Douro Demarcated Region Research Articles

Modelling of Wine Production Using Land Surface Temperature and FAPAR—The Case of the Douro Wine Region

The vegetative development of grapevines is orchestrated by very specific meteorological conditions. In the wine industry vineyards demand diligent monitoring, since quality and productivity are the backbone of the economic potential. Regional climate indicators and meteorological information are essential to winemakers to assure proper vineyard management. Satellite data are very useful in this process since they imply low costs and are easily accessible. This work proposes a statistical modelling approach based on parameters obtained exclusively from satellite data to simulate annual wine production. The study has been developed for the Douro Demarcated Region (DDR) due to its relevance in the winemaking industry. It is the oldest demarcated and controlled winemaking region of the world and listed as one of UNESCO’s World Heritage regions. Monthly variables associated with Land Surface Temperatures (LST) and Fraction of Absorbed Photosynthetic Active Radiation (FAPAR), which is representative of vegetation canopy health, were analysed for a 15-year period (2004 to 2018), to assess their relation to wine production. Results showed that high wine production years are associated with higher than normal FAPAR values during approximately the entire growing season and higher than normal values of surface temperature from April to August. A robust linear model was obtained using the most significant predictors, that includes FAPAR in December and maximum and mean LST values in March and July, respectively. The model explains 90% of the total variance of wine production and presents a correlation coefficient of 0.90 (after cross validation). The retained predictors’ anomalies for the investigated vegetative year (October to July) from 2017/2018 satellite data indicate that the ensuing wine production for the DDR is likely to be below normal, i.e., to be lower than what is considered a high-production year. This work highlights that is possible to estimate wine production at regional scale based solely on low-resolution remotely sensed observations that are easily accessible, free and available for numerous grapevines regions worldwide, providing a useful and easy tool to estimate wine production and agricultural monitoring.

Climate change potential effects on grapevine bioclimatic indices: A case study for the Portuguese demarcated Douro Region (Portugal)

In this work, bioclimatic parameters and indices relevant to the grapevine are estimated for the years 2000 (recent-pat), 2049 (medium-term future) and 2097 (long-term future), based on very high resolution (1 km × 1 km) MPI-WRF RCP8.5 climate simulations. The selected parameters and indices are the mean temperature during the grapevine growing season period (April to October, Tgs), the cumulative rainfall during the grapevine growing season period (Pgs), the Winkler index (WI), the Huglin heliothermic index (HI), the night cold index (CI) and the dryness index (DI). In general, a significant increase in mean temperature during the grapevine growing season period is observed, together with a significant decrease in precipitation. The recent-past WI is associated with the production of high-quality wines; the higher values predicted for the future represent intensive production of wines of intermediate quality. The HI shows the passage of a grapevine growing region considered as temperate-warm to a warm category of higher helio-thermicity. The recent-past CI indicates very cool conditions (associated with quality wines), while in the future there is a tendency for temperate or warmer nights. Finally, DI indicates an increase in water stress considered already high under the recent-past climate conditions. These results point to an increased climatic stress on the Douro region wine production and increased vulnerability of its vine varieties, providing evidence to support strategies aimed to preserve the high-quality wines in the region and their typicality in a sustainable way.

Effects of irrigation and collection period on grapevine leaf (Vitis vinifera L. var. Touriga Nacional): Evaluation of the phytochemical composition and antioxidant properties

The cultivation of grapevines (Vitis vinifera L.) has extended worldwide, with great economic importance. From this crop, we can obtain grapes for fresh consumption, raisins, juices, wine, and other derived products. The cultivation of grapevines also generates some byproducts, such as seeds, skins, wood and leaves. The leaves can be removed from the plant, as is common agricultural practice, to improve the production and quality of the grapes at certain periods in the crop cycle. In the present work, the phytochemical composition (total phenols content, hydroxycinnamic acids derivatives and flavonols) and antioxidant potential (reducing power, ABTS and DPPH radical scavenging capacity) of grapevine leaves from cv. Touriga Nacional were evaluated. The studied cultivar was under three severities of regulated deficit irrigation (RDI60, RDI40, and RDI20; providing 60, 40 and 20% of reference evapotranspiration, respectively) and non-irrigation (NI; exclusively rain-fed), in a vineyard located in the Demarcated Douro Region (Portugal). The leaves were collected at three different phenological stages: veraison, maturation, and grape harvest. For the first time, the interactions between different irrigation regimes and the collection period were evaluated on grapevine leaves. The results obtained for the phytochemical composition revealed that increasing irrigation reduced total phenols content, hydroxycinnamic acids derivatives, and flavonols in all of the phenological stages studied. For instance, compared to that of the control treatment (NI), the total phenols content reduced 19% in RDI20 (from 189 mg GAE g−1 to 153 mg GAE g−1), 28% in RDI40 (136 mg GAE g−1), and 33% in RDI60 (127 mg GAE g−1). The antioxidant activity suffered a reduction when the irrigation amount was increased for all assays. Additionally, the antioxidant activity suffered a reduction over time, presenting higher values in veraison. For harvest sampling, the loss of antioxidant activity was more notable, with EC50 values varying between 0.092 mg mL−1 (NI) and 0.187 mg mL−1 (RDI60). Altogether, the results suggest that grapevine leaves are a potential source of natural compounds with valuable antioxidant properties that could be explored by the pharmaceutical, chemical and food industries.

Wine productivity per farm size: A maximum entropy application

The size of a farm is one of the factors that influence its productivity, in an ambiguous relationship that is often discussed in the industrial economy. In Portugal, the Demarcated Douro Region (DDR) is characterized by very small farms. Usually, this trend is considered a limitating factor in the profitability of the wine farms. In order to assess the correctness of this sentence, the variation of wine productivity per land size, from 2010 to 2016, was studied in the DDR, considering its three distinctive areas: Baixo Corgo, Cima Corgo and Douro Superior. The farms were categorized in nine different size ranges; as these variables outnumber the available seven observations, the Generalized Maximum Entropy (GME) estimator was used, since it suits the need to solve an ill-conditioned problem. GME was applied with the MATLAB (MATrix LABoratory) software along with the Bootstrap technique. According to the simulations, larger farms (with an area greater than 20 ha) on Douro Superior and Cima Corgo reveal higher marginal productivity given the current state of the region. On the other hand, Baixo Corgo's results suggest that medium-sized farms (with area ranges between 2 and 5 ha) display higher marginal increments to the region wine productivity.

Is a biofix necessary for predicting the flight phenology of Lobesia botrana in Douro Demarcated Region vineyards?

The European grapevine moth, Lobesia botrana (Denis and Schiffermüller), is among the most economically important vineyard pests in European and Mediterranean areas. Predicting the insect's flight phenology during the growing season is critical to improve Integrated Pest Management (IPM) tactics through better timing of sampling or control operations. The aim of this study was to characterize the flight phenology of L. botrana in Douro Demarcated Region (DDR) in Portugal, as well as to develop degree-day (DD) models for predicting main pest flights, based on data of male catches in sex pheromone traps and temperature data recorded over a 20-year period. Nonlinear models based on Boltzmann regression equations were developed using the cumulative percentage of male catches and accumulated DD, considering two starting points for this accumulation, a biofix (first male catch) and a calendar date (January 1st), both using 7.3°C and 33°C as lower and upper thresholds, respectively. The results obtained suggest that the cumulative percentage of L. botrana catches and accumulated DD are highly related, using both events as starting points for DD accumulation, although, in the case of the second and third flights, the best correlations were obtained using the model developed from January 1st. Although the use of a biofix seems to improve model's accuracy, from the practical point of view and considering large scale application for an IPM strategy, the use of a fixed calendar date (January 1st) should be preferred. These results could be useful in timing L. botrana control measures, especially biorational pesticides applications that require accurate information on insect phenology to be effective.

Modelling the Terroir of the Douro Demarcated Region, Portugal

The Douro Demarcated Region (DDR) is one of the main winemaking regions in Portugal. Viticulture is tied to the Douro region, having a strong impact on the local economy. This mountainous region, characterized by the slopes of the Douro Valley, provides a vast range of environmental characteristics for winegrapes. Different climatic conditions, soil characteristics, topography, varieties and practices comprise the Douro terroirs, resulting in the uniqueness of the wines produced. In the current study, an assessment of the homogeneous viticultural zones is proposed for the Douro, by integrating different terroir elements (thermal, hydric, soils, topography and vegetation), using state-of-the-art very-high resolution datasets (1-km) and a large number of variables. A multivariate zoning was carried out using a principal component analysis (PCA) and a subsequent clustering. A geospatial assessment of the terroir elements was also performed separately for each sub-region in the DDR. The connections of the different terroirs prevailing at a given location were also innovatively assessed. This zoning may promote a more appropriate selection of vineyard sites, the selection of more locally-adapted varieties and rootstocks and the adoption of appropriate viticultural practices. The present study may be a standard methodology that can be applied to other winemaking regions worldwide.

Efficiency of wine grape growers at farm level: a case study

To determine the key variables of the vineyard efficiency is imperative to account the combined effects of the inputs interactions since they have implications on the overall final production. This paper estimates the productive efficiency of a wine-farm sample from the Douro Demarcated Region (DDR) while identifies economic, social and environmental indicators that characterizes the DDR grape production system. The data was collected by face-to-face surveys performed at farm level to build a pilot study. The majority of the sampled twenty farms are dedicated to mountain viticulture and mainly feature the cordon (simple and double) training system. Through the Data Envelopment Analysis (DEA) method, the productive efficiency of the sampled was performed and the results clinched different efficiency scores. The main explanation is related to the heterogeneity of the adopted production system. In addition, they revealed how grape producers could improve their productive efficiency by adopting particular practices and identifying the key factors of their system.

Ants (Hymenoptera: Formicidae) and Spiders (Araneae) Co-occurring on the Ground of Vineyards from Douro Demarcated Region

This study, held in vineyards from Douro Demarcated Region, aimed to: a) identify the communities and main functional groups of spiders and ants; b) check patterns of co-occurrence between the two communities; and c) evaluate the impact of ground cover and adjacent non-crop habitats in the proximity of vineyards, on the two communities. Samplings were done using pitfall trapping. Twenty species of ants and 44 species of spiders were identified, which included respectively three and nine Iberian endemic species. Aphaenogaster gibbosa (Latreille 1798), Aphaenogaster iberica Emery 1908, Cataglyphis hispanica (Emery 1906), Cataglyphis iberica (Emery 1906), Messor barbarus (L. 1767) and Tapinoma nigerrimum (Nylander 1856) totalized 71.21% of ants. Alopecosa albofasciata (Brullé 1832), Callilepis concolor Simon 1914, Eratigena feminea Simon 1870, Zodarion alacre (Simon 1870) and Zodarion styliferum (Simon 1870) accounted for 38% of spiders. Abundance of both ant-mimicking and ant-eating spiders were positively correlated with Formicinae, while only ant-eating spiders showed positive correlation with Myrmicinae ants. All genera/ species of ant-associated spider were associated with one or more genera/ specie of ants. The abundance of specialist spiders was higher in areas where abundance of ants was also higher. Sheet web weavers spiders were found to be positively correlated with the percentage of ground cover. The present study a) stresses that vineyard agroecosystem support a rich assemblage of ants and spiders evincing that wine production and species conservation is possible and b) the co-occurrence between some species of this two groups is not determined by random patterns.

Long-term application of the organic and inorganic pesticides in vineyards: Environmental record of past use

Areas such as Douro Demarcated Region (Portugal), where vineyards are frequently located on steep slopes of narrow valleys, can be particularly sensitive to runoff and erosion processes. These particular conditions are expected to enhance the transport of pollutants, acting as a potential source of contamination to freshwater systems. The intense vine cultivation in this region includes decades of pesticides application, that have resulted in the accumulation of these chemicals and its degradation products in the vineyards soils and sediments. Residues of several pesticides related to agricultural activities were found in soils, with older vineyards showing higher levels of Cu and banned insecticides (such as DDT). The metabolite 4,4-DDE was the compound found at higher levels in soils and in sediments. The relatively high levels in more recent sediments suggest that soils are still a source of contamination. Levels of currently used pesticides were low, which is related with their physicochemical properties, the application period, and climacteric conditions.

Daily prediction of seasonal grapevine production in the Douro wine region based on favourable meteorological conditions

Background and Aims The cooperative wineries of the Douro demarcated region (DDR) have a major socio-economic role within the winemaking sector. The existing network of regional wineries provides an organisational basis for the wine market of the DDR, contributing to the sustainability of the sector. Given this strategic importance, the present research aims to develop an innovative grape production model (PGP) targeted at regional wineries. Methods and Results For the development of the PGP model, the relationships between daily historic meteorological conditions and grape production for three wineries within the DDR (Mesao Frio, Favaios and Freixo de Espada a Cinta) were analysed. The model runs on a daily time step, comparing the thermal/hydric conditions in a given year against the average conditions in high and low production years. Results establish site-specific linkages between favourable (unfavourable) weather conditions and high (low) grapevine production. Relatively, cool pre-flowering temperature and relatively warm conditions during berry development tend to favour wine production. Furthermore, higher production is typically found in years with higher than average precipitation level until flowering. The correlation between PGP model outputs and grapevine production at the three wineries ranges from 0.68 ≤ r ≤ 0.84. Conclusions Decision makers from the DDR may indeed take advantage of the information provided by the PGP model. Daily updated knowledge of potential grape production enables wineries to timely plan and optimise harvest and postharvest procedures. Significance of the Study The PGP model may be regarded as a useful tool to implement cost-effective winery management, thus bringing added value to stakeholders and decision makers of the Portuguese winemaking sector.

Multivariate clustering of viticultural terroirs in the Douro winemaking region

The Douro Demarcated Region (DDR) is one of the most important winemaking regions in Portugal. Viticulture is historically and culturally tied to the DDR, having a strong impact on the local economy. This mountainous region, characterized by the steep slopes of the Douro Valley, provides a wide range of environmental characteristics for grapevine growth. Different climatic conditions, soil profiles, topography, grapevine varieties and management practices comprise the DDR terroir , resulting in the distinctiveness of the wines produced. In the present study, an assessment of the homogeneous zones of interest for viticultural activities is proposed for the DDR, by integrating different terroir elements (thermal, hydric, soils, topography and vegetation), using state-of-the-art high resolution datasets (1 km) and a large number of variables/indices. A multivariate zoning was carried out using a principal component analysis and a subsequent clustering methodology. A geospatial assessment of the terroir elements was also performed separately for each type of vegetation covering the DDR. The inter-connections of the different terroir elements that exist at a given location, were also innovatively assessed. The zoning may promote a more appropriate selection of vineyard sites, the selection of more locally-adapted varieties and rootstocks and the adoption of appropriate viticultural practices and management planning. After assessing the terroir conditions that exist at the current vineyard locations, possible expansion zones within the DDR were also evaluated. The present study may also be used as an archetypal methodology that can be applied to other winemaking regions worldwide.

Intangible cultural heritage and sustainable development in the Douro Demarcated Region (Northern Portugal): the cases of Cambres and Parada do Bispo

When talking of rural spaces, we usually mean peripheral areas with a range of problems, but whose potential and dynamics for revitalisation are evident. This is the case of the Douro Demarcated Region (DDR), home to an idyllic landscape of countless terraces on slopes laden with vines as well as a unique architectural, human and cultural heritage. Nevertheless, the obstacles to its development escalate, ranging from the environmental and landscape structure to the economic, social and cultural. In this paper, from a wide range of problems afflicting the region, we intend to focus on the cultural component, particularly the intangible one, highlighting the strategic role of the popular festivities and pilgrimages in the rural sustainable development.

Wine and cultural heritage. The experience of the Alto Douro Wine Region

The Demarcated Douro Region is one of the oldest demarcated wine regions, and the largest and the most heterogeneous mountainous wine region in the world. Viticulture covers 44,000ha, and since 2001 an area covering 24,600ha has been designated as the most representative territory of the Demarcated Douro Region, the Alto Douro Wine Region. This region is included in the list of World Heritage Sites as an evolving and living cultural landscape. The Demarcated Douro Region fits the terroir model, as its economy is based on wine (Porto wine and Douro still wines), supplemented by tourism. During recent decades, both activities have witnessed deep and structural changes, with consequences for the maintenance of the traditional characteristics of the cultural landscape that drove the UNESCO classification. With this issue in mind, the goal of this paper is to describe the recent evolution of the main economic activities of the Demarcated Douro Region. In particular, we aim to deepen the knowledge about the preferences of Portuguese visitors towards the Alto Douro Wine Region and its attributes, thus determining those that deserve preservation and, consequently, public attention. The results of a mixed logit model show that visitors assign highest utility to the preservation of vineyards supported by schist walls, followed by the agglomerations and the characteristic mosaic nature of the landscape. Additionally, respondents who are richer, employed, better educated, better informed regarding the culture of the site and more influenced by the listing are more willing to participate in preserving the cultural heritage of the region.

Terroir da Região Demarcada do Douro: um estudo de caso

In the Demarcated Region of Douro (DRD), sub-region of Cima-Corgo, there is a set of producing estates where existed an empirical perception that the wine produced in different areas have also a distinctive character, and those areas might be defined as terroir. An experimental work was set up in two closely located areas, where that perception existed, and a large number of grapevines of ‘Touriga Franca’, ‘Touriga Nacional’ e ‘Tinta Roriz’ were under observation to determine the characteristics of their production and of their musts, their adaptability to each location and to define each location as a distinctive terroir. It was measured the individual production of each grapevine and the respective pruning weight. The musts were chemically analyzed. Each location can be considered a terroir, the grapevine varieties showed different adaptability to each location, and the management of the vineyards must be adjusted to each place and variety.

The Douro Region: Wine and Tourism

The Demarcated Douro Region (DDR) dates from 1756, when it was recognized as one of the first demarcated regions in the world. The DDR economic activities fit the terroir model and are based on wine and tourism. Both activities have witnessed deep and structural changes along the last three decades, with influence in the current socio-economic performance of the region. The objective of this paper is to present the recent evolution of the DDR wine filiere and tourism. The Port wine continues to be the star product of DDR, with almost 90% being exported. However, along the last decade the still wines evolved from being almost unknown to a position of a national and international recognition in market niches. The tourism in Douro region is connected to the wine filiere and tends to be structured under two dominant influences: the river and the terroir .

The Douro wine region: a cluster approach

The globalization of the wine industry needs to be perceived as a challenge and an opportunity to innovate by traditional European producers’ countries, like Portugal, characterized by a terroir model, that is, an economic structure supported by a large number of grape growers, small and medium wine firms and high public regulation, to compete in international markets. Using a cluster approach, this article presents the case of the most important Portuguese wine region, the Demarcated Douro Region (DDR), which is a strong reference of terroir and known for producing Port wine. To increase its competitiveness in the world wine market, the DDR needs to evolve from an organized to an innovative cluster.

Innovation in wine SMEs: the Douro Boys informal network

Globalisation needs to be perceived by wine small and medium enterprises (SMEs) located in wine regions characterised by a terroir model as a challenge and an opportunity to innovate. The aim of this paper is to present a business strategy that can be adopted by wine SMEs located in regions with high production costs and where tradition and innovation are relevant factors to be introduced in the decision process. To achieve this goal, the case of five small wine producers (Douro Boys), located in the Portuguese conservative Douro Demarcated Region (DDR), that are adopting an informal horizontal network is presented. The conducted analysis allows us to conclude that Douro Boys is a very simple and informal structure of prospectors, with a high culture of innovation, searching for niches in international wine markets.

Innovation in wine SMEs: the Douro Boys informal network

Globalisation needs to be perceived by wine small and medium enterprises (SMEs) located in wine regions characterised by a terroir model as a challenge and an opportunity to innovate. The aim of this paper is to present a business strategy that can be adopted by wine SMEs located in regions with high production costs and where tradition and innovation are relevant factors to be introduced in the decision process. To achieve this goal, the case of five small wine producers (Douro Boys), located in the Portuguese conservative Douro Demarcated Region (DDR) that are adopting an informal horizontal network is presented. The conducted analysis allows us to conclude that Douro Boys is a very simple and informal structure of prospectors, with a high culture of innovation, searching for niches in international wine markets.

Automatic detection of bunches of grapes in natural environment from color images

Despite the benefits of precision agriculture and precision viticulture production systems, its rate of adoption in the Portuguese Douro Demarcated Region remains low. We believe that one way to raise it is to address challenging real-world problems whose solution offers a clear benefit to the viticulturist. For example, one of the most demanding tasks in wine making is harvesting. Even for humans, the environment makes grape detection difficult, especially when the grapes and leaves have a similar color, which is generally the case for white grapes. In this paper, we propose a system for the detection and location, in the natural environment, of bunches of grapes in color images. This system is able to distinguish between white and red grapes, and at the same time, it calculates the location of the bunch stem. The system achieved 97% and 91% correct classifications for red and white grapes, respectively.

Climate-related risks on agriculture in demarcated Douro region

Climate-related risks on agriculture in demarcated Douro region