Nano-sized Fe2O3/Fe3O4 facilitate anaerobic transformation of hexavalent chromium in soil–water systems
Nano-sized Fe2O3/Fe3O4 facilitate anaerobic transformation of hexavalent chromium in soil–water systems
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纳米 Fe2O3/Fe3O4 促进土壤-水系统中六价铬的厌氧转化
DOI：
10.1016/j.jes.2017.01.007
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发表时间：
2017
影响因子：
6.9
通讯作者：
Qingbiao Li
中科院分区：
文献类型：
--
作者：
Yaxian Zhang;Hua Li;Libo Gong;Guowen Dong;Liang Shen;Yuanpeng Wang;Qingbiao Li
研究了纳米级和亚微米级Fe 2 O3/Fe 3 O 4对Cr（VI）生物还原的影响，并评价了纳米级Fe 2 O3/Fe 3 O 4对厌氧淹水土壤微生物群落的影响。结果表明，添加纳米Fe 2 O3和Fe 3 O 4的生物土样在21 d内Cr（VI）释放量净减少（317.1 ± 2.1 mg/L和324.0 ± 22.2 mg/L），约为空白对照Cr（VI）释放量（117.1 ± 5.6 mg/L）的2倍。此外，变性梯度凝胶电泳（DGGE）和高通量测序结果表明，添加纳米Fe 2 O3/Fe 3 O 4的土壤微生物群落中的微生物种类比对照组多。其中变形杆菌在铬污染土壤土著微生物群落中占绝对优势。此外，纳米Fe 2 O3/Fe 3 O 4对可溶性Cr（VI）的吸附主要是由于其部分降低了可溶性Cr（VI）的含量。因此，纳米Fe 2 O3/Fe 3 O 4的存在可以很大程度上促进Cr（VI）从淹水土壤中通过吸附和生物介导过程的活化和生物转化。
The purpose of this study is to investigate the effects of nano-sized or submicro Fe2O3/Fe3O4on the bioreduction of hexavalent chromium (Cr(VI)) and to evaluate the effects of nano-sized Fe2O3/Fe3O4on the microbial communities from the anaerobic flooding soil. The results indicated that the net decreases upon Cr(VI) concentration from biotic soil samples amended with nano-sized Fe2O3(317.1 ± 2.1 mg/L) and Fe3O4(324.0 ± 22.2 mg/L) within 21 days, which were approximately 2-fold of Cr(VI) concentration released from blank control assays (117.1 ± 5.6 mg/L). Furthermore, the results of denaturing gradient gel electrophoresis (DGGE) and high-throughput sequencing indicated a greater variety of microbes within the microbial community in amendments with nano-sized Fe2O3/Fe3O4than the control assays. Especially,Proteobacteriaoccupied a predominant status on the phylum level within the indigenous microbial communities from chromium-contaminated soils. Besides, some partial decrease of soluble Cr(VI) in abiotic nano-sized Fe2O3/Fe3O4amendments was responsible for the adsorption of nano-sized Fe2O3/Fe3O4to soluble Cr(VI). Hence, the presence of nano-sized Fe2O3/Fe3O4could largely facilitate the mobilization and biotransformation of Cr(VI) from flooding soils by adsorption and bio-mediated processes.