Tuesday, August 3, 2010 - 10:30 AMSYMP 6-9: Managed ecosystem responses to climate extremes: current approaches and future directions
Carl J. Bernacchi, University of Illinois/USDA-ARS
Background/Question/Methods
Many managed ecosystems consist of a single species planted in uniform distributions over large swaths of land. The response of a managed ecosystem to a change in the environment will be driven by the response of the dominant species. Thus, when presented with an extreme event, namely high temperature and/or drought, managed ecosystems will likely respond in a rapid and uniform manner. Given the lack of species, and in many cases genetic, diversity, might ecosystem responses to climate extremes be accentuated relative to unmanaged ecosystems? How might future atmospheric change (e.g., increased CO2) influence the response of agricultural ecosystems to climate extremes? These questions are addressed using ecosystem flux data collected over a variety of managed ecosystems and using data collected as part of the Soybean Free Air CO2 Enrichment experiment in Champaign, IL. The many years of available data provides the opportunity to assess the impacts of naturally occurring climate extremes on the carbon, water, and energy components of various managed ecosystems under current and future atmospheric levels of CO2.
Results/Conclusions
Agricultural statistics data show the responses of managed ecosystems to climate extremes, however these are mostly limited to the impacts on end-of-season agricultural output. The recent expansion of micrometeorological techniques to a variety of ecosystems provides the opportunity to demonstrate how biogeochemical fluxes associated with these ecosystems respond to climate extremes. Multiple years of data collected from SoyFACE demonstrates the impacts of naturally and artificially created climate extreme events on various canopy characteristics. General conclusions suggest that elevate CO2 could mitigate some of the detrimental impacts of water stress but augment temperature extremes. Finally, the future opportunities for manipulative experiments focusing on climate extremes for managed ecosystem function will be discussed with some preliminary results.
Many managed ecosystems consist of a single species planted in uniform distributions over large swaths of land. The response of a managed ecosystem to a change in the environment will be driven by the response of the dominant species. Thus, when presented with an extreme event, namely high temperature and/or drought, managed ecosystems will likely respond in a rapid and uniform manner. Given the lack of species, and in many cases genetic, diversity, might ecosystem responses to climate extremes be accentuated relative to unmanaged ecosystems? How might future atmospheric change (e.g., increased CO2) influence the response of agricultural ecosystems to climate extremes? These questions are addressed using ecosystem flux data collected over a variety of managed ecosystems and using data collected as part of the Soybean Free Air CO2 Enrichment experiment in Champaign, IL. The many years of available data provides the opportunity to assess the impacts of naturally occurring climate extremes on the carbon, water, and energy components of various managed ecosystems under current and future atmospheric levels of CO2.
Results/Conclusions
Agricultural statistics data show the responses of managed ecosystems to climate extremes, however these are mostly limited to the impacts on end-of-season agricultural output. The recent expansion of micrometeorological techniques to a variety of ecosystems provides the opportunity to demonstrate how biogeochemical fluxes associated with these ecosystems respond to climate extremes. Multiple years of data collected from SoyFACE demonstrates the impacts of naturally and artificially created climate extreme events on various canopy characteristics. General conclusions suggest that elevate CO2 could mitigate some of the detrimental impacts of water stress but augment temperature extremes. Finally, the future opportunities for manipulative experiments focusing on climate extremes for managed ecosystem function will be discussed with some preliminary results.