title: Composted organic wastes from the pharmaceutical and agro-food industries induce soil bioactivity and nodulation in alfalfa.
abstract: BACKGROUND
  Environmentally friendly agriculture needs to reduce the use of synthetic fertilizers and to reclaim nutrients from organic wastes. In this study the effect of five doses (0, 12, 24, 48 and 96 t ha(-1) ) of two two-phase olive mill waste (TPOMW)-based composts on the bioactivity and chemical characteristics of an agricultural soil and their potential to fertilize alfalfa (Medicago sativa) and stimulate nodulation were assessed during a two-year incubation experiment. The two composts were prepared either with the olive mill waste alone (compost A), which served as control, or mixed with a liquid fatty-proteinaceous hydrolyzate waste (FPH) from the pharmaceutical industry (compost AH).
  
  
  RESULTS
  Compost AH resulted in greater N immobilization than compost A because the former supplied the soil with easily degradable C and N, which increased microbial biomass and activity. Both compost mineralizations during the first year of incubation supplied the soil with more nutrients (mainly N), more so with A than with AH. Nevertheless, plant growth was similar in soils amended with either A or AH. Both composts induced nodulation similarly and the highest dose (96 t ha(-1) ) increased the formation of nodules by a factor of 11 compared with the four lower doses.
  
  
  CONCLUSIONS
  TPOMW serves as an effective ground material for co-composting with liquid wastes such as FPH. TPOMW supplies key nutrients and stimulates nodulation in alfalfa.
authors.affiliation: Grupo RESIAGRI, Instituto Agroforestal Mediterráneo, Universitat Politècnica de València, Camino de Vera s/n, E-46020, Valencia, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Fornes
authors.forename: Claudia X
authors.initials: CX
authors.lastname: Jaramillo
authors.forename: Rosana
authors.initials: R
authors.lastname: García-de-la-Fuente
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Belda
authors.forename: Antonio
authors.initials: A
authors.lastname: Lidón
mesh_terms: D000383:Agriculture; D001419:Bacteria / Q000187:drug effects / Q000378:metabolism; D018533:Biomass; D004345:Drug Industry; D019649:Food Industry; D007220:Industrial Waste / Q000032:analysis*; D000455:Medicago sativa / Q000382:microbiology* / Q000502:physiology*; D009584:Nitrogen / Q000737:chemistry / Q000378:metabolism; D055170:Plant Root Nodulation / Q000187:drug effects*; D012037:Refuse Disposal / Q000379:methods*; D053204:Root Nodules, Plant; D012987:Soil; D012988:Soil Microbiology
chemical_list: D007220:Industrial Waste; D012987:Soil; D009584:Nitrogen
keywords: Medicago sativa; microbial biomass; nitrogen dynamics; nodulation index; soil respiration; ‘alperujo’