Dynamics Of Porewater Dimethyl Sulfide,Methane Emission And Production In The Marshes In The Min River Estuary

From November,2011to October,2012, vertical patterns and temporal variations of the Dimethyl sulfide concentrations in the soil porewater (0～25cm) of the Spartina alterniflora marsh and Cyperus malaccensis marsh in the Shanyutan wetland were determinted. Meanwhile, monthly variations of methane flux was measured usingthe enclosed chamber+Gas chromatographic method. Methane production rates in different marshes soil (0-25cm) in the Min river estuary wetland were also measured with laboratory incubation.The results showed that:(1)The range of concentrationes of porewater dimethyl sulfide in the S. alterniflora marsh was3.62nmol·L-1～260.29nmol·L-1, annual mean average value was48.77nmol·L-1. The range in the C. malaccensis marsh was1.86nmol·L-1～188.20nmol·L-annual average value was34.90nmol·L-1.(2) There was no significant change in the porewater dimethyl sulfide concentrations among different soil layers in the S. alterniflora Marsh. The porewater dimethyl sulfide concentrations in the C. malaccensis marsh showed a gradually increasing trend from the surface layer to the bottom layer. Porewater dimethyl sulfide concentrations the S. alterniflora marsh was significant higher than that in the C. malaccensis marsh.(3) The range of methane emission in the S. alterniflora marsh was7.50mg·m-2·h-1～30.69mg·m-2·h-1, annual mean value was15.13mg·m-2·h-1. The range in the C malaccensis marsh was1.08mg·m-2·h-1～10.49mg·m-2·h-1, annual mean value was5.53mg·m-2·h-1.(4) The range of soil potential methane production from the S. alterniflora marsh was0.07ug·g-1-d-1～0.94ug·g-1·d-1, annual mean value was0.51ug·g-1·d-1. The range soil potential methane production from the C. malaccensis marsh was0.01ug·g-1·d-1～0.18ug·g-1·d-1, annual mean value was0.07ug·g-1·d-1(5) In the annual scale, There was no significantly correlation between methane emission and porewater dimethyl sulfide concentrations in the two marshes.