College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
Hunan Academy of Forestry, Hunan, 410004, China.
Sci Rep. 2019 Feb 13;9(1):1947. doi: 10.1038/s41598-018-38360-2.
Mining and smelting activities are the major sources of antimony (Sb) contamination. The soil around Xikuangshan (XKS), one of the largest Sb mines in the world, has been contaminated with high concentrations of Sb and other associated metals, and has attracted extensive scholarly attention. Phytoremediation is considered a promising method for removing heavy metals, and the diversity and structure of rhizosphere microorganisms may change during the phytoremediation process. The rhizosphere microbiome is involved in soil energy transfer, nutrient cycling, and resistance and detoxification of metal elements. Thus, changes in this microbiome are worthy of investigation using high-throughput sequencing techniques. Our study in Changlongjie and Lianmeng around XKS revealed that microbial diversity indices in the rhizospheres of Broussonetia papyrifera and Ligustrum lucidum were significantly higher than in bulk soil, indicating that plants affect microbial communities. Additionally, most of the bacteria that were enriched in the rhizosphere belonged to the Proteobacteria, Acidobacteria, Actinobacteria, and Bacteroidetes. In Changlongjie and Lianmeng, the diversity and abundance of the microbial community in the B. papyrifera rhizosphere were higher than in L. lucidum. In parallel, the soil pH of the B. papyrifera rhizosphere increased significantly in acidic soil and decreased significantly in near-neutral soil. Redundancy analyses indicated that pH was likely the main factor affecting the overall bacterial community compositions, followed by moisture content, Sb, arsenic (As), and chromium (Cr).
采矿和冶炼活动是锑（Sb）污染的主要来源。世界上最大的 Sb 矿之一——锡矿山（XKS）周围的土壤受到 Sb 和其他相关金属的高度污染，引起了广泛的关注。植物修复被认为是去除重金属的一种很有前途的方法，而根际微生物的多样性和结构可能会在植物修复过程中发生变化。根际微生物组参与土壤能量传递、养分循环以及对金属元素的抵抗和解毒。因此，使用高通量测序技术对这种微生物组的变化进行研究是值得的。我们在 XKS 周围的长龙界和联盟的研究表明，构树和女贞根际的微生物多样性指数明显高于体土，这表明植物会影响微生物群落。此外，根际中富集的大多数细菌属于变形菌门、酸杆菌门、放线菌门和拟杆菌门。在长龙界和联盟，构树根际微生物群落的多样性和丰度高于女贞。同时，在酸性土壤中，构树的根际土壤 pH 值显著升高，而在近中性土壤中则显著降低。冗余分析表明，pH 值可能是影响细菌群落组成的主要因素，其次是含水量、Sb、砷（As）和铬（Cr）。
