河网城市不透水面快速扩展,已成为影响河流生态系统健康的主要因素,理解掌握区域不透水面与河流生态系统之间的压力响应关系十分必要。以国外研究为重点,从不透水面的识别技术方法、 流域不透水面与河流生态系统状况之间的压力响应关系、 不透水面在流域土地利用规划调控和河流管理应用等三个方面,回顾了不透水面研究的主要进展,特别对不透水面影响河流生态系统的阈值效应进行了较细致梳理。从研究区域、 研究视角、 研究方法、 决策应用等四个方面,讨论了当前研究可能存在的问题。结合河网地区较为特殊的水文地貌特点,提出了河网城市开展相关研究的主要任务,认为必须解决的若干关键技术方法问题包括:不透水面实地调查方法及与有效不透水面转换、 汇水单元及其多尺度体系、 压力响应体系构建,以及数据分析技术方法等。最后以上海地区为案例,分析了河岸带尺度上的不透水面与河流生态系统之间的压力响应关系。这一研究体系框架试图为相关实证研究提供可实际操作的方法论参考。

The rapid expanding of impervious surface in river network city has became a more and more important factor effecting the river ecosystem health, so understanding the pressure response relationship between the impervious surface and river ecosystem is of fully necessary. The international research history of impervious surface and its effect on river ecosystem has already past 40 years, and perfect theory and method system has already established, however, our current research is still at its initial stage. Focusing on overseas research, this paper reviews the main advances of impervious surface as the following three aspects: firstly the identification technical approach of impervious surface, then the pressure response relationship between river basin impervious surface and river ecosystem conditions, finally the application of impervious surface threshold in river basin land use planning regulation and river management, in particular a detailed analysis on the threshold effect of impervious surface is summarized in literature from 1960s. From four aspects including the research perspective, research methods, study area and decision-making applications, the current problems in the literature was diagnosed. Considering the special hydro-geomorphic characteristics of river network area, this paper puts forward the main task in river network city, propose methods to solve the key technical issues advanced by the authors, such as the field survey of impervious surface and how to transition it to effective impervious surface, the hydrological units and its multi-scale system, pressure response system, as well as the data analysis methods and so on. Finally, the typical river network city Shanghai was taken as a case, and at riparian scale the relationship between impervious surface and river ecosystem was detected, in which the result showed there was an obvious non-linear relationship. The framework in this paper would be expected to provide methodology references for forwarding empirical investigations.