Document: EHL-3-99-174

Scaling physiological ecology in the future.

EHLERINGER, J.R.J.R.* ¹ and M.M.CALDWELL ²

University of Utah, Salt Lake City, UT 84112-1101 USA ¹
Utah State University, Logan, UT 84322-0001 USA ²

Abstract:
Physiological ecology has a rich tradition investigating mechanisms of adaptation between organisms and their environment. Increasingly, our understanding of physiological ecology has proved valuable for addressing larger scale questions related to ecosystem dynamics and biosphere-atmosphere fluxes. The extension of physiological ecology to longer time scales and to larger spatial scales is desirable, but challenging. While the nonlinearities in scaling of processes from individual to ecosystem are appreciated , rules for scaling are elusive. No where is the need for process scaling more apparent than in global change studies, where the focus is on determining how ecosystems are responding to atmospheric, hydrologic, and land-use changes. In this presentation, we examine 3 examples of the melding of physiological ecology and ecosystem ecology: (a) C₃/C₄ photosynthesis in response to atmospheric carbon dioxide and its impacts on productivity and animal diversity, (b) water-resource partitioning, competition, and ecosystem dynamics in arid ecosystems in response to monsoon-boundary shifts, and (c) stable isotope ratios in carbon dioxide fluxes between the biosphere and the atmosphere that allow determination of carbon sources and sinks in different ecosystems and under land-use change activities.

Keywords: Physiological ecology

This abstract is being presented at: 4:30 PM in session:
Symposium # 16: Plant Physiological Ecology: Linking the Organism to Scales Above and Below.