Abstract:The carbon cycling process in wetland ecosystems has an important impact on global climate change.In this study,we used the GeoChip technology to detect the key functional genes of soil carbon cycle in the wetland soil of Chongming Dongtan,China.We also studied the effects of experimental warming and Spartina alterniflora invasion on carbon cycle of wetland soil and their relationships with environmental factors.The results showed that:1) the number and abundance of functional genes in soil carbon cycle were higher than those in other categories;2) the signal intensity of functional soil carbon cycle genes was higher in S.alterniflora community than in Phragmites australis community with the same temperature treatment;3) warming significantly reduced the signal intensity of most functional genes in soil carbon cycle,including the basic processes of carbon degradation,carbon fixation,and methane metabolism,but the influence was not significant for the S.alterniflora invasion and its interaction with warming (P>0.05);4) compared with the control,warming significantly reduced the abundance of functional genes of carbon cycle in the P.australis community,mainly including cda,exopolygalacturonase_fungi,rgh,xyla,xylanase,cellobiase and endoglucanase genes in the carbon degradation process and rubisco genes related to Calvin cycle during carbon fixation (P<0.01),but the changes were not significant in the S.alterniflora community and their mixed community (P>0.05);5) soil microbial carbon cycle functional genes were significantly and negatively correlated with soil reactive nitrogen gas emission and soil pH (P<0.05).In conclusion,warming significantly changes the functional gene abundances of soil carbon cycle.The research results provide data support for quantifying the impact of global warming on wetland carbon cycle and greenhouse gas emissions,and realizing carbon neutralization,and also provide scientific basis for the protection and management of wetland ecosystem.