World Rainforest Movement

Biodiversity also better than monocultures from a climate perspective

Recent research findings provide additional arguments to the opposition movement against the inclusion of tree plantations as carbon sinks within the current Convention on Climate Change debate on the implementation of the Kyoto Protocol.

Researchers from the U.S. Department of Energy’s Brookhaven National Laboratory say that biodiversity is an important factor regulating how ecosystems will respond to increasing atmospheric carbon dioxide. The team of investigators, led by Peter Reich of the University of Minnesota, just released results from a major field study that appears in the April 12 issue of the journal “Nature.”

All plants absorb carbon dioxide as they grow, but different species absorb carbon at different rates –and different environmental conditions can also affect how well plants absorb carbon. The scientists found that more diverse plant ecosystems were better able to absorb carbon dioxide (CO2) and nitrogen, both of which are on the rise due to human activities and industrial processes.

“The key implication of this research is that, in response to elevated levels of CO2 and nitrogen, ecosystems with high biodiversity will take up and sequester more carbon and nitrogen than do ecosystems with reduced biodiversity,” said Brookhaven plant physiologist David Ellsworth, one of the study authors.

The study thus lends credence to arguments that intact ecosystems do a better job of regulating environmental problems than do human-made landscapes such as tree monocultures.

The researchers learned that elevated levels of CO2 and nitrogen resulted in increased biomass when compared with plots exposed to ambient levels of CO2 and nitrogen. The effect, however, was greatest in plots with high biodiversity as compared to those with fewer species.

“These findings suggest that protecting biodiversity worldwide will contribute to safeguarding the capacity of ecosystems to capture a larger fraction of additional carbon and nitrogen entering our environment due to industrial processes,” said Brookhaven ecologist George Hendrey.

Article based on information from: “Biodiversity Gives Carbon Sinks a Boost”, by Cat Lazaroff, ENS