Effect of salinity and flood on the dissolved organic matter content and composition structure in the early stage of decomposition of Cyperus malaccensis litter

In this study, we chose the withered litters of Cyperus malaccensis in Min River estuary wetlands as the research object, adopting different salinity（0,5,10,15） and flooding degree（unimmersed litterbags, flooded treatment Ⅰ and continuous immersion litterbag, flooded treatment Ⅱ） to do experiments on decomposition of the withered litters, of which its dissolved organic matter（DOM） content and structures of UV-visible spectroscopy, Fluorescence Spectroscopy, and Infrared Spectroscopy with changes in characteristics and so on. The results of this study show that the concentrations of dissolved organic carbon（DOC）, total soluble nitrogen（DTN）, dissolved inorganic nitrogen（DIN） and soluble organic nitrogen（DON） are of significant difference under the condition of different salinity and flooded treatment in the decomposition time（P