21-Effect of afforestation on runoff from a forested mountainous catchment.

Abstract

The effect of afforestation on runoff has been studied and discussed for many years but till todate there is no single index to quantify the effect of Gradually varying forest cover for prediction of yield for management of water resources in our country because of variable response of forested watersheds. To, study the effect of afforestation on runoff a study was conducted in a lower Himalayan forested catchment where afforestation and other soil conservation measures are in progress. The analysis by flow duration curve for pretreatment and post treatment period reveals decreasing trend in flow regime by 22.4$. The peak flows have decreased by 18.1$ with minor increases in mean and low fluws (1.3 and 0. 3 respectively). The decrease in peak runoff has been further confirmed by analysing the rainfall runoff events for the same period by statistical analysis which registered a decrease in runoff volume by 12.43%.