Methane production potential and emission at different water levels in the restored reed wetland of Hangzhou Bay

Changes in the hydrological conditions of coastal wetlands may potentially affect the role of wetlands in the methane (CH(4)) cycle. In this study, the CH(4) production potential and emissions from restored coastal reed wetlands at different water levels were examined in eastern China at a field scale in two phenological seasons. Results showed that the total CH(4) flux from reeds at various water levels were positive, indicating that they were “sources” of CH(4). During the peak growing season, CH(4) flux from reeds was greater than that during the spring thaw. CH(4) flux from reeds in inundated conditions was greater than that in non-inundated conditions. The CH(4) production potential during the peak growing season was far greater than that during the spring thaw. However, the effect of water level on wetland CH(4) production potential differed among seasons. The correlations among CH(4) production potential, soil properties and CH(4) flux change at different water level. These results demonstrate that water level was related to CH(4) production and CH(4) flux. The growing season also plays a role in CH(4) fluxes. Controlling the hydrological environment in restored wetlands has important implications for the maintenance of their function as carbon sinks.