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Climate change poses unique challenges for protecting environmental resources upon which our society depends. Adapting to changing climate hinges on knowing the regional and local vulnerabilities and impacts to water resources and ecosystem services. Determining social and ecolo...

Population growth, urban expansion, and the warming climate have and will continue to stress our coastal ecosystems. Decisions on how and when to respond with stewardship, adaptation, and mitigation are made by individuals, municipalities, states, and agencies. These decisions ...

Assessments of the long-term impacts of global changes in climate, ultraviolet (UV) radiation and land use on ecosystems require scientific data, concepts and models that describe the responses of ecosystem health to stresses related to the changes as well as information and mode...

This research is funded through an interagency agreement with NASA. The research in this project is contributing to assessments of the effects of land use in central Brazil on: 1) the stocks and cycling rates of carbon and nutrient cycling; 2) the function and structure of soil ...

To effectively manage watersheds, the assessment of watershed ecological response to physicochemical stressors such as nutrients, sediments, pathogens, and toxics over broad spatial and temporal scales is needed. Assessments at this level of complexity requires the development of...

<p>Urbanization has profound impacts on the hydrology and ecology of streams via alteration in water temperatures, peak and base flows, and nutrient, sediment, and contaminant inputs. Storm water management (SWM) is commonly used to reduce these impacts; however, comprehensive w...

Conceptual models predict that unpolluted, aggrading forest ecosystems tightly retain available nitrogen (N) until declining productivity by mature trees and storage in detritus reduces the demand for essential nutrients, and N export increases to equal input. Short-term nitrate ...

Elevated nitrate levels in streams and groundwater pose human and ecological threats. Minebank Run, an urban stream in Baltimore MD, will be restored in 2004/2005 using various techniques including reshaping stream banks to reconnect stream channel to flood plain, stream bank r...

The objective of the Office of Research and Development (ORD) ecosystem restoration research strategy is to evaluate the effectiveness of restoration and management practices for achieving desired environmental conditions that protect and enhance ecosystem services for society. T...

Over the past decade, our group has been working to bring coastal ecosystems into integrated basin-lakewide monitoring and assessment strategies for the Great Lakes. We have conducted a wide range of research on coastal tributaries, coastal wetlands, semi-enclosed embayments an...

Case studies are a useful vehicle for developing and testing conceptual models, classification systems, diagnostic tools and models, and stressor-response relationships. Furthermore, case studies focused on specific places or issues of interest to the Agency provide an excellent ...

The objective of the proposed study is to assess the responsiveness of indicators of ecosystem function to three intensities of watershed disturbance in four regions. An integrated assessment of abiotic and biotic condition of streams will be conducted to assess streams affected...

The ERD has a long history in providing model research and development and technical support to Regions, States and the Office of Water for watersheds/water quality ecosystem research. The ERD efforts are described in major subtasks comprising the Program. Briefly, these are:<b...

Mercury is released from a variety of sources and exhibits a complicated chemistry. The primary exposure pathway for humans and wildlife is the consumption of contaminated fish. The goal of this research is to provide the scientific information needed for EPA to assess and manag...

<p>There is increasing evidence that stream metabolic processes that increase CO2 flux to the atmosphere will be highly sensitive to rising temperatures, changing precipitation patterns and shifts in carbon loading from watersheds. In addition, preliminary data suggest that th...

Terrestrial ecosystems are major sources of N pollution to aquatic ecosystems. Predicting N export to streams is a critical goal of non-point source modeling. This study was conducted to assess the effect of terrestrial N cycling on stream N export using long-term monitoring da...

A habitat-change model was used to compare past, present, and future land cover and management practices to assess potential impacts of alternative agricultural practices on wildlife in two agricultural watersheds, Walnut Creek and Buck Creek, in central Iowa, USA. This approach ...

There is a growing need for cost effective ways to assess conditions of and risks to ecological resources at a variety of scales over broad regions. Indicators, models and assessment tools are needed to evaluate water bodies at risk to non-point source pollution and to be able t...

The U.S. Environmental Protection Agency, in partnership with others, is embarking on the new Healthy Watersheds Initiative to protect our remaining healthy watersheds, prevent them from becoming impaired, and accelerate our restoration successes. In November 2010, a Healthy Wate...

Biological invasions are one of the foremost threats to the integrity of aquatic ecosystems in the U.S., but little is known regarding the invasion dynamics of non-indigenous fishes in streams. Southeastern streams, renowned for their exceptional levels of fish endemism and dive...

We are measuring the dissolved nitrous oxide concentration in 17 headwater streams in the South Fork Broad River, Georgia watershed on a monthly basis. The selected small streams drain watersheds dominated by forest, pasture, developed, or mixed land uses. Nitrous oxide concentr...

Yields and retention of inorganic nitrogen (DIN) and nitrate concentrations in surface runoff are summarized for 28 high elevation watersheds in the Sierra Nevada, California and Rocky Mountains of Wyoming and Colorado. Catchments ranged in elevation from 2475 to 3603 m and from...

We have been sampling nutrient concentrations in 17 headwater streams within the South Fork Broad River (SFBR) watershed on a monthly basis since November 2001. The streams were classified as either developed (n=4), agriculture/pasture (n=4), mixed land use (n=6) or forested (n=3...

Poster for the EPA Science Forum.<br><br>This collaborative research effort assessed how changing coastal plain watershed land-uses influence the delivery of nutrients and sediments to estuaries and subsequently how estauries respond to increasing loads of pollutants. <br><br>

Seventeen headwater watersheds within the SFBR watershed ranging from 0.5 to 3.4 km2 were selected. We have been monitoring concentrations of the trace gases nitrous oxide, methane, and carbon dioxide, and other parameters (T, conductivity, dissolved oxygen, pH, nutrients, flow r...