Featured Research

from universities, journals, and other organizations

Tropical rain forests: Humans have more than doubled nitrogen inputs

Date:
May 19, 2014
Source:
The University of Montana
Summary:
Humans have more than doubled tropical nitrogen inputs, according to new research. Scientists used a new method to demonstrate that biological nitrogen fixation in tropical rain forests may be less than a quarter of previous estimates. Nitrogen is an essential nutrient for plant and animal life. Too much nitrogen, however, leads to dead zones, pollutes air and drinking water, contributes to a number of human illnesses, and can affect ecosystems negatively.

A new paper co-written by four University of Montana researchers finds that humans have more than doubled tropical nitrogen inputs.

Benjamin Sullivan, a researcher working with UM College of Forestry and Conservation Professor Cory Cleveland, led the team that looked at the nitrogen cycle in tropical rain forests. Sullivan and his colleagues used a new method to demonstrate that biological nitrogen fixation in tropical rain forests may be less than a quarter of previous estimates.

Nitrogen is an essential nutrient for plant and animal life. It's required in many basic molecules, like DNA and amino acids. Nitrogen enters the environment either through a microbial process called biological nitrogen fixation or through human activity, such as fertilization and fossil-fuel consumption.

Too much nitrogen, however, leads to dead zones, pollutes air and drinking water, contributes to a number of human illnesses, and can affect ecosystems negatively. That could be a problem, given the high biodiversity of tropical rain forests and their important role in the global carbon cycle and the Earth's climate.

"This research fundamentally changes our understanding of the tropical nitrogen cycle," said Sullivan. "It shows that few ecosystems on Earth have escaped the impact of human activity."

He notes that human impacts on the nitrogen cycle typically are greatest where biological nitrogen fixation is low and human inputs of nitrogen are high - like in many parts of North America, including Montana.

Past research has assumed that tropical rain forests have high levels of biological nitrogen fixation and that humans add relatively little nitrogen to tropical ecosystems. In fact, by reducing estimates of naturally occurring nitrogen inputs, "this research shows that human impacts on the nitrogen cycle are even bigger than we thought. Preserving human and ecosystem health requires immediate steps to solve this growing problem," Cleveland said.

Sullivan worked with UM doctoral student Megan Nasto and researcher Bill Smith. Smith provided the spatial data analysis that put Sullivan's field and lab-tested results into a global context. Co-authors also include UM alumna Sasha Reed at the U.S. Geological Survey, and researchers at the University of Colorado-Boulder and the University of Connecticut.


Story Source:

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


Journal Reference:

  1. Benjamin W. Sullivan, W. Kolby Smith, Alan R. Townsend, Megan K. Nasto, Sasha C. Reed, Robin L. Chazdon, and Cory C. Cleveland. Spatially Robust Estimates of Biological Nitrogen (N) Fixation Imply Substantial Human Alteration of the Tropical N Cycle. Proceedings of the National Academy of Sciences, 2014 DOI: 10.1073/pnas.1320646111

Cite This Page:

The University of Montana. "Tropical rain forests: Humans have more than doubled nitrogen inputs." ScienceDaily. ScienceDaily, 19 May 2014. <www.sciencedaily.com/releases/2014/05/140519160801.htm>.
The University of Montana. (2014, May 19). Tropical rain forests: Humans have more than doubled nitrogen inputs. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2014/05/140519160801.htm
The University of Montana. "Tropical rain forests: Humans have more than doubled nitrogen inputs." ScienceDaily. www.sciencedaily.com/releases/2014/05/140519160801.htm (accessed October 2, 2014).

Share This



More Earth & Climate News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Dolphins and Turtles Under Threat in Pakistan

Dolphins and Turtles Under Threat in Pakistan

AFP (Oct. 2, 2014) — The turtles and Dolphins of Pakistan's Indus river - both protected by law - are in a fight for their survival as man's activities threatens their futures. Duration: 02:29 Video provided by AFP
Powered by NewsLook.com
Raw: Japan Volcano Rescue Video Released

Raw: Japan Volcano Rescue Video Released

AP (Oct. 2, 2014) — The Tokyo Fire Department released video of rescue efforts following Saturday's eruption of Mount Ontake in central Japan. It shows firefighters and military troops carrying injured people as plumes of smoke pour from the volcano behind them. (Oct. 2) Video provided by AP
Powered by NewsLook.com
Raw: 12 More Bodies Found on Japan Volcano

Raw: 12 More Bodies Found on Japan Volcano

AP (Oct. 1, 2014) — A dozen more bodies were found Wednesday as Japanese rescuers resumed efforts to find survivors and retrieve bodies of those trapped by Mount Ontake's eruption. (Oct. 1) Video provided by AP
Powered by NewsLook.com
Cultural Learning In Wild Chimps Observed For The First Time

Cultural Learning In Wild Chimps Observed For The First Time

Newsy (Oct. 1, 2014) — Cultural transmission — the passing of knowledge from one animal to another — has been caught on camera with chimps teaching other chimps. Video provided by Newsy
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:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

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