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Showing 1 to 20 of 56 for “"bioassessment"”.
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Applying the Reference Condition Approach to bioassessment of Cape Breton Island streams
The reference condition approach (RCA) to bioassessment assesses the effect of human activity on ecosystems relative to sites that are relatively unexposed to such activity. This study uses the RCA to characterize the nature of relatively pristine streams on Cape Breton Island, Nova Scotia as a …
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A macroinvertebrate bioassessment of two streams on Turnbull National Wildlife Refuge (TNWR)
<p>This project focused on highly impacted streams at Turnbull National Wildlife Refuge, Cheney, WA to evaluate the health status and ecosystem integrity of the water bodies. Turnbull National Wildlife Refuge contains over 3,000 acres of wetlands, and provides high quality habitat for migrating and …
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The Effect of Sample Size on Rapid Bioassessment Scores and Management Efficiency
<p>The rapid bioassessment method for stream bio monitoring generally uses a fixed count of 200 macro invertebrates as the standard subsample size. This number has been argued to be too small to provide accurate estimates on the richness of macro invertebrate communities and is believed to give …
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Using GIS and Land Use Data to Select Candidate Reference Sites for Stream Bioassessment
… reference condition by sub-ecoregion for a rapid bioassessment of streams statewide. Instead of relying on best professional judgment or previous knowledge of a limited number of sites, we performed an objective evaluation of cumulative impact on all catchments using land use data sets. These …
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Integrative Bioassessment of Acid Mine Drainage Impacts on the Upper Powell River Watershed, Southwestern Virginia
… Powell River watershed. Emphasis was placed upon bioassessment methodologies and AMD impacts beyond the zone of pH depression. Major findings and processes developed included: 1) an Ecotoxicological Rating (ETR) system was developed that integrates chemical, toxicological, and ecological data into …
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A Cost Effective Approach to Taxonomic Resolution For Bioassessment and Monitoring Programs in the State of Georgia
… for streams in Georgia according to the Rapid Bioassessment Protocols For Wadeable Streams and Rivers. Streams will ultimately be classified into categories of impairment so that management decisions can be made in accordance with the Clean Water Act. A cost-effective approach to accomplish …
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Studies of Benthic Macroinvertebrates in Western Virginia Streams as Related to the Implementation of Rapid Bioassessment Techniques
… sampling approach, commonly used in rapid bioassessments, in assessing the biological condition of lotic systems. I compared a typical standardized qualitative sampling method with subsampling with a typical quantitative sampling method on a stream with varying degrees of impairment. …
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Bioassessment and the Partitioning of Community Composition and Diversity Across Spatial Scales in Wetlands of the Bonneville Basin
… objectives of this project were to 1) Develop bioassessment procedures for artesian wetlands of the Bonneville Basin using macroinvertebrates and 2) Determine patterns of community composition and diversity for macroinvertebrates and metaphyton algae at multiple scales in Bonneville Basin …
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An evaluation of SASS (South African scoring system) as a tool for the rapid bioassessment of water quality
… South African Scoring System (SASS) is a rapid bioassessment technique based on one component of riverine biotas, the benthic macroinvertebrates. Each taxon is assigned a tolerance/sensitivity score, which are summed to provide a Total Score. The Average Score per Taxon (ASPT) is calculated by …
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Effects of stream network topology on fish assemblage structure and bioassessment sensitivity in the mid-Atlantic highlands, USA
… environmental quality assessments (i.e., bioassessments). In chapter 1, I evaluated the effects of stream networks by comparing fish assemblages between sites with and without large downstream confluences (>3rd order) in western Virginia, USA (i.e., mainstem tributaries and headwater …
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Analyses of Two Aspects of Study Design for Bioassessment With Benthic Macroinvertebrates: Single Versus Multiple Habitat Sampling and Taxonomic Identification Level
Bioassessment is the concept of evaluating the ecological condition of habitats by surveying the resident assemblages of living organisms. Conducting bioassessment with benthic macroinvertebrates is still evolving and continues to be refined. There are strongly divided opinions about study design, …
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Stratification of Southern Georgia Streams For Rapid Bioassessment Focusing on Differences in Structure and Function of Black Water and Clear Water Streams
<p>As part of a rapid bioassessment project for the state of Georgia, relatively unimpaired reference streams and impaired sites were sampled for biological, chemical and physical parameters, and macroinvertebrates were identified. The metrics, biological, physical and chemical metrics, were …
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Biological assessment of tropical riverine systems using aquatic macroinvertebrates in Tanzania, East Africa
In Tanzania, and in East Africa in general, bioassessment methods for monitoring and assessing riverine ecosystems are not yet in place. This thesis describes the development of a macroinvertebrate-based bioassessment method for assessing the degree of anthropogenic disturbance in Tanzanian rivers. …
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Development and Implementation of Integrative Bioassessment Techniques to Delineate Small Order Acid Mine Drainage Impacted Streams of the North Fork Powell River, Southwestern Virginia
Acid mine drainage (AMD) results from the oxidation of pyretic mineralogy, exposed by mining operations to oxygen and water. This reaction produces sulfuric acid and liberates heavy metals from the surrounding mineralogy and impairs water quality and freshwater communities. The U.S. Army Corps of …
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A Method Comparison and Stressor-Response Experimental Study of Nitrogen and Phosphorus Impacts to Periphyton in Ozark Streams
<p>Stream bioassessment is important for understanding algal-nutrient relationships and the development of scientifically defensible numeric nutrient criteria. However, multiple methods of periphyton data collection are currently used, and little is known about the comparability of resulting …
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Ecologically-focused calibration of hydrological models for environmental flow applications
… possible, gaged flow data are used; however, bioassessment sites are frequently ungaged and hydrological models must be used to characterize flow alteration. Physically-based rainfall-runoff models typically utilize a "best overall fit" calibration criterion, such as the Nash-Sutcliffe …
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Spatial and temporal heterogeneity in lotic systems : implications for defining reference conditions for macroinvertebrates
… the South African Scoring System (SASS), a rapid bioassessment method. The implication of spatial variability at regional, subregional and habitat levels, and temporal variability for defining reference conditions for macroinvertebrates was evaluated.
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The Effects of Nutrient Concentrations on Macroinvertebrate Distributions in Georgia
… September to February), using the EPA's rapid bioassessment protocol (RBP). The concentrations of nutrients were measured in mg/L and ranged as follows: nitrite and nitrite/nitrate < 0.01 to >1.0, ammonia < 0.03 to 3.0, and phosphorous < 0.01 to 1.2. Analysis determined (1) the RBP has the …
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Effects of Cattle Exclusion on Stream Habitat in the Shenandoah Valley, Virginia
… in Rockingham County, VA were used to calculate bioassessment metrics. Fourteen sites made up 4 longitudinal studies where improvement of biotic condition with distance from cattle impact was examined. Linear regression and multilevel modeling results indicated improving macroinvertebrate …
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