狮子山矿区不同土地利用类型对土壤微生物群落多样性的影响

Effects of Different Land Use Types on Microbial Community Diversity in the Shizishan Mining Area

土壤微生物在生态系统功能中起着至关重要的作用,土壤微生物群落结构可由与采矿活动相关的矿山不同功能区域来反馈土壤中重金属污染现状.为研究铜陵狮子山矿区重金属污染对微生物群落结构的胁迫影响,在中国安徽狮子山矿区收集了4种不同土地利用类型(菜园、尾矿库、堆矿区和选矿区)的土壤.通过测量这4种不同土地利用类型的土壤理化性质和重金属含量,并利用Illumina MiSeq高通量测序技术,对本地土壤微生物群落丰度以及结构多样性进行了分析.结果表明,各区域理化性质差异显著,内梅罗综合污染指数依次为堆矿区(7. 28)>选矿区(6. 99)>尾矿库(6. 55)>菜园(5. 92).微生物群落丰度及结构多样性分布表现为尾矿库>选矿区>菜园>堆矿区.此外,PCo A、CCA和相关性分析表明,土地利用类型、土壤p H和重金属含量等相关参数对微生物群落有显著影响.优势土壤微生物群落在门(0. 01)水平上分别为Proteobacteria、Bacteroidetes、Acidobacteria和Actinobacteria,在纲水平上分别为β-Proteobacteria、α-Proteobacteria和γ-Proteobacteria,在属水平上分别为Flavobacterium、Kaistobacter和Ramlibacter.并得到对重金属较为耐受的菌群如Proteobacteria、Firmicutes、β-Proteobacteria和Kaistobacter等.这些结果加深了对重金属污染矿区土壤中微生物变化和聚集模式的认识,可为重金属矿区的生物修复提供菌种和理论依据.

Soil microorganisms play an important role in ecosystem function.Soil microbial community structure can be used to feed back the status of heavy metal pollution in soil at different functional areas of mines related to mining activities.Samples of four different land use types(vegetable garden,tailings reservoir,heap mining area,and dressing area)were collected in the Shizishan mining area,Tongling,Anhui Province,to determine the effect of heavy metal pollution on microbial community structure.Soil physical and chemical properties and heavy metal contents of the four different land use types were measured,and soil microbial community abundance and structure diversity were analyzed by Illumina MiSeq high-throughput sequencing technology.The results show that there are significant differences in physical and chemical properties between different regions.The comprehensive pollution index of Nemerow is heap mining area(7.28)>dressing area(6.99)>tailings reservoir(6.55)>vegetable garden(5.92).The distribution of microbial community abundance and structure diversity was tailings reservoir>dressing area>vegetable garden>heap mining area.In addition,principal coordinates analysis(PCoA),canonical correspondence analysis(CCA),and correlation analysis showed that land use type,soil pH and heavy metal content had significant effects on the microbial community.The dominant soil microbial communities at the phylum level were Proteobacteria,Bacteroidetes,Acidobacteria,and Actinobacteria,at the class level wereβ-Proteobacteria,α-Proteobacteria,andγ-Proteobacteria,and at the genus level were Flavobacterium,Kaistobacter,and Ramlibacter.The bacteria that are more tolerant to heavy metals are Proteobacteria,Firmicutes,β-Proteobacteria,and Kaistobacter.These results have deepened our understanding of microbial changes and aggregation patterns in soils of heavy-metal-contaminated mining areas.This study can provide bacterial species and theoretical basis for bioremediation of heavy metal mining areas.