estimation of stormwise sediment yield of gully erosion using important rainfall components in different land uses of zagros forest, iran

Erosion is one of the important social-economic problems in iranian catchments that have been posed by surface water vastness and runoff production. so, the study of water resources, soil erosion and effective factors is of high importance. gully erosion also extends in many parts of iran and its study particularly in viewpoint of sediment yield is therefore very important and should be taken into account. in order to investigate the relationships between sediment yield of gully erosion and rainfall parameters such as amount, intensity and duration of them, the present study was conducted in alashtar, lorestan province, iran. for this purpose, 18 digitalized linear and frontal gullies have been identified and morphological characteristics of the gullies were specified at the beginning and after five storm runoff productions in november 2007 to may 2008. then, using matrix correlation and regression analysis, the most effective factor in the sedimentation of gully erosion was determined. the results have showed that the most important climatic factors that can be pointed out with respect to the sedimentation of gullies were the maximum and average rainfall intensities. results of regression analysis have also indicated that the maximum intensity of rainfall is the most important factor in the study area and has the ability to estimate sediment and erosion rates caused by the storms with the coefficient of determination as (r2=0.91) and the standard error value of 18.8.