In an ecosystem, living organisms interact among themselves and also with the surroundings continuously and yet maintain a balance. Ecosystem is divided into two basic categories namely terrestrial and aquatic.
Humans can also make ecosystems. For example, aquarium, gardens and agricultural fields are examples of man-made ecosystem.
The various components of an ecosystem function as a complete unit and have definite relationships with each other. The living organisms are directly or indirectly dependent on each other and use various natural resources for their survival. However, because of the growing human population there is a tremendous pressure on natural resources. The need of the hour, thus, is to check the overuse of our natural resources.
Ecosystem = Non-living Component (Abiotic) + Living Component (Biotic)
All components of a biotic community are connected through food and energy available. They also form a web of inter-relationships.
A number of controlled processes occur in an ecosystem. Plants use nutrients from the soil. Their availability is largely dependent upon decomposition and mineralization of organic detritus. Animals found in an ecosystem are delicately balanced by the number of herbivores and the degree to which they are being eaten.
Nutrients like carbon, nitrogen, water, sulphur and phosphorus are present in definite amounts in the ecosystem.
Saprophytes help in recycling the nutrients back into the atmosphere by feeding on the dead and decaying organic matter and in the process also help in cleaning the environment.
Energy flow is unidirectional. Only part of the energy is transferred to the next trophic level.
The three important functions of an ecosystem are:
- Productivity and energy flow
- Nutrient cycling
- Development and stabilization
When two species use the same resource at the same time, the result is Competition and neither species does as well as it would in the absence of the other species.
Mutualism is a relationship between two different species which benefits both species. Commensalism is when a species benefits by living in or on another species but has no effect on its host.
A close interaction between two or more different organisms of different species living in close physical association is symbiosis.