Document: AXE-3-82-13

Modelling climatic constraints of the diversity of plant species and lifeforms.

KLEIDON, A.* and H.AMOONEY

Stanford University, Stanford, CA 94305 USA ¹

Abstract:
How and how much do climatic aspects affect the diversity of plant species? We approached this question from a process-based perspective by developing a simulation model of a generic plant. Individual growth strategies of different plant species were defined by unique sets of model parameters related to allocation and phenology. A large number of different growth strategies were tested in different climatic regions for "success", that is the ability of the plant to reproduce during its lifetime. The resulting global map of functional plant species diversity compares very well with observations, reproducing the majority of biodiversity hotspots as well as the latitudinal gradient in species diversity. The major cause for the computed pattern is the variability of moisture and heat availability during the plant's establishment, which is linked to variability in precipitation and temperature. The more frequent dry or cold periods are, the more constrained the possible growth strategies. Analysis of the simulated plant properties reveal five distinct lifeforms, ranging from short-lived, fast growing plants to long-lived, slow-growing plants, similar to grasses and trees. These results suggest that constraints imposed by the physical environment may be a dominant force in shaping the global pattern of species diversity.

Keywords: biodiversity, climate, modeling

This abstract is being presented at: 3:30 PM in session:
CLIMATE CHANGE