Climatic zoning and viticulture in Galicia (North West Spain)

La délimitation et la caractérisation des zones viticoles posent en Espagne des problèmes spécifiques non seulement dus aux caractéristiques propres au territoire mais aussi à la dimension, la distribution et l’indice d’occupation viticole dans les appellations d’origine.

Canopy-management practices are applied in viticulture to improve berries composition and quality, having a great impact on primary and secondary grape metabolism. Among these techniques, cluster zone leaf removal (defoliation) is widely used to manage air circulation, temperature and light radiation of grape bunches and close environment. Since volatiles are quantitatively and qualitatively influenced by the degree of fruit ripeness, the level of solar exposure, and the thermal environment in which grapes ripen, leaf removal has been shown to affect volatile composition of grape berries [1].

The impact of climate change is noticeable in the present weather, making water scarcity the most immediate mediator reducing the performance and viability of crops, including grapevine (Vitis vinifera L.). The present study developed a system (hardware, firmware, and software) for the determination of plant water use through changes in weight through a period. The aim is to measure the differences in grapevine water consumption in response to climate change (+4oC and 700 ppm) under controlled conditions. The results reveal a correlation between daily plant consumption rates and reference evapotranspiration (ETo).

In recent years, the increase in temperature and the changes in rainfall distribution caused by climate change are affecting vine and grape physiology and are consequently impacting wine composition and quality (Schultz, 2000; Jones et al., 2005).

Sforzato di Valtellina DOCG is a special reinforced red wine produced using withered Nebbiolo grapes. The withering process takes place in traditional rooms under natural environmental conditions; it starts immediately after the harvest and ends not before the 1st December of the same year. The process can be performed with different bunch placements that can influence the grapes features.The purpose of the study is to compare the effect on grape physico-chemical parameters for four withering bunch placement systems: hanged clusters (HC), plastic crates (CT), breathable mesh fabric on wooden frames panels (MF), and reed mats (RM). For all the systems studied, the withering length was two months at a temperature between 6 and 19 °C and a relative humidity of 41-88%.