中文摘要：

本文从生态系统水平衡和生物水分生理的角度，初步分析了不同类型生态系统生态需水核算的关键环节，并构建了竞争用水条件下我国生态需水研究的基本体系。结合国内外相关研究的新进展，剖析了我国生态需水研究的关键命题。结果表明，生态需水计算的关键是要核算维持生产者的正常生命活动和非生物环境分别向外界释放的水量，不同类型的生态系统对核算的侧重点也不相同。在竞争性用水条件下，我国生态需水研究，需要在系统识别水分一生态耦合作用机制和定量确立区域动态生态目标的基础上，充分考虑水分生态效益率，合理确定生态需水量。在生态与环境系统及国民经济系统之间。对区域可配置的水资源量进行合理配置，并提出了区域生态需水的风险管理方案。

英文摘要：

Based on the balance analysis of ecological system and the physiological principle of water, the improtant problems in calculating ecological water demand for different ecological system are analyzed and the frame of research work on ecological water requirement under the competitive condition of water use is worked out. The topics of the research work in this field are suggested according to the development status. It is shown that the most important parts of ecological water demand include the water sustaining the producers＇ normal activities in life and the water for adapting the abiotic environment. Under the competitive conditions of water use the emphases of research work in China should laid on the coupling mechanism between water and ecology as well as the quantitative establishment of regional dynamic ecological objectives, in which the benefit of hydro-ecology, the determination of rational ecological water demand must be considered. On this basis, the rational allocation of regional water resources paying attention to both ecological environment and economical development is suggested and the risk management scheme for regional water demand of eco-environment can be worked out accordingly.