Wadi Kufranja catchment (126.3 km2), northern Jordan, was selected to estimate annual soil loss using the Revised Universal Soil Loss Equation (RUSLE), remote sensing (RS), and geographic information system (GIS). RUS...Wadi Kufranja catchment (126.3 km2), northern Jordan, was selected to estimate annual soil loss using the Revised Universal Soil Loss Equation (RUSLE), remote sensing (RS), and geographic information system (GIS). RUSLE factors (R, K, LS, C and P) were computed and presented by raster layers in a GIS environment, then multiplied together to predict soil erosion rates, and to generate soil erosion risk categories and soil erosion severity maps. The estimated potential average annual soil loss is 10 ton·ha-1·year-1 for the catchment, and the potential erosion rates from recognized erosion classes ranged from 0.0 to 1850 ton·ha-1·year-1. About 42.1% (5317.23 ha) of the catchment area was predicted to have moderate risk of erosion, with soil loss between 5 - 25 ton·ha-1·year-1. Risk of erosion is severe to extreme over 31.2% (3940.56 ha) of the catchment, where calculated soil loss is 25 - 50 and >50 ton·ha-1·year-1. Apart from the gentle slopes of the alluvial fan (Krayma town and surroundings), the lower and the middle reaches of the watershed suffer from severe to extreme erosion risk. High terrain, slope steepness, removal of vegetation, and poor conservation practices are the most prominent causes of soil erosion.展开更多
Socioeconomic factors and farmer’s perception of soil erosion and conservation were examined with special reference to Wadi Kufranja catchment, northern Jordan. Field data were collected through a household field sur...Socioeconomic factors and farmer’s perception of soil erosion and conservation were examined with special reference to Wadi Kufranja catchment, northern Jordan. Field data were collected through a household field survey, and soil erosion loss was calculated and mapped using the Revised Universal Soil Loss Equation (RUSLE), within a GIS/RS environment. In-situ field measurements of soil erosion were also conducted to assess splash, sheet and runoff soil erosion. The estimated potential average annual soil loss is 10 ton·ha-1 year for the watershed. 42.1% (5317. 23 ha) of the watershed area was estimated to have moderate soil loss (5 - 25 ton·ha-1·years -1). Soil erosion risk is severe to extreme over 31.2% (3940.56 ha) of the catchment, whereas the calculated soil loss is 25 - 50 and >50 ton·ha-1·year-1. The measured sheet and splash soil erosion in W. Kufranja was 10 ton·ha-1·year-1 from tillage land, and 3 ton·ha-1·year-1 from the fallow land, with an average ranges from 8 to 10 ton·ha-1·year-1. Similarly, the maximum measured soil erosion on the eastern margin of W. Kufranja was 12.7 ton·ha-1·year-1, while the minimum soil erosion was 2.9 ton·ha-1·year-1. The collected household socioeconomic/conservation data have been subjected to multivariate statistical analysis. Through factor analysis, the twenty one variables were reduced into four significant factors which account for 69.7% of the variation in the original variable. Stepwise multiple regression analysis revealed that the total variance explained by three independent variables was 0.585 (R = 0.765, R2 = 0.585). Out of the total variance, forest clearance explained 34.7%, fallow land 7.7%, and land use/land cover 16.1% respectively. The F-value for forest clearance, fallow land, and land use/land cover are significant at 0.1% level. Most of the farmers aware that poor land management, deforestation, overgrazing, traditional cultivation (cultivation up-and-down the slope, and mono-cropping), and population pressure, are the major direct and indirect causes of soil erosion. By contrast, vegetative measures (i.e., afforestation and tree planting), adoption of structural soil and water conservation measures (terraced farming, check dams and gully control), and crop system management were recommended to control soil erosion.展开更多
文摘Wadi Kufranja catchment (126.3 km2), northern Jordan, was selected to estimate annual soil loss using the Revised Universal Soil Loss Equation (RUSLE), remote sensing (RS), and geographic information system (GIS). RUSLE factors (R, K, LS, C and P) were computed and presented by raster layers in a GIS environment, then multiplied together to predict soil erosion rates, and to generate soil erosion risk categories and soil erosion severity maps. The estimated potential average annual soil loss is 10 ton·ha-1·year-1 for the catchment, and the potential erosion rates from recognized erosion classes ranged from 0.0 to 1850 ton·ha-1·year-1. About 42.1% (5317.23 ha) of the catchment area was predicted to have moderate risk of erosion, with soil loss between 5 - 25 ton·ha-1·year-1. Risk of erosion is severe to extreme over 31.2% (3940.56 ha) of the catchment, where calculated soil loss is 25 - 50 and >50 ton·ha-1·year-1. Apart from the gentle slopes of the alluvial fan (Krayma town and surroundings), the lower and the middle reaches of the watershed suffer from severe to extreme erosion risk. High terrain, slope steepness, removal of vegetation, and poor conservation practices are the most prominent causes of soil erosion.
文摘Socioeconomic factors and farmer’s perception of soil erosion and conservation were examined with special reference to Wadi Kufranja catchment, northern Jordan. Field data were collected through a household field survey, and soil erosion loss was calculated and mapped using the Revised Universal Soil Loss Equation (RUSLE), within a GIS/RS environment. In-situ field measurements of soil erosion were also conducted to assess splash, sheet and runoff soil erosion. The estimated potential average annual soil loss is 10 ton·ha-1 year for the watershed. 42.1% (5317. 23 ha) of the watershed area was estimated to have moderate soil loss (5 - 25 ton·ha-1·years -1). Soil erosion risk is severe to extreme over 31.2% (3940.56 ha) of the catchment, whereas the calculated soil loss is 25 - 50 and >50 ton·ha-1·year-1. The measured sheet and splash soil erosion in W. Kufranja was 10 ton·ha-1·year-1 from tillage land, and 3 ton·ha-1·year-1 from the fallow land, with an average ranges from 8 to 10 ton·ha-1·year-1. Similarly, the maximum measured soil erosion on the eastern margin of W. Kufranja was 12.7 ton·ha-1·year-1, while the minimum soil erosion was 2.9 ton·ha-1·year-1. The collected household socioeconomic/conservation data have been subjected to multivariate statistical analysis. Through factor analysis, the twenty one variables were reduced into four significant factors which account for 69.7% of the variation in the original variable. Stepwise multiple regression analysis revealed that the total variance explained by three independent variables was 0.585 (R = 0.765, R2 = 0.585). Out of the total variance, forest clearance explained 34.7%, fallow land 7.7%, and land use/land cover 16.1% respectively. The F-value for forest clearance, fallow land, and land use/land cover are significant at 0.1% level. Most of the farmers aware that poor land management, deforestation, overgrazing, traditional cultivation (cultivation up-and-down the slope, and mono-cropping), and population pressure, are the major direct and indirect causes of soil erosion. By contrast, vegetative measures (i.e., afforestation and tree planting), adoption of structural soil and water conservation measures (terraced farming, check dams and gully control), and crop system management were recommended to control soil erosion.
