Land suitability analysis for emerging fruit crops in central Portugal using GIS

Fruit production is an important component of agricultural production in Portugal, and it has a positive impact on the economy, especially in rural areas. In recent years, there has been increased investment in so-called ‘emerging crops’. It is agreed that using the crops that are best suited to the soil and climate conditions as well as the socio-economic environment promotes sustainable use in rural areas. The objective of this study is to determine the suitability of different emerging fruit crops for cultivation in the Beira Baixa region based on analysis of soil and climate factors. The pistachio tree (Pistacia vera L.), strawberry tree (Arbutus unedo L.), almond tree (Prunus dulcis (Mill.) DA Webb) and walnut tree (Juglans regia L.) were checked against the biophysical criteria for cultivation. The results were processed using a geographic information system. Analysis was performed using the analytical hierarchy process (AHP). Thus, after dividing the problem into hierarchical levels of decision-making, a pairwise comparison of criteria was performed to evaluate the weights of these criteria based on a scale of importance. Then, the consistency of these operations was validated. The AHP was adequate for evaluation of fruit tree species’ suitability since it enabled integration of several criteria, decision-making and problem resolution. It is essential to be aware of the suitability and resilience of new crops in order to meet the need to adapt to climate change.info:eu-repo/semantics/publishedVersio

Determinação da aptidão para desportos de natureza em áreas classificadas com recurso à análise multicritério. A Orientação no Parque Natural do Tejo Internacional.

A crescente procura de territórios rurais para fins turístico-recreativos, com especial incidência nas áreas de valor paisagístico mais elevado, requer a necessidade de compatibilizar a fruição dessas áreas com a preservação e conservação dos valores naturais. Surge, assim, a necessidade de desenvolver uma metodologia de gestão do território apoiada em ferramentas de análise espacial multicritério. Para a determinação das áreas com potencial para a prática das atividades de recreio ativo, recorreu-se à pesquisa de informação, biofísica e socioeconómica, que permitiu a caracterização do território e da sua utilização por parte dos diferentes stakeholders. Por outro lado, foi analisada informação sobre as especificidades das diferentes modalidades de recreio ativo com o objetivo de identificar as condicionantes e potencialidades para a sua prática. A identificação das áreas com aptidão para o recreio, bem como das condicionantes, foi efetuada com base na integração de um conjunto de fatores com recurso ao programa ArcGIS. Os fatores foram classificados em três níveis de aptidão, calculados mediante a aplicação de um método de análise espacial multicritério - o Processo Analítico Hierárquico (AHP). Como resultado obteve-se um modelo de utilização turístico-recreativo do território em estudo numa perspetiva de apoio à sua gestão sustentável.info:eu-repo/semantics/publishedVersio

Weathering influence on physical properties of the Guarda granite, Portugal

The research developed aimed to quantify and understand the evolution of the physical properties of the Guarda granite, Portugal, related with weathering. Samples were collected in selected outcrops representative of the different weathering grades, and when necessary were prepared in the laboratory to be tested with nondestructive techniques. The grades of weathering were defined considering the macro and microscopic observations of the samples combined with the properties measured. It was found that porosity and water absorption tend to increase with increasing weathering, while a reduction in ultrasound velocity occurs. Moreover, it was found that the density of the rock showed no major changes during the weathering sequence, not allowing an easy differentiation of the weathering grades. This is due to the type of weathering imposed on these granites that are essentially of physical nature, without significant variations in the density of the rock. The analysis of the type of porosity was very important in understanding the geometric characteristics of the pore space. Being the granite a material of low porosity, small variations of the property lead to large variations in the behavior of the material. As the increase of porosity in granites indicates major changes, it can be used for a first assessment of rock characteristics. Good correlations were obtained between ultrasound velocity and other parameters like: dry density, porosity, water absorption by capillarity and permeability to oxygen. It was concluded that the texture and the average grain size are important factors to consider in the water absorption by capillary. The relations obtained allow a fast characterization of this granite along its weathering profile

Avaliação dos impactes ambientais de sistemas de produção agrícola alternativos no Baixo Mondego

O objectivo principal deste trabalho centra-se em avaliar os impactes ambientais de dois sistemas de produção agrícola na cultura do milho – Sementeira Directa (SD) e Modo de Produção Biológico (MPB) - na região do Baixo Mondego, Portugal. Durante o estudo, um programa de computador AMBITEC-AGRO - sistema da avaliação do impacto ambiental da tecnologia agropecuária foi utilizado após a adaptação do mesmo à realidade Portuguesa. Um inquérito foi preparado e apresentado aos produtores que aplicavam a(s) tecnologia(s) afim de obter informações sobre o impacte das mesmas quer na parcela ou na região. Os resultados foram recolhidos e inseridos posteriormente no programa afim de proceder à avaliação dos impactes ambientais. Os resultados principais mostram que ambos os sistemas de produção indicam um impacte positivo, com +2.22 para a SD e +2.07 para MPB numa escala de -15 a +15. O software utilizado para avaliação do impacte é de fácil aplicação e pode ser extremamente útil na eco-certificação futura das explorações agrícolas, fornecendo uma ferramenta para avaliar a sua sustentabilidade

Turbulence modelling of multiphase flow in high-pressure trickle-bed reactors

http://www.sciencedirect.com/science/article/B6TFK-4VB01VS-7/2/7dcce0ca6c1ed57a847371407b038f1

Catalytic ozonation of phenolic acids over a Mn-Ce-O catalyst

Catalytic ozonation of a simulated phenolic wastewater composed by six acids: syringic, vanillic, 3,4,5-trimethoxybenzoic, veratric, protocatechuic and 4-hydroxybenzoic normally present in olive mill wastewaters was studied over a Mn-Ce-O laboratorial catalyst under different operating conditions. A high improvement in total organic carbon (TOC) degradation was observed even when low catalyst concentrations were used when compared with single ozonation. The influence of the medium pH in the performance of both single and catalytic ozonation was assessed in a wide range of pH values. An inhibitory effect in TOC removal was observed in the catalytic process performance at high pH values. The use of radical scavengers proved that this catalytic system does not follow a free radical pathway. No differences were observed between fresh and used catalyst structure and morphology by SEM and XRD. Nevertheless, a decrease on BET surface area was detected. Leaching of Mn as well as carbon adsorption due to organic intermediates deposition at the catalyst surface was analyzed for the recovered catalyst at the end of the experiments. The role of the catalyst in the catalytic ozonation pathway was discussed being concluded that the main mechanism should be developed through surface reactions involving both pollutants and ozone adsorption. A series of feed-batch trials was performed to test Mn-Ce-O activity along the time. A slight decrease on TOC removal was observed from the first to the second use, remaining the catalyst performance constant after the third ru

Trickle-bed CFD studies in the catalytic wet oxidation of phenolic acids

An Euler-Euler computational fluid model was developed successfully for the hydrodynamic prediction of a trickle-bed reactor (TBR) designed for advanced wastewater treatment facilities. Catalytic wet air oxidation of phenolic acids was simulated in a TBR by means of computational fluid dynamic (CFD) in the temperature range and pressures . The hydrodynamic model validation was accomplished through the comparison of simulated pressure drop and liquid holdup with experimental data from the literature. In a broad range of gas and liquid flows studied (G=0.10-0.70 and ) at different operation conditions, CFD demonstrated the considerable effect of operating pressure in pressure drop, whereas a minor influence was detected for the liquid holdup. CFD runs were then performed for the catalytic wet air oxidation of aqueous phenolic acids solution. The reactor behaviour was analysed by means of total organic carbon profiles which reflected the influence of temperature, pressure, gas-liquid flows and initial pollutant concentration.http://www.sciencedirect.com/science/article/B6TFK-4PPMXS0-1/1/2dabed7df5e98dfd85f3fef6ef64782

57Fe Mössbauer Studies in Mo–Fe Supported Catalysts

Abstract Industrially, the Mo–Fe catalysts used in the selective oxidation of methanol to formaldehyde can rapidly deactivate. The use of support materials may reduce the high temperatures in the catalytic bed and/or increase thermal and mechanical resistance. However, during the preparation of these catalysts, or even during reaction conditions, the active species may react with the support material losing their catalytic activity. In this work silica, silicium carbide and titania were studied as supported catalysts by Mssbauer spectroscopy which proved to be a useful technique in the choice of supported materials

Caracterização da prática das Ciências no Ensino Básico – 1º Ciclo

p. 85-91Com as Reformas Curriculares do 1º Ciclo do Ensino Básico, o Ensino Experimental das Ciências tem vindo a ser implementado como metodologia de desenvolvimento da área do Estudo do Meio e, indirectamente, de todas as outras áreas, favorecendo no aluno a construção do seu próprio conhecimento.Neste contexto, o professor deverá criar ambientes propícios à aprendizagem e desenvolver, com as suas práticas, as competências necessárias nos alunos. Um dos factores que pode condicionar a prática pedagógica é a formação do professor, quer ao nível da sua formação inicial, quer no que se refere à procura de formação ao longo da vida. O inquérito por questionário foi o instrumento escolhido para avaliar a postura de 24 professores do 1º Ciclo perante o ensino experimental das Ciências. Comparámos as atitudes demonstradas por um grupo de professores formados pelas Escolas do Magistério Primário com as de um outro formado por Escolas Superiores de Educação. Relativamente ao gosto pelos temas das Ciências, à realização de experiências com os alunos, privilegiando o trabalho individual e de grupo e à valorização da metodologia por descoberta, estes factores não constituíram elementos diferenciadores entre os grupos. Vinte e três dos 24 inquiridos já tinham realizado experiências mas encontramos discrepâncias nas respostas em ambos os grupos, uma vez que os temas mais abordados experimentalmente não eram aqueles em que se sentiam mais seguros, nem tão pouco indicados como exemplo de experiências realizadas com êxito. Os professores formados no Magistério (54%) assumiram sentir necessidade de formação nesta área, principalmente sob uma abordagem experimental, mas complementada em 80% dos casos com informação científica, enquanto que os professores formados nas ESEs (43%) privilegiaram a formação experimental. O nosso estudo aponta no sentido em que a formação inicial do professor do 1º Ciclo não parece ser um factor limitativo da realização de uma boa prática pedagógica na área das Ciências, sendo influenciado positivamente pela procura de formação ao longo da vida