传统的概念性水文模型存在不能对不同径流成分进行精确模拟和划分的局限性。而分布式水文模型基于其精确的物理基础和产流机制，充分考虑到不同径流成分的水力联系，在对流域进行土壤垂直分层和水平网格划分后可进行地表水、地下水的交互作用分析与耦合模拟。应用李兰教授开发的LL Ⅱ分布式水文模型和GIS技术，以宜昌黄柏河天福庙水库作为典型流域，根据连续日入库径流资料验证模型精度，对该流域的日入库径流过程进行地表水和地下水的连续耦合模拟与预测，取得了较好的模拟预测效果。

The traditional conceptual hydrological model has its localization that cannt simulate and partition different runoff components accurately. However, after dividing vertical layers and horizontal grids to the watershed, a distributed hydrology model established based on the physical foundation and runoff producing theory could analyse the mutual effect and coupling simulation about surface water and ground water with considering hydraulic connection of different runoff components. This paper applies LL- Ⅱ distributed hydrology model developed by professor Lilan and GIS technology to Tianfumiao Reservoir watershed in Huangbohe River in Yichang City,and simulates and forecasts daily flow for this watershed on surface water and ground water coupling. Finally, through the application of an illustration, this method obtains a good simulated result.