Nitrogen And Phorsphorus Transformation Among Plant-soil System Under Typical Communities In Nanjishan Wetland

Wetland is an important natural resources.Nanjishan wetland lies in the south of Poyang lake,which is the typical wetland in Mid-tropical.In this research, we choose three transects in Nanji wetland to carry out our research.we select plants-soil systen in the community of Triarrhena lutarioriparia L.Liou and Carex cinerascens Kukenth.as our study.Systematically carried out plant biomass and its main elements and nutrients in the soil organic carbon, nitrogen, phosphorus-wide changes in the seasonal dynamics.And compared nitrogen and phosphorus vertical distribution pattern of similarities and differences in the soil plant under different water levels The results are:(1)Analyze the seasonal composition change of Plant community and analyze the index of Biodiversity,the result shows that Biodiversity is higher in winter and spring in the community of Triarrhena lutarioriparia L.Liou than Carex cinerascens Kukenth.The dynamic change of Biodiversity in the community of Triarrhena lutarioriparia LXiou is flat,The community of Triarrhena lutarioripara L.Liou is more stable than the community of Carex cinerascens Kukenth.in Nanji wetland.(2)The accumulated amount of total nitrogen and total phosphorus of Triarrhena lutarioriparia L. Liou and Carex cinerascens Kukenth.is varied with season,and the differences between diferent species and diferent organ are obviously. The accumulated amount of nitrogen is much higher than phosPhorus in two kinds of plants.In the same period, the absorption amount of the nitrogen is twice than that of Phosphorus in these two kinds of plants. In the Triarrhena lutarioriparia L. Liou of over and under the ground, Peak value of nitrogen occurs in October, similarly peak value of phosphorus occurs in May which is respectively. Meanwhile in the Carex cinerascens Kukenth. of over and under the ground, Peak value of nitrogen occurs in October, similarly Peak value of Phosphorus occurs in February which is respectively.(3)Spatial distribution of organic matter and total nitrogen (TN)and total phosphorus(TP)in wetland soil was studied. The results show that organic matter and TN content in surface soil are obviously higher than those in subsoil, The variant tendency of vertical distributions of TN and organic matter gradually decreases from the upper to the lower layer.In different community of plant, organic matter and total nitrogen in district quagmire are all the lowest.At the same time,we analyze the reserves of organic matter and total nitrogen and total phosphorus in two plant community Vegetation type had definite effects on the content and stock of organic matter,TN and TP in the marsh profiles.(4)The organic matter and TN, TP in the community of Triarrhena lutarioriparia L. Liou surface soil are much higher than those in the community of Carex cinerascens. Kukenth.In the same community soil TN,TP show difference in the different water level. The surface soil TP in the low water level is much higher than high level in the community of Triarrhena lutarioriparia L. Liou and Carex cinerascens Kukenth.(5)The dynamic change of plants accumulated TN, TP and soil TN, TP during different seasons suggests that the interactions between TN and TP of plant and soil in the community of Carex cinerascens Kukenth.very significant. And in the community of Triarrhena lutarioriparia L. Liou the interactions of TN between plants and soil also very significant.