Study On Methane Production And Oxidation Potential Of Phragmites Australis Marsh Soil In Minjiang River Estuary

The Minjiang River estuarine saltmarsh is one of the most representative subtropical estuarine saltmarshes in southeast coast of China. Phragmites australis is the dominant plant of this wet land. By using indoor culture method, the author researches the soil methane of the Minjiang River estuarine saltmarsh, and attempt to find the temporal and spatial variation of its productive potential and Oxidation potential, and also attempt to find the fact of influence about the variation. The final conclusions are as follows:(1) With the extension of the incubation time, the methane production potential presents a trend of after rising to drop, it changes from0.009μg/g·d to0.325μg/g·d and the maximum is at0-5cm soil layer; the tendency of methane oxidation potential is fluctuating decline, it changes from0.282μg/g·d to7.824μg/g·d and the maximum is at5-15cm soil layer.(2) We add methanol, acetic acid, methylamine, trimethylamine and H2/CO2to the soil samples respectively. And find all of them can enhance the methane’s production potential, with different degree, and the order is trimethylamine>methanol>acetic acid>H2/CO2; but as to the inhibitory action to the methane oxidation potential, the order is methanol>trimethylamine>acetic acid.(3) The electron acceptors’influence to the potential of the methane production and oxidation in Minjiang River estuary saltmarsh is that both the potential of the methane production and oxidation have a non significant relation to four price manganese, nitrate radical, nitrite ion, ferric ion and sulfate ion.(4) By using the Q10value to characterize the potential of methane production and oxidation’s reaction to temperature. We find that the average Q10of methane production potential is2.56, and the average Q10of methane oxidation potential is1.21. The methane production potential is more sensitive to temperature than the methane oxidation potential in the Minjiang River estuarine phragmites saltmarsh.The research results enrich the basic science information of the research about methane production and oxidation in the estuarine saltmarsh in our country, which has a significant value of academic and practical application.