Introduction and definitions

Abstract

At its simplest, the term community describes a group of species populations occurring together, as in a pond or woodland. However, many workers will refer to communities of birds, insects or plants for example, which causes confusion over the scale and true ecological meaning of the community. The term assemblage is a more appropriate description for such a group of similar species populations occurring together (i.e. an assemblage of birds, insects or plants). A community of organisms should be viewed more as an organized whole, and any definition should encompass interactions among constitutent populations, i.e. an association of interacting populations of all trophic levels occurring in a given habitat [1]. Species do adapt to the presence of other species, so, just as populations have properties over and above those of the individuals comprising them, the community is more than the sum of the individual populations and their interactions [2]. Whittaker’s definition [3] is the most precise to date, describing a community as a combination of plant, animal, and bacterial populations, interacting with one another within an environment, thus forming a distinctive living system with its own composition, structure, environmental relations, development and function.