Abstract: In this paper, the concept of ecological migration was redefined, both in connotation and in extension. It was considered that ecological migration was the involuntary migration implemented by government, aimed to protect, restore and recover the seriously degraded local ecosystem. The underlying relationship between land desertification and ecological migration in northern China was analyzed from the aspects of self-examination of anti-desertification strategies and of population threshold for serious land degradation, which suggested that effective coordinating mechanism of human-land relationship could be worked via ecological migration activities. The groundwork, characteristics, and problems associated with the pilot projects of ecological migration in northern China were summarized after investigating two pilot ecological migration villages of Malaqin and Luanjingtan. The most urgent task at present was to push the assessment and monitoring work associated with ecological migration to reduce the economic, ecological, and societal risks.

Key words: Urban water system, Eutrophication, Characteristics, Factor analysis, Stepwise regression