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- How can a changing climate influence the productivity of traditional olive orchards? Regression analysis applied to a local case study in PortugalPublication . Silveira, Carlos; Almeida, Arlindo; Ribeiro, A.C.Nowadays, the climate is undoubtedly one of the main threats to the sustainability of olive orchards, especially in the case of rainfed traditional production systems. Local warming, droughts, and extreme weather events are some of the climatological factors responsible for environmental thresholds in relation to crops being exceeded. The main objective of this study was to investigate the influence of microclimatic variability on the productivity of traditional olive orchards in a municipality located in northeastern Portugal. For this purpose, official data on climate, expressed through agrobioclimatic indicators, and olive productivity for a 21-year historical period (2000–2020) were used to evaluate potential correlations. In addition, a comprehensive regression analysis involving the dataset and the following modeling scenarios was carried out to develop regression models and assess the resulting predictions: (a) Random Forest (RF) with selected features; (b) Ordinary Least- Squares (OLS) with selected features; (c) OLS with correlation features; and (d) OLS with all features. For the a and b scenarios, features were selected applying the Recursive Feature Elimination with Cross-Validation (RFECV) technique. The best statistical performance was achieved considering nonlinearity among variables (a scenario, R2 = 0.95); however, it was not possible to derive any model given the underlying methodology to this scenario. In linear regression applications, the best fit between model predictions and the real olive productivity was obtained when all the analyzed agro-bioclimatic indicators were included in the regression (d scenario, R2 = 0.85). When selecting only the most relevant indicators using RFECV and correlation techniques, moderate correlations for the b and c regression scenarios were obtained (R2 of 0.54 and 0.49, respectively). Based on the research findings, especially the regression models, their adaptability to other olive territories with similar agronomic and environmental characteristics is suggested for crop management and regulatory purposes.
- Health impact pathways related to air quality changes: testing two health risk methodologies over a local traffic case studyPublication . Silveira, Carlos; Ferreira, Joana; Miranda, Ana I.Air pollution causes damage and imposes risks on human health, especially in cities, where the pollutant load is a major concern, although the extent of these effects is still largely unknown. Thus, taking the busiest road traffic area in Portugal as a local case study (600 m × 600 m domain, 4 m2 spatial resolution), the objective of this work was to investigate two health risk methodologies (linear and nonlinear), which were applied for estimating short-term health impacts related to daily variations of high-resolution ambient nitrogen dioxide ( NO2) concentrations modelled for winter and summer periods. Both approaches are based on the same general equation and health input metrics, differing only in the relative risk calculation. Health outcomes, translated into the total number of cases and subsequent damage costs, were compared, and their associated uncertainties and challenges for health impact modelling were addressed. Overall, for the winter and summer periods, health outcomes considering the whole simulation domain were lower using the nonlinear methodology (less 27% and 28%, respectively). Spatially, these differences are more noticeable in locations with higher NO2 and population values, where the highest health estimates were obtained. When the daily NO2 exposure was less than 6 μg.m−3, a fact that occurred in 95% of the domain cells and in both periods, relatively small differences between approaches were found. Analysing the seasonality effect, total health impacts derived from the linear and nonlinear applications were greater in summer (around 18% in both approaches). This happens due to the magnitude and spatial variability of NO2, as the other health input metrics remained constant. This exploratory research in local scale health impact assessment (HIA) demonstrated that the use of refined input data could contribute to more accurate health estimates and that the nonlinear approach is probably the most suitable for characterising air pollution episodes, thus providing important support in HIA.
- 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.
- 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.
- 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.
- Particle-bound polycyclic aromatic hydrocarbons in a rural background atmosphere of southwestern EuropePublication . Matos, João; Silveira, Carlos; Cerqueira, Mário; Matos J.Polycyclic aromatic hydrocarbons (PAHs) are a group of organic pollutants widely distributed in the atmosphere and well known for their carcinogenic and mutagenic properties. Over the last two decades, research about atmospheric PAHs has been focused in urban and industrial areas, while less attention has been given to rural areas. This study aims to contribute to filling this gap by analyzing the levels, sources and associated health risks of particulate PAHs in a rural coastal atmosphere of southwestern Europe (Portugal). A total of 132 PM10 aerosol samples were collected over a 3-year period, from 2014 to 2016, with a high-volume sampler and analyzed for 7 PAHs by high-performance liquid chromatography. The global average of the sum of the concentrations of PAHs (ΣPAHs) was 0.320 ± 0.597 ng/m3. Benzo[b]fluoranthene was the dominant congener in the majority of aerosol samples, with an average contribution of 25% to the ΣPAHs. A seasonal trend was repeatedly observed over the study period with higher concentrations of PAHs during the autumn and winter months. The HYSPLIT model was used to examine air mass transport pathways into the sampling site, revealing that changes in the frequency of continental air mass trajectories were a key factor explaining the seasonal variation of PAHs. Model runs also indicated that fast-moving air masses were more efficient at dispersing PAHs emitted in the surrounding region than slow-moving air masses with a similar origin (marine or continental). The average concentration of benzo[a]pyrene, a powerful human carcinogen, was found to be 0.044 ± 0.098 ng/m3, approximately two orders of magnitude lower than average values previously recorded in the most polluted European atmospheres. Diagnostic ratio analysis suggested that mobile and stationary combustion sources were equally contributing to the atmospheric load of PAHs. The estimated average lifetime lung cancer risk was below the health-based guideline level, indicating a low risk of lung cancer development associated with inhalation exposure to particle-phase PAHs.
- Technological innovation in the traditional olive orchard management: advances and opportunities to the Northeastern region of PortugalPublication . Silveira, Carlos; Almeida, Arlindo; Ribeiro, A.C.In Portugal, the olive orchard is the most representative agricultural crop and one of the most impactful on the national economy. Therefore, a production structure accompanying the technological advances in this field would be expected; however, such a structure has not yet been realized, especially within traditional systems. Thus, taking northeastern Portugal as a case study, where a great expression of traditional orchards is visible, the following aspects are addressed within this paper: the region’s biophysical framework, the olive orchard’s environmental and socio- economic importance and its current management practices and associated pressures. As a result of that assessment, which demonstrates a low level of sustainability for traditional olive orchards, mainly in terms of economic viability, the most effective and simple solution is to act appropriately on factors that interfere with the crop yield, namely, irrigation and fertilization issues. With that purpose, a multiscale precision oliviculture system is also presented that is being developed in order to support decision making in traditional olive orchard management, aiming to obtain economically efficient productions based on eco-friendly cultural practices. Throughout the entire process, it is essential to ensure stakeholder engagement, in particular, olive growers, so that they recognize the effectiveness of potential measures that may avoid the reconversion/abandonment of the traditional olive production system.
- Using Analytic Hierarchy Process to Assess Beekeeping Suitability in Portuguese Controlled Areas: A First ApproachPublication . Roque, Natália; Fernandez, Paulo; Silveira, Carlos; Vilas-Boas, Miguel; Anjos, OféliaSimple Summary Beekeeping is an activity that supports agriculture and wildlife on earth, so it is very important to provide accurate information that is able to help in increasing the profitability of beekeeping and valorize pollination services. In this paper, a new methodology is proposed to assess beekeeping potential using Geographic Information Systems (GIS) and the Analytical Hierarchy Process. The proposed tool will support decision making by selecting the best apiary locations to maximize honey production and, consequently, the risks of losing bee colonies will be reduced. The Suitability map (apiary aptitude map) allows for validating the best locations for apiaries (considering the spatial and floristic resources use), and the aptitude for installing new apiaries or moving existing ones. In this sense, the application of Multi-criteria GIS Analysis, in the context of beekeeping planning, is a useful tool for the Beekeepers Association to manage honeybee resources within the territory in order to maximize their profit, and for government agencies to implement promotional measures and policies to maximize food support needs and mitigate spared diseases.Abstract Beekeeping management is greatly influenced by spatial factors (e.g., land use/land cover, roads, or electrical energy networks), so GIS are a powerful tool to overlap and relate a variety of spatial data levels and, consequently, a very useful tool for beekeeping activity planning. This study was developed within the intervention area of three controlled zones managed by Portuguese Beekeepers Associations. The methodology, based on multi-criteria decision analysis, integrates several criteria, such as hydrographic networks, road networks, soil occupation, solar radiation, and electromagnetic radiation sources. These criteria were proposed and evaluated through online questionnaires carried out with beekeepers. Concerning the selected criteria and the respective geographical data, the most relevant were land use/land cover and water availability, with a significance of 44% and 24%, respectively. The beekeeping suitability map enabled us to evaluate the degree of compliance for the actual location of apiaries, with 60% of the apiaries being installed in high potential areas. In the context of beekeeping planning, the potential of the techniques applied seems to be an important tool for optimizing the location of apiaries and the profitability of beekeeping.
- 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.
- 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)