Document: EVI-3-99-171

Linking suites of plant physiological traits to ecosystem dynamics and feedbacks.

EVINER, V.T.* ¹ and F.S.CHAPIN III ²

University of California, Berkeley, CA 94704 ¹
University of Alaska, Fairbanks, AK ²

Abstract:
Plant physiological traits actively influence ecosystem properties such as resource availability and dynamics, disturbance regime, and trophic dynamics. Most previous research has focused on the direct effects of a single plant trait on ecosystem processes. Suites of traits provide the basis for a broader set of generalizations about the effects of changes in species composition on ecosystem dynamics. We present evidence for the following hypotheses: 1) There are suites of ecophysiological traits which lead to predictable constellations of ecosystem consequences. Due to the consistent correlations among resource-dependent processes and disturbance-dependent processes, traits which trigger changes in resource supply or disturbance have multiple, predictable consequences. 2) However, there are other plant traits that vary independently of these suites of traits, and can alter the overall plant's effect on ecosystem processes. The interaction of suites of traits with these other traits can be predictable by focusing on a functional matrix of traits, rather than simply functional groups. 3) The relative impact of different physiological traits depends on: the strength of effect (at low vs. high plant density, short term vs. long term plant presence), and the duration of the effect after the plant species has been removed. 4) Plant physiological traits vary with abiotic factors, interaction with other biota, and through time. The sensitivity of a trait to change and the corresponding change in a plant's effect on ecosystem processes varies among traits.

Keywords: physiological traits

This abstract is being presented at: 3:40 PM in session:
Symposium # 16: Plant Physiological Ecology: Linking the Organism to Scales Above and Below.