Change of fungal community structure in fluvo-aquic soil under different CO2 concentrations
Agricultural production is influenced by atmospheric CO2 concentration.Fungi are the key promoters of organic matter degradation and nutrient cycling in soil,but their responses to the increase of CO2 concentration are not clear.Miseq high-throughput sequencing technology was used to investigate the fungal community structure under four CO2 concentrations(ambient,2％,4％,6％)in microcosm experiments on typical fluvo-aquic soil in North China Plain.The results showed that fungal α diversity decreased significantly at 4％and 6％CO2 concentra-tion.Ascomycota,Basidiomycota,Mortierellomycota dominated the fungal community.The relative abundance of Basidiomycota and Glomeromycota decreased with the increases of CO2 concentration,while that of Ascomycota in-creased.The dominant genera included Mortierella,Fusarium,Citripora,Stachybotrys,and Humicola.The relative abundance of Citripora decreased with the increases of CO2 concentration,but that of Mortierella increased twofold in the condition of 2％CO2 concentration.CO2 concentration positively correlated with the relative abundance of Hu-micola phialophoroides and Sarocladium hominis,but negatively correlated with the relative abundance of Citripora afrocitrina.The fungal network topology in 2％CO2 treatment was similar to the control,but with more edges.The network topology changed obviously in 4％and 6％CO2 treatments,differentiating into two network modules.The keystone taxa were Aspergillus terreus,Trichoderma yunnanense,and Spizellomyces sp.This study clarified the response of fungi to different CO2 concentrations in fluvo-aquic soil,and provided theoretical reference for studying the impacts of elevated CO2 on ecosystem functions of farmland.
CO2 concentrationsoil fungicommunity compositionnetwork structure
万方数据
