作 者：Chen, Y.P., Chen, G.C., Ye, Y.
影响因子：3.746
刊物名称：Science of the Total Environment
出版年份：2015
卷：526 页码：19–28
Soil properties and soil–atmosphere fluxes of CO2, CH4and N2O from four coastal wetlands were studied throughout the year, namely, nativeKandelia obovatamangrove forest vs. exoticSonneratia apetalamangrove forest, and nativeCyperus malaccensissalt marsh vs. exoticSpartina alterniflorasalt marsh. Soils of the four wetlands were all net sources of greenhouse gases whileSonneratiaforest contributed the most with a total soil–atmosphereCO2-equivalent flux of 137.27 mg CO2m−2h−1, which is 69.23%, 99.75% and 44.56% higher than that ofKandelia,CyperusandSpartina, respectively. The high underground biomass and distinctive root structure ofSonneratiamight be responsible for its high greenhouse gas emission from the soil. Soils inSpartinamarsh emitted the second largest amount of total greenhouse gases but it ranked first in emitting trace greenhouse gases. Annual average CH4and N2O fluxes fromSpartinasoil were 13.77 and 1.14 μmol m−2h−1, respectively, which are 2.08 and 1.46 times that ofKandelia, 1.03 and 1.15 times ofSonneratia, and 1.74 and 1.02 times ofCyperus, respectively.Spartinahas longer growing season and higher productivity than native marshes which might increase greenhouse gas emission in cold seasons. Exotic wetland soils had higher carbon stock as compared to their respective native counterparts but their carbon stocks were offset by a larger proportion because of their higher greenhouse gas emissions. Annual total soil–atmosphere fluxes of greenhouse gases reduced soil carbon burial benefits by 8.1%, 9.5%, 6.4% and 7.2% forKandelia,Sonneratia,CyperusandSpartina, respectively, which narrowed down the gaps in net soil carbon stock between native and exotic wetlands. The results indicated that the invasion of exotic wetland plants might convert local coastal soils into a considerable atmospheric source of greenhouse gases although they at the same time increase soil carbon accumulation.
Fig.4.Soil–atmosphere fluxes of N2O, CH4and CO2in different seasons of different vegetation types. Mean and standard deviation are shown. Different letters above the error bars in the same season indicate significant differences among the four vegetation types at p b 0.05 according to one-way ANOVA.
