黑河流域水循环系统的分布式模拟(Ⅱ)——模型应用

应用作者开发的分布式水文模型WEP－HeiHe，对黑河上、中游流域水收支和水循环要素的时空变化进行了系统剖析；同时，还将模型应用于莺落峡径流预报、山前小河流径流和地下水侧渗量的模拟与预报以及未来下垫面变化条件下的流域水收支预测。结果表明，模型能系统表征流域水循环和水收支各要素的时空分异；对于枯水期的径流预报，达到较高的精度。在对下垫面变化条件下流域水收支预测中表明，尽管涵养林建设增加了截留蒸发，但同时也降低了林地的土壤蒸发，因此总蒸发量增加不明显；涵养林建设会使出山径流略有减少，但同时会稍增加土壤和地下水的蓄变量；退耕还牧对减少蒸发、增加正义峡下泄水量以及降低蓄变量赤字均有明显效果。

Distributed model of hydrological cycle system in Heihe River basin Ⅱ. Applications

The water budgets and spatial-temporal variations of hydrological cycle components in the Heihe river basin are studied by using the distributed hydrological model developed by the authors. The river flow including the monthly runoff in a year and the flow in dry season and flood season are forecasted.Furthermore, the model is also utilized to forecast the discharges of small rivers in front of mountains and lateral infiltration of groundwater from mountains, and predict the possible changes of the water budgets in the basin when the underlying conditions is changed. The results show that the model can systematically describe the water budgets and their spatial-temporal variations in the basin and precisely forecast river flows in dry season. The predicted water budgets for changed underlying conditions by using this model show that in spite of the forest for water conservation may cause the slight increase of interception evaporation but it reduces the evaporation of soil, so that the total evapotranpiration will not significantly increase. The forest for water conservation makes the runoff outcome from mountains slightly decreased but the storage of soil water and groundwater will increase. The countermeasure of changing the cultivated farmland into grassland is effective in increasing the river flow and decreasing the deficit of groundwater storage caused by over exploitation in the middle reaches area of the basin.