Ecological Effects of Single-Walled Carbon Nanotubes on Soil Microbial Communities and Soil Fertility

The manufacturers of single-walled carbon nanotubes (SWCNTs) are continuously expanding their manufacturing and commercial markets, indicating that the environmental release and accumulation of SWCNTs in soil is inevitable. However, little is known about the effects of SWCNTs on soil physicochemical properties and soil microbial communities. Our results showed that treatment with SWCNTs resulted in an enhancement of microorganism metabolism related to soil organic compound degradation and a change in the structure of soil microbial communities, but the diversity of soil microorganisms was not significantly affected. The decrease in soil urease activity and the increase in the relative abundance of Nitrospirae after SWCNTs exposure might be relevant to the induction of soil nitrification. The relative abundances of phosphate-solubilizing microorganisms increased after exposure to SWCNTs, which was beneficial for phosphorus bioavailability in the soil. Our current study highlights that exposure to SWCNTs at concentrations of 3 and 10 mu g/g can change the composition of soil microorganism communities, promote soil organic degradation and improve soil fertility by enhancing N and P availability in a short time.