Xu Hongyang, Fu Bingqing, Lei Jiaqi, Kang Hui, Wang Jun, Huang Xinhao, Zhu Fan
College of Horticulture, Hunan Agricultural University, Changsha, 410128, People's Republic of China.
College of Life Science and Technology, Central-South, University of Forestry and Technology, Changsha, 410004, People's Republic of China.
Environ Sci Pollut Res Int. 2023 Feb;30(10):26687-26702. doi: 10.1007/s11356-022-23962-1. Epub 2022 Nov 12.
Mining causes extreme heavy metal (HM) contamination to surrounding environments and poses threats to soil microbial community. The effects of HMs on soil microbial communities are not only related to their total amounts but also associated with the distribution of chemical fractions. However, the effects of chemical fractions on soil microbes and their interactions remain largely unclear. Here we investigated soil physicochemical properties and bacterial and fungal communities of soil samples from the control area and lightly (L), moderately (M), and heavily (H) contaminated areas, respectively, which were collected from long-term Pb-Zn slag contamination area in the southern China. The results showed that bacterial and fungal community composition and structure were significantly affected by HMs, while community diversity was not significantly affected by HMs. The critical environmental factor affecting bacterial and fungal communities was pH, and the impacts of chemical fractions on their changes were more significant than the total amounts of HMs. Variance partitioning analysis (VPA) revealed fungal community changes were mostly driven by HM total amounts, but bacterial community changes were mostly driven by soil chemical properties. Co-occurrence network indicated that interactions among species of fungal network were sparser than that of bacterial network, but fungal network was more stable, due to a more significant number of keystone taxa and a lower percentage of positive associations. These illustrated that the fungal community might serve as indicator taxa for HM-contaminated status, and specific HM-responsive fungal species such as Triangularia mangenotii, Saitozyma podzolica, and Cladosporium endophytica, and genus Rhizophagus can be considered relevant bioindicators due to their less relative abundance in contaminated areas. Additionally, HM-responsive bacterial OTUs representing five genera within Sulfurifustis, Thiobacillus, Sphingomonas, Qipengyuania, and Sulfurirhabdus were found to be tolerant to HM stress due to their high relative abundance in contaminated levels.
采矿导致周边环境受到极端重金属（HM）污染，并对土壤微生物群落构成威胁。重金属对土壤微生物群落的影响不仅与其总量有关，还与化学形态的分布有关。然而，化学形态对土壤微生物的影响及其相互作用在很大程度上仍不清楚。在此，我们分别调查了来自中国南方长期铅锌矿渣污染区的对照区、轻度（L）、中度（M）和重度（H）污染区土壤样品的理化性质以及细菌和真菌群落。结果表明，重金属显著影响细菌和真菌群落的组成与结构，而群落多样性未受到重金属的显著影响。影响细菌和真菌群落的关键环境因素是pH值，化学形态对其变化的影响比重金属总量更为显著。方差分解分析（VPA）表明，真菌群落变化主要由重金属总量驱动，而细菌群落变化主要由土壤化学性质驱动。共现网络表明，真菌网络中物种间的相互作用比细菌网络更为稀疏，但真菌网络更稳定，这是因为其关键分类群数量更多且正相关比例更低。这些结果表明，真菌群落可能作为重金属污染状况的指示分类群，三角孢属（Triangularia mangenotii）、Podzolic赛多孢属（Saitozyma podzolica）、内生枝孢属（Cladosporium endophytica）等特定重金属响应真菌物种以及根内球囊霉属（Rhizophagus）因其在污染区域相对丰度较低，可被视为相关生物指示物。此外，代表硫富杆菌属（Sulfurifustis）、硫杆菌属（Thiobacillus）、鞘氨醇单胞菌属（Sphingomonas）、奇氏原菌属（Qipengyuania）和硫红杆菌属（Sulfurirhabdus）五个属的重金属响应细菌操作分类单元，因其在污染水平下相对丰度较高，被发现对重金属胁迫具有耐受性。
