Soil microbes as predictors of ecosystem functional responses to global climate change

摘要: The world’s soils are a major carbon pool. Continued increases in atmospheric greenhouse gas concentrations are predicted to increase average global surface temperatures by at least 1-6 ºC by 2100 and alter the distribution of precipitation across ecosystems. These changes will alter the distribution of plants as well as the soil microbial communities associated with them. Shifts in plant and microbial communities will alter the pool of terrestrial carbon by changing the input (uptake by plants) and release (decomposition rates of soil organic matter by microbes) of carbon from ecosystems. Soil microbial communities are directly responsible for the mineralization of soil carbon and are linked to plant processes such as root exudation and detrital input. Hence, understanding the links among plant and microbial community composition and function and soil processes is a major theme in ecosystem and global change ecology. Our inability to decouple plant and soil microbial responses decreases our ability to predict and model whether soils in terrestrial ecosystems will be a net source of carbon to, or sink of carbon from, the atmosphere. This talk will present results from three different climate change experiments, a multifactor experiment (CO 2× warming× precipitation) in a Tennessee old-field ecosystem, a warming experiment in a Colorado alpine meadow, and precipitation manipulation in a semi-arid New Mexico pinyon-juniper woodland and a meta analysis to explore how changes in plant and soil communities impact the functional response of ecosystems to global change.