基于SWAT模型的长江源区径流模拟

Runoff Simulation of the Catchment of the Headwaters of the Yangtze River Based on SWAT Model

长江源流域位于青藏高原腹地青海省境内,是气候变化的敏感区,其流域径流量的变化对区域经济发展和三江源生态环境保护具有重要的意义。SWAT模型是基于水文过程的,具有很强物理机制的流域分布式水文模型。利用长江源区1975-2004年气象数据、水文数据以及土地覆被/土地利用图、土壤图等数据构建了适合长江源区的SWAT水文模型。结果表明,模型对模拟的月流量相对误差为10.6%,相关系数R2和Nash Suttcliffe系数Ens>0.7。表明模型在长江源流域对产流模拟的适用性较好,为长江源流域建立分布式流域水文模型提供了参考。

The catchment of headwaters of the Yangtze River is located within Qinghai Province of Tibetan Plateau. The catchment is sensitive to the climate changes and the runoff is vitally important to the region- al development and ecology protection in the headwaters of the ＂Three River＂ areas. The soil and water as- sessment tool （SWAT） is a distributed model that is based on the hydrology process. We built a distribu- ted hydrological model suitable for describing the headwaters of the Yangtze River basin based on the SWAT model with meteorological data, hydrology data, land use/land cover and soil texture data. The simulation based on 1975--2004 data in the basin was successful. The relative error of the simulation （RE） of monthly runoff was 10.6% compared to the observed data. The Nash efficiency coefficient （Ens） and 172 were both larger than 0.7, indicating that the simulated results were reliable, and could provide the refer- ences for developing distributed models in the Headwaters of the Yangtze River basin.