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Water Quality
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Water quality work at the Division is being conducted under the
aquatic stressors research topic area - The ultimate goal of this research is to develop scientifically valid approaches to protect and restore the ecological integrity of aquatic ecosystems from the impacts of multiple aquatic stressors. The immediate focus is to develop and improve assessment methodologies, diagnostic capabilities, and ecological criteria to guide management options for 1) protection and restoration, and 2) remediation efforts to meet designated uses. The context for this research is the common management goal of protecting aquatic systems to prevent degradation of habitat, loss of ecosystem function, and reduced biodiversity. To this end, environmental managers must be able to: 1) assess the condition of an aquatic resource and determine the degree of impairment, 2) diagnose the causes of impairment, 3) forecast the effects of changes in stressor levels, and 4) develop and implement remediation and maintenance strategies. Meeting the goals of effective management and protection of aquatic resources requires that multiple research elements be in place to provide the needed tools. This research provides a means to develop these tools. Research centers on the effects of aquatic stressors, including habitat alteration, nutrients, and toxic chemicals. This approach is consistent with recent scientific consensus, recognizing that these stressors have the greatest potential for causing adverse effects to aquatic ecosystems. An important element of this research program is the development of diagnostic tools for a decision support system for resource managers.
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| Water Quality Long Term Goal: Provide the approaches and methods to develop and apply criteria for habitat alteration, nutrients, and toxic chemicals that will support designated uses for aquatic ecosystems. | |
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Habitat alteration research focuses on quantifying the life support functions of specific habitat and habitat complexes to predict the biological effects of habitat alteration and/or loss on populations of valued aquatic species and communities. The main goal of this research is to quantify the role of habitat in maintaining healthy aquatic and aquatic-dependent populations by: 1) describing the relationships between habitat and biota at the appropriate scales to quantify effects on population and community endpoints due to habitat alteration, 2) synthesizing the cumulative support function of individual habitats and aquatic ecosystems, and 3) integrating habitat alteration effects with effects from other stressors. Necessary elements of this research include providing: suites of species endpoints, assessment and measurement endpoints and strategies, habitat alteration-population response relationships, classification schemes, and models for extrapolating data across spacial scales. Habitat-related research in the Division centers on increasing our understanding of habitat complexity and variability within freshwater coastal ecosystems, establishing the structuring role of hydrogeomorphology in determining habitat mosaics and wetland classifications, and linking wetland and stream biota to habitat characteristics at a variety of spatial scales. Work under this area is being done in connection with NHEERL's Science to Achieve Results (STAR) program to develop Great Lakes environmental indicators (glei.nrri.umn.edu/default). Abstracts of Habitat Alteration Ongoing Research Projects
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Understanding the responses of receiving waters to excess nutrients is the focus of this portion of the Division's research program. The main goal is to define and quantify relationships between nutrient loading and ecological responses for different aquatic resource types to develop the basis for deriving numeric nutrient criteria. Principal components of this research include providing conceptual models for specific assessment endpoints, a state of the science evaluation to develop and improve nutrient-load responses, classification schemes, standard measurement endpoints, and nutrient load-response models. The most important response categories for study include:
These endpoints are markers to indicate a substantial risk to biological populations and /or a fundamental change in the nature of shallow coastal ecosystems and are, therefore, prime response measures to serve in creating criteria and establishing Total Maximum Daily Loads (TMDLS). The associate objective is to develop nutrient-response relationships in the context of a classification scheme for each of these endpoints so that aquatic systems can be grouped according to their expected sensitivity to the effects of nutrient loading. Classification efforts focus on understanding and linking the influence of physical, chemical, and biological factors on response to nutrients across the nation's coastal receiving waters. For the Division, as a partner with its sister Divisions, this work provides a natural extension of efforts in the Great Lakes coastal wetlands over the past few years. The main objectives of this research are to: develop sampling methodologies for nutrient characterization within systems; define factors influencing loading and response; evaluate suitable measures for biological response and vulnerability; perform assessments, including stable isotope analyses and in situ experimental assays; and develop a framework for hydrogeomorphic classification relevant to nutrient loading responses. Work under this area is being done in connection with NHEERL's Science to Achieve Results (STAR) program to develop Great Lakes environmental indicators (glei.nrri.umn.edu/default). |
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Toxic chemicals research focuses on developing methods to reduce uncertainty and significantly advance current methods to derive criteria for toxic chemicals. The general goal of this research is to develop scientifically-defensible methods for characterizing the risks of toxic chemicals to aquatic and aquatic-dependent populations and communities. The key elements for improving aquatic risk assessments and criteria for toxic chemicals include providing methods to: improve criteria at the individual level based on improved characterization of risks, link individual-level data to population endpoints, support risk assessments for chemicals with limited data, and evaluate risks on populations at various spatial scales in the context of other stressors. Research projects under this plan center around conceptual models that will support the development and demonstration of frameworks for better assessing the risks of both non-bioaccumulative and bioaccumulative chemicals. Abstracts of Toxic Chemical Ongoing Research Projects
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| Water Quality Long Term Goal: Provide the tools to assess and diagnose sources and causes of impairment in aquatic systems. | |
Diagnostics research provides an approach for identifying the causes of biological impairment and linking watersheds with receiving water bodies to support the TMDL process and other regulatory programs. The primary goals of this research are to provide: a framework for interpreting cause and effect relationships, single-stressor diagnostic methods and models to determine the primary source of biological impairment of aquatic ecosystems, and methods and models to allocate and forecast causality among multiple stressors for use in restoration and remediation actions. The principal components of this research area will provide: the scientific foundation and information management scheme for listing impaired sites under Section 303d of the Clean Water Act (CWA), and a classification framework for surface waters, watersheds, and regions; diagnostic methods to distinguish among major classes of single and multiple aquatic stressors; and diagnostic tools for forecasting approaches. Specific projects are being conducted to establish the conceptual framework to guide implementation of diagnostics, provide case studies to develop and test methods for both single and multiple stressors, and to establish the structure for a decision support system. Abstracts of Diagnostics Ongoing Research Projects |
