What is Eco-system?
An assemblage of species of plants and animals inhabiting a common area and having effects on one another is known as a biotic community. A combination of a biotic community with the natural or physical environment is known as an ecosystem. The term eco-system implies to a local community of organisms inter-acting with their local non-living environment. In other words the interdependence of living and non-living aspects i.e. plants, animals, man, forest, soil etc. make an eco-system. It is defined as an unit which include all the organisms (biological component) in a given area inter-acting with the environment (physical component) so that the flow of energy leads to a clearly defined tropic (nutrient supply) structure biotic diversity and material cycles.
It means every eco-system has a flow of energy and cycling of nutrients which bind the biological and physical components together. Every eco-system has a certain capacity to sustained – its components without deterioration this is called its carrying capacity. An ecosystem does not remain constant. Changes occur in it continuously in one form or the other. It is significant that even a small change in one part of an ecosystem is felt though out the eco-system. This establishes the importance of inter-linkages in an eco-system. However the system tries to maintain the stability of an eco-system depends on its diversity. More the diversity more is the inter dependence and more is the resistance to change.
This does not however mean that ecosystem is devoid of any change. Changes do occur. It is the drastic change in eco-system that affects the environment. An eco-system has two important aspects namely structure and function. The structure includes the composition quantity and distribution of the biological and physical components. The function includes aspects such as rate of energy flow and nutrients, ecological regulation of environment by the organism etc. Some of the major eco-system of the world are sea’s, fresh water marshes streams, rivers, lakes, ponds, deserts grasslands and forest. Broadly speaking ecosystem can be divided into two major categories:-
1) Aquatic or water eco-system such as seas, rivers, ponds etc.
2) Terrestrial or land eco-system such as deserts, forests etc. Eco-system constitutes a very important unit of environment. It consist of three main components namely producers, consumers, decomposers and reducers. Producers – they basically include plants which act on self-nourishing organism. These plants contain chlorophyll and with its help, they obtain solar energy and manufacture it into food, they act on a starting point in a good chain all living organisms depend on the existence of producers for their requirements of food, thus they are primary source of energy. Consumer – they are mainly of two types namely the macro consumers and micro Consumers. The macro consumers can be further divided into 3 types as follows
(a) primary consumer, they include the herbivorous or grass eating animals which feed on green vegetation for ex-sheep deer etc.
b) Secondary consumers – they include the carnivorous which eat the flesh of herbivorous they are also called as herbivorous predators for ex fox, hyenc on land and fish and crabs in water.
c) Tertiary consumers – they include the animals which feed on secondary consumers and are known as higher level carnivores ex-tiger lion on land and sharks in water a part from these omnivores are also included that this organism which depend both on primary and secondary for e.g. Man. The Micro consumer are called as deterivores such as earthworms, centipedes etc. they feed on organic matter.
3) Decomposers and reducers – they include the bacteria and fungi. These are basically micro scop organism. They break down complex compounds of dead plants and animals absorb some of the decomposed products and release mineral nutrients into the soil.
Bacterial decomposed dead animal tissues and fungi decompose dead plants tissues. In this process of decomposition and reduction the nutrients which are released into the soil are used by procedures.