滨海湿地互花米草入侵和治理后土壤碳氮磷生态化学计量比及固碳微生物特征OA

Spartina alterniflora invasion poses a threat to the ecological security of coastal wet-lands.By taking bare tidal flats,S.alterniflora-invaded wetland,and restored mangrove wetland after S.alterniflora control as research objects,this study explored the impacts of soil carbon(C),nitrogen(N),and phosphorus(P)and their stoichiometric ratios on soil carbon-sequestering microorganisms in typical coastal wetlands of Fujian Province.The results showed that:S.alterniflora invasion signifi-cantly increased soil organic carbon(SOC)content,C∶P ratio,and N∶P ratio by 15.30%,27.68%,and 23.87%,respectively(P<0.05).Compared with the S.alterniflora-invaded wetland,the soil C∶N∶P stoichiometric ratios in the mangrove wetland after restoration showed a further in-crease.Pseudomonadota was the dominant phylum of carbon-sequestering microorganisms across all habitats.At the genus level,Hyphomicrobium was the dominant genus in both bare tidal flat and S.alterniflora-invaded wetlands,while Herbaspirillum was the dominant genus in mangrove wetlands after restoration.Soil C,N,and P contents and their stoichiometric ratios exerted significant habitat-specific regulatory effects on the dominant carbon-sequestering genera,while carbon and nutrient conditions showed a selective screening effect on the community structure of carbon-sequestering mi-croorganisms.