Abstract: Wetland plays an important role in the global carbon cycle,which can degrade the carbon dioxide levels, slow down the greenhouse effect,and maintain the balance of ecological system. Carbon fixation is an important ecosystem service of wetland and the carbon cycle is realized mainly by the photosynthesis of green plants. The Ebinur Lake Wetland has rich vegetation,and plants in the wetland edge are very high in carbon sequestration capacity,which has an important effect on the ecological balance and economic development of the surrounding environment. Plants carbon pool has an important influence on the carbon sequestration capacity of wetland. In this paper,the carbon storage capacity and carbon storage of two kinds of plant communities,Phragmites communis and Tamarix chinensis,in the marginal zone of Ebinur Lake Wetland were calculated according to the plants carbon sequestration capacity and carbon storage which were studied at first. The photosynthesis data used in this study were measured by LI-6400 photosynthetic instrument produced by LI-COR Company of American. It took three days to measure the photosynthesis,and the measurement time is selected from 9:00 to 19:00 in summer. When measuring photosynthetic rate,the number of blades,plant height,crown width,leaf area index and surrounding environment conditions were recorded at the same time. The results show as follows:(1)The average size of carbon conversion ability of Phragmites communis was 2.4 g·m^-2·h^-1,while that of Tamarix chinensis was 2.2 g·m^-2·h^-1;The maximum net photosynthetic rate of Phragmites communis appeared at about 13:00 at noon, while for Tamarix chinensis maximum,it appeared about an hour later after midday.(2)In terms of the carbon storage amount in plant communities,it overall shows:Phragmites communis < Tamarix chinensis.(3)Through the correlation analysis between the carbon sequestration capacity and external environmental factors of Phragmites communis and Tamarix chinensis,the results show that external environment(PAR,Tair,RH,Ci)has an important influence on the carbon sequestration capacity of plants,but there are great differences between Phragmites communis and Tamarix chinensis. The importance of the external environmental factors for carbon sequestration capacity on Phragmites communis,from most to least,were ranked as:RH > PAR > Ci > Tair;while for Tamarix chinensis,they were ranked as:Tair > PAR > RH > Ci.(4)Phragmites communis and Tamarix chinensis have strong storage carbon capacity,and the amount of annual carbon storage of Phragmites communis is about 1.3×10⁸ t,Tamarix chinensis is about 1.6×10⁸ t. The carbon storage capacity of the two kinds of plant communities has an important significance for improving the ecological service for the Ebinur Lake Wetland. Therefore,increasing the area of Phragmites communis and Tamarix chinensis can help enhance and improve the function of the wetland carbon cycle.

Key words: Ebinur Lake Wetland, carbon sequestration capacity, carbon storage amount, Phragmites communis community, Tamarix chinensis community