Gao Shuang, Ti Chao-Pu, Tang Shui-Rong, Wang Xin-Liang, Wang Hui-Yong, Meng Lei, Yan Xiao-Yuan
College of Tropical Crops, Hainan University, Haikou 570228, China.
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
Huan Jing Ke Xue. 2023 Sep 8;44(9):4853-4862. doi: 10.13227/j.hjkx.202210150.
Studies on runoff are crucial for the scientific allocation, utilization, and development of water resources and can provide an important basis for the prevention and control of flood and drought disaster, as well as water environmental pollution management. Affected by global warming, the frequency and intensity of extreme climate events, particularly extreme precipitation, have significantly changed in recent years, which can directly or indirectly impact runoff changes. In this study, we used the SWAT model to simulate the spatiotemporal variations in runoff in the Yangtze River Basin from 1965 to 2019 and analyzed the response of runoff to precipitation under extreme conditions. The results showed that the changes in total runoff in the Yangtze River Basin were not significantly different from 1965 to 2019. The total runoff and the mid-lower runoff in the basin experienced four stages of "dry-wet-dry-wet." Simulations revealed that under the 50-year extreme precipitation event, the increase in daily average runoff was 6200%, 21%, and 15% for the typical sub-basins of the upper, middle, and lower reaches of the Yangtze River, respectively. Additionally, the increase in monthly and annual average runoff was 355%, 5%, and 1.3% and 78%, 1%, and 0.24%, for upper, middle, and lower reaches of the Yangtze River, respectively. Moreover, under the 100-year extreme precipitation, the average daily runoff increasing rates were 8000%, 25%, and 17% for upper, middle, and lower reaches of the Yangtze River, respectively, compared to the monthly increase of 437%, 7%, and 1.5% and annual increase of 96%, 1.2%, and 0.28%, respectively. Our findings may improve the understanding of hydrological responses to climate change and provide valuable inferences to decision-makers and water managers for better allocation and management of water resources.
径流研究对于水资源的科学分配、利用和开发至关重要，可为防洪抗旱灾害防治以及水环境污染治理提供重要依据。受全球变暖影响，近年来极端气候事件的频率和强度，尤其是极端降水，发生了显著变化，这会直接或间接影响径流变化。在本研究中，我们使用SWAT模型模拟了1965年至2019年长江流域径流的时空变化，并分析了极端条件下径流对降水的响应。结果表明，1965年至2019年长江流域总径流量变化不显著。流域内总径流和中下游径流经历了“干-湿-干-湿”四个阶段。模拟结果显示，在50年一遇的极端降水事件下，长江上游、中游和下游典型子流域的日平均径流量增幅分别为6200%、21%和15%。此外，长江上游、中游和下游的月平均径流量增幅分别为355%、5%和1.3%，年平均径流量增幅分别为78%、1%和0.24%。而且，在100年一遇的极端降水情况下，长江上游、中游和下游的日平均径流增加率分别为8000%、25%和17%，月增加率分别为437%、7%和1.5%，年增加率分别为96%、1.2%和0.28%。我们的研究结果可能会增进对气候变化水文响应的理解，并为决策者和水资源管理者提供有价值的参考，以便更好地分配和管理水资源。
