Structural Characteristics and Diversity of Typical Shrub Plant Community in the Urumqi Region

According to the quadrat investigation material and TWINSPAN classification,we analyzed the community structure and diversity of typical shrub community by the species composition,floral feature and species diversity.The results showed that:(1)The investigated plants belong to 169species(including 36kinds of shrubs,133kinds of herbs),118genera and 31families.Most plants belong to chenopodiaceae, compositae and gramineae,which were the characteristic families in arid region.The ancient Mediterranean and West Asia to Central Asia and the North temperate distribution pattern are the dominant flora.(2)Using the TWINSPAN method,the typical shrub communities in the 50plots were sorted into ten types.The shrub community species diversity indexes are generally low,in which the species diversity indexes of Berberis heteropoda+Rosa platyacantha+Spiraea hypericifolia community are larger;and the species diversity index of Juniperus sabina community,R.platyacantha+Caragana pygnaea community and Halimodendron halodendron+Kaschgaria komarovii community are second,Tamarix chinensis+Reaumuria son-garica+Sarcozygium kaschgaricum are lower.(3)The shrub community belongs the thicket vegetation and the species diversity indexes of herb are larger than the shrub layer.The community is classified by desert vegetation types,the species diversity indexes of shrub are larger than that of the herb layer.