基于SWAT模型的长江源区巴塘河流域径流模拟

Simulation of Runoff in Batang River Basin in the Source Area of Yangtze River Using SWAT

为了分析长江源区巴塘河流域气候变化与径流的水文响应关系,根据研究区的DEM(digital elevation model)、气象数据、土壤类型和土地利用数据,建立了SWAT(Soil and Water Assessment Tool)模型,并选用SUFI-2(Sequential Uncertainty Fitting)算法进行SWAT模型参数的矫正及验证。模拟结果表明:矫正期与验证期的模拟径流量与实测流量的峰值出现月份基本一致,均在巴塘河流域的6—9月份,最小值出现月份均在巴塘河流域的1,2月份,地下水延滞参数为影响模拟结果的首要因子。矫正期与验证期的模拟径流量与实测径流量之间的确定性系数及效率系数都高于0.8,该模型对巴塘流域的模拟效果良好,但受冻土影响较大。通过径流模拟及影响因子分析,可为巴塘河流域的山洪泥石流灾害预测、风险分析与管理提供参考。

To analyze the hydrology response of climate change and runoff in Batang River basin in the source area of Yangtze River, SWAT（ Soil and Water Assessment Tool） model was established based on the DEM （Digital Ele- vation Model）, meteorological data, soil type and land use map data. Furthermore, SUFI-2（ Sequential Uncertainty Fitting） was employed to calibrate and validate the model. The simulation results showed that the peak values of ob- served and simulated runoff were roughly similar, and the peak values were in June, July, August and September; the valley values were in January and February. Factor of groundwater delay was the most essential factor affecting the simulation result. The determination coefficient and efficiency coefficient of the simulated and observed runoff both in calibration period and validation period were all greater than 0.8, indicating that the SWAT model is suit-able for the Batang River basin, but was largely affected by frozen soil. On the basis of runoff simulation and analysis of affecting factors, better risk analysis and prediction of mountain torrents and debris flow hazards for the Batang River basin will be taken according to the previous work.