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Mestrado em Engenharia Química No contexto de elementos construtivos, como paredes e pavimentos de edifícios, um dos grandes problemas é o transporte de humidade e a deposição de sais solúveis, pelo que é necessário propor-se soluções que evitem e/ou corrijam estes obstáculos, preservando os materiais construtivos, assim como o conforto e bem-estar dos seres humanos. Nesta dissertação é proposta uma solução que implica utilizar argila expandida em pavimentos e rebocos de saneamento em paredes. Esta solução carecia de avaliação experimental ao nível de eficiência de corte capilar como estratégia principal para controlar o transporte e deposição de sais nos elementos selecionados. O contributo deste trabalho prende-se com a avaliação de argila expandida (Leca) e respetiva avaliação após tratamento hidrófugo e também de duas argamassas de saneamento (APT e APC). A avaliação consiste no estudo do movimento de água por capilaridade e fase de vapor ao longo das camadas testadas, medindo-se curvas de humidificação e secagem dos vários materiais. Dos dados experimentais obtiveram-se os coeficientes de capilaridade e os fluxos de água para tempos característicos. Regra geral, mostrou-se que a aplicação de uma camada de Leca hidrofugada combinada com Leca não hidrofugada reduz com sucesso o fluxo de água absorvida. A posição da camada hidrofugada na estrutura construtiva (piso térreo) é também fundamental, tendo-se mostrado que deve ser a que contacta diretamente com a fonte de água (face inferior de um pavimento). Relativamente ao transporte de sais, estudou-se a ação de sais de cloretos e sulfatos sobre as argamassas APC e APT, tendo-se observado que, após 47 ciclos de cloretos e 55 de sulfatos, os provetes de APC não sofreram alterações visíveis ao invés dos de APT, cujas arestas e vértices ficaram arredondados e desgastados. A Leca, muito embora tenha potencial para reter água, não se mostrou capaz de reter sais de ambos os aniões, tendo-se, por este motivo, parado este ensaio após 24 ciclos de sais de sulfatos e 20 de sais de cloretos. Face aos resultados obtidos, é possível admitir que um leito de pavimento com Leca, associado a uma parede com reboco de saneamento (APT e APC), apresenta um transporte de água adequado, sendo a Leca, especialmente se for hidrofugada, um tampão ao excesso de água na zona de paredes que causam a sua potencial degradação, especialmente quando existem sais. In the context of constructive elements, as walls and pavements from buildings, one of the biggest problems is the transport of humidity and the deposition of soluble salts, whereby it is necessary to propose solutions that avoid and/or correct these obstacles, preserving the constructive materials, as well as the comfort and well-being of humans. In this dissertation it is proposed a solution involving the utilization of expanded clay in pavements and salt-accumulation renders in walls. This solution lacked of experimental evaluation at the level of the efficiency of capillary cut as first strategy to control the transport and deposition of salts in the selected elements. The contribution of this work concerns the evaluation of the expanded clay (Leca) and respective evaluation after treatment with water-repellent and also of two renders (APT e APC). The evaluation consists in the study of the water movement by capillarity and vapor phase thought the tested layers, measuring curves of humidification and drying of the various materials. From the experimental data were obtained the capillarity coefficients and the water flows for characteristic times. General rule, were shown that the application of a waterproofed layer of Leca combined with one not waterproofed decreases with success the absorbed water flow. The position of the waterproofed layer in the constructive structure (ground floor) is also fundamental, having been shown that must be the one that contacts directly with the water source (the underside of a pavement). Relatively to the salt transport, it has been studied the action of chlorides and sulfates salts over the renders APC and APT, having been observed that, after 47 cycles of chlorides and 55 of sulfates, the samples of APC didn’t suffer visible changes, instead of the ones of APT, whose edges and vertices stayed round and worned. Leca, although the great potential to hold water, wasn’t able to hold salts from both anions, so, for this reason, this test have been stopped for this material after 24 cycles of sulfate salts and 20 of chloride salts. According to the obtained results, it is possible to admit that a deck bed with Leca, associated to a wall with salt-accumulating renders (APT e APC), presents an adequate transport of water, being Leca, especially if it is waterproofed, a tampon to excess of water that causes the potential degradation in the zone of walls, especially when there are salts.

Doutoramento em Engenharia Florestal - Instituto Superior de Agronomia - UL Vegetation fires are an important component of the earth’s system land processes and have a significant impact on the vegetation and CO2 dynamics. The global fire patterns are not thoroughly explored and the drivers of fire regimes in global scale are interconnected. However, several modelling assumptions are contradicted by exploring those relationships partially. At global scale, fire extent is fuel limited, with climatic variables showing both positive and negative influence on fuel moisture conditions, and humans showing a negative net effect. When isolating the influence of population density and assuming spatial nonstationarity, the human impact is very detailed and reflects the main land use activities with emphasis on cropland and rangeland management at continental scale. The footprint of fire into the Earth system can be measured in terms of radiative forcing from pre and post-fire albedo changes, with the forest biomes driving the extremes on annual basis. Additionally this thesis explores the patterns and the trends of contemporary fire activity. Contrary to previous studies, the results show non-monotonic patterns at grid cell level. The findings of this thesis give a better insight into the spatial variability and the controls of fire at global scale using satellite derived datasets with a focus to the anthropogenic land use activities

Mestrado Mediterranean Forestry and Natural Resources Management - Instituto Superior de Agronomia - UL In Portugal, wildfires represent a major concern that yearly produces numerous economic and environmental losses. Currently, there is a continuous increase of biomass accumulation which increases wildfire risk into Mediterranean protected areas due to lack of management. An example is the protected area of Serra da Malcata, where prescribed burning has been implemented. However, fuel treatments implementation within preserved areas remains quasi forbidden in the major cases. The main objective is to develop and asses a novel approach to reduce fire exposure and simultaneously promote conservation habitat within Natura 2000 Habitats of Reserva Natural da Serra Malcata. For this aim, fire exposure assessment of three different fuel management scenarios: current situation, planned treatments and low intense treatments within Habitat Natura 2000 promoting conservation goals, were done by using burn probability modelling under extreme conditions for 24h burn period. Results showed similar performance of conservation enhancement scenario if compare with planned treatment scenario. Nevertheless, biggest fire exposure reductions were observed within Natura 2000 network. Limitations and assumptions derived from input parameters, model validation or fire simulator could affect fire exposure results. However, results open the debate to include fuel treatments within protected areas for achieving medium- and long-term fire risk reduction

Doutoramento em Engenharia Agronómica - Instituto Superior de Agronomia - UL The olive tree (Olea europaea L.) has been shaping and characterizing landscape and culture in the Mediterranean basin. This tree is attacked by pest that can cause significant losses. This thesis was focused on the conservation biological control of one of its most damaging pests: the olive moth, Prays oleae (Bernard). Naturally, a large number of parasitoid and predator species are associated to this pest, and in order to satisfy their needs they make use of ecological infrastructures occurring in the olive grove agroecosystem. However, how these ecological infrastructures can be used to enhance the olive moth conservation biological control needs to be disentangled. For that, two approaches were followed. First, the influence of ecological infrastructures on P. oleae and its natural enemies was analyzed through field surveys. Then, different food resources were evaluated as potential foods for P. oleae and its natural enemies, i.e., the parasitoid Elasmus flabellatus (Fonscolombe) and the predator Chrysoperla carnea s. l. (Stephens). In the first approach, P. oleae was found to disperse throughout non-crop patches, although the implications for the pest population are unknown. The heterogeneous landscapes composed by herbaceous and woody vegetation around the olive groves were exploited by syrphids as food sources. Finally, ground covers within the olive groves favored the parasitoid Ageniaspis fuscicollis (Dalman) while the herbicide application diminished it. In the second approach, insects’ honeydews [Saissetia oleae (Olivier) and Euphyllura olivina (Costa)] and the flowers of Malva sylvestris L. favored the survival and/ or reproduction of P. oleae, C. carnea and E. flabellatus. Several plant species such as Daucus carota L., Veronica persica Poir, and Lamium purpureum L. showed to be potential food resources for the studied natural enemies. From the results obtained in this research various applications for managing the olive grove agroecosystem are proposed

Dissertação de Mestrado em Gestão Artística e Cultural apresentada na Escola Superior de Educação do Instituto Politécnico de Viana do Castelo Esta dissertação tem como eixo central a necessidade de se produzir estudos críticos sobre o desenho de projetos culturais. Especificamente, projetos culturais que são desenhados em conjunto com instituições de grande relevância no seu local de implementação. Ambiciona-se produzir uma análise multidimensional e, em simultâneo, fazer a sua integração no próprio desenho e nos objetivos da intervenção cultural em construção. Também a necessidade de estudar e de refletir sobre o desenho de uma intervenção que não ocorre num contexto neutro, mas que tem lugar num local específico. Lugar deve aqui ser entendido na sua definição mais abrangente, que ultrapassa os elementos físicos e inclui todos os aspetos sociais na sua articulação com a história e a memória de um determinado local. Os resultados obtidos permitem reforçar a ideia de que não existiam estudos metodológicos aplicados no desenho de projetos culturais. Apesar da maioria das ideias culturais que circulam, revelarem o talento e a capacidade criativa de quem as criou, como no caso das várias instituições da cidade de Viana do Castelo por nós entrevistadas, acabam por transmitir, imensas vezes, a debilidade que decorre da falta de uma metodologia adequada a esse mesmo desenho. Face à crescente abertura e ao aumento da exigência cultural que se está a materializar atualmente, os profissionais da Gestão Cultural têm cada vez mais necessidade de dotar-se de instrumentos de trabalho adequados para a concetualização, realização e produção de réditos cada vez mais diversificados e sofisticados, na medida em que vão produzir cultura e desenvolver a sociedade. Seria um erro pensar que para obter um bom desenho de projeto basta que este esteja tecnicamente bem formulado. Constatamos neste estudo que o melhor dos projetos é aquele que segue uma metodologia sólida e autocrítica, fundamentando bem as suas finalidade e o seu contexto. This thesis relies on the necessity to produce critical studies about the design of cultural projects. In particular, cultural projects which are designed also by the greatest institutions of its implementation area. We aim to analyse the different shapes and, at the same time, to integrate it in the design itself and in the objectives of the cultural intervention that is being built. We also rely on the need to study and reflect about the design of an intervention which doesn’t take place in a neutral context, but that occurs in a particular place. Place, refers to a wider definition which surpasses all the physical elements and includes all the social aspects in its articulation with the memory and history of a certain place. The results allow us to reinforce the idea that there weren’t methodological studies properly used in the design of cultural projects adopting a strategy which we will call place-specific1. Although most cultural ideas reveal the talent and the creative capacity of its author, as in the case of the majority of the interviewed institutions in Viana do Castelo, they end up by transmitting a weakness which derives from the lack of an appropriate methodology of its design. Due to the increase and the dawn of the cultural demanding that we are facing nowadays, the professionals of Cultural Management have to acquire appropriate tools for the conceptualization, creation and production of more and more sophisticated and diversified revenues which will produce culture and develop society. It would be an inaccuracy to believe that to obtain a superior project design it’s enough that it is technically well conceived. We observed, through this study, that the best project is the one that adopts its own methodology, setting its aims and context in a very accurate way.

Dissertação de Mestrado em Direito, Especialidade em Ciências Juridico-Forenses, apresentada à Faculdade de Direito da Universidade de Coimbra

The thesis is aimed at the investigation of niche applications of solid-state lighting with controllable colour-rendition, spatial, photochemical, and photobiological properties. In order to employ the controllability of light emitting diode (LED) based lighting technology, the research on such niche applications as artwork illumination and street lighting are focussed. The smart colour rendition engine (CRE), which allows for continuously tuning metameric spectra with different colour rendition properties, is introduced. The results on the subjective validation of the statistical colour rendition metric using the CRE are presented. The main requirements for artwork illumination are overviewed and the application of the intelligently controlled CRE in artwork illumination is investigated in two aspects: a) the establishment of subjective needs in colour quality of illumination as a function of the contents of artworks and the observers’ cultural background and b) the effect of the control of photochemical damage irradiance on the visual impression from artworks, while adjusting the chromaticity and colour rendition properties of the illuminant. The results on the optimization of the luminance distribution within an intelligent lighting installation for pedestrian areas using the identification of subjective impressions are presented. The low-circadian action LED source for outdoor lighting is introduced and the results on the assessment of photometric, colorimetric... [to full text] Ši disertacija yra skirta ištirti kietakūnio apšvietimo su valdomomis spalvų perteikimo, erdvinėmis, fotocheminėmis ir fotobiologinėmis savybėmis galimus nišinius taikymus. Kaip nišinių taikymų pavyzdžiai, kuriuose ryškiausiai atsiskleidžia valdomo apšvietimo privalumai, buvo pasirinkti dailės kūrinių apšvietimas ir gatvių apšvietimas. Šiame darbe pristatytas išmanusis spalvų perteikimo variklis (SPV), leidžiantis tolydžiai keisti metamerinius spektrinės galios skirstinius, pasižyminčius skirtingomis spalvų perteikimo savybėmis. Naudojant SPV validuotas statistinis apšvietimo spalvinės kokybės vertinimo metodas. Apžvelgti dailės kūrinių apšvietimo reikalavimai bei pristatomi SPV pritaikymo dailės kūrinių apšvietimui pagal du kriterijus tyrimai: a) įvertinant apšvietimo spalvinei kokybei teikiamos subjektyvios pirmenybės priklausomybę nuo dailės kūrinio turinio ir žiūrovų kultūrinės kilmės; b) parodant regimosios išraiškos pokytį, atsirandantį dėl apšvietos lygio kitimo, kuomet fiksuojama apšvietimo fotocheminė įtaka apšviečiantiems paviršiams, kintant kokybiniams apšvietimo parametrams. Pristatomi apšvietimo skirstinio pėsčiųjų zonai optimizavimo rezultatai, gauti įvertinus subjektyvius poreikius. Pasiūlytas žemo cirkadinio poveikio kietakūnis šviesos šaltinis, skirtas lauko apšvietimui. Įvertintos tokio šaltinio fotometrinės, kolorimetrinės, spalvų perteikimo, fotobiologinės ir šviesinės taršos savybės bei atlikti tyrimai, įvertinantys psichofizines savybes.

Ši disertacija yra skirta ištirti kietakūnio apšvietimo su valdomomis spalvų perteikimo, erdvinėmis, fotocheminėmis ir fotobiologinėmis savybėmis galimus nišinius taikymus. Kaip nišinių taikymų pavyzdžiai, kuriuose ryškiausiai atsiskleidžia valdomo apšvietimo privalumai, buvo pasirinkti dailės kūrinių apšvietimas ir gatvių apšvietimas. Šiame darbe pristatytas išmanusis spalvų perteikimo variklis (SPV), leidžiantis tolydžiai keisti metamerinius spektrinės galios skirstinius, pasižyminčius skirtingomis spalvų perteikimo savybėmis. Naudojant SPV validuotas statistinis apšvietimo spalvinės kokybės vertinimo metodas. Apžvelgti dailės kūrinių apšvietimo reikalavimai bei pristatomi SPV pritaikymo dailės kūrinių apšvietimui pagal du kriterijus tyrimai: a) įvertinant apšvietimo spalvinei kokybei teikiamos subjektyvios pirmenybės priklausomybę nuo dailės kūrinio turinio ir žiūrovų kultūrinės kilmės; b) parodant regimosios išraiškos pokytį, atsirandantį dėl apšvietos lygio kitimo, kuomet fiksuojama apšvietimo fotocheminė įtaka apšviečiantiems paviršiams, kintant kokybiniams apšvietimo parametrams. Pristatomi apšvietimo skirstinio pėsčiųjų zonai optimizavimo rezultatai, gauti įvertinus subjektyvius poreikius. Pasiūlytas žemo cirkadinio poveikio kietakūnis šviesos šaltinis, skirtas lauko apšvietimui. Įvertintos tokio šaltinio fotometrinės, kolorimetrinės, spalvų perteikimo, fotobiologinės ir šviesinės taršos savybės bei atlikti tyrimai, įvertinantys psichofizines savybes. The thesis is aimed at the investigation of niche applications of solid-state lighting with controllable colour-rendition, spatial, photochemical, and photobiological properties. In order to employ the controllability of light emitting diode (LED) based lighting technology, the research on such niche applications as artwork illumination and street lighting are focussed. The smart colour rendition engine (CRE), which allows for continuously tuning metameric spectra with different colour rendition properties, is introduced. The results on the subjective validation of the statistical colour rendition metric using the CRE are presented. The main requirements for artwork illumination are overviewed and the application of the intelligently controlled CRE in artwork illumination is investigated in two aspects: a) the establishment of subjective needs in colour quality of illumination as a function of the contents of artworks and the observers’ cultural background and b) the effect of the control of photochemical damage irradiance on the visual impression from artworks, while adjusting the chromaticity and colour rendition properties of the illuminant. The results on the optimization of the luminance distribution within an intelligent lighting installation for pedestrian areas using the identification of subjective impressions are presented. The low-circadian action LED source for outdoor lighting is introduced and the results on the assessment of photometric, colorimetric... [to full text]

Mestrado em Engenharia Química As lâminas cerâmicas são um novo material cerâmico presente no mercado de espessura reduzida e elevadas dimensões. São por isso materiais mais frágeis que necessitam do reforço do seu tardoz através da colagem de fibra de vidro. Porém este reforço tende a limitar a adesão eficaz deste tipo de cerâmico com os elementos de colagem devido a alguma incompatibilidade química entre os materiais envolvidos. Este trabalho pretende avaliar a adesão (comumente referida como aderência no meio industrial) de lâminas cerâmicas em argamassas-cola. Para tal, os elementos constituintes do tardoz da lâmina cerâmica foram estudados recorrendo a diversas técnicas. Inicialmente foi estudada a solubilidade dos materiais do tardoz em diversos solventes, embora não se tenha conseguido a sua dissolução em nenhum dos solventes testados. Por esse motivo o tardoz completo foi estudado por Espetroscopia no Infravermelho com Transformada de Fourier (FTIR), Ressonância Magnética Nuclear (13C-RMN) e análises termogravimétricas (TGA) entre os 20ºC e os 900ºC. Os resultados obtidos indicam que as colas do tardoz são à base de poliuretano de poliéster. Posteriormente, avaliou-se a aderência, segundo a norma EN 12004, das lâminas cerâmicas em três argamassas-cola distintas: uma de base cimentícia, uma de base epóxi e uma de base poliuretano. Estes estudos permitiram verificar que o substrato de base epóxi é aquele que garante melhor aderência, obtendo-se valores de tensão de aderência de 4 N/mm2 e roturas de natureza coesiva no substrato. Foi também avaliado o uso de um primário de aderência e caracterizada a resina do mesmo, o que permitiu verificar a sua importância relativamente à adesão entre a argamassa cimentícia e o tardoz. Após os ensaios de aderência as amostras mais representativas foram ainda analisadas através de microscopia eletrónica de varrimento (SEM). As imagens revelaram que os vários substratos não aderiram de forma eficaz à fibra de vidro, no entanto a importância da utilização do primário foi confirmada. Thin tiles are a new ceramic material present in the market with reduced thickness and higher dimensions. They are therefore more fragile materials thus they require reinforcing of its backside by gluing fiberglass. However, this reinforcement has been hampered by the chemical incompatibility between the materials resulting in poor adhesion between the thin tiles and adhesive mortars. This work intends to evaluate the adhesion of thin tiles in adhesive mortars normally referred to as adherence in industry. To this end, the constituent elements of the backside of the thin tiles were studied using various techniques. Initially, the solubility of these materials in various solvents was studied yet dissolution did not occur in any of tested solvents. For this reason the full backside was studied by Infrared Spectroscopy Fourier Transform (FTIR), Solid State Nuclear Magnetic Resonance (13C-NMR) and thermogravimetric analysis (TGA) between 20 ºC and 900 ºC. The results indicate that the backside glues are a polyurethane-based polyester. Later, the adhesion of thin tiles was also studied, according to norm EN 12004 on three different adhesive mortars: one cement based, one epoxy-based and a polyurethane-based. These studies revealed that the epoxy-based substrate is the one that ensures better adhesion achieving values of adhesion strength 4 N/mm2 and cohesive adhesion in the substrate. The use of an adhesion primer was also assessed and its chemical characterization carried out, which has shown its importance in relation to the adhesion between the cement mortar and the backside of thin tiles. After the pull-off tests the most representative samples were analyzed by scanning electron microscopy (SEM). The images showed that the various substrates did not adhere well to the fiberglass but the importance of the use of primary was confirmed.

Dissertação de Mestrado em Direito, Especialidade em Ciências Juridico-Forenses, apresentada à Faculdade de Direito da Universidade de Coimbra

Dissertação de Mestrado em Direito, Especialidade em Ciências Juridico-Forenses, apresentada à Faculdade de Direito da Universidade de Coimbra

Mestrado em Arquitetura Paisagista - Instituto Superior de Agronomia The Portuguese forest service’s fire management policy has been substantially overhauled in the last few years, and a new emphasis has been put on the wildland-urban interface (WUI). When forest fires break out more frequently next to homes and urban settlements, and become increasingly more dangerous, this constitutes a worrying and important topic, not only in Portugal, but in all Mediterranean countries. The present study consists of mapping, the regulations defined by Decree n. 17/2009, from January 14th, to a map, with detailed representation of secondary networks for fuel-breaks (fuel build-up control) in two contrasting landscapes. The goals of this study were: (i) to transpose the legislation into cartography; (ii) to estimate costs of the creation of the secondary network, based on a very simple assumption of the type of operation to be carried out, (iii) to identify local and regional differences and (iv) to identify local and regional differences and (iv) to compare our mapping with that performed under a Municipal Plan For Forest Protection Against Wildfires. The development of the study took place in two areas, located to the North and Center of Portugal. The results show that the legislation is sufficiently clear to allow for the representation, on a map, of secondary network lanes, in all their representations. They also show that the dimensions of the secondary network, the estimate of costs for the creation of said secondary network and the interventional priority differ, according to the type and landscape

Mestrado em Engenharia Civil A reabilitação de fachadas dos edifícios antigos, anteriores à utilização do betão armado, tem sido alvo de vários estudos em torno de argamassas de substituição compatíveis com os materiais pré-existentes. Grande parte dessas fachadas é revestida por azulejos tradicionais e é extremamente importante a sua preservação e manutenção. No entanto, as argamassas normalmente formuladas para o reassentamento de azulejos, que garantem a compatibilidade entre os diversos materiais, não são classificadas como argamassas-cola por não cumprirem os requisitos normativos da EN 12004. Pretende-se desenvolver uma argamassa-cola, com materiais compatíveis com os sistemas antigos, que cumpra com os requisitos para colas de fixação de cerâmicos exigidos pela EN 12004. Estas exigências nem sempre são fáceis de alcançar ou de compatibilizar. Por forma a atingir o objetivo proposto, inicialmente foram estudadas argamassas com base em ligantes com diferentes graus de compatibilidade: argamassas de cimento, de cal aérea e de cal hidráulica. Os resultados obtidos conduziram ao estudo de diversos materiais pozolânicos, por forma a apurar-se os que podem, potencialmente, ser utilizados em argamassas-cola como substituição, parcial ou quase total, do cimento. As argamassas-cola desenvolvidas, contendo materiais pozolânicos nas suas formulações, foram caracterizadas em estado fresco e em estado endurecido. De entre todas as argamassas em estudo, foram escolhidas aquelas que de acordo com a EN 12004, obtiveram resultados satisfatórios. Estes produtos foram caracterizados, em conjunto com duas argamassas produzidas pela Saint-Gobain Weber, em estado fresco e em estado endurecido. Na caracterização dos produtos endurecidos, foram realizados estudos de compatibilidade entre as argamassas e o cerâmico tradicional utilizado (ensaios de aderência, químicos e físicos) e de compatibilidade entre as argamassas e os suportes antigos (ensaios mecânicos, químicos e físicos). The rehabilitation of facades of the old buildings, prior to the use of reinforced concrete, has been the subject of several studies around of replacement mortars compatible with the pre-existing materials. Most of these facades are covered with traditional tiles and is extremely important their preservation and maintenance. However, the mortars normally formulated for the resettlement of tiles, that ensure the compatibility between the different materials are not classified as adhesive mortars for not complying with the standard requirements of EN 12004. It is intended to develop an adhesive mortar, with compatible materials with the old masonries which comply with the requirements for adhesives of ceramic fixing required by EN 12004. These requirements are not always easy to reach or reconcile. In order to achieve the aim proposed, initially were studied mortars based in binders with different degrees of compatibility: cement mortars, air lime mortars and hydraulic lime mortars. The results obtained have led to the study of several pozzolanic materials, in order to establish those who may potentially be used in adhesive mortars as a replacement, partial or almost total, of the cement. The adhesive mortars developed, containing pozzolanic materials were characterized in fresh and hardened state. Among all the mortars studied, were chosen those that have obtained satisfactory results, according to the EN 12004. These products were characterized, in conjunction with two mortars produced by Saint-Gobain Weber, in fresh and hardened state. In the characterization of hardened products, were performed studies of compatibility between the mortars and the traditional ceramic (tests of adhesion, chemical and physical tests) and studies of compatibility between the mortar and the old masonries (mechanical, chemical and physical tests).

Mestrado em Engenharia Civil O presente trabalho decorre da importância crescente da adoção de um pensamento ecológico no que diz respeito à indústria da construção, sendo um dos setores mais ativos no consumo de matérias-primas de elevadas quantidades de energia, gerando muitos resíduos (construção e demolição). O cimento Portland é um dos materiais mais utilizados na indústria da construção e associado ao seu fabrico estão as elevadas emissões de CO2. Na tentativa de redução dessas emissões tem-se vindo a estudar várias alternativas para a indústria do cimento. Neste estudo foi investigado o uso da adição da escória de alto – forno em argamassas – cola do tipo C1 e C2, em substituição do cimento Portland. Procedeu-se à caracterização química da escória de alto – forno (granulometria, difração de raios X, análises térmicas, distribuição de tamanho da partícula, método de BET e avaliação da reatividade pozolânica) e avaliação/caracterização da substituição parcial de cimento Portland e cimentos – cola adotando a norma EN12004 e respetivos ensaios. Os resultados alcançados permitem concluir que as principais propriedades físicas não são afetadas, para adições até 25% do resíduo, aos cimentos. Por outro lado, substituições superiores implicam trabalhos adicionais de ajustamento de formulações para manter um comportamento das argamassas aceitável ao nível o seu caderno de especificações. This study results from the importance of increasing adoption of ecological thinking with regard to the construction industry. Being one of the most active sectors, which consumes more raw materials and high amounts of energy, creating a lot of wastes (construction and demolition). Portland cement is one of the most widely used materials in the construction industry and their manufacture is associated to elevated CO2 emissions. In the attempt to reduce greenhouse gas emissions has been study several alternatives for the cement industry. It was investigated the addition of blast furnace slag in C1 and C2 kind of mortar to replace Portland cement. It was made the chemical characterization of blast furnace slag (grain size, x-ray, thermal analysis, the particle size distribution, BET method and evaluation of the pozzolanic reactivity) and evaluation /characterization of a partial replacement of Portland cement in cimentitious tile adhesives, adopting EN 12004 standard and related test methods. The results obtained allow to conclude that the main physical properties are not affected, for additions up to 25% of the residue to cement. On the other hand, higher substitutions requires additional work formulations adjustment to maintain an acceptable behavior of the mortar at their specification level.

Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia This thesis aimed to perform a trend analysis of the global distribution of vegetation fires for the period from June 1996 to March 2012. We used the product from the World Fires Atlas (WFA) from the European Space Agency (ESA), obtained with the Along Track Scanning Radiometer (ATSR) sensor onboard the Second European Remote Sensing Satallite (ERS – 2), under which a filtering process was applied, following the same method of Mota et al. (2006). We conducted a comparative analysis between the initial data and the clean data and there was a percentage of false alarmes and fires that were not vegetation fires of 28%. The errors obtained were due primarily to hot surfaces and gas flares. With the data obtained, we conducted a trend analysis by performing the Mann-Kendall test in the program IDRISI Selva. The mapping created by the test, was studied to identity the presence of positive or negative trends. After a close visual study of the mapping and after the analysis of the temporal profiles of places of interest, we concluded that there is no relevant trend present globally, both positive or negative.

At the time of writing of this Thesis more than 900 planets have been announced and about 2700 planets from the Kepler space telescope are waiting to be confirmed. The very precise spectra and light curves obtained in Doppler and transit surveys, allows the in-depth study of the parameters of the host stars, and opens the possibility to investigate the star-plant correlations. Also, determining the stellar parameters with precision is critical for more precise determinations of the planetary parameters, namely, mass, radius, and density.In the case of the FGK dwarfs, the determination of stellar parameters is well established and can be used with confidence to study the star-planet relation as well as to obtain precise planetary parameters. However, this is not the case for M dwarfs, the most common stars in the Galaxy. Compared to their hotter cousins, M dwarfs are smaller, colder, and fainter, and therefore harder to study. The biggest challenge regarding M dwarfs is related to the presence of billions of molecular lines that depress the continuum making a classical spectral analysis almost impossible. Finding new and innovative ways to overcome this obstacle in order to obtain precise stellar parameters is the goal of this Thesis.To achieve this goal I focused my research into two main avenues: photometric and spectroscopic methods. My initial work had the objective of establishing a precise photometric metallicity calibration, but I could not reach this goal, as I did not have enough FGK+M binaries with good photometric data. However, it was possible, with the available data, to compare the already established photometric calibrations and slightly improve the best one, as described in Chapter 3.Then, I focused on spectroscopic approaches with the aim of obtaining precise M dwarf parame- ters. To this end I used HARPS high-resolution spectra and developed a method to measure the spectral lines disregarding the continuum completely. Using this method I established a new visible calibration with a precision of 0.08 dex for [Fe/H] and 80 K for Te f f . This work is detailed in Chapter 4.Finally, I also participated in the refinement of the parameters of the star GJ3470 and its planet, where my expertise in stellar parameters of M dwarfs had an important role. The details regarding this investigation are shown in Chapter 5.; Au moment d'écrire ma Thèse plus de 900 exoplanètes été annoncées et plus de 2700 planètes détectées par le télescope spatial Kepler sont en attente d'être confirmées. La haute précision des spectres et des courbes de lumière obtenue dans les relevés Doppler et transit, permet l'étude détaillée des paramètres des étoiles hôtes, et ouvre la possibilité d'enquêter sur les corrélations étoile planètes. En outre, la détermination des paramètres stellaires avec précision est un besoin critique pour déterminer les paramètres planétaires, à savoir, la masse, le rayon et la densité.Dans le cas des naines FGK, la détermination des paramètres stellaires est bien établie et peut être utilisée avec confiance pour étudier la relation planète-étoile ainsi que pour obtenir les paramètres planétaires avec une grande precision. Cependant, ce n'est pas le cas pour les naines M, les étoiles les plus communes de la Galaxie. Par rapport à leurs cousines plus chaudes, les naines M sont plus petites, plus froides, et plus faiblement lumineuses, et donc plus difficile à étudier. Le plus grand défi qui concerne les naines M est lié à la présence de milliards de lignes moléculaires qui gomme le continuum et rend l'analyse spectrale classique presque impossible. Trouver des fac ̧ons nouvelles et novatrices pour surmonter cet obstacle et obtenir une mesure des paramètres stellaires est l'objectif principal de cette Thèse .Pour l'atteindre, j'ai concentré mes recherches sur deux approches méthodologiques, photométrique et spectroscopiques. Mon premier travail avait pour objectif d'établir l'étalonnage de métallicité pho- tométrique précis. Par manque de binaires FGK+M avec de bonnes données photométriques je ne pouvais pas atteindre cet objectif. Il m'a cependant était possible, avec les données disponibles, de comparer les étalonnages photométriques déjà établies et légèrement améliorer le meilleur d'entre eux, comme décrit au Chapitre 3.Puis, je me suis concentré sur les approches spectroscopiques pour obtenir des paramètres stel- laires plus précis pour les naines M. À cette fin, j'ai utilisé des spectres HARPS de haute résolution et développé une méthode pour mesurer les lignes spectrales sans tenir compte du continuum . En utilisant cette méthode, je créé un nouvel étalonnage visible avec une précision de 0.08 dex pour [Fe/H] et 80 K pourTeff .Ce travail est détaillé dans le Chapitre 4.Finalement , j'ai également participé à l'amélioration des paramètres de l'étoile GJ3470 et de sa planète, où mon expertise dans les paramètres stellaires de naines M avait un rôle important. Les détails concernant cette enquête sont présentés dans le Chapitre 5; No momento em que escrevo esta Tese, o número de planetas anunciados já ultrapassou os 900 e os cerca de 2700 candidatos detectados pelo telescópio espacial Kepler esperam por confirmação. Os espectros e as curvas de luz obtidos nos programas de procura de planetas permitem, também, o estudo em profundidade dos parâmetros das estrelas com planetas e abrem a possibilidade de investigar a relação estrela-planeta. Neste contexto, a determinação com precisão dos parâmetros estelares é crítica na determinação precisa dos parâmetros planetários, nomeadamente, a massa, o raio e a densidade.No caso das anãs FGK, os métodos de determinação dos parâmetros estelares estão bem estabelecidos e podem ser usados com confiança no estudo da relação estrela-planeta, assim como na obtenção de parâmetros planetários precisos. No entanto, não é esse o caso para as anãs M, as estrelas mais comuns da nossa Galáxia. Ao contrário das suas primas, as estrelas M são mais pequenas, frias e ténues e, assim sendo, mais difíceis de estudar. O grande entrave no estudo das estrelas M está relacionado com a presença de biliões de linhas moleculares que deprimem o contínuo espectral, fazendo com que uma análise espectral clássica se torne quase impossível. A procura de métodos inovadores que possibilitem ultrapassar este obstáculo, tendo em vista a obtenção de parâmetros precisos, é o objectivo desta Tese.Tendo em conta esse objetivo, foquei os meus esforços em duas linhas principais de pesquisa, baseadas em métodos fotométricos e métodos espectroscópicos. O meu trabalho inicial tinha como objetivo o estabelecimento de uma calibração fotométrica para a metalicidade, mas não me foi possível atingir esse objetivo, pois não tinha sistemas binários FGK+M suficientes com bons dados fotométricos. No entanto, foi possível, com os dados disponíveis, comparar as calibrações fotométricas existentes e refinar ligeiramente a melhor delas, como descrito no Capítulo 3.Após este trabalho passei a concentrar-me em técnicas espectroscópicas de obtenção de parâmetros estelares em estrelas M. Tendo em mente esse objetivo, usei espectros HARPS de alta resolução para desenvolver um novo método de medição de linhas espectrais independente do contínuo espectral. Seguidamente, usei este método no desenvolvimento de uma nova calibração de metalicidade e temperatura efectiva em estrelas M na região do visível, através da qual consegui atingir uma precisão de 0.08 dex para a [Fe/H] e de 80 K para a temperatura. Este trabalho está descrito no Capítulo 4.Ao mesmo tempo colaborei na determinação com precisão dos parâmetros da estrela GJ3470 e do seu planeta, onde a minha proficiência na determinação de parâmetros estelares em anãs M teve um papel importante. Os detalhes relacionados com este trabalho de investigação estão descritos no Capítulo 5.

Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia Fire provides a fundamental ecological function to many ecosystems. Nevertheless, in the past decades, the occurrence of very large, severe fires, has called for attention from managers, scientists and society in general. Understanding fire drivers constitutes an important step to identify regions of higher risk, establish priorities for protection, and manage the landscape to increase its fire resilience. The main goal of the present work is to explore relationships between fire, vegetation, topography and meteorology at landscape scale. It applies principal component analysis and circular statistics to determine the existence of spatial patterns in fire perimeter orientation, in two mediterranean climate regions, relying on a 31-year fire atlas for Portugal and 100-year fire atlas for California. Additionally it applies quantile regression to evaluate the relationship between fire size and fire selectivity towards different land cover types, in Portugal. The results presented here reinforce the importance of meteorological conditions as the primary driver of fire spread, at landscape scale and in the regions considered.

Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia Riparian forests are responsible for many functions considered essential to the preservation of the ecological condition of fluvial corridors. The aim of this thesis is to characterize the structural and compositional patterns of the riparian vegetation in relation to its ecological quality using remote detection and geographic information systems. Separability analyses allowed to characterize and distinguish the spectral patterns and divergent optical behavior between the main riparian forests of Portugal. Spectroradiometry analyses enable the identification of the optimal bands for the remote detection of the alien invasive species Arundo donax, giant reed, from the surrounding vegetation, taking into account its seasonal spectral variability. The Geostatistical techniques combined with the application of landscape metrics, in high spatial resolution images, allowed the remote identification of the structural patterns for riparian forests and for the riparian areas invaded by the giant reed. It was obtained a relation between the observed degradation patterns and a gradient of human disturbance in the surrounding areas of fluvial corridors. The combination of the spectral and geometric attributes allowed to increasing giant reed mapping accuracy in riparian habitats, using a semi-automatic technique.

Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia Wildland fires are recurrent events in Europe, with higher incidence in Southern Mediterranean countries. Despite the ancient relationship between fire and environment in this region, changes in fire regime and land use cause damaging impacts. This research investigates the structural factors that drive fire occurrence in Southern Europe and their variability across several countries, focusing on three key aspects: the interactions between fire and landcover, a fundamental component of fire dynamics; the modelling of fire likelihood in the long-term in the most affected-countries; the identification of the global and local drivers of fire density and burned area. The results evidenced the importance of climatic and vegetation conditions throughout the region. The geographical areas and vegetation-types most susceptible to burn were identified, as well as local and regional differences in the influencing factors. Non-summer precipitation and predominance of shrublands and grasslands are significant, at different levels according to the location. Human factors, among which roads density and agricultural activities, were mainly linked with fire ignitions. This research can contribute to the definition of targeted and more efficient fire management strategies for Southern Europe, besides fostering international collaboration, when shared issues among countries can benefit from transnational solutions.

Doutoramento em Engenharia Florestal - Instituto Superior de Agronomia The recent awareness to what would be the climate change consequences, namely in the observed changes in the fire regimes, highlight the urgency for piro-climatic studies. The lack of an historical burnt area dataset to complement recent products, covering the global extent and its full variability,makes it difficult to detect significant trends. Due to the lack of global information before year-2000, a burned area product based on the NOAA Pathfinder AVHRR land (8km) dataset was developed covering the period from 1981 to 1999. As reference we screened the World Fire Atlas dataset, by removing all the non wildfires and false alarm information and we addressed the expected detectable area made by the coarser sensor. Data pre-processing was prefomed by removing the satellite orbital drift trends with empirical mode decomposition and a burned area classification was done based on the Random Forest classification algorithm. Although the developed methodologies allowed to overcome many of the technical difficulties and the results showed high flexibility to cover the full extent of possible fire occurrences, burned areas were characterised by large underestimation. This is mainly explained by the PAL re-sampling procedure and by the limitations of the coarser sensor to detect certain burned scar spatial patterns.

Mestrado em Engenharia Civil No presente trabalho, foram caracterizados diversos tipos de argamassas-cola para aderência de superfícies difíceis. Esta caracterização foi realizada em argamassas em pó, no estado fresco e após endurecimento, de modo a determinar a mais adequada para os objetivos propostos. Posteriormente, foi caracterizada a lâmina cerâmica, com e sem rede no tardoz. Esta caracterização foi realizada tendo em atenção a absorção de água, porosidade aberta, permeabilidade ao vapor de água, perda de massa por calcinação a 500º e 900ºC e avaliação da aderência utilizando a seleção de argamassas realizada anteriormente. Face às diferenças de resultados obtidos nos testes de aderência da lâmina, com e sem rede no tardoz, optou-se pela reconstrução do tardoz da lâmina cerâmica. Esta reconstrução foi realizada variando o tipo de rede, o tipo de cola de fixação e o tipo de agregados colados de modo a melhorar a aderência, sendo posteriormente estudada a aderência com estas novas superfícies. Não tendo sido atingidos os resultados expectáveis, decidiu-se avaliar o processo de secagem e o efeito do pente utilizado na aplicação da argamassa, uma vez que este último influencia na quantidade de argamassa envolvida no processo. Foi ainda avaliada a compatibilidade de cimentos-cola de presa rápida com a lâmina cerâmica. Com o objetivo de avaliar efeitos do processo de hidratação na compatibilidade de materiais e interfaces. Concluídos os primeiros ensaios laboratoriais, foram realizados ensaios ‘in situ’ com lâmina cerâmica de dimensões de 1,0x1,0m e 0,4x0,4m, variando o suporte entre betonilha e lamina cerâmica. Para concluir, realizaram-se ensaios laboratoriais para avaliar a influência da aplicação de primários de aderência, no processo de colagem de lâmina cerâmica. In the present study, various types of adhesive mortars were characterized for the adhesion in difficult surfaces. This characterization was performed in powder, fresh and hardened state, to determine the most suitable mortar for the proposed goals. Later, thin ceramic tiles, with and without the backside grid, was also characterized. This characterization was performed taking into account the water absorption, porosity, water vapour permeability, weight loss on ignition at 500º and 900°C and evaluating the adhesion of mortar using the selection made previously. Given the differences in the obtained results of adhesion tests of the ceramic blade, with and without the backside grid, it was decided to rebuild the backside of the thin tiles. This reconstruction was carried out varying the type of grid, type of adhesive and the type of aggregates bonded in order to improve the adhesion. The adhesion was subsequently studied with these new surfaces. Although the results were not the expected ones, it was decided to assess the drying process and the effect of the comb used in the application of mortar, since this influence the amount of mortar involved in the process. The compatibility of for setting cement-based mortar with the thin tiles was also evaluated. In order to evaluate the effects of the hydration process, in the compatibility of the materials and interfaces. To complete the initial laboratory tests, trials were conducted in situ with thin tiles of dimensions 1,0x1,0m and 0,4x0,4m, using supports like floor screed and thin tiles. At last, laboratory tests were performed to evaluate the influence of application of adhesion primaries in the process of bonding thin tiles.

Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia It is widely known the economic importance of maritime pine, its current distribution area of resulting fundamentally from human activity. This roughly corresponds to the coastal strip stretching from the Tagus and Sado basins to the river Minho, extending inland in the North and Center. The area where we performed this analysis is located in Herdade da Comporta, in particular in forest stands of pine (Pinus pinaster), in a total area of 12 600 ha of which nearly 6900 ha are occupied with this species. Looking at the district of Setúbal and more specifically at our study area, we are faced with one of the most forested areas of the country. Thinking about the strong presence of the maritime pine and its current problems (NMP) a mapping of the evolution of this species in this territory was conducted. The final result obtained is maps with densities of pine from 1999 to 2009. All the exercises have been achieved with the help of ArcView 3.3 or ArcGis 9.3. With this result, it becomes possible in the future to develop new mapping, which will give us the trends and realites of the spatial evolution of the pest.

Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia In Portugal every year thousands of hectares of forest burnt. Thousands of euros are spent annually to fight and prevent fires but the post-fire management is often overlooked and is primarily focused on research. This work, based on a questionnaire carried out at a national level, aims to describe the current post-fire management practices in different forest types from Portugal. In this questionnaire the questions addressed are related to the control of erosion and flood risk, control of pests and weeds and managing the presence of herbivores. Also the management of burned trees and the use of natural or artificial regeneration are taken into account and treated in terms of what is done at the major national forests, the pine trees, oaks, eucalyptus and cork oaks.

Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia Fire is a global phenomenon, acting as an important disturbance process. Africa is one of the continents that has higher fire density, particularly in savanna regions, making it the subject of innumerous studies about fire regime and behavior. Here, a new method of time series analysis called Empirical Mode Decomposition (EMD) was applied to monthly fire counts time series from MODIS Terra/Aqua sensors. The goals were to analyze the differences between the time series from the two instruments (MODIS Terra and Aqua), the differences in the behavior of the active fire time series from the north and south parts of Africa and they‟re relationships with climatic modes (ENSO and IOD). For most of the time series, the application of the EMD resulted in four IMF‟s and a residue. Although there is always an IMF related with seasonality, the physical meaning of the other isn‟t clear. This may be due to various reasons, some related with intrinsic problems of the method, other with the applicability of the method to this type of series.

Tese de doutoramento, Ciências Geofísicas e da Geoinformação (Meteorologia), Universidade de Lisboa, Faculdade de Ciências, 2011 Submitted by Marta Nogueira (mnogueira@reitoria.ul.pt) on 2011-02-10T15:42:52Z No. of bitstreams: 1 ulsd059597_td_Renata_Santos.pdf: 9417355 bytes, checksum: fd26f3af0cbddfdac945118d7562be76 (MD5) Made available in DSpace on 2011-02-10T15:43:02Z (GMT). No. of bitstreams: 1 ulsd059597_td_Renata_Santos.pdf: 9417355 bytes, checksum: fd26f3af0cbddfdac945118d7562be76 (MD5) Previous issue date: 2010 DSA/INPE; Portuguese Foundation of Science and Technology (Fundação para a Ciência e Tecnologia / FCT)(SFRH/BD/21650/2005)

Mestrado em Engenharia Floresta e dos Recursos Naturais - Instituto Superior de Agronomia Vegetation fires are an important source of greenhouse gases emissions to the atmosphere, such as carbon dioxide (CO2), methane (CH4) and nitrogen dioxide (N2O). In order to improve our knowledge on how these gases affect the atmosphere, it is of utmost importance to identify and reduce the uncertainties attached to emissions estimation. Each one of the variables used to calculate the emissions (burnt area, biomass, combustion factor and emission factor) have uncertainties associated with estimation of their values. The uncertainty analysis helps us to understand the variability of the model output. In Portugal, within the large annual variability, between 1990 and 2008, 2003 was the year with the highest amount of greenhouse gases emitted. CO2 was the gas with larger quantities emitted (roughly 5000Gg), however significant amounts of CH4 and N2O, which have higher greenhouse effect potential, were also released (311 and 258Gg CO2eq.). Results of the sensitivity analysis allowed for the identification of emission factor and the combustion factor of shrubs as the variables with higher impact on the variance of the model output. Therefore, it is very important to reduce the uncertainties attached to these variables in order to reduce the variability of the model output.-----------------------------------------Os fogos de vegetação são uma importante fonte de emissão de gases com efeito de estufa, como o dióxido de carbono (CO2), metano (CH4) e óxido nitroso (N2O), sendo essencial conhecer e reduzir as incertezas associadas à estimativa destas emissões. A análise de incerteza permite avaliar a variabilidade do resultado do modelo que está associada às incertezas inerentes a cada uma das variáveis, utilizadas no cálculo das emissões: área ardida, biomassa, factor de combustão e factor de emissão. Em Portugal, a variabilidade anual observada é grande. Entre 1990 e 2008, o ano de 2003 registou a maior quantidade de gases emitidos, com o CO2 como gás emitido em maior quantidade (cerca de 5000Gg). Importa realçar que também foram emitidas quantidades significativas de CH4 e N2O (311 e 258Gg CO2eq., respectivamente), que são gases com um potencial de efeito de estufa muito maior que o do CO2. Em 2008, pelo contrário, registaram-se os valores mais baixos de emissões, devido à pequena extensão de área ardida. A análise de sensibilidade permitiu identificar o factor de emissão para cada composto químico e o factor de combustão da vegetação arbustiva, como as variáveis com maior efeito sobre a variância do resultado do modelo.

Doutoramento em Engenharia Florestal - Instituto Superior de Agronomia The broad geographical range and temporal dynamics of the areas affected by biomass burning require the use of remote sensing for quantitative assessment of the process. Due to the complex factors that interact in the tropical regions, the “Southern Africa Regional Science Initiative” (SAFARI 2000) was developed to investigate the role of biomass burning on the savannas of southern Africa, its impact over the atmosphere, climate and ecology. This was also an opportunity to explore the adequacy of the new MODIS sensor, for burnt area mapping and to produce accurate estimates of other parameters involved in the evaluation of the emission estimates from vegetation fires. Under this framework, two campaigns were developed, in Zambia and Mozambique, to evaluate the spectral and spatial ability of MODIS to detect burnt areas and improve the current burnt area extent and biomass burnt estimates at the regional level. In this thesis we showed that MODIS data has the potential to improve these estimates. Factors such as climate, vegetation and anthropological are also determinants of fire incidence, and understand the pyrogeography is important to incorporate this information on burnt area classification algorithms and biomass burning models. We found non-stationary fire environment relationships in Africa.

Tese de mestrado. Faculdade de Engenharia. Universidade do Porto. 1998

Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia Submitted by Margarida Galamba (galamba@isa.utl.pt) on 2014-02-03T10:26:40Z No. of bitstreams: 1 Tese_Doutoramento_AMGB.pdf: 33792349 bytes, checksum: e92b13d2ba0b3e254de96a5a0bd88b4c (MD5) Made available in DSpace on 2014-02-03T10:26:57Z (GMT). No. of bitstreams: 1 Tese_Doutoramento_AMGB.pdf: 33792349 bytes, checksum: e92b13d2ba0b3e254de96a5a0bd88b4c (MD5) Previous issue date: 2013

Mestrado em Engenharia do Ambiente - Instituto Superior de Agronomia Nowadays the climate change makes more necessary the study of ecosystem dynamics. The Portuguese montado is an ecosystem with very particular characteristics, because is a combined system with pastures and forest, managed by men, and depends on this manage to continue. More than economic value, montado is very important system with a big biodiversity and landscape quality. For this study was propose to study about the seasonal variation of montado, since 2000 to 2012, using remote sensing and vegetation index as tools to analyze the response of montado to different environmental factors, as the precipitation, temperature and relative humidity. The chosen vegetation index was the NDVI (Normalized Difference Vegetation Index), because of all the advantages, and was calculated using MODIS sensor data. To find the relation between our vegetation index vegetation data, and the meteorological variables, was make a time series analysis, and a correlation study of each variable with the vegetation index. The results was satisfactory and was agree with the initial hypotheses. We find that the precipitation is the variable that influences NDVI the most, and this correlation is bigger when we use the accumulative inter-annual and seasonal data instead the original data. The results show the effects of the big drought of 2004 and 2005 too. The remote sensing appears as a very important and critical tool for this study area future and show that this study could be extend with new directions and new research hypotheses

Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia - UL Neste trabalho pretende-se modelar a potência radiativa do fogo, que está relacionada com a intensidade do fogo. O trabalho tem um carácter exploratório e pretende explorar a dinâmica espacial e temporal da intensidade do fogo em função de um conjunto de variáveis ambientais, que poderão estar potencialmente relacionadas com a intensidade do fogo. Explorar quais as variáveis que poderão estar associadas a valores baixos e elevados da potência radiativa do fogo poderá apoiar a tomada de decisões num contexto de fogos controlados que poderá permitir responder a questões de quando e onde se deverá queimar. Os dados referem-se ao ano de 2011. Para cumprir o objectivo proposto utilizaram-se árvores de decisão, implementadas no programa CART. As árvores de decisão foram usadas para modelar a potência radiativa do fogo. Através deste método determinou-se quais as variáveis que exibem uma maior influência na intensidade do fogo N/A

Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia Fire is a natural process and a component of many ecosystems; it is an important factor to ensure the biodiversity in these areas. However, fire is damage for the forests, in recent decades it has increased in the Mediterranean countries due to rural depopulation and climatic conditions. Particularly, Portugal shows a great increase of surface burnt in the first years of this century in relation to the end of twentieth century. Portugal is a country with high forest cover and importance derived from forestry, so that is required every effort to maintain the future of their forests. The analysis of boundaries of the burned areas allows study the correlation between the spatial distribution of fire and land environmental variables, and particularly explain why some areas are maintained in many cases as border fire. This will be the main objective of this study, based on the exploration of the most significant variables to interpret the location of such boundaries in mainland Portugal. By performing statistical analysis of a set of data for large fires in Portugal from 1996 to 2005, has proved the correlation between land use and the boundaries of the fire. The statistical method used is the classification trees, used to obtain accurate prediction models. The analysis results show that most of the boundaries of fires take place in areas of undergrowth

Doutoramento em Engenharia Florestal - Instituto Superior de Agronomia Submitted by Margarida Galamba (galamba@isa.utl.pt) on 2010-04-28T10:16:27Z No. of bitstreams: 1 tese_doutoramento_anasa.pdf: 21927570 bytes, checksum: ec82c96495dbc6a2a3eaff3f8a3194f8 (MD5) Made available in DSpace on 2010-04-28T10:18:36Z (GMT). No. of bitstreams: 1 tese_doutoramento_anasa.pdf: 21927570 bytes, checksum: ec82c96495dbc6a2a3eaff3f8a3194f8 (MD5)

Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia Africa is the single largest continental source of greenhouse gases emissions resulting from biomass burning. This study acknowledges the generally agreed opinion that the occurrence of fires on West Africa savannas is mainly influenced by human factors. It also provides insights into the physical, climatic, and human drivers of fire and their relative importance across Guinea-Bissau. Each cause of fire has a unique spatial and temporal distribution with its own consequences for fire regime in Guinea-Bissau. Satellite remote sensing techniques provide the only realistic means of obtaining fire information at a national scale, thus ensuring consistency in the observation with the possibility of spatially explicit and continuous sampling of the same territory. This work uses 1-km MODIS active fire and burned area products, from 2001 to 2008, supplemented with Landsat data, to describe the fire regime in Guinea-Bissau. Detailed and current information concerning the location and extent of the burnt areas is provided. A high frequency of “early fires”, from bushfires, and “late fires”, predominantly associated with agricultural areas, were identified. This pattern is not present in the entire length of the country and depends heavily on cultural factors - dominant ethnic group. It was estimated a large inter-regional variability in area burned but a pervasive pattern of decrease in area burned in the early dry season and an increase at the end of it.

Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia - UL Vegetation burning has an important impact on the global atmosphere and vegetated land surface. Deforestation fires, peatland fires, and ecosystems with shortening fire return interval contribute substantially to the build-up of atmospheric greenhouse gases affecting environmental quality and the climate system at local and regional scales. Recognition of the role of fire in the Earth system led to its designation as an Essential Climate Variable (ECV), a physical, chemical, or biological variable that has a crucial contribution towards characterization of Earth’s climate. The central task of this thesis was the development of a new global classification and map of fire regimes, using multiple correspondence analysis and hierarchical clustering, and relying on active fire data from the Moderate Resolution Imaging Spectroradiometer (MODIS) MCD14ML product. That work was preceded by study dedicated to a thorough screening and exploratory spatial analysis of the dataset, and led to the development of an improved algorithm for identifying individual active fire clusters, and to global analysis of size inequality in their statistical distributions. In addition to this core research, other continental-global pyrogeography studies were developed, and are presented, dealing with: the time lag between the timing of optimal fire weather conditions and peak fire season dates as a diagnostic of anthropogenic vegetation burning; the spatial non-stationarity in the parameters of the relationship between population density and area burned; and the modulation of weekly cycles of vegetation burning in African croplands by regionally dominant religious affiliation. We hope that this set of studies may constitute a useful contribution to the burgeoning topic of global pyrogeography

Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia In tropical savannas, one of the most fire-prone biomes on Earth, fire management is a continuous and iterative process that can only be effectively achieved with thorough consideration of fire regimes. Based on remotely sensed imagery and in-situ field data, key fire regime components were assessed for tropical savannas of northern Australia (frequency, patchiness, intensity, and severity) and Brazil (frequency). The discrete lognormal model was found to be the best method for modelling fire frequency in tropical savannas, and demonstrated that fire frequency is very high in both countries. In northern Australia, fire patchiness was lower in the late dry season, characterized by shorter and fewer unburned patches, than in the early dry season. Fire intensity and severity were highest in the late dry season. The observed temporal differences are consistent with the hypothesis that climate is the main driver of fire regime seasonality. Fuel load and fuel continuity explained fire regime differences between vegetation types. Fire season was bimodal, with peaks in May and October, related to periods of anthropogenic fire and optimal fire weather conditions. Prescribed burning in the early dry season can increase the patchiness and reduce the intensity of late dry season fires, with substantial benefits for biodiversity and a reduction in greenhouse gas emissions

Doutoramento em Engenharia Florestal - Instituto Superior de Agronomia Vegetation fires actively participate in ecosystem dynamics and atmospheric composition. Their contemporaneous occurrence and impacts – described under the concept of “fire regimes” – is driven by climate, vegetation, and human activities – the components of the “fire triangle”. The gaps in our understanding of those drivers hamper the proper consideration of fires in various domains, including ecosystems management, vegetation modeling, and climate change investigation. This thesis capitalizes on satellite observations to depict the anthropogenic and climatic influence on fire regimes. Fire inter-annual variability is shown to be dominated by large scale climatic patterns, of which the El Niño-Southern Oscillation has the most widespread and long term footprint. Fire frequency and seasonality are more complex, being determined by the interaction of all three factors of the fire triangle. The evaluation of a vegetation-fire model thus reveals significant discrepancies. It suggests a great margin of progress on representing of the anthropogenic factor, supported by the wide range of fire practices identified from fire season dynamics. A model specific to tropical deforestation fires is developed, as a regional application of this thesis contributions. Climate is a forceful safeguard against forest conversion progress, but ongoing environmental changes could revert the situation.