title: Dynamic Succession of Groundwater Functional Microbial Communities in Response to Emulsified Vegetable Oil Amendment during Sustained In Situ U(VI) Reduction.
abstract: A pilot-scale field experiment demonstrated that a one-time amendment of emulsified vegetable oil (EVO) reduced groundwater U(VI) concentrations for 1 year in a fast-flowing aquifer. However, little is known about how EVO amendment stimulates the functional gene composition, structure, and dynamics of groundwater microbial communities toward prolonged U(VI) reduction. In this study, we hypothesized that EVO amendment would shift the functional gene composition and structure of groundwater microbial communities and stimulate key functional genes/groups involved in EVO biodegradation and reduction of electron acceptors in the aquifer. To test these hypotheses, groundwater microbial communities after EVO amendment were analyzed using a comprehensive functional gene microarray. Our results showed that EVO amendment stimulated sequential shifts in the functional composition and structure of groundwater microbial communities. Particularly, the relative abundance of key functional genes/groups involved in EVO biodegradation and the reduction of NO3 (-), Mn(IV), Fe(III), U(VI), and SO4 (2-) significantly increased, especially during the active U(VI) reduction period. The relative abundance for some of these key functional genes/groups remained elevated over 9 months. Montel tests suggested that the dynamics in the abundance, composition, and structure of these key functional genes/groups were significantly correlated with groundwater concentrations of acetate, NO3 (-), Mn(II), Fe(II), U(VI), and SO4 (2-). Our results suggest that EVO amendment stimulated dynamic succession of key functional microbial communities. This study improves our understanding of the composition, structure, and function changes needed for groundwater microbial communities to sustain a long-term U(VI) reduction.
authors: Institute for Environmental Genomics and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
authors: Ping
authors: P
authors: Zhang
authors: Department of Civil and Environmental Engineering, Stanford University, Stanford, California, USA.
authors: Wei-Min
authors: WM
authors: Wu
authors: Institute for Environmental Genomics and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
authors: Joy D
authors: JD
authors: Van Nostrand
authors: Institute for Environmental Genomics and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
authors: Ye
authors: Y
authors: Deng
authors: Institute for Environmental Genomics and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
authors: Zhili
authors: Z
authors: He
authors: Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
authors: Thomas
authors: T
authors: Gihring
authors: Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
authors: Gengxin
authors: G
authors: Zhang
authors: Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
authors: Chris W
authors: CW
authors: Schadt
authors: Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
authors: David
authors: D
authors: Watson
authors: Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
authors: Phil
authors: P
authors: Jardine
authors: Department of Civil and Environmental Engineering, Stanford University, Stanford, California, USA.
authors: Craig S
authors: CS
authors: Criddle
authors: Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
authors: Scott
authors: S
authors: Brooks
authors: Center for Microbial Ecology, Michigan State University, East Lansing, Michigan, USA.
authors: Terence L
authors: TL
authors: Marsh
authors: Center for Microbial Ecology, Michigan State University, East Lansing, Michigan, USA.
authors: James M
authors: JM
authors: Tiedje
authors: Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA.
authors: Adam P
authors: AP
authors: Arkin
authors: Institute for Environmental Genomics and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China jzhou@ou.edu.
authors: Jizhong
authors: J
authors: Zhou
mesh_terms: D000085:Acetates / Q000378:metabolism; D001673:Biodegradation, Environmental; D004655:Emulsions / Q000737:chemistry; D060587:Groundwater / Q000382:microbiology*; D046228:Microarray Analysis; D059013:Microbial Consortia / Q000235:genetics* / Q000502:physiology*; D010938:Plant Oils; D013431:Sulfates / Q000378:metabolism; D013997:Time Factors; D014501:Uranium / Q000378:metabolism*; D014875:Water Pollutants, Radioactive / Q000378:metabolism*
chemical_list: D000085:Acetates; D004655:Emulsions; D010938:Plant Oils; D013431:Sulfates; D014875:Water Pollutants, Radioactive; D014501:Uranium