- The organisms found in the biosphere are broadly divided into plant kingdom and animal kingdom.
- The four realms of the earth interact with one another and affect one another in some way or the other.
The growth of human population is a major cause of change in the biosphere. The growing population requires space for living. This leads to increase of silt in rivers that results ultimately into floods.
- Floods provide new soil or alluvial (sand and earth).
- But simultaneously floods destroy human habitation and cause complete disruption in smooth living of people.