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Harvard Forest Symposium Abstract 2006
- Title: Barre Woods Soil Warming Project: Effects on Biogeochemistry and Forest Trees After Three Years of Warming
- Primary Author: Joe Blanchard (Marine Biological Laboratory)
- Additional Authors: Frank Bowles (Research Designs); Elizabeth Burrows (Rutgers University); Heidi Lux (Harvard Forest); Jerry Melillo (Marine Biological Laboratory); Jacqueline Mohan (University of Georgia); Paul Steudler (Marine Biological Laboratory)
- Abstract:
Temperate-zone forests of the Northern Hemisphere are currently important sinks for atmospheric carbon dioxide. Whether or not they will continue to act as carbon sinks in a warmer world depends in large part on a complex set of plant and soil responses to global climate change. In a stand of mixed hardwoods at the Harvard Forest in central Massachusetts, USA, we have been studying some of these plant and soil responses in a large field experiment (30 x 30m plots) where soils have been heated 5°C above ambient. Over the first three years of the study, we observed two major ecosystem responses to soil warming that feed back to the climate system; a loss of carbon as carbon dioxide from soils, and an increase in the growth rate of trees that is leading to increased carbon storage in woody tissue. The increase in tree growth in response to warming appears to be related to both a lengthening of the growing season and an increase in the amount of soil nitrogen that becomes available to the trees each year. Since the start of the experiment, about 60% more carbon has been released from soils than has been stored in new wood growth. Based on our earlier soil warming research at the Harvard Forest, we hypothesize that over the next decade, the stimulation of carbon losses from soils by warming will cease, while warming will continue to stimulate carbon storage in the trees.
- Research Category: Large Experiments and Permanent Plot Studies
Soil Carbon and Nitrogen Dynamics
