بررسي مهمترين عوامل تأثيرگذار بر فرآيند فرسايش خاك در مراتع نيمه خشك كلات

Investigation of the most Important Factors Affecting on Soil Erosion in Kalat Semi-Arid Rangelands

Abstract Soil erosion is a hazard associated with agriculture in tropical and semi-arid areas and is important for its long-term effect on soil productivity and sustainable agriculture. Erosion also leads to environmental damage through sedimentation, pollution and increased flooding. This research has been performed in order to assessment and determination of soil resistance or weakness against erosion and also determination of effective factors in this process. Measurements have been accomplished in experimental plots outfitted with runoff and sedimentation reservoirs that located in semi-arid rangeland fields at northeastern Khorasan Razavi province. In this study, many of physical and chemical soil properties, vegetative cover density percentage and slope of the field was measured and finally the relationship between these factors and the amount of eroded soil due to 43 events of erosive rainfall was studied by statistical softwares. The linear multiple regression indicated that three factors of vegetative cover density percentage, percentage of coarse gravel (13-75 mm) in surface layer of soil and slope percentage of the field are the most important factors affecting on soil erosion, respectively. Therefore, management of vegetative cover and slope of the studied rangeland fields are the first steps to reduce the potential of soil erosion. Keywords: Soil erosion, Experimental plots, Semi-arid rangeland, Vegetative cover, Gravel