Featured Research

from universities, journals, and other organizations

Complex relationship between phosphorus levels, nitrogen removal in lakes

Date:
October 10, 2013
Source:
University of Minnesota
Summary:
In the land of 10,000 lakes, one lake has been the starting place for research with implications for big lakes around the world. Building from studies of nitrogen levels in Lake Superior, the new research uncovered a good news/bad news scenario for lake health that has long-term, global implications for pollution control efforts.

In the land of 10,000 lakes, one lake has been the starting place for research with implications for big lakes around the world. According to a study published online this week in Science, University of Minnesota researchers, building from studies of nitrogen levels in Lake Superior, uncovered a good news/bad news scenario for lake health that has long-term, global implications for pollution control efforts.

While many water-quality cleanup efforts focusing on the reduction of phosphorus have been highly effective, that success can also result in a decrease in microbial processes that remove nitrogen from water. Nitrogen accumulation in large lakes can lead to nitrogen pollution downstream, in rivers and coastal areas. The findings suggest that human-caused acceleration of global nitrogen and phosphorus cycles have boosted nitrogen removal processes in small to medium-size lakes. But in many of Earth's large lakes, these effects are reduced by successful control of phosphorus, resulting in nitrogen accumulation.

"Freshwater ecosystems, including lakes, streams and wetlands, are a large global sink for reactive nitrogen," says lead author Jacques Finlay, an associate professor in the College of Biological Sciences (CBS). "By reducing one aquatic pollutant -- phosphorus -- we are in some cases reducing the ability of lakes to remove nitrogen." Gaston Small, an assistant professor at the University of St. Thomas, and Robert Sterner, a fellow CBS ecology professor, co-authored the study.

To assess the influence of phosphorus on nitrogen removal, the researchers used a comparative approach -- they examined the differences between how much nitrogen goes into lakes and how much comes out downstream -- coupled with time-series analyses of nitrogen and phosphorus concentration in large lakes.

"The work was motivated by our thinking about the case of a single lake -- Lake Superior. This lake is one that we would expect to efficiently remove nitrogen, but it doesn't, and it has extremely low phosphorus, so this work arose from efforts to generalize beyond a single system," Finlay says.

The excess nutrients can come from a variety of sources. City dwellers contribute nitrogen through sewage, lawn fertilizer, vehicle exhaust and pets. Farming represents the largest source in agricultural areas, and, in remote areas, air pollutants dispersing through the atmosphere can be a factor.

The study does not suggest we stop reducing phosphorus in lakes. "We need to pay attention to the way that nutrients interact in ecosystems and maintain our focus on reducing phosphorus and nitrogen pollution," says Finlay. "If we do that, we'll be taking steps toward improving water quality locally as well as downstream."


Story Source:

The above story is based on materials provided by University of Minnesota. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. C. Finlay, G. E. Small, R. W. Sterner. Human Influences on Nitrogen Removal in Lakes. Science, 2013; 342 (6155): 247 DOI: 10.1126/science.1242575

Cite This Page:

University of Minnesota. "Complex relationship between phosphorus levels, nitrogen removal in lakes." ScienceDaily. ScienceDaily, 10 October 2013. <www.sciencedaily.com/releases/2013/10/131010142924.htm>.
University of Minnesota. (2013, October 10). Complex relationship between phosphorus levels, nitrogen removal in lakes. ScienceDaily. Retrieved July 26, 2014 from www.sciencedaily.com/releases/2013/10/131010142924.htm
University of Minnesota. "Complex relationship between phosphorus levels, nitrogen removal in lakes." ScienceDaily. www.sciencedaily.com/releases/2013/10/131010142924.htm (accessed July 26, 2014).

Share This




More Earth & Climate News

Saturday, July 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Virginia Governor Tours Tornado Aftermath

Virginia Governor Tours Tornado Aftermath

AP (July 25, 2014) Virginia Gov. Terry McAuliffe toured the Cherrystone Family Camping and RV Resort on the Chesapeake Bay today, a day after it was hit by a tornado. The storm claimed two lives and injured dozens of others. (July 25) Video provided by AP
Powered by NewsLook.com
Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Bill Gates: Health, Agriculture Key to Africa's Development

Bill Gates: Health, Agriculture Key to Africa's Development

AFP (July 24, 2014) Health and agriculture development are key if African countries are to overcome poverty and grow, US software billionaire Bill Gates said Thursday, as he received an honourary degree in Ethiopia. Duration: 00:36 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins