Ecosystem - Definition

An ecosystem can be defined as 'a structural and functional unit of biosphere or segment of nature consisting of community of living beings and the physical environment, both interacting and exchanging materials between them'.

• E. P. Odum, an American ecologist, defined ecology as, 'the study of the structure and function of nature, which includes the living world'. He referred ecosystem as the basic fundamental unit of ecology

• Charles Elton, a British ecologist, defines ecology as, 'the study of scientific natural history'

• Andrewartha, an Australian ecologist, defined ecology as, 'the study concerned with the distribution of organisms'

• According to S. Mathavan, 'an ecosystem is a sum total of living organisms, the environment and the process of interaction between the various components of the ecosystem'

Besides a mechanical system or a living body, the ecosystem usually has a boundary within which the component parts function together as one unit.

An ecosystem may be natural (like forest, lake, ocean etc) or man-made (such as an aquarium, a crop field etc), temporary (like a rainfed pond) or permanent (like a lake, forest, etc), aquatic (such as pond, ocean etc) or terrestrial (like grassland, forest, etc).

Classification of Ecosystem

An ecosystem may be as small as a drop of pond water and as large as an ocean. Ecosystems can be recognised as self - regulating and self - sustaining units.