太湖流域水生态功能分区

Delineation of aquatic ecoregions in Taihu lake basin

水生态功能分区是进行流域现代水资源管理的必然要求,是面向水质目标管理污染控制单元划分的基础。在发生学原则、区内相似性原则以及共轭性原则等相关原则的指导下,采用因素分析法对太湖流域一级水生态功能区进行划分,通过对流域DEM和气候、土壤等相关分区指标的比较分析,认为地形是太湖流域一级水生态功能分区的主导指标,分区结果主要包括西部丘陵水生态区和东部平原水生态区,并对两个一级水生态功能区的特征进行了阐述;在此基础上,对太湖流域水生态功能分区体系即分区等级体系、方法体系和指标体系进行了探讨。

Aquatic ecoregions are increasingly used as a spatial unit for planning and environmental management, and they have become an indispensable condition for environmental assessment and modern water resource management, and also are the basis of delineating the polluted control units oriented on the water equality targets management in basin scale. In this paper, factor analysis approach was selected and used to delineate the level I aquatic ecoregions in the Taihu lake basin under the guidance of the aquatic ecoregion delineation principles, mainly including principle of regional genesis, principles of integrity and relative consistency, principle of regional differentiation, principles of the combination of comprehensiveness and dominance, principle of regional hierarchy, principle of conjugation, etc. The results of analyzing DEM data, climate data, soil data and other related data, with the help of spatial analysis of geographic information system and expert judgment, indicated that topography was the main indicator of the level I aquatic ecoregions delineation. And then the Taihu lake basin was divided into two typical level I aquatic ecoregions, namely, western hill aquatic ecoregion and eastern plain aquatic ecoregion. Moreover, the characteristics of the two aquatic ecoregions in the Taihu Lake basin were summarized. Finally, the aquatic ecoregion delineation system in the Taihu lake basin was discussed. The aquatic ecoregion delineation system has a hierarchical framework, which can be divided into several levels, and different levels have different spatial scales. The delineation methods of aquatic eeoregion can be classified into two categories： direct and indirect methods of delineation, and the direct method of delineation can be further divided into the approaches of factor analysis and function analysis. The selection of environmental factors and methods used in the delineation of aquatic ecoregions at different levels will vary, and depend on the feathers of the aquatic ecosystems in different spatial scales in the Taihu lake basin.