An Ecosystem includes all of the living things (plants, animals and organisms) in a given area, interacting with each other, and also with their non-living environments (Weather, Earth, Sun, Soil, Climate, Atmosphere).
The study of Ecosystems mainly consists of the study of certain processes that link the living, or Biotic, components to the non-living, or Abiotic, components. Energy transformations and biogeochemical cycling are the main processes that comprise the field of ecosystem ecology. As we learned earlier, ecology generally is defined as the interactions of organisms with one another and with the environment in which they occur. We can study ecology at the level of the individual, the population, the community, and the Ecosystem.
We can clarify the parts of an ecosystem by listing them under the headings "Abiotic" and "Biotic".
Usually, biological communities comprise the "functional groupings" shown above. A functional group is a biological category composed of organisms that perform mostly the same kind of function in the system; for example, all the photosynthetic plants or primary producers form a functional group. Membership in the functional group does not depend very much on who the actual players (species) happen to be, only on what function they perform in the Ecosystem.
Structure of the Ecosystem:
Producer, Consumer and Decomposers:
Every living organism is in some way dependent on other organisms. Plants are food for herbivorous animals which are in turn food for carnivorous animals. Thus there are different tropic levels in the ecosystem.
Plants are the ‘Producers’ in the ecosystem as they manufacture their food by using energy from the sun. In the forest these form communities of plant life. In the sea these include tiny algal forms to large seaweed.
The Herbivores animals are primary consumers as they live on the producers. In a forest, these are the insects, Amphibia, Reptiles, Birds and Mammals. The herbivorous animals include for example hare, deer and elephants that live on plant life. In grasslands, there are herbivores such as the blackbuck that feed on grass. In the semi-arid areas, there are species such as the Chinkara or Indian gazelle.
At a higher tropic level, there are carnivorous animals, or secondary consumers, which live on herbivorous animals. In our forests, the carnivorous animals are tigers, leopards, jackals, foxes and small wild cats.
Decomposers or Detritivores are a Group of Organisms consist of small animals like worms, insects, bacteria and fungi, which break down dead organic material into smaller particles and finally into simpler substances that are used by plants as nutrition. Decomposition thus is a vital function in nature, as without this, all the nutrients would be tied up in dead matter and no new life could be produced.