title: Phosphorus availability from rock phosphate: Combined effect of green waste composting and sulfur addition.
abstract: Rock phosphate constitutes a natural phosphorus (P) source for organic farming systems, but with a limiting direct agricultural use due to its poor inherent reactivity. Thus, this work studies the effect of the co-composting of rock phosphate with green wastes and elemental sulfur on phosphorus availability. Six composts were prepared combining different green wastes and rock phosphate in three different proportions (0%, 0.27% and 0.54% P fresh mass basis) and elemental sulfur in two proportions (0% and 0.5% S fresh mass basis). During composting, the temperature of the mixtures was monitored, as were physico-chemical and chemical parameters, especially those related to phosphorus. The co-composting of green wastes with rock phosphate improved phosphorus mobilization and also constituted a viable method to manage green wastes, obtaining P-enriched compost for organic farming systems. Sulfur addition favored the composting process and also phosphorus solubilization, especially in the mixture with the lowest proportion of rock phosphate.
authors.affiliation: Department of Agrochemistry and Environment, Miguel Hernandez University, EPS-Orihuela, Ctra. Beniel Km 3.2, 03312, Orihuela, Alicante, Spain. Electronic address: marian.bustamante@umh.es.
authors.forename: M A
authors.initials: MA
authors.lastname: Bustamante
authors.affiliation: Department of Organic Agriculture, Mediterranean Agronomic Institute of Bari (CIHEAM-IAMB), Valenzano, Bari, Italy.
authors.forename: F G
authors.initials: FG
authors.lastname: Ceglie
authors.affiliation: Department of Organic Agriculture, Mediterranean Agronomic Institute of Bari (CIHEAM-IAMB), Valenzano, Bari, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Aly
authors.affiliation: Department of Organic Agriculture, Mediterranean Agronomic Institute of Bari (CIHEAM-IAMB), Valenzano, Bari, Italy.
authors.forename: H T
authors.initials: HT
authors.lastname: Mihreteab
authors.affiliation: Consiglio per la Ricerca e la sperimentazione in Agricoltura, Research Centre of soil-plant system (CRA-RPS), Rome, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Ciaccia
authors.affiliation: Consiglio per la Ricerca e la sperimentazione in Agricoltura, Research Centre of soil-plant system (CRA-RPS), Rome, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Tittarelli
mesh_terms: D000383:Agriculture / Q000379:methods*; D002244:Carbon / Q000737:chemistry; D004553:Electric Conductivity; D006863:Hydrogen-Ion Concentration; D009584:Nitrogen / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry; D010710:Phosphates / Q000032:analysis* / Q000737:chemistry; D010758:Phosphorus / Q000032:analysis* / Q000737:chemistry; D025341:Principal Component Analysis; D012987:Soil; D013455:Sulfur / Q000032:analysis* / Q000737:chemistry; D013696:Temperature
chemical_list: D009930:Organic Chemicals; D010710:Phosphates; D012987:Soil; D010758:Phosphorus; D013455:Sulfur; D002244:Carbon; D009584:Nitrogen
keywords: Compost; Elemental sulfur; Organic agriculture; Organic phosphorus; Phosphorus solubility