Study on the effect of forest, afforested and disturbed forest using natural rainfall on infiltration, runoff and sediment in Shastkalate watershed, Golestan Province

Presently, evaluation of soil erosion and sediment yield is one of the challenging issues in watershed management. It is considered to be a concerning issue in the developing countries and thus access to accurate data is essential for the measurement of soil erosion and sediment in watersheds for proper designing of soil conservation programs and determine ways to against erosion and reduce sediment. The natural resources degradation and soil erosion are the major problems in Golestan Province. The aim of this study was the investigation of sediment and runoff in experimental plots by using of natural rainfall in three land uses of forest, afforested and disturbed forest in Shastkalate watershed.
Nine erosion experimental plots with 2×2 (m) size were installed in all three land uses.
The results showed that in 1.7 to 14.4 (mm) of precipitation, the amount of sediment were 0.007 to 19.95 (g) in natural forest, 0.13 to 11.87 (g) in afforested and 0.26 to 43.94 (g) in disturbed forest land uses. The amount of runoff varied from 0.23 to 25(l) in forest, 0.1 to 16.1 (l) in afforested and 0.27 to 25 (l) in disturbed forest land uses.
Results showed that the forest degradation increased erosion and runoff at rate of 63.4 and 32%, respectively. Whilst, the amount of erosion and runoff decreased in afforested land use by 46.6 and 50.7%.