The Characteristic Of Nutrients And Methane In Porewater In Minjiang River Estuary

Porewater equilibration samplers were used to obtain porewater inventories of inorganic nutrients(NH4+,NOx,PO43-), chloride(Cl-), sulfate(SO42-)and methane(CH4) in intertidal creek-bank sediments at nine sites of Phragmites astralis,Cyperus malaccensis Lam.var.brevifolius Bocklr and Spartina alterniflora in the Minjiang River estuary wetland. The seasonal dynamics of inorganic nutrients (NH4+, NOX, PO43-) concentrations was studied; the correlativity between nitrogen phosphorus was analyzed; and the correlation between methane flux and sulfate reduction was discussed. The results showed that the effect of different vegetation types on the physicochemical indexes of porewater was not apparent. The of CH4,SO42-,NO3-,NO2-,PO43- and Cl- in the porewater characterized by significant seasonal changes, except the NH4+ concentrations. No significant correlativity between nitrogen concentrations and phosphorus concentrations was found. The sulphate reducing bacteria was very active in sediments, so there occured strong sulphate reduction in the sediment. There existed no significant correlation between CH4 flux and sulphate concentrations.