Percorrer por autor "Lopes, Myriam"
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- 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.
- 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.
- 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.
- Grapevine bioclimatic indices in relation to climate change: a case study in the Portuguese Douro Demarcated RegionPublication . Blanco-Ward, Daniel; Monteiro, Alexandra; Lopes, Myriam; Borrego, Carlos S.; Silveira, Carlos; Miranda, Ana Isabel; Viceto, Carolina; Rocha, Alfredo; Ribeiro, A.C.; Andrade, João Verdial; Feliciano, Manuel; Castro, João Paulo; Barreales, David; Carlos, Cristina; Peixoto, CarlosClimate 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 13-21ºC. This study focuses on the temporal variability of three grapevine bioclimatic indices, which are commonly used as part of the Geoviticulture Multicriteria Climatic Classification System (MCC) to classify the climate of wine producing regions worldwide. Dynamical downscaling of MPI-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). Results indicate significant shifts towards warmer and dryer conditions during the growing season and higher night temperatures during the grape ripening period. An assessment on the statistical significance of the differences between the recent-past and the future scenarios and the potential impact on wine production in the study area is performed. 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.
- Ozone effects on Douro vineyards under climate changePublication . Ascenso, Ana; Gama, Carla; Silveira, Carlos; Viceto, Carolina; Rocha, Alfredo; Lopes, Myriam; Miranda, Ana IsabelTropospheric ozone (O3) levels in southern Europe have an increasing tendency, in close relation with the higher incidence of hot summers and heatwaves. Given that O3 is one of the most damaging pollutants for vegetation, known to affect productivity and quality of crops, it is necessary to develop more rigorous and consistent methods of risk assessment that consider climate change conditions. Studying the O3 deposition over the Douro Demarcated Region (DDR), which is one of the most productive wine areas in Portugal, and assessing its potential effects under a climate change scenario, was the purpose of this study. To that end, the chemical transport model CHIMERE, with a spatial resolution of 1 km2, fed by meteorological data from the WRF model, was applied for a recent past climate (2003 to 2005) and future mid-term (2049 and 2064) and long-term (2096 and 2097) scenarios. Simulations for future climate were performed considering: (i) only the climate change effect, and (ii) the effect of climate change together with future air pollutant emissions. The assessment of the potential damage in terms of wine productivity and quality (sugar content) was performed through analysis of O3 deposition and the application of concentration–response functions, based on AOT40 values. Modeling results show that a reduction in emission of O3 precursors can successfully decrease AOT40 levels in the DDR, but it is not enough to accomplish the European Commission target value for the protection of vegetation. If the emissions remain constant, the exposure–response functions indicate that, in the long-term, AOT40 levels could worsen wine productivity and quality.
- Physiological response of the grapevine cultivars Touriga Nacional and Touriga Franca to increasing summer stress conditions in the Douro RegionPublication . Ribeiro, A.C.; Barreales, David; Andrade, João Verdial; Rodrigues, M.A.; Blanco-Ward, Daniel; Monteiro, Alexandra; Lopes, Myriam; Borrego, Carlos S.; Silveira, Carlos; Viceto, Carolina; Rocha, Alfredo; Feliciano, Manuel; Castro, João Paulo; Miranda, Ana IsabelThe behaviour of the cultivars Touriga Nacional and Touriga Franca (Vitis vinifera L.), was studied under increasing summer stress conditions across Douro valley in the Demarcated Region of Douro - Portugal. The Douro region is divided into three climatic subregions: Baixo Corgo (BC), Cima Corgo (CC), and Douro Superior (DS) whose weather characteristics are presented and discussed in this study. In the Douro valley temperature increases and precipitation decreases from West (Baixo Corgo) to East (Douro Superior). Growing season precipitation has a mean value of 193 mm, representing 30% of the annual total (624 mm). Low precipitation values along with high temperatures and high radiation exposure give rise to situations of intense summer water and thermic stress, particularly in the Cima Corgo and Douro Superior subregions. The main objective of this study was to characterize the physiological response of non-irrigated grapevine cultivars Touriga Nacional and Touriga Franca growing under different summer stress conditions in the Douro region, during 2017 growing season. At veraison and ripeness stages, predawn and stem water potential showed a significant trend decrease from BC vines located in Régua to DS vines located in Almendra. Stomatal conductance, net CO2 assimilation rate, transpiration rate followed seasonal patterns similar to water potential. There was a marked reduction in these parameters from the lower to the higher dry site.
- Sintese ConclusivaPublication . Miranda, Ana Isabel; Rocha, Alfredo; Ribeiro, A.C.; Silveira, Carlos; Blanco-Ward, Daniel; Ascenso, Ana; Lopes, Myriam; Borrego, Carlos S.Este livro apresenta os principais resultados do projeto DOUROZONE, que teve como objetivo avaliar o efeito do ozono troposférico nas vinhas da Região Demarcada do Douro, em clima presente e clima futuro. Efetuaram-se simulações de clima e de ozono troposférico, com uma elevada resolução espaço-temporal. As simulações climáticas, para o clima histórico recente (1986-2005), futuro de médio prazo (2046-2065) e de longo prazo (2081-2100), indicam um aumento generalizado da temperatura máxima, média e mínima na RDD. A estas alterações de temperatura está associado o aumento de ondas de calor (em intensidade, duração e frequência) e a diminuição de ondas de frio (em duração e frequência). No que se refere a alterações de precipitação, prevê-se uma diminuição média anual e para o período do verão, mas no que se refere ao período do inverno a tendência é de aumento dos valores em praticamente toda a RDD. Note-se ainda a redução do número de dias consecutivos com precipitação e o aumento do número de dias consecutivos secos.