Reduction in Hg phytoavailability in soil using Hg-volatilizing bacteria and biochar and the response of the native bacterial community
Reduction in Hg phytoavailability in soil using Hg-volatilizing bacteria and biochar and the response of the native bacterial community
复制标题
使用汞挥发细菌和生物炭降低土壤中汞植物有效性以及本地细菌群落的反应
DOI：
10.1111/1751-7915.13457
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发表时间：
2019
影响因子：
5.7
通讯作者：
Chen Jinquan
中科院分区：
文献类型：
--
作者：
Chang Junjun;Yang Qingchen;Dong Jia;Ji Bohua;Si Guangzheng;He Fang;Li Benyan;Chen Jinquan
生物方法被认为是修复土壤汞污染的有前途的、生态友好的策略。本研究考察了两种“绿色”添加剂--汞挥发细菌(Pseudomonassp.DC-B1和芽孢杆菌属(Bacillussp.)DC-B2)和木屑生物炭及其组合降低土壤中汞(II)的植物有效性以及添加剂对土壤细菌群落的影响。结果表明，与不加添加剂的对照相比，土壤、生菜地上部和根中汞含量均有不同程度的降低，培养56d的降幅分别为12.3~27.4%、24.8~57.8%和2.0~48.6%。DC-B2与4%生物炭配合使用对降低生菜地上部汞含量效果最好，比对照降低了57.8%。焦解测序分析表明，不同处理下土壤中细菌群落的总体组成相似，尽管优势属的相对丰度随着添加剂的变化而发生变化，表明添加剂对土壤微生物生态系统的影响相对较弱。在实验结束时，假单胞菌和芽孢杆菌的相对丰度较低，接近本底水平，表明外源细菌对当地微生物生态位的生物干扰很小。
Biological approaches are considered promising and eco‐friendly strategies to remediate Hg contamination in soil. This study investigated the potential of two ‘green’ additives, Hg‐volatilizing bacteria (Pseudomonassp. DC‐B1 andBacillussp. DC‐B2) and sawdust biochar, and their combination to reduce Hg(II) phytoavailability in soil and the effect of the additives on the soil bacterial community. The results showed that the Hg(II) contents in soils and lettuce shoots and roots were all reduced with these additives, achieving more declines of 12.3–27.4%, 24.8–57.8% and 2.0–48.6%, respectively, within 56 days of incubation compared to the control with no additive. The combination of DC‐B2 and 4% biochar performed best in reducing Hg(II) contents in lettuce shoots, achieving a decrease of 57.8% compared with the control. Pyrosequencing analysis showed that the overall bacterial community compositions in the soil samples were similar under different treatments, despite the fact that the relative abundance of dominant genera altered with the additives, suggesting a relatively weak impact of the additives on the soil microbial ecosystem. The low relative abundances ofPseudomonasandBacillus, close to the background levels, at the end of the experiment indicated a small biological disturbance of the local microbial niche by the exogenous bacteria.