未来气候情景下兰江流域径流响应模拟

通过耦合SWAT水文模型和SDSM统计降尺度模型，研究全球气候变暖背景下兰江流域未来气候及其径流响应。选用2008～2019年兰溪水文站径流资料建立月尺度SWAT模型，将2030～2100年CanESM2模式RCP2.6、RCP4.5、RCP8.5三种情景数据降尺度到兰江流域各气象站点，生成未来气候数据并输入到已校准的SWAT模型，模拟未来气候变化下的径流响应。结果表明，未来兰江流域径流呈上升趋势，RCP8.5情景增幅最大，RCP2.6情景次之，RCP4.5情景涨幅最小。各时段年径流量呈不同变化趋势，RCP2.6情景下为增至峰顶后稳定，RCP4.5情景下为增至峰顶后减少，RCP8.5情景下为持续上升态势。

Response of Runoff over Future Period to Climate in Lanjiang River Basin

For the analysis of runoff hydrological response under the background of global warming in the Lanjiang River Basin, this paper coupled SWAT hydrological models with SDSM downscaling model. The monthly SWAT model was established based on the runoff data of the Lanxi Hydrological Station from 2008 to 2019. The scenario data of the RCP2.6, RCP4.5, and RCP 8.5 in CanESM2 model from 2030 to 2100 were downscaled to each meteorological station in the Lanjiang River Basin. Then the future climate data were generated and input into the calibrated SWAT model to simulate the runoff response under the scenarios of future climate change. The results show that the runoff of Lanjiang River would increase in the future, with the largest increase amplitude in the RCP8.5, followed by the RCP4.5 with the smallest increase amplitude. The annual runoff in different periods showed different variation trends. Under the RCP2.6, the annual runoff increased gradually to the peak value and then stabilized;Under the RCP4.5, it increased to the peak and then decreased;Under the RCP8.5, it exhibited a rapid rising trend.