Research on the hydrological cycle model of basin ecosystem and the system for water resource management

本研究的目的是明确“流域生态系统”在流域水循环中的作用，构建流域水资源管理系统的“生态系统水循环模型”和“综合流域生态系统水循环模型”。研究了森林和耕地的蒸散量和河流水质的形成机理。应用Penman-Monteith方程估算各区域的总蒸散量。进行了各种实地研究工作，以验证模型。并对地下水水质的形成过程及近岸海域进行了评价。上游流域的植被特征对下游河水的水质和水流特性有很大的影响。估算不同林分类型的蒸散量及其分布对于认识陡坡森林区基流的形成具有重要意义。我们的研究结果表明，未管理的人工林流域作为一个扩散源的养分。在我们的研究工作中，长期的生态系统研究的重要性提出。

The objectives of this research are to clarify the function of "Basin ecosystem" in the hydrological cycle and to construct "Ecosystem water circulation model" and "The synthetic basin ecosystem water circulation model" for the basin water resource management system. The amount of evapotranspiration and the formation mechanism of the river water quality in the areas of forests and the cultivated fields were studied. Penman-Monteith equation was applied for the estimation of total evapotranspiration of each area. Various field research works were conducted to verify the models. Furthermore, the formation process of the quality of groundwater and the coastal sea area were evaluated. The characteristics of vegetation that covers the upper reaches basin gave great influences on the water quality of the lower reaches river water and the flow characteristic. It is important to estimate each stand type of evapotranspiration and its distribution for understanding baseflow generation in the steep forested chatchments. Our results suggested that the unmanaged artificial forest watershed worked as a diffuse source of nutrients. Throughout our research works, importance of the long-term ecosystem research was suggested.