title: [Species diversity of pasture community at different altitude levels in Qilian Mountains].
abstract: According to the occurring frequency and life form of plant species at different altitude levels, this paper studied the changing characteristics of the species a diversity of pasture community at the altitude from 2500 m to 3000 m in Qilian Mountains. The results showed that with increasing altitude, the Shannon-Wiener species diversity index increased from 1.432 to 1.832, and the variety of Simpson index was very complicated. An altitude of 2701-2800 m was an important turning point for species diversity. In pasture community of Qilian Mountains, the percentage of the poisonous and the less edible species exceeded 50%, and their biomass was more than 60% of the total biomass of the community. The biodiversity showed a degraded trend.
authors.affiliation: Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China. chxx@ns.lzb.ac.cn
authors.forename: Xuexiang
authors.initials: X
authors.lastname: Chang
authors.forename: Wenzhi
authors.initials: W
authors.lastname: Zhao
authors.forename: Aifen
authors.initials: A
authors.lastname: Zhao
mesh_terms: D000531:Altitude; D044822:Biodiversity; D018533:Biomass; D002681:China; D003247:Conservation of Natural Resources; D006109:Poaceae / Q000254:growth & development*; D013045:Species Specificity