Characteristics of soil seed bank in the regions with different groundwater levels in lower reaches of Tarim River

Twenty-five natural vegetation plots with different groundwater levels in the lower reaches of Tarim River were selected,and their soil seed bank density,plant species diversity,life-form proportion,and similarity between plant communities and soil seed bank were studied by using seed-emergence method.The results showed that in arid regions,groundwater level not only affected the species and composition of plant communities,but also affected the density and composition of soil seed bank.With decreasing groundwater level,the degradation of plant communities also reflected on the changes of soil seed bank,e.g.,the decreases of soil seed bank density and plant species diversity,the simplification of life-form,and the decrease of the similarity coefficient between plant communities and soil seed bank.This study could help to the enrichment of theoretical knowledge of soil seed bank in arid regions,and also,the practice of ecological restoration in the lower reaches of Tarim River.