ABSTRACT
Vegetation clothes Earth and provides the vital link between the sun and Earth’s ecosystems. The fixation of the incoming solar radiation by the process of photosynthesis in the leaves and stems of plants provides the organic molecules which support all life on Earth. Without plants there would be no organisms and no human life. The distribution of plants on Earth is not random or haphazard. Plants are governed in their distribution by a range of physical and biological factors. Plants live together in communities, and so they are influenced by a range of mutual relations with other plants, just as human beings in human societies are ruled by sets of relationships. This chapter explores the nature of plant-environment relations, and the key concepts which are used in the study of vegetation communities.
