Asteroids Deep Ocean Impact and the Short­Term Consequences to the Portuguese Territory and Population

The impact of asteroids is an established global threat. Every location on Earth has a similar, a priori likelihood of an asteroid impact, which is limited by the current humankind’s knowledge. As Earth’s surface is mostly water, a water asteroid impact is twice as likely as a ground impact. Ocean impacts are naturally more distant from populated areas but can still pose a significant threat. Impact events have a low probability but high consequences making them a hard concept to the public as such happenings do not occur in the day­to­day life. Even though asteroid impacts have been proven to be lethal in the past, increasing public awareness to this hazard is still needed. The potential global devastation obliges mitigation measures that would come naturally with the awareness. In this dissertation, an ocean asteroid impact was assumed and the immediate impact effects were assessed for the Portuguese municipalities. The impact location was set in a midpoint between mainland Portugal, Azores and Madeira islands. All asteroids were assumed to impact the Earth at a 45 degrees angle. The study covers seismic shaking, overpressure, ejecta deposit, thermal radiation and tsunami waves; as well as the possible global implications on Earth, in terms of orbit disturbance, change in rotation period, axis tilt variation, and lost mass. The vulnerabilities and casualties for each individual municipality and each impact effect were also estimated. In an asteroid ocean impact far from coastal regions, the ejecta deposit and seismic shaking are the less significant effects and can be disregarded. The thermal radiation has a small reach and can be disregarded for minor asteroids. The shock wave is experienced for all three impacts, but its damage is mostly structural. The tsunami is by far the biggest threat in an asteroid impact on the ocean.O impacto de asteroides é uma ameaça global estabelecida. Cada local na Terra tem uma probabilidade de impacto de asteroides, à partida semelhante, que é limitada pelo conhecimento atual da humanidade. Como a superfície da Terra é maioritariamente água, um impacto de asteroides na água é duas vezes mais provável do que um impacto no solo. Os impactos no oceano estão naturalmente mais distantes das áreas povoadas, mas podem ainda representar uma ameaça significativa. Os impactos têm probabilidades baixas, mas consequências elevadas, tornando­os um conceito difícil para o público, uma vez que tais acontecimentos não acontecem no dia a dia. Embora os impactos de asteroides tenham provado ser letais no passado, ainda é necessário aumentar a consciência pública para este perigo. A potencial devastação global obriga a medidas de mitigação que viriam naturalmente com a consciencialização. Nesta dissertação, foi assumido um impacto de asteroides no oceano e os efeitos imediatos do impacto foram avaliados para os municípios portugueses. A localização do impacto foi fixa num ponto médio entre Portugal Continental, e as ilhas dos Açores e da Madeira. Foi assumido que todos os asteroides impactariam a Terra com um ângulo de 45 graus. O estudo abrange abalos sísmicos, ondas de pressão, depósito de ejeta, radiação térmica e ondas de tsunami; bem como as possíveis implicações globais na Terra, a perturbação da órbita, mudança no período de rotação, variação da inclinação do eixo, e perda de massa. Foram também estimadas as vulnerabilidades e fatalidades para cada município e cada efeito de impacto. Num impacto de asteroides no oceano, longe das regiões costeiras, o depósito de ejeta e o abalo sísmico são os efeitos menos significativos e podem ser ignorados. A radiação térmica tem um curto alcance e pode ser desconsiderada para os asteroides menores. A onda de pressão é experienciada para os três impactos, mas os seus danos são, na sua maioria, estruturais. O tsunami é de longe a maior ameaça dum impacto de asteroides no oceano

Elements of the metacommunity structure : comparison across multiple metacommunities

Les « Éléments de la Structure des Metacommunautés » (EMS) est un outil analytique puissant pour l'évaluation des patrons de distributions d'espèces dans l'espace géographique ou environnementale; par contre, cette technique est encore sous-utilisée parmi les études écologiques. L'objectif de cette étude est d'évaluer les mécanismes structurants les patrons de distributions d'espèces de poissons de lacs boréaux à des multiples échelles en appliquant la technique EMS sur la Ontario Fish Distribution Database, une base de données contenant des informations sur la présence-absence des espèces de poissons de plus de 9000 lacs de l'Ontario ainsi que leurs positions géographiques. Pour chaque lac, l'information sur les variables environnementales on été obtenue grâce au Lake lnventory Database (LINY) et des indices spatiaux, comme la connectivité entre les lacs et leur distance aux refuges postglaciaires, ont été calculés à partir d'informations géographiques. Puis, la relation phylogénétique des espèces et leurs niches B on été estimés pour comprendre le rôle des espèces dans l'assemblage des communautés et formation des metacommunautés. Dans le premier chapitre, la technique EMS a indiqué que nestedness et Clementsian gradients sont les patrons de distributions les plus courants parmi les bassins versants. La pluparts des patrons nestedness se situent dans des bassins de faible énergie contenant des grands lacs et localisés dans de hautes latitudes tandis que les patrons Clementsian gradients sont rencontrés dans des conditions opposés. À l'échelle des bassins, les variables environnementales expliquent en moyenne 9.1% de la variation dans la distribution des espèces pour les deux type de patrons contre moins de 3.5% pour les variables spatiales. À l'échelle provinciale, la variation dans la distribution des espèces est expliquée principalement par les variables environnementales structurées spatialement (29,26%) suivit des variables environnementales indépendantes de l'espace (10.80%). Des tests statistiques suggèrent que le taux de changement dans la composition des communautés, la caractéristique qui mieux distingue les deux patrons, augmente du nord vers le sud, influencé principalement par la latitude et les variables associées (e.g., température). Dans le second chapitre, les résultats indiquent que, à l'échelle du bassin versant, la sous-dispersion phylogénétique prédomine tandis que la sur-dispersion phylogénétique est plus observée à l'échelle locale. La structure phylogénétique et de niche des communautés sont principalement influencés par la taille des lacs, les variables liées à l'énergie (e.g., température, degré-jour de croissance) et la latitude. Dans les régions du Nord, il y a des taux élevés de chevauchement des niches et de plus grande distance phylogénétique entre les espèces qui cohabitent alors que dans les bassins versants du Sud on rencontre le patron inverse. \ud ______________________________________________________________________________ \ud MOTS-CLÉS DE L’AUTEUR : EMS, analyse de correspondance, Clementsian gradients, distribution d'espèces, nestedness, species turnover, structure phylogénétique, niche, gradient environnementa

The design and use of annual budgets to cope with uncertainty

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and EconomicsFor centuries, annual budgets have played a central key role in most organizations serving the main purposes of planning and control. Yet, more recently the budgeting practice has been subject to severe criticisms, among which stands its ineffectiveness to deal with uncertainty. In order to avoid some of the major problems associated with the preparation and usage of budgets, two alternative approaches have been proposed: Better Budgeting and Beyond Budgeting. This study aims to understand which factors companies perceive as uncertainty, and how budgets, either in their traditional form or through new approaches, might be able to help companies deal with them. To do so, two companies with different dimensions, operating in different business sectors and thus subject to different economic contexts were analyzed. Evidence collected seems to indicate that companies are indeed taking a new approach to budgeting, either simplifying it or complementing it with other techniques. The Balanced Scorecard, due to its capacity to link the short with the long-term strategy as well as to link different perspectives of the companies, comes up as one of the most useful techniques to complement budgets to face uncertainty

Interaction between chromate and salicylic acid and its effects on growth and photosynthetic parameters of pea (Pisum sativum L.) seedlings

Plant growth and some phisiological parameters were investigated in plants exposed to diverse chromium concentrations in the presence or absence of salicylic acid treatment

Rocks, minerals, and microscopes: a multimedia application

During the last two decades of the 20th century the boom of the Information Society changed the usual way of teaching and learning. Computers contributed to better classes allowing teachers to make high-quality presentations and eliminating old transparencies and slide collections. The use of multimedia resources, downloaded from the Internet or based on CD-ROM, constitutes a major advantage for the educational system. Unfortunately, many teachers were not able to take advantage of this technological advance due to several factors, namely: bad conditions in schools, resistance to/afraid of using computers, high cost of equipments, and deficient lifelong formation. Geology teaching can be improved by using multimedia materials because geological processes can be better understood as factors like time and scale can be easily simulated. The edition of educational CD-ROMs dedicated to Earth Sciences triggered in the beginning of the nineties. Nevertheless, during the last couple of years, the number of new educational geology-dedicated CD-ROMs decreased. The diversity of subjects is also rather limited. In 2003 the present authors published in a new CD-ROM designated for preuniversity teachers and students entitled ?Rocks and Minerals from Portugal under the Microscope?. This CD-ROM followed a previous on-line version (very simplified and available at http://www.dct.uminho.pt/eng/rpmic_eng/index.html). The CD-ROM helps the visualization of thin sections of rocks and minerals in the lack of polarizing microscopes in classrooms. It also allows self-studying and teachers presentations during classes. This multimedia application describes the preparation of thin sections and the main characteristics of polarizing microscopes by using video support. The observation of thin sections uses QuickTime? technology simulating true microscopical observations in rotating stages viewed with crossed and parallel polars. Each rock specimen is presented with its main characteristics: name, mineralogical composition, texture, structure, place of sampling, and photographs of a hand sample and of the outcrop. The simulation of minerals observation is complemented with information regarding name, chemical composition, crystalline system, cleavage, hardness, color, and industrial applications. Taking advantage of the interactivity and multimedia resources, this CD-ROM can increase the interest of students in the study of rocks and minerals and hence raising awareness of geology

Photosynthetic parameters in zinc-deficient pecan [Carya illinoinensis (Wangenh) C. Koch, cv Sioux] leaves

Assessment of CO2 assimilation rate, chlorophyll content and stomatal conductance on control plants with diverse leaf Zn-concentration

Remote sensing in post-fire impact assessment and vegetation recovery monitoring

Although wildfires are considered an integral part of many terrestrial ecosystems, their regimes have been altered by human activities. With the increased occurrence of droughts, resulting from climate change, the frequency and intensity of fires are expected to increase in many areas, making our capacity to manage them more difficult in the near future. From an ecological perspective, fires can be considered as repetitive and common disturbances leading to a complete transformation of the ecosystem, particularly in its floristic composition. In addition, fires can affect a large variety of ecosystem processes, altering the ecological cycling of nutrients, affecting the natural cycle of vegetation succession and altering organic matter turnover. However, the impacts of fires on ecological processes and local biodiversity vary greatly among regions, with implications for management and restoration. Precise information about the extent and type of fire and also on the post-fire vegetation recovery is, therefore, required for the estimation of ecological and economic losses. Satellite observations are a valuable tool for the monitoring of dynamic processes occurring at the earth surface because of their synoptic coverage and regular temporal sampling. However, classical methods for change detection are often not capable of detecting land cover changes within time series that are heavily influenced by seasonal climatic variations. In this study, we mapped wildfires (occurring from 2009 till 2011) at the Cávado River basin (NE Portugal) and analyzed vegetation recovery in a Landsat time series acquired from 2004 to 2015. We focused our attention on the dynamics of vegetation recovery using FAPAR vegetation Index representing the fraction of incoming solar radiation in the photosynthetically active radiation that is absorbed by the green parts of the canopy. Specifically, we assessed: 1) the fire severity and effect, detecting changes within the trend and seasonal components of time series; 2) the vegetation recovery based on Recovery Trend Index and Cumulative Relative Recovery Index. Our findings show the importance of remote sensing data series in the assessment of the fire severity and evaluation of the degree of post-fire recovery. Furthermore, the use of remote sensing improved our ability to i) assess post-fire impacts accurately, ii) identify the territory segments at risk from exposure, and iii) develop and plan novel mitigation strategies to reduce potential wildfire impacts that might be used to promote vegetation recovery and conserve regional biodiversit

New methodologies for the promotion of Geological Heritage using multimedia technology, 3D and augmented reality.

[Excerpt] The Internet and several hardware and software options that are currently available are very efficient ways for the promotion of geoparks, geoheritage and geosciences. The aim of this paper is to present a new and interactive way of gathering data into a website, based on several new web and photogrammetric technologies, applied to the Terras de Cavaleiros Global Geopark (Portugal). [...]info:eu-repo/semantics/publishedVersio

Is It worth assessing geodiversity numerically? A comparative analysis between quantitative and qualitative approaches in Miguel Pereira Municipality, Rio de Janeiro, Brazil

The interest in the cartographic representation of geodiversity has grown in recent years. However, the application of geodiversity maps in nature conservation and territorial management policies is still under study, especially concerning quantitative methodologies and geodiversity indices. Aiming to contribute to this topic, a set of correlation analyses were performed between quantitative and qualitative maps, as well as correlations between these and sites of geological interest, land-use, and vegetation maps using Miguel Pereira municipality, Rio de Janeiro, Brazil, as a study area. A geodiversity index map (quantitative approach) was used, and a geodiversity map (qualitative approach) was produced based on GIS procedures and tools through a counting technique and the association between landforms and, geology, soils, and hydrology, respectively. The geodiversity map showed a better correlation between geodiversity and the other nature and anthropic elements, while the quantitative assessment, although having a positive correlation with those elements, showed a weak or very weak correlation. The cartographic outputs in geodiversity units (qualitative approach) best supported this correlative analysis highlighting its use in land-use and nature conservation management. In contrast, the geodiversity index map showed complementary information and could be combined with the qualitative approach for more sustained results.The authors are grateful to CPRM (Servico Geologico do Brasil) and DRM-RJ (Departamento de Recursos Minerais do Estado do Rio de Janeiro) for providing data of the study area and to the Department of Geology of the Federal University of Rio de Janeiro (UFRJ) for providing financial support for the fieldwork