COMPETITION AND COEXISTENCE IN PLANT-COMMUNITIES

Few ecologists today doubt that competition is an important structurin g factor in plant communities, but researchers disagree on the circums tances where it is most intense, and on which traits can be considered to contribute to competitive ability in different species. The distin ction between a species' effect on resources and its response to reduc ed resource levels might help to solve these questions. Whereas classi cal competition theory predicts competitive exclusion of species with similar requirements, recent ideas stress that species diversity may b e explained by a multitude of processes acting at different scales, an d that similarities in competitive abilities often may facilitate coex istence.