N and P Dynamic of Phragmites australis and Typha angustata Litter in Dawen River Wetland During the Decomposition

The research used the bag method to explore the decomposition dynamic of Phragmites australis and Typha angustata which are location different environment in Dawen River wetland.The environment are the surface and 50cm under the surface.The results showed that: ①All treatments have the same tendency and three stages which include rapidly-slowly-rapidly decrease.The decomposition rate of Typha angustata is higher than Phragmites australis,and the mass remaining ration respectively are 38% and 43% after 10 months.Decomposition rate in the upper layer was more rapidly than the lower layer,Remaining mass of Phragmites australis and Typha angustata in upper layer and lower layer were 43.02%,58.01% and 38.31%,53.27%.②The content and NAI of N and P showed the fluctuation dynamic.At the end of the experiment the N and P content of Typha angustata is obviously lower than Phragmites australis.The N of Phragmites australis and Typha angustata are release from litter to environment and the P of Phragmites australis and Typha angustata are relocate from environment.All these result are important to understand the recycle of material in wetland.On the other hand,these results give some theory basement to the science management of wetland.