摘要 : This study aims at quantifying soil losses in an agricultural catchment site of 5,2 hectares, located upstream the Nakhla watershed. The evolution of linear erosion both vertically and horizontally was observed by means of a topog... 展开 This study aims at quantifying soil losses in an agricultural catchment site of 5,2 hectares, located upstream the Nakhla watershed. The evolution of linear erosion both vertically and horizontally was observed by means of a topographic survey. The results of this monitoring show that soil losses reached 187 tons, that is approximately 36 tons per hectare for the period between 28/11/1997 and 19/05/1998 during which a rainfall of 656 mm was recorded. The study of the factors affecting gully development, especially those related to topography and soil structure, shows that in upslope fallow fields, slopes of 20 percent ana more dominantly affect gully activity. The structural stability of these soils developed on marly material is the factor that explains most of soil losses through gullying (R~2=0.50). 收起