The Biological And Ecological Basis Of Population Diffusion Of Sophora Alopecuroides

Sophora.alopecuroides L., a clonal plant, regenerates by rhizome, and also by seeds. Some area in inner Mongolecies we find the community is unity, S.alopecuroides L. grows with little other species. This extremely affects the bio-diversity and stability, and also it has important influenced to community succession. So studying on growth mechanism, regeneration characteristics, population expansion has important significance. The purpose which research the seedling characteristic, asexual reproduction, sexual reproduction, and the difference of population is to analyze the intrinsic reason and extrinsic elements, which effect the population expansion. The results showed that S.alopecuroides L. could germinated when it growed over three years, and produced buds from the rhizome. This took place mostly in spring, and could produced little buds later. S.alopecuroides L. regenerated mostly by the extension of rhizome, and had more rhizomes in sand than in clay, which accelerated the population expansion in sand. The seedlings were able to bear the sand burial,and specified sand burial also could accelerate the growth. With strong sand blown by wind, the plant formed a capability of survival; this paved a road for settling in sand. S.alopecuroides L. had strong capacity of asexual propagation, this was in favor of the stability and expansion of population in small area. But the distant transmission had to dependent on the seed. It had many ways. Animals had important role to the dispersal. After animals eat seeds, the thick testa was hardly digested in intestinal canal but relieve dormancy. With animals move, the seed could be spreaded in large-scale. The seed had bean-pod, so it also could be spreaded distantly by water. S.alopecuroides L. seeds were big and weigh, most existed in local seed bank. Their long lifetime was important for the stability and updating of population. Moreover,The vegetation changes of pasture at over grazing and no grazing were investigated to explore impact of grazing on plant diversity and community succession.