There are four basic reasons for the cause of natural resources depletion. They are rapid population increase, high consumption of resources, pollution, and deterioration of land.

A rapid population increase creates resource depletion due to unbalanced amount of time between the growth of a community and a resource needed time to fulfill one?s community need. Rapid population increase comes hand in hand with high consumption resources, which has thus created resources depletions.

We are polluting atmosphere, lakes, streams, and rivers with the use of detergents, fertilizer, pesticides, and other toxic materials. The uncontrolled use of these toxic materials has disturbed the entire food chains, which animals and man are affected.

Land deteriorates gradually one of the reasons behind this is due to cropping where the cycling of soil mineral nutrients is greatly reduced. Beside that, erosion has also depleted soil fertility as most of the minerals could be easily removed by wind or water due to the minerals being in the upper part of the soil. Deteriorated agricultural land has caused the loss of national economy as well as the amount of future resources created.

Source: http://www.biologydiscussion.com/natural-resources/natural-resources-depletion-reasons-types-and-their-conservation/6992