title: Benefits for agriculture and the environment from urban waste.
abstract: Soluble bio-based substances (SBO) that have been isolated from urban biowaste have recently been reported to enhance plant leaf chlorophyll content and growth. The same SBO have also been shown to enhance the photochemical degradation of organic pollutants in industrial effluent. These findings suggest that SBO may promote either C fixation or mineralization, according to operating conditions. The present work aims to investigate SBO performance, as a function of source material. Thus, three materials have been sampled from a municipal waste treatment plant: (i) the digestate of the anaerobic fermentation of a humid organic fraction, (ii) a whole vegetable compost made from gardening residues and (iii) compost made from a mixture of digestate, gardening residues and sewage sludge. These materials were hydrolyzed at pH13 and 60°C to yield SBO that display different chemical compositions. These products were applied to soil at 30, 145 and 500 kg ha(-1) doses for tomato cultivation. Soil and plant leaf chemical composition, plant growth, leaf chlorophyll content and CO2 exchange rate as well as fruit quality and production rate were measured. Although it did not affect the soil's chemical composition, SBO were found to significantly increase plant photosynthetic activity, growth and productivity up to the maximum value achieved at 145 kg ha(-1). The effects were analyzed as a function of SBO chemical composition and applied dose. The results of this work, compared with those of previous works, indicate that urban biowaste, if properly exploited, may furnish conjugate economic and environmental benefits, within a friendly sustainable ecosystem.
authors.affiliation: Dipartimento di Scienze Agronomiche Agrochimiche e delle Produzioni Animali, Università degli Studi di Catania, Via Valdisavoia 5, Catania 95123, Italy.
authors.forename: Orazio
authors.initials: O
authors.lastname: Sortino
authors.affiliation: STAR Integrated Research, University of Foggia, Via Gramsci 89-91, Foggia 71121, Italy. Electronic address: enzo.montoneri@gmail.com.
authors.forename: Enzo
authors.initials: E
authors.lastname: Montoneri
authors.affiliation: Consiglio Nazionale delle Ricerche (CNR), Istituto per i Sistemi Agricoli e Forestali del Mediterraneo (ISAFoM), Catania, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Patanè
authors.affiliation: Dipartimento di Chimica, Università di Torino, Via P. Giuria 7, Torino 10125, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Rosato
authors.affiliation: Dipartimento di Chimica, Università di Torino, Via P. Giuria 7, Torino 10125, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Tabasso
authors.affiliation: Dipartimento di Chimica, Università di Torino, Via P. Giuria 7, Torino 10125, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Ginepro
mesh_terms: D000383:Agriculture / Q000379:methods*; D003247:Conservation of Natural Resources; D012037:Refuse Disposal / Q000379:methods*; D012987:Soil / Q000737:chemistry
chemical_list: D012987:Soil
keywords: CO(2) exchange rate; Chlorophyll; Municipal biowastes; Photo sensitizers; Plant growth and productivity; Plant photosynthetic activity