Ke Tiantian, Zhang Di, Guo Huaming, Xiu Wei, Zhao Yi
Ministry of Education, Key Laboratory of Groundwater Circulation and Environmental Evolution, School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Beijing), Beijing, China.
Ministry of Education, Key Laboratory of Groundwater Circulation and Environmental Evolution, School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Beijing), Beijing, China.
Sci Total Environ. 2022 Dec 15;852:158549. doi: 10.1016/j.scitotenv.2022.158549. Epub 2022 Sep 6.
High arsenic (As) in groundwater is an environmental issue of global concern, which is closely related to microbe-mediated As biogeochemical cycling. However, the distribution of genes related to As cycling and underlying microbial As biogeochemical processes in high As groundwater remain elusive. Hence, we profiled the As cycling genes (arsC, arrA, and aioA genes) and indigenous microbial communities in groundwater from a typical high As area, the Hetao Basin from China, using amplicon sequencing and qPCR techniques. Here, we revealed the significant difference in microbial community structure between low As groundwater samples (LG) and high As groundwater samples (HG). Acinetobacter, Thiovirga, Hydrogenophaga, and Sulfurimonas were dominant in LG, while Aquabcterium, Acinetobacter, Sphingomonas, Pseudomonas, Desulfomicrobium, Hydrogenophaga, and Nitrospira were predominant in HG. Shannon and Chao indices of the microbial communities in HG were significantly higher than those of in LG. Alpha diversity and abundance of arsC and arrA genes were higher than those of aioA genes. The significant positive correlation was uncovered between the abundances of arsC and aioA genes, suggesting the cooccurrence of As functional genes in groundwater. Sphingopyxis, Agrobacterium, Klebsiella, Hoeflea, and Aeromonas represented the dominant taxa within the As (V) reducers communities. Distance-based redundancy analysis showed that ORP, pH, As, Mn, and DOC were the key factors shaping the diverse microbial populations, while ORP, S, As(III), Fe(II), NH, pH, Mn, SO, As(V), temperature, and P as the main drivers affecting arsenotrophic microbiota. This work provides an insight into microbial communities linked to As biogeochemical processes in high As groundwater, playing a fundamental role in groundwater As cycling.
地下水中的高砷（As）是一个全球关注的环境问题，它与微生物介导的砷生物地球化学循环密切相关。然而，高砷地下水中与砷循环相关的基因分布以及潜在的微生物砷生物地球化学过程仍不清楚。因此，我们利用扩增子测序和qPCR技术，对中国典型高砷地区河套盆地地下水中的砷循环基因（arsC、arrA和aioA基因）和本地微生物群落进行了分析。在此，我们揭示了低砷地下水样本（LG）和高砷地下水样本（HG）之间微生物群落结构的显著差异。不动杆菌、硫弧菌、嗜氢菌和硫单胞菌在LG中占主导地位，而水生杆菌、不动杆菌、鞘氨醇单胞菌、假单胞菌、脱硫微菌、嗜氢菌和硝化螺菌在HG中占主导地位。HG中微生物群落的香农指数和 Chao 指数显著高于LG。arsC和arrA基因的α多样性和丰度高于aioA基因。arsC和aioA基因的丰度之间发现了显著的正相关，表明砷功能基因在地下水中共存。鞘氨醇杆菌属、土壤杆菌属、克雷伯氏菌属、霍夫勒菌属和气单胞菌属是砷（V）还原菌群落中的优势分类群。基于距离的冗余分析表明，氧化还原电位（ORP）、pH值、砷、锰和溶解性有机碳（DOC）是塑造不同微生物种群的关键因素，而ORP、硫、亚砷酸盐（As(III)）、亚铁（Fe(II)）、铵、pH值、锰、硫酸盐、砷酸盐（As(V)）、温度和磷是影响砷营养微生物群的主要驱动因素。这项工作深入了解了与高砷地下水中砷生物地球化学过程相关的微生物群落，在地下水砷循环中发挥着重要作用。
