August 8, 2013

Study Questions Nature’s Ability To ‘Self-Correct’ Climate Change



By performing tests on subtropical woodland plots over an 11-year period, the researchers found that ecosystem carbon uptake was not significantly increased by the high CO2 treatmentâ€”in contrast to expectations. While plants did contain more carbon when CO2 levels were increased, soil actually lost carbon due to microbial decomposition; both factors essentially balanced one another out.

"Nature cannot 'self-correct' entirely against climate change, and the scientific community has been both overestimating the impact of plants and underestimating the impact of soil microorganisms in how they absorb CO2 and ultimately impact global warming," said Bruce Hungate, director of the Center for Ecosystem Science and Society at NAU and lead author on the study.

"Models of land ecosystems need to be revised to represent microbial responses explicitly," Hungate said. "They're the carbon balance 'trump card,' reversing the effect of plants on total carbon storage."


In addition, the study results indicate that widely accepted carbon cycle models overestimate the role of ecosystems in absorbing carbon from the atmosphere because the models do not represent the responses of soil microorganisms correctly.


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