Analysis and Prediction of Population and Community Change: A Grassland Case Study

Abstract

The mechanisms of successional change were analysed in a mediterranean coastal grassland undergoing post-grazing succession at Sea Ranch, northern California, U.S.A. The study included field experiments and observations on the five most abundant species, including four perennial grasses and one annual grass. The results explain the observed trends in the populations, and allow prediction of future change. Patchiness in species distributions, dispersal ability, and localised disturbances strongly affected the outcomes of species interactions. Competitive ability was found to have two distinct components, inhibition and invasion, which were not well correlated. Overall, the analyses show that it is possible to link population and community ecology effectively using appropriate field methods, at least in simple communities.