Windrow composting as horticultural waste management strategy – A case study in Ecuador

• Published in: Waste management (Elmsford) Vol. 48; pp. 127 - 134
• Main Authors: Gavilanes-Terán, Irene, Jara-Samaniego, Janneth, Idrovo-Novillo, Julio, Bustamante, Ma Angeles, Moral, Raúl, Paredes, Concepción
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.02.2016
• Subjects: Agriculture; Animals; Biodegradation, Environmental; Brassica; Broccoli waste; Carbon; Chickens; Compost maturity; Composting; Ecuador; Evolution; Female; Fertilizers; Germination; Lycopersicon esculentum; Manure; Metals, Heavy - analysis; New technology; Organic matter degradation; Piles; Plant nutrient; Principal Component Analysis; Soil; Temperature; Tomato waste; Vegetables; Waste management; Waste Management - methods; Waste Products; Wastes; ISE, Ecuador; Organic matter degradation; Composting; Broccoli waste; Tomato waste; Compost maturity; Plant nutrient
• ISSN: 0956-053X; 1879-2456
• DOI: 10.1016/j.wasman.2015.11.026

•Composting of horticultural waste with hen manure and sawdust is a promising alternative to landfills.•The horticultural waste composts had a good degree of stability and maturity.•The use of tomate waste increased the fertilising capacity of the compost obtained.•The environmental problems associated with the composting process were greater in the mixture with broccoli waste. In Ecuador, enormous quantities of vegetable wastes are produced annually from the horticultural industries. Composting can be a feasible treatment to stabilise horticultural wastes and, thus, to improve their properties for use as organic fertilisers. In this study, two different piles were prepared, using laying hen manure and sawdust mixed with broccoli or tomato waste, respectively, and composted by the turned windrow composting system. Throughout the composting process, the temperature of the mixtures was monitored and physico-chemical and chemical properties and the degree of maturity were determined. Also, principal component analysis was used to interpret the data set of compost characteristics. In both piles, the temperature exceeded 55°C for more than 2weeks, which ensured maximum pathogen reduction. Organic matter (OM) losses followed a first-order kinetic equation in both piles. The final composts showed a suitable degree of stability and maturity and an absence of phytotoxins, as observed in the evolution and final values of the total organic carbon/total nitrogen ratio (Corg/NT<20), water-soluble organic carbon (Cw<1.7%), germination index (GI>50%) and cation exchange capacity (CEC>67meq (100g OM)−1). As well, the evolution of different humification indexes during composting was a good indicator of the OM humification process. The type of vegetable waste used influenced OM and NT mineralisation and the final properties of the composts, showing the mixture with tomato waste a higher fertilising capacity and less environmental problems.