Navigation Links
Too much of a good thing? Excess nutrients or water limit biodiversity

Too much of a good thing (nutrients or water) actually decreases the diversity of species in an ecosystem while it increases the productivity of a few species, according to a grassland experiment conducted by University of Minnesota researchers.

The reduction in species diversity occurs because increasing the amounts of limiting resources, such as nitrogen and water, makes an ecosystem more homogeneous and consequently reduces the number of opportunities for competing species to coexist. Put another way, it reduces the number of niches, allowing a few species to dominate.

The study, conducted by David Tilman, Regents Professor of Ecology, and Stanley Harpole will be published March 25 in the online version of the journal Nature. Harpole, who is now a postdoctoral associate at the University of California, Irvine, was a graduate student at the University of Minnesota when the research was carried out.

"In essence, the data in the article strongly supports a new explanation for why the world contains so many species," said Tilman. "It shows that plant diversity is directly related to the number of limiting factors (such as soil moisture, nitrogen, phosphorous, potassium and water)."

It also helps explain why grasslands, lakes and rivers that are polluted with nitrogen and phosphorous (usually from agriculture) have fewer species. The reduction of species where the Mississippi River empties into the Gulf of Mexico is one of the best known examples of this phenomenon.

The findings are based on experiments carried out at the University of California’s Sedgwick Reserve in the Santa Ynez Valley, where the researchers applied combinations of nutrients and water to plots of grassland. Plots that received all of the resources had the fewest species and highest productivity. They combined this with analysis of the 150 year old Rothamsted Park Grass Experiment. Both supported their hypothesis.

"Our results show that the loss of plant species from a habitat due to nutrient pollution can persist for more than 100 years," Harpole said. "Thus human actions that simplify habitats can lead to long-term loss of biodiversity."

Source:University of Minnesota

Related biology news :

1. How exactly does the brain control breathing?
2. Excess liver gene protects against high-fat diet
3. Mechanism for the captation of nutrients in plants- unknown to date
4. Fish extinctions alter critical nutrients in water, study shows
5. Anti-bacterial additive widespread in U.S. waterways
6. Unprecedented water level rise in Somalia
7. Microbial fuel cell: High yield hydrogen source and wastewater cleaner
8. Survey finds silver contamination in North Pacific waters
9. Researchers discover underwater volcano
10. Too much water may be as dangerous as too little during long-distance athletic events
11. Radio-tracking associated with dramatic shift in water vole sex ratio

Post Your Comments:

(Date:11/18/2015)... 18, 2015 --> ... new market report titled  Gesture Recognition Market - Global ... - 2021. According to the report, the global gesture recognition market was ... to reach US$29.1 bn by 2021, at a CAGR ... North America dominated the global gesture recognition ...
(Date:11/17/2015)... Paris , qui s,est tenu ... Paris , qui s,est tenu du 17 au ... l,innovation biométrique, a inventé le premier scanner couplé, qui ... même surface de balayage. Jusqu,ici, deux scanners étaient nécessaires, ... digitales. Désormais, un seul scanner est en mesure de ...
(Date:11/17/2015)... Pressure BioSciences, Inc. (OTCQB: PBIO) ("PBI" and ... of broadly enabling, pressure cycling technology ("PCT")-based sample preparation ... it has received gross proceeds of $745,000 from an ... "Offering"), increasing the total amount raised to date in ... are expected in the near future. ...
Breaking Biology News(10 mins):
(Date:12/1/2015)... 2015 Today the Allen Institute announced the ... South Lake Union neighborhood, the city,s biotechnology ... and Westlake Avenue North, the 270,000 square foot life ... Brain Science and the Allen Institute for Cell Science. ... of the Allen Institute. "We started by building a ...
(Date:12/1/2015)... Dec. 1, 2015 Frost & Sullivan ... This program addresses ways companies can innovate and ... --> ... --> ... as well as the disrupting factors altering the ...
(Date:12/1/2015)... 01, 2015 ... the "2016 Europe Cell Surface Markers: ... Competitive Strategies, Opportunities for Suppliers--France, Germany, Italy, ... --> ) has announced ... Cell Surface Markers: Country Volume and Sales ...
(Date:12/1/2015)... (PRWEB) , ... December 01, 2015 , ... ... provider, announces that its best selling system laboratory animal colony management software solution, ... today, without investing in on-site IT resources., , Many ...
Breaking Biology Technology: