Terroir 1996 banner
IVES 9 IVES Conference Series 9 Bench terraces, agricultural practices and viticultural zoning in Ribeira Sacra (Galicia, Spain).

Bench terraces, agricultural practices and viticultural zoning in Ribeira Sacra (Galicia, Spain).

Abstract

L’aire d’AOC Ribeira Sacra s’étend sur plus de 200 km au large des versants escarpés du Miño et du Sil, dans la Galice (Espagne). C’est une région viticole avec des caractéristiques bien particulières que complique leur zonage viticole. Elle est désormais une région dans laquelle les vignobles sont placés sur les versants fortement inclinés (parfois la pente est supérieure à 60% ), aménages en terrasses très étroites (les gradins n’ont souvent pas plus d’un mètre de large) avec des murs en pierres sèches qui ont derrière eux au moins un bon millénaire d’existence. Ces terrasses constituent un exemple remarquable de formations anthropiques très efficaces au point de minimiser l’érosion du sol et de conduire à formation de microclimats particulièrement adaptés aux besoins de la vigne.
Par leurs caractéristiques on peut parler de véritables anthrosols et d’un zonage initial lié au procès de construction des terrasses. Du point de vue pédologique la région est bien homogène, même s’il y a quelques variations en raison des conditions particulières d’orographie, de la nature de la roche-mère (granites, gneiss, ardoises), des facteurs locaux d’exposition (de l’ouest à sud-est), de l’altitude (200 à 450 m) et, surtout, des façons de concevoir la gestion de la fertilité chimique des sols viticoles.
D’un côté, il y a des vignes où l’entretien du sol est fait selon la manière traditionnelle, avec des apports épisodiques d’engrais végétaux : ainsi, dans de nombreux vignobles, on se contente d’épandre en couverture après la vendange, un mélange de fumier, de bois de taille, de marcs de raisin et de quelques touffes de genêts ramassées dans la lande. Le plus souvent dans ces vignobles prédominent les sols avec des teneurs en matière organique élevées (même si la matière organique est très stable et sa vitesse d’évolution est lente), sols acides et riches en aluminium échangeable (l’aluminium est souvent le plus abondant parmi les cations échangeables), à faible taux de saturation de la capacité d’échange, pauvres en potassium et avec des teneurs élevées en cuivre assimilable.
Par contre, dans le cas des vignes mieux cultivées et, surtout, dans les nouvelles plantations et les replantations, l’emploi des engrais minéraux et des amendements calciques et magnésiens est très répandu. C’est dans ces vignobles que l’on trouve des sols avec un pH neutre ou légèrement acide, une teneur en matière organique plus faible, une capacité d’échange de cations effective (CECe) plus élevée; le calcium -parfois le magnésium- sont les cations échangeables le plus couramment présents sur le complexe d’échange.
En conclusion, dans les vignobles de l’ AOC Ribeira Sacra, on peut parler d’un zonage initial associé à l’aménagement en terrasses et sur lequel se superpose un deuxième zonage (plus important au point de vue des caractéristiques chimiques des sols et du potentiel qualitatif des raisins), fonction des façons d’entretien du sol.

The particular characteristic of the Ribeira Sacra OAC in Galicia (Spain) makes complicate their viticultural zoning. In this region, vineyards are cultivated in narrow bench terraces (1 m width) on slopes up to 60%. Men along the last eight centuries, playing an important role as an effective conservation practice to prevent soil erosion, have constructed these. This practice produced an important thickening of soils, providing the development of vineyards in zones, which are characterised by their adequate microclimate.
The parent geologic materials are gneiss, granite and slate, the azimuth of the hill slopes is from south to southeast and their altitude range is from 200 to 450 m above Mediterranean Sea level. Men activities may be considered as the most important forming factor. In fact, agricultural practices acting during all this time are the most important forming factor of these soils. We observed an initial zoning of these soils derived from human activities. Furthermore, we consider that these practices correspond with the requirements of the Anthrosol FAO soil unit.
The traditional management practices that still being used include organic fertilisation and .amendment and manual cultivation up to 40 cm depth. Most relevant physicochemical properties are low pH in water and in KCI saturation extracts, high organic mater contents (with low mineralisation rate), and low base saturation percentage in the cation exchange complex, and high exchangeable aluminium and assimilable copper contents. Other farmers use lime as amendment and inorganic fertilisation that increase pH and cation exchange capacity values, and diminution of organic mater and assimilable copper content.

DOI:

Publication date: February 15, 2022

Issue:  Terroir 2002

Type: Article

Authors

José M.G. QUEIJEIRO, Eugenio L. PERIAGO, Manuel ARIAS and Benedicto SOTO

Area de Edafología y Química Agricola. FacuJtad de Ciencias de Ourense, As Lagoas s/n 32004. España

Contact the author

Keywords

Ribeira Sacra, Espagne, terrasses, entretien du sol, zonage
Ribeira Sacra, Spain, bench terraces, viticultural zoning, cultural practices

Tags

IVES Conference Series | Terroir 2002

Citation

Related articles…

Influence of weather and climatic conditions on the viticultural production in Croatia

The research includes an analysis of the impact of weather conditions on phenological development of the vine and grape quality, through monitoring of four experimental cultivars (Chardonnay, Graševina, Merlot and Plavac mali) over two production years. In each experimental vineyard, which were evenly distributed throughout the regions of Slavonia and The Croatian Danube, Croatian Uplands,

Modeling island and coastal vineyards potential in the context of climate change

Climate change impacts regional and local climates, which in turn affects the world’s wine regions. In the short term, these modifications rises issues about maintaining quality and style of wine, and in a longer term about the suitability of grape varieties and the sustainability of traditional wine regions. Thus, adaptation to climate change represents a major challenge for viticulture. In this context, island and coastal vineyards could become coveted areas due to their specific climatic conditions. In regions subject to warming, the proximity of the sea can moderate extremes temperatures, which could be an advantage for wine. However, coastal and island areas are particular prized spaces and subject to multiple pressures that make the establishment or extension of viticulture complex.
In this perspective, it seems relevant to assess the potentialities of coastal and island areas for viticulture. This contribution will present a spatial optimization model that tends to characterize most suitable agroclimatic patterns in historical or emerging vineyards according to different scenarios. Thanks to an in-depth bibliography a global inventory of coastal and insular vineyards on a worldwide scale has been realized. Relevant criteria have been identified to describe the specificities of these vineyards. They are used as input data in the optimization process, which will optimize some objectives and spatial aspects. According to a predefined scenario, the objectives are set in three main categories associated with climatic characteristics, vineyards characteristics and management strategies. At the end of this optimization process, a series of maps presents the different spatial configurations that maximize the scenario objectives.

Adaptation to soil and climate through the choice of plant material

Choosing the rootstock, the scion variety and the training system best suited to the local soil and climate are the key elements for an economically sustainable production of wine. The choice of the rootstock/scion variety best adapted to the characteristics of the soil is essential but, by changing climatic conditions, ongoing climate change disrupts the fine-tuned local equilibrium. Higher temperatures induce shifts in developmental stages, with on the one hand increasing fears of spring frost damages and, on the other hand, ripening during the warmest periods in summer. Expected higher water demand and longer and more frequent drought events are also major concerns. The genetic control of the phenotypes, by genomic information but also by the epigenetic control of gene expression, offers a lot of opportunities for adapting the plant material to the future. For complex traits, genomic selection is also a promising method for predicting phenotypes. However, ecophysiological modelling is necessary to better anticipate the phenotypes in unexplored climatic conditions Genetic approaches applied on parameters of ecophysiological models rather than raw observed data are more than ever the basis for finding, or building, the ideal varieties of the future.

Adapting the vineyard to climate change in warm climate regions with cultural practices

Since the 1980s global regime shift, grape growers have been steadily adapting to a changing climate. These adaptations have preserved the region-climate-cultivar rapports that have established the global trade of wine with lucrative economic benefits since the middle of 17th century. The advent of using fractions of crop and actual evapotranspiration replacement in vineyards with the use of supplemental irrigation has furthered the adaptation of wine grape cultivation. The shift in trellis systems, as well as pruning methods from positioned shoot systems to sprawling canopies, as well as adapting the bearing surface from head-trained, cane-pruned to cordon-trained, spur-pruned systems have also aided in the adaptation of grapevine to warmer temperatures. In warm climates, the use of shade cloth or over-head shade films not only have aided in arresting the damage of heat waves, but also identified opportunities to reduce the evapotranspiration from vineyards, reducing environmental footprint of vineyard. Our increase in knowledge on how best to understand the response of grapevine to climate change was aided with the identification of solar radiation exposure biomarker that is now used for phenotyping cultivars in their adaptability to harsh environments. Using fruit-based metrics such as sugar-flavonoid relationships were shown to be better indicators of losses in berry integrity associated with a warming climate, rather than solely focusing on region-climate-cultivar rapports. The resilience of wine grape was further enhanced by exploitation of rootstock × scion combinations that can resist untoward droughts and warm temperatures by making more resilient grapevine combinations. Our understanding of soil-plant-atmosphere continuum in the vineyard has increased within the last 50 years in such a manner that growers are able to use no-till systems with the aid of arbuscular mycorrhiza fungi inoculation with permanent cover cropping making the vineyard more resilient to droughts and heat waves. In premium wine grape regions viticulture has successfully adapted to a rapidly changing climate thus far, but berry based metrics are raising a concern that we may be approaching a tipping point.

Long-term drought resilience of traditional red grapevine varieties from a semi-arid region

In recent decades, the scarcity of water resources in agriculture in certain areas has been aggravated by climate change, which has caused an increase in temperatures, changes in rainfall patterns, as well as an increase in the frequency of extreme phenomena such as droughts and heat waves. Although the vine is considered a drought-tolerant specie, it has to satisfy important water requirements to complete its cycle, which coincides with the hottest and driest months. Achieving sustainable viticulture in this scenario requires high levels of efficiency in the use of water, a scarce resource whose use is expected to be severely restricted in the near future. In this regard, the use of drought-tolerant varieties that are able to maintain grape yield and quality could be an effective strategy to face this change. During three consecutive seasons (2018-2020) the behavior in rainfed regime of 13 traditional red grapevine varieties of the Spain central region was studied. These varieties were cultivated in a collection at Centro de Investigación de la Vid y el Vino de Castilla-La Mancha (IVICAM-IRIAF) located in Tomelloso (Castilla-La Mancha, Spain). Yield components (yield, mean bunch and berry weight, pruning weight), physicochemical parameters of the musts (brix degree, total acidity, pH) and some physiological parameters related with water stress during ripening period (δ13C, δ18O) were analysed. The application of different statistical techniques to the results showed the existence of significant differences between varieties in their response to stressful conditions. A few varieties highlighted for their high ability to adapt to drought, being able to maintain high yields due to their efficiency in the use of water. In addition, it was possible quantify to what extent climate can be a determinant in the δ18O of musts under severe water stress conditions.