ECOSYSTEM - COMPONENTS OF AN ECOSYSTEM, BIOTIC AND ABIOTIC COMPONENTS

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            Ecosystem may be defined as a natural, functional, ecological unit comprising living organisms and their non living environment that interact to form stable, self supporting system.
            COMPONENTS OF AN ECOSYSTEM
            Components of an ecosystem can be classified into two major divisions – Biotic and Abiotic components.
            1. Biotic Components:- All living organisms present in the environment are included within the biotic component. The biotic components can be sub divided into three major groups –
            a) Producers – These includes all the autotrophic green plants which can make their own food with the help of sunlight. Besides these some organisms like Cyano-bacteria and some Chemo-systhetic bacteria can produce their own food, which are also included in producers.
            b) Consumers – These includes all heterotrophic organisms which depend on plants and other organisms for food and nutrition. Based on the food they eat, consumers are again sub-divided into three groups – Herbivores (Plant eaters; e.g., – Rabbit, deer, cow, goat, etc.), Carnivores (Meat eaters; e.g., – Tiger, lion, fox, etc.) and Omnivores (Both plant and meat eaters; e.g., – Man, bear, etc.)
            c) Decomposers – These are mainly bacteria and fungi that obtain their food form organic materials of dead plants and animals and decompose the complex organic molecules into simpler ones which can be readily used up by green plants again.
            2. Abiotic Components:- The non-living matters constitute the abiotic components of an ecosystem. It includes physical and chemical components like climatic factors, edaphic (soil) factors, geographical factors, energy, nutrients and toxic substances.
            a) Physical factors:- The sunlight and shade, intensity of solar flux, duration of light hours, average temperature, annual rainfall, wind, latitude and altitude, soil type, water availability, water currents, etc., are some of the important physical features which have a strong influence on the ecosystem.
            b) Chemical factors:- Availability of major nutrients like carbon, nitrogen, phosphorous, potassium, hydrogen, oxygen and sulphur, level of toxic substances, salts causing salinity and various organic substances present in the soil or water largely influence the functioning of the ecosystem.
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