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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems


                                        Introduction

Annual Review of EPA STAR Research on:

(1) Regional Scale Stressor Response Models for Environmental Decision-making

(2) Consequences of Global Change for Aquatic Ecosystems: Climate, Land Use, and W Radiation

    The mission of the U.S. Environmental  Protection Agency  (EPA) is to protect, sustain and restore the
health of ecosystems and communities.  To support this mission,  EPA's Office of Research and Development
(ORD) implements a coordinated  research strategy comprised  of in-house research  conducted at its own
Laboratories and  Centers  and extramural research  sponsored by EPA ORD's Science To  Achieve Results
(STAR) Program. STAR awards are made to the academic community and non-profit research organizations
through a highly competitive program of independently peer-reviewed proposals  solicited by the ORD's
National Center for Environmental Research (NCER).

    This  document summarizes research sponsored by two STAR solicitations:  (1) Developing Regional-
Scale Stressor-Response  Models  for  Use  in Environmental  Decision-making,  and  (2) Assessing  the
Consequences of Global Change for Aquatic Ecosystems: Climate, Land Use, and UV Radiation. This research
was funded by the STAR Ecological Research Program1 and the STAR Global Change Research Program2.
The content of this document reflects presentations made  by Principal Investigators at the annual progress
review meeting held in Arlington, Virginia, November 3-4, 2005.

    The 2002 solicitation for Developing Regional-Scale Stressor-Response Models for Use in Environmental
Decision-making  sought  proposals for the development of regional  scale models that could be used to
investigate, simulate and predict interactions of multiple stressors on the health of  aquatic  ecosystems. The
research objective was to  develop the scientific information needed to facilitate state and local implementation
of integrated ecosystem management practices. This document summarizes a portfolio of 11 separate modeling
studies sponsored under this solicitation. The stressors to ecosystems include non-point sources of nutrients
and sediments,  alterations in stream flow due  to development or climate  variability, invasive species,  and
habitat alteration. Modeling techniques include innovative Bayesian statistical models, new approaches to
coupled physical  models, and individual-based models.  These multiple stressor-response models are  being
developed for selected river systems, coastal estuaries, and lakes, and they are being implemented at  scales
from  site-level to entire  watersheds.  Although this  research is  still in progress, in many  instances  the
investigators have already begun working with resource  managers who may ultimately benefit from  the
creation of these new modeling tools.

    The 2001 solicitation Assessing the Consequences of Global Change for Aquatic Ecosystems: Climate,
Land Use,  and UV Radiation sought proposals that contributed  to the scientific literature and  developed
decision support tools designed to  quantitatively and qualitatively relate watershed characteristics to aquatic
ecosystem health and water quality. Principal investigators presented final research results that elucidate:  (1)
the impacts  of climate change  and land use in relation to ultraviolet radiation levels in Rocky Mountain
streams, and the Lehigh and Ontonagon Rivers; and (2) how climate variability, and past, current  and  future
land use practices influence the ecological structure of vegetation and animal communities  relying on playa
lakes  in the Southern Plains.

    For further background on these topics, go to the following Web sites to read  the two Requests for
Applications (RFAs) that resulted in the award of the grants described in this  report:

    http://es.epa.gov/ncer/rfa/archive/grants/02/02regstressor.html

    http://es.epa.gov/ncer/rfa/archive/grants/01/global01.html
           The Office of Research and Development's National Center for Environmental Research

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                     Joint Progress Review for U.S. EPA STAR Grants:  Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
    For more information about the STAR Global Change Program for ecosystems research, contact Bernice
L. Smith at 202-343-9766 (Smith.Bernicel@epa.gov). For information about the  STAR Ecological Research
Program, contact Iris Goodman  at 202-343-9854 (Goodman.Iris(g),epa.gov). Finally, for more information on
all research areas in EPA's STAR program, please go to http://www.epa.gov/ncer.

    The research described  in this report has not been subjected to the Agency's required peer review and
policy review, and does not necessarily reflect the views of the Agency. Therefore, no official  endorsement
should be inferred. Any opinions, findings, conclusions,  or recommendations expressed in this report are not
necessarily those of EPA, but rather those of the investigators who presented their research and other workshop
participants.
  The primary focus of EPA ORD's Ecological Research Program is to:

(1)  Assess the condition of the nation's ecosystems.
(2)  Diagnose the causes of impairments to these ecosystems.
(3)  Forecast how ecosystems respond to existing and emerging ecological stressors.
(4)  Establish methods to set priorities for protecting and restoring impaired ecosystems.
2
  The primary focus of EPA ORD's Global Change Research Program is to improve society's ability to respond and
adapt to future consequences of global change. This entails:

(1)  Improving the scientific capabilities and basis for projecting and evaluating effects and vulnerabilities of global
    change;
(2)  Conducting assessments of the ecological,  human health and socioeconomic risks and opportunities presented
    by global change; and
(3)  Assessing management and adaptation options  to improve society's ability to effectively respond to the risks
    and opportunities presented by global  change.

Assessments of the effects of global change on aquatic ecosystems  (freshwater and coastal) and their services in the
context of other stressors and human dimensions is the focus of the  Ecosystem Focus Area of EPA's Global Change
Research Program.  Linked  aquatic-terrestrial ecosystems also are considered to inform the impact of global change
on aquatic ecosystem functioning and services. EPA's  Global Change Research Program is consistent with the U.S.
Climate Change Science Program (CCSP)  and contributes to the many goals set forth in the CCSP Strategic Plan.
           The Office of Research and Development's National Center for Environmental Research

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                 Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
          Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
   Joint Progress Review for U.S. EPA STAR Grants:  Regional-Scale
 Stressor-Response Models and Consequences of Global Change for
                              Aquatic Ecosystems

                              Sheraton National Hotel
                                 900 S. Orme Street
                                Arlington, VA 22204

                                November 3-4, 2005
                                      AGENDA

This is a Joint Workshop and Progress Review for U.S. EPA STAR Grants on the topics:

       (1) Regional-Scale Stressor-Response Models for Aquatic Ecosystems
       (2) Effects of Climate, Land Use and UV Radiation on Aquatic Ecosystems

*Posters of PI research will be on display both Thursday and Friday

Thursday, November 3, 2005

7:30 - 8:30 a.m.        Registration and Poster Set-Up

8:30 - 9:00 a.m.        Welcome and Introduction
                     Becki Clark, Director Environmental Science Division, U.S. EPA, NCER
                     Joel Scheraga, Ph.D., National Program Director, EPA Global Change
                     Research Program, U.S. EPA
                     Iris Goodman, Ecological Research Program Manager, U.S. EPA, NCER

Session I Theme: Regional-Scale Physical Models for Environmental Decision-Making

9:00 - 9:40 a.m.        Development of Coupled Physical and Ecological Models for Stress-Response
                     Simulations of the Apalachicola Bay
                     Mark Harwell, Ph.D./Hongquing Wang, Ph.D., Florida A&M University

9:40 - 10:20 a.m.      Developing Regional-Scale Stressor Response Models for Managing
                     Eutrophication in Coastal Marine Ecosystem
                     Robert Howarth,  Ph.D., Cornell University

10:20 - 10:35 a.m.      Break (Pis are available to discuss their posters)

10:35 - 11:15 a.m.      A Shallow-Water Coastal Habitat Model for Regional-Scale Evaluation of
                     Management Decisions in the Virginia Province
                     Charles Gallegos, Ph.D., Smithsonian Institution

11:15-11:55 a.m.      Development of a Regional-Scale Model for the Management ofMultiple-
                     Stressors in the Lake Erie Ecosystem
                     Joseph Koonce, Ph.D., Case Western Reserve University
         The Office of Research and Development's National Center for Environmental Research

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                   Joint Progress Review for U.S. EPA STAR Grants:  Regional-Scale
          Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
12:00 noon - 1:15 p.m.  Lunch

Session II Theme:  Regional-Scale Statistical Models for Environmental Decision-Making

1:15 - 1:55 p.m.        Adaptive Implementation Modeling and Monitoring for TMDL Refinement
                       Kenneth Reckhow, Ph.D., Duke University

1:55 - 2:40 p.m.        Bayesian Methods for Regional-Scale Stressor Response Models
                       Conrad Lamon, Ph.D., Duke University

2:40 - 2:55 p.m.        Break (Pis are available to discuss their posters)

2:55 - 3:35 p.m.        Developing a Risk Propagation Model for Estimating Ecological Responses of
                       Streams to Anthropogenic Watershed Stressors and Stream Modification
                       Vladimir Novotny, Ph.D./Elias Manolakos, Ph.D., Northeastern University

3:35 - 4:15 p.m.        Developing Relations Among Human Activities,  Stressors, and Stream
                       Ecosystem Responses and Linkage in Integrated Regional, Multi-Stressor
                       Models
                       Jan Stevenson, Ph.D., Michigan State University


Friday, November 4, 2005

8:30 a.m.               Introduction
                       Bernice  Smith, Ph.D., Global Change (Ecosystems Research) Program Manager,
                       U.S. EPA,NCER

Session III Theme:  Regional-Scale Population Models for Environmental Decision-Making

8:30 - 9:10 a.m.        Effects of Multiple Stressors on Aquatic Communities in the Prairie Pothole
                       Region
                       Patrick Schoff, Ph.D., University of Minnesota-Duluth

9:10 - 9:50 a.m.        Application of Individual-Based Fish Models to  Regional Decision-Making
                       Roland Lamberson, Ph.D., Humboldt State  University

9:50 - 10:20 a.m.       Stressor-Response Modeling of the Interactive Effects of Climate Change and
                       Land Use Patterns  on the Alteration of Coastal Marine Systems by Invasive
                       Species
                       Robert Whitlatch, Ph.D., University of Connecticut

10:20 - 10:35 a.m.      Break (Pis are available to discuss their posters)

Session IV Theme:  Climate, Land Use, and UV Radiation on Aquatic  Ecosystems

10:35 - 11:05 a.m.      Interactive Effects of Climate Change,  Wetlands, and Dissolved Organic
                       Matter on UV Damage to Aquatic Foodwebs
                       Scott Bridgham, Ph.D., University of Oregon
          The Office of Research and Development's National Center for Environmental Research

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                   Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
11:05 - 11:45 a.m.       The Influence of Climate-Induced Alterations in Dissolved Organic Matter on
                        Metal Toxicity and UVRadiation in Rocky Mountain Streams
                        William Clements, Ph.D., Colorado State University

11:45 a.m. - 1:00 p.m.   Lunch

1:00 - 1:40 p.m.         Interactions Among Climate, Humans, and Play a Wetlands on the Southern
                        High Plain
                        Scott McMurry, Ph.D., Texas Tech University

1:40 - 2:20 p.m.         Assessing the Interactive Effects of Land Use, Climate, and UV Radiation on
                        River Ecosystems: Modeling Transparency and the Response of Biota to UVR.
                        Bruce Hargreaves, Ph.D., Lehigh University

2:20 - 2:30 p.m.         Break (Pis are available to discuss their posters)

2:30 - 4:00 p.m.         Discussion Session
                        This informal discussion session provides an  opportunity for STAR grantees and
                        staff of EPA Program Offices, Labs, and Centers to explore opportunities to further
                        advance the research topics presented. The group will  choose the topics to be
                        discussed; preliminary suggestions include:  (1)  ways to share  data, ideas, or
                        modeling methods, and (2) ways to synthesize and communicate research results.
                        To start off the discussion, we will have three  speakers give brief remarks (i.e., 5 -
                        7 minutes):
                        Rochelle Araujo, Ph.D., U.S. EPA, NERL,  ADE; Charles Noss, Ph.D., U.S. EPA,
                        ORD; and Noha Gaber, Ph.D., U.S. EPA, NCER

4:00-4:10 p.m.         Closing Remarks
                        Bernice Smith, Ph.D., Global Change (Ecosystems Research) Program Manager,
                        U.S. EPA, NCER
           The Office of Research and Development's National Center for Environmental Research

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      Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
       Regional-Scale Physical Models
     for Environmental  Decision-Making
The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
    Developing Regional-Scale Stressor-Response Models for Use in
             Environmental  Decision-Making in Apalachicola  Bay

             Mark A. Harwell, Ping Hsieh, Wenrui Huang, Elijah Johnson, Katherine Milla,
                  Hongqing Wang, Kevin Dillon, Glynnis Bugna, and John H. Gentile
                         Environmental Cooperative Science Center (ECSC),
                         Florida A&M University (FAMU), Tallahassee, FL

                                            Abstract

    Florida's Apalachicola Bay is the "last great bay" that is relatively pristine in the United States. The Bay is
one of the nation's major producers of American oysters (Crassostrea virginicd). It is significantly influenced
by freshwater flows from the Apalachicola, Chattahoochee, and Flint River system (ACF), which drains
approximately 60,000 km2 of Georgia, Alabama, and Florida.  Of particular concern are  the  present and
anticipated reductions below the historical freshwater flows from the ACF system, particularly for urban use in
Atlanta and center-pivot irrigation agriculture in Georgia. The valued ecosystem components  (VECs) of the
Apalachicola  Bay ecosystem include oysters, recreational fisheries, salt marshes, and associated aesthetic,
endangered, and recreational species of birds, fish, and invertebrates. Stressors include changes in salinity and
turbidity, sea-level rise, nutrient inputs, tropical storms and hurricanes, and habitat alteration.  Our objectives
are to develop models  that can be used to  evaluate the stress-responses  of the Bay to these natural and
anthropogenic stressors,  and provide scientific support to the  environmental  decision-making  process
following the U.S. Environmental Protection Agency (EPA) ecological risk assessment framework.

    We have been developing a coupled physical and ecological model system to accomplish  our objectives.
The physical models include a 3-D hydrodynamic model (modified from the Princeton Ocean Model [POM]),
a river flow model  (MODBRNCH),  and  a water quality model (EPA  WASP 6)  to simulate  the  current,
transport,  salinity, sediment,  and nutrient regimes  of the Bay.  These  physical models are  being  coupled
through  a Geographic Information System (GIS) framework to  ecological models (i.e., salt marsh, oyster
population, habitat  suitability  and  landscape metrics)  to simulate  effects   of stressors on the  VECs.
Hyperspectral remote sensing data, acquired under separate funding from National Oceanic and Atmospheric
Administration (NOAA), provide information for model calibration and stress responses.

    To date, we have calibrated and validated a 3-D Apalachicola Bay hydrodynamical model  to  examine the
effects of freshwater flow, tide, and current on estuarine salinity. We have developed a salt marsh soil salinity
model to  examine  impacts  of  climate,  tidal  forcing,  soil, vegetation, and  topography  on  soil  salinity
distribution along different elevations in the Atlantic and Gulf of Mexico coastal region. We continued  to
acquire spatially explicit databases for the Bay, including weather data, topography, and  nutrient and salinity
data for 2002-2004. We are now developing an oyster population model for Apalachicola Bay, and acquiring
extensive  existing databases  for oysters in the Bay. Meanwhile,  technical difficulties have developed  in
coupling of the hydrodynamical model with  a water quality model, and in calibration of the  MODBRNCH
model. As a result, we are exploring alternate river and water quality modules for our coupled model system.

    The next steps are  to: (1) complete the linkage  of the 3D  hydrodynamic model to the water quality
module; (2) complete the implementation and calibration of a river flow regime  model; (3) continue the
acquisition of data and implementation in the GIS database; (4) complete the development and calibration  of
the salt marsh ecological/hydrological model; (5) continue  developing and coupling  the oyster population
model with hydrodynamic model;  and (6)  conduct  a  demonstration  ecological risk  assessment  through
development of the test scenarios related to climate change and ACF water management.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Hongqing Wang, who presented for Dr. Mark Harwell

A  One participant asked what unit was used for the suspended sediments concentrations in the model. Dr.
    Wang replied  that it  was milligrams/liter.  These measurements will  be checked  against real data to
    determine if they are correct. The participant commented that he was surprised to see sea grasses  in the
    system with the depth of suspended sediments and asked if there were water clarity measurements. Dr.
    Wang responded that there was monitoring for a number of water quality parameters.

A  One participant stated that he was interested in the use of the Princeton Model and the application  to the
    bay and asked if the project looked at how the grid size of the model affected the predictions of tidal flow.
    Dr. Wang responded that he was not the hydrologist on the project, but the grid size they are using should
    be suitable with some variation.

A  Iris Goodman asked if Dr. Wang has any sense of the relative contribution of tidal and bay influences
    versus the water management in the uplands draining into the bay. Dr. Wang responded that if the river
    location changes, it will affect the salinity and oyster population in the bay.

A  One participant stated that the bay has a strong west to east salinity gradient and 90 percent of the fresh
    water is coming from the Apalachicola River, and asked why there is low salinity in the western part of the
    bay?  Dr. Wang responded that most of the  ocean water  is coming from the eastern part and the  ocean
    current is east to west. The fresh water comes from the river mouth and reduces the salinity.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
  Developing Regional-Scale Stressor Response Models for Managing
                  Eutrophication  in Coastal Marine  Ecosystem

                                          Robert Howarth
                                   Cornell University, Ithaca, NY

                                            Abstract

    Our goals are to: (1) develop a regional-scale  model for analyzing nutrient inputs to coastal ecosystems;
(2)  develop  a model-based  classification scheme  for the comparative  analysis  of the sensitivity of coastal
ecosystems to these nutrient inputs; and (3) develop quantitative approaches for evaluating how other stressors
such as climate change, land-use change, and sediment fluxes interact with nutrient inputs to affect coastal
ecosystems.

    The project has two interacting parts.  First, we  are  developing and testing the Regional Nutrient
Management Model (ReNuMa), a model designed  to be used by managers to evaluate sources of nutrient and
sediment fluxes from regions and large watersheds to coastal marine  ecosystems, and to be responsive to
watershed management practices. We are refining  and modifying this model to increase its effectiveness as a
tool to investigate the interacting effects of climate variability, climate change, and land-use change on fluxes
of water and nutrients from regions  and watersheds. Second, we have developed a nutrient-phytoplankton-
zooplankton  (NPZ) model of estuarine response to  hydrologic forcing and nitrogen loading. We are using this
model with  available data sets  (e.g., National Oceanic  and Atmospheric  Administration and Land-Ocean
Interactions  in the Coastal Zone) on physical and ecological aspects of coastal marine ecosystems towards
evaluating the  sensitivity  of coastal  marine ecosystems to nutrient enrichment, and to predict how  climate
change and other stressors interact with this sensitivity.

    Progress to date includes:  (1) additional analysis of interactions between hydrology and nitrogen fluxes in
16 Northeastern U.S. watersheds; and (2) development and preliminary testing of a watershed-scale regional
nutrient management model (ReNuMa) and the NPZ model of estuarine response to nitrogen loading, which
we  are using to  develop a process-based estuarine  classification scheme. Analysis of the relationship between
climate and Net Anthropogenic Nitrogen Inputs (NANI) to Northeastern U.S. watersheds suggests that 75-80
percent of nitrogen  inputs are retained  or  denitrified in the landscape; those  watersheds with higher
precipitation or discharge export  a  greater fraction of  N inputs in streamflow, possibly  due  to reduced
denitrification.  The ReNuMa model shows  good agreement between observations and  annual simulations of
both streamflow and dissolved inorganic nitrogen at the regional scale, though better parameterizations may be
required for  individual watersheds. The NPZ model suggests that differences between estuarine responses to
point source  and non-point sources of nitrogen may result due to the differences in coupling with hydrology.

    Nutrients are now the  largest pollution  problem in the  United States. This set of tools  will allow
environmental managers to  set priorities for targets in nutrient reduction, by source of nutrient, and among
multiple watersheds  in the context of relative benefit to be achieved in coastal water quality. It also will allow
managers  to explore scenarios for how land-use  change and climate change may interact with plans for
reducing  nutrient pollution. This  project  will fulfill two high  priority recommendations of the National
Research Council (NRC) (2000) report on coastal nutrient pollution.

    The major objectives for the next year include: (1)  further  development  of the watershed model and
preliminary testing in the Upper Susquehanna and other Northeastern U.S. watersheds; (2) further development
and analysis of the dynamics of the NPZ estuarine response model and comparison with available estuarine
datasets; and (3) coupling of the terrestrial and  estuarine response models.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Robert Howarth

A  One participant asked why the coastal plain area was not shown on the graph showing the distribution of
    the 16 watersheds. Dr. Howarth responded they are using the U.S. Geological Survey (USGS) monitoring
    data for the river flux estimates and there are no gauging  stations in that area. There are no USGS water
    quality data further downstream in any of the watersheds closer to the coast. The water that is upstream of
    the gauging  stations  is relatively rural. The  highly industrialized, heavily populated  area,  which also is
    contributing  to nitrogen to the coast, is not included in the analysis. The participant asked if correction
    factors were added. Dr. Howarth responded that in the statistical mass balance approach  they are only
    dealing with the watersheds. He is fairly confident that they can understand, at least in a temperate zone,
    what is going on with human  alteration of nitrogen cycling in relatively rural  areas.  He is not sure that
    when they get into hilly, urbanized areas that the parameters are valid. They have a separate effort funded
    by the Hudson River Foundation where they are trying to do mass balances for the lower Hudson River
    estuary in the New York City  Harbor area. They are using the City of New York water quality data and
    plotting nutrient concentrations versus salinity to determine statistically nutrient input sources versus the
    city. That will give them at least one urban area in the next few years.

A  One participant asked if Dr. Howarth had addressed the role of hydrologic variability in terms of whether
    the wetness of the watersheds is really affecting the amount of nitrogen deposition. Dr.  Howarth responded
    that they are just starting to work on it. They have looked at long-term averages for sinks. There  also is a
    short-term effect of short-term storage and loss,  and they will be looking at the historical data set for this
    data. For the Northeast watersheds,  they have total nitrogen fluxes  on an  annual basis from the 1980s to
    the present. They also have nitrate data for a subset of about seven or eight of the watersheds,  some of
    which go back to 1919.

A  One participant asked if they expected more  contributions from climate change on nitrogen flux to rivers
    in the watershed level compared to human inputs such  as fertilizer use. Dr. Howarth responded that
    climate change affects the nitrogen deposition. On average, most of the nitrogen is not reaching the coast;
    it is going into the landscape  where it is denitrified, and he thinks that it is climatically sensitive. The
    problem will be aggravated where climate change leads to wetter environments. There are places where
    climate change will not make it wetter. Most of the model projections say that the Mississippi River Basin
    will be dryer.

A  One participant commented that there is much data on nitrification.  He asked why there is variability that
    is not understood in nitrification and what the knowledge gap was?  Dr. Howarth responded that there is a
    tremendous amount of data measuring denitrification in well-ends and in low-order streams. There are hot
    spots for denitrification. When you try to scale it beyond the plot scale, there are problems. The issue is of
    the water resonance time and whether the water that is draining off the landscape is really going through or
    under wetlands, or if it  goes through the  wetlands  so  quickly that  it does not  really process for
    denitrification. It is very hard to scale to an entire catchment basin to show how effective the wetlands are
    as a sink.

A  Iris Goodman commented that EPA deals with the problem  of how to best combine insights gained from
    monitoring and insights gained from modeling. Certainly, both have their limitations and there is no right
    answer.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
 A Shallow-Water Coastal Habitat Model for Regional Scale  Evaluation
            of Management  Decisions in the Chesapeake Region

   Charles L. Gallegos, Donald E. Wetter, Thomas E. Jordan, Patrick J. Neale, and J. Patrick Megonigal
                    Smithsonian Environmental Research Center, Edgewater, MD

                                            Abstract

    Management decisions to protect estuaries are being made in the context of unprecedented environmental
changes including rising concentration  of atmospheric C02, increased ultraviolet (UV) radiation, especially the
damaging UV-B, and changes in land use patterns. Interactions between altered rainfall regimes and changes in
land use patterns will have consequences for the delivery of sediments and nutrients to estuaries. Projecting the
effectiveness of management actions must proceed on the basis of predictions from mathematical models,
because experimental manipulations cannot be made on the relevant scales.

    Our modeling efforts focus on shallow tributary embayments and small tidal creeks of Chesapeake Bay,
because the ecological importance of  shallow systems  far exceeds their volumetric contribution to the bay.
The end points for our model will be those indicators  being used as delisting criteria for  Chesapeake Bay,
namely, chlorophyll, water clarity (diffuse attenuation coefficient), and dissolved oxygen.

    Progress has been made on development of a three-compartment subestuary model. The model domain
segments with different volumetric dimension, lying in between boundaries at the mouth and at the head of the
subestuary.  The  watershed is considered to be  an  upstream boundary where multiple stressors, such  as
inorganic nutrients, sediments, and dissolved organic matter,  are discharged.  The downstream boundary is
considered to be the Chesapeake Bay, or a major  tributary, such as the Potomac  or James River.  Each
subestuary segment has  multiple ecological  components  (26  state variables),  including nutrients,  size-
fractionated  phytoplankton (3 size  classes) and zooplankton (3  size classes), and  detritus. Nitrogen and
phosphorus are tracked separately to allow for spatial or temporal changes in the limiting  nutrient (double-
currency system), and light propagation through water column is computed based on empirical bio-optical
algorithms.

    One project objective is to analyze how the geographic variability in physical structure and human use
among the linked watershed-subestuary systems of Chesapeake Bay affects estuarine responses to multiple
stressors. The descriptive  portion  of this task has been completed. We have identified 128 Chesapeake Bay
systems that fit our local watershed-subestuary paradigm and have captured the boundaries of these systems in
a Geographic Information System  (GIS)  database.  Subestuary  areas range  from 0.1-101  km   and  their
associated local watershed areas range from 6-1664 km2,  with the National Land Cover Database land cover
percentages ranging from 6-81 percent forest,  1-64 percent  cropland,  2-38  percent grassland, and 0.3-89
percent developed land. We also  analyzed digital shoreline and  bathymetric data to calculate  a number of
subestuary metrics, including subestuary area and water  volume, mouth width and area of vertical profile,
proportion of shallow water ([ 2 m) area, elongation ratio, fractal dimension, the ratio of subestuary  perimeter
to subestuary area, and ratio of local watershed area to subestuary volume.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Charles Gallegos

A  One participant asked if there was any progress in measuring water clarity or transparency. Dr. Gallegos
    responded that there was a lot of progress in terms of the basic frame of the model. The model will be able
    to do  a good job of predicting the diffuse attenuation coefficient from CDOM, particulate matter, and
    chlorophyll.

A  One participant asked how they were handling the nitrogen versus phosphorus limitation. Dr. Gallegos
    responded that it will be from concentrations in the delivery water plus what is coming out of the
    sediments in relation to  phytoplankton  needs and demands. For phytoplankton, they are running an
    internal pool type of model.  It is one of the things that will be examined in the generalized  sensitivity
    analysis to determine if that level of detail really is needed  to predict the limiting nutrient. It is being
    handled primarily by the sources.

A  One participant asked how sensitive the model is to including the different size classes. Dr. Gallegos
    responded that he did not know how sensitive the model was  to the different size structures. He wants to
    start out with something detailed and see how far down he can simplify it. One of the things that might
    survive is the effect on water  clarity, because that is one place where size makes a difference.

A  One participant asked whether taxonomic composition, which may play a major role in the potential for
    sinks, will be addressed in the model. Dr. Gallegos responded that if they handle it at all, it will be very
    parameterized  in terms of sinking rates versus time from  what  they know about the changes in the
    taxonomic composition. He does not think that attempts to model that explicitly have been very successful.

A  Iris Goodman  commented that 18 metrics have been developed on the 128 systems. She asked if these
    metrics would be sufficient to parameterize the model in all the needed ways or would they need to add
    more  parameters.  She was  interested in the notion  of how they are working  their way from these
    aggregated metrics  to making these  predictions  spatially at all of these small  estuaries. Dr. Gallegos
    responded that they will examine whatever data they can obtain. There is a lot of data for the Road River.
    About 30 of  these systems have Chesapeake Bay program stations, and they should be able to obtain some
    aggregate measures. There also are a growing number of these systems that have Maryland Department of
    Natural Resources  Eyes on the Bay stations that have probes  recording at 15-minute intervals. They will
    be using data from these types of stations to develop relationships between exchange and other metrics.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
     Development of a Regional-Scale Model for the Management of
                  Multiplestressors in the Lake Erie Ecosystem

                             Joseph F. Koonce and Benjamin F. Hobbs
       Case Western Reserve University, Cleveland, OH; Johns Hopkins University, Baltimore, MD

                                            Abstract

    The objective of this research is to develop a regional-scale, stressor-response model for the management
of the Lake Erie ecosystem. Stressors addressed include effects of land use changes and Total Maximum Daily
Load (TMDL) targets for nutrients, habitat alteration,  and natural flow regime modification at the scale of
individual watersheds, coupled with whole lake ecosystem effects of invasion of exotic species and fisheries
exploitation. Model predictions focus on effects of stressors on production and abundance of Lake Erie fish
populations as indicators of the health of the Lake  Erie ecosystem and  will be incorporated  into a multi-
objective decision making tool for use by Lake Erie water quality and fisheries managers along with other
resource  planners.  The research approach involves  joining multi-level modeling  with multi-objective risk
decision tools. The research plan focuses on: (1) linking changes in watershed habitat and nutrient loading
regimes proposed for the TMDL process to Lake Erie ecosystem health; (2) quantifying uncertainties in model
predictions and determining the effects of uncertainties on management decisions; (3) evaluating interaction of
stressors, particularly focusing on cross-scale additivity of stressors; (4) developing tools to evaluate  ecological
risk of land-use changes  in watersheds of the Lake Erie ecosystem; and (5) identifying and evaluating critical
break-points in ecosystem integrity of the Lake Erie ecosystem and of its integrated management. Highlights
of research of the second year of the project (June 1, 2004 to May 31, 2005) included:

A  Completion of field work and testing of models for establishing  a habitat supply inventory  for the entire
    Lake Erie watershed. Products include one MS Thesis, two manuscripts submitted for publication, and one
    manuscript  in preparation.  Work  also  has  involved  developing both  ESRI  and open   source
    implementations of Geographic Information System (GIS) data analysis layers for use with public groups
    and managers.

A  Using models (IHACRES and SWAT) parameterized in task 1.2, work has continued to use  models to
    develop a functional (hydraulic transport)  representation of land cover effects on flow and nutrient
    loading. The product of this work is currently an M.S. Thesis, which is nearing completion.

A  Assembly of a component-based DEVS modeling  and  simulation framework to  perform cross-scale
    analysis of the interaction of stressors.  The  products are a new  software package and  a number of
    presentations. Work is coordinated with the  Everglades ATLAS model. Products include a software
    library, a modeling framework that incorporates a DEVS modeling and simulation platform, and model
    repository for assembly and execution of hierarchical models.

A  Development and testing of a decision analysis framework to explore the tradeoffs associated with dam
    removal from selected tributaries in the Lake Erie ecosystem.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Joseph Koonce

A  One participant commented that the model is incredibly detailed and that it seems that the uncertainty
    analysis will be a daunting task. The participant asked if Dr. Koonce anticipated fully characterizing the
    error terms in the model parameters and the model specifications. Dr. Koonce responded that there is no
    question that there is pattern in the parameter space of these complicated models. The challenge is to have
    a framework in place so that they can easily generate the quantities of data that they need to characterize
    the patterns so they can begin to understand how the uncertainties actually work. A variety of parameter
    combinations give the same output predictions. There are other computational tools becoming available to
    do functional analysis. They are hoping to apply them  in the parameter space. There are some very nice
    algorithms  to begin to look for these patterns. In some  of the preliminary work  they  have  done in
    disaggregating fish population into age groups and into cohorts, they know that there is structure that there
    is structure in the parameter space.

A  One participant commented that they have been trying to develop good models for predicting phosphorus
    loading, and asked what tools they are using  and how well they work. Dr. Koonce responded that the
    International Joint Commission is collecting monitoring information on loadings. Unfortunately,  with the
    changes in the Great Lakes water quality agreement in 1988, some of the monitoring schemes  begin to
    break down. Dave Dolan of the University of Wisconsin at  Green Bay  is continuing to maintain the
    databases  on river flows,  sewage  treatment, and effluents so that they  are tracking the loading. The
    problem with the  loading calculation is that all phosphorus in not equal. It may  be the case that  with the
    reduction in the sewage treatment plants of  detergent phosphorus, there are  more resistant forms of
    particulate phosphorus as the primary component of the loading. There is not a lot of good information on
    the composition of the loading. There are fairly good estimates of the seasonality and loading. In the Lake
    Erie ecosystem, there are  four  dominant tributaries in the connecting  channel that makes  it easier to
    investigate.

A  Iris Goodman asked which break points in the ecosystem functions they were focusing on that might have
    the best results. Dr. Koonce responded that almost all of the break points that they know  exist  in the
    system have to do with the fish community composition. When predator-prey abundance tends to achieve
    certain threshold levels, the chance events that come with the strong year  class  of walleye, for example,
    can send the system into a very long-term predator-prey ossolation. This happened in 1988. The  fisheries
    preference is to have a lot of large body predators in the systems. The management always is tending to
    put the system at risk.
           The Office of Research and Development's National Center for Environmental Research

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       Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
      Regional-Scale Statistical Models
     for Environmental Decision-Making
The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
              Adaptive Implementation Modeling and Monitoring
                                  forTMDL Refinement

                                       Kenneth H. Reckhow
                                   Duke University, Durham, NC
                                            Abstract

    The primary objectives of this project are to: (1) develop an adaptive implementation modeling  and
monitoring strategy (AIMMS) for Total Maximum Daily Load (TMDL) improvement; and (2)  apply  and
evaluate AIMMS on the Neuse Estuary nitrogen TMDL in North Carolina. For this study, the  models in
AIMMS  are the NeuBERN Bayes network estuary  model linked with a Bayesian version of the U.S.
Geological Survey (USGS) Neuse SPARROW model; AIMMS allows us to  analytically integrate TMDL
modeling with post-implementation monitoring to refine and improve the TMDL over time.

    After the completion of the Bayesian analysis of SPARROW, we focused on two fronts. First, we started a
series of studies on the use of a simple Bayesian approach  for  updating nutrient loadings and nutrient
concentrations.  Second, we started to use the Neuse River Digital Watershed (from the  NSF-CUAHSI
program) to provide annual nutrient loading data and revise our Bayesian SPARROW model to update model
parameters as well as estimate nitrogen loadings  when new data are available.  In this report, we describe
progress made in these two areas.

    Information synthesis is usually the motivation for employing Bayesian analysis; thus, Bayesian analysis
serves  as  perhaps the ideal approach  for the  analytics  of adaptive  implementation.  The conventional
application of a Bayesian approach emphasizes the combination of prior information (in this case, from the
TMDL forecast model) and a single set of data (post-implementation monitoring data). It is shown, however,
in Bayesian statistics texts that  sequential updating using the posterior from the previous step as prior is
equivalent to updating using all of the data together; thus, sequential updating provides a means to investigate
possible temporal patterns in the data, which is attractive for adaptive implementation of a TMDL.

    As an  example of sequential Bayesian updating for adaptive implementation of a TMDL, a series of
computer programs were developed to automate the process of updating water quality concentration estimation
from model predictions and subsequent monitoring data. These programs use  Bayesian analysis  results for
(log) normal random variables,  and the conjugate family of prior distributions. The process has three steps.
First,  a number of procedures  were  developed for converting TMDL model  forecasts  of water quality
concentrations  to a prior distribution of the underlying  concentration distribution parameters.  Second,  a
program was developed to produce the  posterior  distribution of the underlying concentration distribution
parameters and the posterior predictive  distribution of future observations, based on the  pre-TMDL model
forecast (the "prior") and the first year of post-implementation monitoring data (the "sample").  Third,  the
"posterior" distribution of the underlying concentration distribution parameters is then  converted to a prior
distribution of the  same parameters for the next  time period, and the process repeats when new data are
available.

   To demonstrate this  process,  a Bayesian  SPARROW  model-predicted  1992 nitrogen concentration
distribution for the Neuse  River Estuary was used to develop a prior distribution of the mean and variance of
log nitrogen concentrations, and the sequentially updated posterior predictive distributions for each subsequent
year. The same process was repeated for the chlorophyll  a concentration distribution in the Neuse  River
Estuary. The prior distribution for chlorophyll-a was developed using an empirical model (NeuBERN) and the
results from the  SPARROW model. Although the  prior distribution based on NeuBERN overestimated the
chlorophyll a  concentration, the sequentially updated posterior  predictive distributions (based on post-
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
implementation measurements) quickly  converged to a distribution  similar to  the observed chlorophyll-a
concentration data.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Kenneth Reckhow

A  One participant commented that he thought that much of the Neuse was phosphorus limited. He asked if
    that would explain the poor prediction for chlorophyll-a. Dr. Reckhow responded that he  agreed. The
    challenge is how to conclude definitively that a water body is limited by a particular nutrient. They will
    add a phosphorus component to the model.

A  One  participant  asked  what  approach would  be  used  to  reparameterize  SPARROW to  handle
    subcatchments. Dr. Rechhow responded that they will use approaches that allow them  to  estimate
    parameter sets that will capture the covariants. They will not be identifying individual parameters.

A  One participant commented that that you are exceeding expectations when you have very low chlorophyll
    levels. From his  recent experience, there is  considerable discussion among stakeholders to establish a
    lower criterion. Dr. Reckhow responded that the results he presented  are not widely known;  people have
    not recognized how much things have improved in the Neuse. One of the recommendations in  the National
    Academy of Sciences study of the  TMDL program was for the states to take the triannual review of
    standards more seriously.

A  Iris Goodman commented that it is a challenge for everyone to develop ways to communicate to people in
    the fastest, most expeditious way to get to the answers they are seeking. Dr. Reckhow responded that you
    should try to listen to both the monitoring and modeling  people, but  ultimately the monitoring data may
    begin to dominate.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
    Bayesian Methods for Regional-Scale Stressor Response  Models

                                          Conrad Lamon
                                   Duke University, Durham, NC

                                             Abstract

    We developed regional-scale eutrophication models for lakes, ponds and reservoirs to investigate the link
between nutrients and chlorophyll-a. The Bayesian TREED (BTREED) model approach allows association of
multiple environmental stressors  with a biological response  with  simple  linear models,  while  identifying
subsets of the data in which the models fit well. Nutrient data for lakes and ponds (water body type = 4) and
reservoirs  (water body type = 5)  across the United States  were obtained from the U.S. Environmental
Protection Agency (EPA) National Nutrient Criteria Database. The nutrient data consist of measurements for
both stressor variables (such as total nitrogen and total phosphorus), and a response variable (chlorophyll-a),
used in the BTREED  model.  Variables used in subsetting include ecoregion, water body type,  month and
categorical variables representing the nitrogen and chlorophyll analytical methods used. Markov chain Monte
Carlo (MCMC) posterior exploration is used to guide a stochastic search through a rich suite of candidate tree
structures to obtain models  that better fit the data.  The Bayes factor provides a goodness of fit criterion for
comparison of resultant models. We randomly split the data into training and test sets; the training data were
used in model  estimation, and the test data were used to evaluate out of sample predictive performance of the
model. An average  relative efficiency of 1.02  between the training  and  test data for the four  best fitting
(highest log-likelihood) models suggests good performance in out of sample predictive efficiency relative to
other eutrophication models. We found that the 98,169-observation dataset produced large, complex trees,
making  their structure difficult to interpret. Adjustments may be made to priors to control the size/complexity
of resulting TREED models, improving interpretability to some extent. Some increased complexity, however,
stems from the binary tree structure itself. We therefore intend  to address these problems on two fronts. First,
we are working to incorporate  more predictor variables into our dataset for use in the end node models, in the
hope of reducing the need to explain  variability in the chlorophyll-a response with added  complexity in the
tree structure.  Second, we are  in the process of shifting our modeling framework to a more purely Bayesian
Hierarchical one, in which the  binary tree structure is absent. Knowledge of the tree structure identified using
the BTREED approach will  provide valuable information for use in determination of the hierarchical structure
for use in the new framework.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants:  Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. E. Conrad Lamon

A  One participant commented that he had chaired an NRC committee on coastal eutrophication. They were
    asked by Congress and EPA's Office of Water to comment on nutrient criteria development for coastal
    waters. The committee had a strong consensus that concentration data were not helpful and that the criteria
    should be  loadings  to estuaries.  The response of estuaries  is not well correlated with  standing
    concentrations.  Total nitrogen and total phosphorus have  a  lot nonbiologically active pulls  (e.g.,
    phosphorus is stored in all sorts of inorganic forms).  What managers are managing are the inputs, not the
    concentrations. He asked if Dr. Lamon would consider looking at load as one of the variables as opposed
    to  concentrations for their lake  analysis, and wondered what  the advantage is  to be  able to predict
    chlorophyll from either total nitrogen or total phosphorus in the data set. Dr. Lamon responded that you
    need to know the relationship between nutrients and chlorophyll  to reduce chlorophyll. At an annual
    average scale, you may get better results with load. They are using the nutrient criteria database and they
    do not have load information. They could go to the upstream river locations of each lake and find USGS
    data to map and calculate loads, which may be easier and better than using SPARROW estimates.

A  One participant commented that he just completed a project where the task was to identify the commonly
    measured criteria that are most predictive of the designated use. He consistently found that chlorophyll
    was the best predictor of designated use, which suggests that what Dr. Lamon is doing is appropriate. He
    also stated that they commented on the National Academy of Sciences study on TMDLs as to where the
    criterion should be placed. If you stop with load,  there is a good deal of hidden uncertainty between load
    and designated use that is missing from the prediction. You move  from action, load, concentration, and
    then chlorophyll or some biological response in the designated use.  If designated use is the driving factor
    in the objective, their structural equation modeling strongly suggested that chlorophyll was the appropriate
    predictor for eutrophication related impacts.

A  Iris Goodman commented that  Dr.  Lamon's analysis  showed the strong importance of method  in
    controlling the trees. She asked if Dr. Lamon would prepare a 500-word essay that could be distributed to
    EPA Program  Offices.  Dr. Lamon agreed to prepare the essay. She also  commented that in looking at
    some  CART techniques that are not Bayesian based, one of the important aspects of those methods for
    users  is to be  able  to do  interpretation on the tree structure itself. She  urged the group in their
    collaborations to begin looking at  additional kinds of predictor variables that ultimately are useful for
    managers to gain a better understanding of the issues that they  need to address. She offered to provide
    contacts from the landscape ecology grants who might have suggestions on important predictor variables
    that are ultimately useful for interpreting the tree structure.

A  One participant asked if the BTREEDs were inverted multiple regressions rather than reverse ANOVA. In
    nutrient criteria development, one of the issues is how rigid the breaks are between 2.6 m and 16.3 m
    depth. He asked if one would expect a different relationship between loading, concentration, and endpoints
    like chlorophyll-ess or biological diversity to break at those specific levels, or if it is just  a continuous
    gradient between nutrient  concentrations and chlorophyll and it happens to be breaking at those points. Dr.
    Lamon responded that the breakpoints were not absolute or precise.  This is an exploratory type method to
    indicate the important structure in the data that can be further developed with a fully Bayesian hierarchical
    approach in which a distribution on the split point could be obtained. The method does identify the change
    points fairly well. The participant asked if Dr. Lamon had classified the systems based on size but not on
    DOC. Dr. Lamon responded  that there were fewer DOC than nitrogen or chlorophyll measurements to go
    with the phosphorus. The participant commented that the first step is to classify what you predict to find in
    the system so natural features are used to classify expected conditions. The next step is to look at how the
    systems vary along a phosphorus gradient (e.g., how a valued attribute such as chlorophyll changes along a
    phosphorus gradient). Dr. Lamon responded that it is  classifying based on  the change points and then the
    continuous is in the regression model.
           The Office of Research and Development's National Center for Environmental Research

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                Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
       Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
One participant asked how the model could be used to predict the effect of environment changes, such as
climate change. Dr. Lamon responded the model could be used to the extent that climate changes cause
changes in nitrogen or phosphorus concentrations in a lake. Temperature, however, is not included in the
model. If temperature were included for climate change predictions, it would be outside of the range for
past observation, which could be a problem with regression-based methods.
       The Office of Research and Development's National Center for Environmental Research

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                   Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
     Developing a Risk Propagation Model for Estimating Ecological
      Responses of Streams to Anthropogenic Watershed Stresses
                              and Stream Modifications

              Vladimir Novotny1, Elias Manolakos1, Timothy Ehlinger2, Alena Bartosovd2,
                  Neal O'Reilly3,Ramanitharan Kandiah1, and Ferdinand Hellweger1
            1                                  2
            Northeastern University, Boston, MA; University of Wisconsin, Milwaukee, Wl;
                  3Illinois State Water Survey (University of Illinois), Champaign, IL

                                           Abstract

    The goal of this research is the development of a regionalized watershed-scale model to determine aquatic
ecosystem vulnerability to anthropogenic watershed changes, pollutant loads, and stream modifications (such
as impoundments and riverine navigation).

The tasks completed are:

A  Development of the database software shell.
A  Development of a watershed loading Geographic Information System (GIS) based model.
A  Development of Neural Net algorithms for modeling input/output (cause/effect) response of the ecological
    system (supervised ANN learning).
A  Development  of  Neural Net  unsupervised Self-Organizing Maps  (SOM),  followed by Canonical
    Correspondence Analysis derived (mined) from two large databases.
A  Analysis and  quantifying the risks expressed  as Maximum Species Richness relationships for major
    stresses.

    The workshop presentation features an application of unsupervised Artificial Neural Networks (ANN)
yielding SOM. Indices of Biotic Integrity (IBI) and its metrics for fish were analyzed by ANN, followed by
Canonical Correspondence Analysis (CCA) to extract (mine) knowledge on the impact of watershed and water
body stresses on biotic integrity of receiving waters.  Two large databases of measurements  of about 50
parameters, including fish numbers  from 2000 sites in Maryland, and about the same number of sites and a
greater number of parameters from  Ohio were  used  for the analysis, development and testing  of the
methodology. Self-Organizing Mapping by ANN discovered nonlinear  clustering of the  fish metrics of the
IBIs that was then overlaid with clustering of environmental variables to find correlation between the metrics,
their clusters  and individual impact parameters. CCA then quantitatively identified  the parameters of the
greatest importance, the Cluster Dominating Parameters. This analysis has wide spread ecological implications
and enables quantitative assessment of the impact of multiple stresses on IBIs and similar multimetric biotic
indices.

    Using the  information  on the  top Cluster Dominating Parameters, an input-output ANN model  was
developed by supervised learning using the Ohio database. The model was very accurate for  data  used in
calibration (randomly selected 75% of data, R =  0.99)  and adequately accurate for verification with the
remaining 25 percent of data (R=  0.76).

    The team members have created a Web  site where all reports and other publications or their abstracts will
be available:  http://www.coe.neu.edu/environment.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Vladimir Novotny

A  One participant asked how much the SOM was picking up the natural variabilities that the State of Ohio
    uses in their classification of expectant conditions in the weather to the streams.  Dr. Novotny responded
    that it has something to do with the ecoregions. The northwest is part of the Lake Erie ecoregion. There
    was some relationship to ecoregions. Dr. Manolakos commented that they are training the SOM based on
    the metric scores as recorded in the database. They assume that the metric scores take into account the
    location of the sites.
           The Office of Research and Development's National Center for Environmental Research

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      Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
     Regional-Scale Population Models
     for Environmental  Decision-Making
The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems


            Effects of  Multiple Stressors on Aquatic Communities
                              in the Prairie Pothole  Region

       Patrick K. Schofj, Lucinda B. Johnson , Glenn G. Guntenspergen , and W. Carter Johnson
              University of Minnesota, Duluth, MN;  U.S. Geological Survey, Patuxent, MD;
                            3South Dakota State University, Brookings, SD

                                              Abstract

    The Prairie Pothole Region (PPR), forming the northeastern edge of the Great Plains, encompasses a large
area of diverse wetlands that represent crucial  aquatic resources for flood control and aquatic and terrestrial
production. Because most of the PPR is subject to mixed use agriculture and open grazing, the wetlands are
routinely exposed to a variety of anthropogenic stressors, such as pesticides, nutrients, and domestic animal
pathogens. In addition, higher latitudes are exposed to increased  ultraviolet B radiation (UV-B).  Climate
models indicate that  the  PPR  is  likely  to be  severely impacted by climate  change through increasing
temperature and reduced precipitation.

    The overall goals of the project are to: (1) quantify  the relationships among factors directly affected by
climate change (e.g., hydroperiod), differing land use, and amphibian community structure and composition in
the prairie pothole region; (2) quantify the relationships among physical and chemical wetland attributes (e.g.,
hydroperiod, thermal regime, pH, and DOC), UV-B radiation, and land use (including associated pesticide use)
on  amphibian organismal and community responses; (3) quantify the effects of multiple stressors (shortened
hydroperiod,  increased UV-B radiation, and atrazine exposure)  on the health and organismal responses of R.
pipiens; and  (4) use regional climate scenarios  and hydrologic models in conjunction with empirical data
gathered through field and mesocosm studies to predict potential effects of multiple stressors on prairie pothole
wetlands and their associated amphibian communities.

    Data on stressor impacts were analyzed at three spatial scales:  landscape (67 sites), wetland (35 sites), and
mesocosm. Sites within the  landscape and wetland scale studies  were designated as seasonal (SS) or semi-
permanent (SP) and were classified further as crop or grassland  land use. Landscape-scale (level I) study sites
are distributed across the U.S. portion of the PPR; wetland-scale (level II) study sites are concentrated in east-
central South Dakota. Mesocosm studies (level III) were conducted at the Oak Lake  Field Station of South
Dakota State University.

    Eleven amphibian  species were observed in total, and species richness  per wetland ranged from zero to
five. No species richness differences were observed  between row crop and grassland wetlands, however, more
species were observed in Central Tall and Northern Tall Grassland Ecoregion wetlands than in Prairie Coteau,
Northern Short and Northern Mixed Grassland Ecoregion wetlands. Northern Leopard Frog (Rana pipiens)
was represented across the entire PPR, with adults in 44 sites breeding evidence in 29 sites. Logistic regression
indicated probability of R. pipiens presence was  significantly influenced by the interaction of hydrology  and
land cover (p = 0.02), while R. pipiens breeding  in  a wetland was significantly influenced  by hydrology, but
not by landcover or  an interaction of the two treatments (p = 0.08).

    Fewer of the wetland scale sites produced numbers of metamorphic R. pipiens necessary for malformation
surveys in 2004 than in 2003. Seven of 13 sites (54%) surveyed produced malformed frogs.  In these sites, a
total of 3.5% (26/748) displayed at least one identifiable malformation. As in 2003, hindlimb malformations
constituted a majority  (71.4%) of the total. Malformation prevalence  was  not significantly correlated with
surrounding land use or atrazine concentration.  Metamorphic frogs were collected from wetlands representing
a range of land-use types for  analysis of gonadal dysmorphogenesis.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants:  Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
    Based on a repeated measures ANOVA including both intensive and extensive sites, hydrology and land
cover were significant predictors of several  water quality parameters. Seasonal wetlands were significantly
more alkaline than semi-permanent wetlands, with seasonal crop wetlands significantly more alkaline than all
other treatments (p < 0.001). Land cover also influenced specific conductivity (uS) and DOC (ppm), both of
which were significantly higher in wetlands surrounded by grassland than row crop (specific conductivity, p =
0.056 and DOC, p < 0.0001; intensive  sites only). As expected, hydrologic regime influenced maximum depth
and  water temperature (both day  and nighttime); semi-permanent wetlands  were deeper  and colder than
seasonal wetlands.

    UV-B radiation surface levels and attenuation rates (through the water column) were measured in 20 sites
in 2003 and in 34 sites in 2004. UV-B was rapidly attenuated through the water column [Kd (attenuation rate) =
6.24 - 58.93 m"1]. Preliminary analysis indicates that DOC and color, which are the dominant factors in UV-B
attenuation in lakes, may not be the primary influences on UV-B attenuation in PPR wetlands.

    Triazine (atrazine and simizine) concentrations assessed in  water collected in mid-April, mid-May,  and
late June 2004,  ranged from non-detectable (< 0.01 ppb) to 7.124 ppb, with concentrations jj, 0.01 ppb present
in 71 percent of wetlands sampled in Survey 1, and in 100 percent of wetlands in Surveys 2 and 3. Triazine
concentrations were higher in wetlands where  land use within a 90 m buffer was classified as > 70 percent
crop than in those where grassland  comprised  the greatest proportion of the buffer ([ 7.124 ppb vs. [ 0.657
ppb, respectively).  Semi-permanent wetlands  with  corn in the 90 m  buffer  had higher mean  atrazine
concentrations,  and corn presence was  the best  overall predictor of wetland atrazine concentration for Surveys
2 and 3 (ANOVA, p = < 0.001-0.025).  However, neither land use (crop vs. grassland; ANOVA, p = 0.662) nor
hydrologic regime (ANOVA, p = 0.878) were significant predictors of maximum atrazine concentration in
April-July 2004.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Patrick Schoff

A  One participant asked how far away the grasslands wetlands are from where the atrazine is used, and what
    the distance is over which the drift would be occurring. Dr. Schoff responded that it is a large drift and it is
    reasonable. It always is windy in the Prairie Pothole Region. One of the challenges in the 2003 season was
    to conduct UV attenuation measurements because  the water surface  has  to be calm. It would be calm
    before 10  a.m. and after 5 p.m. The original presumption of the study was that atrazine would be run-off
    from agricultural fields. In this area, it does not appear to be happening.

A  One participant asked why the DOC was not related to UV attenuation, and whether it is because the UV
    attenuation varied but not the DOC concentration. Dr. Schoff replied that the statement was correct. The
    participant commented  that  in  areas  with a lot of sun and  long residence  time, there could much
    photobleaching, which could change the transparency. Dr. Schoff responded that there is  a lot  of wind-
    driven mixing that takes place.

A  One participant asked how the atrazine is applied. Dr. Schoff replied that much of the atrazine was applied
    by air. The participant asked if the sites were small or big fields  and whether the grassland and crop land
    potholes were next to each other. Dr. Schoff responded that they attempted to locate crop sites that were
    embedded within a cornfield and were able to find about 50 percent of the sites within the vicinity of a
    cornfield. In North Dakota and South Dakota, most of the corn is grown for forage; therefore, the fields are
    smaller and more interspersed. In Iowa and Minnesota, they had a harder time finding crop sites.

A  One participant asked if atrazine could be moving through the groundwater. Dr. Schoff responded that it
    could. The participant asked if GIS and distances from crop fields could be used to look at  potential
    controlling factors. Dr. Schoff responded that a long-term study of the hydrology of the potholes  has been
    set up in the Prairie Coteau  ecoregion. He commented that their study is being done under a period of
    drought. Some areas are persistently wet and some are persistently dry. He suggested that EPA may wish
    to consider establishing a long-term study program to long at a 10-year time scale and capture some of the
    natural variations.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
        Developing Relations Among  Human Activities, Stressors,
       and Stream Ecosystem Responses and  Linkage  in Integrated
                           Regional,  Multi-Stressor Models

             R. J. Stevenson1, M. J. Wiley2, D. Hyndman1, P. Seelbach2, and B. Pijanowski3
         Michigan State University, East Lansing, MI; 2 University of Michigan, Ann Arbor, MI;
                               3Purdue University, West Lafayette, IN

                                            Abstract

    Nutrients, dissolved oxygen (DO), and hydrologic alteration of streams are commonly affected by humans,
and all have profound effects on valued ecological attributes (VEAs). Few models explain relations among
human activities, these stressors, and VEAs with sufficient precision for nutrient criteria, Total Maximum
Daily Loads (TMDLs), and stream management. The  objectives of our research are to refine relationships
among human activities, multiple common  stressors,  and the  fisheries and  ecological integrity  of stream
ecosystems.

    A multi-scale strategy is being employed to refine  several tools used in water quality assessment. At the
broad spatial scale, stream conditions throughout the southern Michigan region were surveyed  and  existing
data from a variety of sources were compiled. We refined stream survey methods to relate early morning DO
to human activities, contaminants and habitat alterations, and VEAs by sampling conditions at low flow, more
than 3  days after rain events, and during early morning hours; thus controlling variation in DO as a result of
natural factors. Preliminary results show: nitrogen and phosphorus concentrations were positively related to
agricultural land use in watersheds; algal biomass increased with nutrient concentrations; and early morning
DO concentrations decreased with increasing algal biomass. Interestingly, indirect relationships in the causal
pathway from land use to nutrients,  algal  biomass,  and  low DO often were more precise than direct
relationships, which indicates high temporal variation in intermediate factors.

    At finer scales, we established master watersheds with either continuous DO and water quality monitoring
or spatially intensive  and repeated sampling.  These  watersheds will be used to parameterize processed based
models. The instrumentation and continuous monitoring  of Crane  Creek is  providing parameters  for DO
responses to complex interactions among processes operating at three temporal scales: (1) diurnal variation
with light periods and photosynthesis;  (2) daily development between weather-related  events of biological
assemblages that regulate diurnal variation in DO; and (3) weekly variation in weather disrupting hydrology of
streams and related biological community development.

    A processed-based  model relating precipitation and land use to water quantity and quality  was refined
using intensive sampling of Cedar Creek. The model shows the importance of groundwater routes of transport
of contaminants to streams in the poorly developed soils with high permeability. These soils are  typical of
many watersheds in the glaciated region of the upper Midwest and Great Lakes Region. Nitrate concentrations
in Cedar Creek were predicted  much better by a model  that included groundwater inputs than traditional
models without it. A 10-year simulation of the Cedar Creek watershed highlighted the significant role land use
plays in influencing the distribution of nutrient concentrations in groundwater and in streams.

    Future activities will integrate results of our broad and fine scale field  assessments in a suite of statistical,
processed-based,  and hybrid models.  Many of our  statistical models  are  being  used  by the  Michigan
Department of Environmental Quality to establish nutrient criteria. We will continue to refine our models to
improve understanding of how human activities can be managed to  support ecological integrity, aquatic life
use, and fisheries of stream ecosystems.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
                  Application of Individual-Based Fish Models
                             to Regional Decision-Making

                              Roland Lamberson and Steven Railsback
                              Humboldt State University, Humboldt, CA

                                             Abstract

    This project's goal is to develop and  demonstrate the usefulness of individual-based models  (IBMs) of
stream salmonids as a tool for regional decision-making. The specific objectives are to:  (1) adapt our IBM that
simulates stream reaches to watershed-level assessment; (2) conduct a demonstration assessment; and (3)
examine uncertainties and sensitivities in the regional assessment.

    We are using and enhancing inSTREAM (individual-based stream trout research and assessment model),
an existing IBM  that represents how flow  regimes and water quality parameters  such  as turbidity and
temperature affect individual trout and, consequently, trout populations. The first objective is being met by
developing  ways to synthesize input for inSTREAM from data that  are commonly available for western
streams. The second objective is being met by conducting an example assessment of how changes in turbidity
regime and flow regime, and presence of an exotic predator fish, affect a watershed's trout populations. The
third objective is being met by two studies; one examines parameter uncertainty and sensitivity in inSTREAM
applied to a  single reach,  and the  second examines how sensitive model  results  are to uncertainty and
variability in the channel shape and hydraulic input used to represent a site.

    The preliminary results  are:  (1) Stream habitat survey data collected by the California Department of Fish
and Game has been combined with other widely available information and stochastic modeling techniques to
synthesize input for inSTREAM. These methods can be used to generate input representing  a variety of sites
within a region. (2) Site-specific example assessments  show that  inSTREAM is useful for predicting trout
population responses to stressors such  as flow regime  alteration,  increased turbidity, and introduced fish.
Collaborative research with U.S. Forest Service scientists is  improving our model of a key process:  how
turbidity affects fish feeding efficiency. We also used  inSTREAM to model interactions between wild trout and
stocked hatchery trout, and how the interactions could change if hatchery practices are changed to enhance
survival of stocked fish. (3) A parameter uncertainty  analysis  showed that the primary output of inSTREAM,
adult trout biomass, is not  highly  sensitive to any unexpected parameters and that the model can easily be
calibrated to reproduce the observed size and abundance of yearling and adult trout.

    Our results so far confirm that inSTREAM can be, when applied  and analyzed carefully, a uniquely
powerful tool for understanding the effects of multiple stressors on fish populations. The model is now in use
by several resource agency and university scientists, and we conducted our first training class in July 2005.

    In the final year of the project, we plan to finalize a public release of inSTREAM, including its software, a
complete description  of the model, and a  guide to using it. These products are now in peer review prior to
publication. A demonstration assessment will be completed using the South Fork Eel River watershed as a site.
The analyses  of uncertainties and  sensitivities will be completed with studies of how sensitive the model's
ranking of management alternatives is to uncertainty in parameters and in site-specific input data.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Roland Lamberson

A  One participant asked if the turbidity took into account watershed properties or just flows. For example,
    watershed properties  such as  logging could have  a big  impact on that relationship.  Dr.  Lamberson
    responded that turbidity was just an input parameter. They have a model for turbidity that they use in some
    cases to generate data.

A  Iris Goodman commented that this was an interesting effort with a lot of challenges to try to scale it up to a
    regional application. It also could be very useful as a heuristic device in a simulated  situation where you
    could  take a  simulated  hypothetical  system to try to  reproduce  and understand  the  most  critical
    combinations of stressors. Dr. Lamerson responded that one of the major thrusts of the model is to be able
    to use it to look at individual behavior characteristics and how they impact the emergent population levels.
    They have looked at habitat selection and the interactions between wild and hatchery fish. In developing
    the model, they looked at density dependence in fish populations.

A  One participant asked how the sensitivity impacts were calculated. Dr. Lamberson responded that they
    used professional judgment to establish  the reasonable range for the  parameter value. They then did
    simulations to investigate sensitivity of abundance of adult mature fish.

A  One participant asked how important parameters for the indices of fish integrity (e.g., embeddedness,
    substrate, gradient) were incorporated  into their model. Dr. Lamberson responded that they have detailed
    habitat structures. The stream structure is the actual stream structure from a real stream in California.
    There is  difficulty in reproducing characteristics of a river because of problems  in reproducing the
    gradients. Their gradients  are much deeper; they used digital  elevation maps to reproduce the gradients.
    Dr. Steve Railsback commented that  they did  not  directly  input emeddedness. They look at habitat
    parameters that reflect the amount of velocity shelter. If a substrate is coarse and large, there are places
    where fish can sit behind it and reduce its swimming speed, which reduces how much energy it needs to
    grow.  If it is a highly embedded  substrate, there are no velocity shelters. If the fish wants to sit in the
    current and feed, then it has to swim against the whole velocity of the river. Embeddedness also may affect
    food production. They do not try to model growth and production of the food that the fish eat because it
    could double or triple  the complexity of the model. They do try to calibrate the model to try to reproduce
    observed growth rates by the adjusting their food production  parameter. Substrate embeddedness would
    affect the food production. Channel shape and gradient are in the model but indirectly because they are in
    the hydrolic model that predicts the depth and velocity of the cells at different points for a different flow.
           The Office of Research and Development's National Center for Environmental Research

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                   Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
     Multiple Threats to Marine Biodiversity:  The Interactive Effects
        of Climate Change and Land Use Patterns on the Alteration
               of Coastal Marine Systems by Invasive Species

                                      RobertB. Whitlatch
                               University of Connecticut, Groton, CT

                                           Abstract

    Ecological responses of global warming are expected and coastal ecosystems are particularly vulnerable
because they are less buffered from temperature increase than more oceanic systems. Resulting alterations in
species distribution patterns, coupled with the enhanced vulnerability to invasions by exotic species, can result
in profound changes in communities and ecosystems. Added to the effects of climate  change is the intense
human-related use of these areas, which  have resulted in a host of problems that  often lead  to habitat
degradation and reduced ecosystem function and biodiversity.  We have been using the southern New England
coastal zone as a model to study the interactive effects of climate change, land use and invaders on ecosystem
function and biodiversity. The abundance of invaders has increased during the past 20 years and there has been
a decline in the numbers of resident species. Recent invaders  are almost exclusively found in coastal systems
that possess reduced biodiveristy and that are most heavily impacted by human activities. In addition, there are
strong within-habitat inverse relationships  between resident diversity and invader diversity, suggesting that
variations in local environmental conditions that influence local biodiversity are important components in
response of coastal ecosystems to invasion susceptibility.
          The Office of Research and Development's National Center for Environmental Research

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                     Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Whitlatch

A  Iris Goodman asked Dr. Whitlatch to discuss the  implications on a functional  basis of the increased
    cuttlefish invaders. Dr. Whitlatch replied that this most recent invader is causing  a lot of concern in the
    shellfish industry. It has been reported that 40 square miles of Georgia's banks are covered by this species,
    which  influences the scallop  fishery.  The  fishing  activities of the fishers  are  acting to disperse the
    organisms over a wider area. It has serious potential economic implications.

A  One participant asked if it was  a gross generalization to say that we might have some positive effect on the
    invasive species if we improve water quality. Dr. Whitlatch responded that water quality is correlated with
    it.  The chlorophyll  data  for Long Island Sound is  not very good.  These organisms  are all suspension
    feeders. It  could  be the interaction of temperature and productivity that is  actually facilitating  more
    recruitment (i.e., more eggs and sperm). As you increase the water quality of very polluted areas, you start
    to  see invaders coming in.  This also is true for shipworms. Docks that were built around the turn of the
    century were not affected by  shipworms, but  when the water quality is increased there is  a shipworm
    problem; as a result, the docks  are falling down. There  are positives and negatives for cleanup of the
    coastal zones.

A  One participant asked  if there might be threshold effects in terms of the relationship between loss of
    biodiversity and invasives. Dr.  Whitlatch responded that they have seen other types of threshold effects in
    their system. Predators of recently settled invaders are vital in controlling invaders. When those predators
    are removed or not present there is an abundance of invaders.

A  One participant  commented that Dr.  Whitlatch had shown a strong  negative relationship between
    biodiversity and invaders, and asked if it was  expected to see that relationship in other systems if space
    was not such a strong major limiting resource. Dr. Whitlatch responded that if you do the same experiment
    and use a native species  as the invader, you see exactly the  same effect. It is not  the fact that the native
    species are somehow collectively acting together to reduce the effects of a  new species invading the
    environment. They are collectively reducing the amount of available  space at  any one particular time. The
    more  species you have, the less space  you have because  of variations and fluctuations of their life
    histories. In soft  sediment systems, they have tried to do  similar experiments but there is no effect.
    Animals  are not as space limited in soft sediment systems; they live in a  three-dimensional sediment
    column, and they can partition their space both horizontally and vertically.
           The Office of Research and Development's National Center for Environmental Research

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       Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
    Climate, Land Use and UV Radiation
             on Aquatic Ecosystems
The Office of Research and Development's National Center for Environmental Research

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                   Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
     Interactive Effects of Climate Change, Wetlands, and Dissolved
             Organic Matter on UV Damage to Aquatic Foodwebs
               in the Ontonagon  Watershed, Northern Michigan

      Scott D. Bridgham1, Gary. A. Lamberti2, Carol A. Johnston3, Paul C. Frost2, James H. Larson2,
   Patricia A. Maurice2, David A. Lodge2, Kathryn C. Young2, Boris A. Shmagin3, andKangsheng Wu3
             University of Oregon, Eugene, OR; University of Notre Dame, Notre Dame, IN;
                            South Dakota State University, Brookings, SD

                                            Abstract

   Understanding the factors controlling ultraviolet radiation (UVR) flux into aquatic ecosystems is critical
given its direct and indirect effects on many ecological processes. The strongest attenuator of light and UVR in
aquatic ecosystems is dissolved organic  matter (DOM), which previous studies suggest is controlled at the
landscape scale primarily by wetland area and the discharge regimes of rivers and streams. Climate change
may  reduce DOM concentrations in aquatic  ecosystems, thereby exacerbating UVR effects, by changing the
amount and flow paths of DOM from upland and wetland ecosystems. We hypothesize that the linkages
among wetland area and type, DOM, and climate will be the most important factors determining the amount of
UVR damage to  aquatic ecosystems  at the  landscape scale.  Our  objectives are to: (1)  relate  DOM
concentration  and  chemistry in various  tributaries of a relatively pristine watershed in the Lake  Superior
drainage basin (Ontonagon River in northern Michigan) to wetland and upland landscape characteristics and
discharge via multivariate analysis; (2) determine interactions among  UVR intensity and DOM chemistry,
photodegradation, and biodegradation; and (3) determine the response of stream foodwebs to the interactions
between UVR intensity and DOM concentration and type.

   We have  addressed these objectives through a combination of landscape and hydrological analyses;
extensive sampling of water chemistry and UVR attenuation profiles in numerous streams for 2 years; analysis
of the chemistry, photodegradation, and biodegradation of DOM; and experiments quantifying the effects of
DOM concentration and source on UV damage on stream biota in a series of artificial stream experiments.

   We sampled a dozen times over a 2-year period water chemistry  and determined discharge in 35  sub-
watersheds in  the Ontonagon watershed. Additionally, we did an initial survey of 60 sampling locations within
the Ontonagon River watershed in September 2003. Thus, we have developed an extensive spatial and
temporal dataset of water chemistry within this 3600 km2 watershed. The best published landscape correlate
with  DOM flux in streams and rivers is  with soil carbon:nitrogen (C:N) ratios. As this information was not
available otherwise, we sampled 155 representative  soils in the dominant soil types within the watershed to
estimate the spatial coverage of soil C:N ratios within the watershed.

   We have  measured  the spatial and temporal variation in the attenuation of UVR in a variety of streams
within the Ontonagon Watershed and related  UVR dosage to stream biota to water depth, water chemistry, and
canopy cover. Additionally, we used plastic  dosimetry strips to obtain a better spatial and temporal of UVR
dosage within the watershed.

   Our hydrological modeling  research has  taken a two-pronged approach. First,  we have used USGS
gauging station data, land-use  data, and  factorial analysis to examine landscape controls over seasonal and
annual river discharge at four spatial levels (U.S. conterminous, U.S. Great Lakes basin, Upper Michigan, and
Ontonagon watershed). Second, we recently hired a postdoctoral associate to use a basin-scale model to predict
discharge and seasonal  DOM concentrations in all 35 subwatersheds of the Ontonagon that we have been
studying.  Substantial progress has been made on parameterizing this model, and when complete we will use
global climate model predictions to examine how climate change will  affect DOM concentration and  UVR
penetration within the Ontonagon watershed.
           The Office of Research and Development's National Center for Environmental Research

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                     Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
    We constructed a large artificial stream facility to examine experimentally how DOM and UVR interact in
controlling food-web structure in streams. A number of different experiments have been completed and are
being prepared for submission for publication.

    Our major findings to date are:  (1) As predicted, DOM is the major control over UVR dosage to aquatic
biota and in streams  and rivers with high DOM concentrations, such as the Ontonagon Watershed, most biota
experience very low UVR exposure.  (2) Although wetlands are  a significant landscape predictor of DOM
concentration and chemistry in streams, the area of different types of wetlands is important (some even having
a negative  correlation with DOM concentration),  and other factors  are important in predicting  DOM
concentrations  in the complex glacial  geology of our study area. (3)  Climate and landscape effects on
discharge and DOM concentration likely will have a much larger effect on aquatic biota in wetland-dominated
watersheds than will UVR effects.

    As soon as  the soil C and N samples have been analyzed, we will use multivariate statistics to relate DOM
concentration and chemical characteristics to season, discharge,  and landscape characteristics in one of the
most complete  datasets to have attempted this at a relatively large watershed scale. When the basin-scale
hydrological model  is fully parameterized,  we will add in our empirical landscape predictors  of DOM
dynamics to test how anticipated climate change will affect discharge, DOM concentration and chemistry, and
UVR dosage of biota throughout the Ontonagon Watershed.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Scott Bridgham

A  One participant commented that the soil C:N as a control for DOM is going to be a reflection of the
    dominant trees and it will probably be responsive to the atmospheric deposition. Dr. Bridgham responded
    that one paper that was published had a r2 = .99 (no variation) for the United States. The best correlation is
    not just the C:N ratio. In terms of cerol carbons, its value would be as an index of huminification. The
    more nitrogen, the lower the ratio;  this results in more humified  organic matter, which probably would
    reflect the amount of DOM.

A  One participant asked if the photodegradation of the DOM could be related to the C:N ratio from whatever
    forms of nitrogen are present and,  therefore, affecting different levels of production molecules such as
    hydrogen peroxide.  Dr. Bridgham responded that  this  comment was correct.  The huminification would
    have everything to do with the chromofores and their effect on light. It was beyond the scope of the study
    to look at some of the other photochemistry aspects. Most of their DOM was terrestrially derived.

A  One participant commented that in many streams the  residence time is too short to have an extensive
    photochemical effect, but it is  more likely in ponds  or lakes where it  would be a bigger factor. Dr.
    Bridgham responded that many of the streams in their  study are quite flat, wetland dominated, and with
    low flow. The other factor is high attenuation, so most  of the water is not exposed to the sun. They did a
    fair amount of photodegradation and biodegradation  work to try to understand the controls. There was a
    huge effect on DOM chemistry but not much effect on concentration.

A  One participant asked Dr. Bridgham to comment  on the role of  DOM concentration versus the optical
    properties of DOM for different wetland types. Dr.  Bridgham responded  that very little work has  been
    done in this  area.  Some studies have  looked at  different DOM concentrations, with very high DOC
    concentrations of 50 to  100 milligrams carbon per liter. There has been very little work done on mineral
    soil wetlands, including how the flow  pathways would change and the  effect of the  DOM as it  goes
    through the mineral soil down to the streams. These transport, biodegradation, and sorption mechanisms
    that will have huge effects on both the concentrations and the chemistry. Almost no work has been done in
    this area.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
   The Influence of Climate-Induced Alterations in  Dissolved Organic
Matter on Metal Toxicity and UV Radiation in Rocky Mountain Streams

              William Clements1, Jill S. Baron1, Diane M. McKnight2, and Joseph S. Meyer3
            Colorado State University, Fort Collins, CO;  University of Colorado, Boulder, CO;
                               3 University of Wyoming, Laramie, WY

                                            Abstract

    The primary goal of our research was to investigate the influence of climate-induced changes in hydrology
and dissolved organic material (DOM) on responses of stream ecosystems to the combined stress of ultraviolet
radiation (UVR) and heavy metals. We hypothesized that changes in climate and UVR will alter the quality
and quantity  of DOM in Rocky Mountain streams. Because DOM regulates light attenuation and metal
bioavailability in these systems, we predicted that exposure to UVR and metals will increase as a result of
changes in DOM. We integrated climate and hydrologic modeling  with an intensive field monitoring and
experimental  program to test the hypothesis that reductions in DOM increase bioavailability of metals and
exposure to UV-B (280-320 nm) radiation. We estimated effects of climate-induced  alterations in stream
hydrology on DOM using DayCent-Chem,  a model that simulates carbon, water, and nutrient flux to streams.
In controlled laboratory experiments with a full-spectrum solar simulator, we irradiated  DOM collected from
six field sites for 24 hours and quantified changes in Cu complexation using a  Cu2+ selective electrode.
Additionally,  we conducted field and microcosm experiments to test the hypothesis  that UV-B exposure
impacted benthic communities and that effects varied among locations along a metals gradient.

    Analyses  using the DayCent-Chem model showed that increasing temperature linearly by 2.5 C over a 50
year period increased DOC concentrations relative to control runs. Results of our monitoring studies indicated
that across 21 watersheds there  was a significant  relationship between DOM concentration  and stream
discharge. However, the timing of peak discharge and  maximum concentrations of heavy metals, DOC and
other physicochemical variables that influence metal toxicity varied among streams. Uptake of metals by the
caddisfly (Trichoptera) Arctopsyche grandis was predicted by the biotic ligand model (BLM), a model that
accounts for  physicochemical factors influencing metal bioavailability. Results  showed close  agreement
between observed and predicted metal levels in these organisms. After 24-hour exposure to simulated sunlight,
DOM absorbance  decreased  by  approximately  17-25 percent, significantly increasing  exposure of benthic
communities to UV-B. Photobleaching of DOM also increased the fraction of bioavailable Cu2+, potentially
increasing toxicity to aquatic organisms. Microcosm and field experiments conducted in Colorado and New
Zealand  showed significant  effects  of UV-B  on benthic communities.  Results  indicated  that mayflies
(Ephemeroptera) were especially sensitive  to UV-B,  and that effects differed among locations. Our findings
are significant because they demonstrate that benthic communities in shallow,  alpine streams are exposed to
intense UV-B radiation  and that  climate-induced  reductions in DOC  are likely to  increase  both metal
bioavailability and UV-B exposure. In most cases, effects of these two stressors were additive; however, there
were some examples where combined exposure to metals and UV-B were greater than either stressor alone. In
the final phase of our research we are continuing to investigate  the influence of  hydrology and increased
temperature on DOC concentration and export using the DayCent-Chem model.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. William Clements

A  One participant asked if there were data on the contribution of autochthonous versus allochthonous DOC
    to the streams. Dr. Clements responded that Dr. Diane McKnight has done work using fluorescence index
    on characterizing not just autochthonous versus allochthonous but also a detailed quantitative analysis of
    the different types of carbohydrates and carbons. There is a seasonal variation in the relative importance of
    autochthonous versus allochthonous. Allochthonous appears to dominant in these alpine streams.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
         Interactions Among Climate, Humans, and Playa Wetlands
                             on the Southern  Great Plains

              Scott McMurry, Lor en Smith, David Willis, W. P. Dayawansa, Clyde Martin,
                                 Ken Dixon, and Chris Theodorakis
                                Texas Tech University, Lubboch, Texas

                                             Abstract

    We measured avion, amphibian, and plant communities in 80 playas split between 2 years. In each year, 20
playas each were sampled in cropland watersheds and native grassland watersheds. Physical features of all
playas were measured, including sediment depth, hydroperiod, basin volume, and playa area. This project was
designed to address the hypothesis that  climatic variability and landuse practices (e.g.,  crop  production,
conversion to grasslands) dictate hydroperiod and  spatial distribution of wet playas, influencing the ecological
structure of vegetation and animal communities that rely on playa wetlands for many life requisites. All field
data have been collected, and we are in the process of analyzing all results and coordinating field data with
model projections for climate effects on playa hydrology.

    Grassland and cropland playas used in this study were in either fine or medium textured soils. Playas in
fine textured soils were typically larger and  contained less sediment than those in  medium textured soil.
Cropland playas contained more sediment (2-4 times greater) and had greater volume loss than grassland
playas, regardless of soil texture. Hydroperiod was similar between cropland and grassland playas in 2003 (100
vs.  97 days, respectively) but not in 2004 when average hydroperiod length in grassland playas was 76 days
longer than in cropland playas. Hydroperiod  differences between years likely reflect differences in annual
precipitation. Total rainfall in 2004 was about three-fold greater than in 2003.

    Analysis  of the avian and amphibian community data still is in progress. Preliminary results suggest that
overall richness of avian communities is similar between  cropland and grassland playas, ranging from six to
eight species  in each playa type. Exotic avian species were, however, typically  observed in cropland playas to
a greater degree than grassland  playas. Species richness was typically two- to three-fold greater in wet playas
than dry playas in both years. Also, avian community richness often was positively related to playa size, but
this was dependent on the hydrologic state of the playa and season (e.g., wet playas in autumn, r2 = 0.497; dry
playas in summer, r2 = 0.443).

    Average  amphibian community richness also was  similar between cropland and  grassland playas, with
about three to four species observed on average in each playa type in  2003 and 2004. Cropland playas,
however, were more likely to have no species (2003) or only one species (2004) compared to grassland playas,
which always had at least two species. Overall, species richness was strongly related to hydroperiod in playas,
with richness dropping sharply when hydroperiod fell below 100 days.

    Current modeled predictions of hydroperiod and water volume in cropland playas show marked reductions
over a 50-year time horizon, depending on the use of soil management practices such as furrow dikes or buffer
strips. Indeed, although hydroperiod may remain stable during the  first  16 years of  cultivation (no furrow
dikes), the rate of reduction in hydroperiod is rapid once it begins. For example, assuming a maximum of 123
wet days from May 1 to August 31, a typical cropland playa will have  only 100 wet  days  after 26 years,
leveling off at about 35  wet days after 39 years. In comparison, a typical native grassland playa is projected to
lose only about 5 wet  days  after  50  years under the  same conditions. These projections  are dependent on
cultivation strategies, crop type, soil texture, and  climate, but suggest the potential for rapid deterioration of
cropland playas subject to cultivation pressure, and are supported by empirical data from our study and others.
We are in the process of modeling playa hydrology  given stochastic  temperature  and  rainfall data,  and
           The Office of Research and Development's National Center for Environmental Research

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                     Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
assessing the influence of different crop types, watershed slopes, soil textures, and mitigation strategies, such
as furrow dikes and buffer strips, on hydroperiod and water volume.

    Although preliminary, our data support the rapid reduction in playa hydroperiod (and increased rates of
water loss)  as cropland playas fill  with sediment. These changes in hydrology will have effects on playa
function as related to biotic community composition. Indeed, the effect of cultivation and subsequent sediment
loading on the hydrology of cropland playas is already occurring as evidenced by  data from our study and
others. Plant, avian, and amphibian community composition are subject to these alterations in cropland playas.
For example, our data suggest that as  hydroperiod length falls below 100 days, amphibian richness suffers
from the loss of species with longer larval periods (often the rarer species in the community).
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Scott McMurry

A  One participant asked what the restoration potential was for the playa sediments. Dr. McMurry responded
    that it could be done;  however, there are questions about what the playa will look like and how it will
    function. No one knows, but it will be better than it is when it is fossilized. The participant asked if the
    vegetation regrows quickly. Dr. McMurry responded that no one knows.  The first thing that needs to be
    done is to put in protection for the playas that are left. The only reason that there are playas left in native
    grasslands is because they exist in areas that a hard to farm. There are no incentives to protect them. It may
    become economically  feasible to  protect them in the future because it  costs a tremendous amount of
    money to irrigate cotton fields by pumping out of the aquifer. It is somewhere between $3 to every $1 for
    pumping out of the ground versus pumping out of a playa. A lot of farmers pump  out of the playa. The
    problem is that no one knows if the playa will be full of water in any given year. When the playa fills up
    with sediment, then it will have water fewer times and for shorter periods of time.

A  One participant commented that he had heard that cotton was the most heavily pesticide applied crop that
    can be grown.  Dr. McMurry responded that cotton gets pesticides, herbicides, insecticides, and defoliants.
    The participant commented that the amphibians  living in these  playas are fairly terrestrial, so they are
    being  exposed both in the fields and in the playas. He asked if there was any indication of that  type of
    stressor on richness or diversity.  Dr. McMurry  responded that over the past 2 years they have been
    conducting a side  project to collect sediment in water. Last summer,  they monitored  12 playas and
    collected water samples and tadpoles each week for a month. They are in the process of analyzing the data.
    Other studies that have been conducted have shown that amphibians from cropland playas weigh less and
    have smaller body  size, and the populations tend to be denser. There are  alterations in physiological and
    immune  function endpoints.  There are effects  happening that  may have something  to do with the
    differences in the availability of food, differences in the per capita food amount, or other stressors related
    to hydroperiod. As  part of another study, they have differences between crop and grass playas with respect
    to the  rate that  the water is lost. The rate of water loss out of crop playas is  significantly faster than in grass
    playas.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
       Assessing the Consequences of Global Change for Aquatic
             Ecosystems:  Climate, Land Use, and  UV Radiation

           Bruce R. Hargreaves, Donald P. Morris, Frank J. Pazzaglia, Craig E. Williamson,
                             Richard N. Weisman, and Stephen C. Peters
                                 Lehigh University, Bethlehem, PA

                                            Abstract

    Our primary objective in this study is to determine how current stream and landscape properties in the
Lehigh River watershed influence the aquatic ecosystem response to variations in climate and solar ultraviolet
radiation  (UVR) and how  past  changes  in land use have influenced stream processes.  Our findings will
contribute to  understanding future  responses of aquatic ecosystems  to  environmental changes,  including
anticipated increases in extreme weather conditions and increases in UV-B associated with ozone destruction
in the stratosphere.

    Our approach is to examine watershed and stream properties and processes on different  scales of space and
time to learn about functional relationships that influence UV impact. Biotic responses to UVR were tested by
placing stream macroinvertebrates in a laboratory solar simulator, and by manipulating UV-B in situ for stream
trophic groups.  For stream-water shed interactions, we sampled stream water periodically across  the entire
watershed during base flow and storm flow conditions  and also established stations at  several headwater
streams with automated equipment for sampling and monitoring rainfall, canopy throughfall, and stream water.
Our samples were analyzed for properties  that influence UV attenuation. We  also made in  situ and laboratory
measurements of photobleaching rates and biolability of stream colored dissolved organic matter  (CDOM).
The role of the stream canopy  on UVR exposure was examined with two complementary  approaches: direct
measurement  of the canopy UVR transparency for specific stream reaches, and proxy  measurements for
predicting UV transparency (fisheye camera images from below the canopy and satellite images from above).
We also digitized aerial photographs that record changes in land use and stream channel morphology since the
1940s to relate current storm flow patterns  measured with in situ flow recorders.

    In  stream experiments with macroinvertebrates, the abundance of  chironomids was enhanced during
exposure  to UVR, in  spite of their sensitivity to UV-B. The optical quality  and source of DOC differed by
region:   streams in  Lehigh Valley region  were enriched in algal  CDOM whereas Pocono  streams were
dominated by wetland soil  CDOM.  On average, 14 percent  of stream dissolved organic carbon (DOC) was
consumed by bacteria during 2-day microcosm experiments, but this number increased to more than 40 percent
when the water  was photobleached by the equivalent of 2 days of sunlight. Forests have  lower DOC export
than streams during baseflow, but during storms the canopy is a major contributor to stream CDOM  in forests.
Turbidity and CDOM change on different times scales during storm runoff. We developed a method to relate
laboratory water quality measurements directly to in situ UV attenuation. Stream  DOC is correlated with
percent area of wetlands in the watershed and in the absence of wetlands is  correlated with percent area of
farmland. At any given site, stream DOC is inversely correlated with specific conductance,  a reflectance of the
lower concentration of DOC in ion-rich groundwater.

    In our previous work in lakes, we observed large variations among groups  of organisms in their sensitivity
to UVR and that DOC was a strong determinant of UV attenuation. We also expected suspended particles to
have a bigger impact on UV attenuation in streams compared  to lakes, especially during storm runoff. We also
knew that UVR exposure of streams would be reduced in forested areas because of shading  by the canopy. We
now have UV-specific information on these factors for stream ecosystems in our region that can be tested for
generality in other regions.
           The Office of Research and Development's National Center for Environmental Research

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                    Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
    Our next steps  include:  (1) exploring the observed patterns for stream-watershed interactions in other
parts of the watershed; and (2) determining whether shrubs and crop vegetation also contribute to CDOM in
streams during storm runoff. We plan to integrate measurements of biolability and photolability with estimates
of canopy UVR transparency to estimate the turnover of stream DOC (and corresponding oxygen demand)
across the watershed.
           The Office of Research and Development's National Center for Environmental Research

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                     Joint Progress Review for U.S. EPA STAR Grants: Regional-Scale
           Stressor-Response Models and Consequences of Global Change for Aquatic Ecosystems
Question-and-Answer Session with Dr. Bruce Hargreaves

A  One participant questioned an outlier data point on the  graph for canopy transmittance for diffuse
    irradiance.  Dr.  Hargreaves stated  that everything is  equivalent. Direct  light and diffuse light change
    together. Diffuse light varies primarily on the openness of the canopy, whereas direct light depends on
    where the canopy opening is versus where the sun is, the time of day, and which way the steam is oriented.
    He could have said in his presentation that there is a high variability in the direct transmittance. If things
    are equivalent, you get a positive relationship, but there is a great potential  for direct light to be all over the
    map. In reference to the  outlier, that kind of data is not useful without a detailed mapping of where the
    gaps are in the canopy.

A  One participant commented that r2 is meaningful in terms of statistical significant when you have bivariant
    normality (i.e., you have a normal distribution in  any direction). The  reason that the r2 is equal to 0.8716 is
    largely due to the point on the right. The r2 does not have any meaning when virtually all of the data points
    are  clustered in one spot. Dr. Hargreaves  agreed. They find that relationship when they look at their
    wetlands. There is variation around the regression but they also find a  trend. The data shown were  a
    subsampling of their analysis. Dr. Hargreaves stated that he would have to  fill in the gaps for his data if he
    were to compare to the r2 of 0.1825 that Dr. Bridgham reported that had a more even distribution.
           The Office of Research and Development's National Center for Environmental Research

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      Joint Progress Review for U.S. EPA STAR Grants:  Regional-Scale
    Stressor-Response Models and Consequences of Global Change for
                                Aquatic Ecosystems

                                Sheraton National Hotel
                                   900 S Orme Street
                                  Arlington, VA 22204

                                  November 3-4, 2005

                                    Participants List
Rochelle Araujo
U.S. Environmental Protection Agency

Michele Aston
U.S. Environmental Protection Agency

Scott Bridgham
University of Oregon

Rebecca Clark
U.S. Environmental Protection Agency

William Clements
Colorado State University

Noha Gaber
U.S. Environmental Protection Agency

Charles Gallegos
Smithsonian Institution

Iris Goodman
U.S. Environmental Protection Agency

Michael Haire
U.S. Environmental Protection Agency

Bruce Hargreaves
Lehigh University

Robert Howarth
Cornell University

David Hyndman
Michigan State University

Tim Icke
U.S. Environmental Protection Agency
Thomas Johnson
U.S. Environmental Protection Agency

Susan Julius
U.S. Environmental Protection Agency

Joseph Koonce
Case Western Reserve University

Roland Lamberson
Humboldt State University

E. Conrad Lamon III
Duke University

Xuyong Li
Smithsonian Institution

Elias Manolakos
Northeastern University

Scott McMurry
Texas Tech University

Charles Noss
U.S. Environmental Protection Agency

Vladimir Novotny
Northeastern University

Pasky Pascual
U.S. Environmental Protection Agency

Steve Railsback
Humboldt State University

Kenneth Reckhow
Duke University

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Joe Roman
American Association for the Advancement of
  Science - EPA Fellow
U.S. Environmental Protection Agency

Joel Scheraga
U.S. Environmental Protection Agency

Rita Schoeny
U.S. Environmental Protection Agency

Patrick Schoff
University of Minnesota at Duluth

Michael Slimak
U.S. Environmental Protection Agency

Bernice Smith
U.S. Environmental Protection Agency
R. Jan Stevenson
Michigan State University

Dennis Swaney
Cornell University

Rosaura Vega
U.S. Environmental Protection Agency

Hongqing Wang
Florida A&M University

Don Weller
Smithsonian Institution

Robert Whitlatch
University of Connecticut

Katie Wolff
U.S. Environmental Protection Agency

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