¥61.9%
of watershed land area in 2003 ¥Up from 59.5% in 1965
The forested areas in the
watershed help to absorb nutrients into the ground water and can lessen or
prevent runoff and erosion.The
roots of trees and shrubs take up water and nutrients for their own use, while
binding the soil in place so that excess nutrients are not carried into the
lake when it rains.Forests
with extensive canopies prevent some of the rainwater from reaching the
ground, and diminish the amount of water that needs to be absorbed into the
soil and roots.The canopy also
weakens the force with which the rain strikes the soil, causing less erosion
There was an increase in
forest cover from 1965 to 2003, which was probably because much of the
reverting land had time to grow into mature forest.This increase is a favorable change
because in a mature forest there are more roots to take up nutrients and to
prevent runoff and erosion.