FeO nanoparticles affect paddy soil microbial-driven carbon and nitrogen processes: roles of surface coating and soil types

• Published in: Environmental science. Nano Vol. 9; no. 7; pp. 244 - 2452
• Main Authors: Xu, Jiangbing, Chen, Yaqian, Luo, Jingyi, Xu, Jiatong, Zhou, Guoyi, Yu, Yingliang, Xue, Lihong, Yang, Linzhang, He, Shiying
• Format: Journal Article
• Published: 14.07.2022
• ISSN: 2051-8153; 2051-8161
• DOI: 10.1039/d1en01177d

Magnetic Fe 3 O 4 nanoparticles (nFe 3 O 4 ) are the most widely used nanomaterials and are inevitably introduced to soils. To overcome particle agglomeration, nFe 3 O 4 are often coated with protective agents. However, scarce information has addressed the impacts of surface coating of nFe 3 O 4 on biochemical processes and microbial properties in soil. In this study, a laboratory incubation experiment was employed to reveal the response of gas production, mineral N content, enzymatic activities and soil bacterial community to nFe 3 O 4 and meso -2,3-dimercaptosuccinic acid coated nFe 3 O 4 (nFe 3 O 4 @DMSA) in three representative paddy soils in China, i.e. lateritic soil (LS), Wushan soil (WS), and red soil (RS). The results showed that nFe 3 O 4 @DMSA, rather than nFe 3 O 4 , influenced these parameters profoundly, with varying effects in the soil types. Specifically, in RS nFe 3 O 4 @DMSA, rather than nFe 3 O 4 , promoted the CH 4 production, soil NH 4 -N concentration, and soil enzymatic activities of β-xylanase (BX) and β- N -acetylglucosaminidase (NAG), but decreased the CO 2 production and β-glucosidase (BG) activity. By contrast, in LS and WS nFe 3 O 4 @DMSA led to increases in CO 2 emission, soil NH 4 -N content, and BG, BX, and NAG activities, but a decrease in CH 4 production. Data from 16S rRNA gene sequencing showed the varying responses to the nanoparticles in terms of soil bacterial taxa and putative functional groups. The methanogens and the N-fixation group had strong affinities with the CH 4 production and NH 4 -N content, respectively. Geobacter was closely related to the CH 4 production in all soils. Anaeromyxobacter , Azospirillum , and Burkholderia - Caballeronia - Paraburkholderia had close relationships with the N-fixation group/NH 4 -N content in LS, WS and RS, respectively. Collectively, nFe 3 O 4 @DMSA changed the microbial-driven biochemical process in the soils, depending on the soil types. Caution should be paid to the complex interaction between the soil matrix and nanoparticle types for better management of nanoparticles in future. nFe 3 O 4 @DMSA, rather than nFe 3 O 4 , greatly influenced the microbial-driven element cycling, and the effect varied with soil types.