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First lithostratigraphical and palaeontological data from the Carboniferous of Águeda (Aveiro, Portugal)
No full textRESUMO: O Paleozoico da região de Águeda, pertencente à Zona Centro-Ibérica, está localizado na zona de cisalhamento Porto-Tomar-Ferreira do Alentejo e permanece amplamente desconhecido. Neste trabalho são documentados os primeiros dados litoestratigráficos e paleontológicos do Carbonífero da região, o qual representa o limite setentrional da Bacia Carbonífera do Buçaco. A secção estudada, localizada em Souralvo (Bolfiar), corresponde à Formação Vale da Mó, estando representada por duas sequências granodecrescentes de argilitos siltíticos vermelhos, massivos, que passam gradualmente a pelitos laminados cinzentos no topo, às quais se sobrepõem arenitos finos com intercalações silto-argilosas. A associação de fácies indica um ambiente essencialmente lacustre. A associação fossilífera é quase exclusivamente composta por fósseis de vegetais, incluindo representantes de Cordaitopsida (folhas de Cordaites e sementes do tipo Cardiocarpus e Carpolithes), Trigonocarpales (Neuropteris zeilleri e Callipteridium gigas), Marattiales (Pecopteris cyathea e P. cf. arborescens) e Equisetales (Annularia spinulosa e A. sphenophylloides). Embora raros, foram também recolhidos fósseis de bivalves límnicos (Anthraconaia sp.) e identificadas marcas de oviposição endofítica de insetos em folhas de Cordaites, o primeiro registo deste tipo de icnofósseis no Carbonífero de Portugal. A associação está composta inteiramente por espécies conhecidas nos restantes setores da Bacia Carbonífera do Buçaco, indicando uma idade Estefaniano C tardio (ca. Ghzeliano, Pensilvaniano Superior). A raridade e baixa diversidade de pteridopsídeos, bem como a abundância de representantes de flora mesófila (Cordaites e Neuropteris), sugerem adaptação a condições secas, uma tendência reconhecida no final do Estefaniano C.ABSTRACT: The Palaeozoic of the Águeda region, within the Central Iberian Zone, is located in the Porto-Tomar-Ferreira do Alentejo shear zone and remains largely unknown. This work documents the first lithostratigraphical and palaeontological data from the Carboniferous of Águeda, which represents the northernmost limit of the Buçaco Carboniferous Basin. The section studied, located in Souralvo (Bolfiar), is recognized as the Vale da Mó Formation and is represented by two coarsening upwards sequences of massive red silty mudstones, which gradually change to grey shales at the top, overlain by fine sandstones with silty and mudstones fine intercalations. The association of facies essentially indicates a lake system. The fossil assemblage is mainly composed of fossil plants, including representatives of Cordaitopsida (Cordaites-type leaves and Cardiocarpus and Carpolithes-type seeds), Trigonocarpales (Neuropteris zeilleri and Callipteridium gigas), Marattiales (Pecopteris cyathea and P. cf. arborescens) and Equisetales (Annularia spinulosa and A. sphenophylloides). Although rare, fossils of limnic bivalves (Anthraconaia sp.) were also collected and insect endophytic oviposition traces were identified on Cordaites leaves, being the first record of this type of ichnofossils in the Carboniferous of Portugal. The assemblage is composed entirely of species known from the other sectors of the Buçaco Carboniferous Basin, indicating a late Stephanian C age (ca. Ghzelian, Late Pennsylvanian). The rarity and low diversity of pteridopsids, as well as the abundance of representatives of mesophilous flora (Cordaites and Neuropteris), suggest adaptation to dry conditions, a trend recognised at the end of the Stephanian C
New Insights on Gordonia alkanivorans Strain 1B Surface-Active Biomolecules: Gordofactin Properties
No full textABSTRACT: Biosurfactants/bioemulsifiers (BSs/BEs) can be defined as surface-active biomolecules produced by microorganisms with a broad range of applications. In recent years, due to their unique properties like biodegradability, specificity, low toxicity, and relative ease of preparation, these biomolecules have attracted wide interest as an eco-friendly alternative for several industrial sectors, escalating global microbial BS/BE market growth. Recently, Gordonia alkanivorans strain 1B, a bacterium with significant biotechnological potential, well known for its biodesulfurizing properties, carotenoid production, and broad catabolic range, was described as a BS/BE producer. This study focuses on the characterization of the properties of the lipoglycopeptide BSs/BEs produced by strain 1B, henceforth referred to as gordofactin, to better understand its potential and future applications. Strain 1B was cultivated in a chemostat using fructose as a carbon source to stimulate gordofactin production, and different purification methods were tested. The most purified sample, designated as extracted gordofactin, after lyophilization, presented a specific emulsifying activity of 9.5 U/mg and a critical micelle concentration of 13.5 mg/L. FT-IR analysis revealed the presence of basic hydroxyl, carboxyl, ether, amine/amide functional groups, and alkyl aliphatic chains, which is consistent with its lipoglycopeptide nature (60% lipids, 19.6% carbohydrates, and 9% proteins). Gordofactin displayed remarkable stability and retained emulsifying activity across a broad range of temperatures (30 degrees C to 80 degrees C) and pH (pH 3-12). Moreover, a significant tolerance of gordofactin emulsifying activity (EA) to a wide range of NaCl concentrations (1 to 100 g/L) was demonstrated. Although with a great loss of EA in the presence of NaCl concentrations above 2.5%, gordofactin could still tolerate up to 100 g/L NaCl, maintaining about 16% of its initial EA for up to 7 days. Furthermore, gordofactin exhibited growth inhibition against both Gram-positive and Gram-negative bacteria, and it demonstrated concentration-dependent free radical scavenging activity for 2,2-diphenyl-1-picrylhydrazyl (IC50 approximate to 1471 mg/L). These promising features emphasize the robustness and potential of gordofactin as an eco-friendly BS/BE alternative to conventional surfactants/emulsifiers for different industrial applications
Geologia
No full textRESUMO: Portugal, na sua área continental, é formado por três grandes unidades geológicas: o Maciço Antigo, as Orlas Meso-Cenozóicas e as Bacias do Tejo e do Sado. No esboço geológico de Portugal continental apresentado na Figura 2.1, as formações geológicas são escalonadas, de modo simplificado, quanto à sua idade relativa. O Maciço Antigo ocupa cerca de dois terços do território e corresponde a parte de um antigo soco que compreende, essencialmente, séries dominantemente xistentas Pré-Câmbricas e Paleozóicas, estas de idades compreendidas entre o Câmbrico e o Pérmico e em algumas das quais se geraram massas de mármores. Encontra-se localmente coberto por depósitos detríticos discordantes de idade Terciária (ou Cenozóica) e Quaternária, cuja espessura não ultrapassa os 200-300 metros. As séries xistentas do Maciço Antigo foram intruídas, durante fases de intenso magmatismo relacionadas com as orogenias hercínica e alpina, por massas de rochas ígneas de natureza diversa, predominando os granitos. As Orlas sedimentares Meso-Cenozóicas formaram-se, a partir do Pérmico, nas margens continentais a Oeste e a Sul da Península Ibérica, estando relacionadas com os fenómenos tectónicos distensivos que deram lugar à abertura do Oceano Atlântico. Incluem os Períodos Triássico, Jurássico e Cretácico da Era Mesozóica, durante a qual, com relevo para o Jurássico, teve lugar a formação de espessas séries de calcários. Durante o Terciário (ou Cenozóico) a sedimentação foi essencialmente de natureza arenosa e argilosa. Destacam-se as Bacias do Tejo e do Sado que resultaram da instalação de dois importantes golfos subdividindo a Orla Meso-Cenozóica Ocidental durante o Terciário. Funcionaram como zonas de subsidência onde se depositaram espessas sequências de sedimentos de natureza detrítica, com um máximo de 1400 m na Bacia do Tejo. Aí predominam níveis arenosos, mais ou menos grosseiros, com intercalações conglomeráticas e argilosas, e calcários lacustres.info:eu-repo/semantics/publishedVersio
Efeitos da aplicação de biomassa foliar de eucalipto na qualidade do solo: ensaio de campo
No full textABSTRACT: Approximately 30% of Portuguese forests are occupied by eucalyptus (Eucalyptus globulus). As this is a highly flammable invasive species, it is essential to control its proliferation. Thus, the PEST(bio) CIDE project, based on a circular economy perspective, aims to explore the phytotoxic potential of eucalyptus leaves, using its leaf biomass as
an effective and environmentally safe biocide, and its use as a corrective to improve soil properties. It is also expected that the introduction of biomass into the soil will contribute to increase carbon reserves and soil fertility. Thus, it is possible to associate an economic benefit with better management of post-fire regenerated eucalyptus areas. Due to this, a field
trial was carried out to test the effect of biomass application on the soil’s physico-chemical properties. The results indicate that incorporating leaves has a positive effect on some soil properties, mainly in terms of increasing organic matter and available macronutrients.RESUMO: Aproximadamente 30% da floresta portuguesa é ocupada por eucalipto (Eucalyptus globulus). Sendo esta uma espécie invasora altamente inflamável, é fundamental controlar a sua proliferação. Assim, o projeto PEST(bio)CIDE, baseado numa perspetiva de economia circular, visa explorar o potencial fitotóxico das folhas de eucalipto, usando a sua biomassa foliar como um biocida eficaz e ambientalmente seguro, e a sua utilização como corretivo para melhorar as propriedades do solo. Esperase
também que a introdução de biomassa no solo contribua para aumentar reservas de carbono e fertilidade do solo. Assim, é possível associar um benefício económico a uma melhor gestão das áreas de eucalipto regeneradas pós-incêndio. Para isto, foi realizado um ensaio de campo para testar o efeito da aplicação da biomassa nas propriedades físico-químicas do solo. Os resultados indicam que a incorporação de folhas tem um efeito positivo em algumas propriedades do solo, principalmente no aumento de
matéria orgânica e macronutrientes disponíveis
Palynology of the Lower Cretaceous of Catefica (Torres Vedras) : state of the art
No full textRESUMO: Apresentam-se resultados de estudos palinológicos realizados no Cretácico Inferior de Catefica. A associação esporo-polínica foi recolhida em depósitos sedimentares da Formação de Almargem, expostos num afloramento, situado entre as localidades de Catefica e Mugideira, aproximadamente a 4 km sul de Torres Vedras (oeste de Portugal). O afloramento consiste em arenitos fluviais com estratificação cruzada e conglomerados, intercalados com níveis argilosos escuros, ricos de restos de vegetais fósseis. Nesta jazida foi reconhecida uma palinoflora rica e bem preservada, que contribui para a reconstrução da diversidade vegetal e para esclarecer as condições ambientais da região. A palinoflora é dominada por esporos de fetos e pólenes de gimnospérmicas. Os pólenes de angiospérmicas são relativamente comuns, mas subordinados entre os palinomorfos. Os dados palinológicos apontam para a presença de condições húmidas, relacionadas com ambiente fluvial pouco profundo. Além disso, a ocorrência de componentes xerófitos e de grãos de pólen bissacados, reflecte a presença de vegetação de coníferas em clima relativamente seco.ABSTRACT: Results of palynological studies on the Lower Cretaceous of Catefica site are presented here. The spore-pollen assemblage was extracted from sedimentary deposits of the Almargem Formation exposed in a road cut, between the villages of Catefica and Mugideira, ca. 4 km south of Torres Vedras (western Portugal). The outcrop consists of fluvial cross-bedded sandstones and minor conglomerates, intercalated with dark organic mud levels. It was founded a rich and generally well preserved palynoflora that contributes to the reconstruction of the vegetation diversity and to enlighten the environmental conditions. The palynoflora is dominated by fern spores and gymnosperm pollen. Angiosperm pollen grains are relatively common, but subordinate among the palynomorphs. The available palynological data supports the evidence of humid conditions related to a shallow fluvial environment. Moreover, the presence of xerophytic components, together with bisaccate pollen grains, reflects the presence of conifer vegetation in a relatively dry climate
Optimizing bacterial nanocellulose production from eucalyptus bark: A circular approach to wastewater management and resource recovery
No full textABSTRACT: The production cost of bacterial nanocellulose (BNC) is a major limitation to its widespread use. However, this limitation can be addressed by using alternative low-cost substrates and high-yield strains. Agro-industrial wastederived substrates offer a cost-effective and sustainable solution, but their high organic load often requires additional downstream wastewater treatments. Here, we optimized static BNC production using eucalyptus bark hydrolysate (EBH) as a low-cost carbon source and proposed a circular approach for wastewater management. Optimization was performed using response surface methodology - central composite design. The optimized EBH medium yielded a 39.7-fold increase compared to standard medium, with a maximum BNC production of 8.29 f 0.21 g/L. Fermentation wastewater only (WaF) and combined with BNC washing streams (WaW) revealed high levels of organic matter, namely chemical oxygen demand (COD) of 159.0 f 2.0 and 41.1 f 0.3 g/L, and volatile solids (VS) of 99.5 f 0.9 and 26.3 f 0.2 g/L, respectively, requiring treatment before disposal. A sequential anaerobic-aerobic digestion was investigated for wastewater treatment and valorisation. Anaerobic digestion proved to be effective in treating the wastewater: methanization percentages over 87 % were achieved, and methane productions of 486 f 2 and 544 f 30 L/kg VS were obtained from WaF and WaW, respectively. Subsequent aerobic treatment was unsuccessful in further reducing COD levels (approximately 1.5 g/L). Notably, treated wastewater was recycled into the production process up to 45 % without affecting the BNC yield. This study provides valuable insights into the optimization of BNC production from lignocellulosic biomass and the management of wastewater streams, contributing to the development of a more sustainable and economically viable process
Glacial and geomorphological cartography and paleoglacial limits of Serra Amarela
No full textRESUMO: A investigação geomorfológica sobre a glaciação plistocénica da Serra Amarela, inserida no Parque Nacional da Peneda-Gerês (PNPG), remonta ao início da década de 80. No entanto, os limites da área glaciada permanecem imprecisos para a reconstrução glaciária. Esta montanha de baixa altitude com 1361 m caracteriza-se pela sua topografia assimétrica
W-E e predomínio de litologia granítica sobre afloramentos metamórficos restritos. As encostas ocidentais íngremes são dominadas por formas de relevo relíquias fluviais e periglaciárias. Por outro lado, as encostas orientais íngremes revelam evidências de erosão e depósitos glaciários anteriores, particularmente no circo glaciário do Ramisquedo. O presente estudo apresenta um novo mapa geomorfológico da Serra Amarela, utilizando dados LiDAR de elevada resolução espacial e interpretações das formas de relevo validadas por trabalho de campo. Os dados recolhidos, relativamente à glaciação da Serra Amarela, permitiram, metricamente, definir: a Máxima Extensão Glaciária (MEG) de 1 km2, a espessura máxima de gelo de 92 m, o volume estimado em 26,4 hm3, e posicionar a ELA-AABR nos 1122 m.ABSTRACT: Geomorphological research on the Pleistocene glaciation of Serra Amarela, located in the Peneda-Gerês National Park (PNPG), dates to the early 1980s. However, the boundaries of the glaciated area remain imprecise for glacial reconstruction. This low-lying mountain with 1361 m of altitude is characterized by its W-E asymmetric topography and by the dominance of granitic lithology and sparse metamorphic rocks. Fluvial and relict periglacial landforms dominate the steep western slopes. On the other hand, the steep eastern slopes reveal evidence of former glacial activity with traces of erosion and deposits, particularly in the Ramisquedo glacial cirque. The current study introduces a new geomorphological map of Serra Amarela, created using high-resolution LiDAR data and supplemented with interpretations of landforms and validated through fieldwork. The collected data, on the glaciation of Serra Amarela, allowed us to make several key measurements: the Maximum Glacial Extent (MGE) at 1 km², the maximum ice thickness at 92 m, an estimated volume of 26,4 hm3, and the ELA-AABR at 1122 m
Portugal Offshore Wind, Green Hydrogen, and Sustainable Fuels: Power-to-X Pathways
No full textABSTRACT: Portugal has a vast coastal area and significant offshore wind resources. The country has set ambitious targets and designated specific areas for offshore wind development. Current national policies are actively encouraging investment in these projects. This report compiles the latest strategies for offshore wind and green hydrogen in Portugal. It introduces the Power-to-X (P2X) concept, explores potential offshore wind-based P2X business models, and outlines the key processes and technologies involved. It also maps potential consumers of green hydrogen, along with the associated supply chains for hydrogen and sustainable fuels. A techno-economic analysis was conducted to identify viable pathways for Portugal. This involved selecting one of the planned offshore wind zones and, based on its location and potential capacity, determining the optimal onshore site and scale for a hydrogen and sustainable fuels hub. The report presents a comparative evaluation of seven scenarios, offering valuable insights for both public and private sector stakeholders.RESUMO: Portugal tem uma vasta área costeira e recursos eólicos offshore significativos. O país estabeleceu metas ambiciosas e designou áreas específicas para o desenvolvimento eólico offshore. As atuais políticas nacionais incentivam ativamente o investimento nestes projetos. Este relatório compila as mais recentes estratégias para a energia eólica offshore e o hidrogénio verde em Portugal. Introduz o conceito Power-to-X (P2X), explora potenciais modelos de negócio P2X baseados em energia eólica offshore e descreve os principais processos e tecnologias envolvidos. Também mapeia potenciais consumidores de hidrogénio verde, juntamente com as cadeias de abastecimento associadas para o hidrogénio e os combustíveis sustentáveis. Foi realizada uma análise técnico-económica para identificar rotas viáveis para Portugal. O relatório envolveu a seleção de uma das zonas eólicas offshore planejadas e, com base em sua localização e capacidade potencial, determinou-se o local e a escala ideais em terra para uma central de produção de hidrogênio e combustíveis sustentáveis. O relatório apresenta uma avaliação comparativa de sete cenários, oferecendo informações valiosas para atores dos setores público e privado
Overtopping and coastal flooding on the mainland Portugal: territorial complexity and diversity of impacts
No full textRESUMO: Portugal Continental apresenta uma zona costeira extensa, diversificada e complexa. Essa diversidade dá origem a diversas características geológicas e geomorfológicas que suportam diferentes densidades de ocupação humana e uma variedade de atividades, de uso e de ocupação do solo. A crescente ocupação antrópica da zona costeira nas últimas sete
décadas originou um conflito com a dinâmica natural dessas áreas. Nas últimas décadas, o litoral de Portugal Continental tem sido frequentemente afetado por galgamentos e inundações costeiras. Com base na divisão da zona costeira em três tipologias principais distintas (costa baixa arenosa, arriba e costa de transição), o objetivo deste trabalho é compreender os
impactos de ocorrências de galgamentos e inundações costeiras entre 1980 e 2018 que afetaram as diferentes tipologias. Os resultados evidenciam o maior número de ocorrências relacionadas com litorais arenosos baixos e de transição, permitindo identificar e diferenciar impactos nas diferentes tipologias costeiras.ABSTRACT: The mainland of Portugal presents an extensive, diversified and complex coastal zone. This diversity gives rise to diverse geologic and geomorphologic features that support different densities of human occupancy and a wide range of land uses and activities. In the last seven decades, the increasing of the coastal zone anthropic occupation led to a conflict with the natural dynamics of these areas. In the last decades, the coast of mainland Portugal has often been affected by overtopping and coastal flooding processes. Based on the division of the coastal zone into three main distinct typologies (low sandy coast, cliff coast and transitional coast), the aim of this work is to understand the impacts resulting from coastal floods and overtopping between 1980 and 2018 affecting the different typologies. The results show that the higher number of occurrences are related to the low sandy and transitional coast allowing to identify and differentiate impacts on the different coastal typologies
On the Integration of Hydrogen in multipurpose wave energy platforms
No full textABSTRACT: his work presents an integrated numerical modelling approach implemented in Modelica language, which combines a multipurpose wave energy floating platform made of multiple oscillating water columns and the production and storage of green hydrogen in the same platform. The modelling approach comprised the simulation of the platform in WAMIT from which the hydrodynamic coefficients were obtained that serve as input for the integrated model implemented in Modelica. The Cherry Library for electrolysis processes and new modules developed in this work for storage were used and coupled to a model for the five-oscillating-water-column floating platform. The optimisation of hydrogen production based on hydrodynamic performance and energy conversion from waves off the coast of Portugal was conducted to identify optimal green hydrogen production parameters. The operational performance of the system was studied in detail for four representative days of the seasons to estimate optimal production of green hydrogen from ocean waves under those conditions. Dispatch of hydrogen and its conversion to other sustainable fuels, such as methanol or Ammonia are also discussed in terms of the total levelised cost of hydrogen (LCOH). A new tool developed at the National Laboratory for Energy and Geology was implemented to estimate costs. Results are still under progress