Environment is whatever we see in our surroundings. The word ‘environment’ is derived from a French word Environer or Environner, which means ‘neighbourhood’. All natural and man-made things present around us, are a part of our environment. It is our basic life support system and consists of both living and non-living things. Environment provides us many things. It provides us with:
Air to breathe
Food to eat
Land to live, and
Water to drink
There are three components of environment:
Human Environment, and
Natural environment has four domains:
Lithosphere: Solid portion of the earth on which we live
Hydrosphere: Refers to the domain of water
Atmosphere: Consists of gaseous layers that surround the earth
Biosphere: Comprises of the living organisms
Also, natural environment is composed of:
1. Biotic Environment, and
2. Abiotic Environment
Biotic Environment is the world of living organisms, in which the organisms interact with each other and their abiotic environment. Ex: Plants and animals.
Abiotic Environment comprises of the non-living part existing in the environment. It includes all the elements that are necessary for the existence of an organism. Ex: solar energy, weather, climate, soil and water. Biotic environment is dependent on abiotic environment.
Atmosphere is divided into five layers:
The density of atmosphere varies with height. It is maximum at the sea level and decreases rapidly as we go up.
When all the biotic and abiotic components of a particular area form relationships among themselves in a sustainable way, they form an ecosystem. Ecosystem can be as big as a forest or as small as a tree.