Supply of agricultural biomass residues for on-farm composting: a cross-analysis of relevant data sets for the most sustainable management combination

Agricultural crop production can generate significant residues and their management is generally a disposal problem. Composting can be a solution. It is essentially an efficient bioconversion technique to process organic wastes (manure, food, crop and forestry residues, solid digestate) into humus-like substances destined to different uses (soil amendment, organic fertilization, plant nursery substrates). Life Cycle Assessment, Energy Analysis, and Life Cost Costing were used to perform a cross-analysis aimed to assess the environmental, economic, and energy sustainability of some procurement systems of compostable materials (bulking agents and agricultural crop residues) to be allocated to composting on the farm. The procurement systems were characterized by different mechanization levels in order to explore the possible scenarios related to the availability of vehicles within the farm and increasing transport distances. Our findings underline that the most sustainable option for the environment it was not often the most cost-effective choice. Therefore, the cross-analysis of these relevant data sets allowed us to detail the different operative steps and guide the procurement system choice toward those showing the best compromise for both the environment and farmers (cheaper, with no or low impactful).