Elevated CO2 levels may mitigate losses of biodiversity from nitrogen pollution

December 3, 2009

Rising levels of carbon dioxide may overheat the planet and cause other environmental problems, but fears that rising CO2 levels could directly reduce plant biodiversity can be allayed, according to a new study by a University of Minnesota scientist Peter Reich. In fact, rising CO2 may actually help counteract losses of diversity from another environmental villain: the global rain of nitrogen from fertilizers and exhaust fumes.

The study, published in this week's edition of Science magazine, involved a 10-year open-air outdoor experiment in which 48 plots planted with 16 different species of plants were tested using ambient and elevated levels of nitrogen and carbon dioxide. Researchers measured the number of species observed in each plot, the plant biomass both above and below ground, as well as factors related to soil, water and light that might affect plant growth.

Over time, the diversity of plants growing in the research plots changed significantly, depending on the combinations of plants and the way added CO2 and nitrogen affected the health of different species. One of the study's key findings is that while the combination of ambient and nitrogen pollution reduces by 16 percent, adding more CO2 to the mix reduces that change by half.

"From a biodiversity perspective, there was no evidence to support the worst-case scenario, in which impacts of rising CO2 and combine to suppress diversity by 30 percent, 40 percent or even 50 percent or more," Reich said. "Instead, their interaction ameliorated the diversity loss due to nitrogen enrichment that occurs under ambient CO2. Given the importance of biodiversity to the effective health and function of our ecosystems this is good news, or perhaps better labeled as "not quite as bad" news".

Reich, a Regents professor in the department of forest resources, notes that "while it is a relief to find out that rising CO2 and may not directly cause enormous losses of diversity, this finding does not detract from the urgent need for us to curb CO2 emissions given the other critical CO2 effects, such as overheating the planet and threatening marine life through ocean acidification."

Source: University of Minnesota (news : web)

Explore further: Rule reveals CO2 emissions of plant life

Related Stories

Rule reveals CO2 emissions of plant life

January 26, 2006

Minnesota researchers have found a universal rule regulating plant metabolism that may also offer a key to calculating plants' carbon dioxide emissions.

Too much water, fertilizer bad for plant diversity

March 26, 2007

Too much of multiple good things -- water or nutrients, for example -- may decrease the diversity of plant life in an ecosystem while increasing the productivity of a few species, a UC Irvine scientist has discovered.

Recommended for you

Mysterious deep-Earth seismic signature explained

November 22, 2017

New research on oxygen and iron chemistry under the extreme conditions found deep inside the Earth could explain a longstanding seismic mystery called ultralow velocity zones. Published in Nature, the findings could have ...


Adjust slider to filter visible comments by rank

Display comments: newest first

3 / 5 (4) Dec 03, 2009
From a biodiversity perspective, there was no evidence to support the worst-case scenario, in which impacts of rising CO2 and nitrogen deposition combine to suppress diversity by 30 percent, 40 percent or even 50 percent or more

Yet another wing of that house of cards goes down. Whattaya got left AGW?
overheating the planet

LOL! He knows the earth has had CO2 levels an order of magnitude higher than now and been completely without polar ice, for eons, in the earth's past, right? And it seemed to do alright after all that, seeing as that's where all present life arose from.
threatening marine life through ocean acidification

This would be worth worrying about if massive marine extinctions hadn't been occurring with regularity for the past 500 million years.

What REALLY threatens marine life is overfishing and actual pollution, for instance that Texas sized patch of plastic floating in the Pacific, maybe the AGW theorists haven't heard about that.
1 / 5 (1) Dec 04, 2009
You can be sure that the results of this excellent study will be ignored by the believers and they will continue to quote the higher guesses, classic cult modus operandi.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.