The Study On Nitrogen And Phosphorus Changes Of Plant–soil System In The Poyang Lake Wetland

Wetlands are valuable natural resources. The Poyang Lake is the largest freshwater wetland in China,it is one of the natural wetlands which had been firstly included in the list of the world’s important wetlandsin our country, and it was divided into one of the most important ecological regions in the globe by theWorld Wide Fund for Nature (WWF). Transformation of nitrogen and phosphorus in wetland plant-soilsystem is part of the biogeochemical cycling. Based on the field sampling and laboratory analysis, thedynamic changes and transformation characteristics of nitrogen and phosphorus in the different water levelgradients of the Poyang Lake Carex cinerascens wetland plant-soil system was comparatively studied, theresults can reveal the effects of the Carex cinerascens growth on the distribution, migration andtransformation of nitrogen and phosphorus in wetlands, provide theoretical basis and data support for thefurther studies on the biogeochemical cycling law and force of the nitrogen and phosphorus in wetlands,and contribute to increased awareness of the ecological service function of Carex cinerascens wetland inPoyang Lake. Conclusions are as follows:The biomass, nitrogen and phosphorus accumulation of the Carex cinerascens and its seasonalvariation show seasonal differences at each elevation zone. Phosphorus content of aboveground parts andunderground parts reach the highest value in early March. but the time to reach the highest value of itsnitrogen content is different. Some differences of the nitrogen and phosphorus accumulation can be foundin.the different elevations.Soil nitrogen content of the each elevation shows clear vertical distribution rule, and the nitrogencontent of0-10cm soil is highest in all elevation zones, but the vertical difference of phosphorus is notobvious.The soil nitrogen and phosphorus content in different elevation shows obvious horizontal differences,and, soil nitrogen content of the low elevation is less than that of the high elevation.By studying on month variation of nitrogen and phosphorus accumulation in plants and nitrogen andphosphorus content in soil, the correlation of nitrogen between plant and soil is more significant in Carexcinerascens wetland.