Navigation Links
ORNL study finds rivers play part in removing nitrogen

OAK RIDGE, Tenn., March 12, 2008 Tiny organisms play a powerful role in removing nitrate, a form of nitrogen pollution caused by human activity, in streams, according to a study by a team led by Oak Ridge National Laboratory and published in Nature.

In the first phase of the study, which involved 31 aquatic scientists from across the United States, researchers added small amounts of an uncommon non-radioactive isotope of nitrogen to 72 streams across the U.S. and Puerto Rico. Using this tracer, the teams objective was to measure how far downstream the nitrate traveled and how it was removed from water.

We found that the nitrate was filtered from stream water by tiny organisms such as algae, fungi and bacteria, said Patrick Mulholland, lead author of the study and a member of Oak Ridge National Laboratorys Environmental Sciences Division. Mulholland has a joint appointment at the University of Tennessee.

The researchers also found that a considerable amount of nitrate was removed from streams by a bacterially mediated process known as denitrification, which converts nitrate to nitrogen gas. That gas then escapes harmlessly to the atmosphere, Mulholland said.

In the second phase of the study, the scientists developed a model to study nitrate removal from water within river networks. These networks develop as small streams flow into larger streams and rivers.

Our model showed that the entire stream network is important in removing pollution from stream water, Mulholland said. In addition, the effectiveness of streams to remove nitrate was greatest if the streams were not overloaded by pollutants such as fertilizers and wastes from human activities.

The largest removal occurred when nitrate entered small healthy streams and traveled throughout the network before reaching large rivers. The scientists concluded from their research that streams and rivers are effective filters that can help prevent nitrate pollution from reaching lakes and the coastal waters where this type of pollution can cause noxious algal blooms and lead to oxygen depletion and death of fish and shellfish.


Contact: Ron Walli
DOE/Oak Ridge National Laboratory

Related biology news :

1. Childhood obesity indicates greater risk of school absenteeism, Penn study reveals
2. A study by the MUHC and McGill University opens a new door to understanding cancer
3. Study begins to reveal clues to the cause and progression of sepsis
4. Clones on task serve greater good, evolutionary study shows
5. New study warns limited carbon market puts 20 percent of tropical forest at risk
6. New study examines how rearing environment can alter navigation
7. Study links cat disease to flame retardants in furniture and to pet food
8. New continent and species discovered in Atlantic study
9. Study shows link between alcohol consumption and hiv disease progression
10. Feeling hot, hot, hot: New study suggests ways to control fever-induced seizures
11. Study finds environmental tests help predict hospital-acquired Legionnaires disease risk
Post Your Comments:
(Date:3/31/2016)...   LegacyXChange, Inc. ... LegacyXChange is excited to release its first ... be launched online site for trading 100% guaranteed authentic ... also provide potential shareholders a sense of the value ... industry that is notorious for fraud. The video is ...
(Date:3/29/2016)... 2016 LegacyXChange, Inc. (OTC: ... SelectaDNA/CSI Protect are pleased to announce our successful effort ... variety of writing instruments, ensuring athletes signatures against counterfeiting ... from athletes on LegacyXChange will be assured of ongoing ... Bill Bollander , CEO states, "By ...
(Date:3/22/2016)... India , March 22, 2016 /PRNewswire/ ... market research report "Electronic Sensors Market for Consumer ... Proximity, & Others), Application (Communication & IT, ... Geography - Global Forecast to 2022", published ... industry is expected to reach USD 26.76 ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... 23, 2016   EpiBiome , a precision microbiome ... in debt financing from Silicon Valley Bank (SVB). The ... to advance its drug development efforts, as well as ... "SVB has been an incredible strategic partner to ... traditional bank would provide," said Dr. Aeron Tynes ...
(Date:6/23/2016)... ... ... STACS DNA Inc., the sample tracking software company, today announced that Dr. ... STACS DNA as a Field Application Specialist. , “I am thrilled that Dr. ... STACS DNA. “In further expanding our capacity as a scientific integrator, Hays brings a ...
(Date:6/23/2016)... , June 23, 2016 Apellis Pharmaceuticals, ... 1 clinical trials of its complement C3 inhibitor, ... and multiple ascending dose studies designed to assess ... of subcutaneous injection in healthy adult volunteers. ... either as a single dose (ranging from 45 ...
(Date:6/23/2016)... LONDON , June 23, 2016 ... & Hematology Review, 2016;12(1):22-8 ... Review , the peer-reviewed journal from touchONCOLOGY, ... the escalating cost of cancer care is placing ... a result of expensive biologic therapies. With the ...
Breaking Biology Technology: