Characteristics Of Methane Emission From Invasive Species(Spartina Alterniflora) In Estuary Wetland Of The Min River

Exotic species Spartina alterniflora invaded the estuaries and coastal marshes, east of China. It distributed across nearly 22 latitudes from the Dianbai in south of Guangdong Province to the Panjin of Liaoning Province. The invasion of Spartina alterniflora has brought lots of bad influences to the biodiversity, ecosystem structure and function. Min River estuary is a typical open tidal estuary in the southeast coastal zone, China, Spartina alterniflora invaded rapidly over the past 3-4 years. The enclosed chamber technique was used to measure seasonal and diel patterns of methane flux during three stages (before flood, in tidal process and after ebb) from the Spartina alterniflora invasive patches in the Shanyutan wetland which is the biggest wetland in the Min River estuary region. In particular, the seasonal changes of methane fluxes to atmosphere and .hydrospere in the tidal process were firstly measured. Daily variation of methane emission from Spartina alterniflora was also measured in the summer and winter. The methane fluxes from Spartina alterniflora and local indigenous species Phragmites australis was compared. The result indicated that the Spartina alterniflora had the highest average methane emissions flux in autumn(September and October). Spartina alterniflora has the greater methane emission before flooding and after ebbing than that in the tidal process. The methane emissions flux from Spartina alterniflora was greater than that of the Phragmites australis wetland.