water resources are divisible into two distinct categories : the surface-water resources & the ground-water resources. Each of these categories is a part of the earth's water circulatory system,called the hydrologic cycle, & is ultimately derived from precipitation,which is rainfall plus snow. They are interdependent & frequently the loss of one is the gain of the other. The brief description of the run-off cycle,which is a part of the hydrologic cycle,will help us to understand the origin & the interdependence of these two categories of water resources.
97% of water on the Earth is salt water, leaving only 3% as fresh water of which slightly over two thirds is frozen in glaciers and polar ice caps.[1] The remaining unfrozen freshwater is mainly found as groundwater, with only a small fraction present above ground or in the air.
Sourecs of fress water.
- surface water.
- under river flow.
- ground water.
- desalination.
- froozen water.
- agricultural
- industrial.
- household.
- recreation.
- environmental
- population growth.
- expansion of business activity.
- climate change.
- water & conflict.
- polution & water protection.
- rapid urbanization.
- deplation of aquifers.
No comments:
Post a Comment