Navigation Links
Streams remove significant amounts of nitrogen, preventing downstream 'dead zones'
Date:3/12/2008

DURHAM, N.H. Small streams play a significant role in retaining human-generated nitrogen, serving as the kidneys of watersheds by removing nitrogen before it ends up in estuaries and oceans, finds a paper published this week in the journal Nature. University of New Hampshire professor William McDowell and research scientist Jody Potter, both in the department of natural resources, are among the co-authors of the study, led by Patrick Mulholland of the Oak Ridge National Laboratory in Tenn.

The major finding is that streams remove significant amounts of nitrogen thats coming off the landscape, says McDowell, noting that human-generated activities such as agricultural runoff, acid rain, and the human waste stream are major sources of nitrogen. But while this process of denitrification a bacterial process that converts nitrogen to a harmless nitrogen gas -- cleans up waterways, if we overuse it by putting too much nitrogen into the water its not as effective.

Nitrogen removal in streams is important because it reduces the potential for eutrophication the excessive growth of algae and aquatic plants in downstream lakes and coastal marine waters. Eutrophication is linked to problems such as harmful algal blooms and oxygen depletion in places such as the Gulf of Mexico, where the Mississippi River creates a vast dead zone of oxygen depletion with adverse effects on fisheries.

A key finding of the study, titled Stream denitrification across biomes and its response to anthropogenic nitrate loading, is that the effectiveness of streams to remove nitrate was greatest if the streams were not overloaded by nitrogen sources such as fertilizers and wastes from human activities. The largest percentage removal occurred when nitrate entered small healthy streams and traveled throughout the network before reaching larger rivers. As terrestrial ecosystems become increasingly saturated with nitrogen as a result of human activities, the authors caution that large-scale land conversion may negatively impact streams ability to effectively remove nitrogen from the watershed.

The study, which undertook a huge field campaign to investigate nitrogen uptake and denitrification in 72 streams that drain watersheds of varying land-use types in the U.S. and Puerto Rico, is the first continental-scale assessment of total denitrification in small streams. McDowell oversaw field sites in Puerto Rico and Potter, who at the time of the study was McDowells graduate student, worked in both Puerto Rico and Massachusetts.

The study is also unique in that it captures the entire denitrification process, measuring not only the production of nitrous oxide but also N2, a harmless gas that is prevalent in the Earths atmosphere.

Moving forward, McDowell notes that this study will inform the work of the National Ecological Observatory Network (NEON), of which he and several other UNH researchers are a part. McDowell will undertake long-term experimental manipulations of streams, adding nutrients to streams in a controlled way.

He also notes that the breadth of this project will carry forward. Weve developed this network of stream ecologists, and we can now answer questions at the continental scale, he says.


'/>"/>

Contact: Beth Potier
beth.potier@unh.edu
603-862-1566
University of New Hampshire
Source:Eurekalert

Related biology news :

1. From the backyard to the ocean: New study shows streams act as key nitrogen filters
2. Small streams mitigate human influence on coastal ecosystems
3. Scientists show that streams are critical to preservation of oceanic coastal zones
4. Salamanders, headwater streams critical in food chain
5. New research offers prioritization plan for reducing nutrient pollution in feeder streams
6. Greenhouse gas from English streams
7. Healthy rivers needed to remove nitrogen
8. Scientists discover novel way to remove iron from ferritin
9. M2SYS Introduces Revolutionary Biometric Artificial Intelligence Technology to Significantly Reduce Fingerprint Software False Reject Rates
10. Stanford researchers say climate change will significantly increase impending bird extinctions
11. Columbia researchers: Growth of CT scan use may lead to significant public health problem
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/5/2017)... KEY FINDINGS The global market for stem ... 25.76% during the forecast period of 2017-2025. The rise ... growth of the stem cell market. Download ... The global stem cell market is segmented on the ... cell market of the product is segmented into adult ...
(Date:3/30/2017)... HONG KONG , March 30, 2017 ... developed a system for three-dimensional (3D) fingerprint identification by adopting ground ... technology into a new realm of speed and accuracy for use ... applications at an affordable cost. ... ...
(Date:3/27/2017)... CENTRE, N.Y. , March 27, 2017 /PRNewswire-USNewswire/ ... Healthcare Information and Management Systems Society (HIMSS) Analytics ... Outpatient EMR Adoption Model sm . In addition, ... 12% of U.S. hospitals using an electronic medical ... CHS for its high level of EMR usage ...
Breaking Biology News(10 mins):
(Date:4/25/2017)... ... April 25, 2017 , ... As part of the Stago ... the laboratory testing for DIC in order to illuminate this clinical problem for people ... in hospitalized patients resulting in a high degree of morbidity and mortality. DIC is ...
(Date:4/25/2017)... (PRWEB) , ... April 25, 2017 , ... ... Services and Metrology Partners.     , Covalent’s Analytical Services unit provides high-quality ... can be measured within 24 hours of receipt. There are no price premiums, ...
(Date:4/21/2017)... ... 2017 , ... Having worked on the design of the innovative Triton™ ... to top lab design architects from around the country at the Lab Design Conference ... and Engineering Greg Casey will be at the show, where they will highlight the ...
(Date:4/21/2017)... ... 2017 , ... Frederick Innovative Technology Center, Inc. (FITCI), a ... recently earned a $77,518 grant from the Rural Maryland Council (RMC) to support ... Frederick’s first incubator. A non-profit corporation, FITCI is a public-private partnership of the ...
Breaking Biology Technology: