Terroir 2004 banner
IVES 9 IVES Conference Series 9 Study and valorization of vineyards “terroirs” of A.O.C. Cahors (Lot, France)

Study and valorization of vineyards “terroirs” of A.O.C. Cahors (Lot, France)

Abstract

In the current context of market competition and consumption evolution, it is necessary to produce wines of a genuine typicity. The Terroir represents an unique and irreproducible inheritance that can be valorized through the origin and the sensory characteristics of the wines.
Since 1989, the Expérimental Association of « la Ferme Départementale d’Anglars-Juillac » has led research and experimentation on vineyard terroirs, aimed at direct valorization for the winegrowers. The objective is to know (1) the wine-producing potentials of each terroir of the Cahors Appellation, for the principal vine grape cultivars of the Appellation: Malbec N or Cot N or Auxerrois N, (2) the vine behaviour on these terroirs and (3) to valorize this knowledge through technology, agronomy and enological procedures adapted to each terroir.
Cartography of the whole A.O.C. Cahors has been realized (22000ha). Nine terroirs have been identified according to the type of soil and the landscape situation: alluvial terraces of the Lot, “grèzes”, calcareous hillsides, high calcareous plateaus (eventually with marl), and red clays from sidérolithique formations. Agronomic and enological studies of a representative parcel of each terroir have been done since 1994. Pedological pits have also been done with physical and chemical analyses of each described horizon. Each year, maturity controls are carried out on these parcels; each is separately vinified with the same protocol. Wines are analyzed and tasted.
Results show that qualitative terroirs exist on alluvial terraces of the Lot, as well as on high calcareous plateaus. It is not the chemical nature (acid or calcareous) of the soil but the thickness of the soil which determines the quality of a terroir, in relation with the regularity of vine hydrous nutrition. For all that, some terroirs seem well adapted to produce vintage wines, whereas other terroirs seem more adapted to produce regional wines or wines for blending.
This study provides an agronomic and enological basis for advising wine-growers, in order to lead each terroir to its qualitative optimum: adaptation of the cultural practices, especially for new plantations (choice of the rootstock, soil management); adaptation of the method of vinification according to the terroir. The wine-grower has to take care of the terroir, the quality of the grape harvested and the wine. This study has led to a qualitative improvement of A.O.C. Cahors wines. The Cahors Appellation is now experiencing an infatuation for the most qualitative terroirs.
In the future, the start-up of the hierarchical system of the A.O.C. Cahors terroirs and the creation of vintage wines, will allow a large communication on wine quality and typicity, favorable to the whole Appellation Cahors wine business.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

Francis Laffargue (1), Elisabeth Besnard (1) and Marc Garcia (2)

1) Association d’Expérimentation, Ferme Départementale, 46140 Anglars-Juillac, France
2) ENSAT, Centre de Viticulture-Œnologie de Midi-Pyrénées, Avenue de l’Agrobiopole, Auzeville-Tolosane, BP 107 F, 31320 Castanet-Tolosane Cedex, France

Contact the author

Tags

IVES Conference Series | Terroir 2004

Citation

Related articles…

A spatial explicit inventory of EU wine protected designation of origin to support decision making in a changing climate

Winemaking areas recognized as protected designations of origin (PDOs) shape important economic, environmental and cultural values that are tied to closely defined geographic locations. To preserve wine products and wine-growing practices adopted in different PDOs these areas are strictly regulated by legal specifications. However, quality viticulture is increasingly under pressure from climate change, which is altering the local conditions of many winegrowing areas. Therefore, maintaining traditional wine products will require the adoption of tailored adaptation strategies, including possible changes in the legal regulation of protected wines. To this end, it is necessary to have a comprehensive knowledge on PDOs including their extension, products and allowed practices. While there have been efforts to build databases that summarize the characteristics for individual wine PDO areas and to quantify the related effects of climate change, much information is still included only in the official documentation of the EU geographical indication register and has never been collected in a comprehensive manner. With this study we aim at filling this gap by building a spatial inventory of European wine PDOs that supports decision making in viticulture in the context of climate change. To map and characterize European wine PDOs, we analysed their legal documents and extracted relevant information useful for climate change adaptation. The output consists of a comprehensive geographical dataset that identifies the boundaries of all 1200 European wine PDOs at unprecedented spatial resolution and includes a set of legally binding regulations, such as authorized vine varieties, maximum yields and planting density. The inventory will allow researchers to analyse the impacts of climate change on European wine PDOs and support decision makers in developing tailored adaptation strategies. This includes, among others, the evaluation of new vineyard site selection, the expansion of cultivated varieties or the authorization of irrigation in vineyards.

Organic recycled mulches in sustainable viticulture: assessment of spontaneous plants communities and weed coverage

In recent years, developing more efficient and sustainable viticulture management has been essential due to the impact of climate change in semiarid regions. For this reason, the use of recycled organic mulching (ROM) in the vineyard has become an interesting strategy to cope with water stress, isolated soil from extreme temperatures and improving soil humidity, control the presence of weeds and therefore reduce the inputs of herbicides and improve soil fertility. This work aimed to analyse the effect of three different organic mulches [straw (S), grape pruning debris (GPD) and spent mushroom compost (SMC)] and two traditional soil management techniques [herbicide (H) and interrow (IN)] on weed coverage and the spontaneous plant communities’ presence. Data sampling was collected throughout the vine vegetative cycle of 2021 in La Rioja, Spain. The different soil management techniques had a clear effect on weed coverage and his development during the vine vegetative cycle. SMC and H were the treatments with the highest and the lowest coverage percentage, respectively. IN had a delayed weed emergence at the beginning of the vine vegetative cycle, but finally it reached maximum values nearby SMC. GPD and S had similar effects on weed emergence, reaching 25-30% of the maximum coverage values. A total of 29 herbaceous species were identified during the vegetative cycle, some of them very isolated and occasional. Principal component analysis (PCAs) showed a good association between spontaneous species and treatments, furthermore, specific species-treatment associations were found. Moreover, three clear groups of herbaceous communities were identified by cluster analysis. This study provides interesting information about the effect of different alternative soil management on herbaceous plant coverage and weed species communities which could contribute to making more sustainable viticulture.

Effects of graft quality on growth and grapevine-water relations

Climate change is challenging viticulture worldwide compromising its sustainability due to warmer temperatures and the increased frequency of extreme events. Grafting Vitis vinifera L.

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"...

Co-design and evaluation of spatially explicit strategies of adaptation to climate change in a Mediterranean watershed

Climate change challenges differently wine growing systems, depending on their biophysical, sociological and economic features. Therefore, there is a need to locally design and evaluate adaptation strategies combining several technical options, and considering the local opportunities and constraints (e.g. water access, wine typicity). The case study took place in a typical and heterogeneous Mediterranean vineyard of 1,500 ha in the South of France. We developed a participatory modeling approach to (1) conceptualize local climate change issues and design spatially explicit adaptation strategies with stakeholders, (2) numerically evaluate their effects on phenology, yield and irrigation needs under the high-emissions climate change scenario RCP 8.5, and (3) collectively discuss simulation results. We organized five sets of workshops, with in-between modeling phases. A process-based model was developed that allowed to evaluate the effects of six technical options (late varieties, irrigation, water saving by reducing canopy size, adjusting cover cropping, reducing density, and shading) with various distributions in the watershed, as well as vineyard relocation. Overall, we co-designed three adaptation strategies. Delay harvest strategy with late varieties showed little effects on decreasing air temperature during ripening. Water constraint limitation strategy would compensate for production losses if disruptive adaptations (e.g. reduced density) were adopted, and more land got access to irrigation. Relocation strategy would foster high premium wine production in the constrained mountainous areas where grapevine is less impacted by climate change. This research shows that a spatial distribution of technical changes gives room for adaptation to climate change, and that the collaboration with local stakeholders is a key to the identification of relevant adaptation. Further research should explore the potential of adaptation strategies based on soil quality improvement and on water stress tolerant varieties.