Covering ideas on the nature and causes of temporal change in the species composition of vegetation, this book examines in particular the diverse processes of interaction of plants with their environment and with one another, through which the species composition of vegetation becomes established. Areas covered range from the tropics to sub-polar regions and from sea shores, through deserts, grasslands and forests to alpine regions. The text focuses on the nature of reciprocal interaction between plants and their habitats and other organisms ; outlines events that occur during the colonization of new sites and consequent modifications of habitat; explores long-term consequences of change, using chrono-sequences and fossil data from wetland sites; and considers cyclical replacement sequences, direct replacements and fluctuations in the context of short-term and long-term change.