Periphytic biofilms accumulate manganese, intercepting its emigration from paddy soil

JOURNAL OF HAZARDOUS MATERIALS

卷:411

Article

Sun, Pengfei¹  Gao, Mengning¹  Sun, Rui¹  Wu, Yonghong^1,2  Dolfing, Jan³ 

[1] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Zigui Ecol Stn Three Gorges Dam Project, 71 East Beijing Rd, Nanjing 210008, Peoples R China

[2] China Three Gorges Univ, Coll Hydraul & Environm Engn, Yichang 443002, Hubei, Peoples R China

[3] Northumbria Univ, Fac Energy & Environm, Newcastle Upon Tyne NE1 8QH, Tyne & Wear, England

关键词: Periphytic biofilm;    Mn bio-accumulation;    Mn interception;    Driving factors;    Accumulation mechanisms;   

DOI  :  10.1016/j.jhazmat.2021.125172

来源: Elsevier

【 摘 要 】

Manganese (Mn) in acidic paddy soil has large potential in emigrating from the soil and pollute adjacent ecosystems. Single microorganisms modulate the biogeochemistry process of Mn via redox reactions, while the roles of microbial aggregates (e.g. periphytic biofilm) in modulating its biogeochemical cycle is poorly constrained. Here we collected a series of periphytic biofilms from acidic paddy fields in China to explore how periphytic biofilm regulates Mn behavior in paddy fields. We found that periphytic biofilms have large Mn accumulation potential: Mn contents in periphytic biofilm ranged from 176 ? 38 to 797 ? 271 mg/kg, which were 1.2?4.5 folds higher than that in the corresponding soils. Field experiments verified the Mn accumulation potential, underlining the biofilms function as natural barriers to intercept Mn emigrating from soil. Extracellular polymeric substances, especially the protein component, mediated adsorption was the main mechanism behind Mn accumulation by periphytic biofilm. Microorganisms in periphytic biofilms in general appeared to have inhibitory effects on Mn accumulation. Climatic conditions and nutrients in floodwater and soil affect the microorganisms, thus indirectly affecting Mn accumulation in periphytic biofilms. This study provides quantitative information on the extent to which microbial aggregates modulate the biogeochemistry of Mn in paddy fields.

【 授权许可】

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