The Study On Species Diversity And Dominant Populations Niche Of Different Communities In Ebinur Lake Wetland

The Ebinur Lake Wetland natural reserve district is the most representative of the temperate zone wetlands in arid desert ecosystems.is in a typical high conservation value of China's natural ecosystems .It can regulate climate, maintain the ecological balance of the region. Through investigating the typical communities of desent plant and analysing the physical and chemical properties of soil in Ebinur Lake wetlands , and using related analytical tools, this study makes further research on the distribution of plant communities in desert and the relationship between species, diversification with soil environmental factors. Then the thesis provides theoretical and referential guidance for nursine and restoration of desert vegetation.The major 42 plant species in the ebinur belonged to 36genera,16 families.most were natural reserve district's plants andwere classified into 16 groups. The importance value of species Halostachys caspica, Halocnemum strobilaceum, Haloxylon ammodendron Haloxylon persicum Bunge and Kalidium foliatum is higher in the study area,but herb plant's is lower. The species diversity and evenness of the communities were in the order of Haloxylon persicum Bunge > Populus euphratica > Halostachys caspica > Halimodendron halodendron > Apocynum venetum L > Reaumuria songarica > Karelinia caspia > Nitraria > Tamarix> Poacynum pictum > Phragmites australis > Achnatherum splendens > Haloxylon ammodendron > Alhagi sparsifolia > Glycyrrhiza uralensis Fisch > Halocnemum strobilaceum.Analysis of community species diversity of desert plant based on important value,cover value and abundance in the ebinur lake wetland suggests that diversity index based on important value is more reasonable than that of cover and richness. However, the change trend of three indexes is identical by and large. Moreover the correlation analysis about 11 kinds of species diversity indexes indicates that community species diversity in desert region is influenced mostly by evenness and abundance. And the relation between evenness and diversity is higher than the relation between abundance and diversity. In other words, species diversity rests principally with evenness in desert plant community.Analyzing the correlation species diversity and soil factors by regression, the conclusions indicate that diversity index(Dm) and Evenness index(Jsw,E) decreased as total salt in soil, fitting negative correlation; species diversities(H) and richness(Ma,Mo,R) increased as soil pH while Dominance index decreased,all index and soil organic matter do not have the relevance.Through the main plant species, niche breadth and niche overlap in 16 typical communities of Ebinur Lake wetlands from three dimensions which are the soil acidity, salinity and organic matter,it can be on analyzed that in all communities, the niche breadth of the species which is the most dominant in community is the largest, which shows that the reason why they have wider niche breadth is that they have wider distribution and a large number, and they occupy the majority of resources and adapt to specific ecological environment, and fully use of resources, and have the strongest competitive Capacity.The wider niche breadth of plant species ,the greater the opportunity of niche overlaps with other species and the narrow niche breadth , the less of the opportunity .This shows that the species which has wider niche breadth will have larger niche overlaps with other species .