Man has been living on this earth for many thousands of years.
He is surrounded by various life forms, forces and conditions- both physical and biological. Sunlight, land, air and water form physical conditions whereas all the plants, animals, and microorganisms form biological conditions.
Both the physical and biological conditions that surround us spontaneously are called natural conditions. These conditions together constitute our Natural Environment.
Besides natural conditions there are man-made conditions also. All the man-made conditions inside the natural conditions constitute the man-made environment or the Social environment.
The pattern of complete range of organisms and external conditions that surround us is called as Environment.
Different types of plants and animals are found around us. They all survive by using air, water, sunlight, soil etc. found around them. They all face the environmental changes and try to adapt and survive under them. They all have to take food, oxygen etc. and to maintain their population in particular areas.
All the living beings live in different groups and every group of organisms has its own lifestyle, feeding habits, modes of reproduction etc.
Environment has been composed of two types of components- biotic components and abiotic components.
All the plants and animals and microorganisms constitute biotic components whereas soils, minerals, air, rocks etc. are abiotic components of environment.
Both the biotic and abiotic components of environment depend on each other with a continuous interaction. In the whole environment food and mineral substances along with water run into a continuous cycle called as Bio-geo-chemical cycle.