Read the passage and choose the appropriate title.
In the Himalayas people cut down forests simply because there are a lot of people who need firewood to keep warm. And so they cut down huge hillsides. This leaves fertile Himalayan hills naked, unprotected from the heavy rains. The trees were umbrellas, and now the rain washes out the good soil, which ends up as mud a thousand miles away in the channels of the river Ganges.