Characteristics of Plant Community Changes during the Restoration of Alpine Desertified Grassland in Northwest Sichuan

Grassland desertification is one of the serious environmental problems in China, but the research on grassland desertification mainly focuses on the effects of soil nutrient and enclosure on plants, but there are few concerns and researches on the changes of plant communities in the process of grassland desertification in China. Through field investigations, studies were made of the variation characteristics of plant communities during the desertification process of alpine grassland in northwestern Sichuan. The researches have shown that:(1) There are 33 species in the survey plot, belonging to 17 families and 29 genera; (2) the species richness index is also increasing with the increase of the repair period, but the species diversity change index and species uniformity index increase first and then decreas with the increase of the repair period; (3) The TWINSPAN quantity classification divides the plant community of the Zoige restoration site into 11 types; (4) The first axis of the sample DCA ranking basically reflects the change gradient of the repair period, The two axes basically reflect the change in altitude.