Effect of Harvested Wood Management on the Sediment Production in Natural Forests

Abstract

The area under study is of 13,284 acres and of a height range between 50 and 1900 meters, located in the Khardjegil basin of Asalem (Nav Asalem) and in Asalem city, Guilan province, in the northern part of Iran . Firstly, physical factors of the area were analyzed. Then, harvested volume, as well as the harvesting method in the region was determined for the years between 1993 and 2010. The present study aims to determine the role of forest executive/operations management in the amount of sediment production, as well as to determine a factor to reduce it. Results of the study show that harvested wood has the highest effect on sediment production (R2=0.50) at a confidence level of 95% in the region. An increase in the harvesting volume and the decrease of forest surface, especially in classical forestry management methods like clear cutting method, result in the extensive loss of forest canopy cover and, in turn, the increase of sediment production