鍏抽敭璇�: 姘寸敓鎬佸姛鑳�, 姘寸敓鎬佸垎鍖�, 绌洪棿鑱氱被, 澶箹娴佸煙

Abstract: Aquatic ecoregions have been used as spatial units for aquatic ecosystem management at the watershed scale.According to the protection requirements and characteristics of aquatic ecosystems in the Taihu Lake basin, the main purpose and the principles of level 鈪� aquatic ecological function regionalization delineation in this basin were proposed.Then the indicators for delineating level 鈪� aquatic ecological function regionalization were established based on regionalization objective and principles.The indicators for delineating level 鈪� aquatic ecological function regionalization in the non-Taihu Lake area included benthic Shannon-Wiener diversity index, chlorophyll content, water habitat types and benthic indicator species types (including Ephemera, Bivalvia, snail, Chironomidae and Oligochaeta), and the regionalization indicators for delineating level 鈪� aquatic ecological function regionalization in the Taihu Lake area included benthic Shannon-Wiener diversity index, chlorophyll content, water flow velocity and benthic indicator species (including Oligochaeta, Chironomidae class, Bivalvia, snail and others) ratio.With the aid of GIS technology, the spatial distribution of the indicators for level 鈪� aquatic ecological function regionalization delineation was identified based on the raster data from 1106 aquatic ecoregion function units in the non-Taihu Lake area and 3568 aquatic ecoregion function units in the Taihu Lake area, respectively.Two-step spatial clustering analysis approach and manual-assisted method were used to delineate level 鈪� aquatic ecological function zones.Then the Taihu Lake basin was divided into 21 level 鈪� aquatic ecological function zones.Moreover, the characteristics of the 21 zones were summarized, showing that there were significant differences in the aspects such as topography, soil type, water quality and aquatic ecology. The results of quantitative comparison of aquatic life also indicated that the benthic dominant species, Shannon-Wiener diversity index, chlorophyll a concentration and aquatic habitat types showed great spatial variability among the 21 zones.There existed spatial heterogeneities and the uneven features of aquatic ecosystems in the Taihu Lake basin.

Key words: aquatic ecological function, aquatic ecoregion, spatial cluster, Taihu Lake basin