Investigation of vegetation in river bank stabilization, soil erosion and sediment production in Pesikhan watershed (Gilan)

In this paper, a bioengineering method for biological stabilization of riverbanks in Gilan region is reviewed and the most appropriate biological method is introduced in terms of plant density and composition. First, using hydraulic information and models such as HEC-RAS, the boundary flow hydraulic conditions and shear stress are evaluated. Vegetation in the form of 5 predicted units including: tree, shrub, shrub, combination of tree and shrub and control, was carried out along the river. Each treatment had 3 replications. In each treatment and its repetitions, from the level of dehydration to the upper edge of the walls, pins perpendicular to the current were hammered. Statistical analysis in this study was performed as a factorial experiment in a completely randomized design. Data analysis was performed using SPSS software. To compare the treatments, Duncan test and significance level were P≥0.05. In this study, in the years of statistics and also statistical analysis showed that the grass cover in the surface has little erosion, this does not indicate that the presence of grass cover has been able to have good protection against erosion. And the vegetation of the tree is more exposed to water flow. For this reason, in the recorded statistics, erosion shows a high number, but during the occurrence of severe floods that cause floods, it was observed in the statistical period that it was observed. . In tree and shrub cover, the walls have maintained their stability. Mechanical and engineering is essential.