CEAP study examines nitrogen, copper levels in Bay watershed

Aug 20, 2010

A comprehensive study of pollutants in a major Chesapeake Bay tributary revealed troublesome levels of nitrogen and copper that could flow into the Bay, according to U.S. Department of Agriculture (USDA) scientists and their cooperators.

Scientists with USDA's Agricultural Research Service (ARS) and their collaborators conducted the study as part of the Conservation Effects Assessment Project (CEAP) for Maryland's Choptank River Watershed, which flows into the . CEAP began in 2004 and focuses on the effects of conservation practices and Farm Bill conservation programs on 37 watersheds nationwide.

Greg McCarty, a soil scientist with the ARS Hydrology and Remote Sensing Laboratory at Beltsville, Md., and Laura McConnell, a chemist at the ARS Environmental Management and Byproducts Utilization Laboratory in Beltsville, lead the team's CEAP Choptank project. ARS is USDA's principal intramural scientific research agency.

Monitoring the Choptank provides information needed to develop new conservation practices, refine existing ones, and design programs to evaluate efforts to clean the endangered Bay.

Sampling the water every two months for three years, the scientists found that nitrate concentrations often exceeded levels that can cause . Nitrate concentrations were highest at the headwaters where farming is concentrated, suggesting that agricultural fertilizers, including manure and poultry litter, are primary sources.

But phosphorus concentrations were similar throughout the river, suggesting multiple sources. While some evidence points to wastewater treatment plants as a likely primary source, agriculture is also a major contributor.

High copper concentrations were found in almost all samples at the lower reaches of the Choptank, but not in the upstream areas. This suggests that agriculture is not the primary source. The levels were high enough to be toxic to clams and other aquatic invertebrates that help feed and filter the Bay.

Herbicides and their byproducts were present year-round. Concentrations did not approach established levels of concern for aquatic organisms. Still, this research shows the importance of agricultural practices that reduce herbicide losses, particularly from springtime applications.

The results of this study were published in the journal Science of the Total Environment.

Explore further: Gimmicks and technology: California learns to save water

More information: Read more about this research in the August 2010 issue of Agricultural Research magazine, available online at: www.ars.usda.gov/is/AR/archive/aug10/chesapeake0810.htm

Related Stories

Water Quality Model Passes Another Test

Feb 25, 2010

(PhysOrg.com) -- A test of the SWAT (Soil and Water Assessment Tool) model on a small watershed with poor water quality in Maryland showed that the model accurately estimated pollutant levels over the long ...

Is your drinking water safe?

Feb 28, 2008

Lake Bloomington is a major source of drinking water for residents of Bloomington, IL, and has a history of nitrate concentrations that exceed safe levels. Because Lake Bloomington has a record of elevated nitrate levels, ...

Recommended for you

Gimmicks and technology: California learns to save water

23 hours ago

Billboards and TV commercials, living room visits, guess-your-water-use booths, and awards for water stinginess—a wealthy swath of Orange County that once had one of the worst records for water conservation ...

Cities, regions call for 'robust' world climate pact

Jul 03, 2015

Thousands of cities, provinces and states from around the world urged national governments on Thursday to deliver a "robust, binding, equitable and universal" planet-saving climate pact in December.

Will climate change put mussels off the menu?

Jul 03, 2015

Climate change models predict that sea temperatures will rise significantly, including in the tropics. In these areas, rainfall is also predicted to increase, reducing the salt concentration of the surface ...

As nations dither, cities pick up climate slack

Jul 02, 2015

Their national governments hamstrung by domestic politics, stretched budgets and diplomatic inertia, many cities and provinces have taken a leading role—driven by necessity—in efforts to arrest galloping ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.