Spatial variation of plant diversity and vegetation-environment relationships in the south part of Gurbantunggut desert, Xinjiang, China

This study provides an analysis of environmental factors, vegetation types as well as species distribution in 46 sites in the southern part of Gurbantunggut desert, and focuses on the vegetation-environment relationships. A total of 104 species belonging to 80 genera, 27 families of the vascular plants are recorded. The largest families were Compositae, Chenopodiaceae, Cruciferae and Leguminosae. Hemicryptophytes and therophytes were the most abundant life-form. The woody perennials constitute only 19.2% of the recorded species, while grasses are highly dominated (80.8%).The distribution relative frequency of majority species were lower; Species distribution reveal obvious heterogeneity of aspect of the longitude , latitude and slope position. Classification of the vegetation is analyzed using two-way indicator species analysis (TWINSPAN) techniques resulted in the recognition of eight vegetation groups. Ordination techniques as detrended correspondence analysis (DCA) and detrended canonical correspondence analysis (DCCA) are used to examine the relationship between the vegetation and environmental parameters. The first two axes explaining 36.98% of the cumulative variance. As a whole, the macroenvironment factors including PRE, ELEV, LAT and LONG are primary environmental factors affecting spatial variation of plant diversity, in which PRE is the most important factor, soil factors are relatively weak. These findings provide a fundamental step in selecting different vegetation types and focusing on the main limiting factors in management and ecological restoration in the desert. c 2009 IEEE. (28 refs.)