Quantitative Classification and Ordination of Plant Vegetation in the Bosten Lake Wetlands

TWINSPAN, DCA and CCA methods were used to classify plant community types and determine the relationship between vegetation and environmental factors in order to evaluate the influence of environment regulation on vegetation in the Bosten Lake wetlands in Xinjiang. TWINSPAN results showed that the vegetation in this region could be divided into seven associations, which were distributed along the wetland shallow water zone, marsh zone, bush and tree lakeshore zone and xeric shrub zone. These associations were: Ass. Typha angustata, Ass.Phragmites australis+Ty.angustata, Ass.P.australis+Ty.angustifolia, Ass.Tamarix ramosissima-P.australis, Ass.Populus euphratica-Ta.ramosissima, Ass.Salix matsudana-Ta.ramosissima, Ass.Ta. ramosissima. These associations were also well reflected in the DCA ordination graph. The CCA results were basically consistent with the DCA results, and showed that the vegetation distribution patterns correlated with major environmental variables of soil water content and total dissolved solids. The species characteristics and ecological structures of wetland vegetation in the Bosten Lake wetlands were single and simple. Dynamics and interactions of water and salt were the main factors that influenced the distribution of vegetation in the area. This study confirmed that planners and managers of nature reserves in this area should take the two major environmental factors of soil water content and total dissolved solids, and species characteristics into account during decision-making processes.