Zhang Jianchao, Xiao Jian, Li Siliang, Ran Wei
Institute of the Surface-Earth System Science Research, Tianjin University, Tianjin, 300072, China.
Jiangsu Provincial Coordinated Research Center for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China.
Sci Rep. 2017 Oct 27;7(1):14256. doi: 10.1038/s41598-017-14445-2.
Natural nanoparticles are of central importance in the environment, e.g. sorption of soil organic carbon (SOC) and contaminants. A large number of study have focused on the metal binding, transport and ecotoxicity of nanoparticles. Fertilizer amendments are routinely applied to arable soils and induce changes in soil chemical, physical and biological properties. However, the effects of fertilizer amendments on natural nanoparticles are still unknown. In this study, soil nanoparticles were separated from acid red soil (Ferralic Cambisol) including long-term (26 years) treatments of unfertilized control (CK), chemical nitrogen, phosphorus and potassium fertilizers (NPK) and raw pig manure (M). The results from high-resolution transmission electron microscopy (HRTEM) and Fourier-transformed infrared (FTIR) spectroscopy indicated that nanoparticles in red soil were heterogeneous organo-mineral associations with irregular shapes, regardless of fertilization history. In addition, kaolinite and allophane occurred in the soil nanoparticles. Intriguingly, we found the content of allophane under M treatment (0.64 g kg) was much higher than under CK and NPK treatments. However, the CK (0.27 g kg) and NPK (0.21 g kg) had similar allophane concentrations. Our study may indicate long-term organic manure amendment initializes positive feedback loop for further SOC sequestration. However, the mechanisms for the enhancement of nanomineral allophane by manure amendment deserve further investigation.
天然纳米颗粒在环境中至关重要，例如对土壤有机碳（SOC）和污染物的吸附作用。大量研究聚焦于纳米颗粒的金属结合、迁移及生态毒性。肥料改良剂常规施用于耕地土壤，会引起土壤化学、物理和生物学性质的变化。然而，肥料改良剂对天然纳米颗粒的影响仍不清楚。在本研究中，从酸性红壤（铁铝土）中分离出土壤纳米颗粒，该红壤包括长期（26年）未施肥对照（CK）、化学氮磷钾肥（NPK）和生猪粪肥（M）处理。高分辨率透射电子显微镜（HRTEM）和傅里叶变换红外（FTIR）光谱分析结果表明，无论施肥历史如何，红壤中的纳米颗粒都是形状不规则的异质有机-矿物结合体。此外，土壤纳米颗粒中存在高岭石和水铝英石。有趣的是，我们发现M处理下的水铝英石含量（0.64 g/kg）远高于CK和NPK处理。然而，CK（0.27 g/kg）和NPK（0.21 g/kg）的水铝英石浓度相似。我们的研究可能表明长期施用有机肥会启动一个正反馈循环，以进一步固存SOC。然而，有机肥改良提高纳米矿物水铝英石含量的机制值得进一步研究。
