College of Water Conservancy, Shenyang Agricultural University, Shenyang 100866, China.
Key Laboratory of Soil Erosion Control and Ecological Restoration in Liaoning Province, Shenyang 100866, China.
Ying Yong Sheng Tai Xue Bao. 2023 Mar;34(3):726-732. doi: 10.13287/j.1001-9332.202303.036.
Understanding the spatial distribution characteristics of soil erosion and sediment connectivity is important for formulating integrated watershed management measures. Based on the InVEST sediment delivery ratio model, we used the connectivity index and soil loss model to measure the spatial distribution characteristics of sediment connectivity and soil erosion in Erdaoling watershed of brown soil hilly region of low mountains in western Liaoning. By exploring slope, aspect and land use characteristics under different sediment connectivity levels and soil erosion levels, we analyzed the relationships among topography, land use, sediment connectivity, and soil erosion. The results showed that the average sediment connectivity in the watershed was -3.79, and that the average soil erosion was 614 t·km·a. High connectivity was mainly found in sloping farmland, while low connectivity was mainly found in forest and grassland. The soil erosion intensity of 93.3% of the watershed area was below moderate, with only 1.1% of the area being above extremely strong. The higher the sediment connectivity level, the higher the proportion of the area <5° slope, while the area proportion of the rest slope was relatively stable. The proportion of cultivated land area increased, while the proportion of forest and grassland land area decreased. The area proportion on negative slope decreased, while that on positive slope increased. With increasing soil erosion intensity, the area proportion of slope <8° increased and the area proportion of the rest slope was relatively stable. The proportion of forest and grassland area decreased, while the proportion of other land use area increased. The proportion of slope area on positive slope increased, while that on negative slope decreased. Land use was a key factor influencing the spatial response relationship between soil erosion and sediment connectivity in this watershed.
理解土壤侵蚀和泥沙连通性的空间分布特征对于制定综合流域管理措施非常重要。本研究基于 InVEST 泥沙输送比模型，采用连通指数和土壤流失模型，测算辽西低山丘陵褐土区二道岭流域泥沙连通性和土壤侵蚀的空间分布特征，通过探讨不同泥沙连通性和土壤侵蚀水平下的坡度、坡向和土地利用特征，分析地形、土地利用、泥沙连通性与土壤侵蚀之间的关系。结果表明：流域平均泥沙连通性为-3.79，平均土壤侵蚀模数为 614 t·km·a。高连通性主要分布在坡耕地，低连通性主要分布在林地和草地。流域 93.3%的区域土壤侵蚀强度处于中度以下，仅有 1.1%的区域土壤侵蚀强度处于极强以上。泥沙连通性水平越高，<5°坡度的面积比例越大，其余坡度的面积比例相对稳定。耕地面积比例增加，林地和草地面积比例减少。负坡面积比例减少，正坡面积比例增加。随着土壤侵蚀强度的增加，<8°坡度的面积比例增加，其余坡度的面积比例相对稳定。林地和草地面积比例减少，其他土地利用类型面积比例增加。正坡面积比例增加，负坡面积比例减少。土地利用是影响该流域土壤侵蚀与泥沙连通性空间响应关系的关键因素。
