title: Effects of digestate on soil chemical and microbiological properties: A comparative study with compost and vermicompost.
abstract: Anaerobic digestion has become increasingly popular as an alternative for recycling wastes from different origins. Consequently, biogas residues, most of them with unknown chemical and biological composition, accrue in large quantities and their application into soil has become a widespread agricultural practise. The aim of this study was to evaluate the effects of digestate application on the chemical and microbiological properties of an arable soil in comparison with untreated manure, compost and vermicompost. Once in the soil matrix either the addition of compost or digestate led to an increased nitrification rate, relative to unamended and manure-treated soil, after 15 and 60 days of incubation. Faecal coliform and E. coli colony forming units (CFUs) were not detected in any of the amended soils after 60 days. The highest number of Clostridium perfringens CFUs was recorded in manure-amended soil at the beginning of the experiment and after 15 days; whilst after 60 days the lowest CFU number was registered in digestate-treated soil. Denaturing gradient gel electrophoresis patterns also showed that besides the treatment the date of sampling could have contributed to modifications in the soil ammonia-oxidising bacteria community, thereby indicating that the soil itself may influence the community diversity more strongly than the treatments.
authors.affiliation: University of Innsbruck, Institute of Microbiology, Technikerstrasse 25d, 6020 Innsbruck, Austria. Electronic address: Maria.Gomez-Brandon@uibk.ac.at.
authors.forename: María
authors.initials: M
authors.lastname: Gómez-Brandón
authors.affiliation: University of Innsbruck, Institute of Microbiology, Technikerstrasse 25d, 6020 Innsbruck, Austria.
authors.forename: Marina Fernández-Delgado
authors.initials: MF
authors.lastname: Juárez
authors.affiliation: University of Innsbruck, Institute of Microbiology, Technikerstrasse 25d, 6020 Innsbruck, Austria.
authors.forename: Matthias
authors.initials: M
authors.lastname: Zangerle
authors.affiliation: University of Innsbruck, Institute of Microbiology, Technikerstrasse 25d, 6020 Innsbruck, Austria.
authors.forename: Heribert
authors.initials: H
authors.lastname: Insam
mesh_terms: D000818:Animals; D018533:Biomass; D003016:Clostridium perfringens / Q000302:isolation & purification; D004926:Escherichia coli / Q000302:isolation & purification; D008372:Manure; D064307:Microbiota; D058465:Nitrification; D009835:Oligochaeta; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology
chemical_list: D008372:Manure; D012987:Soil
keywords: Ammonia-oxidising bacteria; Anaerobic digestion; Nitrification rate; Organic amendment; Pathogenic bacteria