CEAP study examines nitrogen, copper levels in Bay watershed

August 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 Chesapeake Bay. 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 algal blooms. 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.
-end-
Read more about this research in the August 2010 issue of Agricultural Research magazine, available online at: http://www.ars.usda.gov/is/AR/archive/aug10/chesapeake0810.htm.

See the ARS Electronic Information Kit on the Chesapeake Bay. http://www.ars.usda.gov/is/br/bay/index.htm

USDA is an equal opportunity provider, employer and lender. To file a complaint of discrimination, write: USDA, Director, Office of Civil Rights, 1400 Independence Ave., S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice), or (202) 720-6382 (TDD).

United States Department of Agriculture - Research, Education and Economics

Related Nitrogen Articles from Brightsurf:

Chemistry: How nitrogen is transferred by a catalyst
Catalysts with a metal-nitrogen bond can transfer nitrogen to organic molecules.

Illinois research links soil nitrogen levels to corn yield and nitrogen losses
What exactly is the relationship between soil nitrogen, corn yield, and nitrogen loss?

Reducing nitrogen with boron and beer
The industrial conversion of nitrogen to ammonium provides fertiliser for agriculture.

New nitrogen products are in the air
A nifty move with nitrogen has brought the world one step closer to creating a range of useful products -- from dyes to pharmaceuticals -- out of thin air.

'Black nitrogen'
In the periodic table of elements there is one golden rule for carbon, oxygen, and other light elements.

A deep dive into better understanding nitrogen impacts
This special issue presents a selection of 13 papers that advance our understanding of cascading consequences of reactive nitrogen species along their emission, transport, deposition, and the impacts in the atmosphere.

How does an increase in nitrogen application affect grasslands?
The 'PaNDiv' experiment, established by researchers of the University of Bern on a 3000 m2 field site, is the largest biodiversity-ecosystem functioning experiment in Switzerland and aims to better understand how increases in nitrogen affect grasslands.

Reducing reliance on nitrogen fertilizers with biological nitrogen fixation
Crop yields have increased substantially over the past decades, occurring alongside the increasing use of nitrogen fertilizer.

Flushing nitrogen from seawater-based toilets
With about half the world's population living close to the coast, using seawater to flush toilets could be possible with a salt-tolerant bacterium.

We must wake up to devastating impact of nitrogen, say scientists
More than 150 top international scientists are calling on the world to take urgent action on nitrogen pollution, to tackle the widespread harm it is causing to humans, wildlife and the planet.

Read More: Nitrogen News and Nitrogen Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.