comparative assessment of gully erosion and sediment yield in different rangelands and agricultural areas in ghasr-e-shirin, kermanshah, iran

negative impacts of gully erosion in marly areas are severe due to improper landuse practices such as irrigation, tillage, overgrazing and degradation of vegetation cover. the objective of this research was to evaluate gully thresholds related to plant vegetation cover and landuse change in the agriculture (ag), fair rangeland (fr) and weak rangeland (wr) areas of ghaasr-e-shirin, kermanshah, iran in 2015. the topographical parameters and vegetation cover were measured in the field. furthermore, nine flumes were performed to determine the critical values of hydraulic parameter and sedimentation. results revealed that cross-section, width, depth and gully branches length in the fr were significantly lower than those for ag and wr (p