title: Nitrogen losses, uptake and abundance of ammonia oxidizers in soil under mineral and organo-mineral fertilization regimes.
abstract: BACKGROUND
  A laboratory incubation experiment and greenhouse studies investigated the impact of organo-mineral (OM) fertilization as an alternative practice to conventional mineral (M) fertilization on nitrogen (N) uptake and losses in perennial ryegrass (Lolium perenne) as well as on soil microbial biomass and ammonia oxidizers.
  
  
  RESULTS
  While no significant difference in plant productivity and ammonia emissions between treatments could be detected, an increase in soil total N content and an average 17.9% decrease in nitrates leached were observed in OM fertilization compared with M fertilization. The microbial community responded differentially to treatments, suggesting that the organic matter fraction of the OM fertilizer might have influenced N immobilization in the microbial biomass in the short-medium term. Furthermore, nitrate contents in fertilized soils were significantly related to bacterial but not archaeal amoA gene copies, whereas in non-fertilized soils a significant relationship between soil nitrates and archaeal but not bacterial amoA copies was found.
  
  
  CONCLUSIONS
  The application of OM fertilizer to soil maintained sufficient productivity and in turn increased N use efficiency and noticeably reduced N losses. Furthermore, in this experiment, ammonia-oxidizing bacteria drove nitrification when an N source was added to the soil, whereas ammonia-oxidizing archaea were responsible for ammonia oxidation in non-fertilized soil. © 2015 Society of Chemical Industry.
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di ricerca per lo studio delle relazioni tra pianta e suolo, Via della Navicella 2, 4-00184, Rome, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Florio
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di ricerca per lo studio delle relazioni tra pianta e suolo, Via della Navicella 2, 4-00184, Rome, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Felici
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di ricerca per lo studio delle relazioni tra pianta e suolo, Via della Navicella 2, 4-00184, Rome, Italy.
authors.forename: Melania
authors.initials: M
authors.lastname: Migliore
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di ricerca per lo studio delle relazioni tra pianta e suolo, Via della Navicella 2, 4-00184, Rome, Italy.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Dell'Abate
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di ricerca per lo studio delle relazioni tra pianta e suolo, Via della Navicella 2, 4-00184, Rome, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Benedetti
mesh_terms: D000641:Ammonia / Q000737:chemistry*; D001105:Archaea / Q000235:genetics / Q000378:metabolism; D001419:Bacteria / Q000235:genetics / Q000378:metabolism; D019641:DNA, Archaeal / Q000235:genetics; D004269:DNA, Bacterial; D005308:Fertilizers / Q000032:analysis*; D008129:Lolium; D009584:Nitrogen / Q000737:chemistry; D010084:Oxidation-Reduction; D012987:Soil / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D019641:DNA, Archaeal; D004269:DNA, Bacterial; D005308:Fertilizers; D012987:Soil; D014867:Water; D000641:Ammonia; D009584:Nitrogen
keywords: Lolium perenne; ammonia-oxidizing archaea; ammonia-oxidizing bacteria; nitrification; organo-mineral fertilization; soil microbial community