Bacterial Communities in the Groundwater of Xikuangshan Antimony Mine, China

Xikuangshan (XKS) is the biggest antimony (Sb) mine around the word, which causes serious environmental contamination due to the mining actives. To fully understand the bacterial compositions in the groundwater around the mining area in XKS and their correlation with environmental factors, groundwater samples were collected and subject to 16S rDNA high throughput sequencing. Results indicated that Proteobacteria (especially Gamma-Proteobacteria) dominated bacterial communities in high-Sb groundwater samples, whereas Bacteroidetes predominated in low-Sb groundwater. Furthermore, antimony concentration was found to be the most significant factor shaping bacterial communities (P=0.002) with an explanation of 9.16% of the variation. Other factors such as pH, contents of Mg, Ca and orthophosphate were also observed to significantly correlate with bacterial communities. This was the first report to show the important impact of Sb concentration on bacterial community structure in the groundwater in the mining area. Our results will enhance the understanding of subsurface biogeochemical processes mediated by microbes.