Abstract: In the agriculture pasture ecotone, due to its specific natural condition, the natural system is unstable, the self regulation capability is weak, the equilibrium is easily broken, and hence the habitat is fairly vulnerable. During last 20 years, the increasing population and livestock, over-reclamation, over-grazing, over-deforesting, and other intensified negative human activities in this area resulted in surface soil coarsening, organic matter content in soil decreasing, vegetation coverage decreasing, community structure varying and degrading, and hence desertification of the land was aggravated. The results also proved that there was close correlation between desertification and the variations of soil and surface vegetation.

Key words: Agriculture pasture ecotone, Organic matter, Desertification