ABSTRACT
The species of plants and animals present in a given area constitute its flora and fauna. The relative abundance and distribution of plant life forms determine the structure of the biomass. All organisms live in company with a greater or lesser number of others of the same or different species populations and together form a biomass or standing crop. During the course of evolution the species which have become dominant are those with a form that has best fitted them to compete successfully under the prevailing climate. A community distinguished by dominance of a particular growth form or combination of growth forms is called a plant formation—in general terms ‘a type of vegetation’. Empirical studies, particularly of plant diversity, indicate that under similar environmental conditions nutrient-deficient and disturbed habitats are often characterised by species richness rather than poverty. Stratification or vertical distribution of the component life forms is the most obvious structural characteristic in both terrestrial and aquatic plant biomass.
