Anthropogenic intervention in shaping Terroir in a California Pinot noir vineyard

Grapevine grafting is a complex process that since the establishment of phylloxera has become mandatory for grapevine. Grafting success in grapevine nurseries considerably varies among years and batches with most variety/rootstock combinations reach a high success rate (between 75% and 90%), but some combinations show lower success rates of around 40-50%. The causes of this variation are unknown, although biotic stresses like those caused by some viral infections have been demonstrated to affect the process. European certification schemes for the vegetative propagation of the vine include five major viruses (Arabis mosaic virus, Grapevine Fanleaf Virus, Grapevine Fleck Virus, and Grapevine-associated Leafroll Virus 1 and 3).

The vineyard of Bergerac, a guaranteed vintage, is situated in the mid-Lot valley, which has siliceous terraced rows on its hillsides, and on its bordering plateaux, composed of limestone and clay of the tertiary geological eras.

In the O Ribeiro Denomination of Origin, there is a winemaking tradition of growing vines under a high-density plantation framework (8,920 vines/ha) and maintaining its vegetative cycle under rainfed conditions.
Currently, viticulture is advancing to plantation frames in which the density is considered medium (5,555 vines/ha), thus allowing mechanized work to be carried out for vineyard management operations. Although, the application of irrigation applied proportionally to the needs of the vegetative cycle of the vine, is a factor that increasingly helps a good development of the vine compared to the summer period, with increasingly uncertain weather forecasts.

Viticulture has spread to unexpected locations, such as high-altitude terrain. Among these, high-altitude viticulture has captured considerable attention, not only for the uniqueness of its products and landscapes but also because it offers an effective response to climate changes
The aim of this study is to analyse and compare wineries that used Piwi varieties (acronym for the German Pilzwiderstandfähig, i.e., cryptogame-resistant) at high altitudes (between 500 and 920 m a.s.l.) with the traditional non-mountainous viticulture model.

Terroir zoning studies have to manage the heterogeneity and complexity of the landscape properties and processes. The varying geology is one of the main landscape properties conditioning the spatial variability of terroirs.