针对地表水开发利用过程中存在的主要问题,从理论上对河道生态、环境需水进行探讨,包括:①在分析已有生态及环境需水概念的基础上,界定了生态及环境需水的定义;②对河道生态及环境需水进行了重点分析和论述。首先,回顾了与河道生态及环境需水研究有关的概念;其次,根据河道水量平衡探讨河道生态及环境需水的机理及其组成;第三,根据人类对地表水的影响强度,将水资源开发利用划分为4个阶段,论述了每个阶段河流生态系统的特点,并分析了河流流量减少所造成的对整个河流生态系统的影响;最后,给出了河道生态及环境需水的概念。论文为河道生态及环境需水研究提供了理论基础和依据。

For solving the problems occurred in the process of surface water utilization,the the-ories of ecological and environmental water requirements of river course are studied in this pa-per.The following conclusions are mainly drawn:(1)Based on the analyses of the old concept s of ecological and environmental water requirements,definitions of ecological water requirement and environmental requirement are given.(2)The ecological water requirements and environ-mental water requirement of river course are expounded especially theoretically.Firstly,the con-cepts related to the research of ecological and environmental water requirements of river course have been reviewed.Secondly,the mechanism and composition of ecological and environmental water requirements of river course are discussed according to the balance of river water quantity.Thirdly,according to the impacting intensity of human being on surface water,the exploitation and utilization of water resources are divided into four stages,and the characteristic of river e-cosystem of each stage is described.The impacts of river flow reduction on the whole river e-cosystem are analyzed.Finally,the concepts of ecological water requirement and environmental water requirement of river course are given on the basis of the above analyses.The research of this article can provide some theoretical foundation and basis for the study of ecological and en-vironmental water requirements of river course.