Wu Nan, Gao Ji-xi, Ennaanay Driss, Mendoza Guillermo F, Luo Zun-lan, Li Dai-qing, Tian Mei-rong
Chengdu Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China.
Ying Yong Sheng Tai Xue Bao. 2009 Sep;20(9):2225-32.
By using software ArcGIS 9.2, an evaluation model was established to simulate the ecosystem service of Ertan Reservoir watershed in mitigating the sand sedimentation in the reservoir. In the meantime, sediment delivery ratio and universal soil loss equation were used to simulate the spatial patterns of the annual sediment yield and sediment retention in the watershed as well as the value during the service life period. In 2000, the total quantity of soil retention in the watershed was 12. 1 x 10(8) t x a(-1). The region with higher soil retention was near the main and branch streams of Yalong River, and that with higher sediment delivery ratio was near the streams and the Ertan Reservoir. The region with higher sediment yield and sediment retention was around the reservoir. The actual sediment yield in the study area was 629.3 x 10(4) t x a(-1), occupying 12.7% of the actual soil erosion volume. Farmland was the most important source of sediment yield, with its sediment yield occupying 62.9% of the total. The contribution of forestland to the mitigation of reservoir sand sedimentation was higher than that of the other lands on a per unit area basis. For the reservoir's designed operating life (100 a), the total value of the watershed in the service of mitigating Ertan Reservoir sand sedimentation was 2.75 billion yuan.
利用ArcGIS 9.2软件建立了评估模型，以模拟二滩水库流域在减轻水库泥沙淤积方面的生态系统服务功能。同时，采用输沙率和通用土壤流失方程来模拟流域年输沙量和拦沙量的空间格局以及服务期内的价值。2000年，流域内土壤保持总量为12.1×10⁸ t·a⁻¹。土壤保持量较高的区域位于雅砻江干流和支流附近，输沙率较高的区域位于溪流和二滩水库附近。产沙量和拦沙量较高的区域在水库周边。研究区域实际输沙量为629.3×10⁴ t·a⁻¹，占实际土壤侵蚀量的12.7%。农田是最重要的产沙源，其产沙量占总量的62.9%。林地在单位面积上对减轻水库泥沙淤积的贡献高于其他土地。对于水库设计运行寿命（100年），流域在服务于减轻二滩水库泥沙淤积方面的总价值为27.5亿元。
