Comparison And Mechanism Anslysis On Soil Methane Production Rates In Different Marshes Zones In The Min Rever Estuary

The Minjiang River Estuary wetland is one of the most representative and typical estuarine tidal wetlands in southeast seashore of China. Phragmites australis and Cyperus malaccensis (common reed) are the two main native dominant species, and Spartina alterniflora is an invasive plant. Methane production rates in different marshes soil in the Minjiang River estuary wetland were measured using laboratory incubation. The spatial heterogeneity of soil methane production rates were discussed, as well as the role of contents of methane production rates substrate and electronic receptors as the relevant factors. The results showed that:(1) The range of methane production rates in three kinds of plant marsh soil were respectively between0.0135-0.4128μg·g-1·-1,0.0204-0.0781μ-·g-1·d-1and0.0253-0.0913μg·g·d-1; the average methane production rates was respectively0.1420μg·g-1·d-1,0.0584μg·g-1·d-1and0.0668μg·g-1·d-1.(2) As a whole, substrates in three kinds of plant marsh soil, acetate had a very significant positive correlation with the methane production rates; carbon dioxide and DMS had no significant correlation with methane production rates.(3) Electronic receptors in three kinds of plant marsh soil, SO42-, NO3-and Fe3+have no significant correlation with methane production rates.(4) Microorganism in three kinds of plant marsh soil, MA had a very significant positive correlation with the methane production rates; SRB number had no significant correlation with methane production rates.(5) Physical and chemical factors in three kinds of plant marsh soil, water content and viscous grain had a significant positive correlation with the methane production rates; DOC, TN, pH value, salinity and soil temperature (0-10cm) had no significant correlation with methane production rates.