中文摘要：

将河流生态环境需水分为河流基本生态需水量、河流水污染防治需水、河流水面蒸发生态需水量、河流输沙需水,讨论了实现河流各项功能目标的各部分估算方法;提出了河流生态环境需水的阈值确定原则和方法,以及生态系统健康评价指标和评价标准;为河流健康评价提供了理论依据,对于提高河流健康评价的有效性及河流综合管理能力具有重要意义。

英文摘要：

According to various river functions, water demands for eco-environment are classified into four parts： basic ecological wa- ter demand by rivers, water demand of pollution prevention, water demand of river water surface evaporation, water demand of transporting sand. In order to achieve the aim of various river functions, different kinds of calculation methods for water demand of river eco-environment are discussed. Based on this, principles and methods for determining the reasonable amount of river eco-envi- ronment and corresponding threshold are proposed, and index and standard of river health assessment are also introduced. It offers a theoretical basis for assessment of river health, and it is important to enhance ability of river integrated management.