Browsing by Author "Blanco-Ward, Daniel"
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- Agronomic and physiological behavior of two Portuguese grapevine cultivars in distinct climatic sub-regions of Douro (Portugal)Publication . Ribeiro, A.C.; Barreales, David; Andrade, João Verdial; Rodrigues, M.A.; Blanco-Ward, DanielThe agronomic and physiological behaviour of the Portuguese grapevine cultivars Touriga Nacional and Touriga Franca (Vitis vinifera L.), were 3810-193 studied under distinct climatic conditions across Douro valley in the Demarcated Region of Douro - Portugal. The Douro region is divided into three climatic sub-regions: Baixo Corgo, Cima Corgo, and Douro Superior whose weather characteristics are presented and discussed in this study. In the Douro valley, low precipitation values along with high temperatures and high radiation exposure give rise to situations of intense summer water and thermic stress. These conditions are particularly more severe in the Cima Corgo and Douro Superior sub-regions. The main objective of this study was to characterize the agronomic and physiological response of the cultivars Touriga Nacional and Touriga Franca growing under natural rainfed field conditions, during 2017 growing season. The experiment was conducted in commercial vineyards located in the Demarcated Douro Region (RDD). Three study areas were considered in this study: (i) Baixo Corgo (BC): Quinta da Pacheca in Régua (Lat. 41°08'28.8"N, Long. 7°49'01.2"W, elevation 136 m); Cima Corgo (CC): Quinta do Porto in Pinhão (Lat. °10'21.1"N, Long. 7°34'13.8"W, elevation 174 m) and Douro Superior (DS): Quinta da Leda in Almendra (Lat. (41°01'31.6"N, Long. 7°00'55.7"W, elevation 235 m). Physiological (stem water potential, stomatal conductance, net CO2 assimilation rate, transpiration rate and intrinsic water use efficiency) and agronomic (leaf area index (LAI); pruning weigh, productivity and berry composition) parameters were monitored on vines of both cultivars, growing under different summer water stress conditions: severe (DS) moderate (CC) and weak (BC).
- Analysis of climate change indices in relation to wine production: a case study in the Douro region (Portugal)Publication . Blanco-Ward, Daniel; Monteiro, Alexandra; Lopes, Myriam; Borrego, Carlos S.; Silveira, Carlos; Viceto, Carolina; Rocha, Alfredo; Ribeiro, A.C.; Andrade, João Verdial; Feliciano, Manuel; Castro, João Paulo; Barreales, David; Carlos, Cristina; Peixoto, Carlos; Miranda, Ana IsabelClimate change is of major relevance to wine production as most of the wine-growing regions of the world, in particular the Douro region, are located within relatively narrow latitudinal bands with average growing season temperatures limited to 13–21◦C. This study focuses on the incidence of climate variables and indices that are relevant both for climate change detection and for grape production with particular emphasis on extreme events (e.g. cold waves, storms, heat waves). Dynamical downscaling ofMPI-ESM-LR global data forced with RCP8.5 climatic scenario is performed with the Weather Research and Forecast (WRF) model to a regional scale including the Douro valley of Portugal for recent-past (1986–2005) and future periods (2046– 2065; 2081–2100). The number, duration and intensity of events are superimposed over critical phenological phases of the vine (dormancy, bud burst, flowering, v´eraison, and maturity) in order to assess their positive or negative implications on wine production in the region. An assessment on the statistical significance of climatic indices, their differences between the recent-past and the future scenarios and the potential impact on wine production is performed. Preliminary results indicate increased climatic stress on the Douro region wine production and increased vulnerability of its vine varieties. These results will provide evidence for future strategies aimed to preserve the high-quality wines in the region and their typicality in a sustainable way.
- Assessing the risk of tropospheric ozone phytotoxic effect on Southern European Mediterranean environments: a review with emphasis on vineyardsPublication . Blanco-Ward, Daniel; Miranda, Ana Isabel; Silveira, Carlos; Ascenso, Ana; Gama, Carla; Monteiro, Alexandra; Lopes, Myriam; Borrego, Carlos S.; Ribeiro, A.C.; Feliciano, Manuel; Castro, João Paulo; Andrade, João Verdial; Barreales, David; Viceto, Carolina; Rocha, Alfredo; Carlos, CristinaTropospheric ozone in Southern Europe has an increasing tendency in association with a greater incidence of warm summers and heatwaves. As there is already much evidence of the negative effects that current ambient ozone has on vegetation, there is a need for consistent risk assessment methods. Ozone plant exposure-based parameters have been used extensively to support decision-making. However, these parameters have been also criticised, as they do not relate with the actual dose of ozone entering the plant. Moreover, in Mediterranean environments, they often overestimate the risk as thresholds are exceeded without corresponding evidence of damaging effects. To overcome these limitations, dose-based approaches were developed. These approaches have a stronger biological basis as they are based on estimates of the amount of ozone molecules that diffuse into the leaf cells through the stomata. However, they have also limitations, as detoxification processes or non-stomatal uptake are not often taken into consideration. This work presents a review regarding ambient ozone effects on vegetation and the indices used to assess phytotoxic risk in southern European Mediterranean plant communities and crops. Emphasis is given to the grapevine as three southern European countries (Spain, Italy and Portugal) are major wine producers concentrating more than 20% of the area under grapevines globally. These countries hold a long winemaking tradition associated to renowned denominations of origin (DOs). Therefore, there is concern regarding climate change as a potential threat to wine typicity in these areas, most of the work focusing on atmospheric variables, bioclimatic and climate change indices only. Results from the DOUROZONE project are presented with the aim to analyse the implications climate change can have in a significant Portuguese wine region such as the Douro Demarcated Region (DDR) including ozone-related indices as a novelty among other more frequently used bioclimatic and climate change indices.
- Assessment of tropospheric ozone phytotoxic effects on the grapevine (Vitis vinifera L.): A reviewPublication . Blanco-Ward, Daniel; Ribeiro, A.C.; Paoletti, Elena; Miranda, Ana IsabelThe grapevine (Vitis vinifera L.) is a crop with great cultural, economic and ecological relevance for Mediterranean environments besides being the fruit crop with largest acreage and economic value at the global scale. Its exposure to high levels of tropospheric ozone (O3) can result in phytotoxic effects and thus it is important to comprehensively re-evaluate these effects as well as related processes. A review of the validity and limitations of the standards used for the protection of vegetation in relation to ambient O3, the state-of the-art knowledge on O3 phytotoxic effects on the grapevine and the available means to assess its impact are presented and discussed. It is concluded that wide regions in the world, mainly between latitudes 30◦ and 50◦ N, where the grapevine has been traditionally cultivated, are exposed to O3 concentrations that can affect both the yield and quality of the grape. Recently reported studies for global cultivars such as Cabernet Sauvignon or Merlot, along publicly available maps on O3 standards to protect vegetation at the European and global scale, indicate potential yield reductions in the range of 20–31% and the quality of the grape can also be affected by reductions of total polyphenols in the range of 15–23% for these areas. Although a tendency to reduce ambient O3 levels has been registered since 2000 in the western European Mediterranean basin, the flux of O3 into the grapevine leaves could still exceed critical levels with phenological advancement driven by the increase of temperatures or interaction between O3 and other climatic variables such as drought or high summer light intensities. Higher O3 exposures are reported in western United States of America and eastern China, with this last region maintaining an increasing tendency in summer ambient O3 levels. It is still necessary to adopt common experimental and monitoring protocols to establish grapevine-specific O3 relationships and critical levels, as there is not yet a coherent and shared database for detailed risk assessment for this crop.
- Atlas Digital DOUROZONEPublication . Monteiro, Alexandra; Rocha, Alfredo; Viceto, Carolina; Ascenso, Ana; Gama, Carla; Blanco-Ward, Daniel; Silveira, Carlos; Ribeiro, A.C.; Castro, João Paulo; Miranda, Ana Isabel; Gonçalves, Luís JorgeUm dos objetivos do projeto DOUROZONE compreendeu a elaboração de um atlas digital para apresentação e divulgação dos seus principais resultados, recorrendo a uma plataforma on-line, de modo a uma melhor e mais eficaz disseminação de informação relativa à avaliação do risco de exposição ao ozono das vinhas da Região Demarcada do Douro, em clima presente e futuro. Este atlas digital – alojado em http://dourozone.web.ua.pt/atlas e com acesso direto através do site do projeto: http://dourozone.web.ua.pt - disponibiliza uma estrutura em árvore, com 3 opções possíveis de visualização, que permitem avaliar a situação do clima presente e o impacte de alterações climáticas (futuro de médio e de longo prazo)
- Avaliação do risco de efeito fitotóxico do ozono troposférico em ambientes Mediterrânicos do sul de Europa: uma revisão com ênfase na cultura da vinhaPublication . Blanco-Ward, Daniel; Miranda, Ana Isabel; Silveira, Carlos; Ascenso, Ana; Gama, Carla; Monteiro, Alexandra; Lopes, Myriam; Borrego, Carlos S.; Ribeiro, A.C.; Feliciano, Manuel; Castro, João Paulo; Andrade, João Verdial; Barreales, David; Viceto, Carolina; Rocha, Alfredo; Carlos, CristinaExiste uma preocupação crescente com os possíveis efeitos das alterações climáticas na indústria vitivinícola em relação à produtividade da vinha e à qualidade do vinho. Um estudo de campo que envolveu medições de ozono superficial, medições meteorológicas e observações fenológicas da vinha foi realizado numa área de produção de vinhos de renome internacional, a Região Demarcada do Douro (RDD). A avaliação dos possíveis efeitos fitotóxicos sobre a qualidade e a produção do vinho foi estimada com base num índice cumulativo de exposição ao ozono (o AOT40) e num parâmetro de dose de ozono fitotóxica (o POD6). Os padrões espaciais desses parâmetros também foram calculados através da aplicação de um modelo químico de transporte atmosférico (CHIMERE) e um modelo de deposição seca de ozono (EMEP). Os principais resultados indicam que a exposição da vinha a níveis de ozono da magnitude dos registados pode causar perdas até 10% na produtividade, porém esta relação requer estudos adicionais para uma mais correta integração das condições ambientais específicas da RDD, especialmente no que diz respeito ao comportamento das castas cultivadas na região, nas metodologias de cálculo destes parâmetros.
- Climate change impact on a wine-producing region using a dynamical downscaling approach: Climate parameters, bioclimatic indices and extreme indicesPublication . Blanco-Ward, Daniel; Monteiro, Alexandra; Lopes, Myriam; Borrego, Carlos S.; Silveira, Carlos; Viceto, Carolina; Rocha, Alfredo; Ribeiro, A.C.; Andrade, João Verdial; Feliciano, Manuel; Castro, João Paulo; Barreales, David; Neto, Jorge; Carlos, Cristina; Peixoto, Carlos; Miranda, Ana IsabelClimate change is of major relevance to wine production as most of the winegrowing regions of the world are located within relatively narrow latitudinal bands with average growing-season temperatures (GSTs) limited to 13–21 C. This study focuses on the incidence of climate variables and indices that are relevant both for climate change assessment and for grape production, with emphasis on grapevine bioclimatic indices and extreme events (e.g., cold waves, storms, heatwaves). Dynamical downscaling of European Reanalysis-Interim and Max Planck Institute Earth System low-resolution global simulations forced with a Representative Concentration Pathway 8.5 (RCP8.5) greenhouse gas emission scenario was performed with the Weather Research and Forecast (WRF) model to a regional scale including the Douro Valley of Portugal for recent-past (1986–2005) and future periods (2046–2065, 2081–2100). The number, duration and intensity of events were superimposed over critical phenological phases estimated by using a specific local grapevine varietal phenological model in order to assess their positive or negative implications for wine production in the region. An assessment of the relevance of climate parameters and indices and their progression in recent-past and future climate scenarios with regard to the potential impact on wine production was performed. Results indicate a positive relation between higher growing-season heat accumulations and greater vintage yields. A moderate incidence of very hot days (daily maximum temperature above 35 C) and drought from pre-véraison phenological conditions have a positive association with vintage ratings. However, the mid- and long-term WRF-MPI RCP8.5 future climate scenarios reveal shifts to warmer and drier conditions, with the mean GST not remaining within range for quality wine production in the long-term future climate scenario. These results indicate potential impacts that suggest a range of strategies to maintain wine production and quality in the region.
- Climate change potential effects on grapevine bioclimatic indices: a case study for the Portuguese Demarcated Douro Region (Portugal)Publication . Blanco-Ward, Daniel; Ribeiro, A.C.; Barreales, David; Castro, João Paulo; Andrade, João Verdial; Feliciano, Manuel; Viceto, Carolina; Rocha, Alfredo; Carlos, CristinaIn this work bioclimatic parameters and indices relevant to the grapevine are estimated for the years 2000 (past-recent), 2049 (medium-term future) and 2097 (long-term future), based on high resolution (1 km x 1 km) MPI-WRF RCP 8.5 climate simulations. The selected parameters and indices are mean temperature during the grapevine period (April to October), cumulative rainfall during the grapevine period, Winker index (IW), Huglin heliothermic index (IH), night cold index (IF) and dryness index (IS). In general, a significant increase in mean temperature during the grapevine period is observed, together with a significant decrease in precipitation. The present IW 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 IH show the passage of a growing region of the vine considered as hot-temperate to a warm category of higher helio-thermicity. At present, IF indicates very cool conditions (associated with quality wines), while in the future there is a tendency for temperate nights. Finally, IS indicates an increase in water stress considered already high in the present climate. An assessment on the statistical significance of climatic indices, their differences between the historical and the future scenarios and the potential impact on wine production is performed. Preliminary results indicate increased climatic stress on the Douro region wine production and increased vulnerability of its vine varieties. These results will provide evidence for future strategies aimed to preserve the high-quality wines in the region and their typicality in a sustainable way.
- Climate change potential effects on grapevine bioclimatic indices: a case study for the Portuguese demarcated Douro Region (Portugal)Publication . Blanco-Ward, Daniel; Ribeiro, A.C.; Barreales, David; Castro, João Paulo; Andrade, João Verdial; Feliciano, Manuel; Viceto, Carolina; Rocha, Alfredo; Carlos, Cristina; Silveira, Carlos; Miranda, Ana IsabelIn 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.
- Efecto del riego deficitario en los cultivares Touriga Nacional y Touriga Franca (Vitis vinifera L.) en la Región Demarcada del Duero (Portugal)Publication . Barreales, David; Andrade, João Verdial; Feliciano, Manuel; Castro, João Paulo; Rodrigues, M.A.; Blanco-Ward, Daniel; Miranda, Ana Isabel; Silveira, Carlos; Monteiro, Alexandra; Lopes, Myriam; Borrego, Carlos S.; Viceto, Carolina; Rocha, Alfredo; Ribeiro, A.C.El principal factor ambiental que limita la producción de uvas en cantidad y calidad en la mayoría de las regiones productoras de vino del mundo es la falta de agua en determinados momentos de su ciclo de cultivo. Así, se están buscando estrategias para mitigar el efecto de la sequía. El riego deficitario (DI) es una de las estrategias que mejores resultados proporciona. Con este tipo de riego se pretende aportar agua en momentos puntuales y en dosis bajas. Este estudio fue realizado durante el año 2017 en una viña comercial situada en la “Região Demarcada do Douro” (Portugal), en dos cultivares, Touriga Nacional y Touriga Franca. Se usó el riego deficitario, 25% de la evapotranspiración de referencia, en comparación con el secano. El objetivo fue evaluar el efecto del riego deficitario en los parámetros fisiológicos y agronómicos de las plantas así como en la producción y la calidad de las uvas y mostos. Los resultados obtenidos indican un gran estrés hídrico en las plantas de secano, reduciéndose la conductancia estomática y la fotosíntesis neta. El riego aumento la producción de uva sin reducir significativamente los parámetros cualitativos del mosto.