title: Seasonal Patterns in Microbial Community Composition in Denitrifying Bioreactors Treating Subsurface Agricultural Drainage.
abstract: Denitrifying bioreactors, consisting of water flow control structures and a woodchip-filled trench, are a promising approach for removing nitrate from agricultural subsurface or tile drainage systems. To better understand the seasonal dynamics and the ecological drivers of the microbial communities responsible for denitrification in these bioreactors, we employed microbial community "fingerprinting" techniques in a time-series examination of three denitrifying bioreactors over 2 years, looking at bacteria, fungi, and the denitrifier functional group responsible for the final step of complete denitrification. Our analysis revealed that microbial community composition responds to depth and seasonal variation in moisture content and inundation of the bioreactor media, as well as temperature. Using a geostatistical analysis approach, we observed recurring temporal patterns in bacterial and denitrifying bacterial community composition in these bioreactors, consistent with annual cycling. The fungal communities were more stable, having longer temporal autocorrelations, and did not show significant annual cycling. These results suggest a recurring seasonal cycle in the denitrifying bioreactor microbial community, likely due to seasonal variation in moisture content.
authors.affiliation: Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.|Environmental Resources Management, 1701 Golf Road, Suite 1-700, Rolling Meadows, IL, 60008, USA.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Porter
authors.affiliation: Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.|Waterborne Environmental, Inc., 2001 S First Street, Suite 109, Champaign, IL, 61820, USA.
authors.forename: J Malia
authors.initials: JM
authors.lastname: Andrus
authors.affiliation: Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.|Strand Associates, Inc., 910 West Wingra Drive, Madison, WI, 53715, USA.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Bartolerio
authors.affiliation: Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
authors.forename: Luis F
authors.initials: LF
authors.lastname: Rodriguez
authors.affiliation: Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
authors.forename: Yuanhui
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
authors.forename: Julie L
authors.initials: JL
authors.lastname: Zilles
authors.affiliation: Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA. akent@illinois.edu.
authors.forename: Angela D
authors.initials: AD
authors.lastname: Kent
mesh_terms: D000383:Agriculture; D018407:Bacterial Physiological Phenomena; D019149:Bioreactors / Q000382:microbiology*; D058440:Denitrification; D005658:Fungi / Q000502:physiology*; D007087:Illinois; D064307:Microbiota; D012621:Seasons; D014874:Water Pollutants, Chemical / Q000378:metabolism
chemical_list: D014874:Water Pollutants, Chemical
keywords: Denitrification; Geostatistics; Nitrate removal; Seasonal variation; Subsurface drainage