&EPA
United States Environmental
Protection Agency
Office of Research
and Development
National Health and Environmental
Effects Research Laboratory
                            Western Ecology Division
                             Research   Update
Corvallis, Oregon 97333
                         EPA/600/F-05/018
                                        September 2005
WED teams up with National Park Service to quantify contaminants in remote places

National parks exist to preserve the
Nation's most beautiful scenery and
pristine ecosystems for the appre-
ciation of future generations. Park
managers can protect parks' plants
and animals from obvious and direct
threats by making and enforcing
rules and regulations, but airborne
pollutants do not recognize laws or
park boundaries.
North America's wild high-altitude,
high-latitude places are particularly
vulnerable to airborne anthropo-
genic contaminants because some
of these pollutants  possess physical
properties that cause them to
accumulate preferentially in the
earth's colder places. This "cold
              With North America's highest mountain, 20,320-foot Mount McKinley, in the background, research-
              ers filter 50-liter water samples in Wonder Lake, Denali National Park.
fractionation" phenomenon is known to occur with some
forms of semi-volatile organic compounds such as
polychlorinated biphenyls (PCBs), hexachlorocyclohexane
(HCHs), and mercury, thus making high-elevation and
high-latitude ecosystems more vulnerable to accumulation
of these pollutants.
The National Park Service (NPS), EPA, and other agen-
cies established a multi-year research effort, the Western
Airborne Contaminants Assessment Project (WACAP), to
determine the risk from airborne pollution to ecosystems
and food webs in western  national parks. Organized and
implemented by NPS's Air Resources Division, the project
involves the cooperation of dozens of scientists from NPS,
EPA, U.S. Geological Survey, USDA Forest Service, and
several universities. Dixon H. Landers, Research Environ-
mental Scientist at the Western Ecology Division (WED)
serves as scientific director for the project as well as
principal investigator of WACAP sediment research. The
project was implemented in 2002 and will conclude in
2007 with an interpretive report. NPS and EPA can use
the WACAP results to evaluate risk to high-elevation and
high-latitude ecosystems in the West from atmospherically
transported contaminants.
The project is documenting the adverse effects of atmo-
spheric transport of anthropogenic pollutants in some of
the nation's most remote, and presumably pristine,
places. Airborne contaminants  can pose a serious health
risk to wildlife and humans. Some toxins tend to "biomag-
nify," that is, small concentrations in air, water, snow, and
plants can  result in larger concentrations higher in the
food web such as in fish and mammals.
                                     WACAP research is centered on eight national parks,
                                     extending from Gates of the Arctic National Park and
                                     Preserve and Noatak National Preserve in arctic Alaska to
                                     Rocky Mountain  National Park in Colorado and Sequoia
                                     National Park in California. At each of these parks, WACAP
                                     researchers have selected two small, high-elevation lake
                                     catchments as locations for sampling to determine which
                                     airborne contaminants have been deposited there.
                                     WACAP scientists are measuring a broad suite of persis-
                                     tent organic pollutants such as PCBs, DDT, DDE, HCHs,
                                     and HCB. Although many of the contaminants have been
                                     banned in the  United States, they are still used in other
                                     parts of the world. Chemicals in current use that are being
                                     assessed include pesticides and flame retardants. Mer-
                                     cury is of special interest and is being analyzed in all
                                     samples except water.
                                                        A WACAP team samples snow on Mount Rainier in Washington.

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                                                                    • WED Research Update	September 2005	Page 2 -
In northern Alaska, such as at Buriel Lake in Noatak National Preserve, WACAP researchers employed aircraft to reach study sites and
to ferry out their samples.
How do these contaminants reach such pristine, protected
places? An important component of WACAP is to examine
the atmospheric transport of chemicals. Already substan-
tive information about the movement of contaminants has
been compiled. Evidence from multiple sources indicates
that both  current-use and banned chemicals are present
in national parks.
Specific examples of the project's findings: dacthal, a
herbicide to control certain weed grasses in a variety of
food crops including those in the tomato, cabbage, and
melon families, is found in much higher concentrations in
Sequoia National Park and Rocky Mountain National Park,
which are near agricultural regions, than in Mount Rainier
National Park or parks in Alaska. By contrast, the project
found hexachlorocyclohexanes, a family of persistent
pesticides banned or phased out by the United States, in
Noatak National Preserve, and in Mount Rainier, Glacier,
Sequoia,  and Rocky Mountain National Parks.
Scheduled field sampling is about two-thirds complete.
Indicators being sampled and their purposes include:
 •  Snow. Measure of direct atmospheric loading of snow
   which  represents 50-90 percent of the annual precipi-
   tation in many alpine sites, with annual sampling in
   2003, 2004, and 2005.
 •  Fish. Provide a direct measurement of food web
   impacts and food web bio-accumulation. In 2003,
   scientists sampled fish from five lakes in Sequoia,
   Rocky Mountain, and Olympic National Parks and in
   2004 they sampled  fish from four lakes  in Alaska.
   Besides contaminant loads, the fish were analyzed for
   endocrine disruption, physiological impairment, and
   other indicators.
 •  Water. Measure the presence of water-soluble chemicals.
 •  Lake sediment. Used to determine the decennial-scale
   histories of contamination by semi-volatile organic
   compounds (SOCs) and metals. Sediments are being
   dated by lead isotope technology, which is useful for
   determining the age of deposits back 200 years.
Sediment analysis provides information on naturally
occurring metals as well as on the accumulation of many
anthropomorphic pollutants.
 • Lichen. Because they are highly sensitive to oxides of
   sulphur and nitrogen, precursors of acidic deposition,
   lichens are widely used environmental indicators.
   Lichen provides a direct measure of food web impact
   and accumulation of metals.
 • Vegetation. Collected at different altitudes in all 19
   parks, provides information on ecosystem exposure
   and comparisons among parks.
 • Moose meat. In Alaska, moose tissue sampled  in 2004
   provides a measure of exposure to people who are
   subsistence hunters there.
Working beside a lake in an Alaskan wilderness park,
researchers dissect a fish to evaluate condition and possible
impacts of contaminants.

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                                                                    • WED Research Update	September 2005 	Page 3-
Protocol for snow sampling requires a great deal of shoveling.

WACAP is analyzing how atmospheric contaminants
reach the national parks. A primary goal of the atmo-
spheric transport component of the study is to illustrate
movement of air masses from all source regions that may
be affecting the western national parks. Air masses from
agricultural regions in California, Mexico, and  Canada
could explain contaminants in some parks. However,
because there is strong and persistent west-east flow of
air masses at the latitude  of all the parks, significant
amounts may be coming from distant western sources in
Asia and Europe.
Scientists are using a model of atmospheric transport to
follow likely trajectories of contaminants back to their
possible sources. By mapping where an airmass has
traveled during the past 10 days, the researchers can see
if it has passed over a region known to be a source of
pollution. The model contains atmospheric data going
back five years.
Data from the project and references to related research
are being posted on the Internet for scientists to use. Two
years of mercury concentration data from snowpack
                                                            samples are currently available. These reveal spatial
                                                            patterns in mercury concentration. In the Alaskan samples,
                                                            the concentrations tend to be quite variable,  a likely effect
                                                            of the shallow depth of snowpacks at low-elevation inland
                                                            sites and relatively large amounts of wind-blown crustial
                                                            material in the snowpack. Along the west coast of the
                                                            Collecting lichen samples from Alaskan tundra.

                                                            contiguous 48 states, most of the parks had a fairly low
                                                            concentration of mercury, while inland sites, Glacier and
                                                            Rocky Mountain National Parks, had a higher concentra-
                                                            tion, presumably related to higher concentrations of
                                                            particulate matter there. Additional data are being posted
                                                            as they become available.
                                                            A WACAP researcher operates the lake sediment sampler.

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                                                                   • WED Research Update	September 2005 	Page 4 -
WACAP is headed by Chris Shaver and Tamara
Blett of the National Park Service's Air
Resources Division in Denver. In addition to
Landers, scientific director and sediment
principal investigator, the project involves the
following principal investigators: Don Campbell,
USGS, snow; Linda Geiser, USDA Forest
Service, vegetation; Daniel Jaffe, University of
Washington, atmospheric transport; Michael
Kent and Carl Schreck, Oregon State University,
fish; Staci Simonich, Oregon State University,
semi-volatile organic compounds; and Howard
Taylor, USGS, metals.
Dr.  Landers is also involved with Canadian
colleagues on a related study being conducted
in Canada's high and remote places. Eventually
data from sediment cores he and colleagues
obtained in high-altitude Canadian lakes will be
compared with data collected in the U.S. parks.
(Contact D.H. Landers, 541-754-4427;
landers.dixon@epa.gov)
A special inflatable raft is used for the sediment coring device, shown being prepared
by Dr. Dixon Landers.
Research   Briefs
Cost-effective benthic sampling protocol for
ecological risk assessment
Habitat-based ecological risk assessments rely, in part, on
knowledge of the relative ecological indicator values of the
habitats at risk. An optimal benthic macrofaunal sampling
is the most cost-effective combination of sample unit size
(area and  depth), sieve mesh size, and number of repli-
cate samples. As part of a programmatic effort to estimate
estuarine habitat values with respect to ecological indica-
tors of benthic macrofaunal community condition, WED
scientists determined the optimum benthic macrofaunal
sampling protocol for detecting differences between four
major habitats (eelgrass, cordgrass, mud shrimp, and
ghost shrimp) in Willapa Bay, Washington. They studied
four important ecological indicators (number of species,
numerical  abundance,  total biomass, and  fish and crab
prey abundance). In their paper, published in the journal
Estuaries, the WED scientists identify the  optimum
sampling protocol and  show how ecological indicator
values for habitats accurately estimated using the
optimum sampling protocol can be used to translate
measured or predicted changes in habitat areas into their
large-scale ecological effects (Contact: Steven Ferraro,
541-867-4048; ferraro.steven@epa.gov).
Reference:  Ferraro, S.P.,  and F.A. Cole. 2004. Optimal benthic
macrofaunal sampling  protocol for detecting differences among
four habitats in Willapa Bay, Washington, USA. Estuaries
27:1014-1025. WED-02-138
Also, see a feature article on this paper in Coastal and Estuarine
Science News, January 2005, Volume 27, Number 6, "Better,
Faster, Cheaper Benthic Sampling" at http://erf.org/cesn/vol27n6.html
              Streamlined fish tissue mercury-sampling analy-
              sis procedure saves money and fish
              When testing fish for mercury, scientists conventionally
              have relied on independent analysis of both filet
              samples and whole fish. Now WED scientists have
              established a filet  biopsy/direct mercury analysis proce-
              dure that is precise and accurate for determining
              mercury concentrations in fish filets and for predicting
              whole-fish mercury concentrations.
              Mercury contamination offish is a widespread phenom-
              enon with potential impact on human health as well as on
              the health of wildlife. Because people eat the muscle
              tissue of fish and because wildlife tend to eat whole fish,
              EPA has an interest in both filet and whole-fish mercury
              concentrations. Evaluation of mercury contamination of
              fish over widespread areas, as is required for regional
              assessments, is hindered by the reluctance of agencies to
              grant collection permits, by the need for freezer space to
              store whole fish, and by labor-intensive preparation of
              whole-fish samples. The mercury sampling method
              evaluated by Research Scientist Spencer Peterson,
              Environmental Statistician  John Van Sickle, and
              colleagues at WED, involves non-lethal 0.25 gm fish filet
              biopsy samples taken  in a  manner not expected to kill the
              fish being analyzed. Using these procedures, the
              researchers studied mercury concentrations in 210 fish of
              various species and sizes from 65 sites across 12 western
              states. The researchers found a highly significant relation-
              ship between mercury levels in the biopsy samples and
              whole fish (r2=0.96). When this tissue sampling and

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analysis procedure is combined with probability-based
sampling, the results can be inferred to an entire population
of water bodies, thus providing regional contamination
estimates with known confidence levels. The study was
recently published in the journal Archives of Environmental
Contamination and Toxicology. Dr. Peterson presented
results of the research at international conferences in
Kyoto, Japan, and Victoria, British Columbia. (Contact: S.A.
Peterson, 541-754-4457; peterson.spencer@epa.gov.)
Reference: Peterson, S.A., J. Van Sickle, R.M. Hughes, J.A.
Schacher, and S.F. Echols. 2005. A biopsy procedure for
determining filet and predicting whole-fish mercury concentration.
Arch. Environ. Contam. Toxicol. 48(1):99-107. WED 04-035


Study aids understanding  of the impact of
increased CO2 on forests
Trees rely on a system of fine roots and associated fungi
to take up required nutrients from the soil. To learn how
fine tree roots respond to  elevated levels of carbon
dioxide, WED scientists recently published results of a
four-year study using ponderosa pine trees grown under
controlled conditions in open-topped chambers. Following
a protocol that enhanced statistical reliability, they applied
three different levels of carbon dioxide (CO2) and  three
different levels of nitrogen to the pines. David Tingey,
Senior Research Plant Pathologist, and his WED
colleagues report in a recent article in the journal  Trees
that elevated levels of CO2 increased the extent that  fine
roots of the ponderosa pines extended into and used new
soil.  Higher CO2, however, had  no effect on associated
root fungi. By contrast, nitrogen fertilizer had no effect on
the growth of fine roots, but nitrogen increased the amount
of mycorrhizal fungi and the extent to which the trees used
areas of the soil containing these fungi. (Contact D.T.
Tingey, 541-754-4621; tingey.dave@epa.gov)
Reference: Tingey, D.T, M.G. Johnson, and D.L. Phillips.  2005.
Independent and contrasting effects of elevated CO2 and
N-fertilization on root architecture in Pinus ponderosa.  Trees
19:43-50. WED-04-020
Two WED interns get Fisheries Society award for
meeting's best student poster
Nancy Raskauskas and Stefanie Orlaineta, undergraduate
interns at WED, received the best student poster award at
the annual meeting of the American Fisheries Society's
Oregon Chapter in February. Study design, data collection,
and analysis for their poster, "Cool Hideaways: Use of
Summer Temperature Refuges by Juvenile Coho Salmon
in the West Fork Smith River," were conducted as part of
their internship with the Division's Freshwater Habitat
Project. Raskauskas is writing her senior honors thesis on
the study for her bachelor's degree at Oregon State
University. The west fork of the Smith River, in coastal
Oregon, has summer temperatures that exceed water
quality criteria, but still supports a robust population of
coho salmon. Pockets of cooler water around tributary
junctions, spring seeps, or in deep pools can provide
thermal refuges where fish congregate to reduce their
                                                                    • WED Research Update	September 2005 	Page 5 -
Nancy Raskauskas, left, and Stefanie Orlaineta with their poster.

exposure to stressful temperatures. The two students
mapped the distribution of the cool refuges during summer
2003, and monitored coho use of refuges and growth in
relation to stream temperature during summer 2004.
These data, combined with other data being collected for
the Freshwater Habitat Project, will be used to identify
factors limiting salmon recovery in coastal Oregon.
(Contact: J.P. Baker 541-754-4517; baker.joan@epa.gov)


New tools for identifying optimal land manage-
ment strategies
Land managers often need to know how to determine the
greatest economic benefit that can be obtained by poten-
tial tradeoffs.  For example, how much timber can be
harvested without causing unacceptable impacts to
wildlife? Resource economists and statisticians have
collaborated with WED Ecologist Nathan  Schumakerto
develop computer modeling techniques that can produce
quantitative answers. By combining biological and
economic models they mathematically predicted strate-
gies that best optimize both results - an outcome that
achieves the maximum for each objective without harming
a competing one. In an article in the Journal of Environ-
mental Economics and Management, the researchers
demonstrate their method by projecting timber production
and species conservation on a forested landscape over a
100-year period.
Their study used PATCH, (Program to Assist in Tracking
Critical Habitat) developed by Dr. Schumaker. PATCH
enables scientists to predict how wildlife populations might
be affected by changes in land use. (Contact N.H. Schu-
maker, 541-754-4658; schumaker.nathan@epa.gov)
Reference: Nalle, D.J., C.A.  Montgomery, J.L. Arthur, S. Polasky,
and N.H. Schumaker. 2004.  Modeling joint production of wildlife
and timber. J. Environ. Econ & Mgt. 48:997-1017. WED-03-069

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                                                                   • WED Research Update	September 2005 	Page 6-
Bringing the complexities of salmon science to elementary
school children
Ian Courier, a graduate student at Oregon State University (OSU) and EPA
student volunteer at WED, is teaching elementary school children the
biology and politics of salmon recovery. Under a National Science Founda-
tion fellowship aimed at providing quality science education at rural schools,
Courier is giving young students hands-on experience with the complexities
of restoring salmon to Pacific Northwest rivers and streams.
In their classroom at Cascades Elementary School in Lebanon, a small city
in Oregon's Willamette Valley, Courier's students hatched salmon from eggs,
raised them to the proper size, and  released them in the nearby South
Santiam River. Eventually, they hope to see some salmon from their class-
room hatchery return as spawning adults. Salmon eggs and incubator
equipment were provided by the Oregon Department of Fish and Wildlife,
local businesses, and WED. Courier is a studenl of Robert Lackey, Senior
Fisheries Biologisl al WED who serves as courtesy and adjuncl professor,
respecfively, in OSU's departments  of Fisheries & Wildlife and Political
Science. In addition to Lackey, a number of WED scientists, including Joe
Ebersole, EPA postdoctoral fellow, and Suzanne Pierson, Geographic
Information Systems expert with Indus Corporation, provide technical advice
for Courier. (Contact: R.T.  Lackey 541-754-4607; lackey.robert@epa.gov)
            The children, including Kolby Peterson, released
            the salmon they had hatched into the South
            Santiam River at a park in Lebanon, Oregon.
Ian Courier, a student volunteer at WED, explains a classroom salmon incubator to sixth graders. Inside (not visible) is a tank and water
filtration system. A vending machine company donated a cold food machine that became the incubator's cooling system.
EPA scientists consult with Russian colleagues
on risk of genetically engineered plants
Jay Reichman, NHEERL postdoctoral fellow at the WED,
and two other EPA scientists visited Russia in May to
collaborate with Russian scientists on development of
tests for risk assessment of genetically engineered plants.
The objective of the project, a partnership with the
Research Centre for Toxicology and Hygienic Regulation
of Biopreparations at the Ministry of Health of the  Russian
Federation, is development of tools for use in ecological
and toxicological risk assessments of plants that have
been genetically altered to produce insecticides. Bob
Frederick, of EPA's National Center for Environmental
Assessment (NCEA), in Washington, D.C., is the EPA
technical manager for this project. Assisting is David Lee,
American Association for the Advancement of Science
Fellow at NCEA.
With funding provided by the Department of State, EPA's
Office of Research and Development (ORD) is estab-
lishing this partner project under the International Science
and Technology Center (ISTC), which was established by
international agreement in November 1992 as a nuclear
nonproliferation program. The ISTC coordinates efforts of
numerous governments, international organizations, and
private sector industries, to provide scientists who have
been employed in weapons development in Russia and
the Commonwealth of Independent States new opportuni-
ties in international partnership.
The ORD scientists' visit to laboratories in Serpukhov,
Russia, is expected to begin the process of refining and
targeting the research direction and to exchange informa-
tion about EPA's research on risks of genetically engi-
neered plants. The three year project will result in a
targeted research program by the Russian scientists that

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                                                                  • WED Research Update	September 2005 	Page 7-
complements work being done in the U.S. and around the
world. ORD scientists will benefit from additional
approaches and methods developed by their counterparts
in Russia, and the Agency will benefit from any additional
tools that are developed. The project will provide an
opportunity to inform scientists in Russia about state of
the art research being conducted by the EPA on geneti-
cally engineered plants. (Contact: R.J. Frederick at NCEA,
202-564-3207; frederick.bob@epa.gov)
Publications  Update
Bryce, S.A., A.J. Woods, J.D. Morefield, J.M. Omernik,
T.R. McKay, G.K. Brackley, R.K. Hall, D.K, Higgins, D.C.
McMorran, K.E. Vargas, E.B. Petersen, D.C. Zamudio,
and J.A. Comstock. 2003.  Ecoregions of Nevada (color
poster with map, descriptive text, summary tables, and
photographs): U.S. Geological Survey, Reston, Virginia.
(map scale 1:1,350,000). WED-02-166
Carr, D.B., D.  White, and A.M. MacEachren. 2005.
Conditioned choropleth maps and hypothesis generation.
Annals of the Association of American Geographers
95(1)32-53. WED-03-111
Chapman, S.S., B.A. Kleiss, J.M. Omernik, T. L. Foit, and
E.O. Murray. 2004. Ecoregions of the Mississippi Alluvial
Plain (color poster with map, descriptive text, summary
tables, and photographs): U.S. Geological Survey,
Reston, Virginia, (map scale  1:1,150,000). WED-04-004
Chapman, S.S., S.A. Bryce, J.M. Omernik, D.G. Dispain,
J. ZumBerge,  and  M. Conrad. 2004. Ecoregions of Wyo-
ming (color poster with map, descriptive text, summary
tables, and photographs): U.S. Geological Survey, Reston,
Virginia, (map scale 1:1,400,000). WED-03-112
Ehrenfeld, J.G. 2004. The  expression of multiple function
in urban forested wetlands. Wetlands 24(4):719-733.
WED 03-002
Eldridge, P.M., J.E. Kaldy, and A.B. Burd. 2004. Stress
response model for the tropical seagrass Thalassia
testudinum: The interactions of light, temperature,
sedimentation, and geochemistry. Estuaries 27:923-937.
WED 03-079
Fairbrother, A., J. Smits, and K. Grasman. 2004. Avian
immunotoxicology. J. Toxicol & Environ.  Health 7(B):105-
137. WED-03-048
Ferraro, S.P.,  and  F.A. Cole. 2004. Optimal benthic
macrofaunal sampling protocol for detecting differences
among four habitats in Willapa Bay, Washington,  USA.
Estuaries 27:1014-1025. WED-02-138
Frick, WE., A.C. Sigleo, and D.T. Specht. 2004 Estimat-
ing nitrogen and tidal exchange in a North Pacific estuary
with EPA's Visual Plumes PDSW model. 12 pages in
Proceedings 3rd International Conf. on Marine Waste
Water Discharge, Catania, Italy September-October,
2004. WED-05-027
Griffith, G.E., S.A.  Bryce, J.M. Omernik, J.A. Comstock,
A.C. Rogers, B. Harrison, S.L. Hatch, and D. Brezanson.
2004. Ecoregions of Texas (color poster with map, descrip-
tive text and photographs): U.S. Geological Survey,
Reston, Virginia, (map scale 1:2,150,000).  WED-04-152
Johnson, J.B. 2005. Hydrogeomorphic wetland profiling:
an approach to landscape and cumulative impacts
analysis. Environmental Monitoring and Assessment
Program. EPA/620/R-05/001 52 pages plus appendix.
WED-05-056
Kahl, J.H., J.L. Stoddard, R. Haeuber, S.G.  Paulsen, R.
Birnbaum, F.A. Deviney, J.R. Webb, W Sharpe, C.T.
Driscoll, AT. Herlihy, J.H. Kellogg, P.S. Murdoch, K. Roy,
K.E. Webster, and N.S. Urquhart. 2004. Have U.S.
surface waters responded to the 1990 Clean Air Act
Amendments? Environmental Science & Technology
38:484A-490A. WED-04-116
Kentula, M.E., S.E. Gwin, and S.M. Pierson. 2004.
Tracking changes in wetlands with urbanization: sixteen
years of experience in Portland, Oregon, USA. Wetlands
24(4):734-743. WED-02-187
Kincaid, T.M., D.P. Larsen, and N.S. Urquhart. 2004. The
structure of variation and its influence on the estimation of
status: Indicators of Condition of the Lakes in the North-
east, U.S.A. Environ. Mont. Assess. 98:1-21. WED-02-172
Lackey, R.T.,  2005. Economic growth and salmon recovery:
an irreconcilable conflict? Fisheries 30(3)30-32. WED 05-026
Lee, E.H., D.T. Tingey, PA. Beedlow, M.G. Johnson, and
R.B. McKane. 2004. A spatial analysis of fine-root
biomass from stand data in the Pacific Northwest. Can. J.
For. Res. 34: 2169-2180. WED 03-169
Meengs, C.C., and R.T. Lackey. 2005. Estimating the size
of historical Oregon salmon runs. Reviews in Fisheries
Science 13:51-66. WED-05-024
Olszyk, D.M., C.A. Burdick, T.G. Pfleeger, E.H. Lee, and
L.S. Watrud. 2004. Assessing the risks to non-target
terrestrial plants from herbicides. J. Agric. Meteorol.
60(4):221-242. WED-04-157
Olszyk, D., M. Johnson, D. Tingey, G. King, M. Storm, and
M. Plocher. 2003. Effects of carbon dioxide  and ozone on
growth and biomass allocation in Pinus ponderosa.
Ekologia (Bratislava) 22(sup.1):265-276. WED-02-164
Perakis, S.S., J.E. Compton, and L.O. Hedin. 2005.
Nitrogen retention across a gradient of 15N additions to an
unpolluted temperate forest soil in Chile. Ecology 86(1):
96-105.
Peterson, S.A., J. Van Sickle, R.M. Hughes, J.A.
Schacher, and S.F. Echols. 2005. A biopsy procedure for
determining filet and  predicting whole-fish mercury
concentration. Arch. Environ. Contam. Toxicol. 48(1):99-
107. WED 04-035

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                                                                 • WED Research Update	September 2005 	Page 8 -
    United States Environmental Protection Agency
    Office of Research and Development
    National Health and Environmental Effects Research Laboratory
    200 SW 35th Street
    Corvallis, OR 97333-4996
                       PRESORTED STANDARD
                       US POSTAGE PAID
                       CORVALLIS, OR
                       Permit No. G-35
    Western  Ecology Division
    Research  Update
Tausz, M., D.M. Olszyk, S. Monschein, and D.T. Tingey.
2004. Combined effects of CO2 and O3 on antioxidative
and photoprotective defense systems in needles of
ponderosa pine. Biologia Plantarium 48 (4):543-548.
WED-04-073
Thayer, G.W., and M.E. Kentula. 2005. Coastal restoration:
where have we been, where are we now, and where should
we be going. J. Coastal Res. 40(SI):1-5. WED-04-180.
Thorson, T.D., S.A. Bryce, D.A. Lammers, A.J. Woods, J.M.
Omernik, P. Kagan, D.E. Pater, and J.A. Comstock. 2003.
Ecoregions of Oregon (color poster with map, descriptive text,
summary tables, and photographs): U.S. Geological Survey,
Reston, Virginia, (map scale 1:1,500,000). WED-03-019.
Tingey, D.T., D.L. Phillips, M.G. Johnson, P.T. Rygiewicz,
PA. Beedlow,  and WE. Hogsett. 2005. Estimates of
Douglas-fir fine root production and mortality from minirhi-
zotrons. For. Ecol. & Mgt.  204:359-370. WED-04-156
Tingey, D.T., M.G. Johnson, and D.L. Phillips. 2005.
Independent and contrasting effects of elevated CO2 and
N-fertilization on root architecture in Pinus ponderosa.
Trees 19:43-50. WED-04-020
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