Composting: The way for a sustainable agriculture

Compost, as stabilized organic matter, can be virtuously used for the recovery of degraded soils and their fertility restoring, carbon sequestration in the soil and the reduction in the use of chemical inputs (fertilizers, pesticides, fuel) resulting in the decrease of production costs and negative environmental impacts. Additionally, compost can be successfully used in other productive (nursery) and landscape-environmental-hobby activities (green areas, recovery of waste dumps, gardening, etc.). Choosing the most appropriate composting technology depends on some farm evaluations (volumes of materials to be composted, matrixes type and their supply places, machinery/facilities already present in the farm) and preliminary analyses of environmental and economic sustainability to be performed by means of methodologies such as Life Cycle Assessment, Life Cycle Costing and Energy Analysis. This article briefly describes the on-farm composting technologies, available today, and reports the results of the environmental, energy and economic sustainability analysis of 5 composting plants using different composting technologies and starting matrices (bulking agents and compostable materials). These plants were built within some National and European researches and transfer projects in Basilicata and Campania regions. Generally, on-farm composting resulted as a strategic technology for the sustainability of agricultural activities that can thus solve critical issues such as the disposal of crop residues and livestock wastes. From our results, obtained under different logistic and farming conditions, on-farm composting seems to be the most sustainable solution - from economic and environmental point of views - if compared to the ordinary agricultural waste disposal methods. In perspective, it is recommended the creation of wide farm networks for the optimization of all steps of the composting chain.