A MODEL FOR SPECIES-AREA RELATIONSHIPS IN PLANT-COMMUNITIES

A model is proposed for the fitting of species-area curves to data fro m the Stellenbosch region, South Africa. Basic assumptions of the mode l are finiteness of the number of species in a finite area, and random distribution of plant species over the region. The model involves a d istribution of densities of different species, and the parameters of t his distribution are useful for describing and classifying communities . The data of the Stellenbosch region suggest that the assumptions of the model break down in areas greater than 500 m2.