Soil bacterial communities respond differently to graphene oxide and reduced graphene oxide after 90 days of exposure

Graphene-based nanomaterials (GBNs) are likely to be entering the soil environment in increasing amounts via consumer products. However, the disturbance of bacterial communities and their associated ecological functions by GBNs remains elusive. We performed a soil incubation experiment with the addition of graphene oxide (GO) and reduced graphene oxide (RGO). The Illumina sequencing technique was used to investigate changes in bacterial communities, and the functional groups of the communities were analyzed using the functional annotation of prokaryotic taxa database. After 90 days of exposure, RGO induced a lower bacterial richness than GO. However, GO induced larger changes in community composition and functions than RGO. After exposure to GBNs, some of the functional groups associated with organic matter degradation and biogeochemical cycling of nitrogen and sulfur decreased. However, the functional group associated with aromatic compound degradation increased, possibly because GBNs contain rich aromatic hydrocarbon structures, which are tolerated by this functional group.