A community with its non-king environment is called ecosystem. Odum, E.P. ( 1959) defines ecosystem as an area of nature, that includes living organism and nonliving substances, interacting to produce an exchange of materials between the living and nonliving parts. Non-living environment provides energy raw materials and space to the living organism. They use these materials for their growth and development.
Component of Ecosystem
Al) ecosystem is composed of abiotic (nonliving) and biotic (living) components:
I. Abiotic component
Abiotic component include basic elements and compounds of the environment like soil, water, gases. It is also composed of minerals like carbonates, phosphates etc. It also has variety of organic compounds. It also includes physical factors like moisture, wind, currents and solar radiation. Solar energy is the source of energy for the entire ecosystem.
2. Biotic components
The living components of the ecosystem are called biotic components. There are further divided into two main parts. i.e. Autotrophs or Producers and Heterotrophs or Consumers.
(a) Autotrophs or producers: They are able to fix light energy and manufacture food from simple inorganic substances. They mainly consist of green plants. Sonic floating microscopic photosynthetic organisms are also present They are called phytoplanktons.
Heterotrophs or Consumers: They are the living organisms that
utilize or decompose the complex material synthesized by the producers. The heterotrophs do not produce their own food. They depend on other autotrophic organisms for their nourishment. The heterotrophic component includes macroconsumers and microconsumers or decomposers. Macroconsumers include large animals. It is further divided into:
- Primary consumers: They are purely herbivorous animals.
They include large animals or macroconsumers like many insects, mouse, rabbits, goat sheep. deer, birds etc. These are the common herbivorous of terrestrial ecosystem. Protozoa small molluscs and Crustaceans and fishes are herbivores of the aquatic ecosystem. It includes rotifers, protozoans and crustaceans. They live only on phytoplankton or microscopic plants.