Guo Ziwen, Yang Jiejie, Sarkodie Emmanuel Konadu, Li Kewei, Deng Yan, Meng Delong, Miao Bo, Liu Hongwei, Liang Yili, Yin Huaqun, Liu Xueduan, Jiang Luhua
School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China; Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China.
School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China; Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China.
Ecotoxicol Environ Saf. 2021 Nov 29;228:113037. doi: 10.1016/j.ecoenv.2021.113037.
Over the past few decades, nonferrous mining has produced numerous waste rock and part of the waste that has not been properly treated was generally dumped at roadsides and hill slopes. However, the vertical distributions of toxic metal(loid)s and composition of microbial communities in waste heap and the under-laid pristine soil are rarely studied. In this work, the fraction-related distributions of toxic metal(loid)s were investigated at a waste heap profile and the indigenous microbial assemblages were also analyzed by Illumina sequencing of 16 s rRNA genes. Results showed that compared to the under-laid pristine soil, content of toxic metal(loid)s, especially Cd, As and Pb, in waste rock layer were higher. Most of As in subsoil existed as non-specifically sorbed and specifically-sorbed fractions, which could be ascribed to the migration from the upper layer. The mobility was significantly correlated with Eh, EC, clay content, CEC and the total content of metal(loid)s. Phyla Proteobacteria, Acidobacteria and Firmicutes dominated the microbial communities. The microbial community compositions at the genus level were similar, but their relative abundances were mainly influenced by pH, CEC, Eh, SOM, and bioavailability content of toxic metal(loid)s. Besides, microbial functions of elements (S, Fe, Mn and As) oxidation/reduction and metabolites (siderophore, biosurfactant, organic acid, phosphatase and urease) potentially were used for pollutants bioremediation.
在过去几十年里，有色金属开采产生了大量废石，部分未经妥善处理的废弃物通常被倾倒在路边和山坡上。然而，废石堆及其下方原生土壤中有毒金属（类金属）的垂直分布和微生物群落组成却鲜有研究。在这项工作中，研究了废石堆剖面中有毒金属（类金属）的形态相关分布，并通过对16 s rRNA基因进行Illumina测序分析了原生微生物群落。结果表明，与下方原生土壤相比，废石层中有毒金属（类金属）的含量更高，尤其是镉、砷和铅。亚表层土壤中的大部分砷以非特异性吸附态和特异性吸附态存在，这可能归因于其从上层的迁移。迁移率与氧化还原电位、电导率、粘土含量、阳离子交换量和金属（类金属）总量显著相关。变形菌门、酸杆菌门和厚壁菌门在微生物群落中占主导地位。属水平上的微生物群落组成相似，但其相对丰度主要受pH值、阳离子交换量、氧化还原电位、土壤有机质和有毒金属（类金属）的生物有效性含量影响。此外，元素（硫、铁、锰和砷）氧化/还原以及代谢产物（铁载体、生物表面活性剂、有机酸、磷酸酶和脲酶）的微生物功能可能用于污染物的生物修复。
