|其他摘要||Urumqi, situated in the temperate desert region of Central Asia, is characterized by typical natural vegetation, among which are developed well with xerophytes, halophytes and psammophytes. In this study, typical shrub vegetation in Urumqi area was investigated. Based on the classification of shrub communities, combined with the quantity sorting theory and spatial variability of soil, the major environmental factors which affect shrub community diversity and distribution patterns were analyzed. The results will provide a scientific basis. The spatial distribution pattern and their driving factors, this is also of great significance in biodiversity conservation. And ecological restoration of shrub communities in arid areas. The main conclusions are as follows:
(1) The soil moisture content, the organic matter, the total nitrigen and avaliable phosphate of this area had a strong spatial autocorrelation and the spatial variability was caused by structural differences other than random factors. The soils in the study area are alkaline soil, and were basically in a state of mild salinization.
(2) The major shrub species occurred in the study area were totaling 11 families, 24 genera and 32 species, the most family of shrub was Chenopodiaceae, followed by Rosaceae, Legumes and Caprifoliaceae; the most genera was Rosa, followed by Lonicera.
(3) Simpson index of shrub communities was significant correlated with altitude, the altitude, mean particle size, heavy metals Bi, and particle sorting coefficient; Pielou index was significant positive correlated with the altitude, mean grain size, sorting coefficient and element Mn; Marglef index was only significantly associated with Bi.
(4) The sorted results showed that soil salinity, pH, organic matter, total nitrogen and total potassium content in soil environmental factors had an important role in the distribution of shrub communities. However salinity had the largest eigenvalues, and total phosphorus content had the lowest contribution value.
(5) The surface soil determined the distribution pattern of mountain shrub and desert shrubs, while, medium-shallow and deep soil layer had little and similar effect on it.|