CERNAS – CENTRO DE RECURSOS NATURAIS, AMBIENTE E SOCIEDADE
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- Greenhouse Gas Emissions and Ryegrass Yield after Application of Solid-Liquid Pig Slurry and Biochar to an Agricultural SoilPublication . Pereira, José Luís da Silva; Perdigão, Adelaide; Bonifácio, Gabriel; Figueiredo, Vitor; Marques, Francisco; Trindade, Henrique; Ferreira Wessel, DulcineiaBackground: The application of animal slurry to the soil improves its quality, as manure contains many nutrients for plants. However, this could negatively impact the environment. Objective: This field study investigated the effects of the addition of biochar after the mechanical separation of Whole pig Slurry (WS) into Solid (SF) and Liquid Fractions (LF) on Greenhouse Gases (GHG) emissions (N2O, CO2, and CH4) and ryegrass (Lolium multiflorum Lam. cv magnum) yield. Methods: Biochar (1.0 kg m-2) was applied in plots alone or together with each of the three slurries (80 kg N ha-1) in a total of eight treatments with three replications, including just soil with and without biochar as controls. Soil properties, Greenhouse Gas (GHG) fluxes, and yield were measured during theautumn/winter growing season. Results: The results showed that the addition of biochar to these three slurries significantly increased the soil pH and showed no impact on the other physicochemical properties. The GHG emissions were not significantly different between treatments with and without biochar. The N use efficiency increased significantly in SF > WS > LF, whereas no differences were observed among these three slurries with and without biochar. Conclusion: It can be concluded that the addition of biochar combined with WS or SF/LF to sandy-loam soil appears to have no impact on GHG emissions and ryegrass yield during the autumn/winter season. Overall, this finding suggests that amounts higher than 1.0 kg m-2 of biochar combined with SF may need to be applied to soil to reduce GHG emissions and nitrate leaching and increase N use efficiency and crop yield
- Eating habits and food knowledge in a sample of portuguese university studentsPublication . Guiné, Raquel; Ferreira, Manuela; Duarte, João; Nunes, Bruno; Morais, Patrícia; Sanches, Rafaela; Abrantes, RomanaThe choice to adopt a healthy diet is complex, since food choices and eating behaviours are influenced by various factors, such as biological, social, environmental, demographic and psychological aspects. The transition from secondary school to university is a critical period that involves many social and physical environmental changes, which may lead to an unhealthy lifestyle. This study investigated the eating habits, food knowledge and the level of information about a healthy diet in a sample of 670 university students in Portugal. In general, the participants had a good food knowledge and satisfactory eating habits, as well as a satisfactory level of information about a healthy diet. There were found significant differences in the participants’ food knowledge among age groups and according to the area of studies. Most of the students revealed satisfactory eating habits, with significant differences between age groups, the area of studies and the practice of high competition sport. The results pointed to the necessity of improving educational programs which can contribute to increase university students’ food knowledge and consequently improve their eating habits.
- Structural characterization of lignin from Grape Stalks (Vitis vinifera L.)Publication . Prozil, Sónia; Evtuguin, Dmitry V.; Silva, Artur M. S.; Cruz-Lopes, LuísaThe chemical structure of lignin from grape stalks, an abundant waste of winemaking, has been studied. The dioxane lignin was isolated from extractive- and protein-free grape stalks (Vitis vinifera L.) by modified acidolytic procedure and submitted to a structural analysis by wet chemistry (nitrobenzene and permanganate oxidation (PO)) and spectroscopic techniques. The results obtained suggest that grape stalk lignin is an HGS type with molar proportions of p-hydroxyphenyl (H), guaiacyl (G) and syringyl (S) units of 3:71:26. Structural analysis by 1H and 13C NMR spectroscopy and PO indicates the predominance of β-O-4′ structures (39% mol) in grape stalk lignin together with moderate amounts of β-5′, β-β, β-1′, 5-5′, and 4-O-5′ structures. NMR studies also revealed that grape lignin should be structurally associated with tannins. The condensation degree of grape stalks lignin is higher than that of conventional wood lignins and lignins from other agricultural residues.
- Numerical study of the optimal nozzle width and jet orientation in a downward blowing air curtainPublication . C. Goncalves, J.; Costa, José Joaquim Da; Gameiro Lopes, Antonio; Figueiredo, A. RuiThis paper presents a numerical study of the performance of an air curtain device (ACD) installed on top of the access door of a refrigerated room, aiming to quantify the influence of some parameters (nozzle width, initial orientation and discharge velocity of the jet) towards the maximization of the sealing effect. For this purpose, a numerical model was developed to simulate the turbulent non-isothermal 3D airflow generated by the ACD jet, focusing on the period after the door is opened. The situation when the ACD is switched off is taken as the reference for the performance evaluation. The results allow identifying an optimum jet nozzle width corresponding to maximum sealing efficiency and lower jet airflow rate (lower energy consumption in the air curtain operation). For the present conditions (ACD installed outside the refrigerated room), the sealing efficiency is highest with the ACD oriented vertically and is practically unaffected if the jet discharge is directed towards the warmer space. On the contrary, a jet discharged towards the cooler space is very detrimental to the ACD sealing effect
- Densification and heat treatment of maritime pine woodPublication . Esteves, Bruno; Ribeiro, Fábio; Cruz-Lopes, Luísa; Ferreira, José; Domingos, Idalina; Duarte, Marta; Duarte, Sónia; Nunes, LinaPine (Pinus pinaster Ait.) wood samples were subjected to a combined treatment by densification and heat treatment. Samples were densified before and after heat treatment. The heat treatment was made inside an oven at 190ºC during 2 to 6 h and wood densification was made in a hot press at around 48 bar pressure and temperatures between 160ºC and 200ºC for 30 min. Compression-set, compression-set recovery after three cycles of water soaking followed by oven drying, density, hardness, bending strength and stiffness and durability against subterranean termites were determined after the treatment. Results show that densification increases density, hardness, bending strength, stiffness and durability against termites. Heat treatment applied after the densification is more effective in reducing compression-set recovery than if applied before.
- Motivations for Food Choices Questionnaire: EATMOTPublication . Guiné, RaquelThis questionnaire aims to collect data to conduct a research on the factors that influence food choice in different countries, integrated in an international project lead by CI&DETS Research Centre of the Polytechnic Institute of Viseu, Portugal (PROJ/CI&DETS/2016/0008: EATMOT). The participation is voluntary and all information collected is strictly confidential. Thank you in advance for your cooperation, without which it would not be possible to realize this project. Remember that there are no good or bad answers, do not hesitate to respond.
- The contribution of a portion of meat, fish and eggs for climate changePublication . Ferreira, Vicente; Domingos, Idalina; Esteves, Bruno; Cruz-Lopes, LuísaIntrodução: A mudança nos padrões alimentares dos cidadãos implicará uma pegada ambiental maior em termos de emissões de gases de efeito estufa e uso de recursos naturais. Por exemplo, dietas ricas em leite e carne, especialmente de ruminantes, estão associadas ao aumento das emissões de metano da fermentação entérica, do dióxido de carbono da deflorestação para dar origem ao pasto e do óxido nitroso da produção de ração. Objetivos: Para um consumo mais sustentável, o objetivo deste estudo foi quantificar e comparar a contribuição para as alterações climáticas de uma porção do que se come em geral, proveniente da Roda dos Alimentos, relacionados com carnes, aves, peixes e ovos, para alcançar uma dieta equilibrada e saudável. Métodos: A Avaliação do Ciclo de Vida, baseada nas normas ISO 14040/44 (2006), foi a metodologia utilizada. A análise de inventário e, posteriormente a análise de impacte foram realizadas utilizando o software SimaPro 8.5. O método escolhido para a avaliação de impacte ambiental foi o IPCC 2013 GWP 100a. Resultados: Os resultados mostram que uma porção de cavala (peixe) apresenta a pegada ecológica inferior seguida da porção de bacalhau, frango, lombo de porco, ovos, lagosta e bife de vaca, respetivamente. Conclusões: A principal conclusão deste estudo é que a avaliação do impacte de ciclo de vida usando o método IPCC 2013 GWP 100a, pode ajudar as pessoas a escolherem os melhores alimentos para uma refeição mais amiga do ambiente, ajudando a mitigar as alterações climáticas.
- Social Justice: Disparities in Average Earnings across Portuguese MunicipalitiesPublication . Martinho, VítorAn ever-ongoing discussion these days involves the disparities in monthly earnings across di erent genders, geographical locations, levels of education, economic sectors, and skills and careers, with various economic and social consequences. In fact, in a framework such as that in which we live in nowadays (with pertinent concerns about economic and social convergences across several indicators), investigating these disparities would be interesting in order to complement the basis that is considered for the design of social policies. There are few studies considering the approaches here developed for this topic. The objective of this study is to analyse the disparities in the average monthly earnings received by employees across Portuguese mainland municipalities over the period 2004–2012, considering as additional analysis criteria geographical location, gender, levels of qualification, levels of education, economic sectors, professional activities, and further qualifications. For this both a cluster and factor analysis were considered to better identify municipalities with similar characteristics and correlations among variables. The results show that the disparities in the monthly average earnings between the Portuguese municipalities are related to three indexes associated with gender, qualifications, and chosen professions. The findings presented are specific to the Portuguese framework; however, the approaches developed in this study may be applied in other contexts to explore the dynamics related with the topic of social justice.
- Bridges between family farming and organic farming: a study case of the Iberian PeninsulaPublication . Guiné, Raquel; Gaião, Davide; Costa, Daniela; Correia, Paula; Guerra, Luis T.; Esteves Correia, Helena; Costa, Cristina Amaro DaThe aim of this work was to identify procedures adopted by family farms in the centre and north of Portu- gal and Galicia (Spain), and to verify whether they resem- ble those used in organic farming. A checklist was pre- pared in Portuguese and Spanish and applied personally to managers of family farms. The participation was volun- tary and 125 valid responses were collected. The results show that farmers included in the study owned small family farms where labour is mainly per- formed by the family, and tended to adopt, in general, good agricultural practices, many of which are common to organic farming, such as crop rotation, avoidance of GMO or avoidance of phytoregulators. However, they failed to adopt some important practices, including the use of seeds inoculated with mycorrhizae, composting, biological and biotechnical control or avoidance of chemical control for plant protection. It was further concluded that gender and age of the farmers did not significantly influence the type of agricultural practices, contrarily to the level of educa- tion and region, which were significantly associated with many of the cultural interventions investigated.
- Artocarpus heterophyllus (Jackfruit): Composition, nutrition Value and ProductsPublication . Guiné, Raquel; Florença, Sofia De Guiné EJackfruit is the largest edible fruit in the world, being cultivated in tropical and sub-tropical regions around the world. This gigantic fruit can be up to 90 cm in length by 30 cm in wide and weight up to 50 kilograms. It is a fruit rich in fibres, proteins, minerals like Calcium, Phosphorus and Iron and Vitamins of Complex B, mainly Vitamin B2 (Riboflavin) and Vitamin B5 (Niacin). Some medicinal properties are attributed to jackfruit, making it a useful tool used in traditional medicine in many parts of the world, such as antiasthmatic, antidiarrheal, anticough healing or diuretics. This chapter compiles some general information about jackfruit as well as its composition and bioactive properties with impact on human health.