The influence of deforestation and anthropogenic activities on runoff generation

Abstract

In recent decades, due to rapid human population increases and in its results, destructive effects of anthropogenic activities on natural resources have become a great challenge. Land use and vegetation are important factors in soil erosion and runoff generation. This study was performed to assess the effects of different amounts of forest cover on the control of runoff and soil loss in the Talar basin, which is located in Mazandaran province, using a runoffrainfall model, geographical information system (GIS) and remote sensing (RS) to determine the hydrologic effects of deforestation on the Talar watershed (north of Iran). A runoff-rainfall model has been presented using GIS (HECGeoHMS) and hydrologic model (HEC-HMS). Land use changes (deforestation) and anthropogenic activities (roads and impervious surfaces development) were evaluated using RS techniques and satellite images. We used the Soil Conservation Service and Curve Number methods for hydrograph simulation and runoff estimation, respectively. First, a model was performed and optimized. Afterward, the optimized model was evaluated by other six events of floods (model validation). According to the obtained results, the runoff generation potential has been increased in the Talar watershed due to deforestation during the last forty years. Land use changes cause an increase in runoff volume and flood peak discharge.

Keywords

• rainfall-runoff model
• forest
• sediment
• land use
• talar watershed
• iran