TY - JOUR A1 - Pilloni, Giovanni A1 - Bayer, Anne A1 - Ruth-Anneser, Bettina A1 - Fillinger, Lucas A1 - Engel, Marion A1 - Griebler, Christian A1 - Lueders, Tillmann T1 - Dynamics of Hydrology and Anaerobic Hydrocarbon Degrader Communities in A Tar-Oil Contaminated Aquifer JF - Microorganisms N2 - Aquifers are typically perceived as rather stable habitats, characterized by low biogeochemical and microbial community dynamics. Upon contamination, aquifers shift to a perturbed ecological status, in which specialized populations of contaminant degraders establish and mediate aquifer restoration. However, the ecological controls of such degrader populations, and possible feedbacks between hydraulic and microbial habitat components, remain poorly understood. Here, we provide evidence of such couplings, via 4 years of annual sampling of groundwater and sediments across a high-resolution depth-transect of a hydrocarbon plume. Specialized anaerobic degrader populations are known to be established at the reactive fringes of the plume. Here, we show that fluctuations of the groundwater table were paralleled by pronounced dynamics of biogeochemical processes, pollutant degradation, and plume microbiota. Importantly, a switching in maximal relative abundance between dominant degrader populations within the Desulfobulbaceae and Desulfosporosinus spp. was observed after hydraulic dynamics. Thus, functional redundancy amongst anaerobic hydrocarbon degraders could have been relevant in sustaining biodegradation processes after hydraulic fluctuations. These findings contribute to an improved ecological perspective of contaminant plumes as a dynamic microbial habitat, with implications for both monitoring and remediation strategies in situ. KW - BTEX KW - anaerobic toluene degradation KW - benzylsuccinate synthase KW - microbial community dynamics KW - next-generation sequencing Y1 - 2020 UR - https://doi.org/10.3390/microorganisms7020046 VL - 7 IS - 2 SP - 46 ER -