Environment Meaning,Defination and Components.
Environment that surrounds us and affects living organisms is environment. It is derived from the french word environner ,which means to encircle or surround. All the biological and non bio logical entities surrounding us are included in it.
1. According to Environment Protection Act ,1986,”The sum total of water ,air and land and the inter relationships that exists among them and with the human beings,other living organisms and materials.”
2.Declaration of UN Conference on human Environment,Stockholm 1972, defined environment as comprising of air,land and water especially representative sample of natural ecosysytems.
3. According to E.J.Ross”Environment is an external force which influences us.”
4.According to P. Gisbert “Environment is anything immediately surrounding an object and exerting a direct influence on us”
Components of Environment.
It provides all the things necessary to nourish life in all its varied forms like air, water ,land ,food ,shelter and so on . There are four spheres that makes up the environment lithosphere, hydrosphere, atmosphere,and biosphere,which correspond to rocks,water,air, and life respectively.
“Lithos” is a Greek word for rock and and “sphere”refers to the region or realm where rocks and rock-like structures are available. It is the outermost layer of the Earth called crust. Below the crust lies the mantle,which extends till the core of the earth. The uppermost layer of the Earth along with tge crust forms a part of lithosphere.
“Hydro” is a Greek word for water and the word “sphere” refers to the zones on earth where water is found in all forms, under and inside the planet falls under the hydrosphere. It includes the oceans,seas,lakes,ponds,rivers,and streams. The hydrosphere covers about 70% of the surface of the earth. 97.5% found in oceans,only 2.5% of water on earth is freshwater.
The word “atmos” is a Greek word for vapour or gases;hence,the word atmosphere refers to the gaseous layer enveloping the earth. The atmosphere is unique to planet Earth and sustains life. It is like a blanket enveloping the earth and is held in place by the surface gravity. The composition of the various gases in thw atmosphere is as fallow:78.08%nitrogen,20.95% oxygen,0.93%argon,0.038%carbon dioxide.
“Bio” is a greek word for life;hence,the word biosphere refers to all the regions on earth where life exists. The ecosystem that support life could be in soil,air,water and land. Biosphere refers to the sum total of all living matter,the biomass or biota.