The sources (ecological and biological or geological) which are essential for human life and satisfy human wants are called as resources. They fulfill the physical, economical, social and cultural needs. The sources which are obtained directly from the nature are called as Natural resources. Following are the main natural resources:
- Water resources
- Soil resources
- Wetland resources
- Energy resources
- Mineral resources
- Ocean resources
- Forest resources
Classification of Natural Resources : The natural resources are of two types:
(A) Inexhaustible Resources :
They are found with unlimited amounts in the nature. They cannot be depleted or exhausted even by their excessive use. Example: Sun energy, Wind energy, Atomic energy, Tidal energy etc.
(B) Exhaustible Resources :
They are found with limited amounts. They can be exhausted by their excessive use. They are of two types —
(a) Renewable Resources : They are the biological resources such as agriculture, forest grass land, animals etc. They can be used repeatedly because they are replaced naturally by growth or reproduction.
(b) Non-renewable Resources : They are the abiotic resources which cannot be readily replaced by natural means. Such as fossil fuels [petroleum, coke (coal), gas], mineral metals (copper, gold, silver etc). They can’t be replenished because their formation takes billions of years. They will be exhausted by their excessive use.