Stochastic assembly process dominates bacterial succession during a long-term microbial enhanced oil recovery

TY - JOUR

T1 - Stochastic assembly process dominates bacterial succession during a long-term microbial enhanced oil recovery

AU - Yun, Yuan

AU - Gui, Ziyu

AU - Xie, Jinxia

AU - Chen, Yu

AU - Tian, Xuefeng

AU - Li, Guoqiang

AU - Gu, Ji Dong

AU - Ma, Ting

N1 - Publisher Copyright: © 2021 The Authors

PY - 2021/10/10

Y1 - 2021/10/10

N2 - Microbial enhanced oil recovery (MEOR) has been successfully used in oil exploitation to increase oil production. However, the mechanisms of microbial interactions and community assembly related to oil production performance along MEOR process are poorly understood. Here, we investigated the microbiome of an oil reservoir for a period of 5 years under three phases of different treatments with the injection of a mixture of microbes, nutrients, and air at different intensity. During the MEOR process, amplification of functional genes revealed an increase of genes related to hydrocarbon degradation linked to methanogenesis, supported by stable isotope analysis for confirmation of the methanogenesis activity. Meanwhile, a lower contribution of the ubiquitous/common taxa, closer and more positive associations, and lower modularity were observed in bacterial co-occurrence networks, with the rare taxa being the keystone taxa. The null model analysis and structural equation modeling revealed that the contribution of stochastic processes affected by functional groups and co-occurrence patterns to bacterial community increased significantly with the increase of oil production. This provides new insight that stochastic assembly in bacterial community increased along with MEOR process, and it is worthwhile paying attention to the uncertain consequences caused by random evolution since the treatment effect of MEOR is closely related to the in-situ community in oil reservoir.

AB - Microbial enhanced oil recovery (MEOR) has been successfully used in oil exploitation to increase oil production. However, the mechanisms of microbial interactions and community assembly related to oil production performance along MEOR process are poorly understood. Here, we investigated the microbiome of an oil reservoir for a period of 5 years under three phases of different treatments with the injection of a mixture of microbes, nutrients, and air at different intensity. During the MEOR process, amplification of functional genes revealed an increase of genes related to hydrocarbon degradation linked to methanogenesis, supported by stable isotope analysis for confirmation of the methanogenesis activity. Meanwhile, a lower contribution of the ubiquitous/common taxa, closer and more positive associations, and lower modularity were observed in bacterial co-occurrence networks, with the rare taxa being the keystone taxa. The null model analysis and structural equation modeling revealed that the contribution of stochastic processes affected by functional groups and co-occurrence patterns to bacterial community increased significantly with the increase of oil production. This provides new insight that stochastic assembly in bacterial community increased along with MEOR process, and it is worthwhile paying attention to the uncertain consequences caused by random evolution since the treatment effect of MEOR is closely related to the in-situ community in oil reservoir.

KW - Co-occurrence network

KW - Community assembly

KW - Hydrocarbon degrading bacteria

KW - Microbial enhanced oil recovery

KW - Oil reservoir

UR - http://www.scopus.com/inward/record.url?scp=85107595158&partnerID=8YFLogxK

U2 - 10.1016/j.scitotenv.2021.148203

DO - 10.1016/j.scitotenv.2021.148203

M3 - 文章

C2 - 34380257

AN - SCOPUS:85107595158

SN - 0048-9697

VL - 790

JO - Science of the Total Environment

JF - Science of the Total Environment

M1 - 148203

ER -