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- Life-cycle greenhouse gas assessment of Portuguese chestnutPublication . Rosa, Diana; Figueiredo, Filipa; Castanheira, Érica Geraldes; Feliciano, Manuel; Maia, Filipe; Santos, José M.R.C.A.; Silva, A.P.; Trindade, Henrique; Freire, FaustoThis paper presents a life-cycle greenhouse gas (GHG) assessment of various chestnut production systems in northern Portugal. Life-cycle models and inventories were implemented for three chestnut cultivation systems and two processing lines (fresh and frozen chestnut). The overall GHG intensity ranged between 0.4-2.7 (fresh) and 0.6-2.9 (frozen) kg CO2eq kg-1 harvested chestnut. The cultivation contribution to the overall GHG intensity varied considerably (from 0.36 to 2.69 kg CO2eq kg-1 harvested chestnut) mainly due to different yields and input requirements (diesel and fertilizers) among the three chestnut cultivation systems analysed. The GHG emissions associated with chestnut processing ranged between 0.05 (for fresh chestnut, mostly from propane consumption) and 0.23 kg CO2eq kg-1 harvested chestnut (for frozen chestnut, mainly due to electricity consumption). The results demonstrate the importance of cultivation management practices, in particular an efficient use of fertilizers in order to minimize the GHG intensity of Portuguese chestnut.
- Gestão ambiental de uma empresa do sector vinícolaPublication . Lopes, Andreia; Gonçalves, Artur; Feliciano, ManuelO setor vinícola apresenta grande relevância para a economia nacional devido à sua elevada capacidade exportadora, contribuindo de forma positiva para o saldo da balança comercial. As preocupações de carácter ambiental e com o desenvolvimento sustentável do negócio assumem-se crescentemente como áreas fulcrais para a competitividade das organizações do sector. É neste contexto que surge este estudo, que contempla a avaliação do desempenho ambiental de uma organização de produção de vinhos, com o objetivo de identificar os aspetos ambientais significativos, analisar a conformidade legal, delinear estratégias e ações que permitam uma melhoria do seu desempenho. No âmbito desta análise aplicaram-se indicadores de ecoeficiência, contribuindo para o delineamento de objetivos e metas de redução dos consumos de energia, água e matérias-primas e, cumulativamente, reduzir a produção de resíduos, efluentes e ruído. Após a identificação dos aspetos e impactes ambientais e a aplicação de um método para o cálculo do índice de significância, foi possível identificar os aspetos ambientais significativos da organização, nomeadamente o consumo de energia elétrica, o consumo de água, a utilização de embalagens de vidro e cartão, os efluentes líquidos e a utilização de gases fluorados nos sistemas de refrigeração.
- Análise de um sistema de aquecimento urbano no campus do Instituto Politécnico de BragançaPublication . Remor, Paula; Azevedo, João; Arioli, Rafael; Feliciano, ManuelUm dos sistemas de aquecimento que se vem expandindo é o Aquecimento Urbano (District Heating), que possibilita o aquecimento de um conjunto de edifícios a partir de uma única central de aquecimento. O presente trabalho teve por objetivo avaliar a possibilidade de converter o atual sistema de aquecimento do ar ambiente dos vários edifícios do Campus do Instituto Politécnico de Bragança, Portugal, num sistema de Aquecimento Urbano alimentado a biomassa florestal na forma de pellets. Deste modo, recorreu-se ao software RETScreen para modelar o sistema atual de aquecimento do campus assim como para construir modelos de sistemas de aquecimento alternativos com os quais foi posteriormente comparado em termos energéticos e ambientais. Os resultados indicam que um sistema de aquecimento urbano utilizando biomassa como combustível é uma alternativa com benefícios a nível das emissões de Gases de Efeito Estufa e em termos de custos energéticos. Assim sendo, a conversão do sistema atual do IPB a gás natural num sistema a biomassa deve ser equacionada como uma solução viável num futuro próximo.
- Respiratory deposition dose of PM2.5 and PM10 during night and day periods at an urban environmentPublication . Cipoli, Yago Alonso; Furst, Leonardo; Feliciano, Manuel; Alves, CéliaInhalation of particulate matter (PM) has been extensively associated with the worsening and onset of cardiorespiratory diseases, being responsible for millions of deaths annually. Assessment of PM deposition in the human respiratory tract is critical to better understand the health risks from environmental exposure of vulnerable age groups. In this study, PM2.5 and PM10 day-night monitoring campaigns during the cold season were carried out in Braganca, Portugal. The multiple-path particle dosimetry (MPPD) model was used to quantify total and regional depositions in the human respiratory tract for four different age groups: infant (3 months), child (9 years), adult (21 years) and elderly (65 years). The results showed that concentrations for both PM fractions were higher during the night, a period marked by the burning of biomass for residential heating. Regional deposition fractions (DF) for PM2.5 were in the ranges 17-38% (head), 4-14% (tracheobronchial) and 20-28% (pulmonary), while for PM10 were 24-67% (head), 4-27% (tracheobronchial) and 12-22% (pulmonary). Children and the elderly were found to be the most vulnerable groups to PM deposition, especially for the TB and H regions, respectively. The lifetime cancer and non-cancer risks associated with exposure to PM2.5 exceeded the recommended limits, especially for children <10 years old. These findings provide useful information to alert authorities to the need to take action to reduce the pollution burden and protect the health, in particular of those most susceptible.
- A portable measurement device based on phenanthroline complex for iron determination in waterPublication . Fernandes, Samuel; Tlemcani, Mouhaydine; Bortoli, Daniele; Feliciano, Manuel; Lopes, Maria ElminaIn this work, a newly developed self-contained, portable, and compact iron measurement system (IMS) based on spectroscopy absorption for determination of Fe2+ in water is presented. One of the main goals of the IMS is to operate the device in the field as opposed to instruments commonly used exclusively in the laboratory. In addition, the system has been tuned to quantify iron concentrations in accordance with the values proposed by the regulations for human consumption. The instrument uses the phenanthroline standard method for iron determination in water samples. This device is equipped with an optical sensing system consisting of a light-emitting diode paired with a photodiode to measure absorption radiation through ferroin complex medium. To assess the sensor response, four series of Fe2+ standard samples were prepared with different iron concentrations in various water matrices. Furthermore, a new solid reagent prepared in-house was investigated, which is intended as a "ready-to-use" sample pre-treatment that optimizes work in the field. The IMS showed better analytical performance compared with the state-of-the-art instrument. The sensitivity of the instrument was found to be 2.5 mu g Fe2+/L for the measurement range established by the regulations. The linear response of the photodiode was determined for concentrations between 25 and 1000 mu g Fe2+/L, making this device suitable for assessing iron in water bodies.
- Seasonal variation in exposure to particulate matter among children attending different levels of education: comparison of two dosimetry modelsPublication . Charres, Isabella; Cipoli, Yago Alonso; Furst, Leonardo; Vicente, Estela D.; Casotti Rienda, Ismael; Lazaridis, Mihalis; Feliciano, Manuel; Alves, CéliaExposure to particulate matter (PM) has been associated with several adverse health outcomes. Studies indicate that children may be exposed to much higher concentrations of PM at school than in other environments. There exists very little data on the deposited dose of PM while children attend classes. This study was carried out in a school located near an industrial complex in Portugal and attended by children aged 3–12 years. Indoor PM10, PM2.5 and PM1 were measured over two seasons in classrooms representing different school year groups. Particle deposition fractions in the respiratory tract, as well as the deposited doses, were calculated using the Multiple-Path Particle Dosimetry (MPPD) and the Exposure Dose Model (ExDoM2). Both models were implemented assuming an 8-hour exposure scenario to represent the school day. In general, differences in PM concentrations were observed depending on room occupancy periods and season. The highest mean PM2.5 concentration was recorded in winter when the classroom was vacant (23.7 ± 20.5 μg m-3), while the highest mean PM10 level was observed in spring during school hours (61.7 ± 24.2 μg m-3). Regardless of the dosimetry model, the highest deposition of PM10 and PM2.5 was in the upper region, while the lowest was in the tracheobronchial (TB) region. The results indicate that deposited dose and deposition fraction in spring may be more harmful to pupils’ health than in winter. PM10 presented the highest doses, ranging from 54.2 to 128 μg and from 83.9 to 185 μg, according to MPPD and ExDoM2 estimates, respectively.
- Green space influence on thermal comfort contrasting approaches in the assessment of conditions in Bragança (Portugal)Publication . Gonçalves, Artur; Ribeiro, A.C.; Nunes, Luís; Maia, Filipe; Feliciano, ManuelGreen Spaces are regarded as elements that can help to provide thermal comfort inside cities. To evaluate this influence both climate and personal variables must be investigated and evaluated taking into account different spatial layouts. Trying to address this complex reality, two different approaches were developed, using green spaces at the city of Bragança (Portugal) as case studies: green spaces surveys, addressing users, and structured experiments, controlling both individual and climatic variables. Field surveys proven to identify a narrow range of thermal sensations, thus limiting the analysis. Data from a structured experiment, conducted in early fall conditions, show the influence of different green space locations on both meteorological variables and thermal sensations. Amongst the evaluated variables, global radiation proves to be the most relevant variable influencing the perceived thermal sensations.
- Forest landscapes and global change. New frontiers in management, conservation and restoration. Proceedings of the IUFRO Landscape Ecology Working Group International ConferencePublication . Azevedo, João (Ed.); Feliciano, Manuel (Ed.); Castro, José (Ed.); Pinto, M. Alice (Ed.)This volume contains the contributions of numerous participants at the IUFRO Landscape Ecology Working Group International Conference, which took place in Bragança, Portugal, from 21 to 24 of September 2010. The conference was dedicated to the theme Forest Landscapes and Global Change - New Frontiers in Management, Conservation and Restoration. The 128 papers included in this book follow the structure and topics of the conference. Sections 1 to 8 include papers relative to presentations in 18 thematic oral and two poster sessions. Section 9 is devoted to a wide-range of landscape ecology fields covered in the 12 symposia of the conference. The Proceedings of the IUFRO Landscape Ecology Working Group International Conference register the growth of scientific interest in forest landscape patterns and processes, and the recognition of the role of landscape ecology in the advancement of science and management, particularly within the context of emerging physical, social and political drivers of change, which influence forest systems and the services they provide. We believe that these papers, together with the presentations and debate which took place during the IUFRO Landscape Ecology Working Group International Conference – Bragança 2010, will definitively contribute to the advancement of landscape ecology and science in general. For their additional effort and commitment, we thank all the participants in the conference for leaving this record of their work, thoughts and science.
- Avaliação de fluxos de CO2 do solo de um sistema agroflorestal do Nordeste de PortugalPublication . Reis, Luciléia Barbosa; Patrício, Maria Sameiro; Diegues, Samuel Filipe da Fonseca; Poggere, Giovana; Feliciano, ManuelNo âmbito das alterações climáticas, mitigar as emissões de dióxido de carbono (CO2) é de fundamental importância para conter uma gama de fenómenos que vêm perturbando o equilíbrio natural do planeta Terra nas últimas décadas. O presente trabalho teve como objetivo avaliar os fluxos de CO2 do solo num sistema agroflorestal do Norte de Portugal, utilizando o método da caixa em diferentes condições de gestão do solo, nomeadamente com solo nu (efeito mobilização) e solo ervado (efeito não mobilização), em função de variáveis meteorológicas e edafoclimáticas. Neste contexto, foram avaliadas a variação temporal e espacial dos fluxos de CO2 de uma plantação de castanheiros em sistema agroflorestal para produção de castanha, estudando os fatores que influenciam e ou interferem no processo de trocas de carbono entre o solo e a atmosfera, em inter-relação com a gestão praticada. O Estudo abrangeu duas áreas distintas, uma não mobilizada com subcoberto vegetal permanente e uma outra área, contígua, cujo controlo da vegetação é efetuado por ação de mobilização frequentes (manutenção de solo nu). O procedimento experimental consitiu em selecionar 10 pontos de amostragem, 6 na área não mobilizada (Área A) e 4 na área mobilizada (Área B), e efetuar medições em triplicado, em cada ponto, em três momentos distintos do dia, entre março e junho de 2019. Os Fluxos de CO2 do solo foram obtidos através de um sistema portátil CO2, o LI-8100A, que integra uma unidade de controlo e análise de CO2 e vapor de água acoplado a uma câmara transparente. A humidade, a temperatura do solo e a radiação fotossinteticamente ativa foram também medidas em simultâneo, através de uma Sonda de humidade 8100-202, de um Termístor 8100-203 e de um Sensor Quântico LI-190R. Os principais resultados apontam para um valor médio do Fluxo de CO2 de -1,86 μmol m-2 s-1 para a área A e 1,93 μmol m-2 s-1para a área B, durante o mesmo período de tempo. Conclui-se que durante o período de avaliação, a área A (cobertura permanente do solo) foi um sumidouro de carbono, enquanto a área B (solo nu) atuou como fonte emissora de carbono do solo.
- Evaluation of SO2 dry deposition over short vegetation in PortugalPublication . Feliciano, Manuel; Pio, Casimiro; Vermeulen, AlexSO2 dry deposition was studied over short vegetation, in Portugal, by means of the concentration gradient method. The experimental study involved one first phase of long-term measurements carried out in a grassland and, subsequently, a second period of several 1997 intensive field campaigns performed in three places representing different climate and surface conditions. Temporal and spatial patterns of dry deposition parameters show that downward fluxes of SO2 are by some extent affected by surface processes. Median Rc varied from 140 s cm-1 to values around 200 s cm-1, in a wide range of environmental conditions. Stomatal uptake is an important sink when vegetation is biologically active, but its contribution is effectively low when compared with non-stomatal mechanisms, especially when the surface is wet. Under dry conditions Rc increases by a factor of two, but SO2 deposition rates then still are signifficant. The parameterisation of the surface resistance for SO2 proved to be difficult, but Vd derived with the Erisman parameterisation (Erisman et al., Atmos. Environ. 28 (16) (1994) 2595) compared best with measured values, at low time resolution scale and especially under moisture conditions.