摘要
An understanding of soil microbial communities is crucial in roadside soil environmental assessments.The 16S rRNA se quencing of a stressed microbial community in soil adjacent to the Qinghai-Tibet Highway(QTH)revealed that the accu mulation of heavy metals(over about 10 years)has affected the diversity of bacterial abundance and microbial community structure.The proximity of a sampling site to the QTH/Qinghai-Tibet Railway(QTR),which is effectively a measure of the density of human engineering,was the dominant factor influencing bacterial community diversity.The diversity of bacterial communities shows that 16S rRNA gene abundance decreased in relation to proximity to the QTH and QTR in both alpine wetland and meadow areas.The dominant phyla across all samples were Actinobacteria and Proteobacteria.The concentration of Cr and Cd in the soil were positively correlated with proximity to the QTH and QTR(MC/WC sam pling sites),and Ni,Co,and V were positively correlated with proximity to the QTH and QTR(MA/WA sampling sites).The results presented in this study provide an insight into the relationships among heavy metals and soil microbial commu nities,and have important implications for assessing and predicting the impacts of human-induced activities from the QTH and QTR in such an extreme and fragile environment.
An understanding of soil microbial communities is crucial in roadside soil environmental assessments. The 16 S rRNA sequencing of a stressed microbial community in soil adjacent to the Qinghai-Tibet Highway(QTH) revealed that the accumulation of heavy metals(over about 10 years) has affected the diversity of bacterial abundance and microbial community structure. The proximity of a sampling site to the QTH/Qinghai-Tibet Railway(QTR), which is effectively a measure of the density of human engineering, was the dominant factor influencing bacterial community diversity. The diversity of bacterial communities shows that 16 S rRNA gene abundance decreased in relation to proximity to the QTH and QTR in both alpine wetland and meadow areas. The dominant phyla across all samples were Actinobacteria and Proteobacteria.The concentration of Cr and Cd in the soil were positively correlated with proximity to the QTH and QTR(MC/WC sampling sites), and Ni, Co, and V were positively correlated with proximity to the QTH and QTR(MA/WA sampling sites).The results presented in this study provide an insight into the relationships among heavy metals and soil microbial communities, and have important implications for assessing and predicting the impacts of human-induced activities from the QTH and QTR in such an extreme and fragile environment.
基金
funded by a grant from the Cold and Arid Regions Environmental and the Engineering Research Institute of the Chinese Academy of Sciences Nos. HHS-TSS-STS-1505 and 55Y855Z11, CAS "Light of West China" Program, Frontier Science Research Program of Chineses Academy of Scienc No. QYZDJ- SSW_SMC011
