"We'll be working at a site north of Duluth, Minnesota, where we've designed experiments to simulate the effect of global warming on natural bogs and fens," said Dr. Jiquan Chen of Michigan Tech's School of Forestry and Wood Products. "We want to see how increased temperatures and moisture affect ecosystem productivity and biodiversity."

The major objective of the study is to examine the interactions between plant community composition and dynamics, whole-ecosystem carbon exchange, and the radiative and thermal energy balance of northern peatlands under a changing climate.

"The central hypothesis," said Chen, "is that climate caused heat loading and water-table depth will determine plant community and ecosystem structure and function in peatlands, which in turn will have a feedback effect on the energy budget of the system. Thus, the same amount of heat applied to two different ecosystems won't necessarily lead to similar ecosystem temperatures. There is a degree of biotic control over temperature, and this project will determine the mechanisms and quantitative effects of that phenomenon. In turn, temperature does have a strong effect on many ecosystem processes."

Chen said previous studies have raised the possibility that global warming might result in a lack of physical energy for natural ecosystems and that species richness abundance could change depending on how different species react to higher temperatures and moisture. "This could mean changes in the endangered species list," he said.

On the other hand, architectural changes in the plant community canopy caused by global warming might significantly affect the energy budget, depending on an ecosystem's resilience to changing conditions, according to Che
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Contact: Dr. Jiquan Chen
jiq@mtu.edu
906-487-3432
Michigan Technological University
3-Sep-1997