J.J. 1999. Intraspecific gastropod shell strength
variation among north temperate lakes. Canadian Journal of Fisheries and Aquatic Sciences 56:1687-1695.
Lewis, D.B. and Magnuson, J.J. 2000. Landscape spatial patterns in freshwater snail assemblages across
Northern Highland catchments. Freshwater Biology 43:409-420.
Lewis, D.B. 2000. Freshwater snail responses to predatory crayfish: trade-offs between growth and survival.
Ecology 81 (in press)
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U915179
USING A PHYSIOLOGICALLY BASED PHARMACOKINETIC MODEL
FOR METHYL TERT-BUTYL ETHER IN HUMANS
TO INVESTIGATE VARIABILITY IN METABOLIC ENZYMES
Amy Collins Licata
North Carolina State University
Objectives/Hypotheses; The objective of this study was to verify the ability of a physiologically based
pharmacokinetic (PBPK) model to predict methyl tert-butyl ether (MTBE) blood levels in humans following
inhalation exposure and to investigate the high variability found in the metabolic parameter VMAX.
Rationale; By enacting the 1990 Clean Air Amendments, Congress specified that changes be made to
reformulate gasoline as an effort to reduce carbon monoxide (CO) and ozone, two key National Ambient Air
Quality Standard (NAAQS) pollutants emitted primarily from motor vehicles. To achieve reformulated
gasoline and oxygenated gasoline, chemicals known as oxygenates can be added to fuel to reduce these air
pollutants from automobile emissions (Health Effects Institute, 1996). The gasoline additive MTBE is the
most frequently used oxygenate. Even though the purpose of using these oxygenates in gasoline is to achieve
attainment with the NAAQS, concern has been raised regarding the toxicity of MTBE exposures. When
MTBE is added to gasoline, exposure to this chemical can occur through fuel evaporation or incomplete
combustion. Therefore, the obvious route of exposure is inhalation. However, due to leaking of underground
fuel storage tanks, MTBE has also been found in drinking water supplies. Thus, oral exposure to MTBE is
another concern. Yet, there is limited route-specific information for interpreting the potential risks of this
oxygenate in water (EPA, 1998). Currently, the EPA Drinking Water Advisory states the need for an
appropriate MTBE PBPK model to be used in the extrapolating of an inhalation dose-response to an
equivalent oral dose-response given the limited oral data available (EPA, 1997).
Approach: My research involves the development of a MTBE PBPK model to evaluate more accurately
the exposure-dose relationship in humans. In the development of a MTBE PBPK model for humans, several
new sources of human data, including MTBE blood and urine concentrations (Cain et al., 1996; and Amberg
et al., 1999) and MTBE-specific parameter values, such as partition coefficients and metabolic rate constants
(Nihlen et al., 1995; and Poet and Borghoff, 1998), are utilized in my model. This PBPK model also
incorporates more relevant data that represents human exposure scenarios including low and high dose
inhalation exposures (4 ppm and 40 ppm MTBE) (Amberg et al., 1999). Additionally, my model incor-
porates data from existing mechanistic studies, which demonstrate that humans metabolize MTBE to its
major metabolite tert-butyl alcohol (TBA) by two different P450 enzymes, CYP2A6 and CYP2E1, and that
there is high variability found in the metabolic parameter VMAX in the CYP2A6 pathway. These data may
be used to predict the effect of variability in metabolism of MTBE in human populations and identify
sensitive subpopulations. While including human experimentally determined parameters, my PBPK model
for humans incorporates a statistical sensitivity analysis to evaluate relative importance of model parameters
to model output, blood concentrations of MTBE. This sensitivity analysis is extremely useful in determining
the affect of highly variable parameters, such as certain metabolic parameters, on model responses.
Status; Drs. Susan J. Borghoff, Wolfgang Dekant, and Charles Smith are contributing authors on this work.
This research will be developed into a manuscript and submitted to the journal ToxicologicalSciences. Ms.
Licata will be graduating this year with her Ph.D. from North Carolina State University.
Papers & Publications; Amberg, A., Rosner, E., and Dekant, W. 1999. Biotransformation and kinetics
of excretion of methyl-tert-butyl ether in rats and humans. Toxicol Sci 51:1-8.
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U915147
MEASURING THE EXTENT AND IMPACT OF BIOTIC INVASIONS: CASE STUDY
OF SIGNAL CRAYFISH IN SIERRA NEVADA (CA) STREAMS
Theo S. Light
University of California, Davis
Objectives/Hypotheses; My research examines the distribution and impacts of the introduced signal
crayfish (Pacifastacus leniusculus) in streams of the Truckee River drainage in the eastern Sierra Nevada,
California. My major questions are: 1) Is the extent of this invasion limited by the naturally variable flow
regime of California streams, or conversely, facilitated by the many small reservoirs and regulated stream
reaches in this system? and 2) What are the community impacts of signal crayfish on native benthic
organisms, particularly Paiute sculpin (Cottus beldingi), and on food web processes in Sagehen Creek?
Rationale; Invasion theory suggests that disturbance enhances the establishment of exotic organisms.
However, in California, much evidence suggests that the naturally high disturbance levels of unregulated
streams help to limit their invasibility. Human reductions of this natural variability, via impoundments,
diversions, and flow regulation, appear to facilitate aquatic invasions in California. Community impacts of
invasions, including subtle shifts in behavior or food web functioning, have been widely hypothesized but
remain poorly understood.
Approach: 1) Extent of invasion: In summers 1994 and 1998,1 surveyed most streams of the Truckee
River basin for signal crayfish. For each stream section sampled, I measured flow and average stream width
and depth in the field, and determined gradient, elevation, stream order, and distance to the nearest
impoundment from topographic maps. I am analyzing these variables using multivariate techniques in order
to identify factors associated with crayfish presence and abundance. Three streams (two with natural
hydrographs, one regulated) have been sampled quantitatively for crayfish and sculpins each year of my
study (1994-98); all three of these streams have hydrologic (flow) data available from the USGS. Using
time-series analysis, I will examine the association of winter high flow events (timing and severity) with the
distribution and abundance of crayfish in the following season. 2) Community effects of crayfish: I am
examining crayfish effects on native Paiute sculpins and benthic food webs using a combination of field cage
experiments, field removals, and behavioral experiments in a semi-natural observation stream. In addition,
I will use data from field surveys of crayfish and sculpins to examine associations between the two species
and winter flood effects on sculpins. Cage experiments manipulating densities of crayfish and sculpins were
completed in 1995 and 1996. I measured growth rates of both species in sympatry and allopatry, and
assessed their impacts on algal and invertebrate biomass and diversity on artificial substrates. Behavioral
experiments in 1996 and 1998 assessed the impacts of crayfish presence on sculpin shelter use, feeding rate,
velocity microhabitat selection, and overall activity level. Field removal experiments involved crayfish
removal from randomly-selected pools in an area of high crayfish density in Sagehen Creek. I examined
effects of crayfish removal on invertebrate abundance and diversity, algal biomass, and sculpin abundance
and position in pools.
Status; I completed the major field component of my research in the summer 1998 field season. Data
analysis is essentially complete, and I am compiling and writing up my results.
Papers & Publications; Marchetti, M.P., Light, T., Feliciano, J., Armstrong, T., Hogan, Z., Viers, J., and
Moyle, P.B. 2000. Homogenization of California's fish fauna through abiotic change. Ch. 13 in J.L.
Lockwood and M.L. McKinney, eds. Biological Homogenization. Kluwer Academic/Plenum Publishers,
New York.
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U915660
THE ROLE OF CHEMICAL MIMICRY IN THE ECOLOGY AND EVOLUTION
OF SYMBIOSES BETWEEN LYCAENID BUTTERFLY CATERPILLARS
(LEPIDOPTERA: LYCAENIDAE) AND ANTS (HYMENOPTERA: FORMICIDAE)
David J. Lohman
Harvard University
Objectives/Hypotheses; The objectivesof my current work include identifying the pheromones responsible
for ant-specificity in varied ant-lycaenid caterpillar symbioses, determining the degree to which these
pheromones have acted as an evolutionary constraint in the focal genus, Ogyris, and to better understand the
evolution of ecological specialization in the focal genus, Jalmenus.
Rationale: Resource specialization is a hallmark of many ecological interactions, and specialized
interactions between plants and their herbivores and pollinators have been fruitful paradigms for ecological
and evolutionary studies, but other different systems also promise to offer great utility in such investigations.
Worldwide, the immature stages of about half of all lycaenid butterfly species associate with ants in
relationships that vary from mutualisms to parasitisms, and these interactions are generally species-specific.
Some lycaenids associate with only one or a few ant species, but many are promiscuous in their choice of
ant partners. The data collected thus far indicate that the degree of similarity between the articular
hydrocarbon recognition pheromones of the caterpillars and those of their attending ant species' brood
determines whether a given ant species will attack or not attack a particular lycaenid species. This may
determine ant specificity, and will be studied using the focal genus Jalmenus. Phylogenetic reconstruction
of the genus Ogyris and other ant-tended genera reveal constraint along ant lines, whereby clades within the
butterfly genus specialize on different clades of ants. If cuticular chemistry is an evolutionary constraint,
then predictable patterns should be found in the hydrocarbons of these caterpillars and their ant associates.
Ant association is fundamental to the survival of many of these butterflies and their 'host ant' breadth likely
dictates the population structure and evolution of ant-tended lycaenids.
Approach; Gas chromatography-mass spectroscopy is being used to determine the chemical structures of
each species' suite of hydrocarbon pheromones, and the hydrocarbon profiles will be compared statistically
using principle components analysis. Bioassays in which ants are made to tend novel caterpillars-by
applying the pheromones of caterpillars normally found with that ant-may confirm that these chemicals are
causing the 'adoption' behavior of caterpillars by ants. Assessments of recognition pheromones as an
evolutionary constraint and as the determinants of ant-specificity will be made by comparing relevant
chemical profiles from species in the butterfly genera Jalmenus and Ogyris with their respective associated
ants in a phylogenetic context. Molecular markers will be employed to assess inbreeding and population
structure in phylogenetically paired ant-generalist/ant-specialist lycaenid butterfly pairs.
Status; Over 200 chemical samples have been collected from lycaenid caterpillars and the workers/brood
of their tending ants in Australia, the United States, and South Africa. Several taxa from the genus Ogyris
are included in this sample. A selected set of these samples have been analyzed to substantiate the
hypothesized patterns, and future extractions from the focal, Australian genera Jalmenus and Ogyris are
planned for October 2000 - April 2001, as are field bioassays.
Papers & Publications; Lohman, D.J. and McConnaughay, K.D.M. 1998. Patterns of defensive chemical
production in wild parsnip seedlings (Apiaceae: Pastinaca saliva L) Chemoecology 8:195-200.
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Lohman, D.J. 1999. Chemical communication between the obligately myrmecophilous phytophage Jal-
menus evagoras (Lycaenidae) and its attendant ants. Oral presentation at the November 1999 Second
International Lepidopterists' Conference of Africa, Cape Town, South Africa.
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U915347
CHARACTERIZATION OF SOURCES OF INDOOR PARTICLES USING
CONTINUOUS MASS AND SIZE MONITORS
Christopher M. Long
Harvard University
Objectives/Hypotheses; The objective of my doctoral research is to use novel monitoring and modeling
techniques to characterize and quantify sources of indoor fine particulate matter.
Rationale; Because people spend approximately 80-90% of their time indoors, it is widely recognized that
a significant portion of total personal exposures to particulate matter occurs in indoor environments.
However, despite the public health implications of indoor particle exposures, there are relatively few data
characterizing the sources and behavior of indoor particles. Major questions and uncertainties still remain
concerning the relative contribution of ambient versus indoor particles to indoor particulate levels and the
factors (e.g., indoor source strengths, air exchange rates, decay rates, infiltration rates) influencing indoor
particle levels.
Approach; A comprehensive indoor particle characterization study was conducted in nine Boston-area
homes in 1998. Extensive field sampling was conducted over week-long periods in nine non-smoking
Boston-area homes, including five homes which were sampled during two seasons. Continuous PM25
concentrations were measured inside and outside each home using the Tapered Element Oscillating
MicroBalance (TEOM) and the Continuous Ambient Mass Monitor (CAMM). Real-time size distribution
data were simultaneously collected for indoor and outdoor air using the Scanning Mobility Particle Sizer
(SMPS) and the Aerosol Particle Sizer (APS). In addition, time-integrated particle samples were collected,
including PM2 3 samples for chemical analysis (e.g., elemental/organic carbon and trace elements), and
continuous air exchange rates and detailed time-activity information were recorded.
Status; My first paper was recently accepted by the Journal of the Air & Waste Management Association.
I am currently working on a second manuscript that focuses on the issue of ambient particle infiltration. I
expect to complete my doctoral thesis sometime in the 2000-2001 academic year.
Papers & Publications: Long, C.M., Suh, H.H., and Koutrakis, P. 2000. Characterization of indoor par-
ticle sources using continuous mass and size monitors. J. Air & Waste Manage Assoc (accepted)
Long, C.M., Suh, H.H., and Koutrakis, P. 2000. Using time- and size-resolved particulate data to investigate
infiltration and deposition behavior. Platform paper presented at the PM2000 Specialty Conference
Charleston, SC, January 24-28, 2000.
Long, C.M., Suh, H.H., and Koutrakis, P. 2000. Characterization of indoor particle sources using contin-
uous mass and size monitors. PosterpresentedatthePM2000SpecialtyConference,Charleston SC January
24-28,2000. J
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U915192
DUST RESUSPENSION BY WIND AND THE IMPLICATIONS
FOR CONTAMINANT TRANSPORT
Gwen A. Loosmore
University of California, Berkeley
Objectives/Hypotheses; The goal is to conduct a wind-tunnel study of the resuspension of dust by wind,
under conditions where no flux would be predicted by conventional models. The hypothesis of the current
investigation is that there are small but steady long-term dust fluxes where none are predicted, below the
threshold velocity and after the initial transients.
Rationale; Direct wind resuspension provides a source of dust to the atmosphere, where the particles may
pose a risk to human health, mediate chemical reactions, act on global climate, and transport contaminants
such as radionuclides and pesticides. Predicting dust flux under various atmospheric and surface conditions
has proven difficult, with field data showing great variability, and models rely heavily on empirical
parameterizations. One common parameter is the threshold velocity. Models typically assume there will
be no flux until the threshold velocity has been exceeded. These critical velocities are often identified by
visual observation of a soil surface, an approach more applicable to soil erosion than small dust fluxes.
Regulatory dust flux models further assume that direct wind resuspension occurs only for high wind events
and then only transiently (on the order of minutes) when the surface is first exposed to the high wind. In the
long term, the surface is assumed to stabilize, with no further dust released until the surface is disturbed or
exposed to a higher wind. The hypothesis of the current investigation is that there are small but steady
long-term dust fluxes where none are predicted, below the threshold velocity and after the initial transients.
Approach; To ensure that any dust flux measured is a result only of the below-threshold wind action, the
present investigation utilizes an idealized PM10 source in a wind tunnel, in a laboratory with controlled
temperature and humidity. The velocities and turbulent intensities in the wind tunnel are characterized using
thermal anemometry. The upstream and downstream dust concentrations are measured isokinetically using
TSI DustTrak Aerosol Monitors. Experiments consist of exposing the idealized soil to a mean velocity
below the threshold velocity recommended by the literature. (After an initial flurry, lasting a few seconds,
no dust movement has been observed visually under these conditions.) Experiments last approximately 30
minutes, well beyond the initial transient.
Status; Recent wind tunnel experiments confirm the hypothesis for an idealized soil and demonstrate that
surfaces yield continuous steady dust fluxes under steady wind conditions well after the initial high transient
flux, even when no erosion is visible and the velocity is below the predicted threshold velocity for
movement. The average steady-state long-term dust flux increases with average wind speed. This work calls
into question the assumptions in conventional models.
Papers & Publications; Loosmore, G.A. and Hunt, J.R. 1999. Dust resuspension as a contaminant exposure
pathway. UCRL-JC-132834, LLNL.
Loosmore, G.A. and Hunt, J.R. 1999. Dust Resuspension from an idealized soil: measurement of long-term
fluxes (oral presentation), AAAR, Tacoma, WA.
Loosmore, G.A. and Hunt, J.R. 1999. Dust resuspension as a contaminant source and transport pathway
(oral presentation and paper), Air and Waste Management Association Meeting, St. Louis, MO.
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U915640
PHOTOLYTIC IMPACT ON DISSOLVED ORGANIC MATTER: IMPLICATIONS
FOR COPPER-ORGANIC BINDING AND TOXICITY IN NATURAL WATERS
Marjorie B. Loworn
University of Wyoming
Objectives/Hvpotheses; To clarify the role of photochemical and microbial degradation of dissolved
organic matter (DOM) in altering the toxicity of copper (Cu) in natural waters.
Rationale; Cu-DOM binding in natural waters decreases the bioavailability of Cu to fish. However,
predicting the magnitude of this effect is complicated by the photochemical release of carbon from DOM
as greenhouse gases (CO and CO2). Additionally, organic macromolecules that dominate DOM are re-
fractory to microbial degradation, but sunlight partially degrades these molecules into low-molecular-weight
organics, which are microbially labile. Consequently, Cu toxicity depends not only on total DOM con-
centration, but also on the molecular composition of the DOM and continued removal of the Cu-binding
fraction by microbial degradation and photolysis. Work proposed here is the first to consider how the on-
going degradation of natural DOM alters its relative binding affinities for Cu and thus, Cu bioavailability
to fish.
Approach; I am currently,,conducting a series of experiments designed to investigate changes in the
physico-chemical, spectral, and Cu-organic binding characteristics of natural DOM before and after
controlled photodegradation under a full-spectrum solar simulator (Suntest CPS+).
Status: Experimental results support proof of the principal that photochemical breakdown of DOM alters
Cu toxicity and is essential to environmentally-relevant estimates of Cu-organic binding in natural waters.
The next series of studies will focus on direct measurements of photo-induced changes in the binding affinity
and complexation capacity of Cu binding sites on DOM.
Papers & Publications; None at this time.
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U915211
TEOSINTE BRANCHEDl AND THE DEVELOPMENT OF THE ADULT FORM
Lewis N. Lukens
University of Minnesota
Objectives/Hypotheses; This work has two objectives. First, models of inheritance often stress that in-
dividual alleles act additively to influence a given trait. These models typically ignore the effects of allelic
combinations (epistasis) and ignore the possibility that one allele may respond differently to changes in
environmental conditions than does another allele. This work examines the effect of epistasis and
allele-specificenvironmental responses on morphology using genetic differences between maize and its wild
ancestor, teosinte. Second, morphological differences among different species are often thought to be due
to small differences within multiple genes instead of large differences within a small number of genes. To
test this assumption, I have examined several morphologically diverse taxa and studied the evolution of a
gene known to have a major effect on morphology within these taxa. These experiments will add to our
understanding of how many genes contribute to the morphological diversity of plants, and how those genes
are regulated.
Rationale: To understand the importance of regulatory genes and genetic and environmental interactions
in plant development.
Approach; Previous work has identified five loci, which have contributed to the morphological evolution
of maize from teosinte. 1) To test for epistasis among alleles at two of these loci and to test if alleles at these
loci respond differently to changes in environmental conditions, two different alleles of both loci were
introgressed into an isogenic maize background. The four homozygous classes for the two loci were grown
in two environments, and three morphological traits and the level of mRNA accumulation for one locus were
measured. 2) To examine the pattern of nucleotide evolution within one locus, which is allelic to the gene
teosinte branched! (tbl), tbl sequences were cloned and sequenced from 30, morphologically diverse
grasses.
Status: All data collection is complete.
Papers & Publications; Doebley, J. and Lukens, L. 1998. Transcriptional regulators and the evolution of
plant form. Plant Cell 10:1075-1082.
Wang, R.L., Stec, A., Lukens, L., Hey, J., and Doebley, J. 1999. The limits of selection during maize
domestication. Nature 398:236-239.
Lukens, L. and Doebley, J. 1999. Epistatic and environmental interactions for quantitative trait loci in-
volved in maize evolution. Genetical Research 74:291-302.
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U915414
QUANTITATIVE MEASURES OF CHANGE IN PLEISTOCENE MAMMAL
DISTRIBUTIONS AND COMMUNITY COMPOSITION
Sara K. Lyons
University of Chicago
Objectives/Hvpotheses: Quantitative models have been applied to data for Pleistocene mammals to
examine the effects of climate change upon ecological communities. This study seeks to assess the sensitivity
of the results to model assumptions and to extend previous analyses to include changes in community
composition through both space and time.
Rationale; Whether species remain together or change association repeatedly through time is crucial to
questions about community structure and co-evolution as well as to understanding how species respond to
climate change (i.e., global warming). Examples of species that had sympatric ranges during the Pleistocene,
but are now allopatric have been reported in the literature and many researchers have concluded that
community composition is extremely plastic over time. Quantitative assessment of the range shifts of
Pleistocene mammals (measured by change in range size, and the distance and direction the centroid of a
range moved) indicates that the responses of species to climate change are inconsistent with a strict
interpretation of individualistic range shifts. Moreover, community composition in a particular locality is
more similar over time than would be expected given individualistic range shifts. This occurs because the
ranges of many species are changing small amounts relative to the overall size of their range. However,
these quantitative results are derived from simulation analyses that must be tested to determine the degree
to which they are sensitive to model assumptions. Moreover, these quantitative results only apply to
communities at a particular locality through time. Species that do show significant range shifts have been
shown to do so at different rates, and information about the degree to which species are moving together or
ending up in the same place has not been explored.
Approach; The basic model used to quantitatively evaluate the community structure of Pleistocene
mammals uses the following premise: if species are shifting their ranges independently, resulting in
non-analogue communities, then a similarity index calculated between a site at time tl and that same site
at time t2 (where tl is the oldest time period) should not be different from a distribution of similarity indices
calculated between a site at tl and randomly generated assemblages for time t2 (see EPA STAR abstracts,
1999 for a detailed description of the model). By altering each model assumption individually and
comparing the results to those of the initial model, I can assess the effects of the model assumptions.
Specifically, I address the effect of species that shift their distributions out of the United States (the spatial
extent of the FAUNMAP database), the effect of species that shift their range a small distance, and the effect
of similarity index. In addition, the model can be extended to include distance by calculating a similarity
index between each site at tl and all sites in the randomly created t2.
Status: The effect of the model assumptions has been tested. Conclusions about changes in mammalian
distributions and community composition are robust with respect to the assumptions of the model. The
model still needs to be extended to include both space and time.
Papers & Publications; None at this time.
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U915243
NEGOTIATED ACCESS: EMERGING INSTITUTIONAL FORMATIONS
IN THE FORESTRY SECTOR OF THE POST-SOVIET RUSSIAN FAR EAST
Marian J. Mabel
University of California, Berkeley
Objectives/Hypotheses; To examine the political-economic transformation of the forestry sector in the
post-Soviet Russian Far East and the institutional relationships that govern the globalization of the extractive
industry now characterized by fragmented and fluid systems of governance, jurisdiction, and management.
Rationale; Following the collapse of the Soviet system in 1991, the introduction of policies of economic
liberalization and administrative decentralization, and the opening of Russia's Far Eastern forest resources
to external markets, two interdependent dynamics came into play: competing efforts by federal, regional,
and local-level state institutions to appropriate control over forest resources under their territorial
jurisdiction; and globalization of the forestry sector, as foreign investment capital arrived to harvest and
export forest resources from the region. The study examines the interdependent dynamics of each of these
processes and asks what are the political-economic relationships of power that prevail in the forestry sector,
how has this evolved in the 1990s, and what are the implications for the entry and participation of foreign
capital. The research will inform discussions on political-economic issues affecting efforts toward
sustainable forest use in the Russian Far East, the potential for economic renewal and development of the
region's natural-resources sector, as well as implications for the international timber markets of the Pacific
Rim.
Approach: Analysis of institutional transformation and changing relationships of power between the state
and capital requires a methodology that approaches these analytical categories not as undifferentiated
structures or frames for other topics, but rather as sets of social processes that exist in and reflect their social
contexts. As such, I adopted a political-economy approach to examine processes and outcomes of relations
among the state and foreign capital in the forestry sector of Khabarovsk Krai in the Russian Far East. This
involved mapping the economic and political interface and flows among the players in the sector,
characterizing their links, examining the emerging institutional forms of these relationships, and exploring
the forces that strengthen or weaken them. My primary research tools included in-depth interviews
(individuals in the domestic public sector, private and private non-profit sectors, as well as international
development agencies, NGOs, and others involved in the forestry sector in the krai), legislative review,
statistical sectoral review, and on-site visits to harvest, management, and export operations. My research
was made possible through affiliation with the Economic Research Institute of the Far East Branch of the
Russian Academy of Sciences.
Status; I have completed my field research and am in the process of writing the dissertation. I expect to
be finished by December 2000.
Papers & Publications; Antonova, N. and Marian, M. 1998. The changes in management structure of the
Khabarovsky Krai forest sector during the period of economic reform. Bulletin of the Far East Branch of
the Russian Academy of Science. 1998, No.6. Khabarovsk, Russia.
Sheingauz, A., Marian, M., and Antonova, N. Globalization in the Russian far east forest industry. World
Forests, Society, and Environment, Volume III, Kluwer Academic Publishers, The Netherlands.
(forthcoming)
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U915340
POPULATION DYNAMICS OF METHANE-OXIDIZING BACTERIA
IN FLOODED SOILS: ENVIRONMENTAL CONTROLS ON COMPETITION
BETWEEN PHYSIOLOGICAL GROUPS
Jennifer L. Macalady
University of California, Davis
Objectives/Hypotheses; To identifyphysical.chemicaland biological factors controlling competition between
Type I and Type II methane-oxidizing bacteria and the extent of methane oxidation in flooded soils.
Rationale: The dramatic increase in atmospheric methane concentrations in the last 200 years has been
attributed to human activities such as agriculture and changes in land use. Atmospheric methane concentrations
continue to increase at the rate of 1-2% per year. Rice agriculture and other wetlands account for
approximately 30% of methane sources to the atmosphere. Previous studies have shown that methane-
oxidizing bacteria in flooded soils consume anywhere from 10 to 90% of gross methane production before it
reaches the atmosphere. The distributions and activities of two metabolically and physiologically distinct
groups of methane oxidizing bacteria in natural environments are poorly known. Existing global methane
budgets and models could be improved if factors controlling methane oxidation in flooded soils are better
understood.
Approach; Weekly methane flux measurements, soil porewater methane concentrations with depth, soil
temperature, and plant growth characteristics will be compared throughout the growing season at several field
sites in California including rice paddies farmed using contrasting agricultural practices and adjacent natural
wetlands. The distribution and activities of Types I and II methane oxidizing bacteria in intact soil cores and
in plant root/rhizosphere samples will be measured using phospholipid fatty acid (PLFA) analysis. The extent
of in situ methane oxidation (methane oxidation efficiency) will be calculated from measured "C values of
porewater methane and emitted methane using an isotope fractionation model. Trends in methane oxidation
efficiency will be compared with soil physical and chemical parameters, and with the population sizes of
methane-oxidizing bacterial groups. The data will be used to generate hypotheses about which factors control
the extent of methane oxidation in flooded soils. These hypotheses can be tested explicitly using laboratory
incubations.
Status; Methane flux measurements, soil porewater methane concentrations with depth, and rice growth
characteristics for the 1998 and 1999 rice growing seasons have been completed. Analytical methods for
quantifying Type I and Type II populations in soil and root samples developed last year have been employed
to give cell numbers of each methane-oxidizer type in 2-cm soil depth intervals from intact cores collected in
two rice fields (straw incorporation or straw burning treatments) and natural wetlands on several dates for each
year. Preliminary results indicate that rice straw treatments and rice growth stage (forms of carbon loading)
have no significant impact on competition between methane-oxidizer Types I and II, even though only Type
II can fix nitrogen. However, Type I methane-oxidizers make up a larger percentage of methane-oxidizers in
natural wetlands adjacent to the rice fields. Rice and wetland plant root samples are currently being analyzed.
The potential role of copper availability in mediating competition between Types I and II methane-oxidizers
is currently being investigated using laboratory incubations. Natural abundance 13C analyses of porewater
methane and flux methane are currently being conducted by collaborators at UC Irvine.
Papers & Publications; Macalady, J.L., Burton, E.G., and Scow, K.M. 2000. Diversity and population
structure of methane-oxidizing bacteria in rice fields and adjacent natural wetlands. American Society for
Microbiology, Annual Meeting, May 2000, Los Angeles, CA.
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Tyler, S.C., McMillan, A.M.S, Chidthaisong, A., Macalady, J.L., and Scow, K.M. 1999. A multi-faceted
approach using CH4 concentration and delta 13C measurements to quantify and understand CH4 emissions from
a California rice paddy agroecosystem. American Geophysical Union Fall Meeting, December 13-17, San
Francisco, CA.
Macalady, J.L., Dickens, A.F., Scow, K.M., McMillan, A., and Tyler, S.C. 1999. Ecology of methane-
oxidizing bacteria in flooded rice fields and adjacent natural wetlands. Soil Science Society of America,
Annual Meeting, October 31-November 4, Salt Lake City, UT.
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U915635
ATMOSPHERIC ORGANIC NITROGEN - ORIGIN, SPECIATION, AND SIGNIFICANCE
IN GLOBAL MARINE BIOGEOCHEMISTRY
Kimberly A. Mace
Texas A & M University
Objectives/Hypotheses; The goals of this research are to: 1) measure total organic nitrogen (N) and total
inorganic N in rain, bulk, and particle size-separated aerosols; 2) measure specific forms of atmospheric
organic N to include urea and amino acids, and to relate them to total organic N as determined in goal
number 1; 3) compare historical and present day concentrations of organic N in ice core samples in order
to determine the influence of human induced change on organic N totals; 4) evaluate biomass burning as a
potential source of organic N; and 5) evaluate the N isotope signatures of total organic N in order to ascertain
possible sources.
Rationale; Atmospheric organic nitrogen (AON), defined as the water soluble component of total N in
precipitation and aerosols minus the inorganic N forms, ammonium, nitrate, and nitrite, is an under-sampled
component of atmospheric N. At present, there is little data for almost all regions of the world for this
component of the atmospheric N pool, and the species comprising its fraction remain elusive. Furthermore,
the origin of AON in the global atmosphere is not known, and composition differences across hemispheres
are expected, given the disproportionate release of atmospheric pollutants and natural products between the
northern and southern hemispheres. However, little data exist for the southern hemisphere. AON has been
shown to stimulate phytoplankton growth in laboratory culture. Therefore, its significance as a new source
of N, especially in nutrient limited regions of the ocean, deserves attention.
Approach; Sites for the study include an atmospheric sampling tower-based background monitoring station
located at Cape Grim, Tasmania, Australia; an atmospheric sampling tower located on the windward coast
of Oahu, Hawaii; an atmospheric sampling tower located on the Turkish Mediterranean coast; and wet and
dry season samples collected from a biomass burning region in central Amazonia, Brazil. Samples will be
analyzed for total inorganic and organic N. The organic portion of samples will be determined primarily by
ultraviolet (UV) oxidation using a Metrohm 705 UV digestor (Metrohm, Switzerland). Other methods, such
as persulfate digestion, will also be evaluated. Amino acids will be determined by a dabsyl chloride
(DABS-C1) method for high performance liquid chromatography(HPLC). Urea will be determined using
both an ion chromatography (1C) method and a standard colorimetric method. Nitrogen isotopes will be
evaluated on a number of samples and possibly for individual organic species within the organic nitrogen
pool. Ice core samples from Greenland will be analyzed using the methodology above to determine whether
AON is a predominantly anthropogenic component.
Status; I am currently planning a field trip to Ohio State University to analyze ice core samples from
Greenland in the laboratory of Dr. Ellen Mosley-Thompson. This analysis will occur in the summer of 2000.
Also, I am currently determining the analytical uncertainty of both total N and inorganic N methods, and
defining the correct methodology for amino acids by HPLC. I have developed a new urea method for 1C,
and a comparison between the new method and the standard colorimetric technique is being evaluated.
Papers & Publications; Cornell, S., Mace, K., Coeppicus, S., Duce, R., Huebert, B., Jickells, T., and
Zhuang, L.Z. Organic nitrogen in Hawaii rain and aerosol, (in preparation)
Mace, K. and Duce, R. A cation exchange method for urea determination in aerosols and natural waters.
(in preparation)
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U915528
POPULATION GENETICS OF A VERTEBRATE COMMUNITY
IN A PATCHY ENVIRONMENT
Mollie K. Manier
Oregon State University
Objectives/Hypotheses; To describe the degree of genetic differentiation among subpopulations of four
vertebrate species comprising a predator-prey system in a patchy environment. In so doing, I will compare
the population genetics among the four species and within and among trophic levels. I will also estimate the
number of migrants for each species per generation and again compare those estimates among the species
and within and among trophic levels.
Rationale: Habitat degradation and destruction have caused historically continuous species distributions
to become fragmented, resulting in localized patches of suitable habitat within a matrix of inhospitable
terrain. As populations occupying these patches become smaller and more isolated, random genetic drift
increases in relative significance as an evolutionary force that, in the absence of migration, lowers genetic
diversity within a population. Populations with low levels of genetic diversity are more susceptible to
inbreeding depression and consequently, suffer a greater probability of extinction. A clear understanding
of the population genetics of declining species in fragmented habitats is imperative in making management
decisions conducive to the maintenance of a level of genetic diversity that allows for long-term evolutionary
potential and sustainability.
Metapopulation theory has made substantial contributions toward understanding population dynamics of
organisms in fragmented environments. A metapopulation describes a group of populations that is connected
by migration and experiences extinction and recolonization within local patches. Recent work has begun
to focus on the genetics and evolution of metapopulations, but the primary focus thus far has been in the
theoretical realm of modeling and simulation. With a few notable exceptions, relatively little effort has been
spent in describing metapopulation genetics from an empirical standpoint, especially in the context of a
multi-species system.
Approach; The study system of interest consists of two garter snake species (Thamnophis elegans and T.
sirtalis) that prey on the tadpoles and metamorphs of two anuran species (Hyla regilla and Bufo boreas).
All four organisms inhabit lakes, ponds, and flooded meadows within Lassen National Forest in Lassen
County, California. These habitat patches vary widely in size, degree of isolation, permanence, and species
composition. I will use microsatellites to estimate several measures of genetic distance. Since Fst = 1/(1
+ 4Nm), I can use this estimate to calculate Nm, the number of migrants per generation.
Status; In July 1999,1 collected over 1000 tissue samples from approximately 30 subpopulations from all
four species. Seven to eight polymorphic microsatellite primer pairs have been designed or obtained from
the literature for all species except B. boreas, and I am in the process of screening subpopulations of those
species for different alleles at each locus.
Papers & Publications; None at this time.
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U915356
USE OF STABLE SULFUR ISOTOPES IN ICE CORES AS TRACERS
OF PALEOPRECIPITATION SOURCES
Jacqueline L. Mann
University of Maryland
Objectives/Hypotheses; Sources of precipitation to tropical and polar regions vary with time due to
differences in climate conditions caused by alterations in atmospheric circulation. Understanding the origin
of these precipitation sources allows past and present atmospheric circulation patterns to be assessed. Sulfur
isotope measurements of sulfur in ice cores may provide a tool to trace precipitation sources to both tropical
and polar regions. The objectives of this research are two-fold: 1) to explore the use of a 33S/36S internal
standard to increase the accuracy and precision of both sulfur concentration and isotope ratio measurements
on small (< 1 micorgram S) samples, and 2) to examine the utility of sulfur isotopes as a tracer of
paleoprecipitation sources contributed to tropical polar ice cores. We hypothesize that the sulfur isotopic
composition of sulfur in ice cores records the primary paleoprecipitation sources, as the primary source
isotopic composition is expected to remain constant with changes in air temperature and along air mass
trajectories, unlike d!80 and dD.
Rationale: Sources of precipitation to tropical and polar regions vary with time due to different climate
conditions that are likely caused by climate alterations in atmospheric circulation. Currently, deuterium
excess (d=dD - 8dl8O) is the method used to identify paleoprecipitation sources to ice cores. The excess
reflects the kinetic fractionation occurring during non-equilibrium processes (evaporation above the ocean
surface or snow formation) and is represented by the deviation from the meteoric water line. Hence, the
excess values are controlled by the temperature of evaporation in the moisture source areas. High excess
values are the result of moisture derived from warm subtropical oceanic regions while lower excess values
are representative of moisture derived from cooler oceanic regions.
Sulfur isotopes may provide an additional tracer tool of precipitation sources. These isotopes, unlike dD and
d!8O, are not effected by air-temperature; thus, sulfur isotopic composition of precipitation is expected to
remain constant with changes in temperature and along air mass trajectories. Hence, they may record the
primary paleoprecipitation sources to these regions assuming those sources of precipitation today were also
active in the past.
Approach: The approach to be used in this research starts with exploring a new method to increase the
accuracy and precision of both concentration and isotopic ratio measurements of sulfur. Using a 33S/36S
internal standard allows the calculation of a fractionation factor, which will be used to correct the 32S/34S
ratio yielding highly precise ratios that are as accurate as the internal standard itself. Once the method has
been optimized the method will be used to measure sulfur isotopes in ice core material. These sulfur isotopes
in conjunction with geochemical evaluative techniques will be used to: 1) characterize current precipitation
sources that influence the d34S values of precipitation recorded in ice cores, 2) identify the current
seasonal—summer and winter—shifts in d34S to determine the primary contributors of precipitation today,
and 3) characterize the d34S shifts through the Younger Dryas where climate was distinctly different to
assess S isotopes as a tracer of paleoprecipitation sources.
Status; A proposal of this research has been drafted and experimental work on the new sulfur measurement
technique is underway. Analysis of ice .core material is set to begin this winter.
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Papers & Publications; Mann, J.L.,O'Connell, M.E., Prestegaard, K.L., and Bahlke,J.K. 2000. Natural
sources of sulfur in a coastal plain stream, (in preparation)
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915191012
BIOLOGICAL DENITRIFICATION OF NITRATE CONTAMINATED
GROUNDWATER IN A MEMBRANE BIOREACTOR
Bruce O. Mansell
University of California, Davis
Objectivcs/Hvpotheses: The overall objective of this project is to develop an efficient and effective
treatment process for the remediation of nitrate contaminated groundwater.
Rationale: Nitrate contaminated groundwater has been documented worldwide. Because ingestion of high
levels of nitrate may cause negative effects on human health, efficient and effective removal processes are
needed. Biological denitrification is an attractive treatment option because nitrate is efficiently and
selectively removed byconversion to nitrogen gas. However, typical process configurations are limited by
the direct contact between the denitrifying organisms and the product water. Sloughed cells and reaction
products are imparted to the product water and must be removed by cumbersome polishing treatment steps.
Approach; Studies will be conducted to develop a novel membrane bioreactor. In the reactor, the
denitrifying culture and contaminated water are separated by a microporous membrane. Nitrate is removed
by molecular diffusion through the membrane and into the culture. The membrane serves as a barrier to
prevent contamination of the product water. The studies will be conducted in two phases. In phase one, a
heterotrophic culture will be used in the reactor. The specific objectives will be to determine the efficiency
of the system and to determine the validity of a nitrate removal mathematical model. In phase two,
experiments will be conducted using autotrophic organisms that use hydrogen gas as an energy source. The
specific objectives will be to identify the microbial population in the system using molecular techniques,
determine the stability of the system, and the efficiency of the system.
Status: Phase one has been completed thus far with promising results. Phase two is partially complete.
Identification of the population has been completed. The system is currently being operated to determine the
stability and efficiency.
Papers & Publications; Mansell, B.O. and Schroeder, E.D. 1999. Biological denitrification in a continuous
flow membrane reactor. Water Research, 33(8): 1845-1850.
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U915548
MODELING REGIONAL SCALE OZONE SENSITIVITY TO PRECURSOR EMISSIONS
WITH A FUEL-BASED MOTOR VEHICLE EMISSION INVENTORY
Linsey C. Marr
University of California, Berkeley
Objectives/Hypotheses: The major objectives of this research are to develop an improved understanding
of regional scale ozone sensitivity to volatile organic compounds (VOC) and oxides of nitrogen (NOX)
emissions and to identify patterns in ozone time series observations that can be used to diagnose regional
scale transport and VOC v. NOX sensitivity.
Rationale; Although atmospheric scientists have gained a more detailed understanding of tropospheric
ozone chemistry in recent years, it is still not obvious where or by how much to control VOC and NOX
emissions to achieve lower ozone levels. In many locations, ozone is a regional scale problem; transport of
ozone and its precursors from densely urbanized areas affects ozone levels at distant downwind sites.
However, most air pollution modeling has been limited to the urban scale.
Approach; I am using an Eulerian photochemical airshed model to gain insight into ozone formation on
a regional scale in Central California. I obtained meteorological data and pollutant concentrations, which
are used as input to the model, from a large field study in the San Joaquin Valley. To evaluate ozone
sensitivity to precursor emissions, it is crucial that the emission inventory be accurate. Official estimates of
motor vehicle emissions, the main anthropogenic source of VOC and NOX emissions in most populated areas,
have been shown to be inaccurate, so the first step of my research has been to create a improved estimates
of motor vehicle emissions. The revised motor vehicle emission inventory takes into account fuel
consumption data, fuel-based emission factors from tunnel studies of on-road vehicles, and traffic count data
specific to the day of week, hour of day, and vehicle class. I am using the model to examine the causes of
patterns in ozone observations, such as a shift in the time of ozone peak at downwind sites, differing shapes
of diurnal ozone profiles, and weekday v. weekend differences in ozone. These patterns may be indicators
of regional scale transport and VOC v. NOX sensitivity.
Status; I have developed a revised inventory of motor vehicle emissions. Compared to the official motor
vehicle emission inventory, the revised inventory contains higher VOC emissions and lower NOX emissions.
As a result of the improved estimates of motor vehicle emissions, model performance has improved, with
higher predicted ozone in urban areas, suggesting that these areas are VOC-sensitive. I expect to complete
this project in the middle of 2001.
Papers & Publications; None at this time.
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U915195
THEORY AND PRACTICE OF PUBLIC MEETINGS
Katherine A. McComas
Cornell University
Objectives/Hypotheses; This project seeks to understand how government-sponsored public meetings
influence individuals' risk perceptions and source credibility judgments during local environmental
problems. In addition, it examines how public agency officials conducting the meetings judge their
effectiveness as methods for public participation. Finally, it investigates the extent to which citizens and
officials are satisfied with public meetings as methods for involving citizens in environmental planning. The
research is exploratory and produces results applicable to individuals conducting and participating in public
meetings, as well as to researchers seeking to understand more fully potential impacts of public participation.
Rationale; Public meetings are widely used, frequently criticized, and notably neglected by researchers.
Although many people have opinions or "feelings" about how effective or successful public meetings are
as tools for risk communication and public participation, empirical research on the topic is sparse.
Consequently, questions regarding their impacts in a given risk situation remain either largely unanswered
or unsubstantiated by research.
Approach; To explore these issues, a field study was conducted in three upstate New York communities
facing environmental problems and using government-sponsored public meetings as at least one form of
public participation. Data collection included brief historical analyses of the communities, observations of
public meetings, pre- and post-meeting surveys of citizens attending public meetings, pre- and post-meeting
surveys of residents living near the environmental problems, interviews with officials conducting public
meetings, and a review of local newspaper coverage of the public meetings.
Status; The research is complete. The dissertation will be finished and the Ph.D. awarded in August 2000.
Papers & Publications; McComas, K.A. Public meetings about local waste management problems:
comparing participants to non-participants. Environmental Management (accepted)
McComas, K.A. 1999. What makes a successful public meeting? Interviews with Risk Managers. Paper
presented at the Society for Risk Analysis Annual Meeting, Atlanta, GA.
McComas, K.A. and Trumbo, C.T. 1999. Application of Meyer's credibility index in environmental health-
risk controversies. Paper presented at the National Communication Association Annual Convention,
Chicago, IL.
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U915327
BIOTIC AND ABIOTIC TRANSFORMATION OF CARBON TETRACHLORIDE
DURING MICROBIAL mON REDUCTION
Michael L. McCormick
The University of Michigan
Obj ectives/Hypotheses; The objective of this research is to investigate the role that iron reducing bacteria
play in transforming carbon tetrachloride (CT) in anaerobic environments. The specific hypotheses tested
are: I) iron reducing bacteria are capable of directly mediating the reductive transformation of CT through
co-metabolic processes, and 2) iron reducing bacteria can indirectly drive dehalogenation reactions through
the formation of reduced mineral species, which react abiotically with CT.
Rationale; Carbon tetrachloride (CT) is the most commonly encountered groundwater contaminant in the
United States. Research into the anaerobic biodegradation of CT has focused primarily on co-metabolic
transformation mediated by methanogens and sulfate reducing bacteria. Although iron reducing bacteria are
ubiquitous in the subsurface and ferric iron is one of the most abundant electron acceptors in anaerobic
aquifers, the ability of these bacteria to mediate reductive transformations remains largely unexamined.
Nevertheless, thermodynamic calculations indicate that CT dehalogenation should occur readily under iron
reducing conditions. A number of biogenic redox active molecules are found in iron reducing bacteria that
could play a role in CT reductive dehalogenation. Additionally, the ferrous iron produced by microbial iron
reduction is known to be a strong reductant when adsorbed to the surfaces of metal oxides. This suggests
that iron reducing bacteria could promote CT transformation via both biotic and abiotic mechanisms.
Approach; The kinetics of CT transformation are being studied in batch reactors containing either cell
suspensions of the dissimilative iron reducing bacteria, Geobactermetallireducens, or slurriesof biologically
reduced iron oxide particles (the principle mineral product of iron reduction by this bacteria is the mixed
valence iron oxide magnetite, Fe3O4). CT and volatile products are monitored by gas chromatography using
flame ionization (FID) or electron capture (ECD) detectors. To help determine the fate of CT in these
systems, 14C labeled CT is used in parallel batch reactors. Identification and quantification of radiolabeled
dissolved products is achieved using high performance liquid chromatography (HPLC) coupled with a
radioisotope detector.
Status: Experiments on the kinetics of cell and mineral mediated reactions are finished. Mass balances for
product formation in both the biotic and abiotic systems have recently been obtained. Current work on
describing the biogenesis of the reduced iron oxide particles is nearing completion.
Papers & Publications; McCormick, M.L. and Adriaens, P. 2000. Transformation of tetrachloromethane
in a defined iron reducing culture: relative contributions of cell and mineral mediated reactions. Extended
Abstracts, 219th American Chemical Society National Meeting, March 26-30, San Francisco, CA, 40:138-
141.
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U915619
MODELING EFFECTIVE LAND USE DECISIONS FOR URBAN AREAS
Althea L. McCoy
Clark Atlanta University
Objectives/Hypotheses; The continuation of poor land use decisions will result in ecologically and
economically fragile cities (and rural areas) that negatively affect the quality of life of residents.
Rationale: Cities across the United States are facing a myriad array of problems. The average commute
time in many urban areas is 30 minutes to and from work or school; smog alerts are released far too often;
public housing is in decay; ground level ozone persists in concentrations harmful to human health; and there
are increasing numbers of "environmentally unsound" developments. Many of these problems have resulted
from rapid growth and development and poor land use decisions. While urban areas are ecologically the most
efficient forms of human spatial organizations, they are simultaneously among the most polluted. Con-
sequently.cities find themselves in very tenuous situations with these conditions affecting their environments
and the quality of life of residents. Accordingly, it is imperative that government officials, environmentalists,
policy makers, and individual citizens focus on cleaning-up and revitalizing our cities. What endeavor could
be more eminently worthy and necessary—more deserving of our national attention, expertise and
resources—than that of revitalizing America's urban areas and ensuring healthy and sustainable com-
munities? Accordingly, it is imperative to understand the process of and the factors affecting land-use
decisions. Additionally, it is important to determine how interested parties can more effectively protect
scarce environmental resources and promote sustainable development.
Approach; The following questions will guide the research: 1) How are land-use decisions made in various
urban areas? What factors are involved? Are these decisions driven by local public officials, urban planners,
environmentalists or powerful business interests? According to the theory of market externalities, land-use
and development decisions are driven by business interests with public officials and environmentalists
playing a secondary role. Pursuant to this theory, a particular developer decides if it will create a mixed
business/residential development with "greenspace" and walking trails or build a strip mall with plenty of
paved parking in the middle of a "greenfield." 2) What new scientific/technological practices or
environmental principles could make it easier to produce more effective land-use decisions (smart growth,
sustainable development, etc.)? To what degree are these principles/practices being utilized in urban areas?
What, if any, specific resources do local governments and business interests need to implement innovative
practices for protecting the environment? 3) What is a working definition of sustainable development? (I am
interested in seeing a definition that goes beyond the goal of maintaining a certain level of a resource to
increasing the availability of the resource for future generations.) Because of the nature of the research
proposal, it will be advantageous to utilize the case study method. I will select four to five representative
urban areas (with varying sizes, populations, types of environmental problems, strength of economy, etc.).
Status; After completing the research design in April 2000,1 am currently collecting data, reviewing the
literature, and performing case study analysis.
Papers and Publications; None at this time.
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U915176
CONTROLLING THE FOREST UNDERSTORY: WILD MUSHROOM
POLITICS IN CENTRAL OREGON
Rebecca J. McLain
University of Washington
Obi ectives/Hvpotheses; My project's objective was to illustrate how techniques of disciplinary power are
being used to extend and solidify nation-state control over forest understory products on national forest lands
in the Pacific Northwest.
Rationale; French social theorist, Michel Foucault (1978; 1979; 1980), argues that the rapid expansion of
state influence over people's everyday lives is due to the widespread application of disciplinary power
techniques. Disciplinary power seeks to remold and reshape individuals to behave in certain ways of their
own volition. It works through the application of a combination of techniques that fix individuals socially
and in space: 1) assignment of individuals or groups into categories; 2) enclosure and separation of indi-
viduals and groups from each other; 3) construction of a documenting apparatus that links individuals to
specific acts; 4) creation of a "pan-opticon" space that permits a small number of observers to monitor a
large number of individuals simultaneously; and 5) development of professional categories through testing
and licensing procedures. Foucault's work focuses on the application of disciplinary power in the domains
of medicine, public health, and criminal justice. Recent work by cultural geographers suggests that similar
processes are also at work in the natural resource management arena. Bryant (1997) and Neumann (1998),
for example, demonstrate the key role disciplinary power played in enabling the British empire to extend its
claims to resources in Asia and Africa. Historical geographers have also documented the use of disciplinary
power by the American state to control the Lakota nation (Hannah, 1993) and migrant farm workers in
California (Mitchell, 1996).
Approach: I used a political ecology approach using ethnographic case study methods, including partici-
pant observation, semi-structured interviews, and archival research. I utilized standard qualitative software
(Atlas-TI) to code and analyze my interviews and field notes. The Sisters Ranger District on the Deschutes
National Forest constituted my primary field site.
Status; Field work is completed; the draft is scheduled for completion in mid-July 2000.
Papers & Publications: McLain, R.J. and Jones, E.T. 1998. Participatory non-wood forest products
management: experiences from the Pacific Northwest, USA. In: Lund, H. Gyde; Brita Pajari, and Minna
Korhonen (eds.). Sustainable Development of Non-Wood Goods and Benefits from Boreal and Cold
Temperate Forests. Proceedings of the International Workshop, Joensuu, Finland. January 18-22, 1998.
European Forest Institute Proceedings No. 23.
McLain, RJ. and Jones, E.T. 1997. Challenging "community" definitions in sustainable natural resource
management: the case of wild mushroom harvesting in the USA. International Institute for Environment and
Development. Sustainable Agriculture Programme. Gatekeeper Series No. 68.
McLain, R.J. and Jones, E.T. Expanding NTFP harvester/buyer participation in Pacific Northwest forest
policy, (submitted to Journal of Sustainable Forestry, in review)
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U915652
LARGE-SCALE MOVEMENT PATTERNS AND GENETIC STRUCTURING
AMONG PUMA POPULATIONS IN A FRAGMENTED LANDSCAPE
Brad H. McRae
Northern Arizona University
Objectives/Hypotheses; My main objective is to use noninvasive genetic analysis techniques to determine
whether isolation has affected genetic structuring of puma (Pumaconcolor) populations in the southwestern
United States and in northwestern Mexico. I will also use these analyses to construct models of how natural
and anthropogenic habitat fragmentation affect gene flow between populations of pumas. Secondary
objectives, in cooperation with other researchers, include partial replication of the above study objectives
with bobcats, development of scented hair snares for noninvasive DNA sampling among felids in temperate
and tropical habitats, and addressing separate questions of current and historic genetic structuring among
jaguar populations in the U.S.-Mexico borderlands.
Rationale: Highly mobile species such as pumas often exhibit rates of gene flow sufficient to limit the
accumulation of genetic differences between adjacent subpopulations. However, genetic substructure may
exist if populations have been fragmented by recent habitat alterations or by prehistoric barriers to gene flow,
and genetic variation can be lost rapidly in small, isolated populations of felids. Empirical studies are needed
to validate and parameterize models of habitat connectivity and large carnivore movement over large areas,
and related population viability and metapopulation models. Movement of large carnivores has received
considerable attention as a process to be conserved, and several conservation organizations active in the
southwestern United States have specifically focused on the puma's need for habitat connectivity in their
large-scale conservation planning efforts. Our focal region, known as the Madrean Archipelago or "sky
islands," consists of forested mountain ranges surrounded by Sonoran and Chihuahuan desert. It is of
particular conservation importance because it is an area of high species diversity, and constitutes the only
high elevation connection between major floristic and faunal realms of the United States and Mexico.
Within the region, rapid development is isolating habitat islands, and conservation organizations are in
critical need for information on how to maintain animal movement corridors between them.
Approach; I will obtain DNA samples from hair collected from scented hair snares, from feces collected
in the field, and from hunter-killed cats. I will analyze these samples using 16-20 feline microsatellite
markers. I will then relate genetic distances between populations to geographic distances and landscape
features using a models of habitat conductivity parameterized for each species.
Status; I have collected approximately 170 puma and 80 bobcat tissue samples from the past year's hunting
and trapping season, and have access to historic and current jaguar tissue and bone samples from Arizona
and Sonora. Development and testing of hair snares is proceeding well, with very promising results from
a range of habitat types. Sixteen microsatellite loci are amplifying well.
Papers & Publications: None at this time.
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U915429
MORMON AND CATHOLIC PERSPECTIVES ON NATIONAL FOREST MANAGEMENT
Nancy L. Menning
University of Wisconsin", Madison
Objectives/Hypotheses: To describeand interpret widespread religious beliefsystemsin the western United
States with respect to the implications of those beliefs for land use and land management activities.
Rationale; Public land managers have long expressed concern for local communities living near public
lands. Historically, that concern has focused on economic variables such as employment stability and
contributions to the local tax base. More recently, land managers have more clearly expressed a desire to
augment ecological and economic criteria for natural resource decision-making with greater attention to
socio-cultural factors. Thus, managers and researchers have explored sense of place, emotional attachment
to place, local culture and custom, etc. Religion is a foundational element of culture; for faithful people, it
provides a symbolic understanding of their own human nature and of their roles and responsibilities in the
social and biophysical world in which they live. This project contributes to an existing literature linking
religion and the environment in four ways: 1) it emphasizes the grounded, day-to-day activities of rural
people in their local places; 2) it collects qualitative data in the words of the study participants; 3) it focuses
on religious faiths (Mormonism and Catholicism) that are numerically dominant in the western United
States; and 4) it recognizes the complex character of the religion-environment linkage, simultaneously
involving environmental impacts on religious belief (through experience in God's creation) and religious
impacts on the environment (through religiously motivated action).
Approach: This project, conducted among Catholic and Mormon populations in eastern Arizona, entails
three overlapping phases: 1) establishment in the field setting; 2) focused exploration of linkages between
religious beliefs and local land-use activities; and 3) qualitative data analysis, interpretation, and writing.
In the first phase, the researcher developed an understanding of local resource management issues through
participant-observation, involvement with local resource management entities and activities, evaluation of
local newspaper coverage, attendance at relevant public hearings, etc. Simultaneously, the researcher
established a relationship with the targeted faith communities, worshiping with them and discussing
scripture, doctrine, and tradition with local members, ministers, and designated missionaries. In the second
phase, local faith community members were engaged in a discussion linking their religious beliefs and their
actions and perspectives on local land use through continued participant-observation, informal interaction,
and interviews. Finally, in the third phase, fieldnote entries and transcriptions of interviews and study group
discussions are analyzed to develop an interpretation of religious dimensions of land-use practices,
describing the religion-environment linkage as both a reflection of and a response to the world in which we
live.
Status: Data collection in the field commenced in July 1998 and continued through December 1999.
Qualitative data analysis, interpretation, and writing will continue through June 2001.
Papers & Publications; None at this time.
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U915177
THE INFLUENCE OF SURFACE WATER CONSTITUENTS ON THE PHOTOCHEMICAL
TRANSFORMATION OF NON-POINT SOURCE POLLUTANTS
Penney L. Miller
The Ohio State University
Objectives/Hypotheses; This project will ascertain the potential for the transformation of non-point source
pollutants (NPSPs) by photochemical processes in shallow surface waters. Specific objectives include: 1)
the evaluation the direct photolytic contribution of pollutant transformation in water samples from wetlands
and a eutrophic lake, and 2) the characterization of the photochemical properties of water constituents and
the determination of their influence in the indirect photochemical transformation of NPSPs.
Rationale; The current understanding of photochemical processes in surface waters and in particular,
wetlands, is at best empirical (i.e., a black-box approach). Several physical characteristics of these systems
may facilitate photochemical reactions. Probing these reactions for constituent-promoted reactions will
provide information on how naturally occurring photosensitizers may enhance NPSP transformation. By
assessing the photochemical contribution to the degradation of select contaminants in various surface waters,
this research will provide information on how the quality of surface waters may be improved.
Approach: The transformation reactions of "model" NPSPs in various types of surface waters under diver-
gent environmental conditions (mid-latitudes vs. polar) was studied. Target compounds were chosen on the
basis of their ubiquitous use in Ohio agriculture (carbaryl and alachlor) or global dispersion (e.g., chlorinated
aromatics in Antarctic water/soil/organisms). Sampling sites were chosen because of their perceived
reactivity (i.e., wetlands in temperate regions and Antarctic and Arctic surface waters susceptible to thaw
during the summer season). One wetland site in Ohio was selected for study: Old Woman Creek Estuarine
Reserve (OWC). Antarctic sites included Pony Lake (PL), Ross Island, a shallow Antarctic lake, Lakes
Hoare, Fryxell, Bonney in the Taylor Valley, and McMurdo Sound of the Ross Sea. NPSP contamination
occurs in the wetland site from agricultural run-off, while atmospheric transport accounts for much of the
contaminant loads in Polar regions. Identification (e.g., UV/VIS, fluorescence, HPLC, TOC) and isolation
(e.g., ultrafiltration and XAD extraction) of photoreactive water constituents were performed. Target
compounds were irradiated in either the raw water or reconstituted isolates (natural organic matter (NOM)
obtained from the OWC, PL, or an International Humic Substance Society standard) using either a mercury
or xenon arc lamp in a "merry-go-round" reactor or sunlight. Light intensity was measured with chemical
actinometers. Samples were withdrawn periodically from reactions, and pollutant concentrations were
monitored via HPLC, GC/ECD, or GC/MS. The relative and overall degradation rate constants were
determined through kinetic analysis. The contributions to reactions from different indirect photolytic
processes were probed using transient specific quenchers and altering reaction conditions such that certain
processes were favored.
Status; Water samples have been collected from all sites and have been assessed for some photophysical
properties (e.g., UV/VIS, fluorescence). Batch photolytic studies were performed with insecticide carbaryl
and herbicide alachlor in OWC water and hexachlorobenzene in PL water and Toolik Lake Water (an Arctic
surface water provided as gift to our lab by Dr. Mike Perdue of Ga. Tech.). Analysis of the samples revealed
two major photoreactive constituents (i.e., NOM and nitrate) in the wetland water and one (i.e., NOM) in
the Antarctic and Arctic surface water. In most cases, indirect photolytic mechanisms were found to enhance
NPSP transformation. Moreover, the pesticide carbaryl demonstrated a range of susceptibility for direct
photodegradation at different environmentally relevant pHs. Overall, the results showed that natural water
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constituents play a varied role in mediating the transformation of organic contaminants. This research is to
be completed by June 2000.
Papers & Publications; None at this time.
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U915621
MOLECULAR MONITORING OF MICROBIAL POPULATIONS DURING
BIOREMEDIATION OF CONTAMINATED SOILS
DeEtta (Dee) K. Mills
George Mason University
Objectives/Hypotheses: This research uses molecular techniques to examine the microbial population
dynamics (changes) during the bioremediation of petroleum contaminated soils in laboratory bioreactor
microcosms and the impact nutrient enhancement has on the microbial community structure.
Rationale: One type of bioremediation is the enhancement, through nutrient addition, of natural microbial
processes that degrade or detoxify hazardous wastes. However, many criticize the inability to directly assess
the biotic processes during bioremediation. Molecular techniques are effective tools capable of probing
complex natural soil or sediment microbial communities in situ. To be useful as a remediation monitoring
tool, however, molecular techniques need to contribute information about the biotic processes that are not
readily obtained by traditional microbiological methods. Direct nucleic acidanalyses can provide immediate
data, greater resolution of the whole microbial community (both the aerobic and anaerobic populations), and
help answer questions that have not been possible with standard microbiological culture based methods.
Therefore, with a more thorough understanding of the microbial community and its dynamics, improved
expectations and optimization of bioremediation processes will be possible.
Approach; Natural occurring base substitutions, deletions or insertions within the nucleic acid sequences
provide molecular markers that can be used to distinguish between different genomes. Microbial community
profiles based on the restriction enzyme site polymorphisms ornatural occurring sequence differences in the
16S ribosomal DNA (rDNA) genes produce different sized DNA fragments or fingerprints. Therefore, this
research uses microbial community DNA fingerprints to monitor the temporal microbial dynamics and the
impact of nutritional amendment during the bioremediation process. Briefly, whole soil community gen-
omic DNA was extracted from bioreactor slurry soil samples using a modified bead beating protocol. The
polymerase chain reaction (PCR) was used to amplify 16S rDNA with fluorescent-labeled nucleotides or
fluorescent-labeled universal primers. The purified PCR products were either: a) subjected to restriction
enzyme digests (restriction fragment length polymorphisms-RFLP and fluorescent terminal length
polymorphisms-FTLP); or b) directly loaded onto a gel (amplicon length heterogeneity-ALH). Resolution
of the fingerprint patterns was done on the Perkin Elmer ABI Prism 377 fluorescent DNA sequencing
instrument. These three fluorescent-based methods were assessed for their ability to screen the complexities
of the microbial community. To probe the microbial diversity of the samples, cloning of the PCR products
and subsequent DNA sequencing of these clones will determine which species are present at any one time
point.
Status; All experiments (DNA extractions, PCR, DNA fingerprinting, cloning and DNA sequencing) are
completed. Data analyses are now in progress and all work should be completed by summer 2000.
Papers & Publications; Mills, D.K., Fitzgerald, K., Gillevet, P.M., and Litchfield, C.D. 1999. Molecular
monitoring of microbial populations during bioremediation of contaminated soils. In: B.C. Alleman and
A. Leesons, eds. Bioreactor and Ex Situ Biological Treatment Technologies S(5):143-148, Battelle Press,
San Diego, CA.
Mills, D.K., Fitzgerald, K., Litchfield, C.D., and Gillevet, P.M. Microbial community stability or dynamics
during bioremediation of petroleum-contaminated soils? A Comparison of Techniques, (in preparation)
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U91S584
INVESTIGATION OF WATERBORNE MICROSPORIDIA
Jeffrey T. Mital
John Jay College
Objectives/Hypotheses; The proposed research is designed to develop a simple and efficient method for
the routine detection of waterborne microsporidia and to apply this method to investigate the occurrence of
microsporidia in surface water.
Rationale: Microsporidia are opportunistic protozoans that have the ability to infect humans and are of
particular concern to the immuno-compromised, primarily causing intestinal illness. Clinical research has
improved diagnosis and treatment of microsporidiosis. However, there is an urgent need for research aimed
at identifying the sources of infection and improving methods for routine testing of these sources.
Preliminary research indicates ingestion of contaminated water as a possible mode of transmission, but little
research has been performed to verify this hypothesis. Their protective spore and small size make
elimination of microsporidia from drinking water difficult by traditional chlorination and filtration
techniques. These factors have prompted the U.S. EPA to target microsporidia as one of eight "emerging
pathogens of concern."
Approach: The proposed technique concentrates microsporidia spores by filtration and detects their pre-
sence through PCR amplification of the gene that codes for a small subunit of ribosomal RNA in
microsporidia. Submicron filters of different material, construction, and pore size are being tested to
determine the most efficient filter for capture and recovery of spores. Various methods are being evaluated
to determine the most effective means of extracting and isolating amplifiable DNA from \vithin the tough
spore. Primers are used to amplify DNA from most species of microsporidia that are infectious to humans.
The refined technique will be used to test surface water samples for the presence of microsporidia. The
specific species present may then be determined by a combination of methods. Each species present will
result in an amplification product of different lengths, ranging from 410 to 433 bp. By employing Perkin
Elmer's ABI Prism 310 Genetic Analyzer, the length of the PCRproduct can be determined within one base
pair. Species confirmation will be accomplished by sequencing the PCR product.
Status; Currently, DNA extraction, isolation, and amplification techniques have been refined and evaluated
using water samples spiked with two species of microsporidia. Work is presently being conducted to assess
the efficiency of various PES filters for capture and recovery of spores. Upon completion of the methods
evaluation, surface water samples may be analyzed for the presence of microsporidia.
Papers & Publications: None at this time.
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U915248
FOREST MANAGEMENT AND FRUIT HARVEST IN AMAZONIAN FOREST
Susan M. Moegenburg
University of Florida
Objectives/Hypotheses; The goal of this project is to determine the indirect ecological impacts of managing
tropical forests for non-timber forest products (NTFPs) and harvesting NTFPs. We conduct this research
with the objective of providing data that form an ecological basis for sustainable NTFP management and
harvest.
Rationale; As tropical forests are increasingly impacted by human activities, it is imperative to discover
sustainable means of merging forest use with biodiversity conservation. This study provides the first
experimental test of the ecological impacts of harvesting fruit from tropical forests.
Approach; Previous results are discussed below. Recent work has focused on fruit as nutrient sources in
flooded forest ecosystems. I conducted a fruit decomposition study to evaluate the loss of nutrients from
decomposing fruits. Mesh bags containing 50 fruits were placed on the submerged forest floor. At 2-day
intervals (months 1 and 2) and 2-week intervals (months 3 and 4), bags were removed and fruits were dried.
Fruits were then ground and analyzed for organic matter, nitrogen, and phosphorus.
Status; Previous results show that both management and fruit harvest have significant ecological impacts.
Forest management for the palm Euterpe oleracea simplifies forest structure, lowering canopy height,
canopy density, stem density, and basal area. These vegetation changes impact the understory bird
community. Managed forests are dominated by canopy-dwelling frugivorous and omnivorous species,
whereas non-managed forest contains more understory, insectivorous species. Furthermore, harvest of all
available ripe fruit results in declines in frugivorous bird species diversity, abundance, and time spent
foraging. Such results can be incorporated into management plans to limit harvest at levels that also
maintain animal communities.
Papers & Publications! Moegenburg, S.M. 2000, Sustainable harvest of non-timber forest products: a case
study from Amazonian Brazil. Society for Conservation Biology annual meeting, Missoula, MT.
Moegenburg, S.M. 1999. Managing for non-wood forest products: ecological impacts of palm forest
development in the Amazon estuary. Society for Conservation Biology, College Park, MA.
Moegenburg, S.M. Pespectivas ecologicas sobre la cosecha de productos forestales no maderables
(Ecological perspectives on sustainable harvest of non-timber forest products). In: Desarrollo sostenible
en la Amazonia: mito o realidad (Sustainable development in Amazonia: myth or reality)? Hiraoka, M. and
Kahn, F., eds. (in press)
Moegenburg, S.M. and Jardim, M.A.G. Utilization of a9ai (Euterpe oleracea) fruit and fruit patches by fruit-
eating birds. In: Caxiuana: biodiversidade & desenvolvimento sustentavel (Caxiuana: biodiversity &
sustainable development). Lisboa, P.L.B., ed. Museu Paraense Emilio Goeldi, Para, Brazil, (in press)
Moegenburg, S.M. Ecological effects of managing for the non-timber forest product Euterpe oleracea. (in
preparation)
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Moegenburg, S.M. and Levey, D.J. Frugivore responses to human palm fruit extraction in Amazonian
floodplain forest, (in preparation)
Moegenburg, S.M., Newman, R., and Castelo Branco Pina, A. Palm regeneration in Amazonian floodplain
forest, (in preparation)
Moegenburg, S.M. Spatial and temporal variation in hydrochory in Amazonian floodplain forest, (in prepar-
ation)
Moegenburg, S.M. and Newman, R. Ecological adaptation of palm seed morphology, (in preparation)
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SURFACED ENHANCED RAMAN SCATTERING FROM SILVER FRACTAL
AND BIOLOGICAL SPECIMEN
Joseph R. Montoya
New Mexico State University
Objectives/Hvpotheses: Many environmental problems can be solved with a better analysis tool. The
detection process for biological pollutants/contaminants is in need of a new analysis tool to better serve the
fight against disease and destruction of the environment. The ability to see very small amounts of pollutants/
contaminants can revolutionize the current methods of containing and controlling these pollutants. Surfaced
enhanced Raman Scattering (SERS) and Morphology Dependent Resonances (MDR) have been shown to
increase in signal when in the presence of silver nanostructure materials. We know that these nanostructure
materials have a fractal geometry. Our group grows silver nanostructure materials and applies this known
optical signal increase to a biological specimen. The signal increase will give a "fingerprint" of the bio-
logical specimen and we can use this to identify it in the future. The most important feature of this project
is the low power from which the original pump beam comes from; the original power of the laser is only 20
mW. This is not much more that a hand held laser pointer.
Rationale: SERS effect has been demonstrated with many molecules adsorbed on specially prepared silver
surfaces; this effect is explained by Moskovits as an electromagnetic effect. Later, these silver surfaces
where replaced by colloidal silver. When the colloids aggregated, a fractal structure was observed. In 1999,
Armstrong put these silver colloids in Microcavities (MDRs), which, in turn, increased the already observed
signal. The next step is to try and observe an increase in a biological sample adsorbed on the silver
nanostructure material.
Approach; Using various techniques, based on the Lee Mieser method, silver nanostructure samples were
prepared. These samples are then combined with biological specimen in an effort to obtain a Raman spectra
unique to the biological sample. The Raman spectrum is obtained with a 632 nm HeNe (20mW) cw pump
laser and a CCD camera mounted to a spectraPro-3001 spectrograph.
Status: Correct colloidal particles made and currently doing SERS analysis.
Papers & Publications; None at this time.
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U915434
REDOX CHANGES IN THE GROUND WATER ENVIRONMENT: IMPLICATIONS
FOR NATURAL ATTENUATION OF CHLORINATED ETHENES
Angela M. Moore
University of California, Davis
Objectives/Hypotheses: Evaluate the ability of native microorganisms to biodegrade chlorinated ethenes
under changing redox conditions in dynamic groundwater systems.
Rationale: Chlorinated solvents and their transformation products are the most common organic
contaminants in U.S. groundwater supplies (McCarty, 1996). Potential use of natural attenuation to re-
mediate chlorinated contaminants requires an understanding of the subsurface processes affecting these
compounds. In particular, the rate and extent of chlorinated ethene degradation depends strongly upon the
redox status of the groundwater system. Under anaerobic conditions and in the presence of a suitable
electron donor, chlorinated ethenes are subject to sequential reductive dechlorination according to the
sequence PCE is converted to TCE, TCE to DCE, DCE to vinyl chloride (VC), and finally VC is degraded
to ethene. Highly toxic vinyl chloride can be oxidized under aerobic or iron reducing conditions and can be
degraded by various co-metabolic processes. Seasonal fluctuations in the redox potential of shallow
groundwater at the Yolo County Municipal Landfill site may strongly affect the potential for contaminant
biodegradation at the site. The use of separate anaerobic and aerobic systems has been used to treat
chlorinated compounds in engineered systems, but the effects of fluctuating redox conditions on
biodegradation in dynamic, shallow aquifer systems have not been fully evaluated in published studies.
Kinetic parameters for biodegradation rates, as well as lag times and induction times have not been well
documented for subsurface microbial populations subject to changing redox conditions.
Approach: Experimental columns have been set up to obtain kinetic parameters under aerobic, anaerobic,
and fluctuating redox conditions. Columns have been seeded with microorganisms from the contaminated
site. Contaminant and electron acceptors are controlled in the influent and measurements are made at the
outlet of the columns.
Status: Experimental setup and design is complete and the columns are being exposed to PCE under nitrate
reducing conditions. Major data collection for this system will begin at the end of May and will continue
through the summer; conditions will be changed when a steady state is reached. Intensive work on the
aerobic system will begin in June and continue through the summer.
Papers & Publications: None at this time.
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U915424
ADAPTIVE OPTIMAL CONTROL AND THE REDUCTION OF UNCERTAINTY IN
MANAGING A GEORGIA PIEDMONT FOREST FOR MULTD7LE WILDLIFE OBJECTIVES
Clinton T. Moore
University of Georgia
Objectives/Hypotheses; My objective is to develop a forest management decision support system in which
uncertainty about how certain wildlife resources respond to decision actions is formally recognized and
reduced through the decision making process. I want to demonstrate how management decisions may be
optimally made in the face of uncertainty. Models developed for this work will accommodate partial system
measurement and spatially-explicit system dynamics, and decision policies will demonstrate trade-offs
brought about by multiple objectives of management.
Rationale; The ability to make optimal decisions in natural resources management often eludes managers
because natural systems are characterized by uncertainty and complexity. Decisions are usually made with
a degree of risk-aversiveness at some unknown opportunity cost, or worse, decisions are made under
unreasonable or unverifiable assumptions about how the managed system operates. Controversies and
disputes regarding management often stem from fundamental uncertainties about key ecological processes.
The rationale for this research is that decision-making should directly confront uncertainty, with a focus on
its reduction over the long term.
Approach; Two vertebrate species on the Piedmont National Wildlife Refuge in central Georgia are of
interest in this research. The endangered red-cockaded woodpecker (Picoides borealis) is the target organism
of most silvicultural activities on the Refuge. The wood thrush (Hylocichla mustelind), a species which is
not targeted by management but is nevertheless of conservation interest, responds to this form of
management in ways that are mostly unknown. I will use principles of adaptive resource management and
adaptive optimization to find silvicultural decision policies that maximize persistence probability for the
woodpecker population while maintaining populations of wood thrush above some desired threshold.
Models describing the response of each population to habitat manipulations will form the basis for seeking
policies. I will express system uncertainty through the specification of several plausible candidate models
for each population and through the use of stochastic model components. I will derive near-optimal decision
policies using stochastic search procedures. An important state variable to be used in deriving policies is
the "information state" of the system. This state represents relative confidence in competing models of
biological processes, and it is determined by measuring agreement between model predictions and system
observations.
Status; Monitoring efforts for the two bird species continue at the Refuge. I completed a spreadsheet-based
computer demonstration of management under uncertainty and presented the demo to Refuge managers. I
am currently preparing a digital map of the Refuge to be used as input to spatial models of forest and
population dynamics. I have developed and analyzed a preliminary model of forest response to management
activities; population models are forthcoming. My work with the genetic algorithm continues, particularly
in tailoring it to perform adaptive dynamic optimization.
Papers & Publications; Moore, C.T., Conroy, M.J., and Boston, K. 2000. Forest management decisions
for wildlife objectives: system resolution and optimality. Computers and Electronics in Agriculture (in
press)
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U915364
VARIATIONS IN FOG AND CLOUD COMPOSITION WITH DROPLET SIZE
AND THEIR INFLUENCE ON AEROSOL PROCESSING
Katharine F. Moore
Colorado State University
Objectives/Hvpotheses; To experimentally characterize how fog/cloud formation affects local aerosol
properties. The resulting data set should provide information regarding how fog/cloud processing impacts
aerosol subject to the PM25 and PM10 standards, and be useful for model validation.
Rationale; Atmospheric chemistry models predict and experimental measurements indicate that cloudwater
chemistry varies by droplet size. This has significant implications for atmospheric aqueous-phase reactions.
One important aqueous-phase reaction relevant to the growth of aerosol mass is S(IV) to S(VI) oxidation,
which depends non-linearly on cloudwater composition. Oxidation rate calculations based upon average
cloud droplet chemistry measurements can be misleading as composition varies by droplet size. For
example, recent results from California's San Joaquin Valley suggest that actual oxidation rates exceed rates
calculated based upon average droplet composition by factors ranging from 1.5 to 9. Aerosol sulfate is often
a significant mass fraction of paniculate matter and increases in aerosol sulfate mass frequently occur in the
presence of fogs and clouds. Understanding the impacts of cloud-processing of aerosols on particle growth,
production, and removal requires improved observations.
Approach; A new active cloudwater collector (the CSU 5-Stage) has been developed to separate collected
droplets into more fractions (five), than previously possible (two or three). The CSU 5-Stage has been used
successfully in the field—yielding five chemically distinct droplet size fractions over sampling intervals as
short as one hour. Current understanding of cloud droplet variation mechanisms does not explain all
measured chemical concentrations. The CSU 5-Stage collector, operated as part of an integrated field
sampling campaign, provides finer resolution and an improved understanding of spatial variations in cloud
chemistry. Complementary physical and chemical measurements to fully characterize pre-and post-cloud
aerosol, the cloud itself, selected gas-phase species, and meteorological conditions are simultaneously made.
Radiation fogs are particularly useful for isolating cloud effects on aerosol and have been studied in the San
Joaquin Valley.
Status; The measurements described above were made during January 1999 (at Davis, California, in con-
junction with a National Science Foundation-sponsored field project), and during January 2000 (near
Corcoran, California, in conjunction with a State of California-sponsored field campaign). Unfortunately,
due to the lack of fog, the January 2000 measurements' usefulness to this project's goals may be minimal.
However, while the January 2000 measurements remain to be evaluated, potentially they may be relevant
to both generalizing the January 1999 results, and examining "what if* scenarios for that location. The
relationships between the gas-phase, aerosol and cloud chemistry from January 1999 continue to be
evaluated. Local meteorological conditions are being examined to determine the influence of transport and
other physical processes on the measured quantities. Other investigators' recent results suggest that kinetic
limitations may play a role in the rates of aqueous-phase S(IV) to S(VI) oxidation, which needs to be
considered in evaluating pre- and post-cloud aerosol sulfate distribution. Kinetic limitations may be
important for understanding other observed concentrations as well. Finally, an investigation has begun into
the differences between measured quantities of labile reduced nitrogen species between the aqueous and
solid-phases, their potential for interaction with selected organic species, particularly in the aqueous-phase,
and the implications for production/removal/fate of precursor and resulting species.
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Papers & Publications; Bower, K.N., Choularton, T.W., Gallagher, M.W., Beswick, K.M., Flynn, M.,
Allen, A.G., Davison, B.M., James, J.D., Robertson, L., Harrison, R.M., Hewitt, C.N., Cape, J.N., McFadyen,
G.G., Martinsson, B.G., Frank, G., Swietlicki, E., Zhou, J., Berg, O.H., Metes, B., Papaspiropoulous, G.,
Hansson, H-C., Kulmala, M., Aalto, P., Vakeva, M., Berner, A., Bizjak, M., Fuzzi, S., Laj, P., Facchini,
M-C., Orsi, G., Ricci, L., Nielsen, M., Allan, B.J., Coe, H., McFiggans, G., Plane, J.M.C., Collett, J.L., Jr.,
Moore, K.F., and Sherman, D.E. 2000. ACE-2 HILLCLOUD: an overview of the ACE-2 ground based
cloud experiment. Tellus (in press)
Moore, K., Straub, D., Sherman, D.E., and Collett, J.L., Jr. 1998. Development of a new five-stage active
cloud water collector for size-resolved droplet sampling. American Meteorological Society, Proceedings
of the Conference on Cloud Physics, August 17-21, 1998, Everett, WA.
Xu, G., Sherman, D.E., Andrews, E., Moore, K., Hoag, K., and Collett, J.L., Jr. 1999. The influence of
chemical heterogeneity among cloud drop populations on aerosol processing in winter clouds. Atmospheric
Research 51:119-140.
Xu, G., Sherman, D.E., Moore, K., Andrews, E., Straub, D., Rao, X., and Collett, J.L., Jr. 1998. Variations
in cloud chemistry with drop size and their effects on aerosol processing in winter clouds. Proceedings of
a specialty conference (13th Annual Symposium on the Measurement of Toxic and Related Air Pollutants)
co-sponsored by the Air & Waste Management Association and the U.S. EPA's National Exposure Research
Laboratory. September 1-3, 1998, Cary.NC.
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U915616
A REMOTE SENSING ASSESSMENT OF LAND USE AND LAND COVER CHANGES
WITHIN THE HEADWATERS REGION OF THE RIO CONCHOS WATERSHED,
CHIHUAHUA, MEXICO
Pedro Muela
University of Texas, El Paso
Objectives/Hypotheses; To assess the significant changes in land use and land cover that have occurred
within the headwaters region of the Rio Conchos watershed using satellite data, and to conduct a water
quality survey of the river. The information derived from this study will serve as a temporal benchmark to
which future changes in land use, land cover, and water quality conditions are compared and quantified.
Rationale; The Rio Conchos is an exotic river that originates in the Sierra Madre Occidental of Mexico and
flows across the Chihuahuan Desert to join the international Rio Grande (Rio Bravo as referred to in Mexico)
in the area of Ojinaga, Chihuahua - Presidio, Texas (just west of Big Bend National Park). The Rio Conchos
is one of Mexico's largest river systems and is the largest tributary to the Rio Grande. In northern Mexico
where more than half of the land is dominated by arid and semiarid climates, and similarly in the adjoining
United States, water, its quantity, quality and efficient control is extremely critical. The headwaters region
of the Rio Conchos watershed is undergoing stress due to improper logging practices, overgrazing,
intensification of human use and other land uses that are frequently environmentally abusive. It is essential
that we develop the strategy and the database of environmental baseline information for long-term
monitoring of an important and often neglected river system.
Approach; This study utilizes digital satellite-borne sensor data (Landsat Multispectral Scanner and
Thematic Mapper imagery) from several time periods to delineate how much woodland, agricultural land,
and grassland was lost to logging and general misuse in the headwaters region of the river basin. The time
periods of interest are 1980,1992, and 1997. The use of multispectral Landsat (land satellite) data permits
us to measure and analyze the continuous change in both vegetation coverage and land uses that have
occurred within the study area over an extended period of time. It is important to identify areas where rapid
changes are occurring and to assess how these changes are impacting not only the headwaters region of the
watershed, but the entire watershed. This research project also involves the analyses of in situ geochemical
data collected during a one-time water quality survey of the Rio Conchos. The survey was conducted in June
1997, and the water quality information should serve as baseline information for long-term environmental
monitoring. This research has implications on both sides of the United States - Mexico border.
Status; We have obtained all the remote sensing data required for the study, and I have pre-processed
(correct for radiometric and geometric distortions) approximately 60% of the data. After completing the
pre-processing, the next steps are to classify the data and extract the change detection information for
evaluation. The water quality survey has been conducted and over 107 water samples were collected and
analyzed. The evaluation of the water quality data continues.
Papers & Publications; None at this time.
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U915135
TEMPORAL LINKS BETWEEN CLIMATE AND HYDROLOGY: INSIGHTS FROM
CENTRAL TEXAS CAVE DEPOSITS AND GROUNDWATER
MaryLynn Musgrove
University of Texas, Austin
Objectives/Hypotheses; Temporal changes in groundwater chemistry, as recorded in carbonate cements
deposited from groundwater in caves (speleothems) over recent geologic time, may be used to understand
mechanisms and time scales of variations in groundwater chemistry and their relation to climatic and
hydrologic factors.
Rationale; Relatively little is known regarding how groundwater chemistry evolves through time (e.g.,
decades to millenia). This knowledge provides a framework for assessing the controls of factors such as
climatic variations on aquifer and karst development, long-term patterns of recharge, and changes in flow
regimes. An improved understanding of paleoclimatic fluctuations in continental settings over geologic time
has far-reaching contributions to many aspects of Earth and environmental science and our understanding
of global-scale processes, including processes important for water management and water quality.
Approach; The Edwards aquifer of central Texas is developed in karstified Cretaceous limestone and is the
most significant water resource for the region. Numerous studies have detailed the development of the
aquifer, fluid hydrodynamics, and groundwater and limestone geochemistry. In this study, the integration
of strontium and uranium-series isotope measurements in conjunction with other geochemicaland hydrologic
tracing tools (e.g., carbon and oxygen isotopes and trace elements) is being investigated toward providing
improved sensitivity for reconstructing environmental records, and unique insight into the links between
climate variability, hydrology, and water chemistry.
Status; Geochemical and isotopic variations in vadose cave dripwaters of the Edwards aquifer refle«
interaction with soils and host carbonate aquifer rocks along different geochemical evolution pathway,,.
These evolution processes appear to be consistent regionally as well as at specific localities as documented
by Sr isotope values and Mg/Ca ratios over a 3.5 year period. Changes in vadose flow routes as a function
of rainfall-recharge is a mechanism that can account for these results. Temporal shifts in groundwater flow
routes may occur over multiple timescales and have implication for both karst aquifer evolution processes
and the interpretation of geochemical records in speleothems, which precipitate from vadose groundwaters.
Results of speleothem growth rates and geochemical and isotopic variations, constrained by high-resolution
geochronology for the last 70,000 years, indicate that speleothems have application for reconstructing
regional climatic conditions. However, variability in individual speleothem samples indicates the necessity
of an approach that integrates data from multiple samples and multiple sites in order to distinguish a response
to regional variability versus local conditions. The results presented here are the summation of this research,
which will finish in the fall of 2000. Current efforts are focusing on writing of papers and publications.
Papers & Publications; Musgrove, M., Banner, J.L., and Mack, L.E. 1999. Temporal variations in cave
dripwater chemistry: implications for speleothems as recorders of long-term variations in groundwater
chemistry. Geological Society of America Abstracts with Programs 31:A90.
Montaez, I.P., Osleger, D.A., Banner, J.L., Mack, L.E., and Musgrove, M. 2000. Evolution of the Sr and
C isotopic composition of Cambrian Oceans. GSA Today (in press)
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Sturchio, N.C., Banner, J.L., Binz, C.M., Heraty, L.B., and Musgrove, M. 2000. Radium geochemistry of
fluids in carbonate aquifers, Midcontinent, USA. Applied Geochemistry (in press)
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U915324
RECEPTOR-BASED MODELING OF GROUNDWATER CONTAMINATION
Roseanna M. Neupauer
New Mexico Institute of Mining and Technology
Objectives/Hypotheses: The goal of this research is to develop a receptor-based modeling technique to
improve characterization of known sources of groundwater contamination and to identify previously
unknown sources.
Rationale: Environmental transport modeling is commonly used to estimate the concentration of a
contaminant as it moves away from its source. In these source-based models, the source location and release
history are known or assumed to be known, and the concentration downgradient of the source is estimated.
Often, when contamination is detected at a receptor (e.g., groundwater monitoring well), the location and
release history of the contamination source are unknown. For these problems, source-based modeling is
inefficient; however, receptor-based modeling can be used to efficiently obtain information about the
contamination source. Receptor-based modeling uses the present position of the contamination as a starting
point, and models transport in reversed time to obtain information about the past positions of the
contamination. The result is a probability distribution for the prior location of the contamination (location
probability) or for the amount of time needed for the contamination to travel from an upgradient location to
the receptor (travel time probability). These probability distributions can be used to identify the most likely
sources of contamination. If contamination is detected at multiple receptor locations or at multiple times
at one or more receptors, the combined information reduces the variance of the probability distributions and
provides better information about the source location.
Approach; The governing equation for source-based models of contaminant transport in groundwater is
the advection-dispersion equation (ADE), with the contaminant concentration as the state variable.
Receptor-based models are governed by the adjoint of the ADE, with location or travel time probability as
the state variable. The adjoint equation models the same processes as the ADE, but the flow of information
is reversed in space and time. The governing equation and boundary and initial conditions of the
receptor-based model can be developed from adjoint theory. If contamination is detected at one receptor,
the solution to this adjoint equation describes the location or travel time probability distribution. For simple
geometries, the adjoint equation can be solved analytically; otherwise, it must be solved numerically. Any
numerical code that solves the forward ADE can also be used to solve the adjoint equation, although the state
variable and sources terms have different interpretations. If contamination is detected at multiple receptors
(multiple locations or multiple times at one or more locations), the resulting probability distributions are
functions of the single-receptor distributions for each detection and the probability of the spatial and tem-
poral separation of the detected contamination.
Status; The formal approach for obtaining the governing adjoint equation and its boundary and initial
conditions has been developed for conservative and reactive chemicals. The receptor-based modeling
technique has been developed for a single detection and for multiple detections, although additional
validation is necessary. We have illustrated the method for applying receptor-based modeling to standard
finite difference and finite element numerical models of contamination transport.
Papers & Publications; Neupauer, R.M. and Wilson, J.L. 1999. Adjoint method for obtaining backward-
in-time Jocation and travel time probabilities of a conservative groundwater contaminant. Water Resour Res
35(11):3389-3398.
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Neupauer, R.M. and Wilson, J.L. Adjoint-derived location and travel time probabilities for a multi-
dimensional groundwater system. Water Resour Res (submitted)
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U915185
ENVIRONMENT AS SOCIAL CONTEXT: A STUDY OF PERSISTENT PLACES
IN THE ARCHAEOLOGY OF THE FLAGSTAFF REGION, ARIZONA
Joanne M. Newcomb
The University of Arizona
Ob j ectives/Hvpotheses; Recently, in archaeological studies of the environment, a landscape approach has
emerged as an alternative to functional ecological studies. The utility of the landscape concept lies in its
ability to unite both the physical, social, and temporal aspects of human-environmental interaction.
Although other researchers in the Southwest have looked at human-environmental interaction, the
combination of landscape theory plus high-quality archaeological and environmental data from the Flagstaff
area of northern Arizona, coupled with CIS technology, provides a new way of testing previous theories of
land-use. The study of landscape is a synthetic process that integrates ecological, geological, and cultural
data in order to understand the changing social and political organization of communities through time.
Persistent places (areas of long-term land use) provide a temporal continuity in the landscape that is useful
for modeling changes in prehistoric landscape and society. A model of long-term land use spanning 600
years of Flagstaff prehistory will be constructed to examine four major research questions: 1) What are
persistent places and how are they characterized? 2) How are communities connected to these areas? 3) What
is the importance of persistent places to community survival? 4) Does changing use of persistent places
mirror social organizational changes in communities?
Rationale; Though many researchers promote the usefulness of landscape theory to archaeological studies,
few have actually tried to operationalize it. If landscape theory is ever to be broadly useful to archaeologists
as a means for understanding the social context of environmental phenomena, then concrete examples of its
use in archaeological settings with archaeological data must be shown.
Approach; This project combines CIS technology and analyses with underutilized data on small scatters,
site data, environmental, and climatic data, providing an example of how a landscape approach in
archaeology can be operationalized. Persistent places and their range of variation will be identified by
combining traditional cluster analyses of material remains through time with GIS analyses of site and artifact
data. To construct a model of long-term land use, information about persistent places will be combined with
data from ethnographic, archival, and field sources. In addition, the impact of environmental events on
land-use strategies will be examined by mapping droughts, floods, killing frosts, and the volcanic eruption
of Sunset Crater onto an environmental baseline of temperature and precipitation derived from tree-ring data.
Status; Data collection is underway and preliminary analyses will be completed this summer.
Papers & Publications; None at this time.
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U915576
NESTING SUCCESS OF A HAWAIIAN HONEYCREEPER ALONG AN ALTITUDINAL
GRADIENT OF CULICINE MOSQUITOES
Bonnie M. Nielsen
University of Idaho
Objectives/Hypotheses: Range reductions, extinctions, and population declines have been documented
of Hawaiian honeycreepers (Passeriformes: Fringillidae: Drepanidinae) inhabiting low-elevation forests.
Particularly interesting in considering the altitudinal trend of these declines is the opposite trend in
abundance of the introduced night-biting mosquito (Culex quinquefasciatus), the primary vector of avian
malaria (Plasmodium relictum). I proposed the hypothesis that reduced nesting success from greater
exposure to avian-malaria vectors is a factor in reduced low-elevation Hawaiian honeycreeper populations.
I addressed this hypothesis by testing the predictions that Apapane nesting success has a negative
relationship with C. quinquefasciatus abundance and infection status and a positive relationship with
elevation. My specific objectives were to: 1) document nesting success of Apapane along the altitudinal
gradient of C. quiquefasciatus mosquitoes, and 2) determine relationships between Apapane nesting success,
elevation, and prevalence and infection status of C. quinquefasciatus within the nest vicinity.
Rationale; No reports of nesting success of a Hawaiian honeycreeper or other Hawaiian bird along the
altitudinal gradient of C. quinquefasciatus mosquitoes are available. This work provides valuable new
information on relationships between introduced disease vectors and nesting success of an endemic Ha-
waiian honeycreeper as well as on the importance of nesting success as a limiting factor of low-elevation
populations.
Approach; I monitored nesting success of 87 Apapane (Himatione sanguinea) nests and abundance of Cu-
lex quinquefasciatus mosquitoes along an altitudinal gradient spanning 610-1,829 (2,000-6,000 ft) on the
Kona Unit of the Hakalau Forest National Wildlife Refuge, Hawaii Island, 1998-1999. I measured
abundance of C. quinquefasciatus mosquitoes caught below each nest over 7 trap nights starting within 1
week of nest termination. Avian malaria (Plasmodium relictum) infection status was quantified by
examination of mosquito midguts for developing oocysts. Elevation was recorded at each nest.
Status; Data collection and analyses are complete.
Papers & Publications; None at this time.
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U915413
TORRES STRAIT MARINE FORAGING AND MARINE RESOURCE UTILIZATION
Karma C. Norman
University of Washington
Objectives/Hypotheses; To gather and analyze data on western Torres Strait Islander marine resource use,
and thereby evaluate two competing models of human utilization of natural resources. An optimal foraging
model of human resource use predicts that defendable territories of limited access are likely to produce
conservation-oriented behaviors, such as forgoing the harvest of smaller, immature marine animals. An
alternative view of small-scale human societies holds that they are often, in a broad sense, socially invested
in conserving future stocks. I plan to test these alternative hypotheses, as well as others regarding marine
resource management. The data and subsequent evaluations will contribute to an enhanced understanding
of the micro-ecology of fishing, such that localized and cooperative management institutions have a stronger
basis for effective management of coastal resources.
Rationale; Australia appears to be on the brink of a more centralized approach to coastal resource
management. However, due to recent political and legal outcomes, any national coastal policy will have to
involve discussions of indigenous Torres Strait Islander management of the Strait's marine resources. An
examination of the current Islander structure of marine resource management is, therefore, timely and
important, and of relevance to similar environmental management situations in North America. Moreover,
the region is home to unique marine ecosystems as well as numerous endangered and threatened species.
This is particularly true of Badu, Mabuiag, and Moa Islands in the western Torres Strait, where threatened
species like dugong (Dugong dugon) and green sea turtles (Chehnia mydas) are subject to subsistence
harvest. In the critical environmental setting of the Torres Strait, a greater understanding of the micro-
ecology of fishing is of particular importance, and the western island of Badu has provided an apt location
for a field research base. Finally, the findings of this study should provide a valuable case study, and thereby
contribute to environmental management in other areas of the world.
Approach: This study makes use of extensive participant observation such that quantitative and qualitative
data on Islander marine foraging behaviors can be obtained. In particular, quantitative data on the size of
resources harvested, including shellfish and reef fish, will be compared in relation to the locations in which
the resources were acquired. Of significant comparative value are any potential size differences that may
occur in foraging patches subject to differing access regimes. Torres Strait waters feature regions of open
access, where the law of capture may apply, as well as clan and community-based fishing and foraging
territories. The primary research method employed will be one of focal follow, wherein individual harvest
outings are observed from beginning to end. During the focal follow process, I intend to record catch data
that will include sizes, locations and distributions. Field research will be supplemented by examination of
published work on similar case studies, including those in other areas of the Pacific.
Status; Research funding commenced in September 1998, and an initial field visit was completed during
September, October, and November of 1999. Preliminary data were primarily qualitative in nature, and the
Torres Strait Regional Authority (TSRA) as well as the Badu Island community itself has approved further
and more intensive quantitative research. The TSRA and Badu Island Council will engage this project in
mapping of marine territories as well as documentation of marine tenure systems. This project should be
completed in June 2001.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915366
TRANSPORT AND RETENTION OF BAY ANCHOVY
AND WHITE PERCH IN CHESAPEAKE BAY
Elizabeth W. North
University of Maryland
Objectives/Hypotheses: Evaluate potential impacts of physical conditions on early life histories of two
estuarine fish, bay anchovy (Anchoa mitchilli) and white perch (Morone americana) in Chesapeake Bay.
This research will describe mechanisms of dispersal or retention of eggs and larvae that result from
small-scale interactions of physics and biology and explore their implications for recruitment (survival to
adulthood).
Rationale; Since the net flow of water is out of an estuary, fish that utilize estuaries as spawning and
nursery areas must have mechanisms to retain or disperse larvae within them. Dispersal and retention
mechanisms are influenced by the interaction of physics (salinity, temperature, winds, tides, freshwater flow,
circulation patterns) and biology (prey abundance, predator avoidance, larval development). These
interactions can be important for larval survival and could significantly influence fish recruitment.
Approach; Factors that control the transport and retention of white perch and bay anchovy larvae were
studied in two projects on Chesapeake Bay. Data on bay anchovy eggs and larvae were collected on a 10-day
cruise in June 1996 in the mainstem of the Bay. After a survey of larval abundance along the Bay axis,
repeated depth-stratified sampling was conducted at a fixed station. Depth-stratified collections of
ichthyoplankton, microzooplankton, and gelatinous zooplankton were made as well as water column
measurements of physical parameters. Multivariate statistics are being used to identify the biological (prey,
predators, ontogeny) and physical (tides, dissolved oxygen, temperature, salinity) factors that most influence
bay anchovy egg and larval distributions.
The estuarine turbidity maximum (ETM), an important physical feature located near the landward margin
of the salt front in upper Chesapeake Bay, is hypothesized to act as a retention zone for white perch larvae.
To evaluate this hypothesis, data were collected in three cruises during May 1998 and two during May 1999.
On each cruise, the ETM was located with a series of CTD casts along the Bay's axis. Gradients in
depth-specific abundance of ichthyoplankton, zooplankton prey offish larvae and potential predators were
mapped above, within, and below the ETM in conjunction with physical measurements. In addition, a time
seriesof depth-stratifiedichthyoplankton and microzooplankton collections and physical measurementswere
conducted within the ETM. Physical and biological characteristics of the ETM that are important for larval
survival are being identified and larval retention mechanisms will be determined. Results of the field
sampling program are being evaluated and analyzed with respect to young-of-the-year indices, historical
data, and numerical modeling of larval behavior to link physical and biological conditions to larval survival
and juvenile recruitment.
Status; All field studies and research cruises are completed. Multivariate statistical analyses for the bay
anchovy component and laboratory analyses for the white perch component are nearing completion.
Numerical modeling and statistical analysis for the white perch component will begin in fall 2000.
Dissertation will be complete in 2001.
Papers & Publications; North, E.W. and Houde, E.D. 1999. The influence of physical conditions on
dispersal and retention of bay anchovy and white perch eggs and larvae in Chesapeake Bay. Poster.
http://www.hpl.umces.edu/services/IESnew/STARposterl2.pdf
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STAR Graduate Fellowship Conference
North, E.W. and Houde, E.D. 2000. Potential impact of Site 104 dredging and sediment placement
operations on fish eggs and larvae in the upper Chesapeake Bay. Report to Maryland Environmental Service.
North, E.W. and Houde, E.D. Retention of white perch and striped bass larvae: biological-physical
interactions in Chesapeake Bay estuarine turbidity maximum, (in preparation)
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STAR Graduate Fellowship Conference
U915197
ESCAPING THE GROWTH MANAGEMENT CONUNDRUM: LOCAL COMMITMENT
TO LAND USE PLAN IMPLEMENTATION IN COASTAL NORTH CAROLINA
Richard K. Norton
University of North Carolina, Chapel Hill
Objectives/Hypotheses: This research addresses the question of how local commitment to both the process
and goals of land use planning, relative to local economic and demographic factors, affects the on-the-ground
implementation of land use plans. More broadly, the research addresses the role played by land use planning
in a comprehensive state-local growth management program.
Rationale; Growth management ideally calls for thinking ahead and guiding the development of the built
environment before it is too late to be effective. Moreover, good common and environmental sense suggests
that it is much more effective and efficient in the long run to identify and conserve a region's most valuable
natural resources in the first place rather than trying to restore those resources once they have been degraded.
Yet, practical experience suggests that communities often fail to recognize the value of growth management
until development is extensive, ongoing development pressure is high, and environmental resources have
already begun to suffer—that is, until after the prime time to manage growth has passed. This creates a
conundrum: In order to be truly effective, communities need to set the stage to manage growth before
development is out of control, yet they seem to need a high degree of development pressure before they can
muster the political will to do so. What can states do to encourage regions and communities within their
borders to prepare good growth management plans and to implement them while there is still time to be
effective? This question is an especially timely one for the State of North Carolina as it struggles to handle
tremendous levels of urban and suburban growth across the state and as it considers adopting a state-wide
"smart growth" program. Implicit within this larger question are a series of more fundamental questions,
such as: What role should government play in guiding private land development? How should res-
ponsibilities and prerogatives be divided between state and local government? What approaches—such as
direct regulation, incentives, and land use planning—might state and local governments employ to manage
growth effectively? Where and how should government strike the balance between local economic
development and environmental protection and who should decide?
Approach; The dissertation uses the North Carolina Coastal Area Management Act (CAMA) land use
planning program for context and draws its theoretical foundations from the planning and public
administration literatures in the areas of growth managementand sustainable development, land use planning
and plan implementation, and intergovernmental relations. The research design employs a three-phased
approach to data collection and analysis that integrates both qualitative and quantitative assessment. The
unit of analysis is the locality, including all 20 CAMA counties and 40 communities that have prepared
CAMA land use plans.
Status: I am actively collecting data and am on schedule to defend my dissertation in early spring 2001.
Papers & Publications; None at this time.
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U915426
SAHELIAN ELEPHANT RESEARCH AND CONSERVATION PROJECT
Anne M. Orlando
University of California, Davis
Objectives/Hypotheses; To facilitate long-term conservation of the elephants of the African Sahel
(Loxodonta africand) by building a knowledge base of patterns and determinants of habitat use, survival
strategies, environmental constraints, and resource needs.
Rationale: The once extensive populations of elephants in West Africa face near total extinction due to
poaching for the ivory trade and habitat destruction. Little is known about the behavior, genetics, social
organization, population dynamics, and ecology of West African elephants. Only one elephant population
remains in the African Sahel, practicing the longest migration and occupying the largest home range of any
known elephant population. The 300-400 Gourma elephants have shared the near-desert terrain with
nomadic and transhumant pastoralists and their goats, sheep, cattle, donkeys, and camels for centuries. Yet,
recent years of drought, famine, political/economic changes, and aid endeavors are creating conflicts
between elephants and humans. Recent advances in range ecology theory contend that mobile, opportunistic
land use regimes, like those traditionally practiced by people in the Sahel, are optimal in the arid and
unpredictable ecosystems of dryland Africa. Thus, flexible frameworks for integrated land use may be
necessary to support both wildlife and human populations in the vast expanses of dryland Africa.
Approach; I am using a multi-scaled approach to identify and characterize the environmental influences
on elephant habitat use at the landscape, population, and individual levels. Five bull and five cow elephants
have been fitted with Global Positioning System (GPS) tracking collars, which record and store elephant
locations every 2 hours, continuously, and are downloaded aerially every 8 weeks. These data are inputted
to an integrated ArcView GIS database based on LANDS AT 7 satellite images of the study region, which
contains information on water points, vegetation, salt and mineral deposits, topography, soils, human
settlements, and migration routes. Elephant habitat use and ranging patterns, sub-group distributional
patterns, and other data will be analyzed for a period of 2 years using collar data, aerial observations from
ultralight aircraft, and ground observations. Landscape-level analysis is complemented by ground-based
observation to understand differential resource use, individual-specific environmental needs and constraints,
and decision-making by elephants. Collared elephants and their associated groups are followed for
behavioral observations in day and night hours during each of four annual seasons. Activity budgets, species
and parts of vegetation eaten by calves, juveniles, adult bulls, and lactating and non-lactating cow elephants
are recorded. Elephants are individually identified and measured with a photo-imaging system to estimate
population demographic parameters. Elephant ecologicaland decision-makingstrategiesare being compared
with those of sympatric mobile human societies using an energy-based decision-making model, to provide
starting points for integrated land use planning. I am working closely with local inhabitants, government
officials and development agents to produce utile research products and effective conservation structures.
Status; A preliminary feasibility study was conducted during June-September 1998 and collaboration was
forged with relevant international development and conservation agencies. I returned to Mali in January
2000 and have deployed 10 GPS collars on elephants, and begun daily observations of elephant behavior,
grouping patterns, foraging, and individual identification. A complete census of the population was
conducted in May 2000. An extensive GIS database is being integrated from satellite images and other
research sources. This study will proceed through January 2002.
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Papers & Publications: Orlando, A. Status report for the Sahelian elephants of Mali and Burkina Faso.
(submitted to the Convention on International Trade in Endangered Fauna and Flora (CITES), Nairobi, April
2000)
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STAR Graduate Fellowship Conference
U915376
ANALYSIS OF FLUORESCENCE RESPONSES OF PAH MIXTURES
Todd E. Pagano
Tufts University
Objectives/Hypotheses; To improve the understanding and characterization of subsurface polycyclic
aromatic hydrocarbon (PAH) mixtures, including fuel contamination, detected by our laser-induced
fluorescence (LIF) with fiber optic and cone penetrometer technology (CPT) sensor.
Rationale: The high sensitivity of fluorescence spectroscopy has made the technique popular among
scientists for many applications. In situ monitoring of subsurface environments using LIF-CPT is one such
application with great potential. Despite the advantages of fluorescence spectroscopy, two phenomena, the
inner filter effect and resonance energy transfer, can prevent the reliable interpretation of obtained data when
the concentrations of fluorophores and chromophores are high. The integrity of most currently used data
analysis algorithms requires that a fluorophore present in the sample display the same spectral signature,
apart from a single concentration-dependent scaling factor, regardless of its concentration or the con-
centrations of other components of the sample. However, it is observed that a given compound, or a typical
mixture such as a fuel, shows different spectral fingerprints at different concentrations in nonpolar solvents
such as cyclohexane. Therefore, it is imperative to investigate and characterize these phenomena that hinder
qualitative and quantitative analysis of acquired data.
Approach; The dual-pathlength method, a novel experimental technique developed by our group, quantifies
separately the extent of spectral distortion by primary and secondary inner filtering and corrects for both
inner filter effects. The method avoids reliance on separate absorption measurements that add error by
introducing a second instrument with different instrumental parameters/specifications, while also avoiding
the need for difficult absorption measurements of extremely optically dense samples (especially fuels). In
addition to the dual-pathlength method, a standard procedure for inner filter effect correction will be used
for comparison. Three-dimensional fluorescence excitation emission matrices (EEMs) of various con-
centrations of PAH samples will be compensated for inner filtering by the two techniques. The adjusted
spectra will then be subjected to data analysis algorithms, such as factor analysis and neural network
schemes, for proper identification and quantification of individual components within mixtures.
Status; We have studied the fluorescence responses of simple single-component PAH solutions and
complex fuels in a standard spectrofluorometer. The behavior of inner filter effects in the single-component
system is pretty well understood. However, elucidating the exact mechanism within the fuels is still a work
in progress. Laboratory simulated (mock fuels) will be utilized as a more simplistic version of the real-world
fuel. A strategic four-component PAH mixture will be investigated as a model for the "wide-cut" fuels to
help us better understand the photophysical effects taking place in the complex systems. The evaluation of
resonance energy transfer must still be examined before the information can be used to fully characterize
PAH systems. Also, measurements equivalent to those made in the laboratory would have to be added to
the LIF-CPT probe to permit correction of the in situ data for the inner filter effect.
Papers & Publications; Pagano, T.E. and Kenny, J.E. 1999. Assessment of inner filter effects in fluo-
rescence spectroscopy using the dual-pathlength method—a study of the jet fuel JP-4. Proc SPIE
3856:289-297.
Pagano, T.E., Waltrous, K.O., and Kenny, J.E. 2000. A practical technique for the deoxygenation of
solutions, (in preparation)
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STAR Graduate Fellowship Conference
U915S66
CHARACTERIZATION AND UTILIZATION OF INSTRUMENTS FOR REAL TIME SINGLE
PARTICLE ANALYSIS IN LABORATORY AND FIELD MEASUREMENTS
Syliva H. Pastor
University of California, Riverside
Objectives/Hypotheses; To perform chemical analysis of ambient paniculate matter on a single particle
basis The mam foci of the research project include the characterization and optimization of the single
particle technique and its use for the analysis of ambient aerosols sampled in field studies and particles
generated by reactions in a laboratory reaction chamber
Ratmnale: Ambient particles affect the environment and human health, yet they are poorly understood. The
results will provide transmission efficiency curves for the aerosol time-of-flight mass spectrometry
instruments, allowing for the understanding of and correction for instrument biases. The size and chemical
composition of particles will be determined in the controlled environment of the laboratory and field.
Furthermore, instrument comparisons and calibrations will be performed from the field study data.
ApProach: ,The technitlue known as aer°s°l time-of-flight mass spectrometry technique is being used to
analyze single particles in real time. The aerodynamic size of each particle and its positive and negative ion
TTS^h f Td< ?„' ^^ ^ °f ^ investiSation is to Characterize and optimize the instrument.
^iTSS T , "'It t0 * SC3led !n °rder Sh°W 3 rePrese«'atwe size distribution of the
sample. There are several adjustable parameters that will be examined to optimize the systems Next, the
0^^^
Iduc ed and I ySIS t P,T, / 'Y *"** of Iocations' Several field studies have already been
^SstTiTJh"8* "^ u far filtUre" An0ther part of m* instigation is the study of
pmici"ate matter concentratton *» ^ -^ •
"- "d.ftlB!T- K'A- lm' Tin.e-of-fligh.masssp.c.rom^ma.hods
aerosol pamdes. TRAC-Trends in Analytical Chemisby 17:346-356.
Gross, D.S., Oalli, M.E., Silva, P J Wood v j » , • i
^-
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U915618
AN ENHANCED AEROSOL SIZE DISTRIBUTION METHODOLOGY
Roderick R. Pearson
University of Texas, El Paso
Objectives/Hypotheses; The goal of this project is develop an alternative means to analyze atmospheric
tropospheric aerosol physical properties from radiance measurements. An additional goal is to create a
template for monitoring atmospheric aerosol distributions for local and regional entities complying with the
U.S. Environmental Protection Agency's regulations on air quality.
Rationale: Recently, interest has increased in the effect of Aerosol Radiative Forcing on global climate
change. This is a consequence of better understanding of the production of anthropogenic troposphere
aerosols. These aerosols are suspected to have doubled the amount of solar radiation scattered back into
space and thus play an indirect role in climate change. A second effect that has received more interest as
of late is the effect of aerosols, natural and anthropogenic, on human health. Also, the regular inhalation of
aerosols is suspected to be a key factor in upper respiratory ailments in children and the elderly. Ground
based monitoring systems are in place. A major question about ground based monitoring « whether or not
the particles undergo chemical changes when collected on filters. If there are reactions on the filters, errors
are present upon analysis of the filter. This implies that the best time to analyze the aerosols is when they
are suspended in the atmosphere. Both reflection of solar radiation and inhalation occur when the particles
are suspended in the atmosphere.
; The initial phase of the project will be the analysis of existing models
This will allow for the documenting of strengths and weaknesses of each model.
documentation phase, the possibility of developing a new and more accurate, first- pn nciplc s model for
electromagnetic scattering from a single aerosol particle will be explored. This ^del would sub timte fo
the corresponding algorithms in the existing radiative transfer code, From
improveanddevelopthepropermethodology^^
remote sensing data, e.g." MISR and ground based radiometers. ^^
statistical comparison with several data sources. One source will be the
approximation models. A secondary source will be modeled dispersion data
monitoring station data to give an overall particle size distribution ^
dispersion data will be derived from a prognostic meteorological model, tf» Penn State/NCAR |Mesosca«e
Modeling System (MM5). MM5 will be used to develop wind profiles in the analysis of aerosol dispersion
in the local airshed.
Ste: The T-Matrix, and MIE codes have been tested and documented. M™"^"^"^
^developed theory for electromagnetic scattering ftom a angle irregu arty shaped aeroso particle
compares well with standard methods such as MIE and the Dipole approbation. MM5 analysis is com
PtaeTd tajX K ta b«n done. Tnat data is being correlated with ground monitoring sta.,0,,
data to produce a particle size distribution profile.
Papers & Publications: Manuscripts submitted for review.
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STAR Graduate Fellowship Conference
U915398
METAL SPECIATION AND SEQUESTRATION IN WETLAND SYSTEMS
Edward Peltier
Northwestern University
Objectives/Hypotheses: To determine the suitability of wetland systems for remediating metal con-
taminated sites. This includes answering two related questions: 1) How do metals partition and speciate in
wetland systems? 2) Can metal sequestration in the sediment phase be regarded as irreversible?
Rationale: The use of natural or created wetlands as treatment systems for a wide range of contaminants
has gained acceptance in recent years. Wetlands have been shown to be a versatile treatment option, able to
deal with a wide range of contaminants, both organic and inorganic, including trace metals. This versatility
could potentially be applied to the remediation of brownfleld and former waste disposal sites, which often
contain a mix of organic and inorganic contaminants. In many cases, wetlands could provide a low cost and
low intensity treatment method that could alleviate the danger of contaminant release from the site through
degradation of organic compounds and immobilization of trace metals in the sediments. However, concerns
remain about the potential for bioaccumulation of trace metals in the flora and fauna of the system,
particularly birds and wildlife. It has been proposed that the presence of sulfur and anoxic sediments will
results in sequestration of trace metals into metal sulfide compounds whose low solubility will make these
contaminants essentially bio-unavailable, reducing the overall ecological hazard of the site. In order to
verify this hypothesis, it is necessary to gain a better picture of the speciation of metal compounds in a
wetland system and to determine their potential for remobilization.
Approach; Sampling experiments will be carried out in impacted wetland sites in the Calumet Region of
Southeast Chicago. This sampling will determine the major speciation of trace metals and assess their
bioavailability in order to establish the validity of the above hypothesis. An important feature of this
research is to further the use of non-destructive analytical methods that allow the determination of oxidation
states, mineral phases, and contaminant associations of metal contaminants in natural samples without
chemical extraction. Sampling will include the use of three state-of-the-art techniques to look at participate
associated contaminants and metal complexity in the aqueous phase: Analytical Electron Microscopy
(TEM-EDS), X-ray Absorption Fine Structure (XANES and EXAFS), and Voltammetry.
Kinetic experiments will be conducted to determine the long-term stability of trace metal sulfide phases.
Dissolution kinetics for the oxidation of ZnS, a representative trace metal sulfide will first be determined
in the pure phase as a function of pH, oxidizing agent, and aqueous phase makeup. Once this baseline data
is established, the effects of mixed solid phases (particularly mixed iron-zinc sulfides) and aqueous phase
metal complexmg ligands on zinc dissolution will be determined.
Status: Field sampling in the fall of 1999 has shown that, as expected, the primary association of sediment
zinc is with sulfide phases. Rooted plants showed little bioaccumulation of Zrv or Pb, while aquatic plants
displayed greater accumulation of both trace metals. Aqueous phase concentrations of Zn, Pb, and Fe were
low. Further sampling is scheduled for spring 2000 to confirm these results and to measure trace metal
accumulation by benthic organisms. A batch-recycle reactor has been developed to determine the kinetics
of ZnS oxidation and .s now operational. Current studies are determining kinetic rates for the oxidation of
pure phase ZnS m oxygenated water over a varying pH range.
^^^M: Peltier, E. and: Gaillard, J.F. 1999. Metal sequestration in wetland systems:
exploration of metal sulfide chemistry and kinetics. Poster for MEC Workshop, Houghton, MI.
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STAR Graduate Fellowship Conference
U915560
COLLOIDAL STABILITY IN AQUATIC SYSTEMS: THE ROLES OF CALCIUM
AND NATURAL ORGANIC MATTER
Adrian C. Penisson
The Johns Hopkins University
Objectives/Hypotheses; Colloids are ubiquitous in natural and technological aquatic systems and can
significantly affect environmental quality in these systems. Most aquatic colloids are at least partially coated
with natural organic matter (NOM). The goal of this research is to provide the first comprehensive study
of the effects of divalent cations (calcium, in particular) on the adsorption of NOM by aquatic colloids and
the resulting effects on colloidal stability. The specific objective is to test the hypot hesis'^t d.yalen
cations affect colloidal stability through specific interactions with colloids and their adsorbed NOM layers
that alter the amount and conformation of adsorbed NOM and the electrostatic properties of the colloids and
NOM.
Rationale: Colloidal particles can affect the transport and transformation of environmental points or
be pollutants themselves. Because colloids can affect both the aesthetics (turbidity) and safety (pathogens,
microorganisms) of drinking water, the removal of colloidal particles is an essential function of many water
treatment processes. Although calcium is a major constituent of many natu^
the effects of solution chemistry (PH, ionic strength, NOM) on colloidal stability (the tendency of oUoida
particles to aggregate or deposit) have focused primarily on systems contaming only ™»°™^** on
(e.g., Na+). Those studies, which have addressed divalent cations, indicate that they may affec collo.da
Phetmenainfundamentallyd^
ofcateiumandNOMoncollo,™^^
of pollutants in natural aquatic environments and the development of improved water treatment processes.
Approach: This study will bethe firstto integrate measurements ofNOM ^^^
laPeTlhlcIness, electrophoretic mobility, and coagulation kinetics (collo.da. stability) "Jhe Presene of
calcium for positively- and negatively-charged metal oxide colloids. Because ^
natural aquatic colloids and NOM, an approach involving model systems » ^»«*- f^
rfmodelp^^
the relative importance of hydrophobic effects, macromolecula, -effects > electrostat,^
chemical interactions among calcium, oxide surfaces, and NOM to be > obtained. ™
will be used to determine the charge of the model particles and mode ,1 NOM
strength, and calcium concentration. NOM adsorption
, .
divalent cations.
elNOM^
completed by 2002.
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STAR Graduate Fellowship Conference
Papers & Publications: None at this time.
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U915628
THE LONG-TERM EVOLUTION OF COMMUNITY STRUCTURE AMONG
BENTHIC MARINE INVERTEBRATES
Shanan E. Peters
The University of Chicago
Q^ectives/Hvpotheses: To: 1) document the long-term evolution of community structure during.to
oTdovician radiation of benthic marine invertebrates, 2) explore the relationship between morPh^
disparityandcommunity^^
of abundance/rarity, and 4) determine environmental factors important in maintaining withm-habitat
biodiversity among benthic marine invertebrates.
Ration^: Biodiversity is an historical product. Efforts to evaluate the current
pTel^he outcomes of environmental change may greatly benefit from a ^
of biodiversity and the factors that influence it over the long term. Paleo
opportunity to examine changes in global, regional, and local biodiversity' acros « ™^
I am examining the long-term evolution of community structure framed within the larger contexts
Phanerozoic diversity patterns and environmental change.
condition. Further changes i
or when new taxa immigrate.
iog^.y ba,ed Pdic,io«s
from North America. The Ordovician is par!fcoJarty taxonomic diversification ano morpn.^,,
evolution of community structure because it is a P6"0^^p.j°^measured using an appropriate summary
evolution for many modern and extinct groups, venne ^ analyses and from simple independent
'ommuqZlvel pdeontological database containing species-level
„ TrSc data as well as information about paleoenvironmental
toTdTess many hypotheses concerning the evolution of community
wjuumons, 11 siiuuiu uv j/w-^"'-- iij *• ft »•„_
structure and the influence of abundance on rates of evolution.
evolution of community structure.
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STAR Graduate Fellowship Conference
Papers & Publications; Peters, S.E. and Bork, K.B. 1999. Species-abundance models: an ecological
approach to inferring paleoenvironment and resolving paleoecological change in the Waldron Shale
(Silurian). PALAIOS 14:234-245.
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STAR Graduate Fellowship Conference
U915419
ENVIRONMENTAL SALINITY AND STINGRAY GILLS: FROM BIOCHEMISTRY
TO CONSERVATION BIOLOGY
Peter M. Piermarini
University of Florida
Objectives/Hypotheses: Develop a physiological index to help determine whether a given freshwater
elasmobranch species is stenohaline (salinity restricted) or euryhaline (not salinity restricted) without
conducting long-term acclimation experiments. Determine what physiological factors restrict or allow
freshwater elasmobranchs to inhabit environments of varying salinity.
Rationale: Various freshwater elasmobranch (sharks, skates, and rays) species are threatened by human
induced pressures, such as over-fishing and pollution. In general, these fish are known to be very susceptible
to environmental disturbances, since they have a relatively low fecundity, long time until sexual maturation,
and long gestationai periods, compared to other fishes. In fresh water, elasmobranchs are faced with an
additional constraint of physical space, which may enhance the detrimental effects of fishing and pollution.
Unfortunately, little is known about the general biology of these animals, so basic facts about their life
history are unknown, i.e., are they physiologically restricted to their freshwater environment? If a given
freshwater species is restricted to a certain environment, it would be under a greater threat of extinction than
a species that can readily move out of that habitat. Therefore, knowledge of a species' salinity tolerance
would be useful for prioritizing which species are managed or conserved.
Two freshwater elasmobranch species will be used as models for this study: 1) the euryhaline
(non-restricted) freshwater Atlantic stingray (Dasyatis sabind), and 2) the stenohaline (restricted) freshwater
Amazon River stingray (Potamotrygon laticeps). Biochemical and morphological changes in the gill
epithelium of teleost fishes are known to be critical for successful adaptation to varying environmental
salinities. For example, certain changes in the expression of key ion regulatory enzymes (i.e., Na,K-ATPase)
and ultrastructure of ion regulating chloride cells, are characteristic of seawater vs. freshwater life. In
addition, these characteristics are often dependent on the salinity tolerance of the species. Similar features
can be probed for in the gills of the above study species using the techniques of Western blotting,
immunocytochemistry, and electron microscopy. By comparing these parameters betwee n the two study
species, it can be determined what features are characteristic of euryhalme and stenohaline freshwater
species, respectively.
Once the characteristics of euryhalinity vs. stenohalinity are established, the threatened species can be
investigated By matching up their characteristics with the model species, a salinity tolerance could be
predicted. In conjunction with other biological data, this would aid in determining which species are m a
more immediate need of conservation and management plans. Another benefit, especially for ^threatened
species, is that the techniques require relatively small amounts of tissue, which could be collected without
sacrificing large numbers of animals.
Status: Expression of Na,K-ATPase and morphological characteristics associated with the gills of the
euryhaline freshwater species (D. sabind) have been established. Currently I am collecting .data on the
stenohaline species (P. laticeps). Completion of this component is expected by the end of 2000.
Papers & Publications; Piermarini, P.M. and Evans, D.H. 2000. Effect of environmental salinity on
Na,K-ATPase in the gills and rectal gland of a euryhaline elasmobranch (Dasyatis sabma). Journal of
Experimental Biology (in review)
223
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STAR Graduate Fellowship Conference
U915604
RISK-TRADEOFFS IN DECISION-MAKING: THE MALARIA/DDT DILEMMA
Montira J. Pongsiri
Yale University
Objectives/Hypotheses: The central research question of my research is: what is the institutional capacity
to assess the risks of the use of DDT to control malaria over space and time? To answer this question, I will
study how managers of malaria control compare the risk of malaria with the risks of the methods used to
control the disease, as well as the social, cultural, economic, and political context in which these decisions
are made. The narrow definition of malaria as a problem of mosquitoes, fragmented authority, limited
resources, and uncertainties in the estimation of the risk of DDT on human health and the environment
contribute to a diminished institutional capacity to assess the risks of the use of DDT and other pesticides
for malaria control.
Rational: Persistent organic pollutants (POPs) such as DDT are long-lasting and tend to bioaccumulate
in many different media such as soil, air, water, and living tissues. Because of these properties, they can
cause adverse effects on human health and the environment at both short and long range distances from their
ovlUrlSfiHrCeS' tJ^ Timing effectiveness of DDT in the first decades of its use lead to an
overconfidence that malaria could be eradicated at one time, but it has since been realized that reliance on
SPrimHary^rr Strafegy mSy n0t bC sustainable- There is debate over the risks of exposure to
rd nc IST 5 , ^ CmX °f thC DDT dilemma Present ^amenta! changes in thinking
Ttt °HH ^^ ™ of Pesticides in vector control. An Intergovernmental Negotiating
ittee is addressing this policy problem, as it begins to carry out its mandate to develop a resolution
. .
,?S '," gOVeT™' Wh° "e decision-m^rs on the use of DDT for malaria
°° ,U '" ma'T C°ntt0' a"d effects on h™»° health and the environment; and
'"
research- ^"^ ^ personal interviews throughout Mexico
gr^e^^
assess risks over smce anH tin,- |° J"?"16"* and to lnternational organizations, that enable managers to
S^th rg 6 mstltutional infrastructure of malaria control in Mexico can
that limit the implementation of effective alternatives to DDT in endemic
areas.
ssues
issues
224
» -" SPaCK an tmC- CUrrently' ^ framework of thinki"8 about these
. Based on historical research and interviews, recommendations will be developed for a
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STAR Graduate Fellowship Conference
more holistic and systematic approach to decision-making that may meet both public health and environ-
mental/conservation objectives.
Papers & Publications: None at this time.
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U915646
TRANSITION METAL HOMEOSTASIS IN SACCHARYOMYCES CEREVISIAE
Matthew E. Portnoy
Johns Hopkins University
Objectives/Hypotheses; To investigate how the budding yeast Saccharomyces cerevisiae utilizes the
essential transitional metals copper and iron for cellular function and how the cell protects itself against these
Fenton-reactive metals.
Rationale: Iron and copper are essential trace metals required for a variety of cellular processes.
Additionally, iron and copper are Fenton-reactive metals and can catalyze the generation of hydroxyl radical
from hydrogen peroxide leading to oxidative stress and DNA, protein and lipid damage in the cell. An
mtracellular homeostasis of these metals must, therefore, be maintained to balance the requirement for the
metal for life and the toxic effects of excess metal. The baker's yeast S. cerevisiae provides an ideal model
system for studying metal ion homeostasis and oxidative stress. We and others have identified several genes
involved in iron and copper homeostasis. This work entails the analysis of two such genes and their gene
products; ATX1, a small copper binding protein and SMF3, an RAMP metal transporter regulated by iron.
An additional goal is the determination of the upstream source of intracellular copper for ATX1 .
Approach: ATX1 protein delivers copper from an unknown source to a P-type Outpace (CCC2) in the
Go gi for eventual incorporation into a multi-copper oxidate involved in high affinity iron uptake for the
cell. Additionally, ATX1 serves as an antioxidant, protecting the cell against superoxide anion effects in
cells lacking superoxide dismutase. Our approach to study ATX 1 function is to perform a structure-function
analyses usmg the recent 3-dimensional X-ray crystal structure of the ATX1 protein to select residues for
site-directed mutagenesis. The goal will be to determine which amino acid residues are important for the
copper delivery role of ATX1 and which are responsible for its anti-oxidant activity using assays distinct for
those functions. To determine the upstream source of copper for ATX1 , a reverse genetic approach will be
™. ?en" knOV!!Y t° be inv°lved in c°PPer metaboHsm will be deleted in the genome and the effect on
ATX1 function will be assessed. Gene deletions that affect the copper status of ATXlare candidates for the
upstream copper source. SMF3 was identified as a homobg to the NRAMP family of mammalian metal
transporters by sequence analysis of the recently completed genome of S. cerevisiae. A classical molecular
genetic approach will be used to determine the potential metal regulation of SMF3 and the function of the
gene product Usmg Western Blot, indirect immunofluorescence, and atomic absorption spectroscopic
analysis, the function and regulation of the SMF3 gene product will be determined.
paiM: The ATX1 structure-function analyses is complete and is published as shown below. The pre-
lim nary analyses of SMF3 ,s nearing completion and a manuscript will be prepared soon A detailed
The wn5^ H6 T ? * ™ regulati°n °f SMF3 **** function of the protein iscurrently underway.
The work to determine the source of intracellular copper for ATX1 is also underway.
1504
i^Ti P!!rtn07'M>E" Rosenzwe'g> A-c-> Rae, T., Huffinan, D.L., O'Halloran, T.V., and
1999. Structure-function analyses of the ATX1 metallochaperone. J Biol Chem 274:
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U915428
SPECIES LIFE HISTORY TRAITS, SPATIAL PATTERNING AND DENSITY
IN TROPICAL FORESTS: PATTERNS AND PROCESSES
Matthew D. Potts
Harvard University
Objectives/Hypotheses: The goal of my research is to identify and quantify the factors that control the
distribution of tropical tree species in space and time to better understand the processes controlling the
abundance and diversity of species in tropical tree communities. In addition, I hope to identify the mech-
anisms that allow rare species to increase their chance of persistence.
Rationale: An outstanding question in tropical ecology is explaining the exceeding high tree species
diversity found in the tropics. Though possible explanations abound, from stochastic random drift to
biological niche partitioning, there exist few quantitative assessments. Testing the validly ot these ex-
planations requires identifying and quantifying the processes, both biotic and abiotic, that control the
abundance and distribution of species.
On a practical level, timber harvesting and deforestation in the tropics are now ubiquitous rare species are
becoming rarer and even common species may become rare. Better understanding of ^P™*M« **
control the spatial and temporal abundance of species may reveal better land planning methods that conserve
both rare and common species.
ies distributions are influenced by three main processes: environmental heterogeneity
, and species life history trait, Using data from CTFS 50 ha U» m M alaysi and
ractons, an speces e sor
additional tree plots throughout Sarawak, Malaysia, detailed spatial analyses at both he
community level are being performed to assess the relative strength of the above process s
history tmLelatingtoovera^^
(including vegetative, phenology, and seed-biology) using original literature, herbarium speom ens»and
field measurements when necessary. In addition, field studies of seed/seed ing ^f™
species are being undertaken to obtain both demographic information as well as ^™™
at this potentialfy crucial life history stage. Finally, spatial individual based-mode
to investigate the potential ways rare species may increase their chance of persistence
form of both differential equations and iterative spatial arrays.
seedling ecology.
Pa^e^^^
infixed dipterocarp forest of northwest Borneo. Journal of Ecology (submitted)
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U915367
HETEROGENEOUS NUCLEATION OF ICE ON SOOT AEROSOL
Anthony J. Prenni
University of Colorado, Boulder
Objectives/Hypotheses; To measure the efficiency of soot as a heterogeneous nucleus for ice formation.
These results will improve the ability of atmospheric models to determine the effect of soot on cirrus cloud
formation.
Rationale: Cirrus clouds play a dual role in the earth's radiation budget, increasing the earth's albedo while
simultaneously altering emission of infrared radiation to space. It is believed that these competing effects
cause, on average, a net warming at the earth's surface. Cirrus clouds may also play a role in heterogeneous
chemistry in the upper troposphere, particularly in mid-latitude ozone depletion. Determining the conditions
under which cirrus clouds form is thus essential for understanding climate and chemistry in the atmosphere.
It is thought that cirrus clouds form naturally in the upper troposphere, when dilute sulfate aerosols cool and
become supersaturated with respect to ice. Additionally, it has been suggested that cirrus clouds could form
from heterogeneous nucleation on insoluble solids such as soot. If soot serves as an effective ice nucleus,
soot from anthropogenic sources such as aircraft emissions may play an important role in the formation of
cirrus clouds, thereby affecting the clouds' impact on the earth's radiation budget and related heterogeneous
chemistry.
Approach: We have designed an experimental technique for measuring heterogeneous ice nucleation on
soot and sulfuric acid-coated soot particles. For these experiments, a fluidized bed has been built to generate
aconstant output (~105 particles cm-3) of dry, solid soot particles in the sub-micrometer size range Particles
generated using the fluidized bed are coated with sulfuric acid using a linear temperature drop oven Using
this method, solid soot particles and liquid sulfuric acid particles pass through a flow tube oven where high
temperatures (400° C) vaporize the sulfuric acid, but not the soot. As the aerosol cools, a linear temperature
gradient across the oven ensures that each solid particle becomes coated with sulfuric acid and that sulfuric
acid does not homogeneously nucleate. The soot/sulfuric acid particles are then exposed to a predetermined
amount of water vapor to create a soot/sulfuric acid aerosol of desired composition. The aerosol then passes
mto atemperature-controlled flow tube where ice nucleation from the mixed aerosol can be monitored using
Fourier transform infrared (FTIR) spectroscopy at tropospheric temperatures and humidities. From these
experiments, we hope to determine the efficiency of soot as a heterogeneous nucleus for ice.
Status: The fluidized bed aerosol generation system has been built and characterized using a scanning
mobility particle sizer and atomic force microscopy. The flow tube system for monitoring ice nucleation has
also been used for monitoring phase changes in sulfuric acid/water and ammonium sulfate/water particles
using FTIR spectroscopy. Initial work has been done coating the particles with H2SO4 and water. Upon fully
characterizing all of the parameters related to generating the particles of interest under relevant temperature
and humidity conditions, heterogeneous ice nucleation studies will be performed at tropospheric tempera-
tures. Future studies will also examine other solid particles as possible nuclei.
Papers & Publications; Prenni, A.J., Siefert, R.L., Onasch, T.B., and Tolbert, M.A. 2000. Design and
characterization of a fluidized bed aerosol generator: a source for dry, submicrometer aerosol. Aerosol
Science and Technology, 32.
Prenni, A J, Wise, M.E., Brooks, S.E., and Tolbert, M.A. 2000. Ice nucleation in sulfuric acid and ammo-
nium sulfate particles. Journal of Geophysical Research (accepted)
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U915323
DEVELOPMENT AND DEMONSTRATION OF A HOLLOW FIBER MEMBRANE
BIOREACTOR FOR COMETABOLIC DEGRADATION OF CHLORINATED SOLVENTS
Jonathan G. Pressman
The University of Texas, Austin
Obiectives/Hvnotheses: Contamination of groundwater and soils with chlorinated aliphatic solvents is a
widespread problem. One promising approach for treating chlorinated solvents is to destroy them through
cometabolism in aerobic biological processes. This research will develop a new techno og * u£be»
challenging chlorinated solvent problems. The technology will treat chlorinated methanes, ethane and
ethenes? will handle mixed wastes containing chemicals that are toxic to the orgamsms, and will be
applicable to both contaminated water and air streams.
^rrrrr^rr^^^
maximum biodegradation rates can be obtained.
Approach: The feasibility of using microporous ho.low-f.ber membranes
^^om water withsubsequentcometabolicbiodeg^
demonstrated in our laboratory. This research is designed to develop,
.
membrane system. This will be accomplished ^-8^
performance of the hollow fiber membrane bioreactor for Beating
air, 3)
analysis, design, and operation of the process.
press)
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Pressman, J.G., Georgiou, G., and Speitel, G.E., Jr. 1999. Demonstration of efficient trichloroethylene
biodegradation in a hollow-fiber membrane bioreactor. Biotechnol Bioeng 62(6):681-692.
Aziz, C.E., Fitch, M.W., Linquist, L.K., Pressman, J.G., Georgiou, G., and Speitel, G.E., Jr 1995 Meth-
anotrophic biodegradation of trichloroethylene in a hollow fiber membrane bioreactor. Environ Sci Technol
230
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U915391
PHYSIOLOGICAL EFFECTS OF CILIATE EPIBIONTS ON A HARPACTICOID COPEPOD
Gwyn L. Puckett
Louisiana State University
Objectives/Hypotheses; The goal of my research was to determine the impact of ciliate epibionts on
harpacticoid copepod grazing, energy reserves, and sensitivity to environmental contaminants. By deter-
mining the extent of the impact of epicuticular ciliates on harpacticoids, we gain greater understanding of
meiofauna ecology.
Rationale: Harpacticoid copepods are prominent members of the meiobenthos and are an important part
of the estuarine food web, not only as consumers of microorganisms such as algae, bacteria, and detritus,
but also as a food source for larval and juvenile fish. Protozoan epibionts that colonize the chitmous surface
of copepods have been documented, but the ecological significance of these relationships is not well
understood Potential effects associated with epibiont colonization are changes in grazing rate and strategy,
decreased lipid energy reserves, and greater susceptibility of copepods to environmental contaminants.
Approach; This study concentrates on the effects of ciliate epibionts found on Couttanasp., an estuarine
harpacticoid copepod. CoMana sp. are abundant in the salt marshes along the Louisiana coast, have high
incidences of protozoan epibionts, reserve energy as neutral lipids, and have been shown to be susceptible
to hydrocarbon contaminants. The effects of ciliate epibionts on copepod grazing were investigated using
14C-radiotracer methods. Uptake of 14C-labeled cultured and insta, microalgae determined grazing rates
and differentiated between planktonic and benthic feeding. The effects of epibiont on energy reserves were
examined in a second experiment. Harpacticoids use stored neutral lipids as energy »™t"~£ *-
are available for reproduction, development and routine metabolism during periods of ^^*^
previous studies have shown that decreased lipid energy reserves in harpacticoids are assorted with
feZo-^"nt burden. Nile red, a hydrophobic fluorophore that binds to neutral^hpidswas used
examine cooeood lipid levels. Copepods are sensitive to anthropogenic contaminants, including polycyclic
S ffi*™ (PAHs), wh'ich are abundant in refined petroleum
Decreased grazing rates on microalgae and increased mortality ^.^.^
copepods exposed to diesel contaminated sediments, but responses of mdiv.dua^fc
variable. A third experiment analyzed epibiont effects on Coullana susceptibihty
contaminants, measuring epibiont influence on copepod survivorship when exposed to
sediments.
Sta.uS: All experiments have been conducted and data analyzed. I am now in the process of preparing
manuscripts for publication.
Paners & Publications: Puckett, G.L. and Carman, K.R. 1998. The effects of protozoa,.epibionts on
h4acticoid copepods in a Louisiana salt marsh. 28th Benthic Ecology Meeting, Baton Rouge, LA.
Puckett GL and Carman, K.R. 1999. Effects of protozoan epibionts on harpacticoid copepods in a
Louisiana salt marsh. 29th Benthic Ecology Meeting, Wilmington, NC.
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U915639
MULTIPLE PESTICIDE EXPOSURE: IMMUNOTOXICTY AND OXIDATIVE STRESS
Christine L. Rabideau
Virginia Tech University
Objectives/Hypotheses: The objective of this study is to examine the relationship of pesticide mixtures and
immunotoxic risk in vitro, as it pertains to the role of free radicals. Humans and other animals are exposed
to a myriad of chemicals, either concurrently or sequentially, throughout their lifetime. Often, upon meta-
bolism of these chemicals, the formation of unstable free radical intermediates or reactive oxygen species
(ROS) can result. Studies have indicated that these ROS play a role in chemical metabolism and immune
cell response and regulation. The hypothesis is that ROS and/or other free radical intermediates, generated
during the metabolism of various pesticides, mediate the immunotoxic effects of environmental toxicants
in mixture.
Rationale; The rationale of our work is two-fold: 1) exposure to two or more pesticides can result in
synergistic or antagonistic health effects mainly because the metabolism of one will affect that of the other;
and 2) since certain chemicals enhance immunotoxicity and since free radicals are suggested to enhance
immune cell dysfunction, it is reasonable to assume that these two events are interrelated. This study will
broaden our understanding of the mechanisms by which simultaneous exposure to multiple chemicals causes
immune cell (splenocyte) dysfunction in a mammalian model.
Approach; Our approach is encompassed in two specific aims. The first is to determine the extent of
immune response by C57BL/6 young adult, male mice splenocytes, in vitro, to three different pesticides and
mixtures of those pesticides. To do this, splenocytes are isolated and treated with piperonyl butoxide (PBO),
hndane, or malathion to obtain time and dose response curves. Of particular interest is the concentration of
each pesticide that yields approximately 25% immunotoxicity. Two different assays have been chosen to
assess this; the first is the alamarBiue Cytotoxicity Assay, which utilizes the fluorogenic redox indicator dye,
alamarBIue, to monitor metabolically active cells. The second assay is the "In situ Cell Death Assay" which
labels nicks in the DNA of cells undergoing cell death and is analyzed via flow cytometry After identifying
the pestictde concentration for 25% cytotoxicity, splenocytes can be treated with mixtures of two pesticides
(PBO and malathion; hndane and malathion and each pesticide alone at one concentration) The second aim
is to examine the role of reactive oxygen species in immunotoxicty by assessing the levels of oxidative
enzymes in splenocytes treated with pesticides and mixtures of pesticides. Often, when cells or organisms
are exposed to chemicals, ROS are generated and as a result, enzyme induction can occur to offer cellular
protection against these ROS. Thus, oxidative enzyme levels are often used as indicators of the oxidative
status ol cells The enzymes of interest are superoxide dismutase, catalase, glutathione peroxidase, and
glutathione reductase. Quantitation of each enzyme in the cytosolic fraction of the cells, treated with various
pesticides, will be monitored using colorimetric techniques.
Status: Immunotoxicity is being evaluated for each individual pesticide. Dose response curves have been
comp eted and pesticide mixture studies are in progress to access apoptosis due to treatment. I expect to
complete this research by August 2001.
Papers & Publications: None at this time.
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U915461
ROLE OF THE TUMOR SUPPRESSOR GENE, P53, IN PAH-MEDIATED
CARCINOGENESIS IN TWO SPECIES OF ICTALURID CATFISH
Michelle A. Rau
Duke University
Objectives/Hypotheses: This project will explore the molecular mechanisms underlying observed differ-
ential sensitivity to polycyclic aromatic hydrocarbon (PAH>induced liver cancer m two related species of
Ictalurid catfish, the brown bullhead (Amends nebulosus) and channel catfish (Ic alurus punctat^.
Specifically, this study will test the hypothesis that the tumor suppressor gene, p53, plays a cruc.
mediating the initiaton and promotion of PAH-mediated liver cancer, and that alterations in this
gene and its expression are associated with observed species differences The specific object,
project are to: 1) sequence and characterize P53 both catfish species, with an emphasis on di
basal expression between the two species; 2) determine the effect of a b^'P^ <*^^l^
on P53 mRNA expression and P53 protein expression in both species; 3) determine the effects ofBaP on
apoptosis in hepatocytes of both species; 4) examine the type, location, and frequency ofmutation,m *e
P53 gene in response to BaP exposure; and 5) examine the expression of P53 m tumor samples from
wild-caught brown bullhead.
Rationale; In contaminated North American waterways, brown bullhead
incidence of hepatic neoplasms, whereas both feral and farm-raised chai
cancers. The dichotomy of these two closely-related species is intriguing
substantial knowledge of environmental carcinogenesis. p53 is a tumor sup]
mnohu, h*if rtf all hnman cancers and is the most commonly mutated
due to environmental pollutants could grea ly• aftct thorset of
AT±^^^^
^^z^ttatt^f^*'iX^™+
dihydrodiol-9,10-epoxide (BPDE), adducts.
A™ The approach will include «t^
catfish. Following the cloning of P53, assessment of ^f.^f^j^ Jern blotting, respectively.
control and BaP-dosed fish will be performed ^^^^^^^^^^i
Mutationa, analysis of control and dosed tissue w,H *%^^J^^*^ and an
mediated PCR. Apoptosis will be assessec 1 tod , « ^^^^u^ ta ^Wcurt^ blotting
antibody-based method. An antibody to catfish p53 i will be Proau^ a
and immunohistochemistry of obtained brown bullhead tumor samples.
full-length p53 sequence in both species.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915167
PRIVATE RIGHTS IN PUBLIC RESOURCES: THE ROLE OF EQUITY
IN MARKET-BASED ENVIRONMENTAL POLICIES
Leigh S. Raymond
University of California
Objectives/Hypotheses; To show that despite its lack of attention in the literature, equity, in fact, plays a
key role in the design and implementation of market-based environmental policies, and to build a better
theoretical framework for describing how these equity arguments are presented and understood.
Rationale; Policies utilizing economic incentives rather than regulatory mandates are becoming an
increasingly popular response to environmental problems. The literature on these "market-based" policies,
as they are frequently called, provides tremendous guidance on their efficiency advantages and implications.
The literature is much more thin, however, regarding another key issue: considerations of distributional
equity This gap m the literature is surprising given the powerful distributional implications of many
market-based instruments. It is also surprising given the results of previous empirical studies that find a
significant rote for ideology (rather than self-interest) in determining the voting behavior of legislators.
While the study of efficiency ,s important to public policy, it fails to provide a complete description of the
considerations necessary for making a policy decision. That failure suggests the need for additional
scholarly work to augment the efficiency perspective.
lT diSSe*ati°n b°th JUStifl6S and fadUtateS the ^deration of equity within market-based
^X ^*^ environmental laws-the Acid Rain Title of the 1990 Clean Air Act
} 1934 Tayl°r Gra2in Act T -ed
™n o e e
«rbv± t} > , 1934 Tayl°r Gra2ing Act (TGA>- Both laws ^braced a market-based
ust^
equt a S^Zt^ft "T m I!'8™8 market'based P°lici<" by documenting the prominence of
documents TnHnt -^'^ "* Pr°CeSS in both cases" Legislative records, administrative
min andt: "Jin^r * ^-n*** a11 confi™ that much of the debate over both the acid
s 'T thC rdatiVe faimeSS °f different Pr°P°^ allocations of refined
need to consider equity' this studv *™ const™ts a framework
T^ bdn8 USed" SinCe Private ownershiP is central to the P°HcieS
th
the institut on of private property have spawned a large and diverse literature reeardinz this verv issue of
£re smlesvanc! :hi* literature' that facilitate to^ZESE^
^r SpT'ficaIIy' th,e ^^ frameworl< a"ses from a careful study of the rules for
S ^"S1^ y questions: who win receive the "ghts and to what exactly
6
ne ,, t demons^tes that in both cases no simple property
™oth atca" lor Td bate in^' Hi ^ ' ^ SpedflC but C0nflicting conceP* of property inhuenced
need for ^ ™rl un£i vi f " ^^ ™* ^'^ C°nflict Over aHocation^uggests the
^^^^•^^r^9' I"6 dial6Ctical Pf°Perty the^ rfQ-W. Hegel is a strong
under ^considera of ^ weH § ^ ^ * "^ r°bust exPla"ation of the historical allocations
warrning "' ? * ^ ** ^ CaS6S SUch as the ^0* Protocol on global
Inishing the write up of my results, and expect to file my completed dissertation by
234
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Papers & Publications: Raymond, L.S. and Fairax, S.K. 1999. Fragmentation of public domain law and
policy: an alternative to the 'shift to retention' thesis. Natural Resources Journal 39:649-753.
1997. Viewpoint: are grazing rights on public lands a form of private property? Journal of Range
Management 50:431-38.
1996. The ethics of compensation: takings, utility, and justice. Ecology Law Quarterly 23:577-622.
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U915139
LONG-TERM CHANGES IN THE SPECIES COMPOSITION OF CALANOD)
COPEPODS OFF SOUTHERN CALIFORNIA
Ginger A. Rebstock
University of California, San Diego
Objectives/Hypotheses: The goal of this project is to investigate the population responses of planktonic
species to environmental variability in the California Current System. Four questions will be addressed:
1) Are there long-term trends in the abundances of any of the selected species? 2) Are there periodic cycles
in the abundances of any of the selected species? 3) Are there groups of species that vary coherently in their
abundances? 4) Do species abundances correlate with environmental variables?
Rationale; The California Current System (CCS) is biologically rich, supporting diverse marine life, and
major fisheries. It is a highly variable system, particularly at low frequencies. For example, El Nino events
affect both the physical structure and populations in the system on an interannual time scale. Decadal-scale
events include a climatic regime shift that was observed throughout the Pacific basin in the winter of
1976-77. The responses of the biota in the CCS to this type of low-frequency environmental variability are
poorly understood. Studying past patterns of species abundances will help enable us to predict and detect
responses to future environmental change.
Approach: This project will utilize zooplankton samples and hydrographic data collected since 1951 by the
ongoing California Cooperative Oceanic Fisheries Investigations (CalCOFI) program. Selected species of
calanoid copepods will be enumerated from spring and fall samples. Copepod species have been selected
representing different families, biogeographic affinities, and trophic modes. In order to obtain estimates of
species abundances in the study region (Southern California Bight and offshore waters) samples from all
selected stations for a given cruise will be pooled prior to counting. This will average out small-scale
patehmess. Time series of environmental variables will be compared with the copepod time series.
Status: A gear comparison study and enumeration of spring samples have been completed Enumeration
of fall samples is in progress. Time series of physical variables indicating El Nino conditions have been
obtained. I expect to complete this research by the end of the year 2000.
Papers & Publications; Rebstock, G.A. A comparison of the plankton nets used by CalCOFI with respect
to the calanoul copepods, with a power analysis for the Wilcoxon signed rank test, (in review, Progress in
Oceanography)
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U915546
COST EFFECTIVE LONG-TERM GROUNDWATER MONITORING DESIGN
Patrick M. Reed
University of Illinois, Urbana-Champaign
Obiectives/Hvnothesesi To reduce the costs associated with long-term monitoring of sites with ground-
water contamination. Specifically, this research applies fate-and-transport .simulation ^,n combmat o. L wrth
discrete optimization to minimize the number of samples taken from an existing monitoring network while
accurately characterizing the contaminant plume.
Rationale: Cost and technology limitations have resulted in a shift in the design paradigm for £">"£**
^e^Ton from resource recSeryto long-tenn risk manageme*^
is a direct result of this shifting emphasis. The increasing use of RBCA is « ™
contaminants being left in place that will require long-term monitoring. Long-t
t tens or even hundreds of ex,stm
conamnants eng e n pace a
can require decades of expensive sampling at tens or even hundreds of ex,stmg momtonng
in hundreds of thousands or millions of dollars for sampling ^^"""
thatasitewithasfewasSOlong-termmonitoringwellshasoverlbillionum
be implemented.
of these designs is then evaluated in terms
geostatistics. Examples of performance : criteria include globa
ing, or uncertainty estimates attained using indicator kngmg. . Fhnc8S values are then
to compute a fitness (or measure of the quality) of each potential ^P^^J^e and evolve in later
usedbyVGAtodetenHinewhichindi^^^
generations in a process analogous to Darwinian evolut, on/hem^f^Ae"estoseveral optimal
iterations of evolving new populations of potential sampling plans until the GA converg
or near-optimal sampling designs.
Stec.^.^-^i.^'-x-.j^^'S^^
framework. This effort is expected to quantify the Pareto frontier, wfticn p
cost and uncertainty for sites undergoing long-term monitoring.
R «= and Valocchi A J 2000. Cost effective long-term
gapers & Publications: Reed, P Ml^ Bf ^"hm and glob'al mass interpolation. Water Resources
groundwater monitoring design using a genetic algontnm dim g
Research (submitted)
Reed, P., Minsker, B.S, and Goldberg, D.E. 200, Designing a competent simple genetic algorithm for
search and optimization. Water Resources Research (submitted)
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U915183
TRADE AND ENVIRONMENTAL POLICY: AN ANALYSIS
OF THE TECHNOLOGY EFFECT
Valerie Reppelin
The George Washington University
Objectives/Hypotheses: This research is an attempt to further our understanding of the main linkages
between trade and environmental quality. The approach follows a recent trend in the trade and environment
literature that decomposes the impact of free trade on environmental quality into three main effects: the
scale, composition and technology effects. This research focuses on the technology effect, that is, the
relationship between trade openness and the adoption/diffusion of clean technologies. More specifically,
I attempt to verify the existence of the technology effect (i.e., does trade encourage faster adoption/diffusion
of clean technologies) both theoretically and empirically.
Rationale; The research focuses on the technology effect for two primary reasons: 1) this effect has been
virtually ignored in most of the literature, and 2) the technology effect is the only effect that suggests a
positive correlation between trade and environmental quality. This point is important as it would, if verified,
make the case for unilateral trade liberalization much stronger. It should at least reduce the need to promote
protectionism in the name of the environment.
Approach; On the theoretical front, an integrated model of trade and environmental policy is developed
to examine whether trade encourages faster adoption/diffusion of cleaner production techniques Instead of
focusing on the standard Heckscher-Ohlin framework, I follow a different approach (Mussa 1974) which
assumes that, in the short run at least, capital goods are sector specific. In this framework lexamine how
environmental regulations affect trade patterns and how trade itself affects specific factor returns and the
incentive for shifting technologies across countries and across industries. The empirical component of the
research compares the speed of diffusion of a cleaner steel innovation, the electric arc furnace (EAF), in 30
steel producing countries over 25 years. A partial adjustment stock model is used to examine the diffusion
of EAF technology. Specifically, the hypothesis that the EAF technology is diffused faster in countries that
have more open trade regimes is tested. Six measures of trade openness are used in the analysis.
Status: lam now writing the final version of the dissertation, trying to reconcile the seemingly contradictory
results of the empirical and theoretical exercises. I intend to graduate in summer 2000.
Papers & Publications; Reppelin-Hill, V. 1999. Trade and environment: an empirical analysis of the
technology effect in the steel industry. Environ Econ Management 38:283-301.
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STAR Graduate Fellowship Conference^
U915614
PHYSICAL CIRCULATION OF THE NEUSE RIVER ESTUARY (NRE)
AND ITS CONTRIBUTION TO THE OCCURRENCE OF FISH KILLS
Janelle V. Reynolds-Fleming
University of North Carolina, Chapel Hill
Qbiectives/Hvnntheses: It is hypothesized that fish kills in the Neuse River Estuary (NRE), NC, occur
when meteorlogical conditions cause hypoxic/anoxic water from the deeper central part of the estuary to up-
well and advect into shallower parts thereby trapping fish in the creeks and along the shore with no escape
route.
Bationaie: The Neuse River Estuary (NRE), a shallow, lagoonal/rivenne estuary located east of New Bern
North Carolina and extending eastward into the Albemarle-Pamlico Sound system, has been he focus of
recent outbreaks of nuisance algal blooms, hypoxia, toxicity, and fish kills associated with ^^^
quality. Large fish kills and declining water quality can have a devastating effect on local ouns* and
fishery economy, as well as disrupting the natural state of the environment. The circulation ofthc NRE play
an integral role in the water quality of the NRE by controlling flushing rates an Residence times of e xc»
nutrients as well as advecting dissimilar hydrographic volumes of water within the estuary ™e cwutoon
in this estuary is primarily dominated by freshwater discharge and meteorological *f^ »*£*£*
^s±K,2^t£^^
cproeoteenrewaerc
movement of low dissolved oxygen water into shallower areas, but represent a hmried spa ^.al area- A
hydrodynamic/oxygentransportmodelwillbedevelopedth^
study area. This model will be calibrated with empirical data. Once calibrated, the model w.11 then ^ed
to simulate circulatory and dissolved oxygen conditions under varying forcing conditions (,.e, fresh water
discharge, varying wind directions and speed).
Status: The ADCPs were maintained during the winter and spring of 2000 and
The novel profiling platforms will be in place by May 2000 and will be mamtained ^^^^
A 2-D hydrodynamic model has been applied to the NRE with mixed results. A 3-D model that includes
dissolved oxygen transport is currently being developed.
lMilta^
characteristics of the NRE. (submitted to Estuarme, Coastal and Shelf Science)
Reynolds-Fleming, J.V. and Luettich, R.A. 2000. Investigation of circulation in the Neuse River Estuary,
NC. Poster for WRRI conference, Raleigh, NC.
Reynolds-Fleming, J.V. and Luettich, R.A. 1999. Circulation characteristics of shallow estuary plagued by
Water quality issues. ERF Conference presentation, New Orleans, LA.
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U915559
CHARACTERIZATION OF REDUCTIVE-DECHLORINATING MICROBIAL
COMMUNITIES USING A COMBINATION OF FLUORESCENT IN SITU
HYBRIDIZATION AND PCR-BASED MOLECULAR TOOLS
Ruth E. Richardson
University of California, Berkeley
Objectives/Hypotheses; The objective of this project is to understand the microbial community structure
of a mixed culture that fully dechlorinates chlorinated aliphatic hydrocarbons to ethene. Additional
characterization of a partially dechlorinating culture (which produces vinyl chloride as the primary
end-product) will provide evidence as to which populations are essential for the final and most important
(from a public health standpoint) dechlorination step that converts vinyl chloride to ethene. By using a
combination of molecular tools it is possible to get a more complete picture of community structure than any
single method would allow.
Rationale; In recent years, novel approaches have emerged that address the remediation of sites
contaminated with chlorinated ethenes—namely perchloroethene (PCE) and trichloroethene (TCE). One
such approach employs microorganisms with the unique physiological capacity to use these compounds as
terminal electron acceptors under anaerobic growth conditions. While a number of researchers document
biological reductive dechlorination by mixed cultures, identification of putative degraders has traditionally
relied upon isolation of pure cultures of microorganisms. Researchers who have isolated a pure culture
capable of full dechlorination (with ethene as the end-product) report that cell free extracts of dechlorinating
mixed cultures must be added to keep such isolates alive. It appears that chemical interactions amongst
members of dechlorinating mixed cultures are vital to the overall degradative capabilities of the culture.
Methods that allow identification of the various members of mixed communities "as is" may enhance the
understanding of the symbioses occurring.
Approach: In this study, two dechlorinating mixed cultures were characterized and compared by a
combination of 16S rDNA-based molecular methods: terminal restriction fragment length polymorphisms
(T-RFLP), RFLP and sequencing of individual clones from clone libraries constructed from amplified
community DNA, and fluorescent in situ hybridization (FISH). The cultures originated from a soil sample
obtained at Alameda Naval Air Station that was contaminated with a combination of hydrocarbons and TCE.
One culture completely dechlorinates TCE and PCE to ethene, while the second daughter culture de-
chlorinates only to vinyl chloride (VC, a known human carcinogen).
Status: Clone libraries were constructed for each culture using Bacterial primers. Predominate sequences
obtained form the original (completely dechlorinating) culture were closely related (> 98% identical) to
Eubactenum limosum, Desulfovibrio sp, and Dehalococcoides ethenogenes—the only known isolate
capable of complete dechlorination. FISH with group-specific probes suggest that members of the
Cytophaga/Flavo-bacterium/Bacteriodes cluster are also significant despite their relatively minor presence
in the clone library. By comparing the T-RFLP profiles of the two cultures, it was apparent that significant
differences existed between the two communities. RFLP analysis of clones in the libraries supported this
conclusion. Specifically, only one of the four main RFLP patterns (for Desulfovibrio) from the parent
culture was observed in the daughter culture. Most notable was the absence of the ribotypes associated with
Dehalococcoides ethenogenes and Eubacterium-suggesting that the latter may provide Dehalococcides with
biochemical factors necessary for its growth and function. In the daughter culture, ribotypes associated with
various gamma and beta proteobacteria dominated the clone library. This suggests that a variety of
phlyogenetically distinct microorganisms may be capable of partial dechlorination whereas only a small
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subset may be capable of the final dechlorination of vinyl chloride to ethene. Two *™^%£*T°™
specificforEubacteriumlimosumandtheotherspecificforDehalococco^es-were designed andare being
applied via FISH to quantify the populations of these organisms in the two mixed cultures.
Papers & Publications: Richardson, R-E-* Bhupathiraju, VX., Song, 1^
IT! 2000. Molecular characterization of a TCE-dechlorinating anaerobic mixed culture Abstracts of the
American Society of Microbiology-lOOth General Meeting, Los Angeles, CA. (in press)
^hardson, R.E,Bhupathi^
zation of a mixed culture capable of full reductive dechlorination of TCE using a combination of FISH, 1 6S
rDNA clone libraries, and T-RFLP analyses, (in preparation)
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U915427
CARBON STORAGE AND THE TIMING OF LEAF FLUSH
Renee A. Richer
Harvard University
Objectives/Hypotheses; The timing of leaf flush in trees varies widely among species. The cues that regu-
late phenological events have often been considered to be environmental factors or endogenous rhythms. I
am examining the role that stem carbon stores play in regulating the timing of leaf flush.
Rationale: Recent evidence suggests that many environmental factors may cue leaf flush. This may seem
confusing as there seems to be no overriding principle. However, evidence is mounting that most
env,ronmental factors affect the amount of carbon stored in the stem. Hence, many environmental factors
may act via carbon stores.
Afipioach: Using a two pronged system of research ( observation and manipulation), I am assessing the
role that carbon stores play in the timing of leaf flush. I am observing ten native tree species that exhibit a
range of flush patterns. Using a model tree species, I am using a series of manipulations to alter carbon
levels to assess the effect on leaf flush.
SSSiV 3m rT1* ^ •he,third ^ °f the Pr°ject r have been followingten n*fre species intensely
as well as conducting manipulative experiments.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915350
SEQUENTIAL ANAEROBIC/AEROBIC TREATMENT
OF POLYCHLORINATED BIPHENYLS IN SOIL
Julia D. Rogers
Colorado State University
Objective/Hypotheses: Although their production and use has been banned in the United States since
1977, PCS contamination is ubiquitous (216 NPL sites) and (usually) consists of a mixture of congeners with
a range of degree of chlorination. Anaerobic dechlorination removes chlorine substituents, but only from
highly chlorinated PCBs, Conversely, aerobic degradation of PCBs transforms only those congeners with
low chlorine number. A combination of anaerobic and aerobic treatment phases is a promising solution to
the problems encountered with each treatment phase alone, yet almost nothing is known about specific
parameters critical to the success of this process. Our research will determine the relationships between
engineering variables, microbial community composition, and PCB mineralization in the engineered
bioremediation of PCB-contaminated soil. Our hypotheses are: 1) microbial community composition,
engineering variables and observed PCB reductions can be correlated; and 2) the overall reduction in PCB
mass achieved by sequential anaerobic-aerobic treatment will be greater than achievable by either process
alone.
Bationale: Environmental polychlorinated biphenyl (PCB) contamination is often comprised of mixtures
of congeners with a range of degree of chlorination. Complete biodegradation of PCB mixtures is rarely
achieved, since highly chlorinated PCBs are not metabolized under aerobic conditions and less chlorinated
congeners are not degraded by anaerobic microorganisms. Sequential anaerobic-aerobic treatment for PCB
contamination is promising, yet little is known about specific parameters important for their successful
bioremediation. Most of the work in this area has focused on a "black box" approach to enhancement of
PCB transformation with little insight into the actual microbial processes at work,
ABfiroach: Both batch and flow-through microcosm experiments will be performed. The batch microcosms
will be used to screen several engineering parameters (electron donor addition, initiation of aerobiosis after
anaerobic treatment, cometabolite addition during the aerobic phase) for their effect on degradation of PCBs
and microbes. Flow-through microcosms that approximate the complexity of natural soil systems will be
used to test combinations of the most promising treatments from the batch microcosm tests with the
additional parameter of varying lengths of treatment phases. We will use information about microbial
community composition and activity to characterize the effect of each engineering parameter on PCB
degradation. To do this, a combination of genotypic and phenotypic microbiological techniques will be
utilized. Phospholipid fatty acid analyses will be used to determine total biomass levels and broad-based
changes in microbial community structure. A competitive polymerase chain reaction procedure will allow
for quantitation of specific genera and degradative genes.
§*atus: In this laboratory-scale investigation, sandy soil with non-detect amounts of PCBs, but previous
exposure was spiked with 3-4 selected congeners. In microcosms run anaerobically.dechlorination of several
hexa-chlorobphenyls to penta- and tetrachlorobiphenyls by indigenous organisms was detected in soil
microcosms within 16 weeks of incubation. The dechlorination pattern was strongly dependent on the
congener being degraded in addition to the electron donor utilized. For example, glucose induced ortho
dechlorination of 234-234 to 34-34, and both meta and para dechlorination of 245-245 to penta-
chlorobiphenyls with a further meta dechtorination to a tetrachlorobiphenyl. Significant differences in
community structure was observed between different electron donor treatments. Both 2,3',4'-PCB and
biphenyl were completely degraded in aerobic microcosm experiments in 7 weeks. Microcosms not amended
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STAR Graduate Fellowship Conference
with biphenyl showed decreased degradation rates compared with those amended with biphenyl during the
aerobic phase. Although total biomass remained constant in all treatments (as shown by PLFA), changes in
microbial community composition occurred in biphenyl- amended microcosms: the anaerobic microbial
community decreased in size and there was a subsequent increase in aerobic lipid biomarkers. Bottles with
no amendment showed no difference in community composition from time zero samples.
Papers & Publications; DuTeau, N.M., Rogers, J.D., Bartholomay, C.T., and Reardon, K.F. 1998.
Species-specificoligonucleotides for enumeration of Pseudomonas putida F1, Burkholderia sp. Strain JS150,
and Bacillus subtilis ATCC 7003 in biodegradation experiments. Applied and Environmental Microbiology
64(12):4994-4999.
Reardon,K.F., Mosteller, D.C., and Rogers, J.D. Biodegradation kinetics of benzene, toluene and phenol as
single substrates and mixtures by Pseudomonas putida Fl. Biotechnology and Bioengineering (in press)
Rogers, J.D. and Reardon, K.F. Modeling substrate interactions during the biodegradation of mixtures of
toluene and phenol by Burkholderia species JS150. Biotechnology and Bioengineering (in revision)
Rogers, J.D., DuTeau, N.M., and Reardon, K.F. Use of 16S rRNA to investigate the microbial population
dynamics during biodegradation of toluene and phenol by a binary culture. Biotechnology and Bio-
engineering (in revision)
Rogers, J.D., DuTeau, N.M., and Reardon, K.F. Effect of electron donor amendment on the microbial
ecology and anaerobic degradation patterns of polychlorinated biphenyls in soil, (in preparation)
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STAR Graduate Fellowship Conference
U915650
INDIVIDUAL GROWTH RATES AND POPULATION DEMOGRAPHY
OF WHITE-FLOWERED TRILLIUM (TRILLIUM GRANDIFLORUM) ACROSS
GRADIENTS OF LIGHT, FERTILITY, AND DEER BROWSING PRESSURE
Thomas P. Rooney
University of Wisconsin, Madison
ObiectivEs/RypnthESEs: I propose to determine the effects of deer browsing on the forest herb, the large
white-flowered trillium (Trillium grandijloruni). I propose to: 1) determine if trillium growth reflects an
overcompensatory or under-compensatory growth response to browse damage, and how this response is
mediated by soil fertility, light availability, and the reproductive history of the plant; 2) find the determinants
of plant selection by browsers; 3) determine how browsing, relative to other environmental factors, affects
the population structure and growth of trillium; and 4) determine the impacts of the loss of populations on
genetic diversity.
Rationale: Changes in ecosystem structure and composition, land use, and management policy over the past
century have created favorable conditions for white-tailed deer populations. Deer now exist at densities
several times higher than they did during presettlement times, and now act as a 'keystone' herbivore.
Afifiroach: In 1997,1 established 27 study plots throughout northern Wisconsin and the western portion of
Michigan's upper peninsula. In each study plot, I recorded the spatial location and height of all 3-leated
white-flowered trilliums, and the location of all one-leafed trilliums. The 2000 plants in these plots have
been monitored every year. Soil and light measurements were taken in each study plot, and local browsing
pressure was assessed. Four additional study plots were added in 1998 for artificial defoliation experiments.
Status: All fieldwork is complete, and I am in the data analysis and writing phase of my research.
Papers & Publications: Rooney, T.P., Steven, J.C., and Boyle, O.D. 1999. Deviations from expected
height-diameter isometry in Trillium grandiflorum. Published Abstract, Annual meeting of the Society for
the Study of Evolution.
Rooney, T.P. and Waller, D.M. 2000. The effects of reproduction and experimental defoliation on the
relative growth rate of the deciduous forest perennial herb Trillium grandiflorum. Oecologia (submitted)
Rooney, T.P. Functional responses of white-tailed deer (Odocoileus virginaianus) to white-flowered tril-
lium (Trillium grandiflorum) at three spatial scales. Oecologia (submitted)
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STAR Graduate Fellowship Conference
U915345
MECHANISMS DRIVING THE EXTIRPATION OF A DESERT FISH SPECIES
Jonathan A. Rosen field
University of New Mexico
Objectives/Hypotheses; To identify the forces contributing to extinction via hybridization among animal
species in the wild. Replacement of rare endemic species by their hybrids with introduced congeners are
driven by biological mechanisms. These mechanisms may include mating preferences that erode species
boundaries and/or differential competitive ability and life history attributes that favor spread of hybrids
through the native population.
Rationale; Manv sPecies are threatened with extinction as a result of hybridization and introgression
(genetic assimilation). Indeed, introgression is second only to habitat destruction as a mode of extinction
among plant and fish species. Though hybridization and introgression are common threats, the mechanisms
that promote these phenomena have received little attention. By studying mechanisms of introgression, we
may learn more about why some species hybridize and backcross successfully while others do not, and we
may gam insight into conservation techniques that prevent (or even reverse) genetic assimilation.
ABfiroMh: I am using the explosive introgression between the Pecos pupfish and the sheepshead minnow
(genus: Cyprmodon) as a model system for studying mechanisms of hybridization and introgression. Female
matmgpreferenceswillbeevaluatedinexperimentswherefemalesareexposedtomalesoftheirownspecies
and males of a competing form (another parental species or hybrids). One experiment will isolate visual
preferences and another will test for olfactory recognition and preference. Male-male competitive ability
w,l be measured to determine if there are differences between the genotypes in their ability to gain and hold
ST? IT H S™T' ng UranCe (a meaSUre °f eC°logical *™P*itiveness) will be evaluated in the
f nvhrn-f ^? y> hlStory attnbutes of the Parental ^d hybrid forms will be measured to determine
if hybrid life history promotes their spread in the wild.
fSfeolftl6 C°mPf 6ted CrltiC,al experiments includin8; male-™le competition, female visual preference,
female olfactory preference, and swimmmg endurance. Sexual selection clearly plays a role in the formation
tthS
the hybnds probably contributed to the rate of hybrid spread through the Pecos pupfish population. Life
history experiments and growth trials will be completed this summer. popuiauo
R°,Senfield' J^> Todd, T., and Greil, R. 2000. Asymmetric hybridization and
nb- ,, .
AmefkaT?ishert S * J ?°* ** ^^ ^^ * ** Uurentian Great Lakes' Transactions of the
American Fisheries Society, (m press, expected publication date May 2000)
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STAR Graduate Fellowship Conference
U915346
a i x ja JK? j.1 v^i*. V^J. .•. -»A.*-*"".«-^.«-* • •*-» *•-—• •—-1 ™ AVrf-AA ^»*J
WITHIN WESTCHESTER COUNTY'S CROTON WATERSHED PLAN
U915346
METHODS FOR OPTIMIZING MUNICIPAL ENVIRONMENTAL ORDINANCES
,^,-^^^.T «-«morr./-iTTET> /-'rkTTiwTVC fi) nTnN WATERSHED PLAN
Joyce E. Rosenthal
Columbia University
Objectives/Hypotheses; To identify methods for preserving the quality of New York City s (NYC s) water
supply through improved municipal regulations governing land development, while reconciling the goals
of environmental protection with economic development in densely developed NYC watershed regions.
Rationale: Northern Westchester County supplies an important portion of NYC's drinking water. The
Croton Watershed encompasses all or parts often municipalities in Westchester County, totaling 177 square
miles, or 39% of the County's total area. Pollutants contributed by urban runoff and erosion of sediment
from land development activities threatens the quality of this water supply. Westchester County recently
began the first year of a 4-year intergovernmental effort to develop the "Comprehensive Croton System
Water Quality Protection Plan." This process is a cooperative effort between the County, NYC, state and
local agencies including the NY State Department of Health, and the ten municipalities in northern
Westchester that fall within the Croton Watershed boundaries. A major objective of this planning process
is to recommend specific measures to be taken by watershed municipalities to improve water quality m the
Croton system while protecting community needs.
Abroach: Research focused on several related areas: 1) "Home rule" fundamentally affects development
practices in Westchester County. Municipalities have primary legal authority to regulate all development
within their boundaries, as defined by state and federal law; the County has pnman ly an advisory- «fc Thus
ordinances that regulate land development in the ten municipalities were analyzed and compared, regarding
the amount of environmental protection they afford and consistency with requirements in other watershed
towns. Local requirements pertaining to steep slopes protection, erosion and sed.ment Control and
stormwater management were analyzed for their content and placement with town '°d%2) ^hePIa°-
ning is by definition transboundary and intermunicipal, since watersheds are natural features;
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STAR Graduate Fellowship Conference
U915322
GENETIC ENGINEERING OF A RADIATION RESISTANT BACTERIUM
FOR BIODEGRADATION OF MIXED WASTES
Heather M. Rothfuss
University of Washington
Objectives/Hypotheses; Equip the radiation resistant bacterium Deinococcus radiodurans with bio-
degradative and protective abilities through genetic engineering in order to remove toxic organics from
mixed wastes.
Rationale: A survey of 91 of 3000 U.S. Department of Energy waste sites in 1992 indicated that about 32%
of soils and 45% of groundwater at these sites were contaminated with mixed wastes, or combined radio-
nuchdes, heavy metals and organic pollutants. Because of the complexity of mixed wastes, conventional
separations, if physically possible, are usually so dangerous or expensive that they are not feasible One
treatment strategy would be to remove one or more of the dangers of the waste so that the remaining portion
may be treated and disposed of with added safety and flexibility.
AfiEIoach: Bacteria that have the ability to degrade a broad spectrum of organics or convert them to
non-toxic intermediates are ubiquitous in nature. However, in the presence of moderate to high level
ionizing radiation, most organisms die or mutate because of the inability to quickly and correctly repair DNA
damage caused by the radiation. The non-pathogenic bacterium Deinococcus radiodurans Rl is an excep-
hTve theTnTent ' iTT*^ ** "T"' * ^ * **""* *®* * ****** tOXiC °T^CS- EW™S that
o?*^
T'h ,?, f of expression, stability and effect of the genes on Rl will be evaluated. This
can be used to formulate and optimize treatment strategies using the recombinant bacterium.
Crt0?rd pr°mote/SuhaS bee" deVel°ped for cloninS in R1 ' As a Preliminary test of the
m f w 7" M1168 ^ t0 ^ °rth° diox^enase (TOD) operon have been cloned into
the Rl genome as a stable double crossover insertion. The expression levels compared favorably to those
S °f ^ T°D 8e:eS' ^ ^ C0nsiderably higher than reported in Rlby previous
^^ ""^ °Xygenases to imProve substrate capabilhies and
aHW^l!fC?ti0nS; nMeJma R" R°thfUSS' H" °eWin' L" and Lidstrom' M'E- 2000. Promoters in the
radioresistant bacterium Deinococcus radiodurans. (in preparation)
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STAR Graduate Fellowship Conference
U915372
DO ENEMIES OF HERBIVORES SHAPE THE EVOLUTION OF PLANT TRAITS?
WILD COTTON AND EXTRAFLORAL NECTARIES
Jennifer A. Rudgers
University of California, Davis
Objectives/Hypotheses: To understand the evolutionary implications of indirect interactions among
organisms, I am using a wild cotton species, Gossypium thurberi, and its associated insect herbivores and
ants as a model system to address the specific question: Do enemies of herbivores shape the evolution of
plant traits?
Rationale: Conceptual Advances in Evolutionary Ecology. Indirect interactions occur commonly in nature
and are known to be important components of the ecological dynamics of many communities (Wooton
1994). How traits of organisms that interact indirectly evolve in this community-level context is not well
understood (Miller and Travis, 1996). I focus on indirect interactions between plants and the enemies of
their herbivores. Despite a number of studies that demonstrate a benefit to plants from the enemies of their
herbivores, little is known about the evolution of indirect plant defenses, which occur when plants attract
herbivore's enemies as a defensive strategy against herbivores.
Applications in Agriculture. Indirect plant defensive traits may play important roles in reducing damage to
crops. Because agricultural crops are bred primarily for direct defense against herbivores, indirect defense
is often overlooked and may be lost under current crop breeding protocols. By investigating the ecology of
plant-herbivore interactions on a close relative of cultivated cotton, new insights into alternative methods
for controlling pests of cotton crops can be gained.
Approach: To address the question: Do enemies of herbivores shape the evolution of plant traits? lam
investigating the following sub-questions: 1) Is there heritable variation in the extrafloral nectaries? 2) Does
damage by herbivorous insects decrease plant fitness? 3) Do ants increase plant fitness by reducing herbi-
vore damage? 4) Do extraflora! nectaries mediate the interaction between the ants and the plant? Experi-
ments are being conducted on native populations of Gossypium thurberi in the Sonoran Desert of SE
Arizona. Results from these experiments will determine whether variation in extrafloral nectaries translates
into variable plant fitness through an indirect interaction between plants and ants.
Status: Results from 1998 and 1999 are consistent with the hypothesis that the evolution of the extrafloral
nectary trait is shaped by ants. Ants increase plant fitness correlates (seed and flower production) due to a
reduction in herbivory. Furthermore, ants respond to the availability of nectar resulting in lower seed
production when nectar is unavailable to ants, but this response is variable in space. This research provides
the first experimental evidence suggesting that traits involved in indirect interactions between plants and
their herbivores evolve in response to selection pressure from the herbivore's enemies.
Papers & Puhlicatinns: Rudgers, 3.A. 1999. Do enemies of herbivores shape the evolution of plant traits?
Wild cotton and extraflora] nectaries. 1999 Annual Combined Meeting of the Ecological Society of America
Bull Ecol Soc Amer 80(3);176.
Rudgers, J. A. 2000. Mechanisms underlying increased seed production of Gossypium thurberi (Malvaceae)
in the presence of ants. 2000 Annual Combined Meeting of the Ecological Society of America, (submitted
and accepted)
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U915431
SIMULATED EFFECTS OF ELEVATED NITROGEN DEPOSITION
ON COLORADO ENGLEMANN SPRUCE FORESTS
Heather M. Rueth
Colorado State University
Objectives/Hypotheses: Field survey results of 12 similar old-growth Englemann spruce stands suggest
that current levels of nitrogen (N) deposition are altering forest biogeochemistry on the east side of the
Colorado Front Range. It is difficult in surveys to control potentially confounding factors CENTURY a
biogeochemical cycling model, was used to address whether elevated N deposition can explain observed
differences in N pools and cycling rates between high and low N deposition sites.
Rationale: Factors that could cause the observed differences in N cycling and N pools include species
composition, elevation, aspect, parent material, site history, soil texture, climate, and N deposition. Species
composition, elevation, aspect, and parent material were controlled during site selection. A modeling
approach allows one to control potentially confounding factors and focus on the effects of N additions.
: A control and fertilization simulation were compared. Atmospheric N additions were 0.2 kg
e
. aons were .
N wa, JH H ? t,e T r T*11 ^ ^ ^ simulation' which is considered background. Additional
n -T **"* ^ laSt ' °° ym' Human P°Pulation in *™* ^ne counties
N wa, H H t, r ' .
nlrincl H n -T **"* ^ laSt ' °° ym' Human P°Pulation in *™* ^nge counties
has increased exponent.ally since 1900. Assuming increases in N deposition paralleled population, a curve
TePN hTlTr 7Cre^N^P°siti- was ft to the population growth curve with N deposition reaching 4.7
Jcg N ha- 1 yr- 1 in 1 995. This curve
hlr
ha- 1 yr- 1 in 1 995. This curve was used to determine N inputs.
N additi°ns and the Pas^e SOM pool was
^
differences between high and low N
, E.J., Minear, J.T.,
reSP°nSeS to ""r°gen deposition in the Colorad° Front I^nge. Ecosy^ems
'M' '"' Pntia' "itr°gen mtaera^*» ^ "Mncation in American beech
s.hongradientinthenortheasternUS.EcologicalApplications
S± of^RScf ^ "^ *-•- ln "*<— ' C*— Canadian
250
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STAR Graduate Fellowship Conference
U915593
THE EFFECT OF WINDTHROW DISTURBANCE AND SALVAGE LOGGING
ON NUTRIENT CYCLING IN A CONIFEROUS FOREST ECOSYSTEM
Cristina M. Rumbaitis-del Rio
University of Colorado, Boulder
ves/HYpntlieses: The goal of this study is to characterize the short-term effects of large-scale
windthrow disturbance and subsequent salvage logging activities on forest nutrient cycles. The study site
is the Routt National Forest in Northern Colorado. This mature, spruce-fir forest experienced a large (>8,000
hectares) windthrow disturbance in October 1997. A portion of the blowdown has been salvage logged over
the past 2 years.
Rationale: This study will evaluate the hypothesis that nitrogen availability will be lower in logged areas
relative to areas of intact forest and areas of blowdown forest. Nitrogen is of particular interest because this
nutrient may be factor limiting forest growth. The results of this study are expected to help elucidate the
controls on the biogeochemical response to natural and anthropogenic landscape disturbances. Finally, it
is hoped that this study will integrate with concurrent studies of the blowdown in the Routt National Forest
to provide a more complete understanding of the consequences of natural storm disasters and human
mitigation activities.
Afiproach: Experimental plots were installed in August 1999 in areas of intact forest, areas of blowdown
forest, and in recently salvage-logged areas. Soil samples were collected from each plot ,n order to measure
the following physical and chemical properties of the soil: soil moisture, soil organic matter content, carbon
to nitrogen ratio, carbon concentration, nitrogen concentration, PH, and soil texture. Furthermore nitrogen
mineralization rates were calculated in each plot using the in situ buried bag method for August through
November 1999.
Status: Further research will focus on the nutrient retention capabilities of areas experiencing differing
intensities of salvage logging. It is anticipated that this project will be completed in the spring of 2002.
Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915244
SHALLOW INTERMITTENT SAND FILTRATION: DESIGN OPTIMIZATION
AND EFFLUENT CHARACTERIZATION FOR REUSE
Loret M. Ruppe
University of California, Davis
Objectives/Hypotheses; The goal of this research is to optimize the critical design parameters of media,
dosing frequency, and media depth for intermittent sand filters (ISFs) for the treatment of residential
wastewater. The improvement of these filters will lead to lower costs of construction and operation and
reduce space requirements, thereby improving the feasibility of ISFs as an option to treat domestic
wastewater on a small scale. Characterization of the effluent from these systems will enable informed
decisions about beneficial reuse.
Rationale: Treatment of domestic wastewater for approximately 25 percent of Americans is performed by
onsite septic tanks and soil absorption and other rudimentary onsite treatment systems, and many of these
systems are failing, resulting in the contamination of groundwater with human pathogens. Intermittent sand
filters are increasingly used to augment septic systems to achieve adequate treatment of domestic
wastewater. Interest has been renewed in the use of this technology as shallower media depths, higher
loadingratesandsPeciaIapplicationsareProvidingadequatetreatmentofPrimaryeffluent.Recentresearch
on the use of highly porous sintered glass has shown improved removal of virus; however the cost of
sintered glass makes its use prohibitive on the large scale. One focus of this research is to find a material
with similar physical characteristics that can be economically used in single or small community systems.
Two critical design parameters, optimal media depth and dosing frequency, will also be investigated for the
selected media. The quality of the optimized ISF effluent has implications for allowable methods of
wastewater reuse. Effluent quality will be evaluated for disinfection requirements and reuse applications.
AjBEIM£h: In the first stage of research, filter media will be evaluated for nutrient and virus removal.
^Zl T^H ^ 7S Wi ^ C0r;structed "* a varietv ^ fi^er media tested for nutrient and viral
removal. The filter media under consideration for testing include sintered glass rings, diatomaceous earthen
cylinders lava rock, pumice, and sand. After the relative performance of each type of media has been
evaluated, further experiments will be performed using the most promising medk to determne optimal
dosing frequency and filter depth for nutrient and virus removal. The relationship between meTdepth and
dosing frequency will also be investigated. Field verification of significant finds using fieklscale systems
fffluln frl 7, P ^ W1u ^ C°ndUCted in thC S6COnd Sta*e Of this study- I" the third stage, the
±±rt±^
according to the proposed California water recycling criteria and the U.S. EPA guidelines for water reuse.
^ESS
will be characterized for disinfection requirements.
in iaboratory c°iumns>
w s > ™ ™™y
the field-scale systems. It is anticipated that experimental work will be completed by December 2000.
Papers & Publications: None at this time.
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U915558
ENVIRONMENTAL BENEFITS AND IMPACTS OF JAPANESE
INTERNATIONAL ENVIRONMENTAL AID
Daniel J. Rutherford
Stanford University
Obiee«v.,/Hvnn.l.e,es: To investigate the environmental benefit, and impact, of Japanese international
environmental aid to countries in Southeast Asia.
Rationale: Future efforts are necessary to clarify the rationale for this research.
taken toward answering the research question will be determined at a later date.
^Currently.courseworktosa^^^
specific choice of a research topic as well as the research design will begin in the fell
Papers & Publications: None at this time.
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U915648
GENETIC VARIATION IN PHRAGMITES A USTRAL1S
Kristin Saltonstall
Yale University
Objectives/Hypotheses: This research examines the question of whether or not a non-native strain of
Phragmites australis might have been introduced to North America, thus contributing to its spread. The
objectives of this study are to examine the following questions: 1 ) What is the distribution of extant popula-
tions of P. australis across North America and how are they related? 2) How are historic and present
day populations of P. australis throughout North America related? 3) How are Phragmites populations from
different parts of the world related?
Rationale; The widespread invasions of P. australis over the past century have had significant impacts on
the ecological integrity, function and biodiversity of wetlands in North America. Historical records and
fossil evidence indicate that the species has been present in North America for thousands of years and
probably grew in mixed species communities in coastal marshes and other wetland habitats. Today, it
typically grows in dense monocultures, which exclude other plant species and may change wildlife utilization
of wetland habitats. Changes in land use patterns, hydrologic regimes, pollution, and urbanization of the
landscape have all been proposed as potential factors that have facilitated the spread of the species.
Alternatively, it has been hypothesized that an aggressive, competitively superior genotype of Phragmites
has been introduced to North America and displaced former populations as well as entered new areas.
Recent attempts to describe the genetic makeup of Phragmites populations in North America have had
limited sample sizes and been restricted to a local or regional focus. Besitka (1996) in a study examining
guard cell size as an indicator of ploidy level, suggested that there has been a shift from a 6x type to 4x over
the past century. Isozyme studies have shown strong geographic structuring in Phragmites populations from
different regions of the United States (Pellegrin and Hauber, 1999). However, the genetic markers used in
these studies may not display adequate genetic variation to answer the question of genetic change in the
species. 6
Approach; Recent developments in molecular techniques allow the comparison of large numbers of
samples collected throughout the range of Phragmites australis. Samples from extant populations are being
collected worldwide with a focus on North America and Europe. Data on habitat type, clone age, and other
site specific information are also being collected and will be correlated with genetic data. Historical
specimens from herbaria (e.g., 1004- years old) and preserved rhizomes (500+ years old) obtained from
marsh cores are being used for comparison with modern samples to detect if a change in the genetic structure
of the North American population has occurred. Non-coding regions of the chloroplast genome are being
sequenced and microsatellite markers identified to examine variability in the species. Phylogenetic
relationshipsbetween populations will be inferred using both maximum likelihood and maximum parsimony
techniques. Data will then be analyzed geographically and discrepancies between geographical and
phylogenetic relatedness will be explored further.
SiaiM: Screening of molecular markers is underway and two chloroplast DNA regions have been identified
that show adequate variation for this study. Several microsatellite markers have also been developed and
I am continuing to screen for others.
Papers & Publications; Chambers, R.M., Meyerson, L.A., and Saitonstall, K. 1999. Expansion of
Phragmites australis into tidal wetlands of North America. Aquatic Botany 64(3-4):26 1-274.
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Meyerson, L.A., Saltonstall, K., Windham, L.M., Kiviat, E., and Findlay, S. A comparison ofPkragmites
australis in freshwater and brackish marsh environments in North America. Wetlands Ecology and Manage-
ment (in press)
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U915385
EFFECT OF BIOAVAILABLE METAL CONCENTRATION
ON MECHANISMS OF METAL RESISTANCE
Todd R. Sandrin
The University of Arizona
bioavailable metal and the resulting impact of the activity of these mechanisms
BMionjde.: Over one-thud of hazardous waste sites in the United States are contaminated with both organic
and metal pollutants. The presence of metals at these co-contaminated sites can iiSwodeSSZTof
ssrz^^ bih°remeftion °f these sites ineffective- in »^±ss±
demons^ CLST* t ? **** Sh°Wn tO lnCreaSe With metal ""^ration, but recent studies
demonstrate that higher metal concentrations may be less toxic than lower concentrations Detailed
with toxic cations such as cadm him Th t! u - P "g electrostatic interactions of the cell
oftheabilityo?l±^^
simply by lowerinTthepH of ^^^^
effectofpHonnapS **«" is ^ -d to explore the
containing high levels of zinc anZadm 2 h ^ t f Ca^mium' Lower PH, associated with systems
**"* * '^ '
the presen f low,
(in review)
^
* 8 blodegradatlon of naphthalene. Applied and Environmental Microbiology
«»* of a rhamnolipid biosurfactant on naph-
Andean SoLyforM^^^^
Gener^ Meeting of the American Society for Microbiology.
Chicago, IL, May 29-June 4, 1999
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U915542
PHYSIOLOGICAL STRESS RESPONSES, AGGRESSION AND SOCIAL
DOMINANCE IN WILD WOLVES
Jennifer L. Sands
Montana State University
Objectives/Hypotheses: Todeterminerelationshipsamongsocialdominance,aggression,reproductionand
stress hormone (glucocorticoids) levels in wild wolves (Canis lupus) using non-invasive methods.
Rationale: Chronic elevation of glucocorticoids (GCs) can affect the hypothalamic-pituitary-gonadal axis
at several levels, decreasing the secretion of sex steroids and inhibiting reproduction. Since subordinate
animals in group-living species infrequently reproduce, the conventional hypothesis that social stress is a
cost of subordination seems a reasonable one. But, the fact that elevated glucocorticoids (cortisol, corti-
costerone) levels can compromise reproduction does not mean that this is the normal mechanism by which
social subordinates are reproductively suppressed, as recent studies of free-ranging species have shown.
Advances in endocrine methods now allow noninvasive measurement of GC levels in urine or fecal samples,
which has several advantages for measuring baseline stress hormone levels in the wild. First, the method
itself does not stress the subject animals, and fecal GC levels reflect changes on circulating GC levels over
a period of several hours, rather than a snapshot of GC levels at any given instant. Using these methods,
some field studies have found no relationship between dominance and stress, and others have found that
social stress is a cost of dominance. Determining whether social stress is a cost of dominance or
subordination for wolves pertains to the broad evolutionary questions of how social systems evolve and why
social subordinates tolerate reproductive suppression. Th is research also can be applied towards conservation
and management of this endangered species, by identifying environmental variables that provoke stress
responses. I will examine the effects of capture, translocation and acclimation pens as well as identifying
social, demographic and ecological variables that cause stress.
Approach: Approximately half of the Yellowstone wolf population is radio-collared, making it possible to
locate the wolves on a daily basis. Demographic data, collected by the National Park Service since the
reintroduction in 1995, is available so that age, survival and reproduction are known for all individuals.
Detailed behavioral observations and fecal sampling are focused on three observable packs in the Northern
range of the park. Fecal Sampling: Pack members are observed with a spotting scope. When individuals
defecate the location is recorded and the sample collected once the animal moves away from the area. The
samples are frozen in a 70° C freezer until extraction and assay in our lab at MSU. Behavioral Sampling:
Behavioral observations are made during full-day follows, using all-occurrences sampling. Because
continuous observation is not always possible, the onset and offset of observation periods are recorded and
scan samples at 10-minute intervals are used to correct for biases in observability among individuals. I
record initiator, recipient and class of behavior (winner/loser, where appropriate) for all aggressive,
agonistic, and sexual behaviors. Behaviors other than mating behavior are treated as instantaneous, from
which I will calculate daily rates for each individual, while duration of mating behavior is also recorded.
Sjgtus: I am currently in the middle of my second field season, have collected 270 fecal samples and approx-
imately 300 hours of behavioral observations. This summer, I will complete the cortisol RIAs, measure sex-
steroids for all samples and begin behavioral analysis. For samples from known individuals collected in the
1998-99 breeding season, stress hormone levels were strongly associated with rank (F2,38 = 3.50, P=0.043).
The GC levels of subordinates (739.8 ng/mg dry feces +/-167.5 SE) were only 43% as high as the GC levels
°f dominants (1715.1 ng/mg dry feces +/- 440.7 SE). These data suggest that social stress is a cost of
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dominance in free-living wolves, and is not compatible with the classical hypothesis that reproductive
suppression of subordinates is mediated by chronic stress.
Papers & Publications; None at this time.
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U915154
ENVIRONMENTAL GEOCHEMISTRY OF ARSENIC, SOUTHERN
MOTHER LODE GOLD DISTRICT, CALIFORNIA
Kaye S. Savage
Stanford University
Objectives/Hypotheses: Objectives of this study are to: 1) characterize the sources, speciation and fate of
arsenic in mineralized rocks, weathering products, and associated waters at an open pit mine lake in the
southern Mother Lode Gold District of California. We hypothesize that seasonal variations in arsenic
concentration in pit lake waters are controlled by storm-related washoff of secondary weathering products
that temporarily store arsenic, and by changes in lake water quality parameters related to summer
stratification. 2) quantitatively determine the capacity of the mineral jarosite [KFe3(SO4)2(OH)6] to sequester
arsenic.
Rationale: Because the toxicity of arsenic is related to its chemical form, understanding the controls on
aqueous arsenic speciation in natural systems is critical for assessing its potential health effects and
mitigating its hazards in watershed and storage areas.
AJE,^: Field studies include detailed mapp^^
that form during oxidation of primary sulfide m inerals, as well as seasonal lake water sampling. Techniques
for secondary mineral identification include X-ray diffraction and bulk chemical analyse via d.ges .on/ICP-
MS. High resolution synchrotron x-ray powder diffraction is utilized for identification and charactenzation
of the fine grained and/or poorly crystalline weathering products of pyrite. X-ray absorption spectroscopy
(XAS) indicates the oxidation state and atomic coordination environment of arsenic m the naturally
occurring weathering products and in natural and synthetic model compounds. Comparison with theoretical
modelsenablesdistinctionbetweenadsorptionandsubsti^^^
by secondary minerals. Depths for lake water sampling are chosen based on depth profiles of temperature^
PH, Eh, conductivity and dissolved oxygen determined using a Hydrolab mutiparameter wa er qualrty
monitoring instrument. Filtered (0.45 ^m) subsamples of all waters are "^.^.^ ™™'
alkalinity^™* iron, ArSenic(III) and total inorganic arsenic. As(V) is determined by difference^ Mm-
era. saturation indices in these waters are evaluated using the computer code EQ3/6. A ^^±S
jarosite samples doped with varied concentrations of arsenic are prepared ^ modifymg the procedure of
Baron and Palmer (1996). Solids are chemically analyzed by digestion/ICP-AES and *™*™^
Structural changes induced in the mineral by arsenic doping are assessed by crystal ^^^ -s
synchrotron X-ray diffraction patterns. The atomic environment of arsenic in the synthetic samples is
determined by XAS.
StaiMtMostfielddamcollectionis finished and analytical data have been coHectedfo^
of the samples. Model arsenic-bearing jarosites have been synthesized and spectroscop.cally analyzed.
Geochemical modeling and interpretation of spectroscopic data of natural and synthetic samples are m
progress.
Papers* P. .billions: Savage, K.S, Tingle, T.N, O'Day, PA.. Waychunas G A and Bird, D. K. 2000.
Arsenic speciation in pyrite and secondary weathering phases, Mother Lode Gold District, Tuolumne
County, California. Applied Geochemistry 15(8):1219-44.
Savage, K.S., Bird, O.K., and Ashley, R.A. 2000. Legacy of the California gold rush: environmental geo-
chemistry of arsenic in the Southern Mother Lode Gold District. International Geology Review (in press)
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STAR Graduate Fellowship Conference
A., and Mehta, A. 1999. Characterization of synthetic and natural
80(46):F378. ^^ techniques" EOS' Transactions, American Geophysical Union
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U915580
NATIVE HAWAIIAN CLAIMS AND CLAIMS ABOUT NATIVE HAWAIIANS
Jonathan L. Scheuer
University of California, Santa Cruz
Obiectives/Hvnofheses: In my research, I try to explain the outcome of a water allocation case where
Native Hawaiians were unexpectedly successful by examining how their portrayal may have aftect-
eddecision-makingJalsoexaminetheimplicationsofthissettlementforthefutureofHawaiisenvironment
and other unsettled claims.
Eationaje: The Waiahole Irrigation System was completed in 1 9 1 6 to irrigate sugar on the dry, leeward side
of the island of Oahu. The system's flow comes by capturing water from valleys on the wet »»*"£«*
oftheialand,ana»ahislDric^
Hawaiians and their allies won approximately half of the water from the system in a baflte against some of
the wealthiest and most politically powerful groups in Hawaii. Given the politic.! weakne ^s and poverty
ofthe windward parties, the outcome of the case is an anomaly when , viewed froir >theP.e SP^
theories of public policy. Understanding the outcome of this case is ,mportant to Hawaii s policy makers and
its residents, due to the immense economic, cultural, and environmental value ofthe water.
Additionally, the case is important to others throughout the United States. Resource ^^^
indigenous Americans and federal and state entities are pervasive, expensive and contentiou s_
importance of these claims fights, there is a consensus among scholars and indigenous activis* tha the
claims processes have often been problematic and led to negative social and environmental outcomes. A
better understanding ofthe process resource claim settlement can lead to understanding the divergent and
sometimes negative outcomes.
4fiEroach: Anne Schneider and Helen Ingham's theory ofthe social construction of targe
detailed in their 1993 book "Policy Design for Democracy," states that the social construction
are the targets of policy making is a meaningful explanatory variable in policy studies. They
social construction of target populations as "the cultural characterizations ofthe persons^or grc
behavior and well-being are affected by public policy." They propose that public officials are p
"provide beneficial policy to powerful, positively constructed target populations^'^J^ fa ,
punishment-oriented policy to negative populations." Examining the use oi so
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STAR Graduate Fellowship Conference
U915581
PATTERNS OF TAIL AUTOTOMY IN THREE DIFFERENT POPULATIONS
OF A NEOTROPICAL LIZARD, NOROPS POLYLEPIS
Martin A. Schlaepfer
Cornell University
Objectives/Hypotheses; To test whether rates of tail autotomy differ between different populations of the
common anole, Norops polylepis, within the area of Las Cruces, Costa Rica.
Rationale: Although potentially life-saving, tail autotomy (loss) also has important costs on future survival
and perhaps even reproduction. Different rates oftail autotomy between populations or sexes probably reflect
different ecological situations (e.g., differences in predation pressure, intraspecific competition) and thus,
different selective pressures that may lead populations down distinct evolutionary pathways.
Approach; I sampled 864 individuals of the common anole, Norops polylepis, from three distinct
populations near Las Cruces, Costa Rica, and recorded occurrence of tail loss (autotomy). I tested whether
rate of tail autotomy differed between sexes, age-classes, and populations.
Status: This mini side-project, conceived and carried out for purely academic reasons, and totally unrelated
to my EPA-STAR proposal, is now complete.
Papers & Publications; Schlaepfer, M.A. and Figeroa-Sandi, R. 1998. Female reciprocal calling in a
Costa Rican leaf-litter frog, Eleutherodactyluspodiciferus. Copeia 1998:1076-80.
Schlaepfer, M.A. and Gavin, T.A. Edge effects on lizards (Norops) and frogs (Eleutherodactylus) in tropical
forest fragments. Cons Bio (in press)
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TJ9 15540
A COMPARISON OF DECOMPOSITION IN RESTORED AND NATURAL NON-TIDAL
FORESTED WETLANDS IN EASTERN VIRGINIA
J. Michael Schmidt
Virginia Polytechnic Institute and State University
Objectives/Hynotheses: To compare the rates and organisms that mediate decomposition in restored and
natural forested wetlands along a moisture and time gradient.
Sationale: With increased understanding of the ecological importance of
government's "no net loss" wetlands policy, maintaining ^^^^
increasingly socially and economically important. While decomposition is
attributesofwetlandsjtisnotwellunde^^
variable depending on the type of wetland. Litter decomposition "^^^*£S^u*ty.
fromuplandandaqUcstudies^^^
Given the variability in soils, salinity, vegetation, hydrology, climate and water sourc p variability
only been determined in relatively few wetland types. In an attempt <°^^^f
in decomposition rates, several other factors such as age since restorafcon, mo.sture levels, U
size, and litter type will be examined.
: This project studies constructed and natural 'reference'
a water budget and a decomposition study. The created wetlands \o
Apartment of Transportation to replace wetlands destroyed by ^^^ £ h7lO year-old
* 2 year-old wetland are being studied. The water budget will ^^^^^f^^^fa^
-etlandbyestimatingthebsses^^^^
jvaterflow.andprecipitationwillbemeasuredorest^ p d Iate the
be estimated through both cloth burial strip and *^!^^%%££* decomposition.
greasing tensile strength of a strip of unbleached cotton fabric to ^^^^wtom***.
Litterbags have been used extensively to study decomposition in both t™™^ then a few bags m
Typically, a large number of mesh bags are filled with plant Utter, placed m an -ea,andjhe ^
Periodically removed to determine of weight loss and mmera ' ^^^'^ ^ eymergent marsh
types of litter will be used: the hardwood leaves common m he ^^^^ sources, ^ mesh
vegetation. In order to estimate the proportion of *"™%£^^
sues will be used. A fine mesh will estimate ^^^^S^^^- The arthr°Pod and
a coarse mesh (2-4 mm) will allow access to all but the largest mac ible for the iitter
•nvertebrate communities will be surveyed to determine , whu* ^J^^lxjtw€CIirestored
breakdown. The main comparison will be ^^^^^^B a temporal and moisture
^d natural wetlands. Secondary comparisons ^n^^
gradientinthe created wetlands. This ^"7*^^^ ,oi, development studies conducted by
can be correlated with the water «f *>:"
Previous researchers. Site selection for htterbag pJacemem wi
correlations and connections to be made.
first of several burial strip studies will be placed in
ife wVto^urta^r;;;^: m »<*« win be .«,*»< by»«, „»»
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Papers & Publications; None at this time.
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STAR Graduate Fellowship Conference
U915575
FLOODPLAIN MANAGEMENT AND ECOSYSTEM FUNCTION ON THE STANISLAUS
RIVER: AN EVALUATION OF HYDROLOGIC AND FLUVIAL
GEOMORPHOLOGIC ALTERATION
Katrina S. Schneider
University of California, Berkeley
Objectives/Hypotheses: Examine the degree to which flood and water management procedures have
impacted ecosystem function along the Stanislaus River. In particular, I will focus on changes over the last
century in the hydrologic regime (flow magnitude, duration, frequency and timing) and river morphology
(access to and inundation of floodplains; connectivity of floodplain and river channel) in the lower Stanislaus
River.
Rationale: Traditional floodplain management strategies of reducing flood discharge through reservoir
storage and isolating floodplains from river channels with levees have been implemented on a large scale
in the Stanislaus River, the northernmost large tributary in the San JoaquinRiver basin. Stanislaus fall-run
Chinook salmon populations have declined from 35,000 spawning fish m 1953 to less than 300 in 1991 and
1992 (Calfed 1999) The decline in fall-run populations has been linked to the loss of key ecological
processes, such as high river flows, river meandering and channel diversity, and the recruitoent of coarse
sediment supply to the active channel. The Stanislaus basin is regulated by over 40 dam ^ which
cumulatively Impound the equivalent of 240% of average annual unimpaired basm ™^ NewMriones
Reservoir, the largest reservoir in the San Joaquin river system, contains 85% of the basinforage and
effectively prevent flooding. As a result, winter flows from basm reservoirs are but at smaU jracUon of
historical floods, while summer releases are higher to supply irngat,on demand. These hydrology^changes
have had additional consequences for adjacent riparian habitats as the frequency and pattern_of floodp am
inundation has been dramatically altered. The functional isolation of these floodplain ~^ ^ ™*
channelhas resulted in the loss of important terrestrial-aquatic habitat and has been listed "P^tocaro
for native species decline. I will assess changes in the hydrologic regime and geomorphoogi^^processes
resulting from floodplain management and irrigation storage activities, and characterize the impacts on
ecological processes for riverine species.
Abroach: I will begin with a literature review of the role of natural river processes in ^ heaW^
^S£ffi»-^tS^
flow magnitude frequency, duration and timing for pre- and post-dam periods. I will also examine human
occupation of the floodplat, for residential development and agricultural use and <^« * «JT^
to dam and levee construction. Secondly, I will examine changes m geomorphologic features of the river
channel and its broader floodplain using historical aerial photographs and re-occupafon of historical survey
sites to document changes in channel morphology, vegetative cover, and other features. Using steady-flow
hydraulic models I will assess changes in floodplain inundation and connectivity due to the presence of
dams and levees Finally I will explore the biological implication of these changes drawing upon research
on the Cosumnes River preserve and the Yolo Bypass, especially with respect to life cycles offish such as
Juvenile salmon and splittail.
s: I am currently using the IHA flow model to assess hydrologic alteration on flow data back to 1913.
acquire aerial photographs dating to 1937 by the end of the semester, and identify locations of extreme
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alteration from development, vegetation encroachment, and loss of floodplain inundation and connectivity.
I w.ll collect survey data to evaluate geomorphologic changes and floodplain bores to assess depositional
timing at various study sites this summer.
Papers & Publications; None at this time.
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U915363
WATER AND NUTRIENT FLUXES FROM SUBMARINE GROUNDWATER
DISCHARGE IN THE DELAWARE ESTUARY
Matthew C. Schwartz
University of Delaware
Qbiectivcs/HvpnfhP^ I am working to quantify the amount of groundwater that enters the Delaware Bay
Estuary via submarine groundwater discharge (SGD) in order to determine the biogeochemical impact of
SGD nutrient and contaminant fluxes. Furthermore, I seek to determine the seasonal and mterannual
variations in the water and nutrient fluxes associated with SGD in the Delaware. The methods developed
and results obtained, during the course of this study can then be used to determine whether SGD water and
nutrient fluxes are significant variables in hydrogeological and biogeochemical studies of other coastal and
estuarine environments.
Bationaje: The exchange of groundwater between terrestrial aquifers and surface waters via SGD may be
a significant source of nutrients and/or contaminants to the estuarine and coastal ocean receiving waters.
Groundwater in aquifers on the Delmarva peninsula have high nitrate concentrations due to the application
of fertilizers to the overlying agricultural lands. Groundwater quality is affected on an international scale
through both industrial and agricultural activities on the land surface and in *e subsurface. SGD occur
anywhere that an aquifer is hydraulically connected with the sea" (Johannes 1980); therefore, SGD holds
the potential to impact estuarine and coastal waters throughout the world by transporting anthropo-
genically-impacted groundwater to the coastal zone.
^BBroach: I have collected a series of water column samples for natural radioisotope analysis Sp^ifeally,
I measured the radon and radium activities in surface waters in order to identify areas of Excess Rn (Rn/Ra
activity ratio > 1 .0) that may be associated with groundwater exchange from nearby aquifers, wh^ ^h con* n
radon-enriched groundwater. I have also collected and analyzed severa sedunent cores ^ ««^
used for two pulses: to determine the apparent diffusive input of radon to the ^^"£%£
sediment-watLLrfaceandto survey sedimentsandporewaterfortheadvective^
'olumn. These data were then incorporated in an advection-^^
with a colleague. I used this model to determine the apparent groundwater ««v«*toante to my shriyait*
a 12 km long by 2 km wide section of the Delaware Estuary From the ff™0^!^^^
Aquifer geochemistry, I then calculated the amount of nitrate that may be entering the Estuary via SGD.
rounds of water column data and-sediment cores have been collected at this point. I have
^
a.panto
the se^JShSSSto my study site. I also plan to more fully characterize^ the diffusive input of
radon to the wlr clmn via collection and analysis of additional sediment cores. These efforts wi 1 allow
"* to more fo£ ? constmin the current advection-diffusion model in order to more accurately calculate the
groundwater flux and associated nutrient fluxes to the estuarine receiving waters. I plan to complete this
research by summer 2001.
: Schwartz, M.C. Significant groundwater input to a coastal plain estuary: assess-
ment from excess rn. (in preparation)
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U915432
CNIDARIAN-ALGAL SYMBIOSIS: EXPRESSION AND SYNTHESIS
OF A SYMBIOSIS PROTEIN, SYM32, IN TWO CNIDARIANS
Jodi A. Schwarz
Oregon State University
Objectives/Hypotheses; My objectives are to investigate how coral-algal symbiosis is initially established
at the orgamsmal level and how it is regulated at the molecular level by examining how the partners come
together physically, and how expression of one symbiosis-specific gene (sym32) changes during onset of
symbiosis and during periods of environmental stress.
Rat.io"a'e: Cora]-ajgal symbiosis forms the foundation of coral reef ecosystems. The recognition that the
health of coral reefs is declining globally underscores our fundamental lack of knowledge about how the
symbiosis is established, regulated, and maintained at the molecular level. This research seeks to understand
how the partners in the symbiosis come together and how the symbiosis is established and regulated at a
molecular level. &
: To address questions about how a healthy symbiosis is established and regulated and how
LIT7 Pf*0**1™ »™jt in a b««kdown of the symbiosis, I am examining the problem at two
levels, the orgamsmal level and the molecular level.
u is in host species who are initially
h°W,theSe h°StS ac^ their *« complement of symbionts from the
, deVelTem' ^ m btroduced to ^xanthellae from different
» t * " ^^^ ObJective 2= At the molecular level, I am examining the role
, a protem that ,s significantly upregulted when hosts contain symbiotic algae and thought to be
cells, the sym32 gene begins to be expressed after the onset of symbiosis in larvae Using
immunocrt
chaT/esl^
changes throughout development. To determine the effects of environmental stress adult hosts will be
11S^^^^
a bleaching), and levels of svm32 w.ll be monitored using either Western or Northern blots.
latus: The sym32 gene has now been identified in four cnidarian that are symbiotic with algae In A.
^
oc w agae .
ed
ed
development ahho ,7" T f ^^ ** ^^ Sym32 mRNA is Pr very early in
aene I ^±7 e8gSn Sym32 mRNA' ] day °ld embryos aPPear to be transcribing fte sym32
farTae acTuire T? "i'1"8 Qu&ntltf ^ ?CR tO detemiine Whether ^ *>*& gene is uPre|ulated after
IndodeZl and I8 1 H Imn!UnoCytohf ochemis^ ^ demonstrated that sym32 is upregulated in both
endodermal and ectodermal tissues of hosts that contain symbiotic algae. I am currently proceeding with
the electron microscope level to
onse
^ SCIhwar2'J-A"KruPP'D-A^ndWeis)V.M. 1999. Late larval development and
y the scleractiman coral, Fmgia scutaria. BiolBull 196:70-79.
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Reynolds, W.S., Schwarz, J.A., and Weis, V.M. 2000. Symbiosis-enhanced gene expression in
cnidarian-algal associations: cloning and characterization of a cDNA, sym32, encoding a possible cell
adhesion protein. Comp Biochem Physiol A (in press).
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F9F10676
PREDICTIVE SOIL MODELING IN SOIL SURVEY
Peter R. Scull
San Diego State University
Objectives/Hypotheses; To integrate GIS and Remote Sensing technology into standard soil survey in or-
der to make large-scale soil mapping more cost effective, and to produce more robust data products.
Rationale; Knowledge of the soil resource is critical for land management decisions in the Mojave Desert,
yet the region has never been fully mapped. Soil maps were considered low priority until concerns regarding
management of the delicate desert ecosystems and their biodiversity became important. The majority of the
Mojave Desert is managed by government agencies. The National Park Service and Department of Defense
have contracted soil mapping to the National Resource Conservation Service (NRCS), but Bureau of Land
Management (BLM) has not yet mapped the soil resources under their jurisdiction. If the NRCS can
convince BLM that these data can be gathered at reasonable cost, a sound basis for ecological management
of the Mojave could become a reality. The overall goal of the research is to facilitate this by increasing the
efficiency of soil survey.
Approach; Decision tree analysis (DTA) is a model framework that can be used to create predictive models
of soil occurrence. DTA was selected because of its capability to integrating a wide range of data sets
(remote sensing and DEM products, as well as a variety of ancillary data) and because it makes intuitive
sense, allowing easy communication with soil experts. DTA involves successively partitioning the depen-
dant variable into increasingly homogeneous subsets. Splits, or rules defining how to partition the data, are
selected based on information statistics that define how well the split decreases impurity within the data set.
Once the tree has been constructed (or grown), it has encoded a set of decision rules that describe the data
partitioning process. These rules can be applied to a geographic database to predict the value of a response
variable in an area where the predictor variables are known, but the response variable is not Binary decision
tree models have been developed in areas previously mapped and will be applied in similar areas that have
not yet been mapped. This method can be used to provide the soil mapper with a set of maps characterizing
the probability of mapping unit occurrence in an unmapped area.
Status: We have tested the method on existing data and it has shown to be effective in a pilot study area
within Fort Irwin Military Base. Fort Irwin will be expanding south and would like to map the soils of the
expansion area. Predictive models will be used to produce a preliminary soil map to aid in the survey
process.
Papers & Publications; Merkler, D.J., Lato, L., and Scull, P. 1999. A soil survey of Death Valley Na-
tional Park-new techniques in standard soil survey. Slate, J.H., ed. U.S. Geological Survey Open-File
Report 99-153, pp.111-13.
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U915394
AN ASSESSMENT OF FAMILIES' EXPOSURES TO, AND THE RELATIONSHIPS BETWEEN,
PERSONAL, INDOOR, AND OUTDOOR AIR CONCENTRATIONS OF FINE PARTICLES
AND AIR TOXICS: RIOPA, LOS ANGELES COUNTY, CA SITE
Derek G. Shendell
University of California, Los Angeles
Objectives/Hypotheses; One of the main goals of the RIOPA ("Relationship Among Indoor, Outdoor, and
Personal Air Concentrations") study is to investigate the correlation between outdoor, indoor (home,
in-vehicle, school office), and personal exposures to fine particulate matter (PM2 5) and toxic air compounds
from various biological and anthropogenic sources. RIOPA is the comprehensive exposure assessment of
householdsacross microenvironments and times of day (time-activity patterns), sources (natural and human),
and natural variability (meteorology and topography).
Rationale: The national multicenter RIOPA study (Elizabeth, NJ; Houston, TX; and Los Angeles County,
CA) seeks to help establish a scientific foundation for effective, timely public health enhancing intervention
strategies (i.e., risk management).
Afiprpach: Outdoor, indoor, and personal exposures of adults and children ages 8-18 are measured then
evaluated by mass, elemental, chemical, and source apportionment analyses. Modified Harvard impacter
samplers (PM2 5 and elemental analysis for metals) and MSP sampling heads (PM2.5 and organic vapors) will
be used to characterize the interdependency of absolute levels and variations in outdoor and indoor
microenvironment PM25 concentrations. Carbonyl and volatile organic comP°""ds Wlll^e mjesSJJS
concurrently with active and passive samplers (e.g., 3M OVM 3500 badges, DNPH cartridges, DNSH
badges). Time-activity patterns will be assessed from subjects' diaries; standard instructions ^^'
oped. Two groups of non-smoking asthmatic and non-asthmatic adults and their ch.ldren selected by
random probability sampling in each of four communities [West Los Angeles, NewhalWdewia CiMwa
Clarita), Pico Rivera, Burbank], will be included. All participating subjects me five eligibility criteria
including designation to the case or control group. Cases were households who lived wittan 0.5 tan of^a
major freeway (e.g., interstate, state route) or intersection of two or more freeways. Control were
qualitatively similar to cases (e.g., by housing stock) in all respects, but lived more than 0.5 km away from
amajorfreewayorintersection.Monitoringwil^
to capture higher ventilation (spring, summer, and fall in CA) and lower ventilation (winter in CA) seasons^
Results will be compared across microenvironments, seasons, and communities as well as between case and
control groups within or between cities.
Status: As of April 14,2000, in West Los Angeles 12 of 34 eligible (out of 80) randomly selected subjects
(36.4% participation rate, 27.3% with 10 subjects who could not be contacted for eligibility), and all 8
eHgible(ofabout50)non-randomSubjects, participated. Eighteen of 19 homes^ne became ineligible-were
monitored a second time. In Santa Clarita, as of April 14, 2000, 12 of 27 eligible (out of 50) randomly
selected subjects (44.4% participation rate, 38.7% with four subjects who could not be contacted for
eligibility), and one eligible non-random subject, participated.
Papers & Publications; Shendell, D.G. Promotion of renewable energy sources (at local level) through
Public-private partnership initiatives, http://www.undp.org/ppp/ [Global Learning Center -> Research Clinic
1998 -> Summaries]
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Shendell, D.G., Naeher, L.P., Smith, K.R., and Boy, E. A rapid exposure assessment protocol for PM2 5 and
CO concentrations and PM2 5 source apportionment in smaller developing-country cities with limited
resources: case study in Guatemal a. Wrote abstract for and presented poster at The Role of Human Exposure
Assessment in the Prevention of Environmental Disease, a NIEHS workshop, September 22-24, 1999,
Rockville, MD.
Shendell, D.G., Naeher, L.P., and Boy, E. Ground-level PM2 3, CO, and trace element concentrations in
Guatemala, (in preparation to submit to Atmospheric Environment or Environment International, Spring-
Summer 2000)
Shendell, D.G., Winer, A.M., and Colome, S.D. Assessment of organic compound exposures and HVAC
functioning in public school portable classrooms in Los Angeles County, CA. Wrote abstracts for and
presented posters at the University of California Toxic Substances Research and Training Program Annual
Conference, April 27-28, 2000, San Diego, CA, and the Southern California Society for Risk Analysis
Annual Conference, May 18,2000, Los Angeles, CA.
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U915562
MECHANISTIC STUDIES OF VITAMIN B12 MEDIATED DECHLORINATION
Justin Shey
University of Illinois, Urbana-Champaign
Objectives/Hypotheses; To elucidate the chemical mechanism by which certain enzymatic and non-
enzymatic systems dechlorinate perchloroethylene (PCE) and trichloroethylene (TCE).
Bationaie, PCE and TCE are ubiquitous and persistent pollutants that are believed to be carcinogenic.
Anaerobic bacteria and cultures have been discovered at contaminated sites that dechlorinate PCE to TCE
and subsequently to cis-dichloroethylene (DCE). Purification of the enzyme system responsible .for the
dechlorination of PCE has shown the involvement of iron-sulfur clusters and a cobalam n The de-
chlorination of PCE by non-enzymatic means has also been carried out utilizing titamum(III citra e to
"Kiucccyanocobal^
are not known, but several possibilities have been postulated. If the mechanism and rate ^'J^^ms
dechlorination can be elucidated for the abiotic system, rational design and synthesis of remediation systems
that are inexpensive and more effective could be realized.
Abroach: To understand the mechanism of non-enzymatic dechlorination I have ff^^%££
the dechlorination of two radical probes (cis and trans-(2-trichlorovmyl^ fols aloha
*«oppc*flowUV-visap^
to the cyclopropane ring during the dechlorination process. If the major products -» ^°P"cM ^
support a mechanism in which radicals are involved in the non-enzymatic <^'"
2-propanol is a good hydrogen atom donor, the dechlorination of the tons
Performed in deuterated water with 2-propan(ol-d) as well as water ^
water system provided more deuterated products, it would suggest that the V
aproton. Likewise, if the water system resulted in more deuterated products,
thattheproductobtainsthehydro^^
°f the oxidation states of cobalt on the sub-second time scale. Since *
cobalt in cobalamin offer very distinct UV-vis spectra, the mechanism
by observing the cobalamin during the reaction. With the stopped-flow
these reactions could also be obtained.
Status: The products from the dech.orination of the two radical j^^
suggest initial electron transfer to the chlorinated ethene followed by Mo
"hydrogen atom incorporation. Continued use of the stopped-flow apparatus is planned, atter
investigate the details of an enzymatic dechlorination reaction.
SaBgrs & Publications: None at this time.
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U915412
DEVELOPMENT OF A SUSTAINABLE MANAGEMENT FRAMEWORK
FOR THE UNIVERSITY OF MICHIGAN HOUSING DIVISION
Michael P. Shriberg
University of Michigan
Objectives/Hypotheses! To provide a framework upon which to base management for ecological sustain-
ability in the University of Michigan's Housing Division (Housing).
Rationale; Educational institutions are an integral part of society, not, as some may envision, an "ivory
tower." The environmental burdens of an organization that provides housing to over 9,000 students, man-
ages over 4.2 million square feet, and employs over 3,700 people are vast. However, until recently,
environmental management within Housing has been conducted in a piecemeal fashion. This study helps
move Housing toward a coordinated, anticipatory, and upstream approach to environmental management,
through the framework of sustainability. This framework will be useful for other organizations interested
in management for sustainability.
Approach: The study presents mechanisms for organizational alignment with sustainability by assessing
leading edge sustainablepractices and their applicability, describing Housing's current environmental status,
suggesting sustainability visions, recommending initiatives to move Housing toward sustainability, and
proposing indicators to measure progress.
Status; Will be completed by August 2000.
Papers & Publications; Sustainability management in campus housing: a case study at the University of
Michigan. The International Journal of Sustainability in Higher Education (in press)
A housing challenge at the University of Michigan. The Declaration: Association of University Leaders for
a Sustainable Future 2000; 3(3):4-7.
Shriberg M Assessing management for sustainability in the University of Michigan housing division:
phase I. The Talking Stick 1999; 17(3): 13-16.
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U915354
SOURCE CHARACTERIZATION AND APPORTIONMENT OF AIRBORNE
PARTICLES USING MASS SPECTROMETRY
Philip J. Silva
University of California, Riverside
Objectives/Hypotheses: To perform the first comprehensive study of airborne particles emitted by primary
sources with a single particle mass spectrometry technique and use the emissions data for source appor-
tionment of ambient particles.
Rationale: Using a single particle technique, we believe that we can identify and trace different particle
types arising from different sources in the atmosphere. This can be done by using distinct chemical markers
on the individual particle level acquired using mass spectrometry. We believe that using this single particle
method will be more precise than attempting to deconvolve different sources of aerosol using a chemical
mass balance of bulk chemical analysis data. It will also allow for tracing with much better time resolution
then methods that rely on bulk analysis.
Abroach: Aerosol time-of-flight mass spectrometry (ATOFMS) is a single particle ^'' **^"
with real-time capabilities. ATOFMS yields data on both the chemical composition (using mass spec ro-
metry) and the size (using aerodynamic sizing) of individual particles. By obtiuning a size and cherr ucal
composition for each individual particle, it is possible to obtain a unique "fingerprint for chfferer type £
particles. These fingerprints can be obtained for different particle sources during emissions t^Once
obtained, the particle fingerprint can be used to identify particles based on their source m ambient samples.
Status: All source characterization and ambient experiments have been completed. Publications describing
the work are currently being written up.
.-: Silva, PJ. and Prate, K.A. ******* °< '«• s
in aerosol thne-of-flight mass spectrometry. An,lyt,cal Chem.stry (su
SMva, P.,., carlin, R.A, and Prather, K.A. Single pardc.e analysis of suspended soil dust from southern
California. Atmospheric Environment 2000;34; 1811 -20.
Gross, D.S, Galli, M.E, Silva, PJ, and Prather, K.A. Relative -sitior for
ammonium ions in single-particle aerosol time-of-flight mass spectrometry.
72:416-22.
, P.,, Liu, D.V., NoWe, C.A., a,* Prather, *£
Particles resulting from biomass burning of local southern
Technology 1999;33:3068-76.
SHva, P., and Pratner, K.A. On-line chara^zationonndiv^a, particles resulting from automobile
emissions. Environmental Science and Technology 1997;31:JU/4-»u.
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U915596
WATER USE AND ROOT FUNCTION OF TREE SPECIES
IN SEMI-ARID RIPARIAN ECOSYSTEMS
Keirith A. Snyder
University of Arizona
Objectives/Hypotheses: The main goals of this research are to understand the environmental and
physiological controls on water use and root allocation behavior of riparian tree species. This research is
designed to answer the following question: why do some populations and species use shallow surface
moisture while others do not?
Rationale; In semi-arid and arid regions, groundwater pumping and surface water diversions have severely
altered the composition and function of riparian ecosystems. Understanding the link between hydrology and
vegetation is crucial to our understanding of the global water cycle and necessary for accurate modeling of
watershed processes. In addition, understanding the effects of declining groundwater tables and changes in
regional precipitation patterns on the behavior of riparian tree populations is of great concern because arid
land riparian areas support a unique assemblage of forested vegetation. A detailed understanding of how tree
species respond to water availability is important to the management and restoration of these systems, and
for predicting terrestrial plant responses to global climate change.
Appr°ach: These 8°ais were ^dressed using a combination of field studies, field experiments and
greenhouse experiments. Physiological explanations for the tremendous intra- and inter-specific variation
observed for water source use by trees in riparian may be partially explained by unique species responses
to temporal and spatial heterogeneity of water sources in the plant's rooting zone. I predicted that in habitats
where groundwater is deep, riparian trees preferentially will use water from growing season precipitation,
slLPTSotont mT H f 8TdWater °r Perennial Stream ™r would not use precipitation.
Stable so-top c methodology was used to determine the sources) of water for cottonwool (Popito*
f^=^^^
ofth^^
^.^±!!Z ^ *??* ^^ ^ ™»' Water sources used by riparian trees
varies among stream typesonthe San Pedro River, Arizona. Agricultural and Forest Meteorology (in press)
°^ 1998'
' ^ersourcedeterminationincottonwood/willow
rologlcal Society, Spec^^^
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U915S5
EFFECTS OF SOIL/SEDIMENT ORGANIC MATTER ON THE DESORPTION,
BIOAVAILABILITY, SEQUESTRATION, AND TRANSFORMATION OF PHENANTHRENE
Sara B. Soderstrom
University of Michigan
Objectives/Hypotheses: To determine the effects of soil/sediment organic matter (SOM) on the desorption,
bioavailability, sequestration, and transformation of phenanthrene.
Rationale: Sorption, bioavailability, and sequestration are interrelated phenomena affecting the transport
and ultimate environmental fate of organic contaminants in subsurface systems. An important condition that
influences these phenomena is the physicochemical character of the sorbent. Previous studies in our abor-
atories have shown that SOM can be modeled by two separate domains. Older soils ^and sediments Aat have
undergonesignificantdiageneticalteration^^^
condensed and chemically reduced. These soils exhibit more nonlinear, slower, and only partially reversible
sorption of hydrophobic organic compounds (HOCs). Conversely, younger soils that have ""l"^"™
or no diagenetic alteration have "soft-carbon" dominated SOMs that are more phys.caUy amorphous and
chemically oxidized, and typically exhibit nearly linear, faster, and reversible HOC sorptiorL The
bioavailabilityofacontaminantreferstotheabilityofabiotic species to access ^con^m™\'A<™™"
measure of bioavailability is the microbial mineralization profile. A standard assumpt.on is that &8PAdK"
occurs in the aqueous phase only; therefore, desorption is expected to p ay a key role ,n bioava,la hty.
Thus, it can be hypothesized that analysis of SOM, which affects desorption, could be used to pred.ct the
bioavailability of contaminants.
: Three geosorbents were characterized using "C-NMR to determine the ^f^
rbon. Mfchigan Peat is a relatively young soil from which phenanthrene readO> ' d ^
il is a high organic, muck-type top soil with an intermediate hysteresis index; Lachme Shale is
logically old soil with a high hysteresis index. The sorption isotherms were
Soils were aged under anoxic conditions for 2 and 4 months. The mass °
was variedto achieve a constant equilibrium aqueous concentration. Radiola ^j
was added to each bottle as a tracer. The bioflasks consisted of a 250 ml flask with
Mroxide and a side arm. A concentrated mineral nutrient solution and a cell
CRE7, a phenanthrene degrader, were added to the flasks. The NaOH was «£
* sampling to measure the extent of mineralization. Oxygen was added ^through , the
aerobic conditions. Measurements of the desorption rate were conducted
desorption method with TenaxTA polymer. After mineralization, both comb
were used to recover 14C-organics from the geosorbents.
analyze the reactivity of phenanthrene metabolites with the SOM. The experiment w
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a wider range of geosorbents in order to develop quantitative methods to quickly predict the feasibility of
bioremediation at a contaminated site.
Papers <& Publications; None at this time.
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U915530
SOURCES OF NUTRIENT INPUT IN AN URBANIZING OREGON WATERSHED
Kazuhiro Sonoda
Portland State University
stream water quality.
In addition to natural weathering process, streams n
from various landuses that surround them.
difficult to identify. Johnson Creek, a 140 km' wz
culturally-based rural area and terminates in an urbanized:
form both rural and urbanizing areas. Preliminary'findings ^—r^^iVhighly populated area
Creeksuggestsignificantincreaseso^^
of the Johnson Creek watershed. Because there are no identified ooint sources
urbanization on surface water quality deserve a comprehensive study.
^^^^^
A mass balance c rt IF wnn 1
Hydrologic parameters, including storm n
runoff contribution to dry wells, will be • ^ored and ™£™££%^ contributiL of precipi-
and dry season. Oxygen isotopes ratio 08O/16O>™ " b^ ^'Dr^enSive study should provide a complete
tation, soil water, and groundwater to SSSSii. urbanized watershed. Results
j * i • rpnUueeest that uroanization, such as an increase in housing
Our recent findings (Sonoda etai.m prep.; & &B 'ncrease in phosphorus (P) concentration in
-.., and industrialization, ^*^«££^ closely relates to rural landuse. Correlation of
treamwater, while NO, +NO2- nitrogen (N) concentrat on ci y icultural practices within the rural
N concentrations to rural landuse can be explained oywio y F ef is being investigated by this
area. The correlation between P concentrations and urbanization,
study.
rF andYeakley J A 1999. Correlations between landuse
gapers & Publications: Sonoda, K., Walker, u.n., an '' ^ Watershed Management to Protect
andnutrientinPutstoanurbanizingOregonstream.In:J>.^tunev , - Resources Conference
r-» i- . . . « AX7atf»r Resources ASSOClallUll rvunwu
Declining Species: American Water Rewuiw^
Proceedings, Seattle, WA, December 5-9,1999:441-44 .
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U915564
ACCUMULATION OF ATMOSPHERIC AND SEDIMENTARY PCBS
IN A LAKE MICHIGAN FOOD WEB
Heather M. Stapleton
University of Maryland Center for Environmental Science
Objectives/Hypotheses; The Great Lakes region is an area well known for PCB contamination, especially
as evidenced by the elevated concentrations found within apex predators, such as lake trout and salmon that
are commercially and recreation ally important. Since the curtailment on PCB use in the 1970s, concen-
trations have shown a relative decrease in the environment. However, in the late 1980s, a stabilization in
PCB concentrations, just above the FDA advisory level (2 micrograms/g) was observed in Great Lakes lake
trout, and appear to be remaining steady (Borgmann& Whittle, 1991; Miller et ah, 1992; Stow etal., 1995;
DeVault et al., 1996). The reason forthis stabilization is unclear, but plausible hypotheses include large-scale
atmospheric exchange (Baker and Eisenreich, 1990), internal recycling of historically contaminated sedi-
ments (Lester & Mclntosh, 1994), and alterations in food web dynamics (Rasmussen et al 1990) The intent
of this current investigation is to assess the relative influence of atmospheric exchange,'internal recycling
within the water column and sediment, and food web dynamics on PCB assimilation within the fisheries of
Lake Michigan.
Rationale: (Not received at time of printing.)
AfiErpacJi: Field work began on this project in April 1997 and was completed in September 1999. A
temporal sampling strategy was designed to collect samples from the air, water, sediment, and representative
biota in order to assess the impact of seasonal dynamics on PCB burdens within abiotic and biotic
compartments, and to determine the primary route by which PCBs are currently being supplied to the
fisheries. Representative food web members include: buld plankton, benthic amphipods (Diporeia hoyf),
oppossum shrimp (Mysis relictd), deepwater sculpin (Myoxocephalus thompsoni), alewife (Alsoa
psevdoharegnus) bloater chub (Coregonus hoyi), rainbow smelt (Qanerta mordex), lake trout (Salvelius
namaycush), burbot (Lota lota\ and salmon (Oncorhynchus sp.). Isotopic signatures of food web members
have been analyzed to determine their trophic status as estimated by the nitrogen and carbon isotope values,
and in addition, diet analyses have been conducted on fish species to determine their major prey items.
These parameters will a,d in establishing a trophic model of the food web and be useful in determining the
dynamics of PCB transfer through bioaccumulation.
Status; (Not received at time of printing.)
Papers & Publication.,; Stapleton, H.M., Baker, J.E., Ostrom, P., Masterson, C., and Skubinna, J. 2000.
Correlatmg del 13 carbon and del 15 nitrogen with PCB and toxaphene bioaccumulation among members
of a Lake Michigan food web: investigating pelagic and benthic contaminant pathways, (draft manuscript)
Stapleton, H.M., Baker, I.E., Skubinna, J., and Masterson, C. 2000. Seasonal dynamics in PCB and toxa-
phene bioaccumulation in a Lake Michigan food web. (draft manuscript)
Stapleton H.M Cohen, A.R., Cornwell, J., Jeremiason, J.D., and Baker, I.E. 1999. Loadings of PAHs,
a* P, ? m T? C,°reS C°lleCted fr°m °rand TraVCrSe Bay>Lake ***&"• Presented at
annual conference of the International Association of Great Lakes Research in Cleveland OH
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Stapleton, H.M, Jeremiason, J.D, Ostrom, N.E, and Baker, J.E 1999. Organoch.orine b^» £^
web of Grand Traverse Bay, Lake Michigan. Presented at the 42nd annual confernce of the International
Association for Great Lakes Research in Cleveland, OH.
Stapleton,H.M,JeremiaSon,J.D,andBakea
of Grand Traverse Bay, Lake Michigan: investigating current sources. Presented at the SETAC 19th annual
meeting in Charlotte, NC.
ct n A Baker j £ 1998 PCB accumulation in the food web of Grand
ttapleton, H.M., Jeremiason, J.U., ana^ cu^entsources presented at the 41st annual IAGLR conference
in Hamilton, Ontario.
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U915625
THE EFFECT OF ELEVATED CO2 CONCENTRATIONS AND VEGETATION
MORTALITY ON MINERAL WEATHERING IN SOILS
Jennie C. Stephens
California Institute of Technology
Objectives/Hypotheses: The primary goal of this research is to determine the response of mineral
weathering to both elevated soil CO2 concentrations and varying organic acid concentrations in soils from
Mammoth Mountain, California.
Rationale; Weathering of Ca and Mg silicate minerals is the primary sink for atmospheric CO2 over geo-
logical time. Atmospheric CO2 concentrations are currently rapidly increasing primarily due to the burning
of fossil fuels. Attempts to predict global climate change due to increasing atmospheric CO2 require a
thorough understanding of the processes involved in all sources and sinks within the geochemical carbon
cycle. This includes identifying and understanding the mechanisms and kinetics of all factors that may affect
the weathering of silicate minerals, either by enhancing or inhibiting mineral dissolution One important
factor that is currently not well understood is the role of CO2 itself. Whether or not CO2 has a direct effect
on mineral weathering rates is unclear. Another important factor, which has been studied in the laboratory
extensively, is the effect of low molecular weight organic acids. It is well established that some low
molecuar weight organic acids accelerate silicate mineral dissolution. In soils, organic acids are produced
primarily from the roots of viable trees. On the flanks of Mammoth Mountain, California, extremely high
concentrations of soil CO2 from a magmatic source have been killing the vegetation This site provides a
unique opportunity to examine how mineral weathering in soils responds to high CO2 concentrations in
conjunction with changes in organic acid concentrations caused by vegetation mortality.
AnUUEb: This research involves field sampling and analysis comparing the mineralogical and organic
acid charactenst.es of soil samples from a Mammoth Mountain high CO2 site to control soil samples
co lected from the same area that have not been exposed to elevated CO2 concentrations. This field work
will be complemented with laboratory studies assessing weathering rates of soil minerals under controlled
partial pressures of CO2 and varied organic acid concentrations.
jMus: Soil samples from this high CO, area have been collected and both chemical and mineralogical
analyses have been performed Differences between these soils and the control soils including PH, soil
torture, moisture content, surface area total carbon and elemental composition have been examined.
dentification of soil mineral phases has been achieved by XRD. Selective extractions have also been done
to assess deferences in the weatherability of the soils, and soil solutions have been analyzed for major
cations. Comparative analysts of the composition and concentrations of the organic acid in the soils is in
progress.
Papers & Publications; Stephens, J.C. and Herins I 9nnr> &«««„<. f • i • • i ^A
rr\ ™nr.ontraf A • ncnng, j. /uuu. Response of mineral weathering to elevated
cl" Vaiym8 °rgani° ^ C°nCentrati°"S '" "^ 20°° *«
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U915574
HIGHLAND MAYA MEDICAL ETHNOBOTANY IN ECOLOGICAL PERSPECTIVE
John R. Stepp
University of Georgia
Objectives/Hypotheses: Two-thirds of the world's population rely on plant based medicines for their pri-
mary health care. However, there has been little research on the interaction between cultural knowledge and
use of medicinal plants in relation to the biophysical environment. This doctoral dissertation research
involves an ethnoecological study of the most utilized medicinal plants of the Highland Tzeltal Maya in
Chiapas, Mexico. The overall research design is guided by several hypotheses related to the cultural
selection, procurement, and management of medicinal plants.
Rationale: Medicinal plant conservation is a relatively new endeavor. In recent years, there has been a
resurgenceofinterest in traditional knowledge related to plants, especially medicinal ones. This research will
add to this growing body of literature and address a significant gap by looking at traditional knowledge and
useofmedicinalplantswithinan ethnoecological framework. Several studies have indicated that indigenous
peoples have a comprehensive, scientifically accurate knowledge of their environments, and it is expected
that this research will add to this corpus. Despite many excellent general ethnoecological studies, there has
not been a major study devoted solely to the ethnoecology of medicinal plants. Besides having importance
forother research within Chiapas, this research potentially relates to ethnobotanical investigation throughout
the neotropics as many of the plants utilized by the Tzeltal are used by other indigenous groups.
Approach: This research has two interrelated domains of investigation: cognitive and behavioral This
approach allows for a fuller understanding of human-environmental relations by contextualizing human
behavior within local perceptions of the environments. The study is based primarily on ethnographic
research, which means that multiple methods, both quantitative and qualitative, are utilized and it also
dictates that a substantial amount of time is spent in the field. The research design is systematic as opposed
to interpretive and for the most part involves an explanatory (hypothesis testing) approach.
Status: During the fall of 1999,1 conducted fieldwork in Highland Chiapas in six communities in the
muncipality of Tenejapa. Spring of 2000 was spent analyzing these data. I plan to return to the field during
the summer of 2000.
gapers & Publications; Stepp, J.R. 2000. Mountain ethnobiology and development in highland Chiapas.
Mexico: Lessons in Biodiversity and Health. Mountain Research and Development 20(3).
Stepp, J.R. Ethnobiology and conservation in the highlands of Chiapas, Mexico: the Maya example, in
Montaeas del Mundo (F. Sarmiento, ed.). Quito, Ecuador: Abn Yala Press (in press).
283
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U915570
RANDOMLY AMPLIFIED POLYMORPHIC DNA PROFILE-BASED MEASURES OF
GENETIC DIVERSITY AS A BIOINDICATOR OF ENVIRONMENTAL STRESS
David C. Sternberg
Miami University
Objectives/Hypotheses; To determine the suitability of RAPD-PCR (randomly amplified polymorphic
DNA-polymerase chain reaction) based measures of genetic diversity as an alternative to current acute and
chronic toxicity tests of ecological risk in a wider variety of resource types. This preliminary study will
assess the amenability of a new set of test organisms, inhabiting streams in the alpine and Great Lakes
ecosystems, to genetic diversity-based measures that sensitively, rapidly, and inexpensively assay the impact
that anthropogenic stressors have on aquatic species. Furthermore, refinement of the RAPD protocol will
make the test easier and more reproducible allowing RAPDs to be used by a wider variety of agencies that
are seeking more sensitive bioindicators of ecosystem health.
Rationale: Currently accepted toxicity and biologically based indices have proven to be among the most
sensitive and useful measures of environmental impacts through their direct assessment of the extent to
which resource systems can harbor adaptable biological communities. These indices on the biochemical,
tit POpUlf°"' *nd commun*y levels have demonstrated that both acute and chronic exposures to
coTela to witTH? T P^T T" ^^^ >rofili"S - > —*«" ^oindicator of
Superior
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Papers & Publications; Krane, D.E., Sternberg, D.C., and Burton, G.A. 1999. Randomly amplified poly-
morphic DNA profile-based measures of genetic diversity in crayfish correlatedwith environmental impacts.
Environ Toxicol Chem 18:504-508.
285
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U915138
CHARACTERIZATION OF NON-POINT SOURCE VADOSE ZONE PESTICIDE LEACHING
AT THE REGIONAL SCALE USING A TYPE TRANSFER FUNCTION APPROACH
Iris T. Stewart
Stanford University
Objectives/Hypotheses; The objective of this research is the development of a comprehensive and versatile
protocol for the assessment and prediction of regional-scale, non-point source groundwater contamination
from agricultural chemicals, using a linear systems (transfer function) approach.
Rationale: Quantitative, regional-scale groundwater vulnerability assessments that possess the capability
of predicting concentrations in space and time are essential for current and future regulatory decisions
pertaining to the use of agricultural chemicals. A transfer function approach can yield those concentration
magnitudes without the staggering computational effort required by process-based simulations.
Approach; Transfer function models are essentially black box models that relate a given input (i e., a
pesticide application) to an output (i.e., a solute concentration distribution within a soil profile) through an
impulse response function. Central to my work is the development of 'type' transfer functions (TTFs),
designed to describe solute concentrations in space and time for a particular combination of factors relevant
to the transport processes involved. This study will aid in the understanding of the issues concerning the
application of linear systems techniques to represent and predict solute movement through the unsaturated
subsurface, especially with respect to the representation of processes such as advection, dispersion, decay,
and sorption. The use of transfer function models as predictive tools at regional scales is a new contribution.
The new approach will be developed and tested in three phases: TTF development in Phase I is based on (i)
the Fresno case history (Loague et al., Contaminant Hydrology, 29,109-136,1998), (ii) a steady-state TTF
model, and (in) three typing factors. Maps of water table solute concentrations generated for the 1172 km2
Fresno case study area show that the TTF model is capable of identifying the same areas of high groundwater
vulnerability that were predicted by the process-based simulations (Stewart and Loague 1999) In Phase
II, several sets of TTFs are identified for each relevant soil textural class (i.e., Sandy Loam, Loam, Silt
Loam Sandy Clay Loam, Clay Loam and Silty Clay Loam) with the aid of simulated stochastic data sets of
fluid flow and solute transport and a more evolved TTF model formulation. The more evolved TTF model
formulation is given in terms of effective upscaled parameters, explicitly accounts for decay and sorption,
and ,s applicable to transient flow conditions. In Phase III, the optimal set of TTFs is subsequently applied,
usmgsoils.chmatelanduse/pesticideapplication.andin-igationinformationtomakethefirst regional-scale,
quantitative groundwater vulnerability assessments for the San Joaquin Valley, one of the most intensively
farmed regions of the United States.
Status: Phase I has been completed and yielded promising results for my subsequent work. Work on Phase
^progressing well and will be finished by June 2000.1 anticipate to complete Phase III by November
Papers & Publications: Stewart, I.T. and Loague, K. 1999. A type transfer function approach for regional-
scale pesticide leaching assessments. J Environ Qual 28:378-87. FF'««<" «" ™&
286
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U915387
FROM MOTOR CITY TO GARDEN CITY: SUSTAESABILITY
AND URBAN AGRICULTURE IN DETROIT
Karl M. Steyaert
University of Michigan
Objectives/Hypotheses; This project looks at a group of urban agriculturalists in inner city Detroit The
^objectives were to: describe the agriculturalists' efforts to build healthy and sustainable communities;
analyze patterns of thought and action underlying these efforts; and propose how these patterns might be
useful in the design of sustainable community development in general.
Rationale: There are indications that conventional approaches to community development ^America's
inner cities are illogical in ecological, social, and psychological terms. Urban agriculturalists are punning
an alternative form of community building that stands in sharp contrast to conventional development.
Abroach, The data for the study was collected primarily using the ethnographic method, ; of semi-
structured interviews and participant observation, supplemented by newspaper chppmgs fl^rs and
informational brochures, Giventhes^
the personal histories of a small group of urban agriculturalists, these qualitative meth ^^£w«te
' rounds motivations,
e personal histories o a sma group o uran ,
a nuanced and flexible exploration of individuals' backgrounds, motivations, ^
structured interviews were conducted with 19 individuals directly uwolved with the
Network (DAN), an organization linking urban agriculture efforts m the city of
People interviewed are urban agriculturalists themselves, but some are mvolved *»* ?
explicit leadership or coordinating capacity. Interviews were conducted «.^*
offices of the people being interviewed. Participant observation consis ^ of mvolvemer of
sessions at urban gardens in potlucks hosted by the Detroit Agnculture Network and m DAN Counci of
Elders meetings, as well as a number of informal visits to the agriculturalists and their gardens over
course of a year.
Status: The research project has been completed and a Master's thesis paper has been produced.
Papers & Publications; None at this time.
287
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U915591
URBAN FORM AND THERMAL EFFICIENCY: HOW THE DESIGN OF CITIES
CAN INFLUENCE THE URBAN HEAT ISLAND EFFECT
Brian Stone
Georgia Institute of Technology
Objectives/Hypotheses; The intent of this research is to quantify the thermal contribution of individual land
parcels to the development of a surface heat island in the metropolitan region of Atlanta, Georgia.
Specifically, this project seeks to determine whether an expansive, low density pattern of residential
development produces more or less radiant heat per single-family dwelling than a compact, high density
pattern. It is hypothesized that higher density forms of residential development will be found to contribute
less thermal energy to regional heat island formation than lower density forms.
Rationale; A steady increase in mean global temperatures and violent weather over the previous several
decades has provided circumstantial evidence that significant changes in global climate are underway.
Contributing to the potential for detrimental ecological impacts within cities, in particular, is a more
regionalized process of temperature change known as the urban heat island effect. Measured as the
temperature differential found between urban centers and their rural peripheries, the urban heat island effect
is produced from the displacement of vegetation by urban construction materials such as asphalt, cement,
and roofing shingle (Oke, 1987). Unable to offset heat gain through the natural cooling process of evapo-
transpiration, non-vegetative materials tend to absorb large quantities of heat during the daylight hours. The
slow release of this stored heat energy serves to elevate urban temperatures by several degrees over adjacent
rura! areas. The thermal "islands" that result from this temperature differential have substantial implications
for energy consumption, urban air quality, ecosystem vitality, and human health (Cardelino & Chameides,
Approach; The research design for this project utilizes high-resolution thermal data (ten meters) collected
by the National Aeronautical and Space Administration's (NASA) Global Hydrology and Climate Center
over the metropolitan region of Atlanta, Georgia. With the aid of this thermal data, the quantity of radiant
heat energy emitted by approximately 116,000 single-family residential parcels is calculated and incor-
porated into a parcel-level database assembled from city and county tax records. A measure of parcel "net
SZiTTT ',S ? u° qTtify the contribution of each single-family parcel to surface heat island
InZZ'J ff T fT ^ ^ '^^ ** ^^ *** ^ mM tO aCCOUnt for
and indirect effects of urban design on urban heat island formation.
Status; The analysis has been completed.
Papers & Publications; None at this time.
288
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U915172
REDUCTIVE TRANSFORMATION OF AGROCHEMICALS IN MODEL
AQUEOUS SYSTEMS: ROLE OF FERROUS IRON SPECIATION
Timothy J. Strathmann
The Johns Hopkins University
Obiectives/Hvnotheses: To examine the abiotic reductive transformation rates of carbamate pesticides
(Oxamyl, Methomyl, and Aldicarb) in the presence of various soluble and mineral-adsorbed Fe(II) species
present in aqueous-soil environments.
Rationale: High concentrations of Fe(II) are often present in anaerobic
primarily from chemical and microbial reduction of Fe(III)-contammg minerals. Fe(II) i
has been found to be a highly reactive reductant, which may determine the fate of many «
organic compounds. Considering its potential importance, very fewstud.es have been ^
well-characterized model aqueous systems to examine the reactivity of Fe(II) with ™£
agrochemical, Especially lacking is information pertaining to the effects of PH morgam
solution composition, and the presence of mineral surfaces on agrochermcal transfonnation rates
mining these variables in closely controlled model systems will help us ^*°?^
interactions that are responsible for reductive transfonnation of important classes of agrochermcals.
and
Exa
h: Kinetic experiments are conducted in clean and sterilized ^
me potential for various Fe(II) species to reduce carbamate pesticides m
ned b measurin pseudo Ist-order rat
enme potential for various Fe(II) speces to reuce cara
Effects of Fe(II) speciation are determined by measuring pseudo Ist-order rate
<^^
o^^^
conductedunderthesameconditions(e.g,pH,buff^^
to account for pesticide transformation processes not involving the Fe I 1 ' Pf^S^^duct
temperature dependence of the rate constants will also be evaluated. ^^^^^^
fo^ationaremonitore^^
mation products are characterized by chromatographic comparison with authentic
spectral analysis,
Status: Experimental work pertaining to
Fe(Il) adsorbed onto mineral surfaces has been compicu^^^^j r- - ^ 2QO j
by (c) organic-ligand complexed Fe(II) is in progress. The project will be compie y
T T onH <;tnne A T 2000. Abiotic reduction of the pesticides Ox-
Papers& Publications: Strathmann, T.J. and Stone A. . M Nationai Meeting of the American
amyl and Methomyl by Fe(II): reaction kinetics and mechanism NationalJVU*, g
Chemical Society, Division of Environmental Chemistry, (m press, extended abstract)
Strathmann,T,.andStone,AT. 2000. Abioticreduc^
role of mineral surfaces. National Meeting of the American Chem.cal Soc.ety, Uivis
Chemistry, 40(1): 141-144. (extended abstract)
Strathmann, T,. and Stone, A.T. 1999. Ab^tic.reduction>«*£
dissolved ferrous iron. National Meeting of the American Chemical Society,
Chemistry, 39(1): 18-20. (extended abstract)
289
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U915420
THE RETURN OF THE FOREST: URBANIZATION AND REFORESTATION
IN THE NORTHEASTERN UNITED STATES
Ellen Stroud
Columbia University
Objectives/Hypotheses; This project investigates the relationship between the regrowth of forests in the
northeastern United States during the twentieth century and the concurrent growth of northeastern cities.
As 1 analyze the processes of reforestation in the northeastern United States, I am emphasizing the
interaction between the city and its hinterlands, arguing that it is no coincidence that the most heavily
urbanized part of the country has experienced the most dramatic return of woodlands. Rather my hypothesis
is that the desires and physical needs of city people encouraged and required the return of the forest.
Rationale: This study will demonstrate the historical and ecological specificity of the transformation of the
northeasternlandscape.andthedifflcultiesinherentin using the experience of the northeastern United States
as a model for forest policy elsewhere. In addition, in establishing the importance of both intended and
incidental results of human action in the return of northeastern forests, this project will encourage policy-
n"atral landscapes ^^ "* ^ ^ environmertts as inteSral components of complex and dynamic
™
rm , types °f northeaster" ^ests: watershed forests, "wild" forests,
farm woodlots industrial forests, and forested suburbs. These five forest types are found throughout the
rc\Tm?ch 'I *"** v "* ***"? " P™S*1™™ -d New Hampshire, and have completed
2oorrenaip n r verm°n' and Majne- i ^ * ^ «* ****** ™ ^^ «*** ^
2000, when 1 will begin my Massachusetts research.
W Stroud,E. Bringing back thetrees: urban watershed protection and reforestation
at *e ^^ 19" American Historical Association meeting,
of " eSUre' C°Untiy W°rk' "« ** retura of
American Society for Environmental History meeting, Tucson, AZ.
** retura of the fo^- Presented at the
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U915641
A MODELING INVESTIGATION OF THE EFFECTS OF SOLID-PHASE
CLOUD HYDROMETEORS IN CONVECTIVE CLOUDS
ON CHEMICAL DISTRIBUTIONS AND DEPOSITION
Amy L. Stuart
Stanford University
Objectives/Hypotheses; The goal of this study is to improve our understanding of the impacts of con-
vective clouds on air-borne chemical distributions and acid deposition, through a numerical modeling
investigation of the effects of interactions of ice-phase hydrometeors. My hypotheses include that solid
phase processes lead to increased, acid deposition, to decreased transport of oxidized nitrogen species to the
upper troposphere where they impact the chemistry of ozone, and to increased rates of photolysis chemistry
in the upper troposphere.
Rationale: Convective clouds impact air-borne pollutant concentrations and precipitation chemistry by
processing trace chemicals. They process chemicals through air convection, by providing surfaces for
gas-to-particle conversion and reaction, and by scattering and absorbing light. Due to their complexity, the
details of many cloud processes, particularly interactions of chemicals and radiation with solid hydro-
meteors, are not well understood. Examples of these interactions include chemical sorption, retention of
chemicals during hydrometeor freezing, chemical reactions in/on solid hydrometeors, and changes in
chemical photolysis rates due to hydrometeor scattering and absorption. Previous modeling studies that
include interactions of solid hydrometeors with chemicals use differing simplified representations and give
no consistent picture of their effects.
Approach: I am implementing several representations of solid hydrometeor interactions into a three-
dimensional cloud model, in order to systematically investigate the range of their potential impacts on
chemistry. Data from field measurements, including the STERAO-A field campaign, is being used for
comparison and validation of modeling results.
Status; I currently have results from model simulations including two distinct representation of chemical
transfer during hydrometeors freezing. Results indicate that allowing species to be retained in solid
hydrometeors, rather than evaporating, may significantly impact the fate of highly soluble species, leading
to larger total surface deposition and to chemical mass losses, rather than accumulation, in storm anvil air.
Papers & Publications: Stuart, A.L., Barth, M.C., Skamarock, W.C, and Jacobson, M.Z. 1998. Solid
microphysics and chemistry interactions in thunderstorm simulation using a three-dimensional cloud model.
Eos Supplement, Transaction, American Geophysical Union, 1998 Fall Meeting.
291
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U915408
FOREST INTERIOR SONGBIRD DIVERSITY AND BREEDING SUCCESS AS A FUNCTION
OF TOPOGRAPHY AND CLIMATE IN THE MID-ATLANTIC HIGHLANDS
Brian R. Sturtevant
University of Maryland
Objectives/Hypotheses; The primary objective of this study is to establish an ecological linkage between
d"Cmta "^^^^
wnem-tantcgans egon
(MAHR) of the eastern Un.ted States. I hypothesize that food resources increase with primary productivity;
thus in the absence of edge effects, forest-interior bird density, diversity and reproductive success are
controlling forest productivity (i.e., rainfall, slope position, and moisture avail-
BtitaBil* While forest fragmentation is a key factor driving source-sink population dynamics for forest
t "fT" ' """"^ aCCOUnt ** °b*™d spatial ** temporal variability in the
" K1"0168-, " m°re bCal SCal6' f°°d reS°Urces critical to the breeding success
T ^ CTIated Whh ^ Same 6daphic ch^cteristics (i.e., soil moisture and
- Topography controls spatial variation in forest productivity by
nUtriCntS' 3nd C°ntr0llinS m°isture loss through solar radiation
' nS m°sture oss trough solar radiato
^ pr°ductivi* is further ^^diHed by regional precipitation patterns
mte8ratl°n tOP°graphiC 3nd Climatic data -i* current land-us
reaton .
u^±tn ? mte8ratl°n f tOP°graphiC 3nd Climatic data -i* current land-use
patterns will significantly improve large-scale evaluation of avian habitat quality.
^ t0P07aPhic/envi^ental controls on forest energy flow to higher
of the prima^literatur. This
and -
- f- of the
canopy structure taken within each site will evaluate thfconS^nfl MeaSUrfements of tree stem and
bird habitat quality. A statistical model will be deve boed to re^f § T* °f VegCtatl°n ^'^ °"
topographic moisture indices. Multi J
topo^aphic position, and results wiH be
e W*b control of energy flow to
,-n
models relating forest pLucti^r^^^^^ ^^ APPalachians- Preliminary
important dlfferences between
climate of the AP. Survey n^t. teTT "^ T-^ t0 tOP°graphy
topography differed be Jen the studTareastd was ^rL IT ^ ' ^ *"* ^"^ reSP°nSe *
density and diversity offorestint^
and from dry to wet topographic positions PlV"Cr,ea/edb°*fromd^towetPhysiograPh1c provinces,
climate, topographically^ JSSZ^S " * "*** "*"* *
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Papers & Publications: Sturtevant, B.R. and Seagle, S.W. Avian productivity within topographically
diverse landscapes: tinkingecosystemtrophicstructure, plant-herbivore interactions, and landscape ecology.
(submitted to Bioscience)
Sturtevant, B.R. and Seagle, S.W. Relating food abundance for avian insectivores to topographic resource
gradients: 'does landscape topography influence trophic interactions and energy flow? Poster presentation,
5th World Congress of the International Association of Landscape Ecologists, Snowmass, CO, July 1999.
Sturtevant, B R and Seagle, S.W. Forest songbird diversity and fledgling success as a function of
topography and climate in western Maryland. Paper presentation, Joint Millennial Meeting of the American
Ornithologists' Union, the British Ornithologists' Union, and the Society of Canadian Ornithologists. St.
John's, Newfoundland, Canada, August 2000.
Sturtevant, B.R. and Seagle, S.W. Forest songbird diversity and fledgling success as a function of topo-
graphy and climate in western Maryland. Paper presentation, 7th Annual Conference of the Wildlife Soc.ety,
Nashville, TN, September 2000.
293
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STAR Graduate Fellowship Conference
U915599
SCIENCE TO ACHIEVE RESULTS FELLOWSHIP
Tim Sulser
University of Florida
Objectives/Hypotheses; Requirements for monitoring and evaluation need to be harmonized with the
realities of work in the field. For community-based agroforestry extension, monitoring and evaluation is
critical for assessing efficacy of projects and for planning improved future efforts. Tools for project
assessment that can be continually updated and eventually form a database of project experience are essential
for extension programs that have limited time, labor, and finances. The reality of field work means that
monitoring and evaluation should be field practical, that is: 1) be quick and inexpensive, and 2a) provide
direct, productive results or 2b) be an integrated element for project productivity. Project efficacy, defined
by sustainability in three different realms (socio-economic, socio-cultural, and biophysical), can be quickly
and efficiently measured through analysis based on ethnographic field data. Research tools to be employed
in project sustainability assessment will be spreadsheet modeling at the socio-economic level and
Participatory Rural Appraisal (PRA) at both the socio-cultural and biophysical levels. These tools will
identify key household and community background factors for project effectiveness. Also, systematic biases,
project strengths and weaknesses, and overall constraints on agroforestry will be revealed through this
research. The paramount concern for all extension work needs to be the achievement of specific and
valuable objectives leading to the overall goal of improving social well-being. Also, as the extension project
that will be the site for this applied research is managed by a conservation organization, the goal of
improving local social well-being is commensurate with the goals of forest and biodiversity conservation.
Therefore, monitoring and evaluation of both conservation and community development goals are merged
into a single methodology.
Rationale: (Not received at time of printing.)
Approach: (Not received at time of printing.)
Status: In progress.
Papers & Publications; None at this time.
294
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U915642
THE MECHANISM OF CADMIUM NEPHROTOXICITY
Weifeng Tang
University of Rhode Island
Objectives/Hypotheses: The mechanism underlying chronic cadmium (Cd) nephrotoxicity remains to be
understood The purpose of my study is to demonstrate that: 1 ) renal mitochondrial damage upon cadmium-
metaJlothionein (CdMT) administration is caused by Cd++, and 2) mitochondria are the critical executioner
of Cd-induced apoptosis in kidney.
Rationale: Under chronic Cd exposure, Cd is primarily taken up by the liver, where Cd induces synthesis
ofmetallothionein (MT) and binds to it to form CdMT complex. Hepatic CdMT is transferred to kidneys
and causes proximal tubular damage. Mitochondria are one of the earliest target organelles of Cd nephro-
toxicity and apoptosis is the earliest cell response for Cd exposure. The mechanism underlying the renal
mitochondrial dysfunction and the relationship between mitochondrial damage and apoptosis caused by Cd
exposure is not fully elucidated,
Approach: It is generally agreed that chronic Cd-induced nephrotoxicity is caused by CdMT that is
^ynti^e"d in and transferred from liver. Thus, acute CdMT inject.on has been pensively usec to study
r
yne n an rans . ,
the mechanism of Cd-induced nephrotoxicity. Rats will be injected ,p with 0.3 mg Cd as CdMT/kg. ^After
6, 8, and 12 hr of CdMT injection, 6 animals/group will be sacrificed. Renal cortical mitochondria wiU be
, , ,
isolated and mitochondrial respiratory function will be analyzed For in
mitochondria isolated from untreated rats will be incubated with 0.1-2 uM Cd as CdC12 at 25 C for 1 mm
followed by measurement of mitochondrial respiratory functions.
Inordertostudytheroleofmi^^
CdC12 for 5 hr At the end of Cd exposure, the cells will be washed and cultured for up , to >U ^ hr- M to
chondrial membrane potential, cytochrome c release, caspase-3 activation and DNA ^f^bllnt
analyzed. In some cases, the cells will be co-treated with a caspase-3 inhibitor or mitochondnal membrane
permeability transition pores blocker.
nephrotoxicity is caused by Cd++. Currently, we are working on the second objective.
Pane.. * Puhlications: Tang, W. and Shaikh, Z.A. 2000. ^ ^ochondrial damage upon cadmium-
metallothionein administration is due to Cd++. Toxicol Sc. 54:284. (abstract)
295
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U91S528
IMPACT OF CATTLE GRAZING AND SUMMER AND WINTER DROUGHT ON SOIL MITE
POPULATIONS IN THE NORTHERN CHIHUAHUAN DESERT
Hilda S. Taylor
University of Texas, El Paso
Objectives/Hypotheses; There are two objectives to this research study: 1) to determine if soil mites can
be used as bioindicators of disturbance and recovery in desert ecosystems, and 2) to determine the impact
of these disturbances on mites. The disturbances include multiple environmental (natural and anthropo-
genic) stressors. Investigations on how these stressors interact to impact desert soil ecosystems is essential
to the development of adequate rangeland management practices, and to an understanding of desertification.
I hypothesize that multiple stressors will have a greater impact on soil biota than a single stressor.
Hypotheses will be tested using biodiveristy indices, population densities, and community composition
comparisons.
Rationale; Developing and improving technologies to monitor and assess the natural resources of range-
lands have been of major concern since the early 1 900s. Therefore, developing a better understanding of the
ecological processes in desert environments is essential. The results from this study can expand our
understanding of the ecological processes in desert environments, and can be incorporated into technologies
(methodologies) currently being used to manage and assess resource conditions in rangelands.
Accroach: This experiment was originally set up in 1993-94 to investigate the effects of environmental
stressors on ecosystem properties and processes, and is part of an Environmental Protection Agency study
of multiple stressors in arid ecosystems. The treatments are as follows: summer drought plots under
ram-out shelters for the 4-month rainy season, winter drought plots under "rain-out" shelters for 8 months,
nutrientdepletion-plotstreated with glucose to stimulate microbial growth, which immobilizes the nutrients
in the microbial biomass, shrub removal-shrubs are cut to the ground and any sprouts are treated with
herb,c,de grazing by livestock-intense grazing at the rate of 40 head/hectare for 24 hours, fire-treated plots
that were burned early ,„ summer, the timing coincides with the first convectional storms of the year and the
first potential for natural fire. The experimental design consists of a complete randomized block with six
plots per block. The treatments have been assigned at random as the main effects in each of the blocks.
Subplots (within each plot) have been assigned the following sub-treatments at random: burn, nutrient
depletion, burn and nutrient depletion control, winter rainout, summer rainout, and rainout control. The
col ection of soil mites was initiated on 06/97, during the third year, which is the end of the exposure to the
multiple stressor treatments, and is the beginning of the 3-year recovery period.
Staius: Preliminary data suggest that the density and diversity of soil mites is directly correlated with winter
and summer precipitation. I have completed all of my coursework and anticipate working full time
processing samples the coming year. I expect to complete this research by May 2002.
r^' H/" ^^ W'P" Hefrick' J'E" Guerrero> R" and Whitford,W.G. 1998.
(32):I 15 t0 tCrmite ^^ in the n0rthem Chihuahuan Desert (Isoptera).
o n °f ******* contamination in the El Paso/Ciudad
Border wTr. Fr M T 'T T of A8riculture *««* Service Proceedings RMRS-P-5. Cross
Border Waters: Fragile Treasures for the 21st Century (abstract) pp. 304-305.
296
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STAR Graduate Fellowship Conference
Moreno, I,, Jimenez, H.R., Padilla, D.I., Taylor, H.S., and Mackay, W.P. 1999. The current status of the
red imported fire ant, Solenopsis invicta, in El Paso, Texas. Proceedings of 1999 Imported Fire Ant
Conference. Clemson University, Department of Entomology, and Berkeley County Extension Office,
South Carolina, pp. 93-99.
Taylor, H.S., Mackay, W.P., Herrick, I.E., Guerrero, R., and Whitford.W.G. 2000. Lack of impact of
livestock grazing on subterranean termite activity in the northern Chihuahan Desert, (accepted for pub-
lication in Journal of Arid Environments)
297
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U915611
THE POLITICAL ECOLOGY OF SUSTAINABLE AGRICULTURE
IN CHINA: NATIONAL GOALS AND FARMER REALITIES
Brian J. Thomas
University of Oregon
Objectives/Hypotheses: In spite of growing awareness of the importance of sustainability, many farmers
inChinaarestillpursuingenvironmentallydamagingagriculturalpractices.Researchinecologicalagriculture
shows potential for developing sustainable systems. Over 1000 demonstration villages have been established;
however, the wide spread implementation of these systems are being hindered by economic development
priorities and a lack of local control and local agricultural institutions.
Rationale: The last two decades have been a defining period for China. The economic and agricultural
reforms that took place during this time have had major social, economic, and environmental impacts.
Although reforms appeared to cause a rapid increase in agricultural production, productivity largely leveled
off in the 1990s. Increasing environmental problems caused by agricultural intensification have brought into
question many of the currenttrends in agricultural practice. At the national level, there is a growing awareness
oftheimportanceofencouragingsustainableagriculturalproduction. National agricultural po-licy has begun
to consider issues of sustainability. Research in ecological agricultural systems shows great potential for
creating sustainable growth. These systems seek to integrate past and present agricultural techniques to create
economically and environmentally sustainable practices. China has created over 1,000 demonstration
ecological villages where sustainablepracticesare being applied. Nonetheless, many far- mers are continuing
to contribute to environmental degradation by increasing use of intensive agricultural practices.
Approach; Rural Jiangsu province provides an excellent example of the various political, economic, and
social forces that are influencing how rural farmers produce food. Jiangsu province is a highly productive
region and has had a long history of sustained agricultural production. At the same time, the province has
been under increasing pressure to dedicate resources toindustry while extracting more and more food from
the land. While in Jiangsu, I will conduct semi-structured interviews with individuals who are researching
and working in demonstration villages. Based on visits to these villages and observations of agricultural
practices, I will evaluate local opportunities and obstacles to widespread application of these systems. Using
aggregate data, I will also trace how these agricultural practices have changed with national policy.
Status; Field work will be conducted during the summer of 2000.
Papers & Publications: None at this time.
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CHEMICAL AND BIOLOGICAL ASSESSMENT OF THE AQUATIC
ECOSYSTEM OF THE HOUSTON SHIP CHANNEL
Renard Thomas
Texas Southern University
Qhiectives/Hvnothescs: Anthropogenic pollutants, industrial and domestic, are an increasing concern for
the Galveston Bay System. The Houston Ship Channel (the upper portion of this bay system) and the entire
Galveston Bay System have a multiplicity of uses—industrial, commercial fisheries, navigational and
recreational. All of which occur in close proximity to large and dense metropolitan and industrial com-
munities. Domestic and industrial discharges, ship/barge/recreational traffic, fresh water inflows from the
various bayous and lakes contribute the large variation in the character of this aquatic ecosystem. Inductive
Coupled Plasma and Ion Chromatography were the chemical analyses performed on aqueous ship channel
samples. Metals such as barium, chromium, molybdenum, silver, beryllium, antimony, lead, and mercury
were found through out the Bayou Reach of Houston Ship Channel. Titanium, manganese, copper, zmc,
nickel, and selenium concentrations were found to be higher in regions closer to the Galveston Bay.
Aluminum, vanadium, iron, and arsenic were found at various sites within the upper portion of the ship
channel. Relative high concentrations of ammonia, sulfate, and chloride were detected Surprisingly the
maximum amounts of phosphate and nitrate detected were low. Bioindicators (i.e., plankton andkrther Irv-
ing organisms) were correlated with analyses as additional parameter to evaluate this ecosystem. The future
focus of this work will include a survey of the sediment layer with the associated biological monitoring
program in an effort to better understand the actual and potential impacts of these environment1 con-
taminations on the benthic community of plants and animals and bioindicators, and effects of exposure to
aquatic contaminants.
Rationale: (Not received at time of printing.)
Approach: (Not received at time of printing.)
Status: (Not received at time of printing.)
Papers & Publications: (Not received at time of printing.)
299
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U915163
RETHINKING DECISION-MAKING IN THE FACE OF SCIENTIFIC UNCERTAINTY:
INSTITUTING PRECAUTION IN ENVIRONMENTAL HEALTH POLICY
Joel A. Tickner
University of Massachusetts, Lowell
Objectives/Hypotheses: This research attempts to develop a heuristic framework and to suggest policies
to implement the Precautionary Principle in U.S. environmental health policy decision-making through an
in-depth case study examination of the two main components of the Principle, as well as an overview of two
additional components recently recognized as critical for operationalizing the solutions/preventive planning
("foresight") aspects of the Principle and translating the Principle into a U.S. context
Rationale: The Precautionary Principle has become a recognized guiding principle of international
environmental law and policy. The principle was developed to guide decision-makers in cases where threats
of serious harm existed to complex systems, yet available scientific evidence was insufficient to determine
the specific types and potential magnitude of that harm. The Principle has been incorporated into
environmental legislation in the European Community. It has been debated in Europe for two decades, yet
discussion of the Principle is just beginning in the United States. Given that the U.S. environmental
regulatory system is substantially differentthanthe European system (more specificity, less flexibility), there
is a need to understand how it can be implemented in a U.S. context.
Approach; The Precautionary Principle has generally been discussed in the literature and policy as having
two main components: action in the face of scientific uncertainty; and shifting the burdens of proof onto
proponents of a potentially harmful activity. Through case studies on the Institute of Medicine Committee
on Agent Orange and New Chemicals regulation under the Toxic Substances Control Act, I examine these
components in detail; how they have or have not been implemented in a U.S. context; and lessons learned
for more effectively applying them in public policy. I also examine how science and policy interact in
influencing the implementation of the Precautionary Principle. As more recent analysis has suggested that
assessment of alternatives to potentially harmful activities and democratic decision-making structures are
critical to implementation of the Principle, I examine these components in detail. I then develop a normative
framework for implementing the Precautionary Principle in environmental health policy and examine
influences, opportunities and barriers to such a structure in the United States.
Status; All background research is completed. I have finished drafts of the two case study chapters and
additional background analysis. I plan to defend the dissertation in September 2000.
Papers & Publications: Raffensperger, C. and Tickner, J. 1999. Protecting public health and the environ-
ment: implementing the precautionary principle. Washington, DC: Island Press.
Additional editorials and short articles in Nature, Endocrine/Estrogen Newsletter, and other professional
newsletters. One additional book chapter in progress. Several professional conference presentations/papers,
presentation to government decision-makers in the United States and abroad, and two foundation-funded
projects have resulted from this research.
300
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U915534
UNDERSTANDING COVARIANCE FUNCTION DYNAMICS FOR IMPROVING
INSECT SPATIAL AND TEMPORAL MANAGEMENT
Patrick C. Tobin
The Pennsylvania State University
Objectives/Hypotheses; The spatial and temporal dynamics of insect herbivores are of considerable inter-
est in ecology, and the implications of these dynamics in competition, dispersal, predator-prey relationships,
sampling, and the implementation of pest management strategies are profound. Recently, problems in
populationbiology have received considerable geostatistical treatment. Geostatistics are useful in estimating
spatial covariance functions, which can be modeled and used in interpolation algorithms, such as kriging.
Insect populations, however, are extremely dynamic and change over varying temporal and spatial scales.
Hence, the expectation of a covariance function for a certain herbivore population and field is constantly
subject to change, rendering its estimation rather myopic. My research focuses on the dynamics of
covariance functions in insect populations.
Rationale: Enhancing our understanding of insect population dynamics in space and time is paramount to
the development of improved pest management strategies.
Approach; I am investigating theoretical dynamics of covariance functions by simulating, using Markov
random fields, the spatial and temporal patterns of insect herbivores and their natural enemies. I then intend
to estimate time-specific auto- and cross-covariance functions using geostatistics. Lastly, I will compare
theoretical expectations with empirically derived functions obtained from analyses of field-collected data.
Status; I am currently a Ph.D. Candidate in my third year of study. I am in the Penn State Operations
Research Program and based in the Department of Entomology.
Papers A Publications; Nagarkatti, S., Tobin, P.C., and Saunders, M.C. 2000. Diapause induction in the
grape berry moth, Endopiza viteana (Clemens) (Lepidoptera: Tortricidae). J Environ Entomol (in review)
Saunders, M.C. and Tobin, P.C. 2000. Grape cane gallmaker, Ampeloglypter sesostris (Leconte) (Cole-
optera: Curculionidae), and its impact on cultivated grapes. J Econ Entomol (in press)
Gray J P Maddox, C.W., Tobin, P.C., Gummo, J.D., and Pitts, C.W. 1999. Reservoir competence of
Carcinops'pumiHo (Erichson) (Coleoptera: Histeridae) for Salmonella enteritidis (Gaertner) (Eubactenales:
Enterobacteriaceae). J Med Entomol 36:888-891.
Tobin, P.C. and Pitts, C.W. 1999. Dispersal of Muscidifurax raptorellus Kogan and Legner (Hymenoptera:
Pteromalidae) in a high-rise poultry house. Biol Control 16:68-72.
Tobin, P. C, Fleischer, S.J., and Pitts, C.W. 1999. Spatio-temporal dynamics of resident and immigrating
populations of Carcinops pumilio (Erichson) (Coleoptera: Histeridae) in high-rise poultry facilities. J Med
Entomol 36:568-577.
Pitts, C W Tobin, P.C., Weidenboerner, S., Patterson, P.H, and Lorenz, E.S. 1998. Reducing larval house
fly, Musca domestica L., populations in a high-rise poultry house utilizing in-house composting. J Appl
Poultry Res 7:180-188.
301
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U915463
ADOLESCENCE AS A CRITICAL PERIOD FOR NICOTINE-INDUCED
NEUROTOXICITY IN THE DEVELOPING BRAIN
Jennifer A. Trauth
Duke University
Objectives/Hypotheses; To elucidate mechanisms of nicotine-induced neurotoxicity in the context of
central nervous system development. Additionally, to determine whether critical periods exist for these
mechanisms.
Rationale; In the United States, at least 25% of adolescents smoke, with countless more exposed to
secondhand smoke. Previous studies in animals and humans have demonstrated that gestational exposure
to nicotine or cigarette smoke results in increased perinatal morbidity and mortality, long-term behavioral
disruption and altered neurochemistry. It is unclear whether this period of vulnerability extends into later
development, up to adolescence, when many synaptic connections are still being forged and others deleted.
Since the majority of smokers begin their habit during adolescence, it is critical to determine if the
adolescent brain is also vulnerable to nicotine-induced neurotoxicity, either through overt cell loss and/or
functional alteration of synaptic activity. These issues may affect learning and behavior as well as success
(or failure) of smoking cessation attempts. Overall, this research will impact on regulatory issues involving
tobacco and nicotine and, hopefully, raise public awareness about these commonly used products.
Approach; Rats are exposed to nicotine via osmotic minipumps and compared across different exposure
periods. Prenatal exposure begins on gestational day 4, with exposure continuing until gestational day 21.
Adolescent exposure extends from postnatal (PN) day 30 to 47 and adult exposure from PN90 to PN107.
Several parameters are measured both during and up to several weeks following the exposure period in a
variety of brain regions. Total cell number is determined by assaying DNA content. Nicotinic receptor
number is determined by ligand-binding assay. Expression of various RNA transcripts are assessed using
a slot-blotting technique. Synaptic function is assessed via neurotransmitter content turnover and release
using HPLC, enzyme assays and radioligand binding. Finally, behavioral tests will assess effects on general
activity and learning/memory.
Status: Currently, assessment of catecholaminergic function and behavioral tests are in progress Work has
already been completed with c-fos and p53 mRNA expression, nicotinic receptor binding, DNA content,
membrane protein levels, and cholinergic synaptic activity.
Papers & Publications; Trauth, J.A., Seidler, F. J., McCook, E.G., and Slotkin, T.A. 1999 Persistent c-fos
mC°tlne In deVel°ping mt brain reSions: interaction with hypoxia. Pediatric Research
Trauth, J A., Seidler, F.J., McCook, E.G., and Slotkin, T.A. 1999. Adolescent nicotine exposure causes
persistent upregulation of nicotinic cholinergic receptors in rat brain regions. Brain Research 851:9-19.
Trauth, J.A., Seidler, F.J., and Slotkin, T.A. An animal model of adolescent nicotine exposure: effects on
gene expression and macromolecular constituents in rat brain region. Brain Research (in press)
Trauth j. A, McCook, E.G., Seidler, F.J., and Slotkin, T.A. Modeling adolescent nicotine exposure: effects
on cholinergic systems in rat brain regions, (submitted for publication)
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Trauth, J.A., Seidler, F.J., and Slotkin, T.A. 1998. Prenatal nicotine exposure evokes long-term over-
expression of c-fos proto-oncogene in the CNS. The Toxicologist 42:121.
Trauth, J.A., McCook, E.G., Seidler, F.J., and Slotkin, T.A. 1999. Does the vulnerable period for
developmental neurotoxicity of nicotine extend into adolescence? The Toxicologist 48:291.
Dam, K., Crumpton, T.L., Trauth, J. A., Seidler, F. J. and Slotkin, T.A. 1999. Effects of neonatal chlorpyrifos
exposure on nuclear transcription factors involved in CNS cell differentiation. FASEB Journal 13(5):LB 128.
Trauth, J.A., Seidler, F. J., and Slotkin, T.A. 1999. Prenatal nicotine exposure induces genes associated with
apoptosis in the developing brain. FASEB Journal 13(4):A137.
Trauth, J.A., Seidler, F.J., McCook, E.C., and Siotkin, T.A. Adolescent nicotine exposure causes persistent
changes in rat brain. The Toxicologist (in press)
303
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U915532
MACROALGAL MEDIATION OF DISSOLVED ORGANIC NITROGEN
DYNAMICS IN A TEMPERATE COASTAL LAGOON
Anna C. Tyler
University of Virginia
Objectives/Hypotheses: To determine controls on dissolved organic nitrogen (DON) distribution and
transformation across a nutrient gradient in a temperate coastal lagoon. More specifically, to: 1) quantify
the temporal and spatial patterns of standing stock concentrations and benthic-pelagic fluxes of dissolved
N and to partition the DON pool into specific compounds, 2) determine the role that macroalgae play in
regulating DON fluxes, and 3) estimate the turnover rates of N by macroalgae.
Rationale: Nitrogen (N) is considered to be the primary limiting factor in temperate coastal ecosystems and
increased N loading has had drastic impacts on many systems. DON, an important component of the nitrogen
pool, is often ignored. In shallow coastal lagoons, benthic-pelagic coupling is important and benthic primary
producers dominate. Opportunistic macroalgae dominate anthropogenically impacted lagoons. In spite of
the importance of both DON and macroalgae in shallow coastal systems, little is known about benthic-
pelagic fluxes of DON or the impact that macroalgae have on DON dynamics.
Approach; This study takes place along a nutrient input gradient in Hog Island Bay, a macroalgal-dominated
lagoon at the Virginia Coast Reserve LTER project. Macroalgal mediation of benthic-pelagic DIN, total
DON, urea and amino acid fluxes will be measured experimentally using sediment cores incubated with and
without macroalgae. The uptake capacity and Michaelis-Menten uptake parameters of specific DON com-
pounds (urea, amino acids) will be estimated for a variety of different macroalgal species. The turnover of
N by macroalgae will be estimated in field experiments using 15N labeled macroalgae. The results of the
above experiments, combined with bimonthly field surveys of macroalgal biomass and sediment and water
column nutrients, will enable me to determine the importance of macroalgae to system-wide DON dynamics
and nitrogen retention.
Status: I expect to complete field and laboratory work by the fall and to finish writing by spring 2001.
Papers & Publications; Tyler, A.C., McGlathery, K.J., and Anderson, I.C. Macroalgal mediation of dis-
solved organic nitrogen fluxes in a temperate coastal lagoon. Estuarine, Coastal and Shelf Science
(submitted)
McGlathery, K.J., Anderson, I.C., and Tyler, A.C. System metabolism in a macroalgal-dominated coastal
lagoon. Marine Ecology Progress Series (submitted)
Tyler, A.C. and McGlathery, K.J. 1999. Uptake of specific organic nitrogen compounds by macroalgae in
a shallow, coastal lagoon. Estuarine Research Federation International Conference, New Orleans, LA.
Tyler, A.C., McGlathery, K.J., and Anderson, I.C. 1999. The influence of macroalgae on fluxes of organic
Fe NM m a C°aStal lag°°n' American Society of L>mnology and Oceanography Conference, Santa
304
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U915349
AIRBORNE MEASUREMENTS OF CLOUD CONDENSATION NUCLEI
Timothy M. VanReken
California Institute of Technology
Objectives/Hypotheses: The goal of this research is to develop an effective instrument for accurately
classifying cloud condensation nuclei (CCN) according to their critical supersaturation. The new instrument
will be sufficiently robust and compact to allow its unattended use aboard small research aircraft.
Rationale: Although several instruments have been used to measure CCN from airborne platforms, recent
research has raised significant questions regarding the ability of these instruments to classify CCN according
to critical supersaturation. Although single supersaturation measurements are valuable, accurate CCN
spectra would provide greater insight into several outstanding questions in cloud physics research. Such data
are particularly valuable with regard to the indirect forcing of aerosols, perhaps the least understood term
in the global radiation budget. Current assumptions regarding indirect aerosol forcing represent a wide array
of conclusions based on a sparse data set. Accurate in situ measurements are needed to correct this
deficiency.
Approach: The CCN measurement is a very sensitive one—the supersaturation range of interest is generally
from 0.01% to 1 %. Achieving and maintaining such small supersaturations is a significant design challenge.
The instrument must also accurately resolve individual particles according to supersaturation, the critical
drawback of several current instruments. In order to gain a better understanding of the complex interactions
involved in CCN activation, detailed simulations of the performance of the new instrument will be used m
conjunction with the rest of the design process.
Status: Substantial time has been spent in the field using earlier CCN instruments, resulting in an improved
understanding of the requirements for future instrumentation. Design of a new instrument is progressing
steadily.
Papers & Publications: None at this time.
305
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STAR Graduate Fellowship Conference
U915620
CHARACTERIZATION OF BEGGIATOA IN BLACK BAND DISEASE
OF SCLERACTINIAN CORALS
T. Shay Viehman
Florida International University
Objectives/Hypotheses; The objective of this research is to characterize the ecological physiology of the
sulfide-oxidizing bacterium Beggiatoa within black band disease of scleractinian corals. Specifically, I will
address the contribution of Beggiatoa to the sulfur and carbon cycles that are generated and maintained by
the microbial members of the black band disease microbial consortium.
Rationale: Black band disease, a contributor to coral death and coral reef degradation, is visually
characterized by a distinct dark band that divides living coral tissue from dead coral skeleton. The black band
migrates horizontally across the living coral tissue, causing tissue death, by an unknown mechanism. This
disease is not caused by a single pathogen, but is a microbial consortium that is comprised of the
sulfide-oxidizing bacterium Beggiatoa, the cyanobacterium Phormidium corallyticum, sulfate-reducing
bacteria such as Desulfovibrio spp., and other microbes. The black band disease microbial community
generates and sustains an active sulfur cycle exactly like those found in laminated microbial mats. Anoxia
(and sulfide) created by the disease microbial community is a known mechanism for coral tissue death.
Although most black band consortium members have been found together in sediment patches on healthy
coral, the stimulus and mechanism behind the assembly of these populations into actively migrating black
band disease is unknown. The genus Beggiatoa consists of Gram negative filamentous, sulfide-oxidizing,
gliding bacteria commonly found at oxygen/sulfide interfaces such as those present in sediments, hot spring
outflows, hydrothermal vents, and hypersaline ponds. Within black band disease, however, Beggiatoa may
not always be positioned at the sulfide-oxygen interface, an unusual behavioral pattern. Black band
Beggiatoa may, in fact, display unique metabolic as well as unique motility properties that may be important
in the horizontal migration of the disease across coral tissue. Increased understanding of the physiology and
environmental cues controlling motility and metabolic patterns of black band Beggiatoa spp are important
to define the functional role of this population within the pathogenic microbial community.
Approa;h= SamPles of black band disease are collected from different infected coral colonies in the Florida
Keys and Caribbean. Black band Beggiatoa spp. are currently in culture in the laboratory, and pure culture
isolations are m progress. Metabolic capabilities, including sulfur and carbon source utilization, of black
band Beggiatoa will be studied using microelectrodes sensitive to pH, oxygen, and sulfide. This approach
allows the investigation of changes in oxygen (and sulfide) flux both /„ vitro in laboratory gradient cultures
and m s*M (underwater) within active black band disease on the coral. The location of Beggiatoa within
vertical sulfide-oxygen gradients in black band disease will be examined with regard to the other members
of the microbial consortium. Investigations of Beggiatoa motilities will also be addressed using light
manipulations. 16s rRNA sequences from black band disease Beggiatoa samples will be compared to those
of known cultures of Beggiatoa found in both marine and freshwater sulfide interface environments.
Status: Beggiatoa spp. obtained from the black band disease consortium are currently in culture on sulfide
ThCe rZ ^f r,~rC C°n,diti0,nS ^thC Iab0rat0ry' Pure Culture isolations ^Beggiatoa are in progress.
The majority of field research and collections, begun in 1999, will be completed in summer 2000; laboratory
studies in progress are expected to be completed by spring 2001.
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Papers & Publications; Viehman, T.S. and Richardson, L.L. 2000. Characterization of Beggiatoa spp.
from the black band disease microbial consortium. 25th Annual Eastern Fish Health Workshop, Special
Workshop on Coral Reef Health and Disease. Plymouth, MA (abstract) p. 57.
Viehman, T.S. 2000. The role of Beggiatoa in black band disease of scleractinian corals. 2nd Annual
Tropical Biology Symposium of Florida International University. Miami, FL (abstract).
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U915190
(RE)CLAIMING THE WATERSHED: PROPERTY LINES, TREATY RIGHTS,
AND COLLABORATIVE NATURAL RESOURCE MANAGEMENT
PLANNING IN RURAL OREGON
Sissel A. Waage
University of California, Berkeley
Objectives/Hypotheses: This research project examines two questions: 1) Why, and under what conditions,
do private landowners and public land users initiate collective action for watershed management planning?
2) How does conflict evolve into collaboration?
Rationale; Analyses of trans-boundary agreements and watershed management efforts have typically
focused on regional scales and institutional issues rather than on the micro-politics of coordinating the
activities of multiple resource users. There has also been little analytical attention to examining the
conditions under which watershed management planning is voluntarily initiated and supported by private
landowners and resource user groups. In addition, few studies have assessed the incentives and disincentives
for private landowners to participate in collaborative resource management planning. Examining these
issues will advance understanding of the conditions under which watershed management can be initiated and
implemented. This research focuses on analyzing a case in which a watershed-based salmon recovery plan
was drafted by an alliance of private landowners, local government officials, and a Native American nation
in the rural Pacific Northwest. Providing an example of watershed management planning from the
ground-up, this study will improve understanding of the potential for, and constraints to, watershed-based
approaches to resource management.
Approach; Using a political ecology analytical approach, I have conducted anthropological, sociological,
economic, and ecological research to examine this collective action effort. During 17 months of residency
in the research community, I interviewed more than 100 people regarding the salmon recovery planning
process. I also observed more than 60 meetings, analyzed aggregate socio-economic and ecological data,
and undertook archival research.
Status; I will complete this study by the fall of 2000.
Papers & Publications; None at this time.
308
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STARGIraduate Fellowship Conference
U915321
PASSIVE AEROSOL SAMPLER TO ESTIMATE LONG-TERM AVERAGE
CONCENTRATIONS AND SIZE DISTRIBUTIONS
Jeff Wagner
University of North Carolina, Chapel Hill
Objectives/Hypotheses; The goal of this work is to develop a miniature, passive aerosol sampler to
estimate Jong-term average concentrations and size distributions. The passive sampler is designed to monitor
indoor or outdoor aerosols over periods of hours to weeks, and has potential utility as a personal sampler.
Rationale; The development of a miniature, passive aerosol sampler can lead to improved PM exposure
assessments.
Approach; Particles collect by gravity, convective diffusion, and inertia in a 1.5 cm-diameter passive
sampler. Scanning electron microscopy and automated image analysis are then used to count and size
collected particles with dp > 0.1 micrometers. Alternatively, more advanced techniques can be used for
ambient-pressure analysis or elemental characterization. The measured particle flux and a particle-size
dependent deposition velocity model are used to calculate the average concentration and size distribution
over the sampling period. A wind tunnel was developed, characterized, and used to test the passive sampler.
The empirical component of the deposition velocity model was determined as a function of particle size, and
precision was assessed using three collocated passive samplers. Next, field tests were conducted in a well-
ventilated occupational environment. Measured friction velocities were less than 0.4 m/s, a range in which
passive sampler performance does not depend on turbulence. Passive sampler results correlated well with
those of eight-stage impactors. Discrepancies between the passive samplers and impactors were attributed
to the small amount of fine particles present, hygroscopic particles, and particle bounce in the impactors.
Status: Ph.D. completed May 2000.
Papers & Publications: Wagner, J. and Leith, D. 2000. Passive aerosol sampler. I: principle of operation.
Aerosol Sci Technol (accepted for publication)
Wagner, J. and Leith, D. 2000. Passive aerosol sampler. II: wind tunnel experiments. Aerosol Sci Technol
(accepted for publication)
Wagner, J. and Leith, D. 2000. Field testing of a passive aerosol sampler. J Aerosol Sci (accepted for
publication)
309
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STAR Graduate Fellowship Conference
U915658
ECOSYSTEM CONSEQUENCES OF EURASIAN WATERMILFOIL (MYRIOPHYLLUM
SPICATUM) INVASION IN LAKE TAHOE, CALIFORNIA-NEVADA
Katey M. Walter
University of California, Davis
Objectives/Hypotheses; This project aims to determine ecosystem effects of the invasion of Eurasian
watermilfoil (Myriophyllum spicatum) at Lake Tahoe. Specific objectives of the study are to: 1) monitor
the occurrence and spread of M spicatum around Lake Tahoe; 2) estimate the potential for infestation of new
areas around the lake; 3) determine whether M. spicatum threatens lake water quality by enhancing the
growth of algae; 4) quantify phosphorus transfer between sediments, water, and algae viaM spicatum; and
5) compare the effects of a native aquatic plant (Elodea sp.) and M. spicatum on lake water quality.
Rationale: Variation in macrophyte biomass and composition, particularly following the invasion of an
exotic species can have important effects on aquatic ecosystems. Although the effects of different environ-
mental conditions on aquatic plants have been extensively examined, the converse effects of invasive
macrophytes on their environment have received less attention. Myriophyllum spicatum a submerged
perennial plant native to Eurasia, is thought to have been introduced to Lake Tahoe about 35 years ago.
Fragments of M. spicatum are easily transported and can establish dense stands in sediments that are
protected from wave action, usually in marina areas. Pressure to find management solutions for this nuisance
weed are strong since M. spicatum interferes with recreation, becomes tangled in boat propellers inhibits
water flow, and crowds out native plant species. The invasion of M spicatum in Lake Tahoe is also of great
concern to those that value the uniquely pristine oligotrophic environment because of its potential todecrease
water quality. By pumping phosphorus from the sediment to feed algae and bacterioplankton in the water,
M. spicatum may contribute to the trend of decreasing water clarity in Lake Tahoe. Despite the importance
of the invasion of this macrophyte in Lake Tahoe, there exists no scientific information on its effect on the
nearshore ecosystem.
T° ™niior the ^currence of M spicatum at Lake Tahoe, aerial and boat surveys have been
^
^^
wrtt ,K ""' kb <*Peri™"«» »«' determine which studies will be
ud™orto rZot f'°"S ? ™de f°r fi"ther m°nit0™8- A"""' »nd monthly surveys will be
contmued for the purpose of creating a CIS map of Eurasian watermilfoil at Lake Tahoe
Papers & Publication.- None at this time.
310
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STAR Graduate Fellowship Conference
U915553
DEVELOPMENT OF A QUANTITATIVE STRUCTURE-ACTIVITY
RELATIONSHIP (QSAR) FOR PREDICTION OF BIODEGRADATION KINETICS
OF POLYCYCLIC AROMATIC HYDROCARBONS
Kris tine H. Wammer
Princeton University
Objectives/Hypotheses: The goal of this work is to use Quantitative Structure-Activity Relationship
(QSAR) analysis to predict biodegradation rates of polycyclic aromatic hydrocarbons and to help elucidate
the relationship between molecular structure characteristics and biodegradation rates.
Rationale: Polycyclic aromatic hydrocarbons (PAHs) are common environmental pollutants that are of
concern because they are suspected carcinogens. One of the major potential fates of PAHs in the subsurface
environment is aerobic biodegradation by microorganisms. Therefore, it is important to elucidate
mechanisms and rates of biodegradation through laboratory work to ultimately indicate behavior in the
natural environment. This is difficult because less soluble PAHs, which tend to be both the most persistent
and most carcinogenic, have aqueous solubilities that fall below detection limits of analytical techniques.
In addition when PAHs exist in complex mixtures it is not possible to measure the biodegradation rates of
aU compounds present. Therefore, there is a need to develop methods for predicting the behavior of
compounds that are difficult to test using relationships derived from the analysis of previously tested
compounds.
Approach; The first step of this research is to explore the potential of developing a PAH biodegradation
QSAR by examination of existing PAH biodegradation data and their correlation with molecular descriptors.
This will be followed by development of a high quality self-consistent database of biodegradation kinetic
parameters for monocyclic and polycyclic aromatic hydrocarbons in aqueous systems, and use of these new
data to develop and validate a QSAR model. Measurements of kinetic parameters will be performed in
experiments with a given substrate as the sole carbon and energy source. These experiments are designed
to control for any confounding physical and chemical processes so accurate information can be obtained
about biodegradation in an aqueous phase without bioavailability constraints. The experiments will be
performed in a series of batch reactors, each of which will be sacrificed to obtain a ^"tntaon
measurement at a point some time from the onset of the experiment. Detection of the Concentration of the
substrate will be done using a high performance liquid chromatograph (HPLC) equipped with a^d ode vny
UV detector and a fluorescence detector; biomass concentration will be measuredJV a todfori ijoton
assay. During the period that these biodegradation experiments are being performed, molecular modehng
techniques w". be examined to provide alternative means of charactemmg ^^^^^
dmgdLript^forQSARmodd^
what the most important molecular characteristics are for determining «>iodcgn«tahon nto^of these
compounds and possibly to determine which steps in the biodegradation process are rate-lim.ting.
Status: Analysisofexistingdatasetsisnearlyfinished. Pr^amtory work in deve^
experiments is almost complete and the experiments will begin in the spring of 2000.
Papers & Publications: None at this time.
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U915389
ENVIRONMENTAL ESTROGENS AND BREAST CANCER THERAPEUTICS:
CHARACTERIZATION OF THE DIVERSE LIGAND BINDING PROPERTIES
OF THE ESTROGEN RECEPTOR
Dana E. Warn
University of Colorado, Boulder
Objectives/Hypotheses: The goal of this project is to develop a structural understanding of how the
estrogen receptor (ER) binds environmental estrogens, natural estrogens and antiestrogens, and to use this
information to develop an assay to predict estrogenic activity. Because of the large number and diversity
of ligands the ER binds, we are interested in developing a scanning technique that provides structural
information.
Rationale; In vertebrates, natural estrogens play a critical role in regulating normal reproduction,
development and growth via their interaction with the ER. But the ER, a member of the nuclear steroid
receptor superfamily, also binds a remarkably diverse set of non-physiologic ligands including
environmental estrogens, phytoestrogens, and antiestrogens. Environmental estrogens are xenobiotic
compounds, such as pesticides, which act as estrogen mimics and alter the reproductive function of wildlife.
The estrogenic behavior of these compounds has proven difficult to predict from their structures; many of
these hormone mimics bear little structural resemblance to natural estrogens. Estrogenic compounds and
natural estrogens bind to the ER and stimulate transcription at genes containing estrogen responsive elements
(ERE). Antiestrogens also bind tightly to the ER; they do not activate transcription. For this reason, partial
antiestrogens such as tamoxifen are currently used to treat hormone-responsive breast cancer The available
structural information on the ER shows that the conformation of the ER is ligand dependent However, the
details of the conformation^ changes that allow the ER to tightly bind such a diverse array of compounds,
and tune the degree of gene activation, are not understood. Developing an assay that provides this
information will assist in identifying estrogenic activity in compounds before they are introduced into the
environment, as well as in identifying compounds with potential therapeutic benefit for treating breast
cancer.
Approach; In the context of the available structural data, we are using multidimensional nuclear magnetic
resonance spectroscopy (NMR) studies of complexes of these compounds with the ligand binding domain
(LED) of the ER to investigate changes that occur on ligand binding. Our strategy of chemical shift mapping
by NMR works as follows: the ER-LBD is prepared 2H, 15N, and 13C isotopically labeled by expression
m£. coli, in media containing D2O,(15NH4)2SO4 as the sole nitrogen source, and 13C glucose as the sole
carbon source. 15N-1H correlation spectra are taken of different ligand-ER-LBD complexes, partial
chemical shift assignments are made, and 15N-1H chemical shift changes are monitored. Chemical shifts
are exquisitely sensitive to changes in the local chemical environment and in conformation, and provide
information on each amino acid in the ER-LBD. Monitoring chemical shift changes allows an assessment
of the ligand dependency of conformational changes, and facilitates the rapid analysis of many complexes.
Status: The expression and purification of 15N labeled wild type ER-LBD has been optimized. The purity
of the ER-LBD has been characterized by SDS-PAGE, native PAGE, and MALDI mass spectrometry.
NMR, circular dichroism (CD), and light scattering studies of the ER-LBD show that the protein is folded,
does not aggregate, and is stable at temperatures useful for NMR studies. Buffer conditions for NMR studies
have been optimized. Several techniques for NMR studies of large proteins have been implemented to
address line width problems due to the large size of the ER-LBD, including a pulse sequence strategy,
transverse relaxation-oPtmiizedsPectroscoPy(TROSY), and deuteration. Expression of deuterated ER-LBD
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has been optimized. NMR data has been collected on multiple ER-LBD-ligand complexes and I5N-1H
chemical shift changes were observed. Chemical shift assignments are in progress.
Papers & Publications: None at this time.
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U915572
EFFECTS OF ENHANCED UV-B RADIATION ON POPLAR
PHYTOCHEMISTRY AND HERBIVORY
Jeffrey M. Warren
Washington State University
Objectives/Hypotheses: This research investigates the direct effects UV-B radiation has on the biochemical
properties of several forest tree species, then correlates those changes with alterations in herbivore growth
rates and feeding preference. The primary study quantifies the growth rate, biomass partitioning,
photosynthesis and foliar chemistry ofPopulus tricocarpa (black cottonwood) grown under OX, 1X, and 2X
ambient UV-B radiation (greenhouse and field trials). In addition, herbivory characteristics of UV-B
irradiated P. tricocarpa foliage by Chrysomela scripta (cottonwood leaf beetle) will be examined. A related
study will analyze the specific flavonoids in P. tricocarpa, Quercus robur, Pinus ponderosa, and
Pseudotsuga menziesii foliage field-grown under IX and 2X ambient modulated UV-B radiation exposure
for quantity and composition.
Rationale; The reaction of extraterrestrial radiation with oxygen in the stratosphere produces ozone, a highly
reactive species that is the primary attenuator of damaging ultraviolet-B (UV-B) radiation. Higher levels of
UV-B radiation reaching the earth's surface could cause extensive, long-term effects on vegetation and all
components of the biosphere. UV-B radiation induced shifts in carbon allocation to various biochemical
pathways may alter plant tissue chemistry and, subsequently, affect plant-pathogen or litter decomposition
processes. Tree response to UV-B radiation appears to be very species specific and could result in
competitive alterations of canopy structure or species composition at the ecosystem level. Tissue payability
may be altered with changes in protein-binding tannins or other phenolic compounds. Additionally, the
nutritional value of the tissue or the ratios of available carbohydrates to key elements could change under
altered UV-B radiation levels. Qualitative composition of flavonoids and other metabolites may also be
affected by UV-B radiation. Few studies have focused on insects or pathogens feeding on foliage of woody
species exposed to higher levels of UV-B radiation, and there have not been any studies with this focus using
tree species important in terrestrial ecosystems.
Approach; Pinus ponderosa, Quercus rubra, Pseudotsuga menziesii, and Populus tricocarpa will be field
grown under ambient and elevated UV-B radiation. Light racks consisting of UVB 313 bulbs (Q-Panel Co.,
OH) connected to a computerized, modulated system supply the supplemental UV-B radiation This system
adjusts individual UV-lamps based on continuous measurement of ambient UV-B radiation using a UV
biometer (Solar Light Co., PA). A spectroradiometer (Optronics Laboratories, FL) and M.M. Caldwell's
1971 weighing function were used to estimate values of biologically effective (BE) UV-B radiation and
adjust system output to maintain a IX or 2X ambient BE UV-B treatment. The cottonwood leaf beetle will
be used as an indicator of UV-B radiation induced changes in P. tricocarpa (90 reps). These organisms will
be applied to the experiment in two ways: 1) in a choice-type or preference test where the third (final) instar
must choose on which tissue to feed (active involvement), or 2) larval growth rates where the first instar is
placed on various tissue types and its progress monitored (passive involvement). Trees will be grown under
the modulated system as well as indoors, with sample leaves selected by leaf plastochron index for the study:
LPI 3 (very immature, preferred) and LPI 5 (less preferred). Leaf biochemical analysis (N, S, C:N,
chlorophylls, flavonoids, photosynthesis, tannins, UV-B absorbing compounds) will be conducted. Leaf disk
area: mass regressions will be used to determine relative larval growth rate per unit leaf area. Larval and
prepupal weight and development time will be used to quantify success on specific tissue
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Status; 1) Indoor UV-B irradiated cottonwood/leaf beetle herbivory study will be completed by August
2000. 2) Outdoor UV-B irradiated cottonwood/leaf beetle herbivory study started May 2000. 3) Flavonoid
biochemistry of Douglas-fir, red oak, black cottonwood and ponderosa pine started May 1999 is proceeding.
Papers & Publications: Warren, J.M., Allen, H.L., and Booker, F.L. 1999. Mineral nutrition, resin flow
and phloem phytochemistry in loblolly pine. Tree Physiology 19: 655-663.
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U915631
THE EFFECTS OF THE COTREATMENTS OF BENZO(A)PYRENE
AND FLUORANTHENE ON THE EXPRESSION AND ACTIVITY
OF CYTOCHROME P450 1A AND ON THE FORMATION OF DNA ADDUCTS
IN THE KILUFISH, FUNDULUS HETEROCLITUS
Deena M. Wassenberg
Duke University
Objectives/Hypotheses: The objective of this work is to find the effects of the polynuclear aromatic
hydrocarbons (PAHs) benzo(a)pyrene (BaP) and fluoranthene (FL), singly and in combination, on the
activity and expression of cytochrome P450 1A (CYP1 A) and on the formation of DNA adducts in Fnndulus
heteroclitus.
Rationale: The induction of CYP1A is often used as a biomarker for exposure to environmental
contaminants, particularly polynuclear aromatic hydrocarbons (PAHs) and halogenated aromatic hydro-
carbons. Ethoxyresorufin O-deethy lase (EROD) activity is one commonly used indicator of C YP1 Aactivity.
Recent in vitro studies have shown that treatment of cells with FL did not induce CYP1A expression.
However, when cells were cotreated with FL and the potent CYP1A inducers 2,3,7,8 tetrachlorodibenzo
-p-dioxm (TCDD) or benzo(k)fluoranthene (BkF), EROD activity was reduced significantly compared to
individually induced responses. DNA adducts are another commonly used biomarker of both PAH exposure
and effect. FL and BaP cotreated cells had increased DNA adduct formation over BaP alone treated cells
(Willett et al., 1999). Similar inhibition of EROD activity and increased adduct formation by co-treatment
offish with BaP and FL in vivo would have implications toward the use of EROD and PAH-DNA adducts
as a biomarkers of contamination in mixed PAH contaminant settings.
Approach; To explore the effects of mixed contaminant exposures in vivo, Fundulus were dosed i.p. with
5 mg/kg BaP, 5 mg/kg BaP + 5 mg/kg FL, 5 mg/kg BaP + 50 mg/kg FL, 5 mg/kg FL, 50 mg/kg FL, or corn
oil. CYP1A mediated EROD activities of liver microsomes from each treatment group were measured.
Additionally, BaP induced microsomes were incubated with 2x10-8 - 2x10-4 M FL and tested for EROD
activity. CYP1A protein expression of liver microsomes was measured by western blot. PAH-DNA adduct
formation will be analyzed for each treatment group by two dimensional thin-layer chromatography of 32P
post labeled nucleotides.
Status: EROD activities were significantly lower in the FL+BaP treated animals than in the BaP-alone
exposed group. Additionally, the inclusion of FL in the EROD activity assay using BaP induced microsomes
decreased EROD activity by up to 82%. In contrast to the in vitro studies, CYP1A protein expression was
somewhat decreased in the co-exposed fish microsomes compared to the BaP-alone induced microsomes.
Because FL concentrations tend to be much higher in the environment than the CYP1A inducers, bioassays
using the EROD assay may be underestimating exposure to PAHs in wildlife.
Papers & Publications; None at this time.
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U915164
DINE BIKEYAH: ENVIRONMENT, CULTURAL IDENTITY,
AND GENDER IN NAVAJO COUNTRY
Marsha L. Weisiger
University of Wisconsin, Madison
Objectives/Hypotheses; In this environmental history, I explore the ways in which livestock pastoralism
shaped the area of the Colorado Plateau known as Dine Bikeyah (Navajo Country). At the heart of my study
is the New Deal effort to halt accelerated soil erosion by drastically reducing the numbers of sheep, goats,
and horses grazing the range. I examine the cultural differences between the Dine (Navajos) and the
scientists with the Soil Conservation Service (SCS), which posed obstacles to developing a workable
range-management program. I further explore whether the range management program introduced by the
SCS led to further degradation of the range.
Rationale; Most studies of grazing in the Southwest have focused on the desert grasslands of the
southernmost part of the region, rather than the cold deserts of the Colorado Plateau, and few have looked
at changes over time. Furthermore, most scholars have assumed that the range has been overgrazed, without
examining the issue in its historical context. Navajo Country provides an opportunity to explore ecological
change in a semi-arid shrubland and examine the unintended effects of well-meaning land-use decisions.
Just as importantly, this history provides a case study of the environmental problems that arise when
conservationists impose culturally-embedded policies on other cultures.
Approach: I focus on cultural ideas while reconstructing a detailed picture of the ecological changes
wrought by grazing to create a richly textured picture of this region of mesas and canyons. Specifically, I
refocus the way we think about Dine history by looking through the lens of a matricentered society and
exploring the implications for women posed by changes in the pastoral economy. Moreover, I scrutinize the
environmental effects of the federal land-management program itself and examine the hypothesis offered
by Dine observers that the disruption of transhumant patterns may be at least partly to blame for the degraded
condition of the range today. I base my analysis on ethnographic studies and field notes, oral histories and
published oral traditions, government records, range studies, published archeological reports, ecological
theory, and anthropological theories. I also examined the Dine range during the severe drought of 1996 and
the unusually rainy season of 1997 to understand what the land itself might tell us about the history of the
area.
Status: I am in the process of completing my dissertation, which I will defend in August 2000.
Papers & Publications; Sheep is life: land use, environment, and identity in Navajo country. Paper pre-
sented at the annual meeting of the Western History Association, St. Paul, MN, October 1997.
Contested stories of the land: federal range experts, Navajos, and livestock grazing 1890-1940. Paper
presentedatthebiennialmeetingoftheAmerican Society for Environmental History, Baltimore, MD, March
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U915320
SMOG CHECK: A CASE STUDY IN ENVIRONMENTAL DECISION MAKING
Louise L. Wells
University of California, Berkeley
Objectives/Hypotheses; This work builds on a inter-disciplinary body of literature that explores the
sources and types of uncertainty that can be important in an environmental decision making process.
Through my research, I am hoping to combine quantitative and qualitative accounts of uncertainty as it
relates to environmental decision making in order to: begin to illustrate what types of uncertainty are
important, how relevant types of uncertainty can be represented to decision makers, and technical
information can be presented to facilitate informed, inclusive environmental decision making.
Rationale; Current decision making methods are inadequate for incorporating multiple parties and value
structures in the decision making process. Therefore, this process cannot adequately reflect the diverse
cultural, social, and institutional positions that are part of most environmental decisions. As environmental
decisions are often scientifically based (or driven), this research focuses uncertainty at the science-policy
interface as a means of understanding the dynamics of the decision making process.
Approach; I am carrying out this research using a case study methodology. In the first case study, I am
examining California's vehicle inspection and maintenance program, Smog Check. Specifically I am
examining the analytical and discursive roles of science and uncertainty in the design and evaluation of
California s program. This case incorporates a quantitative and qualitative analysis of uncertainty with
m-depth, semi-structured interviews and an archival analysis of policy-relevant literature This case study
begins with a series of interviews with different policy actors and an analysis of the technical information
hat informs the decision process. Interviews with scientists and other policy actors are used to determine
the role of uncertainty in forming arguments and supporting agendas in the policy processes The interview
data is supplemented by an analysis of the policy-relevant documents. This data is being used to construct
a narrative account of the role of technical information in the decision process and to illustrate what types
of uncertainty are important. This narrative account is then supplemented through an analysis of the tech-
nical information that is available to decision makers.
Status: The preliminary theoretical background for this research has been developed I have completed the
first stage of my interviews and I am in the process of conducting the archival analysis for my Smog Check
case study. I am writing up my preliminary results and will conduct my second round of interviews in
summer 2000. As this case study progresses, I will be selecting my second case study and beginning field
work (late summer 2000). & &
Papers & Publications; Wells, L.L. and Kastenberg, W.E. 1999. Uncertainty at the science-policy inter-
face: a tool for decision making? Society for Risk Analysis-Europe, Rotterdam, Netherlands October 1999.
(published in proceedings)
Wells, L.L. and Kastenberg, W.E. 1998. Merging technical and institutional issues in environmental
decision making. Presented at the Society for Risk Analysis Annual Meeting, Phoenix, AZ, December 6-9,
±eHTptAerM^WM 't98; InCOrP°rating institutional issues in environmental decision
. Presented at PSAM 4. New York, NY, September 13-18, 1998. Paper in- Probabilistic Safety
Assessment and Management. London: Springer, 3-1635-1640 Probabilistic Safety
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U915306
URBAN REDEVELOPMENT: ASSESSING LEGAL
RIGHTS AND RESPONSIBILITIES
Hope S. Whitney
University of California, Berkeley
Objectives/Hypotheses; To examine current policies promoting redevelopment of polluted, urban land—
so-called"brownfields"—and to investigate how legal, administrative, and community decisions and actions
that limit developers' liability work to encourage or discourage such redevelopment.
Rationale: When deciding whether to build on a brownfield or a non-polluted, urban site, developers have
practical considerations. They want to know if they will incur costs waiting for the project to move forward,
or whether they should risk future costs resulting from liability for the polluted site. The legal liability issues
govern whether they decide to proceed with development of the brownfield and whether creditors will loan
them the money to do so.
The same legal liability issues frame legislative and administrative policy decisions. While the public may
desire urban land to be put to use to prevent suburban sprawl, a system that does little to protect the rights
of third parties (who could be harmed by pollution on a developed brownfield) may be untenable. Efforts
have been made to involve residents of local communities in which brownfields are located, in order to avoid
such conflict. It is important to know what kinds of collaborative processes have been successful in doing
so and what kinds have not.
Approach; My research will investigate the legal aspects of all sides to the debate over brownfield
development liability. First, I will look at how and to what extent developers and creditors rely upon current
"hold harmless" clauses in the nation's "Superfund" law and other statewide and local initiatives aimed at
limiting liability. Second, I will examine the rights of third parties. These parties are obviously not privy
to agreements limiting liability for brownfields, but they still have the potential to be harmed by development
of such property and to be harmed if less than full clean-up is permitted. Third, I will offer examples from
the San Francisco bay area in order to provide real world illustrations of these competing policies in action
and to show how community involvement in these issues affects outcomes.
Status: Research into the basic legal aspects of tort, contract and property law has begun. Currently, I am
examining urban development goals and the structure of land-use controls in the brownfield development
process. In addition, I have studied examples from the city of Oakland and East Palo Alto, in order to
explain the role of collaboration and community partnerships in brownfield redevelopment.
Papers & Publications; None at this time.
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U915157
SEED DISPERSAL AND SEED PREDATION IN ACACIA LIGULATA: THE ROLE
OF PLANT-ANIMAL INTERACTIONS IN MAINTAINING
WITHIN-POPULATION GENETIC DIVERSITY
Kenneth D. Whitney
University of California, Davis
Objectives/Hypotheses; In order to understand how ecological processes function to maintain genetic
diversity in a model field system,! am asking the following question: How do plant-animal interactions such
as seed dispersal and seed predation act to maintain the seed polymorphism in the Australian shrub Acacia
ligulata'?
Rationale; Genetic diversity is currently in decline at many different scales, from the ecosystem level to
the population level. While some causes are clear (e.g., anthropogenic species extinctions directly decrease
genetic diversity at the ecosystem level), others causes are not so apparent. If we wish to protect biological
diversity, we need a better understanding of the ecological and evolutionary processes that naturally produce
and maintain genetic diversity. Roles for certain processes have been demonstrated; for example, divergence
in food plant traits has been shown to contribute to genetic diversity in the African finch Pyrenestes ostrinus
(Smith 1993). However, despite the fact that they are ubiquitous processes, little is known about the effects
of seed dispersal and seed predation on genetic diversity of plant populations.
Approach; Natural populations with detectable polymorphisms, particularly those in which the poly-
morphic characters are under selection, can provide insights into diversity maintenance processes that are
not available from a laboratory setting. Acacia ligulata, a shrub of the Australian arid zone, provides such
a system. It is characterized by a seed polymorphism, in which some individuals produce seeds with a
yellow aril (the food body attractive to animal dispersers) while other individuals produce seeds with a red
aril. No other apparent physical differences distinguish the two morphs, and both morphs co-occur within
local populations, often growing side-by-side. Aril color, which preliminary evidence suggests is genetically
determined, thus serves as a marker indicating the presence of within-population genetic diversity.
Under fluctuating selection models of polymorphism maintenance, theory requires that selection acts
differentially on the morphs, so that each morph is favored in some places and/or times. In Kinchega
National Park, NSW, I am focusing on the conditions under which seed dispersal and seed predation provide
advantages for one A. ligulata morph over the other in four different populations. Via modeling, I will
examine whether these processes are sufficient to maintain the aril-color polymorphism in the species.
Breeding experiments to address the genetic basis of aril color are underway; 750 progeny of 26 crosses are
being grown in the greenhouse. The field results point to predation as the stronger agent of selection: insect
predators such as stinkbugs, wasps, and weevils drastically reduce seed production, and do so in a variable
way. In 1998, yellow morphs produced an average of 43% more seeds than red morphs, but in 1999 they
produced 24% less (ANOVA, p<0.05 in both cases). This variable pattern will continue to be documented
in the 2000 field season, and the interaction between insect abundance and performance, morph chemistry,
and seed production will be investigated further.
Status; My third and final field season will take place from September 2000 - February 2001. I expect to
complete the project by December 2001.
Papers & Publications; None at this time.
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U915410
A STUDY OF THE ENVIRONMENTAL JUSTICE ISSUES ASSOCIATED
WITH THE GROWING SWINE INDUSTRY IN MISSISSIPPI
Sacoby M, Wilson
University of North Carolina, Chapel Hill
Objectives/Hypotheses: To examine the environmental justice issues associated with the growth of the
swine industry in Mississippi. The main goal of the study is to analyze the correlation between the location
of swine facilities in Mississippi and the possible disproportional impact on traditionally disadvantaged
socioeconomic groups due to distributional inequities in the siting of the swine operations.
Rationale: Across the nation, there has been a tremendous increase in the number of industrial hog
operations and a decrease in the number of family farms. These operations have thousands of hogs confined
in a small area that produce large amounts of waste that can lead to air and water quality degradation. In the
state of Mississippi, the number of large-scale hog operations has risen from zero to sixty in just the past 10
years. The current explosive growth in intensive swine operations may lead to a disproportionate burden
of environmental externalities and health risks on certain socioeconomic groups in the state. In addition,
Northeastern Mississippi citizens have complained about the pollution and resulting health problems and
have taken suit against the hog industry in the state. The aforementioned are the impetus for this project
whose main purpose is to evaluate the geographic distributions and prevalence of the operations in proximity
to minority, low-income, and low education communities.
Approach: The study utilizes Arcview 3.1, a Geographic Information Systems (GIS) software program and
statistical packages, to spatially analyze and determine if the presence and activities of these swine
operations disproportionately affect predominately non-white, Jow education, and low-income com-
munities. For my research, socioeconomic Information for the state of Mississippi was taken from the 1990
Census primarily the STF3A summary tape file, which contains various geodemographic data for each
census block group. The geographic coordinates and other information on the industrial hog operations were
extracted from a database compiled by the Mississippi Department of Environmental Quality.
The first analysis consists of a comparison of means for the socioeconomic variables between census block
groups with swine operations and those census block groups without swine operations. The second analysis
consists of a binomial logistic regression, regressing the dependent variable, whether or not a census block
group had a swine operation against the independent socioeconomic variables. The final analysis will
calculate the prevalence of hog operations in block groups for each socioeconomic variable by determining
the ratio of the number of operations per block group among block groups in the higher quiables as
compared to the lowest qumtiles. The above analyses will be performed for the entire state and for the
counties that have at least one industrial hog operation.
Status: The research is almost complete. I am currently performing data analyses and have completed some
oTthTGIS spatial maps. Preliminary data analysis and crude prevalence ratios show that there are
distributional inequitiesforthefollowingsocioeconom
school graduates, percent families in poverty, and percent people in poverty. I expect to be finished by July
2000.
Papers & Publications? None at this time.
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U915654
ECOLOGICAL AND EVOLUTIONARY CONSTRAINTS TO HERBIVORE RESISTANCE
IN A NATIVE PLANT-MULTIPLE HERBIVORE COMMUNITY
Michael J. Wise
Duke University
Objectives/Hypotheses: To identify constraints on the evolution of resistance to herbivory in natural plant
populations. Specifically, I am investigating whether a consideration of an entire community of herbivores
will illuminate potential constraints that would not be apparent from the traditional concentration on just one
focal herbivore species.
Rationale: Due to both the ecological prominence and economic impact of insect herbivory, a great deal
of theoretical and empirical research has been directed toward understanding the evolution of resistance to
herbivory in plants. Despite this attention, it is still not generally clear why plants are not better able to
defend themselves against herbivory. It is clear that herbivore damage is usually detrimental to plant fitness.
Furthermore, there is accumulating evidence that genetic variation in resistance is quite common in natural
plant populations. Therefore, the expectation from population genetics is for plants to evolve toward
complete resistance, at least until the genetic variation is exhausted. Most attempts to resolve the paradox
of incomplete resistance in the presence of genetic variation for resistance have invoked allocation costs, or
tradeoffs between resources used for resistance and other plant functions, such as growth and reproduction.
However, most experiments have failed to find this sort of tradeoff. Therefore, the question of what
ecological and evolutionary factors may be acting to constrain the evolution of resistance remains
unresolved. The thesis of my research is that novel constraints on resistance emerge with a consideration
of more than one herbivore species. These constraints include genetic correlations in resistance to different
herbivores, ecological interactions among the herbivores, non-additivity of the combined impact of multiple
herbivores, and spatial/temporal variation in herbivore community structure.
Approach: This research focuses on the native herbaceous weed horsenettle (Solanum carolinense,
Solanaceae) and its community of insect herbivores. I have been observing four populations of horsenettle
to characterize differences in the composition of the herbivore communities. In 1997, roots of 30 genetic
individuals (genets) were collected from each population, and clones propagated from these individuals will
serve as the subjects of controlled experiments investigating constraints on the evolution of resistance. In
the summer of 2000, a field experiment will be performed to determine the separate and combined effects
of floral and foliar herbivores on plant fitness. Non-additivity of fitness impact by these two types of
herbivores may alter the pattern of selection on resistance in such a way that increased resistance is not
favored. An additional field study will investigate competitive interactions among herbivores in this
community that may interfere with potential selection acting on genetic variation for resistance to given
herbivores. In the summer of 2001, a large field experiment will be performed in which approximately 15
clonal individuals from 44 genets will be randomly transplanted into an old-field, and herbivory and fitness
measurements will be taken on the plants until the end of the growing season. Genetic variation for
resistance to each species, and covariance for resistance among species, will be calculated, and regression
techniques will be used to characterize the natural selection (if any) acting on resistance in the experimental
population.
Sjalus: I have collected 3 years of data on the herbivore community composition of horsenettle in four
fields A severe drought last summer has caused a delay in the experiments. Currently, I plan to have two
more field seasons, with the main field experiment finishing in the fall of 2001
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Papers & Publications; Wise, M.J. and Sacchi, C.F. 1996. Impact of two specialist insect herbivores on
reproduction of horse nettle, Solanum carolinense. Oecologia 108:328-337.
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U915595
CATASTROPHE, UNCERTAINTY, AND THE COSTS
OF CLIMATE CHANGE DAMAGE
Evelyn L. Wright
Rensselaer Polytechnic Institute
Objectives/Hypotheses: This project will explore and develop methods for incorporating the possibility
of catastrophic consequences into the economic analysis of potential climate change damages. The current
state of scientific knowledge concerning several identified potential catastrophes will be examined, and
economically relevant features will be extracted.
Rationale: The question of how much society should spend to slow global climate change has primarily
been addressed through cost-benefit analysis, where the policy "benefits" are the avoided climate change
damages which would otherwise have taken place. So far, most such analyses have neglected the possibility
of catastrophic consequences, such as dramatic sea level rise, changes in global ocean circulation, and the
release of currently frozen stocks of methane. But, it is precisely these catastrophic events that have captured
the public imagination and appear to be influencing current attempts to negotiate international protocols that
far exceed the policies recommended by most economists.
These catastrophic events have been neglected in economic analyses for two reasons. First, not enough work
has been done to make natural scientific information about the systems involved available to economists.
Second, economists have assumed that all of these possible events can be modeled as very low probability,
very high consequence events, which are extremely difficult to analyze. In fact, different potential
catastrophes have very different probability and consequence profiles, and enough scientific information
exists to at least inform economic analysis.
Approach: The natural scientific literature on several different potential climate catastrophes will be
reviewed, and the state of the knowledge concerning their probability and consequence profiles will be
analyzed. One particular event—the possibility of changes in global ocean circulation—will be analyzed in
particular detail, with a focus on the consequences for the degree of climate variability. The effects of
changes in variability on economic costs and the potential for economic adaptation to climate change will
be analyzed using Bayesian learning and option value models.
Stalus: The literature review is nearing completion, and mathematical techniques for the analysis of
variability and adaptation are being explored.
Papers & Publications; Wright, E.L. and Erickson, J.D. Catastrophe and uncertainty in costing climate
change damage. To be presented at the annual meeting of the Western Economic Association International,
Vancouver, B.C., June 30-July 3,2000.
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U915588
PROTOCOL FOR CRYPTOSPORIDIUM RISK COMMUNICATION
FOR DRINKING WATER UTILITIES
Felicia Wu
Carnegie Mellon University
Objectives/Hypotheses; This research aims to improve methods by which water utilities communicate the
risk of Cryptosporidium to the public, accounting for current levels of knowledge and available options for
risk management, so that consumers can make informed decisions regarding their drinking water.
Rationale: Cryptosporidium is among the most prominent drinking water problems in the United States
today, with significant new regulations aimed at limiting the risk of cryptosporidiosis. The regulations
include requirements to communicate Cryptosporidium risk to the public, so that they can make better-
informed choices about their water in a contamination event. To communicate in an effective way,
institutions must first understand the public's knowledge, misconceptions, attitudes, and potential actions
regarding the risk.
Approach: This study employs the mental models strategy to determine lay people's current understanding
of'Cryptosporidium. An analytical expert model was first created, linking concepts associated with water
contamination, communication, and resulting health effects. Model parameters are based upon previous
cryptosporidiosis outbreaks. Next, an elicitation protocol was created and 48 residents were interviewed in
the Pittsburgh region. Their beliefs were mapped into the expert model, gaps and misconceptions were
identified, and statistical analyses were done relating knowledge, attitudes, and actions to different
demographic factors. These results will help in the creation of a communication instrument (e.g., a web page
or brochure) on Cryptosporidium risk, focused on what people need to learn.
Status: The expert model has been created and the interviews have been conducted. The model shows that
if water utilities are not immediately able to remedy their treatment methods, communication to the public
becomes crucial. Preliminary statistical results were obtained, showing that persons with HIV and higher
education level are ra ore I ike ly to have greater knowledge of Cryptosporidium and other drinking water risks.
(There was no significant difference by gender, age, or township.) The results will be further analyzed, and
a communication instrument will be revised based on the findings.
Papers & Publications; Gasman, E., Fischhoff, B., Palmgren, C., Small, M., and Wu, F. An integrated
temporal risk model of a arinking waterborne cryptosporidiosis outbreak. Risk Analysis: accepted for
publication April 6,2000.
Wu, F., Gasman, E., Fischhoff, B., Palmgren, C., and Small, M. The Cryptosporidium risk: what people
need to know, (in preparation)
Wu, F., Gasman, E., Fischhoff, B., Palmgren, C., and Small, M. Content, form, and accessibility of com-
munication instruments on Cryptosporidium.
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U915555
WATER QUALITY IMPACTS OF RIPARIAN BUFFERS
Theresa M. Wynn
Virginia Polytechnic Institute and State University
Objectives/Hypotheses; The objectives of this research are to compare the effectiveness of forested and
grassed riparian buffers in reducing sediment in stormwater runoff, to determine the relative contribution
of channel erosion to total sediment yield in small watersheds with forested and grassed riparian buffers, and
to develop a methodology that can be used to evaluate and predict water quality improvements from riparian
buffers at the watershed scale.
Rationale; Riparian buffers have recently been promoted as a best management practice for water quality
improvement and stream restoration. While it is well recognized that riparian buffers are effective filters
of non-point source pollution under many conditions, the role of vegetation type in streambank stability and
overall watershed sediment yield is unclear. According to the EPA, nutrients and sediment are the most
important causes of water quality impairment in the United States, with sediments being the primary pollu-
tant for rivers. As states are required to develop management plans with Total Maximum Daily Loads for
listed impaired waters, there will be a need to quantify all significant sources of sediment within watersheds
and to determine effective controls. Information is needed on the effects of riparian buffers on channel
erosion and overall watershed sediment yield in small watersheds.
Approach; Two sites in two or three small watersheds will be studied to evaluate the impacts of riparian
buffers on water quality. The sites will be intensively studied to quantify sediment concentrations in storm
runoff and the effects of vegetation type on streambank stability. One site will be a predominately grass
buffer and the other site will be a predominately forested buffer. To completely quantify watershed sediment
yield, suspended sediment and bedload will be sampled instream and topographic surveys of the stream
channels will be conducted. Various statistical procedures will be used to analyze the collected data and to
evaluate the impact of buffer zones on streambank erosion and sediment yield.
Status: Sites are currently being identified and field studies should be started this summer.
Papers & Publications; None at this time.
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U915567
SITE SPECIFIC OXIDATIONS OF ORGANIC COMPOUNDS IN WATER
Jerry C. Yang
Columbia University
Objectives/Hypotheses: Enzymes are remarkable molecules due to their ability to catalyze chemical
transformations with great efficiency. They can mediate energetically unfavorable reactions with high
specificity and very few mistakes. We wish to develop biomimetic catalysts that imitate enzymes, which
would greatly aid the synthesis of organic substances such as Pharmaceuticals due to their high selectivity,
good turnover, and high catalytic rate. Furthermore, developing such catalysts that can operate in water
would be appealing due to its environmentally benign nature as a solvent.
Rationale; An important example of a system we wish to imitate is the oxidative degradation of cholesterol
in biological systems, which is a vital process leading to the formation of many chemical intermediates such
as the steroid hormones'. These enzyme-mediated reactions are dependent on highly site-selective
hydroxylations on the side chain and steroid backbone of cholesterol. Our group is interested in developing
novel synthetic methods of functionalizing steroids with high regio- and stereo-selectivity in order to gain
access to some of these cholesterol degradative products, which are currently only available through the
wasteful process of microbial fermentation.
Approach; The first stage of my project entailed development of a catalyst that could perform
hydroxylations on steroids and steroid derivatives with high selectivity and catalytic turnover. The natural
enzymes responsible for such reactions come from the Cytochrome P-450 class of enzymes. These enzymes
contain a heme- protoporphyrin IX prosthetic group acting as the functional core that delivers a hydroxyl
group to a hydrophibically bound substrate. Since metalloporphyrins have been shown to perform oxidation
reactions in both enzymatic and non-enzymatic systems2, we chose to design a catalyst using these readily
available compounds as our functional core. We then attached one to four cyclodextrins3 to the porphyrm
scaffold producing a hydrophobic binding pocket that could selectively hold substrates in a specific
geometric position to deliver a hydroxyl group to a single site4.
' Steroid Hormone Synthesis. 1991. Encyclopedia of Human Biology, Vol. 7, Academic Press, San
Francisco.
2 Groves, J., McClusky, G., White, R., and Coon, M. 1978. Biochemical and Biophysical Research
Communications 81; 154-160.
3 For a good review on Cyclodextrins see: Chem Rev 1998, Vol. 98, No. 5.
4 Breslow, R., Zhang, X., and Huang, Y. 1997. Jour Am Chem Soc 119;4535-36.
status; We have achieved our initial goal of demonstrating one can use the beneficial driving forces of
water to perform energetically unfavorable organic transformations. Some of these results are described in
a series of publications5 and others are in preparation.
5 Breslow,R., Huang, Y., Zhang, X., and Yang, J. 1997. Proc Natl Acad Sci USA 94; 11156-58.
Papers & Publications; Breslow, R., Gabriele, B., and Yang, J. 1998. Tetrahedron Letters 39;2887-90.
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Yang, J., Weinberg, R., and Breslow, R. 2000. Chemical Communications, pp. 531-532.
Yang, J. and Breslow, R. Angewandte Chemie, International Edition (in press)
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U915598
TIBET'S ECONOMIC REFORM: GREENHOUSE AGRICULTURE
AND A HEGEMONY OF TIBETAN INDOLENCE
Emily T. Yeh
University of California, Berkeley
Objectives/Hypotheses: The deepening of economic reforms across China since 1992 has dramatically
changed the landscape of peri-urban Lhasa, capital of the Tibet Autonomous Region. In particular, Han
Chinese migrants have set up large numbers of greenhouses for irrigated vegetable growing on rented land
previously devoted to barley cultivation, provoking complaints by Tibetans, both about the rapid influx of
Han migrants and about the migrants' extensive use of chemical fertilizers. Despite the lucrative nature of
the vegetable market, few, if any, Tibetan farmers are engaged in the production of these commodities. A
trope of Tibetan indolence, articulated not only through the state's development discourse and by Chinese
migrants, but also by Tibetans themselves, is cited as the explanation for Tibetan non-participation in this
and other new economic opportunities. My doctoral dissertation research will use the phenomenon of
greenhouse agriculture as a lens through which to examine the effects of post-socialist economic transition
on land use; identity; and the operation of hegemony in everyday life in Tibet. The research will be guided
by three primary questions: 1) How have land use and agricultural practices changed in peri-urban Lhasa as
a result of internal migration, a hybridization of property rights, and intensified commercialization brought
about by national economic reforms across China? 2) Why do Tibetan farmers and Han migrants engage
in the land use and agricultural practices that they do? 3) How and why is the hegemonic discourse about
Tibetans being "too lazy" to engage in greenhouse agriculture produced and maintained?
Rationale; The need to understand the local unintended consequences of economic reform, particularly in
(politically, socially, geographically) marginalized areas; to not just assume that effects of economic reform
are uniform across states. To understand land use/land cover change in very important ecological system
(one-third of world's population lives along rivers originating on Tibetan plateau, Tibetan plateau has ma-
jor climate regulation functions, etc.). An analysis that draws on both political economy and cultural politics
to examine how the material and symbolic are mutually constitutive of each other.
Approach: To address these questions, I will conduct an in-depth, year-long ethnography of three villages
in peri-urban Tibet. Through an engagement with literatures on political ecology, development, landscape
and identity and cultural Marxist reinterpretations of "hegemony," I will explore the ways in which
categories of work and landscape are culturally constituted for Tibetan farmers as well as Han Chinese
migrants.
tatus: I will begin the fieldwork component for this dissertation research around August or September
2000.
Papers A Publications; Yeh, E.T. 2000. Forest claims, conflicts and commodification: the political eco-
logy of Tibetan mushroom harvesting villages in Yunnan province, China. The China Quarterly. Vol 161,
pp. 264-278.
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STAR Graduate Fellowship Conference
U915396
LIQUID PHASE MASS TRANSFER IN SPRAY CONTACTORS
Norman K. Yeh
The University of Texas, Austin
Objectives/Hypotheses; Measure the liquid phase mass transfer in sprays for gas-liquid contacting.
Investigate how the mass transfer rate varies with distance from the nozzle and nozzle pressure.
Rationale: Limestone slurry scrubbing is the dominant method of removing sulfur dioxide (SO2) from the
flue gas of coal-fired power plants, and spray absorbers are used in the majority of these applications. The
rate of absorption may be gas or liquid film controlled, depending on where most of the resistance to mass
transfer occurs. Measurements of the gas phase mass transfer coefficients agree well with theoretical
predictions, and the reactions occurring in the liquid phase have been studied extensively. However, the
liquid phase mass transfer coefficients do not agree with models very well, and mass transfer in limestone
slurry scrubbing is believed to be primarily liquid film controlled. In addition, the mass transfer coefficient
is expected to decrease with distance from the nozzle, but this hypothesis needs to be tested quantitatively.
Approach; Mass transfer coefficients in drops are strong functions of drop size and drop formation.
Therefore, the drop sizes and dynamic behavior of drops in spray scrubbing will be reproduced with various
nozzle sizes and types. Working with a commercial scale nozzle provides several challenges, including high
liquid flowrates and drop velocities. An experimental column has been constructed to sample only a small
fraction of the total spray, and a sample collection device has been developed to minimize mass transfer
during collection. The desorption of carbon dioxide (CO2) in an air-water system is used to determine the
liquid phase mass transfer, since the low solubility of CO2 in water tends to favor liquid phase control of the
mass transfer. CO2 gas is sparged into the feed piping upstream of the nozzle so that the gas may be
dissolved before reaching the nozzle. Liquid samples are collected and analyzed to obtain CO2 concentration
as a function of distance from the nozzle. Using the contact time and drop size distribution, mass transfer
coefficients may be calculated from the observed CO2 concentrations in the spray. This procedure should
allow the effects of nozzle selection, nozzle spacing, and operating pressure on the mass transfer coefficient
to be quantified.
status: Preliminary data for the number of liquid phase transfer units have been collected for one
commercial scale nozzle. The sampling and CO2 analysis methods have been refined to minimize losses of
CO2 during and after sample collection. The mass transfer during sample collection has been characterized
as a function of drop velocity. The amount of mass transfer in the spray is calculated by subtracting the
sampler mass transfer from the measured mass transfer performance.
Papers & Publications: None at this time.
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U915538
UNDERSTANDING COMMUNITY AND ECOSYSTEM RESPONSES
TO INTERACTING GLOBAL CHANGES
Erika S. Zavaleta
Stanford University
Objectives/Hypotheses: The goals of this research are to: 1) understand the impacts of co-occurring
climate and atmospheric changes on natural plant communities; 2) examine the long-term implications of
global change-driven community changes for ecosystem processes, including carbon, nutrient, and
hydrological cycles and productivity; and 3) develop a general framework for predicting the community and
ecosystem responses to climate and atmospheric changes.
Rationale; Natural systems throughout the world are experiencing the effects of many, simultaneously
occurring global changes. Experiments to predict the nature of ecosystem responses to environmental
stresses such as warming, rising atmospheric CO2, and nitrogen deposition have generally examined only
one or two global change factors at a time. The possibility of nonlinear or threshold responses in natural
systems subjected to multiple global changes calls for studies that investigate the impacts of a suite of global
changes on natural ecosystems. In order for the results of global change experiments to have real-world
relevance, it is also critical that plot-scale, multi-year findings be scaled up spatially and temporally to
predict landscape and decade- to century-scale ecological impacts. By combining medium-term experi-
mental results with observational studies across natural ecosystem gradients and conceptual models, this
research will strengthen ecologists' ability to quantitatively predict community and ecosystem responses to
interacting global changes at societally relevant scales in time and space.
Approach: I am using a combination of experimental approaches to study global change impacts on com-
munity composition and structure in a California grassland-shrub ecosystem. For 2 years, I have worked
with colleagues to monitor overall community composition and biomass responses and the success of
invading shrubs (Baccharis pilularis ssp. consanguine*) in 136 grassland plots subjected to all possible
combinations of four global changes: 2 degrees of warm ing, doubling of pre-industrial levels of atmospheric
CO,, 50% increases in rainfall, and a degree atmospheric nitrogen deposition typical of urban areas To
understand the longer-term ecosystem consequences of the most significant change occurrmg-shrub
invasion of grasslands-I am examining the time course of change in ecosystem properties along an age
gradient of shrub-invaded sites ranging from 4 to 35 years post-invasion.
This summer, I will be completing the field portion of my research and will begin to process and
samples from my final field season. I plan to analyze data and carry out the modeling component
of my research during the 2000-2001 academic year.
A Publications; Chapin, F.S. Ill, Zavaleta, E.S., Eviner, V.T., Naylor, R.L., Vitousek, P.M., Sala,
OE Reynolds, H.L., Hooper, D.U., Mack, M., Diaz, S.E.,Hobbie, S.E., Lavorel, S. 2000. Functional and
societal consequences of changing biotic diversity. Nature (in press)
Zavaleta E S. and Royval, J.R. 2000. Climate change and the susceptibility of U.S. ecosystems to bio-
logical invasions: two cases of expected range expansion. Invited book chapter, National Wildlife
Federation, Schneider, S.H., ed. (in press)
Zavaleta, E.S. 2000. The economic value of controlling an invasive shrub. Ambio (in press)
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Zavaleta,E. 2000. Valuing ecosystem services lost to Tamarix invasion in the United States. Mooney, H.A.
and Hobbs, R.J., eds. Invasive Species in a Changing World. Washington: Island Press, pp, 261-300.
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U915201
ENVIRONMENTAL DEMOCRACY: AN ANALYSIS
OF BROWNFIELDS POLICY MAKING
Amy A. Zeitler
Purdue University
Objectives/Hypotheses; To compare and contrast strong democracy's normative ideals with an empirical
analysis of brownfields policy making. This research explores how process inclusiveness and issue framing
shape struggles over values that determine policy agendas and constrain the possible alternatives for
remedying social and environmental problems.
Rationale: Many green theorists and policy analysts agree that democratizing environmental politics
improves the prospects for environmental protection; yet they fail to explain that there are many ways to be
democratic. In order to preserve biodiversity, safeguard human and ecological health, and promote
sustainability, democratic processes must be participatory, deliberative, and communicative. In this context,
"democracy" is a "theory of influence" referring to the ability of diverse people to define problems, shape
policy agendas, and influence policy formulation, implementation, and evaluation.
Approach; I use three central concepts to explore how policy actors influence public decision-making:
1) participation, 2) framing, and 3) policy design. Participation refers to people attending policy-related
functions, asking questions, offering thoughts and opinions, and generally engaging in the social elements
of public policy making. Framing describes individual perceptions of the values and goals that public
policies should reflect. Policy design translates voices and values into actions and strategies. By focusing
on particular elements of a policy problem, designs reflect which values, concerns, and perspectives were
deemed acceptable and appropriate and whose voices were influential. Each of these concepts appears
separately in the literature. I combine them to build an empirically testable theory of environmental
democracy that I apply to EPA's Northwest Indiana Cities Brownfields Pilot. I use discourse and content
analysis to evaluate data collected through in-depth interviews; participant observation; and NIBRP-related
documents (the pilots' original application materials, work plans, public meeting notes, position papers, fact
sheets, newsletters, newspaper articles, internal memos, annual reports, meeting minutes, workshop
handouts, and press releases).
Status; This project resulted in an 8-chapter dissertation, which I shall defend on June 29,2000.
Papers & Publications; None at this time.
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U915318
OPERATIONAL INDUCED CHANGES IN GEOMEMBRANE
SURFACE TOPOGRAPHY
Tamara E. Zettler
Georgia Institute of Technology
Objectives/Hypotheses; To develop a comprehensive understanding of both shear and strain induced
changes in the surface topography of geomembranes and the subsequent influence on interface strength. The
results will aid in the design of numerous geosynthetic applications including landfill liner and cover
systems.
Rationale; The use of geosynthetics in civil engineering applications is continually increasing. For ex-
ample, both liner and cover systems for landfills are now required by RCRA to be constructed using
alternating layers of geosynthetics and/or natural soil materials. The strength of the interfaces between these
synthetic and natural materials is of significant concern in stability analyses. The goal of this research was
to understand how changes in surface roughness of geomembranes as induced by shear mechanisms or
strains affect the strength of geomembrane versus granular soil interfaces. This will aid in the design of
more efficient interface systems for use in geosynthetic applications as well as improved design of
geomembranes.
Approach; The roughness of the geomembrane is a critical parameter in the strength of the interface.
Previous research has shown the strength mechanism for smooth geomembranes and granular soils to be a
function of sliding and plowing of the particles at the interface. This research quantitatively investigated the
increase in roughness of the membrane as a function of various normal loads and particle angularities. The
amount of plowing was shown to directly impact the interface strength.
In addition, an investigation was conducted to determine the change in roughness of geomembranes as
subjected to strains experienced under normal field operating conditions. When the geomembranes are
strained, the initially rough membranes showed small decreases in roughness. As a result, the interface
strength will be less than anticipated.
Status: This research was completed in December 2000. Results of the research can be found in Zettler
(1999).
Papers & Publications; Zettler, T.E., Kasturi, G., Bhatia, S.K.,, Abdel-Rehman, A.H., and Bakeer, R.
1998. Influence of grid configuration on interface shear strength of soil/grid systems. Proceedings of
Geosynthetics '98: Atlanta, pp. 733-738.
Zettler, T.E. 1999. Operational induced changes in geomembrane surface topography. M.S. Thesis, School
of Civil and Environmental Engineering, Georgia Institute of Technology, 264 pp.
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