Abstract: Sustained and intensive human activities have serious impact on the he alth and security of aquatic ecosystems. It is one of the keys to coordinate eco nomic development and ecological protection at watershed scale by discriminating aquatic ecological function, establishing aquatic ecological function regions, and rationally administrating water resources based on different functions. Thro ugh the analysis of the development in the concept, definition, characteristics, and approach of aquatic ecological function region at watershed scale (AEFRWS), this paper proposed the principles, indicators, and methods of AEFRWS regionali zation, and provided basic information for the establishment and improvement of the theories and approaches of AEFRWS in China.

Key words: Soil auger, Root index, Root biomass, Root distinction coefficient, Abandoned land, Loess Plateau