title: Modelling nitrogen and carbon interactions in composting of animal manure in naturally aerated piles.
abstract: Composting animal manure with natural aeration is a low-cost and low-energy process that can improve nitrogen recycling in millions of farms world-wide. Modelling can decrease the cost of choosing the best options for solid manure management in order to decrease the risk of loss of fertilizer value and ammonia emission. Semi-empirical models are suitable, considering the scarce data available in farm situations. Eleven static piles of pig or poultry manure were monitored to identify the main processes governing nitrogen transformations and losses. A new model was implemented to represent these processes in a pile considered as homogeneous. The model is based on four modules: biodegradation, nitrogen transformations and volatilization, thermal exchanges, and free air space evolution. When necessary, the parameters were calibrated with the data set. The results showed that microbial growth could reduce ammonia volatilization. Greatest nitrogen conservation is achieved when microbial growth was limited by nitrogen availability.
authors.affiliation: CIRAD, UR Recyclage et risque, Avenue Agropolis, F-34398 Montpellier Cedex 5, France; Crête d'Or Entreprise, F-97427 Etang Salé, France.
authors.forename: D
authors.initials: D
authors.lastname: Oudart
authors.affiliation: INRA, UMR1069 Sol Agro et hydrosystèmes Spatialisation, F-35000 Rennes, France; Agrocampus Ouest, F-35000 Rennes, France. Electronic address: paul.robin@rennes.inra.fr.
authors.forename: P
authors.initials: P
authors.lastname: Robin
authors.affiliation: CIRAD, UR Recyclage et risque, Avenue Agropolis, F-34398 Montpellier Cedex 5, France.
authors.forename: J M
authors.initials: JM
authors.lastname: Paillat
authors.affiliation: Université de Toulouse, INSA, UPS, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse Cedex 4, France; INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France; CNRS, UMR5504, F-31400 Toulouse, France.
authors.forename: E
authors.initials: E
authors.lastname: Paul
mesh_terms: D000641:Ammonia / Q000378:metabolism*; D000818:Animals; D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002244:Carbon / Q000378:metabolism*; D006358:Hot Temperature; D008372:Manure / Q000032:analysis*; D008962:Models, Theoretical; D009584:Nitrogen / Q000378:metabolism*; D011200:Poultry; D034421:Sus scrofa; D014835:Volatilization; D018505:Waste Management
chemical_list: D008372:Manure; D002244:Carbon; D000641:Ammonia; D009584:Nitrogen
keywords: Ammonia; Composting; Livestock; Manure; Nitrogen; Nitrous oxide