The adaptative capacity of a viticultural area (Valle Telesina, Southern Italy) to climate changes

The viticulture aiming at the production of high quality wine is very important for the landscape conservation, because it allows to combine high farmer income with soil conservation. The quality of grape and wine is variety-specific and it depends significantly on the pedoclimatic conditions. The evolution of climate may thus endanger not only yield (IPCC, 2007) but, more significantly, the sustainability of current varieties. Adaptation of current production systems may be feasible, but requires a timely evaluation of whether adaptation to climate evolution might be limited to improving crop and soil management or should involve replacement of cvs or species altogether.
This study addressed this question by evaluating the adaptive capacity of a 20000 ha viticultural area in the “Valle Telesina” (Campania Region, Southern Italy). This area has a long tradition in the production of high quality wines (DOC and DOCG) and it is characterized by a complex geomorphology with a large soil and climate variability.
Two climate periods were considered: “past” (1984-1996) and “present” (2000-2009), which show a pattern of climate variability. The periods were taken as an example of different scenarios generated by climate changes.
The Amerine & Winkler index was calculated in each climate period and compared with the thermal requirements of a set of grapevine cvs, including the ones currently cultivated in the area.
Due to the observed trend of temperature increase from the “past” to the “present” period, differences were detected in the A&W index’s values and spatial distribution. When compared with the A&W indexes of the grape varieties the temperature increase resulted in a considerable increase of the area eligible to some varieties (Guarnaccia and Forastera) and a strong reduction of the area suitable for some of the most important current varieties (Aglianico and Falanghina).
Moreover, the hydrological model SWAP was applied to estimate the Crop Water Stress Index (CWSI) in the “present” climatic period, in order to evaluate the effects of the re-distribution of the cultivars over the study area on vineyards’ water balance.
This approach is being applied to other crops and other production systems towards quantitative, realistic studies on the adaptation of agriculture to climate evolution.