Browsing by Author "Ribeiro, A.C."
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- Adapting almond production to climate change through deficit irrigation and foliar kaolin application in a mediterranean climatePublication . Barreales, David; Capitão, Susana dos Anjos; Bento, Albino; Casquero, Pedro Antonio; Ribeiro, A.C.Irrigation is the best strategy to reduce the adverse effects of water stress on almond trees [Prunus dulcis (Mill) D.A. Web] and improve their productivity. However, in the current context of climatic change, in which the amount of water available for irrigation is increasingly limited, deficit irrigation (DI) strategies have become essential in the almond orchards of southern Europe. Other practices, such as the foliar application of reflective compounds, are being implemented. A three-year experiment (2019–2021) was set in a factorial design in which the effect of regulated deficit irrigation and foliar kaolin spray was evaluated on physiological (predawn leaf water potential, relative water content, leaf area, leaf gas exchange, and chlorophyll fluorescence) and agronomic parameters (yield, yield components, and water use efficiency (WUE)). The treatments include full irrigation (FI), which received 100% of ETc (crop evapotranspiration) during all irrigation seasons; regulated deficit irrigation (RDI), which received 100% of ETc until the kernel-filling stage, reducing the application to 35% ETc during the kernel-filling stage until harvest; and both irrigation regimes combined with kaolin application and two cultivars, Constantí and Vairo. More negative water potential values were observed in the RDI treatments compared to the FI treatments. There were no significant differences in the stomatal conductance, photosynthetic rate, or transpiration rate between treatments with RDI and FI, demonstrating the almond tree’s good adaptation to irrigation reduction in the kernel-filling stage. The two cultivars had different responses in cumulative yield throughout the three years of the trial. The cv. Constantí did not present significant differences between the FI and RDI treatments, translating into improved WUE. In contrast, the cv. Vairo suffered a reduction in accumulated performance in the RDI treatments with respect to the FI. The foliar application of kaolin did not present differences in yield and very few in the physiological activity of the almond trees. With the results obtained, we can suggest that under the conditions of our experiment, the combination of RDI and the kaolin foliar application can help save irrigation water and produce almonds more sustainably.
- 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).
- Alterações climáticas e agriculturaPublication . Goncalves, Dionisio; Figueiredo, Tomás de; Ribeiro, A.C.A evolução do clima nas últimas décadas colocou o problema das mudanças climáticas e os seus impactes, em particular na agricultura, nas agendas políticas nacionais e internacionais. Neste contexto,faz-se wna abordagem às alterações climáticas ao longo dos últimos 1000 anos, referindo o período de clima óptimo da alta idade media, a pequena idade do gelo dos séculos XVI a XIX, 0 aquecimento do século XX ate aos nossos dias, com a ocorrência do arrefecimento das décadas de 1960 e 1970, que se designou por Global Cooling. Referem-se as principais consequências nos sistemas de Agricultura, relacionadas com o acréscimo da incerteza no regime da precipitação e com o aumento da temperatura e seus efeitos nos estados fenológicos.
- Análise do efeito de ilha de calor urbano na cidade de BragançaPublication . Menezes, Gabriella de Ornelas; Gonçalves, Artur; Ribeiro, A.C.; Feliciano, Manuel; Bineli, Aulus RobertoNas áreas urbanas, os edifícios e superfícies alteram as condições climáticas locais, criando um clima urbano. O Efeito de Ilha de Calor Urbano é a maior representação da relação entre cidade e clima e se dá pelo aumento da temperatura na área urbana face a área rural. Esse efeito varia no espaço e no tempo, atuando de maneira diferente nas diversas áreas da cidade e ao longo do dia e do ano, além de apresentar alterações de acordo com as condições meteorológicas. O presente estudo tem como referência uma rede de 23 sensores localizados no espaço urbano, periurbano e rural da cidade de Bragança, no extremo nordeste de Portugal. Os locais de monitorização foram definidos a partir do conceito de Zona Climática Local. Com o desenvolvimento deste trabalho, procurou-se analisar o clima urbano com a finalidade de caracterizar o Efeito de Ilha de Calor Urbano e sua relação com as características do espaço urbano, considerando que o estudo incidiu sobre dados do ano de 2013. A análise climática evidenciou a existência do Efeito de Ilha de Calor, apesar da pequena dimensão da cidade. As maiores intensidades foram registradas na classe de maior grau de urbanização. No verão a mediana da intensidade situou-se em torno de 1,5°C, embora possam ser observados valores máximos acima de 6°C enquanto no inverno a mediana caiu para menos que 1,0°C e os valores máximos não ultrapassaram 3,5°C. Os picos de intensidade de ilha de calor ocorreram poucas horas antes do nascer do sol, sendo que pela manhã observou-se o fenômeno de ilha de frio no espaço urbano.
- 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.
- Aplicação de azoto e boro ao solo e foliar em amendoalPublication . Arrobas, Margarida; Rodrigues, M.A.; Barreales, David; Pereira, Ermelinda; Afonso, Sandra; Capelo, Márcio Amaro Bueno Sorrentino; Ribeiro, A.C.Com vista a melhorar o sistema de recomendação de fertilização para a amendoeira, foi instalado um ensaio de campo em Alfândega da Fé (NE Portugal) num pomar com uma densidade de plantação de 6x4 m. O delineamento experimental consistiu na aplicação de 4 doses de N (0, 25, 50 e 100 kg N ha-1) e 4 doses de B (0, 1, 2 e 3 kg B ha-1) ao solo, suplementadas com aplicações foliares de N (3 aplicações de ureia, 0,5%, durante a estação de crescimento) ou B (duas aplicações com 0,3 kg B ha-1). Um delineamento equivalente ao anterior de aplicação de N e B ao solo foi mantido sem adubação foliar. Avaliou-se a produção de fruto e a proporção de semente (amêndoa), endocarpo e mesocarpo. Procedeu-se à determinação da concentração de alguns nutrientes nos diferentes tecidos na data de colheita e ao cálculo da exportação dos nutrientes. A aplicação de N ao solo originou diferenças significativas na produção de fruto. As doses de 0 e 25 kg N ha-1 produziram menos que as doses de 50 e 100 kg N ha-1 (5,75, 8,29, 12,59 e 12,25 kg árvore-1, respetivamente). Em média, o endocarpo representou a fração do fruto com maior massa seca, 47,1%, o mesocarpo 40,1% e a semente 12,8%. O N exportado pelo fruto variou entre 15,0 g N árvore-1 (N0) e 69,7 g N árvore-1 (N100) com diferenças significativas entre doses. A suplementação foliar com N não resultou em acréscimo produtivo significativo. A aplicação de boro ao solo não mostrou efeito significativo na produção, tendo esta variado entre 12,0 kg árvore-1 em B0 e 9,1 kg árvore-1 em B3. O mesocarpo foi responsável pela maior exportação de B. A exportação deste nutriente variou entre 177,6 (B0) e 361,8 (B3) mg árvore-1. O suplemento foliar com B não revelou efeito positivo significativo.
- Aplicação de boro na amendoeira [Prunus dulcis (Mill.) D.A. Webb.]: efeito na fisiologia e produtividade das árvoresPublication . Morais, Maria Cristina; Gonçalves, Berta C.C.; Ribeiro, A.C.; Bacelar, Eunice; Rodrigues, M.A.; Oliveira, Ivo; Prgomet, Iva; Afonso, Sílvia Martins; Bernardo, Sara; Barreales, David; Victor, D.; Silva, A.P.Nos últimos anos, tem-se assistido a um crescente interesse pela cultura da amendoeira (Prunus dulcis (Mill .) D.A.Webb.) na região de Trás-os-Montes, justificado pelo aumento de preço pago da amêndoa, ao produtor. Apesar da excelente adaptabilidade desta cultura as condições edafo-climáticas desta região, continuam a existir baixas rentabilidades devido, em parte, a instalação deficiente de muitos amendoais tradicionais de sequeiro e a adopção de técnicas de cultivo pouco adequadas. Uma das técnicas mais utilizadas para aumentar a produtividade dos amendoais é a fertilização que, na região de Trás-os-Montes, assume maior relevância dadas as carências de azoto e boro nos solos. Neste trabalho, apresentam-se os resultados do primeiro ano (2015) dos efeitos da aplicação foliar e ao solo de boro na fisiologia e na produção da amendoeira cv. Glorieta num campo de ensaio instalado em Alfandega da Fé. Foram estabelecidos 8 tratamentos com concentrações variáveis de boro ao solo e combinados com aplicação foliar do mesmo micronutriente. Na altura da colheita, foi avaliado o estado fisiológico das árvores através da medição das trocas gasosas foliares, da fluorescência da clorofila a in vivo, e de parâmetros do estado hídrico bem como quantificada a produtividade das árvores. Dos resultados obtidos ressalta que, as árvores submetidas a aplicação de boro ao solo apresentam melhor resposta fisiológica comparativamente as árvores sujeitas a aplicação combinada de boro ao solo e por via to liar, m as se m efeito significativo na produtividade. E de esperar que os efeitos da aplicação de boro sejam mais evidentes no ano seguinte ao da aplicação pelo que será necessária prosseguir os estudos para confirmar qual a aplicação de boro mais adequada para o amendoal em condições de sequeiro.
- Apple orchard frost protection with wind machine operationPublication . Ribeiro, A.C.; Melo-Abreu, J. Paulo de; Snyder, R.L.Research has shown that wind machines are more effective under conditions of strong thermal inversions. Quantitative relationships between the level of protection and inversion strength, however, are not well known, and there are few reports on the effect of fan operation on energy balance. Whether the wind machines should be started before surface cooling causes turbulence damping and atmospheric stratification or if it is possible to delay starting until just before the critical temperature occurs remains a matter of discussion. Therefore, experiments were conducted on 11 spring frost nights during the 1999 and 2000 to assess the effectiveness of a fan operation on frost protection of an apple orchard under different microclimatic conditions. The 11 frost events were characterized by light winds (0.58–1.92 m s−1) and clear skies for most of the night, resulting in an average accumulated radiative loss of 2.67 ± 0.38 MJ m−2. The air temperature increased immediately after the wind machines were started and the temperature rise depended on inversion strength. For each 1 °C increase in temperature inversion strength between 1.5 and 15 m height, wind machine operation caused a 0.3 °C increase of air temperature at a 1.5 m height within the main area affected by the fan operation. Using multiple regression, the area protected was significantly related to the temperature increase and the inversion strength. Wind machine operation reduced flower damage by 60% in 1999 and 37% in 2000. Distribution of flower damage varied spatially, and it was related to wind drift.
- 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.
- Assessing water scarcity footprint of wine production in the Alentenjo region: preliminary resultsPublication . Presumido, Pedro Henrique; Gonçalves, Artur; Saraiva, Artur; Jorge, Célia; Ribeiro, A.C.; Silvestre, José; Silva, Pedro Oliveira e; Ramôa, Sofia; Oliveira, Margarida; Feliciano, ManuelFor multiple reasons, climate change is likely to contribute to the increase in water consumption and to the deterioration of its quality. Water scarcity has been a major concern to the wine sector, given the strong impact that can it have on the vineyard productivity, wine quality and on the vineyard environment. In Portugal, there is an alarming trend in the annual mean temperature increase, as fear grows that it may aggravate water scarcity, so there is a concern that justifies the increase in the number of the studies in these scientific areas. Environmental footprint indicators have frequently been calculated through the use of life cycle approaches (LCA). The aim of this study was to evaluate the water scarcity footprint (WSF) for the production of a bottle of wine thus providing additional support for strategic decisions made in these sectors. 2. Experimental - The assessment of WSF in the wine production in the south of Portugal (Alentejo region) was based on the methodological framework defined in the ISO 14046 standard. The functional unit (UF) selected for the study was a 0.75L wine bottle. A cradle-to-gate approach was adopted in the study, and, therefore, the system under study was limited to the viticulture stage and wine production. For this WSF study, the GaBi Software (Thinkstep) was used with its professional database. The main water scarcity regional characterization factors used in this study were Water Scarcity Index, AWaRe (WULCA), and UBP. 3. Results and Discussion - The preliminary results show the difference between the proposed methodologies for water scarcity footprint assessment when applied to wine production in the Alentejo region of Portugal. The water scarcity footprint methods may give different results depending on their assumptions. Furthermore, the preliminary assessment identified that upstream and downstream processes were both relevant to the WSF. With the identification of hotspots and the implementation of actions for water conservation and saving it is expected that it will minimize the environmental impact of winegrowing and reduce the vulnerability of the vine-wine chain. 4. Conclusions - The WSF should be included as an indicator to determine the uses and consumptions of water in wine production as it is a useful decision-making tool for both companies and governmental authorities. In addition, the results from this work may prompt the comparison between water footprints in regions of Portugal and the rest of the world.