Ground water will not be depleted due to

Although coal and petroleum are produced by the degradation of biomass,we still need to conserve them. Why?

What is water harvesting? How can this technique help in the conservation of water?

In our country,there are attempts to increase the height of several existing dams like Tehri and Almati,dams across Narmada. Choose the correct statements among the following that are a consequence of raising the height of dams:
$(i)$ Terrestrial flora and fauna of the area is destroyed completely.
$(ii)$ Dislocation of people and domestic animals living in the area.
$(iii)$ Valuable agricultural land may be permanently lost.
$(iv)$ It will generate permanent employment for people.

Large-scale deforestation decreases $......$

Mention the action taken by the Government to save the river Ganga.