摘要
With the ongoing commercialization of nanotechnology products, the increasing use of engineered nanoparticles (NPs) could lead potentially to environmental risks. This study investigated the dynamic influences of three iron-based NPs (Fe-0, Fe3O4, and Fe2O3) applied into a red soil (RS) and a Wushan soil (WS) with different application rates (2 to 6 g kg(-1)) on soil physicochemical properties such as pH, dissolved organic carbon (DOC), available ammonium nitrogen (NH4+-N), available phosphorus (AP), and enzymatic activities. The results showed that the addition of Fe-0 NPs increased DOC and available NH4+-N, but significantly decreased AP, while Fe3O4 and Fe2O3 NPs slightly reduced soil pH in both soils and significantly declined available NH4+-N in the WS and AP in the RS. No significant difference was observed between the effects of Fe3O4 and Fe2O3 NPs on soil properties except AP in the RS. All iron-based NPs decreased the activities of urease and acid phosphatase in both soils. The effects on soil physicochemical properties, especially available NH4+-N and AP induced by iron-based NPs, varied greatly with soil types. These results implied that cautions should be paid for the environmental application of iron-based NPs, especially iron oxide NPs in soils.
- 单位