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…

Short-term relationships between climate and grapevine trunk diseases in southern French vineyards

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Towards adaptation to climate change in Rioja: Quality evaluation of wines obtained from Grenache x Tempranillo selections

The wine sector is of great relevance and tradition in Mediterranean countries, however, it may be most susceptible to climate change. In recent years, wine production is facing changes worldwide, both at environmental as well as commercial levels, due to global warming and the shift in consumers’ preferences. Wine growers and wine makers are in search of solutions that allow to face these new challenges. One of the most promising initiatives in the long term is the introduction of new plant materials, specifically intraspecific hybridizations between premium varieties that may improve traditional germplasm in its adaptation to climate change. These inter-varietal crosses have the potential to generate quality wines, whilst maintaining the regional typicity, and constitute an attractive alternative for the consumer due to their sensory attributes. In this study, we have evaluated wines from 29 intraspecific Garnacha x Tempranillo hybrids in two different locations, with the aim to assess their oenological potential and sensory attributes. Thirteen of the selections were white and 16 were red. Microvinifications were conducted with two or three replications depending on grape availability. Conventional oenological parameters were determined for all wines. The sensory evaluation and hedonic scores were given by five experts. Red selections obtained higher quality scores than white ones. Among the white selections with higher quality scores, GT-41 Varea and GT-159 Varea outstand, due to their high total acidity and high malic acid content. Regarding red selections, GT-57 Varea and GT-57 UR were perceived as higher in quality, highlighted for their moderate alcoholic and high anthocyanin content. Our results indicate that intraspecific hybridization may be a powerful tool for adapting traditional cultivars to climate change in Rioja.

Evaluation of climate change impacts at the Portuguese Dão terroir over the last decades: observed effects on bioclimatic indices and grapevine phenology

In the last decades the growers of the Portuguese Dão winegrowing region (center of Portugal) are experiencing changes in climate that are influencing either grape phenology berry health and ripening. Aiming to study the relationships between climate indices (CI), seasonal weather and grapevine phenology, in this work long-term climate and phenological data collected at the experimental vineyard of the Portuguese Dão research centre between 1958 and 2019 (61 years) for the red variety Touriga Nacional, was analyzed. The trends over time for the classical temperature-based indices (Growing Season Temperature – GST -, Growing Degree Days – GDD, Huglin Index – HI and Cool Night Index – CI) presented a significantly positive slope while the Dryness Index (DI) showed a negative trend over the last 61 years. Regarding grapevine phenology, an average advance of 4.5 days per decade in the harvest day was observed throughout the last 61 years. Consequently, the weather conditions during the ripening period have changed, showing an increasing trend over time in the average temperature (higher magnitude in the maximum than in the minimum temperature) and a decrease in the accumulated rainfall. A regression analysis showed that ~50% of harvest date variability over years was explained by the temperature-based indices variability. These observed effects of climate change on bioclimatic indices and corresponding anticipation of harvest date can still be considered advantageous for the Dão terroir as it allows to achieve an optimal berry ripening before the common equinox rains and, therefore, avoid the potential negative impacts of the rainfall on berry health and composition.

Underpinning terroir with data: rethinking the zoning paradigm

Agriculture, natural resource management and the production and sale of products such as wine are increasingly data-driven activities. Thus, the use of remote and proximal crop and soil sensors to aid management decisions is becoming commonplace and ‘Agtech’ is proliferating commercially; mapping, underpinned by geographical information systems and complex methods of spatial analysis, is widely used. Likewise, the chemical and sensory analysis of wines draws on multivariate statistics; the efficient winery intake of grapes, subsequent production of wines and their delivery to markets relies on logistics; whilst the sales and marketing of wines is increasingly driven by artificial intelligence linked to the recorded purchasing behaviour of consumers. In brief, there is data everywhere!

Opinions will vary on whether these developments are a good thing. Those concerned with the ‘mystique’ of wine, or the historical aspects of terroir and its preservation, may find them confronting. In contrast, they offer an opportunity to those interested in the biophysical elements of terroir, and efforts aimed at better understanding how these impact on vineyard performance and the sensory attributes of resultant wines. At the previous Terroir Congress, we demonstrated the potential of analytical methods used at the within-vineyard scale in the development of Precision Viticulture, in contributing to a quantitative understanding of regional terroir. For this conference, we take this approach forward with examples from contrasting locations in both the northern and southern hemispheres. We show how, by focussing on the vineyards within winegrowing regions, as opposed to all of the land within those regions, we might move towards a more robust terroir zoning than one derived from a mixture of history, thematic mapping, heuristics and the whims of marketers. Aside from providing improved understanding by underpinning terroir with data, such methods should also promote improved management of the entire wine value chain.

Metabolomic discrimination of grapevine water status for Chardonnay and Pinot noir

Water status impact in viticulture has been widely explored, as it strongly affects grapevine physiology and grape chemical composition. It is considered as a key component of vitivinicultural terroir. Most of the studies concerning grapevine water status have focused on either physiological traits, or berry compounds, or traits involved in wine quality. Here, the response of grapevine to water availability during the ripening period is assessed through non-targeted metabolomics analysis of grape berries by ultra-high resolution mass spectrometry. The grapevine water status has been assessed during 2 consecutive years (2019 & 2020), through carbon isotope discrimination on juices from berries collected at maturity (21.5 brix approx.) for 2 Vitis vinifera cv. Pinot noir (PN) and Chardonnay (CH). A total of 220 grape juices were collected from 5 countries worldwide (Italy; Argentina; France; Germany; Portugal). Measured δ13C (‰) varied from -28.73 to -22.6 for PN, and from -28.79 to -21.67 for CH. These results also clearly revealed higher water stress for the 2020 vintage. The same grape juices have been analysed by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS) and Liquid Chromatography coupled to Mass Spectrometry (LC-qTOF-MS), leading to the detection of up to 4500 CHONS containing elemental compositions, and thus likely tens of thousands of individual compounds, which include fatty acids, organic acids, peptides, phenolics, also with high levels of glycosylation. Multivariate statistical analysis revealed that up to 160 elemental compositions, covering the whole range of detected masses (100 –1000 m/z), were significantly correlated to the observed gradients of water status. Examples of chemical markers, which are representative of these complex fingerprints, include various derivatives of the known abscisic acid (ABA), such as phaesic acid or abscisic acid glucose ester, which are significantly correlated with higher water stress, regardless of the variety. Cultivar-specific behaviours could also be identified from these fingerprints. Our results provide an unprecedented representation of the metabolic diversity, which is involved in the water status regulation at the grape level, and which could contribute to a better knowledge of the grapevine mitigation strategy in a climate change context.