Vertical Pattern And Month Variation Of Porewater Acetate And Relation With Methane Production,Emission In Marshes In The Min River Estuary

The Min River estuary wetland is one of the most representative estuarine wetlands in the southeast of China. Spartina alterniflora and Cyperus malaccensis are the two main dominant plant species in the Min River estuary. Vertical patterns and temporal variations of the concentrations of formic, acetic acid, dissolved methane, carbon dioxide, and sulfate in the porewater of two marshes were determinted, and meanwhile methane flux in the two marshes was also measured in situ. Last, the soil potential methane production rate was determined by anaerobic incubation experiments. The results showed that:(1)The range of concentrationes of porewater acetate in the S. alterniflora and C. malaccensis marshes were0.04-88.6μM and0.05-12.94μM, respectively; formic acis was0.17-36.2μM,0.08-13.51μM, respectively; dissolved methane was0.08-433.50μM,0.08-124.62μM, respectively; dissolved carbon dioxide was20.61-2608.15μM,17.04-124.62μM, respectively; sulfate was0.02-6.84mM,0.08-7.92mM, respectively.(2)There was a significantly positive correlation between dissolved carbon dioxide and dissolved methane, but a significantly negative correlation between dissolved methane and sulfate. There was significantly positive correlation between acetic and dissolved methane in the S. alterniflora marsh, In contrast,there was no correlation in C. malaccensis marsh.(3)Annual averaged methane emission in the S. alterniflora marsh was15.13mg·m-2·h-1, C. malaccensis was5.53mg·m-2·h-1, there is not a significant difference between the two marshes.(4)Annual average of soil potential methane production from the S. alterniflora marsh was0.0581μg·g-1·d-1, C. malaccensis was0.0129ug·g-1·d-1, there was a significant difference between the two marshes..