A new dynamic viticultural zoning approach to explore the resilience of terroir concept under climate change: the case study of Aglianico grapevine in southern Italy

Climate change directly influences agricultural sectors, presenting the need to identify mitigating actions that can make local farming communities and crop production more resilient. In this context, the viticultural sector is one of those most challenged by climate change (CC) due to its great impact on grapevine cultivar adaptation, also generating a high degree of uncertainty about expected grape quality and, therefore, farmers' future incomes. Therefore, understanding how suitability for viticulture is changing under CC is of primary interest in the development of adaptation strategies in traditional wine-growing regions. Within this framework, the planning and managing of vineyards that aim at high quality wine is carried out by means of viticultural zoning procedures which are mostly based on empirical approaches. Considering that climate is an essential part of the terroir system, the expected variability in climate change could have a marked influence on terroir resilience with important effects on local farming communities in viticultural regions. From this perspective, the aim of this paper is to define a new dynamic viticultural zoning procedure (DVZ) that is able to integrate the effects of CC on grape quality responses and evaluate terroir resilience, providing a support tool for stakeholders involved in viticultural planning (winegrowers, winegrower consortiums, policy makers etc.). To achieve these aims, a Hybrid Land Evaluation System (HLES), combining qualitative (standard Land Evaluation system) and quantitative (simulation model) approaches, was applied within a traditional region devoted to high quality wine production in Southern Italy (Valle Telesina, BN), for a specific grapevine cultivar (Aglianico), considering high resolution climate projections that were derived under two different IPCC scenarios, namely RCP 4.5 and RCP8.5. The results obtained indicate that: (i) only 2% of the suitable area of Valle Telesina expresses the concept of terroir resilience oriented towards Aglianico ultra quality grape (UQG) production; (ii) within 2010-2040, it is expected that 41% of the area suitable for Aglianico cultivation will need irrigation to achieve quality grape production; (iii) by 2100, climate change benefits for the cultivation of Aglianico will decrease, as well as the suitable area.