Response of soil enzyme activity and bacterial community to black phosphorus nanosheets†
Currently, black phosphorus (BP) is widely applied in a variety of fields. Concerning the potential toxicity of BP nanosheets towards mammalian cells and bacteria, there is a great need to evaluate their ecological effects. This study was focused on the effect of BP nanosheets on enzyme activity, bacterial community structure, and bacterial function of black soil and burozem. We found BP nanosheets had no significant impact on enzyme activities in black soil during the 60 day exposure. In contrast, the activities of urease and catalase in burozem were significantly inhibited at day 10 and day 30, respectively, which were gradually recovered at day 60. The introduction of BP nanosheets significantly decreased the community richness in burozem at day 10, but had no effect either on the diversity or the richness in black soil. The discrepancies were attributed to the stronger interaction of BP nanosheets with organic matter-rich black soil, leading to a lowered bioavailability of BP nanosheets. Nevertheless, BP nanosheets were predicted to have negligible effect on bacterial function in both soils. It is worthwhile to further investigate the in-depth mechanisms and dose-dependent effect in order to lay the foundation for safe application and discharge of BP nanosheets.