Grazing management effects on stream pollutants

Scientists study the effects of grazing management practices on sediment, phosphorus, and harmful bacteria deposits into pasture streams

2011-07-22

(Press-News.org) MADISON, WI, JULY 21, 2011 -- Surface water quality is important for the proper function of aquatic ecosystems, as well as human needs and recreation. Pasturelands have been found to be major sources of sediment, phosphorus and pathogens in Midwest surface water resources. While poor grazing management may lead to contaminated surface water, little is known about the specific amount of pollution in pasture streams that can be attributed to grazing cattle.

Scientists in the Departments of Animal Science, Veterinary Diagnostic and Production Animal Medicine, and Veterinary Microbiology at Iowa State University and the USDA-ARS National Laboratory for Agriculture and the Environment have studied the effects of grazing management practices on sediment, phosphorus, and pathogen deposits into pasture streams. Results of the study are published in the July/August 2011 issue of the Journal of Environmental Quality.

There were no differences in the amounts of sediment, phosphorus or pathogen deposits in the pasture stream between the different types of stream access given to the cattle. Most of the phosphorus and sediment introduced to the stream was the result of stream bank erosion.

The levels of pathogens cattle deposited into pasture streams were infrequent, and found to be dependent on the distribution of grazing cattle. The amount of pollutants in pasture streams were estimated from six 30-acre pastures in central Iowa for two years. The cattle were given different types of access to the pasture streams. Pollutants transported in precipitation runoff was quantified, and fecal samples were collected and analyzed for their levels of harmful bacteria.

Kirk Schwarte, the graduate student who conducted the study, explains, "While cattle can certainly contribute to the pollution of the streams, implementing simple and practical grazing management practices have the potential to greatly reduce these contributions while continuing to allow the cattle to have controlled access to graze on pasture stream banks."

Research on the relationship between grazing cattle and the pollution contributed by the cattle of pasture streams is ongoing at Iowa State University. Further research of grazing management techniques includes the evaluation of specific management practices to maintain water quality in pasture streams.

### This research was funded with grants from the USDA Cooperative State Research, Education, and Extension Service National Integrated Water Program and National Research Initiative.

The full article is available for no charge for 30 days following the date of this summary. View the abstract at https://www.agronomy.org/publications/jeq/articles/40/4/1303.

The Journal of Environmental Quality is a peer-reviewed, international journal of environmental quality in natural and agricultural ecosystems published six times a year by the American Society of Agronomy (ASA), Crop Science Society of America (CSSA), and the Soil Science Society of America (SSSA). The Journal of Environmental Quality covers various aspects of anthropogenic impacts on the environment, including terrestrial, atmospheric, and aquatic systems.

The American Society of Agronomy (ASA) www.agronomy.org, is a scientific society helping its 8,000+ members advance the disciplines and practices of agronomy by supporting professional growth and science policy initiatives, and by providing quality, research-based publications and a variety of member services.

The Soil Science Society of America (SSSA) is a progressive, international scientific society that fosters the transfer of knowledge and practices to sustain global soils. Based in Madison, WI, SSSA is the professional home for 6,000+ members dedicated to advancing the field of soil science. It provides information about soils in relation to crop production, environmental quality, ecosystem sustainability, bioremediation, waste management, recycling, and wise land use.

SSSA supports its members by providing quality research-based publications, educational programs, certifications, and science policy initiatives via a Washington, DC, office. Founded in 1936, SSSA celebrates its 75th Anniversary this year (2011). For more information, visit www.soils.org or follow @SSSA_soils on Twitter.

The Crop Science Society of America (CSSA), founded in 1955, is an international scientific society comprised of 6,000+ members with its headquarters in Madison, WI. Members advance the discipline of crop science by acquiring and disseminating information about crop breeding and genetics; crop physiology; crop ecology, management, and quality; seed physiology, production, and technology; turfgrass science; forage and grazinglands; genomics, molecular genetics, and biotechnology; and biomedical and enhanced plants.

CSSA fosters the transfer of knowledge through an array of programs and services, including publications, meetings, career services, and science policy initiatives. For more information, visit www.crops.org.

ELSE PRESS RELEASES FROM THIS DATE:

Elimination of national kidney allocation policy improves minority access to transplants

2011-07-22

A new study published in the American Journal of Transplantation reveals that since the elimination of the kidney allocation priority for matching for HLA-B on May 7, 2003, access to kidney transplantation for minorities has been improved. Improvement is a result of a policy that reduced the requirements for tissue matching. Prior national kidney allocation rules provided priority to candidates who shared HLA-B antigens with potential deceased donors. On May 7, 2003, allocation priority for HLA-B matching was eliminated. Improvements in medications used to prevent transplant ...

Researchers stumble on colorful discovery

2011-07-22

Modified metals that change colour in the presence of particular gases could warn consumers if packaged food has been exposed to air or if there's a carbon monoxide leak at home. This finding could potentially influence the production of both industrial and commercial air quality sensors. "We initially found out by accident that modified rhodium reacts in a colourful way to different gases," says Cathleen Crudden, a professor in the Department of Chemistry. "That happy accident has become a driving force in our work with rhodium." Rhodium that is modified using carbon, ...

UCI-led butterfly study sheds light on convergent evolution

2011-07-22

Irvine, Calif., July 21, 2011 – For 150 years scientists have been trying to explain convergent evolution. One of the best-known examples of this is how poisonous butterflies from different species evolve to mimic each other's color patterns – in effect joining forces to warn predators, "Don't eat us," while spreading the cost of this lesson. Now an international team of researchers led by Robert Reed, UC Irvine assistant professor of ecology & evolutionary biology, has solved part of the mystery by identifying a single gene called optix responsible for red wing color ...

Minority participants crucial to effective aging studies

2011-07-22

A new supplemental issue of The Gerontologist urges aging researchers to include representative samples of ethnically diverse populations in their work. The publication also identifies research priorities for moving the science of recruitment and retention forward, in addition to providing several strategies that scholars can employ in their work. The U.S. Census Bureau predicts that non-white minorities will make up 42 percent of the country's 65-and-over population by 2050. "The cultural-historical background and sociopolitical conditions of each diverse group poses ...

Exoplanet aurora: An out-of-this-world sight

2011-07-22

VIDEO: In this animation, stunning aurorae ripple around a "hot Jupiter. " When a stellar eruption known as a coronal mass ejection hit the planet, it triggered these aurorae, which are the... Click here for more information. Earth's aurorae, or Northern and Southern Lights, provide a dazzling light show to people living in the polar regions. Shimmering curtains of green and red undulate across the sky like a living thing. New research shows that aurorae on ...

Forest fungus factory

2011-07-22

An invasive insect, hemlock woolly adelgid, has been marching north along the Appalachians, killing almost every hemlock tree in its path. The adelgid has devastated forests in Georgia, Tennessee, and Virginia. The pest recently arrived in Vermont and other parts of New England. So far, only extreme cold stops the adelgid. But now a University of Vermont scientist has developed what he calls a "fungal microfactory" technology that promises to give forest managers and homeowners a tool to fight back. Working with the U.S. Forest Service, the State of Vermont, and others, ...

Hepatitis C is transmitted by unprotected sex between HIV-infected men

2011-07-22

Sexual transmission of hepatitis C virus (HCV) is considered rare. But a new study by researchers at Mount Sinai School of Medicine, working with the Centers for Disease Control and Prevention (CDC), provides substantial evidence that men with HIV who have sex with other men (MSM) are at increased risk for contracting HCV through sex. The results of the study are published in today's edition of the CDC's Morbidity and Mortality Weekly Report. HCV transmission primarily occurs through exposure to blood, and persons who inject drugs at greatest risk. But when Mount Sinai ...

Paternity testing helps fill in family tree for Puget Sound's killer whales

2011-07-22

In a study published online this month in the Journal of Heredity, NOAA researchers and others, using DNA testing to fill in a missing link in the lives of killer whales that seasonally visit Washington's Puget Sound, have discovered that some of the progeny they studied were the result of matings within the same social subgroups, or pods, that are part of the overall population. One implication of this inbreeding behavior is a significant reduction in the genetic diversity of what is already a perilously small population of animals, formally known as Southern Resident ...

Hospital bacteria outbreak linked to nasal spray

2011-07-22

Chicago, IL—Infection control researchers investigating a rare bacterial outbreak of Burholderia cepacia complex (Bcc) identified contaminated nasal spray as the root cause of the infections, leading to a national recall of the product. An article in the August issue of Infection Control and Hospital Epidemiology, the journal of the Society for Healthcare Epidemiology of America (SHEA), describes how researchers were able to trace the outbreak back to the nasal decongestant spray. Bcc is a group of Gram-negative bacteria that can cause hard-to-treat infections. Patients ...

Hepatitis B vaccination for health care students lags behind recommendations

2011-07-22

Chicago, IL (July 21, 2011)—A study in the August issue of Infection Control and Hospital Epidemiology, the journal of the Society for Healthcare Epidemiology of America (SHEA), suggests that documentation of hepatitis B vaccination for health care students may fall short of current recommendations. Researchers led by Dr. Rania Tohme of the Centers for Disease Control and Prevention (CDC) analyzed hepatitis B immunization records of 4,075 health care students who matriculated at a university in the southeastern U.S. between January 2000 and January 2010. The study found ...

Grazing management effects on stream pollutants

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: