In recent years, the research about sulfur gases emission in global ecosystems, particularly in wetland systems, is the hot spots in the fields of global change. Biological invasion is the major part of global change. Spartina alterniflora is one of the rare exotic species which can release sulfur-contained gas such as H₂S and DMS. It is helpful and significant to discover the mechanisms and impacts of S. alterniflora invasion and the feedback of wetlands on global change by studying on sulfur and sulfur-contained gas. At the same time, as the common disturbing agents in wetland systems, clipping, tidewater and crab burrowing may have a certain impact on sulfur gases emission of entire wetland system. Therefore, we discussed the effects of these three factors on the H₂S emission of the S. alterniflora marsh in Yancheng. Main results are listed below:

(1) Clipping and crab burrowing can significantly increase H₂S emission flux in the Spartina alterniflora marsh. Although the tidal flow can also enhance its flux, it doesn’t reach the significant level.

(2) In the S. alterniflora marsh, H₂S gas is released from the underground part which is the soil including roots of S. alterniflora. It doesn’t concern with the aboveground part.

(3) In addition, the aerenchyma system of S. alterniflora can supply a pathway for H₂S emission from underground to aboveground.