Hazelnut Cultivation in the Campania Region: Environmental Sustainability of the Recovery of Pruning Residues and Shells through the Life Cycle Assessment Methodology

Promoting sustainable agriculture is one of the challenges of our century. Thus, this research aimed to estimate the environmental sustainability of hazelnut cultivation in the Campania region (Southern Italy), both in quantitative and economic terms, by estimating the social cost of the pollution. The evaluation of the recovery of pruning residues and shells, from a circular economy perspective, represents the novelty of this paper. The lifecycle assessment methodology was used to analyze and compare twenty-one hazelnut systems that are very different from each other. The results showed that the impacts per kg of unshelled hazelnuts varied among the systems, depending on the impact category considered, and with respect to climate change, the lowest value was 0.32 kg CO2 eq (in BIO4 system), while the highest was 2.48 kg CO2 eq (in INT8 system). Moreover, organic management was more environmentally friendly for almost all impact categories, and ordinary cultivation techniques were the most impactful. Cultivation on embankments or terraced soils had a greater impact when compared to flat soils, especially due to the greater fuel consumption during farm–field transport. Emergency irrigation did not cause an increase in impact if the overall management was sustainable. In economic terms, the total cost of pollution of the agricultural phase varied from a minimum of EUR 0.11 per kg of hazelnuts to a maximum of EUR 0.70. Post-harvest operations up to vacuum packaging did not make any systems more impactful than others since their agricultural management was more sustainable than many others. In accordance with the objectives of the European Green Deal, the recovery of pruning material and shells on farms has proven to be very important for reducing impacts, especially if they are used to replace methane and diesel oil, hence the importance of pursuing this research to make hazelnut cultivation ever more sustainable.