Improved Compost Production from Fruit and Vegetable Market Waste: A Case Study in Bagua, Amazonas (Peru)

Abstract

Inadequate management of organic solid waste in municipal markets represents a critical environmental challenge in tropical developing regions, where high humidity (>80%) and elevated temperatures (>25°C) accelerate decomposition, generating leachate and greenhouse gas emissions. In Peru, over 50% of municipal waste is organic, yet less than 20% is valorised through composting, highlighting a substantial technological gap. This study evaluated an improved composting system (the Bagua Method) applied to fruit and vegetable waste from the Municipal Market of Bagua, Peruvian Amazon, over seven years (2018–2024). A comparative experimental design with triplicate piles (n = 6) compared enzyme-amended piles (Bagua Method) against non-enzyme controls. Comprehensive physicochemical characterisation followed standard methods (AOAC, Walkley-Black, Kjeldahl), including moisture, ash, total organic carbon, nitrogen, pH, electrical conductivity, bulk density, and germination index. Statistical analysis employed two-way ANOVA with Tukey HSD post-hoc testing. A structured survey assessed waste management practices among 30 market traders. The Bagua Method achieved 88.8–89.5% recovery efficiency, converting 21.9±0.9 t year⁻¹ of organic residues into 8.3–9.2 t year⁻¹ of quality compost. Enzymatic amendment reduced composting time to 60 days (33% faster than controls), with thermophilic temperatures (>55°C) reached within 48±6 hours. Final compost met Ö-NORM S 2022 standards: C/N ratio 18.9±0.7, pH 8.5±0.2, EC 3.1±0.3 mS/cm, and germination index 95±3% versus 78±4% for controls (p<0.001). Survey results indicated that 11% trader participation contributed 40% of usable waste; scaling to 30% participation could achieve 94% recovery efficiency. The Bagua Method constitutes a technically viable, environmentally sustainable, and socially inclusive alternative for organic waste recovery, contributing to circular economy principles and SDGs 11, 12, and 15. The method demonstrates substantial scaling potential across Peru's northern macro-region, with capacity to divert ~50,000 t year⁻¹ of waste and create 200+ green jobs.