Choice of wetland use pattern to minimize the impacts on soil carbon fixation and CO2 gas emission is the key for reasonable utilization of wetland and reduction of greenhouse gas emission. Wetland soil respiration is affected not only by environmental conditions

but also by soil traits. By a positioned experiment in Wanjing region

CO2 emission flux

air temperature

surface soil temperature of soils in natural wetland and different reclaimed lands during the non-cropping season were measured and their soil TOC contents were analyzed. The land use types

in order of decreasing CO2 emission flux

were paddy field[700.70 mg/(m2·h)]

dry land[433.80 mg/(m2·h)] and natural wetland[302.66 mg/(m2·h)]. The soil TOC content of natural wetland was significantly higher than that of reclaimed dry land and paddy field (0-30 cm depth)

indicating that the contribution of natural wetland to atmospheric CO2 concentration was the lowest. Therefore

compared to dry land and paddy land

wetland is capable of storing more carbon. The correlation between CO2 emission flux and temperature was also discussed. It follows from the discussion that CO2 emission flux of the three land types is positively correlated with both of atmospheric temperature and surface soil temperature.