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Ecological Exposure Research Division Publications: 1999

This page lists publication titles, citations and abstracts produced by NERL's Ecological Exposure Research Division for the year 1999, organized by Publication Type. Your search has returned 37 Matching Entries.

See also Ecological Exposure Research Division citations with abstracts: 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008

Technical Information Manager: Linda Ransick - (513) 569-7395 or ransick.linda@epa.gov

		Presented/Published
BOOK CHAPTER	Asbestos in Drinking Water Performance Evaluation Studies	12/01/1999

Collins, G. B., P. W. Britton, E. J. Chatfield, P. J. Clark, AND K. A. Brackett. Asbestos in Drinking Water Performance Evaluation Studies. M.E. Beard, H.L. Rook (ed.), Advancements in Environmental Measurement Methods for Asbestos. American Society for Testing and Materials, West Conshohocken, PA, STP 1342:273-287, (1999).
Abstract:	Performance evaluations of laboratories testing for asbestos in drinking water according to USEPA Test Method 100.1 or 100.2 are complicated by the difficulty of providing stable sample dispersions of asbestos in water. Reference samples of a graduated series of chrysotile asbestos concentrations dispersed in glass-distilled water were prepared in December of 1989 to address this concern. Sealed glass ampules, containing the reference dispersions, were sent to volunteer asbestos testing laboratories. The number of participating labs varied from 33 to 50. The data reported here was compiled from the four most recent test rounds performed. Statistical analysis of data from the volunteer laboratories indicate that further work is needed to develop asbestos reference samples that produce data with less variability. Details of the preparation of the samples, laboratory analytical procedures and statistical analysis of the results are presented, along with a discussion of issues suggested by the data.

JOURNAL	Spatial Patterns and Ecological Determinants of Benthic Algal Assemblages in Mid-Atlantic Streams, USA	06/01/1999

Pan, Y., R. J. Stevenson, B. H. Hill, A. T. Herlihy, AND P. R. Kaufmann. Spatial Patterns and Ecological Determinants of Benthic Algal Assemblages in Mid-Atlantic Streams, USA. JOURNAL OF PHYCOLOGY 35(3):460-468, (1999).
Abstract:	We attempted to identify spatial patterns and determinants for benthic algal assemblages in Mid-Atlantic streams. Periphyton, water chemistry, stream physical habitat, riparian conditions, and land cover/use in watersheds were characterized at 89 randomly selected stream sites in the Mid-Atlantic region. Cluster analysis (TWINSPAN) partitioned all sites into six groups based on diatom species composition. Stepwise discriminant function analysis indicated that these diatom groups can be best separated by watershed land cover/use (percentage forest cover), water temperature, and riparian conditions (riparian agricultural activities). However, the diatom-based stream classification did not correspond to Omernik's ecoregional classification. Algal biomass measured as chl a can be related to nutrients in habitats where other factors do not constrain accumulation. A regression tree model indicated that chl a concentrations in the Mid-Atlantic streams can be best predicted by conductivity, stream slope, total phosphorus, total nitrogen, and riparian canopy coverage. Our data suggests that broad spatial patterns of benthic diatom assemblages can be predicted both by coarse-scale factors, such as land cover/use in watersheds, and by site-specific factors, such as riparian conditions. However, algal biomass measured as chl a was less predictable using a simple regression approach. The regression tree model was effective for showing that ecological determinants of chl a were hierarchical in the Mid-Atlantic streams.

JOURNAL	Effects of Extenders and Time of Storage Before Freezing on Motility and Fertilization of Cryopreserved Muskellunge Spermatozoa	11/01/1999

Ciereszko, A., K. Dabrowski, S. A. Christ, G. P. Toth, AND F. Lin. Effects of Extenders and Time of Storage Before Freezing on Motility and Fertilization of Cryopreserved Muskellunge Spermatozoa. TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY 128(3):542-548, (1999).
Abstract:	The usefulness of five extenders for cryopreservation of muskellunge semen was studied in fertlization trials and computer-assisted semen analyses (CASA) of postthaw sperm motility. The effect of pre-freezing storage time before cryopreservation on success of cryopreservation was also analyzed. A 50% fertilization rate (compared with fresh semen) of the extender containing 10% demethyl sulfoxide (DMSO) in seminal-plasma-mimicking medium (SPMM) supplemented by 10% egg yolk was significantly higher than in extenders consisting of 10% DMSO, 0.6M sucrose, and 10% egg yolk or 20% glycerol and 0.3 M glucose. Spermatozoa cryopreserved with DMSO-SPMM-egg yolk extender had the highest values of straight-line velocity and linearity of movement. Significantly lower fertilizing ability and curvilinear velocity were found for semen specimens stored on ice for 5 h before freezing compared with specimens stored for 1 h. Although spermatozoa cryopreserved with extender containing 10% methanol had only traces of motility or nomotility at all after thawing, fertilization trials indicated that their fertilizing ability was preserved. Despite a lack of motility after thawing, these spermatozoa could have been activated by egg components, thus indicating that they could have been motile during fertilization. This possibility suggests that the motility pattern of muskellunge spermatozoa may be influenced during fertilization by egg components.

JOURNAL	Male Reproductive Effects of Solvent and Fuel Exposure During Aircraft Maintenance	05/06/1999

LeMasters, G. K., D. M. Olsen, J. H. Yiin, J. E. Lockey, R. Shukla, S. G. Selevan, S. M. Schrader, G. P. Toth, D. P. Evenson, G. B. Huszar, AND G. B. Husar. Male Reproductive Effects of Solvent and Fuel Exposure During Aircraft Maintenance. REPRODUCTIVE TOXICOLOGY 13(3):155-166, (1999).
Abstract:	Few studies have addressed the effects of mixed, low level exposures to complex mixtures on a man's reproductive potential. In this prospective study, each subject was evaluated prior to first exposure and at 15 and 30 weeks after exposures had begun. A total of 50 men working on aircraft maintenance at an Air Force installation were included in the study. In addition, eight unexposed men were concurrently sampled. Industrial hygiene (IH) sampling and expired breath samples were collected for jet fuel as measured by total napthas, benzene--a component of jet fuel, 1,1,1-trichloroethane, methyl ethyl ketone, xylenes, toluene and methylene chloride. Sperm production, structure and function (sperm concentration, sperm motion, viability, morphology, morphometrics and stability of sperm chromatin) were evaluated. Exposures were low. All mean IH measures were below 6 ppm, which is less than 10% of the Occupational Safetyand Health Administration standard for all chemicals except benzene. Sheet metal workers had the highest mean breath levels for both total solvents (24 ppb) and fuels (28.3 ppb). For most sperm measures, mean values remained in the nbormal range throughout the 30 weeks of exposure. When jobs were analyzed by exposure groups, some adverse changes were observed. The paint shop group had a significant decline in motility of 19.5% at 30 weeks. Internal dose measures, however, did not show a significant association with spermatogenic changes.

JOURNAL	Hypothesis Testing With the Similarity Index	12/01/1999

Leonard, A. C., S. E. Franson, V. S. Hertzberg, M. K. Smith, AND G. P. Toth. Hypothesis Testing With the Similarity Index. MOLECULAR ECOLOGY 8(12):2105-2114, (1999).
Abstract:	Mulltilocus DNA fingerprinting methods have been used extensively to address genetic issues in wildlife populations. Hypotheses concerning population subdivision and differing levels of diversity can be addressed through the use of the similarity index (S), a band-sharing coefficient, and many researchers construct hypothesis tests with S based on the work of Lynch. It is shown in the present study, through mathematical analysis and through simulations, that estimates of the variance of a mean S based on Lynch's work are downwardly biased. An unbiased alternative is presented and mathematically justified. It is shown further, however, that even when the bias in Lynch's estimator is corrected, the estimator is highly imprecise compared with estimates based on an alternative approach such as "parametric bootstrapping" of allele frequencies. Also discussed are permutation tests and their construction given the interdependence of Ss which share individuals. A simulation illustrates how some published misuses of these tests can lead to incorrect conclusions in hypothesis testing.

JOURNAL	Land Treatment of PAH-Contaminated Soil: Performance Measured By Chemical and Toxicity Assays	10/22/1999

Sayles, G. D., C. M. Acheson, M. J. Kupfler, Y. Shan, Q. Zhou, J. R. Meier, L. W. Chang, AND R. C. Brenner. Land Treatment of PAH-Contaminated Soil: Performance Measured By Chemical and Toxicity Assays. ENVIRONMENTAL SCIENCE & TECHNOLOGY 33(23):4310-4317, (1999).
Abstract:	The performance of a soil remediation process can be determined by measuring the reduction in target soil contaminant concentrations and by assessing the treatment's ability to lower soil toxicity. Land treatment of polycyclic aromatic hydrocarbon (PAH)-contaminated soil from a former wood-treating site was simulated at pilot scale in temperature-controlled soil pans. Nineteen two- through six-ring PAHs were monitored with time (initial total PAHs - 2800 mg/kg). Twenty-five weeks of treatment yielded a final total PAH level of 1160 mg/kg. Statistically significant decreases in concentrations were seen in total, two-, three-, and four-ring PAHs. Carcinogenic and five- and six-ring PAHs showed no significant change in concentration. Land treatment resulted in significant toxicity reduction based on root elongation, Allium chromosomal aberration, and solid-phase Microtox bioassays. Acute toxicity, as measured by the earthworm survival assay, was significantly reduced and completely removed. The Ames spiral plate mutagenicity assay revealed that the untreated soil was slightly mutagenic and that treatment may have reduced mutagenicity. The variety of results generated from the chemical and toxicity assays emphasize the need for conducting a battery of such tests to fully understand soil remediation processes.

PRESENTATION	Evaluation of Characteristic Spatial and Temporal Scales for Measures of Physical Habitat, Water Chemistry, and Biological Condition in Streams	08/01/1999

Flum, T., S. M. Cormier, R. Fan, B. Subramanian, AND G. Senay. Evaluation of Characteristic Spatial and Temporal Scales for Measures of Physical Habitat, Water Chemistry, and Biological Condition in Streams. Presented at GIS Conference, Cincinnati, OH, Aug. 1999.
Abstract:	There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION	The Association of Land Use/Land Cover and Nutrient Levels in Maryland Streams	08/15/1999

Senay, G., A. Liu, S. M. Cormier, B. Subramanian, AND S. Y. Tong. The Association of Land Use/Land Cover and Nutrient Levels in Maryland Streams. Presented at International Congress on Ecosystem Health: Managing for Ecosystem Health, Sacramento, CA, August 15-20, 1999.
Abstract:	Anthropogenic nonpoint sources of nutrients are known to cause accelerated eutrophication of estuaries. The Chesapeake Bay is one of the world's largest estuaries exhibiting the eutrophication problem caused by pollution from various land use activities. The sources contributing to this include streams, areal deposition and direct loading to the bay. This study focused on the sources to the stream. Spatial and statistical analyses were conducted to investigate the relationships between field measurements of stream chemistry (nitrate, sulfate, dissolved organic carbon, etc.) habitat and satellite-derived land use maps for the state of Maryland. Hydrologic Unit Code (HUC) watershed boundaries (8-digit) were used as the basis for grouping stream chemistry data. Arc/Info, a leading GIS software, was used to compute percent land cover area (forest land, crop land, pastureland, etc.) within a HUC. The percent agricultural lands (crop, pasture, etc.) were positively correlated (significant) with nitrate (NO3) and dissolved organic carbon (DOC) while percent forest cover was negatively correlated (significant) with NO3 and DOC. These resutls were in agreement with other reports and with the fundamental understanding of the role of the land cover types in chemical loadings to streams. The percent forest and percent agriculture land use displayed opposite signs in the correlation matrix with stream chemistry data including sulfate and pH variables. Although there was a negative correlation between percent forest and NO3 in the streams, this was likely due to a reduction in the area occupied by agricultural lands, a predominant source of NO3, not the amount of forest area per se. This was further supported by the presence of a negative correlation between percent forest area and percent agricultural area. These analyses indicated that agriculture was the main source of NO3 pollution in Maryland streams. The next step in this study is investigation of the point sources leading to the chemical loadings to the streams.

PRESENTATION	Assessing Fish Tissue Contamination on a Regional Scale	08/15/1999

Lazorchak, J. M., F. H. McCormick, A. T. Herlihy, T. R. Henry, S. P. Bradbury, AND R. B. Yeardley Jr. Assessing Fish Tissue Contamination on a Regional Scale. Presented at International Congress on Ecosystem Health: Managing for Ecosystem Health, Sacramento, CA, August 15-20, 1999.
Abstract:	The selection of target fish species for assessing the extent of fish tissue contaminants is a critical consideration in regional stream surveys such as the Environmental Monitoring and Assessment Program (EMAP). The ideal species would be widely distributed and common, bioaccumulate chemicals of concern, and be consumed by piscivorous wildlife. In first- to third- order streams, small, short-lived forage fish, i.e., minnows (F. Cyprinidae), darters (F. Percidae), and sculpins (F. Cottidae), are more widely distributed and found in greater numbers than species whose adults grow to large size, i.e., suckers (F. Catostomidae), trout (F. Salmonidae), bass and sunfish (F. Centrachidae) and carp (F. Cyprinidae). The small forage fish are less mobile, often occur in larger numbers, and generally have smaller home ranges than the bigger fish. Thus, small forage fish usually provide a sufficient sample for chemical analysis and may represent an approximation of the "site average" of accumulated tissue contaminants. Analysis of fish collections from the 1993-94 Mid-Atlantic Highlands Assessment (MAHA) showed that small forage fish were more widely distributed than larger species. Regional assessments of fish tissue contaminants were made for Chlordane, DDT and Metabolites (DDT), Dieldrin, Endrin, Hexachlorobenzene, Mercury, and Polychlorinated Biphenyls (PCBs). Using the percent of stream miles exceeding the wildlife effects thresholds as a basis for comparison, regional assessments based on small, forage fish were not significantly different from regional assessments using large fish. Small, short-lived fish may, therefore, be an excellent choice as target species for conducting regional fish tissue studies and wildlife problem formulations.

PRESENTATION	Expression of Rainbow Trout P450 Mrna in Response to Mixtures of B[a]p, Cadmium, and Estradiol	11/13/1999

Lattier, D. L., J. S. McClain, AND J. T. Oris. Expression of Rainbow Trout P450 Mrna in Response to Mixtures of B[a]p, Cadmium, and Estradiol. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	A great deal of uncertainty exists regarding the response of biological indicators of exposure to mixtures of chemical stressors. Enzymatic transformation systems that are exposed to xenobiotic insult may interact unpredictably when more than one stressor is present. In particular, monoxygenase and related enzymes may be down- or up-regulated, depending on the mix and concentration of chemicals present. The objectives of this study were to screen representatives of broad chemical classes for interactive effects on the monoxygenase P450 system, represented by the CYPIA1 gene. The chemicals benzo(a)pyrene, cadmium and estradiol were administered intraperitoneally, separately and in mixtures at various concentrations, following a block design, in sexually immature rainbow trout (O. mykiss). After 24 hours of exposure, liver tissue was removed and total RNA extracted for use in Reverse Transcription PCR. A set of PCR primers specific to rainbow trout were used to detect mRNA for CYPIA1. Analysis of relative mRNA expression revealed a 50% decrease in BaP-stimulated CYPIA1 by either estradiol or cadmium. When all three chemicals were combined, there was a further decrease of CYPIA1 mRNA expression to levels beyond those observed for estradiol plus BaP or cadmium plus BaP. The expression level observed, following the ternary exposure, represented approximately 10% of the expression stimulated by BaP alone. These combinations of chemical stressors represent plausible mixtures that may affect teleost physiological responses in ways not predicted by single chemical exposure systems. Moreover, regional evaluations of biological indicators may be skewed by false negatives when evaluating field populations for exposure to chemical stressors. The development of biological indicators of exposure will benefit from using chemical mixtures in exposure systems by identifying unrecognized mechanisms and interactions.

PRESENTATION	Sensitivity Analysis of the Application of Chemical Exposure Criteria for Comparing Sites and Watersheds	11/14/1999

Fulk, F. A. AND S. M. Cormier. Sensitivity Analysis of the Application of Chemical Exposure Criteria for Comparing Sites and Watersheds. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	A methodology was developed for deriving quantitative exposure criteria useful for comparing a site or watershed to a reference condition. The prototype method used indicators of exposures to oil contamination and combustion by-products, naphthalene and benzo(a)pyrene metabolites, sampled from white suckers and common carp in the Eastern Cornbelt Plains Ecoregion of Ohio. Sites were selected by two sampling schemes. First through second order stream sites were selected by an intensified probability-based sampling design developed by the Environmental Monitoring and Assessment Program (EMAP). For larger streams, reference sites were selected by Ohio EPA ecologists. Numerical exposure criteria were determined by an empirical approach, the 95th percentile derived from ranked data. Binomial probabilities based on the number of fish exceeding the exposure criteria at a site and the number of fish sampled at a site were used to determine contamination. The percentile selected to represent the exposure criteria, i.e., 90th, 95th, 99th and the level of significance in determining contamination at a site, i.e., 1% vs 5%, may impact the final assessment. An analysis of the sensitivity of the final assessment to the selection of percentile and level of significance was conducted. Correlation of the contaminated sites with NPDES discharges and levels of contaminants in the water and sediment were used to confirm the presence of contamination at the designated sites.

PRESENTATION	Coordinating, Communicating and Performing Complex Research That Identifies Vulnerable Stream Ecosystem in the Mid-Atlantic Region	11/14/1999

Flum, T., S. M. Cormier, F. A. Fulk, AND B. Subramanian. Coordinating, Communicating and Performing Complex Research That Identifies Vulnerable Stream Ecosystem in the Mid-Atlantic Region. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	The USEPA's Regional Vulnerability Assessment (ReVA) program was created to advance the scientific basis for protecting vulnerable ecosystems at a regional scale. As a first step, the ReVa program will coordinate, communicate and perform complex research that will identify vulnerable stream and forest ecosystems in the mid-Atlantic region. The streams component of the ReVA program is building upon a list of stressors identified for the mid-Atlantic region that include such concerns as stream acidification, habitat modification including hydrologic alteration, toxic organic compounds and metals, nuisance algal blooms, exotic species, and fisheries management. One objective of the ReVa program is to develop maps of the important stressors. These maps will be generated using GIS tools including remote sensing and interpolation techniques such as geostatistical models, multivariate statistical models, and first principles models. Statistical models, for example, were used to examine relationships between stressors and aquatic receptors based on ecological, epidemiological, and statistical inferences. To illustrate the ReVa approach, examples are presented for mine drainage and statistical modeling of nurient and polyaromatic hydrocarbon exposures. Ultimately, models will be developed to project changes in the important concerns relevant to streams so that future conditions and risks can be estimated at the regional scale.

PRESENTATION	Identification of the Cause of Biological Impairment in the Little Scioto River, Ohio	11/12/1999

Cormier, S. M., E. C. Lin, M. R. Millward, D. E. Williams, B. Counts, D. Altfater, AND R. Sanders. Identification of the Cause of Biological Impairment in the Little Scioto River, Ohio. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	The Little Scioto River in Ohio was selected as a case study for the development of a causal framework which combined measures of community assemblages, habitat quality and biomarkers in an ecological and diagnostic approach. Fish assemblage condition was measured with the Index of Biotic Integrity (IBI), macroinvertebrate assemblage with the Invertebrate Community Index (ICI), and habitat quality with the Qualitative Habitat Evaluation Index (QHEI). Ambient levels of potential chemical stressors were determined from sediment and water chemistry analyses. Exposures to a variety of contaminants were estimated in two fish species, white suckers (Catostomus commersoni) and common carp (Cyprinus carpio) using five biochemical assays. Biomarker levels of fish and index scores from potentially stressed sites were compared with samples taken from upstream "least impacted" sites and with a calculated regional exposure criteria or Ohio's aquatic life use criteria. Longitudinal analysis of community indices showed impairment, physical habitat measurements suggested possible causes, sediment and water chemistry showed presence of contaminants, and biomarkers proved exposure. Characteristics of the fish and macroinvertebrate assemblages were consistent with ecological and biological theory and analogues to biological signatures at other contaminated sites. Responses to two distinct types of stressors, habitat modification and complex toxics, were found. Combining indicators of different types in a causal framework provided more information, and made a stronger case for implied stressor sources than any single indicator.

PRESENTATION	Nutrient Uptake and Community Metabolism in Streams Draining Harvested and Old Growth Watersheds: A Preliminary Assessment	10/27/1999

Hill, B. H. AND F. H. McCormick. Nutrient Uptake and Community Metabolism in Streams Draining Harvested and Old Growth Watersheds: A Preliminary Assessment. Presented at Symposium on Ecosystem Management Research in the Ouachita and Ozark Mountains, Hot Springs, AZ, October 26-28, 1999.
Abstract:	The effect of timber harvesting on streams is assessed using two measures of ecosystem function: nutrient ad community metabolism. This research is being conducted in streams of the southern Appalachian Mountains of North Carolina, the Ouachita Mountains of Arkansas, the Cascade Montains of Oregon, and the redwood forests of northern California, in order to understand similarities and differences among stream ecosystem responses to timber harvesting across diverse geographic regions. Data from Cedar and Peacock Creeks in the redwood forest are used to illustrate the principles and usefulness of measuring stream ecosystem function for assessing watershed disturbances. Streams draining logged watersheds had smaller dominant substrate size and more sand and fine sediments in the channel. Nutrient uptake (NH4+1, PO4-3) and community metabolism (primary productivity, respiration, P:R, net daily metabolism) were measured in streams draining old-growth (Cedar Creek) and harvested (Peacock Creek) watersheds. Phosphate uptake length was significantly shorter in Cedar Creek than in Peacock Creek. Ammonium uptake length was not significantly different in these streams. Preliminary analyses of stream metabolism suggest that primary productivity is greater in streams draining logged watersheds, but community respiration is greater in stream draining old-growth watersheds, resulting in substantial differences in P:R and NDM.

PRESENTATION	Blood Proteins and Dna Adducts of Atrazine in Peromyscus Leucopus as Biological Indicators of Triazine Herbicide Exposures in the Environment	03/14/1999

Reddy, T. V., F. B. Daniel, G. P. Toth, H. Wang, AND B. E. Wiechman. Blood Proteins and Dna Adducts of Atrazine in Peromyscus Leucopus as Biological Indicators of Triazine Herbicide Exposures in the Environment. Presented at Society of Enviromental Toxicology and Chemistry, New Orleans, LA, March 14, 1999.
Abstract:	There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION	Development of Single Cell Gel (Scg) Assay for Monitoring Contamination of Aquatic Ecosystems	03/28/1999

Chang, L. W., J. R. Meier, AND G. P. Toth. Development of Single Cell Gel (Scg) Assay for Monitoring Contamination of Aquatic Ecosystems. Presented at Environmental Mutagen Society, Washington, D.C, March 28, 1999.
Abstract:	There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION	The Extent of Mine Drainage Into Streams of the Central Appalachian and Rocky Mountain Regions	04/06/1999

Hill, B. H., J. M. Lazorchak, A. T. Herlihy, F. H. McCormick, M. B. Griffith, P. Haggerty, B. J. Rosenbaum, AND A. Liu. The Extent of Mine Drainage Into Streams of the Central Appalachian and Rocky Mountain Regions. Presented at The EMAP Symposium on Western Ecological Systems, San Francisco, CA, April 6-8, 1999.
Abstract:	Runoff and drainage from active and inactive mines are contaminating streams throughout the United States with acidic and metal contaminated waters and sediments. The extent of mining impacts on streams of the coal bearing region of the Central Appalachians and the metal bearing regions of the Rocky Mountains were assessed by three approaches. First, chemistry data from streams sampled by the USEPA's Environmental Monitoring and Assessment Program (EMAP) and Regional EMAP (REMAP) were used to classify streams based on acid neutralizing capacity (ANC), sulfate, metals, and chloride concentrations of the water. High sulfate and metal concentrations served as excellent indicators of mine drainage impacts in the watersheds. In the second approach, we determined the extent of mining activity within each U.S. Geological Survey 8-digit hydrologic catalog unit within the study regions and its proximity to streams based on classified thematic mapper (TM) satellite imagery and the USEPA's River Reach File Version 3 (RF3) data. Our third approach, using biological data collected from the EMAP and REMAP streams, looked at the correlation of these data with the stream chemical classification, and estimated the extent of mining impact based on biotic indices and microbial respiration. The stream chemistry approach estimated that about 9% of the stream length in the regions were impacted by mine drainage. The TM approach estimated that 7% of the stream length in the regions were vulnerable to mining impacts. The stream biota indicated that the extent of mining impacts to streams might be as high as 50% of the stream length in the regions.

PRESENTATION	An Exploratory Approach to Assessing the Influences of Environmental Factors on Fish Community Distribution and Health	08/15/1999

Tong, S. Y. AND S. M. Cormier. An Exploratory Approach to Assessing the Influences of Environmental Factors on Fish Community Distribution and Health. Presented at International Congress on Ecosystem Health: Managing for Ecosystem Health, Sacramento, CA, August 15-20, 1999.
Abstract:	The Chesapeake Bay is one of the most productive systems in the world. It supports a variety of aquatic resources of flora and fauna. However, for the past 350 years and especially in the last two to three decades, there has been substantial deterioration of the natural resources. Many species of submerged aquatic vegetation and benthic invertebrates have been extirpated. Commercial harvests of fish, crabs and shellfish have also declined. The cause of this ecological phenomenon is unknown, although it may be related to nutrient enrichment. To restore the Bay area and to conserve the fish resources, the causal relationships between the environmental stressors and the distribution and health of the fish communities must be understood. This research project adopts an integrated methodology involving the use of multi-variate ordination, statistical and geographical information systems (GIS) techniques to explore the intricate effects of various environmental factors on fish. Multi-variate ordination techniques are useful exploratory tools to help elucidate the latent environmental relationships and to define specific biocriteria. GIS is a spatial analytical technique for identifying spatial relationships. In this project, a non-metric multi-dimensional scaling ordination technique is employed in conjunction with other statistical techniques and ArcView GIS to reveal the relationships between a suite of environmental factors (including in-stream habitat characteristics and neighboring land use) and nitrate levels and fish conditions (such as the Index of Biological Integrity, % of abnormalities, the presence and absence values of fish species) in the riverine system. The results showed that land use is significantly related to nutrient loading, and each is related to the distribution and health of the fish communities.

PRESENTATION	Bioassessment of Wadeable Streams in USEPA Region 8, Using the EMAP Chemistry Indicator, Benthic Macroinvertebrate Indicator, Water Column Toxicity Tests, and Sediment Toxicity Tests	04/06/1999

Klemm, D. J., A. T. Herlihy, J. M. Lazorchak, M. Smith, AND W. T. Thoeny. Bioassessment of Wadeable Streams in USEPA Region 8, Using the EMAP Chemistry Indicator, Benthic Macroinvertebrate Indicator, Water Column Toxicity Tests, and Sediment Toxicity Tests. Presented at The EMAP Symposium on Western Ecological Systems, San Francisco, CA, April 5-9, 1999.
Abstract:	Almost 95% of the mineralized portion of the Rocky Mountains are contained in the Southern Rockies Ecoregion. For the past century, extensive mining of metals has occurred in this area. Runoff and drainage from both active and inactive mining sites have contaminated waters and sediments. The U.S. EPA conducted a probability survey as part of its Environmental Monitoring and Assessment Program (EMAP), Regional Environmental Monitoring and Assessment Program (R-EMAP) in the Colorado portion of the Southern Rockies in 1994 and 1995. The survey targeted second-fourth order wadeable streams as represented on USGS 1:100,000 scale maps. Using data from this study, the potential impact of mining on stream condition was assessed using three approaches. The first approach used water chemistry data collected from the survey to classify streams based on Acid Neutalizing Capacity (ANC), sulfate, chloride, and metal concentrations. In the second assessment approach, water column samples and sediment samples were collected at the same sites as the chemistry samples. Ceriodaphnia dubia and Pimephales promelas 48-hour tests were conducted on the water column samples and the 7-day survival and growth tests using Hyalella azteca were conducted on the sediment samples. The third approach used stream macroinvertebrate assemblages collected at the sample sites to quantify the EMAP multimetric, Stream Benthos Integrity Index (SBII) method. High sulfate and metal concentrations in these sites served as an excellent indicator of mine drainage impacts in the watershed. The results indicated that almost all of the sites with impacted benthos and water column toxicity occurred in sites classified as mine drainage impacted by water chemistry. The stream chemistry data estimated that 28% of the stream miles in the target population were impacted by mine drainage. The toxicity data estimated that 9% of the stream miles in the target population had stream water toxic to aquatic organisms. The SBII scores indicated that 8% of the stream miles in the target population had impaired benthic invertebrate biotic integrity.

PRESENTATION	Stream Bioassessments and How Taxonomic Resolution Affects Our View of the World: An Example from the Mid-Atlantic Highlands	05/25/1999

Waite, I. R., D. J. Klemm, D. P. Larsen, AND A. T. Herlihy. Stream Bioassessments and How Taxonomic Resolution Affects Our View of the World: An Example from the Mid-Atlantic Highlands. Presented at North American Benthological Society, Duluth, MN, May 25-28, 1999.
Abstract:	During late spring 1993-1995, the USEPA's Environmental Monitoring and Assessment Program (EMAP) sampled wadeable streams in the mid-Atlantic region of the U.S. for a variety of physical, chemical, and biological indicators of environmental condition. A representative set of about 450 study sites was selected. At each site, macroinvertebrates were collected from nine equidistant transects along the study reach using a modified kicknet. Macroinvertebrates from riffles and pools were composited separately for the site yielding over 850 samples, and each composite sample was enumerated using a 300-organism count. The database includes approximately 1100 taxa in 200 families. Percent similarity and ordination analyses were used to evaluate patterns among the insect assemblages from multiple ecoregions at differing levels of taxonomic resolution. Using a subset of data, percent similarity among ecoregion classes showed no differences among family, genus, and species (lowest taxon) level identification. However, ordination of genus or species level identification produced greater spread of sites than family level along a gradient of stream size. These data reveal the importance of the added information from genus or species level identification when comparing among sites.

PRESENTATION	Diatom Indices of Stream Ecosystem Conditions: Comparison of Genus Vs. Species Level Identifications	05/26/1999

Hill, B. H., R. J. Stevenson, AND Y. Pan. Diatom Indices of Stream Ecosystem Conditions: Comparison of Genus Vs. Species Level Identifications. Presented at North American Benthological Society, Duluth, MN, May 25-28, 1999.
Abstract:	Diatom assemblage data collected between 1993 and 1995 from 233 Mid-Appalachian streams were used to compare indices of biotic integrity based on genus vs. species level taxonomy. Thirty-seven genera and 197 species of diatoms were identified from these samples. Metrics included in the diatom IBIs included taxa richness, percent relative abundance (PRA) of the dominant diatom taxa, PRA of acidophilic diatoms, PRA of eutrophic diatoms, and PRA of motile diatoms. Diatom richness was positively, though weakly, correlated with indicators of stream eutrophication (total nitrogen, total phosphorus, chloride, total suspended solids) for both the genus and species level metrics. The PRA dominant taxa was significantly related to total P for genus level taxonomy and with total P, turbidity, and pH for the species level metric. The PRA of acidophilic diatoms was significantly correlated with pH, dissolved Al and Mn for both genus and species level metrics. The PRA of eutrophic species was negatively correlated with pH for the genus level metric and with total P and turbidity for the species level metric. Motile diatoms, at both the genus and species level of taxonomy, were significantly correlated with total N, watershed disturbances, and the percent of the watershed in natural vegetation. Overall, genus and species level diatom indices of biotic integrity performed similarly, and for most assessment and monitoring goals, genus level taxonomy may by sufficient.

PRESENTATION	Interregional Comparisons of Sediment Microbial Respiration in Streams	08/15/1999

Hill, B. H., R. K. Hall, P. Husby, A. T. Herlihy, AND M. Dunne. Interregional Comparisons of Sediment Microbial Respiration in Streams. Presented at International Congress on Ecosystem Health: Managing for Ecosystem Health, Sacramento, CA, August 15-20, 1999.
Abstract:	The rate of microbial respiration on fine-grained stream sediments was measured at 369 first to fourth-order streams in the Central Appalachians, Colorado's Southern Rockies, and California's Central Valley in 1994 and 1995. Study streams were randomly selected from the USEPA's Environmental Monitoring and Assessment Program (EMAP). Respiration rate ranged from 0 to 0.621 g 02 g-1 ash free dry mass (AFDM) h-1 in Central Appalachian streams, 0-0.254 g 02g-1 AFDM h-1 in southern Rockies streams, and 0-0.436 g 02 g-1 AFDM h-1 in Central Valley streams. Respiration was significantly lower in Southern Rockies streams and in cold water streams of the Central Appalachians and southern Rockies. Respiration was significantly correlated with stream temperature and chemistry (DOC, total N, total P, K, Cl, and alkalinity), but was not significantly different between years. The uniformity of respiration estimates among the three study regions, and the lack of annual differences suggests that sediment microbial respiration may be collected at any number of scales above the site-level for reliable prediction of respiration patterns at larger spatial scales.

PRESENTATION	Multivariate Analysis of Macroinvertebrate Assemblages to Determine Impacts on Rocky Mountain Stream Ecosystems	05/26/1999

Griffith, M. B., B. H. Hill, A. T. Herlihy, AND P. R. Kaufmann. Multivariate Analysis of Macroinvertebrate Assemblages to Determine Impacts on Rocky Mountain Stream Ecosystems. Presented at North American Benthological Society, Duluth, MN, May 26-29, 1999.
Abstract:	Using reduncancy (RDA) and canonical correlation analysis (CCA) we assessed relationships between chemical and physical characteristics and periphyton at 105 stream sites sampled by REMAP in the mineral belt of the southern Rockies ecoregion in Colorado. We contrasted results obtained with community structure measured by species abundance, genera abundance and community metrics, identifying taxa or metrics diagnostic of stressors in these streams. For species abundance (CCA), 4 axes were significant and accounted for 32% of the species-environment relation. The first axis was correlated with presence of mixed canopy and mid-layer vegetation, % fast water habitat, % coarse substrate, and nonagricultural disturbance and inversely correlated with dissolved organic carbon, embeddedness, width x depth, and % pool habitat. The second axis was correlated with TOC (total organic carbon), P, embeddedness, alkalinity, suspended solids (TSS), and agricultural disturbance and inversely correlated with % coarse substrates, and presence of herbaceous groundcover. For genera abundance (CCA), the axes were not significant. For metrics (RDA), 3 axes were significant and accounted for 95% of the metric-environment relation. The first axis was correlated with P, embeddedness, TOC, and dissolved As and inversely correlated with presence of mixed canopy or mid-layer, % canopy density, % coarse substrate, and % fast water habitat. The second axis was correlated with DOC (dissolved organic carbon), % pool habitat, and alkalinity and inversely correlated with dissolved Cd, Cu, and Zn; TSS; and % fast water habitat. Species abundance is sensitive to the subtle physical effects of mining or agriculture, but this sensitivity is lost with genera abundance. The metrics are more sensitive to chemical effects.

PRESENTATION	Use of Ecological Risk Assessment for Developing and Coordinating Research at Regional and Watershed Scales	05/01/1999

Cormier, S. M., M. SchubauerBerigan, B. Subramanian, S. I. Gordon, M. Smith, AND S. B. Norton. Use of Ecological Risk Assessment for Developing and Coordinating Research at Regional and Watershed Scales. Environmental Effects Monitoring Workshop, Quebec, Canada, October 21, 1998.
Abstract:	A series of studies were undertaken to develop quantitative methods that could be used for ecological risk assessments at a watershed scale. This work contributed to the newly published ecological risk assessment guidelines (USEPA, 1998) and focused attention on the need for a process that helps to organize complex applied ecological research efforts. This paper describes the use of the ecological risk assessment process to provide an organizational framework for conducting and coordinating complex research efforts among federal and state agencies, academia and private industry. Six studies that contributed to the Big Darby Creek Watershed ecological risk assessment are highlighted in this paper. Although an incomplete description of the entire assessment and research effort, the presented studies cover a wide range of topics from the ecological risk assessment process, encompassing watershed scale and regional analysis, relationships among land use and in-stream condition, diagnostic signatures from fish and benthic macroinvertebrate assemblages, and development of regional criteria for chemical exposure. The overall collaborative effort used the ecological risk assessment framework to organize, manage, and communicate a large, interdisciplinary study that involved scientists from federal and state governments, and academia. It provided a framework for describing the value and role of each separate study in a grander scheme and so provided the organizational basis for advancing applied ecological research beyond the individual scientific disciplines especially at regional and watershed scales.

PRESENTATION	Applications of Automated Biomonitoring for Watershed Management	07/18/1999

Morgan, E. L., D. B. Ososanya, D. B. George, J. Frolik, W. T. Waller, J. J. Allen, AND J. M. Lazorchak. Applications of Automated Biomonitoring for Watershed Management. Presented at IUGG Assembly, Birmingham, United Kingdom, July 18-30, 1999.
Abstract:	Over three decades of progress have been made since John Cairns and his associates first coined a new scientific endeavor known as automated biomonitoring. Implementations have ranged from designs for early warning of toxicity in wastewater discharges using fish as sensors, to configurations for automated bioassays using bivalve mollusk or other invertebrates. More recently, remote biosensing devices have been utilized in watershed ecological assessment networks instrumented with water quality monitoring stations and satellite data retrieval. Presently, a new generation of intelligent biosensing systems is being deployed for near, real-time continuous biological monitoring at remote river platforms. One system, built in cooperation with the the University of North Texas, USEPA, and Tennessee Technological University uses digital signal processing and fast Fourier transforms to generate power spectrum densities (PSD) that represent aquatic animal functions, i.e., cardiac and breathing patterns. These PSDs are used as functional features for input into artificial neural networks (ANN). Additionally, values for water hydrograph, chemical/physical characteristics and ecological assessments are used as vectors to the ANN. Once ANN are trained using stressed and non-stressed patterns from biosensors, the system can be used to judge adverse water quality and provide a control sequence capable of triggering an automated water sampler. The control sequence can also alert concerned parties so that samples can be retrieved and processed for causative agents, and corrective action taken when warranted.

PRESENTATION	Quantifying the Regional Effects of Mine Drainage on Stream Ecological Condition in the Colorado Rockies from Probability Survey Data	04/06/1999

Herlihy, A. T., J. M. Lazorchak, F. H. McCormick, D. J. Klemm, M. E. Smith, W. T. Willingham, AND L. P. Parrish. Quantifying the Regional Effects of Mine Drainage on Stream Ecological Condition in the Colorado Rockies from Probability Survey Data. Presented at EMAP Symposium on Western Ecological Systems, San Francisco, CA, April 5-9, 1999.
Abstract:	Runoff from both active and inactive metal mining has contaminated waters and sediments in the Southern Rockies Ecoregion. In 1994 and 1995, as part of its Regional Environmental Monitoring and Assessment Program (REMAP), the USEPA conducted a probability survey of wadeable streams in the mineral belt portion of the Southern Rockies in Colorado. Over the two summers of the study, samples were collected from 73 probability sites (representing 6,630 km of streams) and 13 hand-picked sites for indicators of fish and macroinvertebrate assemblages, physical habitat, and sediment and water chemistry and toxicity. Using stream chemistry, sites were classified into Least Disturbed, Mixed Impacts, and Mine Drainage Impacted Chemical Classes. The study area had roughly equal stream lengths in each of the three classes. Overall, an estimated 1,844 km (28%) of stream length had a sulfate signature of mine drainage, 438 km (7%) exceeded state Zn criteria and 375 km (6%) had water toxic to the test organisms. Sites with elevated metals and toxicity were concentrated in the mine drainage chemical class. Water column toxicity tests (48 hour fathead minnow and Ceriodaphnia survival) were better indicators of mine drainage stress than sediment toxicity test (seven day Hyalella azteca survival). Also, stream macroinvertebrate assemblages were more sensitive to mine drainage stressors than fish assemblages. The synoptic survey data gathered in the REMAP project provides a useful framework and baseline for assessing the extent of mine drainage impacts in the Colorado Rockies.

PRESENTATION	Regional Vulnerability Assessment: Creating a Context for Evaluating Stream Acidification	08/15/1999

Flum, T., B. H. Hill, AND A. T. Herlihy. Regional Vulnerability Assessment: Creating a Context for Evaluating Stream Acidification. Presented at International Congress on Ecosystem Health: Managing for Ecosystem Health, Sacramento, CA, August 15-20, 1999.
Abstract:	USEPA's Regional Vulnerability Assessment (ReVA) program is designed to identify ecosystems that are likely to vary beyond the range of natural variability and thereby experience reduced ecological integrity as a result of natural and human-induced stressors. ReVA makes use of remotely sensed and other data suitable for analysis using GIS to locate particular areas where ecosystems may be exposed to the impact of single and multiple stressors. The immediate focus for ReVA is the mid-Atlantic region where several biological assessments have recently been performed including the USEPA's Environmental Monitoring and Assessment Program (EMAP). EMAP results from the Mid-Atlantic Highland Area (MAHA) expressed as a percentage of total stream miles include: 1) <1% of steams were acidic due to mine drainage; 2) <4% were acidic due to acid deposition; 3) 14% were impacted by mine drainage; 4) 24% had poor riparian habitat quality; and 5) 17% had poor in-stream habitat quality. Applying the EMAP data for the purposes of ReVA requires identifying which of the steam miles with poor riparian habitat and in-stream habitat quality were related to mining activity. This is accomplished by overlaying the EMAP sampling locations on mine sites identified using Thematic Mapper (TM) satellite imagery taken from 1989-1993 as well as mine sites identified in other projects and relating the riparian and in-stream condition to the presence or absence of mines. A framework is then presented that demonstrates how to identify factors potentially interacting with mining including acid deposition, issues related to agricultural land use, and hydrologic alterations. This framework is used to develop a model that accounts for the interactions among the identified factors. The model is then applied to projected locations of future mining activity to serve as a case study for ReVA.

PRESENTATION	Land Use Change Due to Urbanization for the Neuse River Basin	11/14/1999

Matheny, R. W. AND T. Flum. Land Use Change Due to Urbanization for the Neuse River Basin. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	The Urban Growth Model (UGM) was applied to analysis of land use change in the Neuse River Basin as part of a larger project for estimating the regional and broader impact of urbanization. UGM is based on cellular automation (CA) simulation techniques developed at the University of California, Santa Barbara, to predict urban growth. The model uses multiple data sources including topology, road networks, and changes in land use during four different time periods. The rules are more complex than those of a typical CA as the control parameters of the model "self modify" during model runs to best match the pattern of urban growth and other land use changes observed over time. The model was calibrated using land use data from 1950, 1970, 1980, and 1990 at the 1 kilometer scale and best parameters were selected from a suite of model runs made using Monte Carlo methods. Probabilistic predictions were then made using Monte Carlo techniques based on the parameter estimates obtained from the calibration runs and 1992 land use data at 30 meter resolution for 1995, 2000, 2005, 2010, and 2020. Animated dynamic mapping of the simulation results provided as part of the UGM software package were used to visualize the past and predicted future change of urban growth in the Neuse River Basin.

PRESENTATION	A Regional Scale Toxicity Assessment of Sediment in the Mid-Atlantic and Southern Rockies, USA	11/14/1999

Lazorchak, J. M., M. Smith, A. T. Herlihy, AND L. E. Herrin. A Regional Scale Toxicity Assessment of Sediment in the Mid-Atlantic and Southern Rockies, USA. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	As part of the Environmental Monitoring and Assessment Program (EMAP), sediment samples were collected to assess toxicity on a regional scale in streams and rivers in the Mid-Atlantic U.S. in 1994, 1997 and 1998, and in the Colorado Rocky Mountains in 1994 and 1995. Sample sites were selected randomly using a probability design so that the results could be inferred for the entire region. Sediments were collected from each site by scooping 11 small samples of surficial sediments within a 150-800 m long sample reach (reach length was proportional to stream width) and composited in a bucket. Samples were then placed in a plastic bag and shipped on ice to Cincinnati and stored at 4-6oC. A 7-day Hyalella azteca (amphipod) lethality and growth method was used to assess the toxicity of all sedment samples. During the spring of 1994 in Mid-Atlantic streams, an estimated 10,700 km of stream length (5.7% of the 188,700 km in the target population) were found to have toxic sediment (survival or growth significantly less than the control). During the summers of 1997 and 1998 in Mid-Atlantic streams and river sediments, an estimated 21,830 km (8.7%) of the 250,500 km of target length were found to be toxic. In the Southern Colorado Rockies, an estimated 422 km (6.4%) of the 6,600 km of target stream length had toxic sediments. These results demonstrate the utility of synoptic probability based surveys to assess regional extent of sediment toxicity/contamination.

PRESENTATION	Metallothionein Gene Transcription as An Indicator of Metal Exposure in Fathead Minnows	11/13/1999

Reddy, T. V., D. L. Lattier, J. M. Lazorchak, G. P. Toth, AND M. E. Smith. Metallothionein Gene Transcription as An Indicator of Metal Exposure in Fathead Minnows. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	Metallothionein is a cysteine rich, low molecular weight, metal binding protein. Basal levels of endogenous metallothioneins (MT) have been reported in all eucaryotes. MT has been shown to play an essential role in regulating physiological requirements of essential metals such as zinc and copper, and elimination of non-essential metals such as cadmium and lead from the system. Our objectives are to investigate metallothionein gene (Mt) expression in aquatic organisms, and use the onset of Mt gene transcription as an indicator of metal exposure. To achieve our objectives, we designed Mt-specific synthetic oligonucleotides based on the published gene sequence for common carp (Cyprinus carpio). Induction of Mt gene expression was measured in newly hatched fathead minnow larvae (Pimephales promelas) exposed to varied concentrations of zinc sulfate. Fathead minnow larvae were exposed for 48 hours to zinc concentations between 25 and 250 ug/L. Following exposure, total RNA was isolated from larvae and Mt gene transcription was analyzed by RT-PCR. Results suggest that fathead minnows express constitutive levels of Mt messenger RNA; however, the gene was inducible with zinc in a dose dependent manner. The lowest concentration at which Mt was induced (25-50 ug/L zinc) was less than that which produced effects measured in standard USEPA 7-day fathead minnow short-term chronic survival (LC50 > 240 ug/L), and growth (IC25 > 90 ug/L) tests. Mt gene transcription was induced at concentrations far below those that result in the onset of sublethal toxicity. The observed sensitivity of Mt gene expression renders this approach a sound aquatic, field-based indicator of heavy metal exposures.

PRESENTATION	Development of Dna Based Microsatellite Marker Technology for Studies of Genetic Diversity in Central Stoneroller (Campostoma Anomalum) Populations	11/13/1999

Dimsoski, P. AND G. P. Toth. Development of Dna Based Microsatellite Marker Technology for Studies of Genetic Diversity in Central Stoneroller (Campostoma Anomalum) Populations. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	The level of genetic diversity of aquatic species is a critical indicator of stream system condition for which few data exist. There is strong evidence suggesting that environmental stressors affect the genetic diversity of exposed populations. In order to study genetic diversity, we have developed a set of DNA microsatellite markers. The markers are dinucleotide (CA) repeats which are assumed to be randomly distributed across the genome of Campostoma anomalum (Central Stoneroller). A high level of polymorphism, which is essential for genetic diversity and monitoring studies of populations, is generated by the variable number of nucleotide repeats. A microsatellite-enriched genomic library was constructed, followed by isolation of CA-repeat DNA sequences that were cloned into E. coli. Over 50% of the colonies were 'positive' for microsatellite inserts. The unique flanking regions and dinucleotide repeats of insert-containing colonies were sequenced from both ends of the insert. All of the inserts previously identified as 'positives' contained CA-repeats. The number of repeat units on the 22 sequenced microsatellites ranged from 10 to over 100. It is expected that a higher level of polymorphism will be associated with the higher number of dinucleotide repeats. A set of unique microsatellite primers was designed and prepared for automated genotyping and sequencing. Ten of the 22 designed primers yielded PCR products of the expected size. The markers will be used to characterize the level of heterozygosity for Central Stonerollers across a range of stressor exposures in regional studies of stream ecosystem condition in the Eastern Untied States.

PRESENTATION	A New Approach for the Culture of Fathead Minnows, Pimephales Promelas	11/13/1999

Lazorchak, J. M., M. E. Smith, L. E. Herrin, AND T. A. Hughes. A New Approach for the Culture of Fathead Minnows, Pimephales Promelas. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	Fathead minnows (Pimphales promelas) are routinely cultured for use in aquatic toxicology studies. Most culture systems consist of a series of 4 to 30 individual tanks with 16 - 18 fish (2 males and 14-16 females) in each tank. The new mass culture system consists of six 50 gallon tanks, each tank containing 76 fish (16 males and 60 females). From April 1997 to March 1998, the new mass system produced an average of 3800 eggs per day. The one year average for the previous individual tank system was 2900 eggs per day. Operation and maintenance was reduced, since only six large tanks need to be cleaned on a routine basis, as opposed to 22 glass tanks. Stainless steel tanks eliminated tank breakage and the daily water usage was reduced by 45%. This system required one-half the floor space necessary for the equivalent system using 20 gallon tanks. Analysis of reference toxicant data from fish cultured using both systems indicates no change in the sensitivity of the test animals. The potassium chloride mean acute LC50 for fish from the individual tank culture system was 800 mg/l, with a C.V. of 21.1%. The potassium chloride mean acute LC50 for the fish from the new mass culture system was 808 mg/l, with a C.V. of 11.8%. There was no change in the mean LC50 values for fish cultured using both systems, but the C.V. was reduced by 45% for the fish in the new culture system. A description of the mass culture system and the water treatment system will be provided.

PRESENTATION	A New Approach for Culturing Lemna Minor (Duckweed) and Standardized Method for Using Atrazine as a Reference Toxicant	11/13/1999

Lazorchak, J. M., E. M. SuszcynskyMeister, T. A. Hughes, M. E. Smith, AND T. V. Reddy. A New Approach for Culturing Lemna Minor (Duckweed) and Standardized Method for Using Atrazine as a Reference Toxicant. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	Lemna minor (Duckweed) is commonly used in aquatic toxicity investigations. Methods for culturing and testing with reference toxicants, such as atrazine, are somewhat variable among researchers. Our goal was to develop standardized methods of culturing and testing for use with L. minor. A two-step culturing system was developed to readily provide healthy L. minor plants with minimal algal growth for toxicity testing. The first step consisted of a flow-through mass holding culture with nutrients supplied from commercial fertilizer stakes. The second step involved taking two frond plants from the flow-through culture to start a smaller static renewal culture that used a modified algal nutrient medium. Plants from both the mass and static cultures were monitored monthly for chlorophyll a levels. Monthly chlorophyll a levels in mass cultures averaged 0.85 mg/g wet tissue weight. Static cultures averaged 1.0 mg/g wet tissue weight. Total frond production was monitored bi-weekly in the static cultures with frond doubling occurring every three to four days. Atrazine was developed as a new reference toxicant for use in evaluating the consistency of the culture method. A 0 .5 dilution series was used with a 100% dilution concentration of 500 ug/L atrazine. Preliminary results indicate a frond number NOEC of 25-50 ug/L. The percent frond increase IC25 range was 35-60 ug/L and IC50 range was 95-170 ug/L. Wet weight measurements resulted in an NOEC of 25-50 ug/L and an IC25 range of 45-70 ug/L.

PRESENTATION	Development of a Stream Benthos Integrity Index (Sbii) for the Mid-Atlantic Highlands Region	11/14/1999

Klemm, D. J., F. A. Fulk, W. T. Thoeny, AND K. A. Blocksom. Development of a Stream Benthos Integrity Index (Sbii) for the Mid-Atlantic Highlands Region. Presented at Society of Environmental Toxicology and Chemistry, Philadelphia, PA, November 12-14, 1999.
Abstract:	A multimetric index using benthic macroinvertebrates was developed to evaluate the biological condition of wadeable streams in the MAHA region. Ecological concepts and biodiversity of macroinvertebrates were used to develop the SBII, and then a statistical approach was used to validate the index. Benthic macroinvertebrate samples were collected from 647 sites in the MAHA region during 1993-1995 as part of the USEPA's Environmental Monitoring and Assessment Program (EMAP). Macroinvertebrates were collected from riffle/run and pool/glide habitats of wadeable steams and identified to the lowest possible taxon in the laboratory. An initial SBII was developed using ten population and community metrics (number of taxa, HBI, number of individuals/taxon, % intolerant taxa, % non-insects, % chironomids, % individual dominant taxon, % EPT taxa, EPT index, and % oligochaetes/leeches). To assess the statistical robustness of the initial SBII, forty-seven candidate macroinvertebrate metrics were evaluated statistically using univariate and multivariate analyses: 1) to reduce the large number of candidate metrics into a set that captures the information of the benthic macroinvertebrate data, and 2) to ascertain the ability of the selected metrics to discriminate among effects caused by different classes of stressors, such as habitat degradation and pollutant concentrations. The initial SBII was found to be highly correlated with the first principal component of the reduced set of candidate metrics indicating that most of the metrics were well justified statistically. The final SBII consisted of metrics that met statistical criteria and/or best professional judgement.

PRESENTATION	Evaluating Soil Erosion Parameter Estimates from Different Data Sources	09/22/1999

Senay, G., S. M. Cormier, AND B. Subramanian. Evaluating Soil Erosion Parameter Estimates from Different Data Sources. Presented at National Conference on Environmental Problem Solving With Geographic Information Systems, Cincinnati, OH, September 22-24, 1999.
Abstract:	Topographic factors and soil loss estimates that were derived from thee data sources (STATSGO, 30-m DEM, and 3-arc second DEM) were compared. Slope magnitudes derived from the three data sources were consistently different. Slopes from the DEMs tended to provide a flattened surface with large areas having 0.0% values. The 3-arc second DEM generally produced a lower slope estimate than either the STATSGO or 30-m DEM. Slopes from the 30-m DEM fell between the 3-arc second and the STATSGO. Thus, the STATSGO database provided a higher slope estimate than either of the two DEM sources. However, slopes from the 30-m DEM and the STATSGO were more comparable than the slope estimates from 30-m and 3-arc second DEMs. For example, 0.0, 10.0, and 20.0% slope classes from the 30-m DEM showed mean values of 0.0, 4.0, and 6.0%, respectively with the 3-arc second DEM, and 4.0, 18.0, and 24.0% respectively with the STATSGO. Along with the slope differences, potential erosion estimate trends varied between the data sets although the soil loss differences were higher than the slope differences. A recommendation was made to validate slope and erosion estimates using field data; however, it appeared that STATSGO may be more reliable than the two data sets for smaller slopes and either STATSGO or the 30-m DEM may be used for higher slopes. Due to the ease of GIS in combining data from various sources, the importance of a thorough understanding of data accuracy standards and their limitations and intended use were highlighted.

PRESENTATION	Assessing the Impact of Landuse/Landcover on Stream Chemistry in Maryland	09/22/1999

Senay, G., S. M. Cormier, B. Subramanian, AND J. SchubauerBerigan. Assessing the Impact of Landuse/Landcover on Stream Chemistry in Maryland. Presented at National Conference on Environmental Problem Solving with Geographic Information Systems, Cincinnati, OH, September 22-24, 1999.
Abstract:	Spatial and statistical analyses were conducted to investigate the relationships between stream chemistry (nitrate, sulfate, dissolved organic carbon, etc.), habitat and satellite-derived landuse maps for the state of Maryland. Hydrologic Unit Code (HUC) watershed boundaries (8-digit) were used as the basis for grouping stream chemistry data. Percent land cover area (forestland, cropland, pastureland, etc.) within an HUC was computed in a Geographic Information Systems (GIS) environment in Arc/Info. It was shown that percent agricultural lands (crop, pasture, etc.) were positively correlated (significant) with nitrate and dissolved organic carbon (DOC), while percent forest cover was negatively correlated (significant) with nitrate and DOC. The results were in agreement with the reports of other researchers and with the fundamental understanding of the role of the land cover types in chemical loadings to the streams. Generally, percent forest and percent agriculture displayed opposite signs in the correlation matrix with stream chemistry data, including sulfate and pH variables. Although there was a negative correlation between percent forest and nitrate in the streams, this was likely due to a reduction in the area occupied by agricultural lands (source of nitrate), not the amount of forest area per se. This was supported by the presence of a negative correlation between percent forest area and percent agricultural area. These data indicated that agriculture was the main source of nitrate pollution in Maryland streams. Further study is needed to investigate the nitrogen retaining capacity of stream-buffer types and identify best management practices that reduce loss of valuable nutrients from farm soils and their deleterious export to streams and estuaries.

PRESENTATION	Home Ranges and Habitat Use of Suburban Red-Shouldered Hawks	08/01/1999

Dykstra, C. R., J. L. Hays, F. B. Daniel, AND M. M. Simon. Home Ranges and Habitat Use of Suburban Red-Shouldered Hawks. Presented at American Ornithologist Union, Ithaca, NY, August 1, 1999.
Abstract:	Radio telemetry was used to determine home range size and habitat use for breeding season and non-breedng season red-shouldered hawks nesting in a surburban area in southwestern Ohio. Home ranges averaged 96.0 ha for males (n=4) and 48.3 for females (n-2) during the breeding season, and 182.8 ha during the non-breeding season (n=3 males and 2 females). During the breeding season, the home ranges comprised 60.6% forest, 22.9% lawns/fields, 15.6% urban, and 0.4% water/wetland, on average. Each home range contained an average of 119 buildings (primarily residences), a density of 1.5 buildings/ha. Habitats where radio-tagged birds were observed perching were classified by researchers. During the breeding season, 51% of the observations of hawks were in upland forests/brush, 26% in lawns/fields, 1% in hosing/urban areas, nd 21% along the edges of streams or ponds (n=164 observations, distribution differs from distribution of habitat in home ranges, chi-square p <0.001). For the non-breeding season, home ranges were larger and comprised 58.1% forest, 22.2% lawns/fields, 18.8% urban, and 0.3% water/wetland, on average. Non-breeding home ranges contained an average of 311 buildings, a density of 1.6 buildings/ha. During the non-breeding season, 48% of the observations of hawks were in upland forests/brush, 41% in lawns/fields, 0% in housing/urban areas, and 11% along the edges of streams or ponds (n=126 observations, chi-square p<0.001).

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