基于水系改进的高分辨率DEM和GEOWEPP,从坡面、子流域和流域3种空间尺度对五桥河流域产沙量进行了估算。结果表明,从不同的空间尺度进行考察,流域的水土流失特征存在较大的差异。从坡面尺度到子流域尺度和流域尺度,研究区114.6 km2面积...基于水系改进的高分辨率DEM和GEOWEPP,从坡面、子流域和流域3种空间尺度对五桥河流域产沙量进行了估算。结果表明,从不同的空间尺度进行考察,流域的水土流失特征存在较大的差异。从坡面尺度到子流域尺度和流域尺度,研究区114.6 km2面积上的年产沙总量从3.79×105t减少至1.25×105t和0.84×105t,单位面积年产沙量从33.09 t hm-2减少至10.94 t hm-2和7.29 t hm-2,年均泥沙输移比从1.000减小至0.331和0.220。将GIS与GEOWEPP结合,既能反映流域输出终端的泥沙量,又可以刻画流域内部土壤侵蚀的强度和空间分布,能为流域水土保持措施布置提供更为科学的依据。展开更多
The large-scale management of ditches and implementation of land projects in loess areas have increased the arable land area but have caused considerable engineering issues, resulting in severe soil erosion. In this s...The large-scale management of ditches and implementation of land projects in loess areas have increased the arable land area but have caused considerable engineering issues, resulting in severe soil erosion. In this study, field tests were performed at different time scales, a control group was established, organic material–plant joint restoration technology was proposed as an optimized management measure, and the erosion control mechanism and restoration mode of organic material–plant joint restoration technology were analyzed. Based on the obtained experimental data, a Water Erosion Prediction Project(WEPP)-based hydraulic erosion model was constructed, sensitivity parameters were calibrated, and the soil erosion intensity and corresponding spatial distribution in the watershed of the study area were simulated via the geo-spatial interface for WEPP(GeoWEPP) after organic material–plant joint restoration technology was adopted to predict the effect of optimized management measures. The results showed that among the slopes with different restoration measures, organic material–plant joint restoration technology effectively controlled loess slope erosion, and the average erosion modulus of the organic material–grass and shrub transplantation slope reached only 23.37 t/km^(2), which is a decrease of 97.68% relative to the traditional grass–shrub protection slope. Moreover, the sand content of the joint restoration slope was reduced by 392.41 g/L relative to the bare slope, reaching only 0.29 g/L, and the runoff yield was reduced by 8.88 L/min. The GeoWEPP modeling results revealed that the total runoff yield and average annual erosion modulus of the watershed were lower after joint restoration than during the prerestoration period. Similarly, the total runoff yield of the watershed was 4.6%, the simulated 10-year average annual total sand production reached 2048.3 t,and the average annual erosion modulus was 582.75 t/km^(2), which is 52.15% lower than that under untreated conditions. This study provides a new strategy for solving soil erosion problems and restoring the ecology of slopes after managing ditches and implementing land projects.展开更多
文摘基于水系改进的高分辨率DEM和GEOWEPP,从坡面、子流域和流域3种空间尺度对五桥河流域产沙量进行了估算。结果表明,从不同的空间尺度进行考察,流域的水土流失特征存在较大的差异。从坡面尺度到子流域尺度和流域尺度,研究区114.6 km2面积上的年产沙总量从3.79×105t减少至1.25×105t和0.84×105t,单位面积年产沙量从33.09 t hm-2减少至10.94 t hm-2和7.29 t hm-2,年均泥沙输移比从1.000减小至0.331和0.220。将GIS与GEOWEPP结合,既能反映流域输出终端的泥沙量,又可以刻画流域内部土壤侵蚀的强度和空间分布,能为流域水土保持措施布置提供更为科学的依据。
基金National Natural Science Foundation of China,No.42107179, No.41702335The State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Independent Research Project,No.SKLGP2021Z021, No.SKLGP2022Z005。
文摘The large-scale management of ditches and implementation of land projects in loess areas have increased the arable land area but have caused considerable engineering issues, resulting in severe soil erosion. In this study, field tests were performed at different time scales, a control group was established, organic material–plant joint restoration technology was proposed as an optimized management measure, and the erosion control mechanism and restoration mode of organic material–plant joint restoration technology were analyzed. Based on the obtained experimental data, a Water Erosion Prediction Project(WEPP)-based hydraulic erosion model was constructed, sensitivity parameters were calibrated, and the soil erosion intensity and corresponding spatial distribution in the watershed of the study area were simulated via the geo-spatial interface for WEPP(GeoWEPP) after organic material–plant joint restoration technology was adopted to predict the effect of optimized management measures. The results showed that among the slopes with different restoration measures, organic material–plant joint restoration technology effectively controlled loess slope erosion, and the average erosion modulus of the organic material–grass and shrub transplantation slope reached only 23.37 t/km^(2), which is a decrease of 97.68% relative to the traditional grass–shrub protection slope. Moreover, the sand content of the joint restoration slope was reduced by 392.41 g/L relative to the bare slope, reaching only 0.29 g/L, and the runoff yield was reduced by 8.88 L/min. The GeoWEPP modeling results revealed that the total runoff yield and average annual erosion modulus of the watershed were lower after joint restoration than during the prerestoration period. Similarly, the total runoff yield of the watershed was 4.6%, the simulated 10-year average annual total sand production reached 2048.3 t,and the average annual erosion modulus was 582.75 t/km^(2), which is 52.15% lower than that under untreated conditions. This study provides a new strategy for solving soil erosion problems and restoring the ecology of slopes after managing ditches and implementing land projects.
