[Short-term Effects of Nitrogen and Sulfate Addition on CH and CO Emissions in the Tidal Marsh of Minjiang River Estuary].

In April 2015, using enclosed static opaque chamber-GC techniques, the short-term effects of nitrogen and sulfate addition on the CH and CO emissions were measured in the marsh in the high tidal flat of the Minjiang River estuary, and the key factors controlling the variation of CH and CO were examined. The influences of nitrogen and sulfate addition on the CH and CO emissions were different in different time scales. CH emission increased significantly under the NHCl (NH) and NHNO+KSO (NS) additions (<0.01), COemission increased significantly with NS addition (<0.05), but CH and CO emissions demonstrated an obvious fluctuation pattern with KNO (NO) and KSO(S) additions. Compared with the control (CK), average CH emissions increased by 286.36% and 122.73%, respectively, in the NH and NS addition treatments, average CO emissions increased by 39.92% and 34.24%, respectively, with the NH and NS additions treatments. The nitrogen and sulfate addition changed the temporal variation of CH and COemissions from the wetlands in growing season. Significant correlations were found among CO, CH emissions, and soil temperature, electrical conductivity (EC), DOC (dissolved organic carbon) and NH-N (<0.05 or <0.01) in the treatments with NH and NS additions; and soil temperature, EC, DOC and NO-N (<0.05 or <0.01) in the treatments with NO and NS additions. Temperature, EC and nitrogen availability were the dominant factors controlling the temporal variations of CH and COemissions in estuarine tidal marsh ecosystem.