State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an 710048, China.
College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China.
Sci Total Environ. 2019 May 10;664:984-994. doi: 10.1016/j.scitotenv.2019.01.430. Epub 2019 Feb 7.
Revegetation and check dam construction are two widely applied soil erosion control measures on the Loess Plateau of China. They play important roles in sediment yield reduction. However, it remains unclear how these large-scale land-use changes and in-channel structures affect water yield and sediment load on the watershed scale. A combination of field work and modeling exercises were used to quantitatively assess the effects of land-use changes and check dam construction on hydrological processes in the Wuding River watershed. The study area suffered important land-use changes with increases in forestland and grassland, coupled with decreases in cropland, from 1980 to 2010. A large number of check dams were constructed from 1970 to 1980. Runoff and sediment yield in the watershed showed significant decreasing trends (P < 0.01), with change points occurring in the early 1970s. Human activity contributed to 75% and 89% of runoff and sediment changes, respectively. The simulations showed that in a scenario without check dams, runoff and sediment increased by 12% and 11.7%, respectively. Vegetation recovery reduced runoff and sediment yield. 'Grain for Green' resulted in decreasing runoff and sediment levels, and reforestation had more hydrological regulatory effects compared with scenarios involving the conversion of cropland to grassland. Moreover, the combination of revegetation and check dam construction had a greater impact on water yield and sediment transportation. Check dams provide short-term flood control and sediment reductions, whereas land-use changes are long-term sustained soil erosion control measures. It may be more efficient to combine check dam construction with revegetation strategies.
植被恢复和淤地坝建设是中国黄土高原广泛应用的两种水土流失控制措施，它们在减少泥沙输出方面发挥了重要作用。然而，这些大规模的土地利用变化和河道结构如何影响流域尺度的产水量和输沙量仍不清楚。本研究采用野外工作和模型模拟相结合的方法，定量评估了土地利用变化和淤地坝建设对武定河流域水文过程的影响。研究区在 1980 年至 2010 年间经历了重要的土地利用变化，林地和草地面积增加，耕地面积减少。从 1970 年到 1980 年，修建了大量的淤地坝。流域的径流量和输沙量呈显著减少趋势（P<0.01），变化点出现在 20 世纪 70 年代初。人为活动分别贡献了 75%和 89%的径流量和输沙量变化。模拟结果表明，在没有淤地坝的情况下，径流量和输沙量分别增加了 12%和 11.7%。植被恢复减少了径流量和输沙量。“退耕还林”导致径流量和输沙量减少，与将耕地转化为草地的情景相比，退耕还林具有更强的水文调节作用。此外，植被恢复和淤地坝建设的结合对产水量和输沙量的影响更大。淤地坝提供了短期的防洪和减沙效果，而土地利用变化是长期的可持续水土流失控制措施。将淤地坝建设与植被恢复策略相结合可能更为有效。
