Geotecnia urbana da zona ribeirinha de Vila Nova de Gaia (Cais de Gaia, Santa Marinha – Lavadores, Canidelo): uma avaliação preliminar

Mestrado em Engenharia Geotécnica e Geoambiente

Contributions to the Eocene palaeontology and stratigraphy of Beira Alta, Portugal II - New Late Eocene mammalian remnants from Coja (Portugal) and the presence of Palaeotherium magnum Cuvier

The presence of Palaeotherium magnum in the fauna from Coja is recorded. It is well in agreement with the earlier reporting to the Montmartre level from the Ludian stage. Field data as well as compatibility with the remaining taxa and the identical fossilization of all the specimens indicate that all the vertebrate fossils come from the same horizon in the lithostratigraphic unit "Arcoses de Côja".

Mathematical modelling of shallow flows: closure models drawn from grain-scale mechanics of sediment transport and flow hydrodynamics

Canadian Journal of Civil Engineering 36(10) 1605–16

Estudo da antiga mina de volfrâmio das Aveleiras (Mire de Tibães): cartografia geotécnica e avaliação geomecânica

Este trabalho tem como objetivo sublinhar a importância de um estudo geológico‐geotécnico para apoiar a cartografia geotécnica do maciço rochoso subterrâneo da antiga mina de volfrâmio das Aveleiras (Mosteiro de Tibães, Braga). Foi realizado um trabalho de campo sistemático, ao longo de uma rede de galerias subterrâneas com uma extensão aproximada de 155 m. Estas galerias são constituídas, principalmente, por rochas metassedimentares, embora aflorem rochas graníticas num pequeno trecho de uma das galerias. A técnica de amostragem linear de descontinuidades aplicada ao grau de compartimentação do maciço rochoso esteve na base de todos os dados geológicos, geotécnicos e geomecânicos. Além disso, foram coligidos e integrados os dados de campanhas de campo anteriores, realizadas entre 2006 e 2011. Foram igualmente descritos os métodos de avaliação dos dados de campo, bem como a análise estatística dos parâmetros geológico‐geotécnicos. O zonamento geotécnico do maciço rochoso das Aveleiras foi desenvolvido tendo em conta o comportamento do maciço rochoso in situ, e foi apoiado por ensaios laboratoriais de resistência do material‐rocha através do Ensaio de Carga Pontual. Apresenta‐se uma proposta preliminar de zonamento geomecânico com o objectivo de apoiar o projeto de engenharia de maciços rochosos.

Influence of abiotic stress factors on VOCs emission from Portuguese rice paddy fields: relation with increased climate change

Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente Perfil de Gestão de Sistemas Ambientais

Population Dynamics Modeling of Arapaima gigas

Pirarucu (Arapaima gigas) has been of the most important natural fishing resources of the Amazon region. Due to its economic importance, and the necessity to preserve the species hand, field research concerning the habits and behavior of the pirarucu has been increasing for the last 20 years. The aim of this paper is to present a mathematical model for the pirarucu population dynamics considering the species peculiarities, particularly the male parental care over the offspring. The solution of the dynamical systems indicates three possible equilibrium points for the population. The first corresponds to extinction; the third corresponds to a stable population close to the environmental carrying capacity. The second corresponds to an unstable equilibrium located between extinction and full use of the carrying capacity. It is shown that lack of males’ parental care closes the gap between the point corresponding to the unstable equilibrium and the point of stable non-trivial equilibrium. If guarding failure reaches a critical point the two points coincide and the population tends irreversibly to extinction. If some event tends to destabilize the population equilibrium, as for instance inadequate parental care, the model responds in such a way as to restore the trajectory towards the stable equilibrium point avoiding the route to extinction. The parameters introduced to solve the system of equations are partially derived from limited but reliable field data collected at the Mamirauá Sustainable Development Reserve (MSDR) in the Brazilian Amazonian Region.

Development of an integrated approach to reliability management and operation

The research described in this thesis has been developed as a part of the Reliability and Field Data Management for Multi-component Products (REFIDAM) Project. This project was founded under the Applied Research Grants Scheme administered by Enterprise Ireland. The project was a partnership between Galway-Mayo Institute of Technology and Thermo King Europe. The project aimed to develop a system in order to manage the information required for reliability assessment and improvement of multi-component products, by establishing information flows within the company and information exchange with fleet users.

Development of a life cycle management system for remote products.

The research described in this thesis has been developed as a part of the Reliability and Field Data Management for Multi-Component Products (REFIDAM) Project. This project was funded under the Applied Research Grants Scheme administered by Enterprise Ireland. The project was a partnership between Galway-Mayo Institute of Technology and an industrial company, Thermo King Europe. The project aimed to develop a system to manage the information required for maintenance costing, cost of ownership, reliability assessment and improvement of multi-component products, by establishing information flows between the customer network and across the Thermo King organisation.

3D geoelectrical monitoring to follow hydric soil behaviour during rainfall

RESUME Durant les dernières années, les méthodes électriques ont souvent été utilisées pour l'investigation des structures de subsurface. L'imagerie électrique (Electrical Resistivity Tomography, ERT) est une technique de prospection non-invasive et spatialement intégrée. La méthode ERT a subi des améliorations significatives avec le développement de nouveaux algorithmes d'inversion et le perfectionnement des techniques d'acquisition. La technologie multicanale et les ordinateurs de dernière génération permettent la collecte et le traitement de données en quelques heures. Les domaines d'application sont nombreux et divers: géologie et hydrogéologie, génie civil et géotechnique, archéologie et études environnementales. En particulier, les méthodes électriques sont souvent employées dans l'étude hydrologique de la zone vadose. Le but de ce travail est le développement d'un système de monitorage 3D automatique, non- invasif, fiable, peu coûteux, basé sur une technique multicanale et approprié pour suivre les variations de résistivité électrique dans le sous-sol lors d'événements pluvieux. En raison des limitations techniques et afin d'éviter toute perturbation physique dans la subsurface, ce dispositif de mesure emploie une installation non-conventionnelle, où toutes les électrodes de courant sont placées au bord de la zone d'étude. Le dispositif le plus approprié pour suivre les variations verticales et latérales de la résistivité électrique à partir d'une installation permanente a été choisi à l'aide de modélisations numériques. Les résultats démontrent que le dispositif pôle-dipôle offre une meilleure résolution que le dispositif pôle-pôle et plus apte à détecter les variations latérales et verticales de la résistivité électrique, et cela malgré la configuration non-conventionnelle des électrodes. Pour tester l'efficacité du système proposé, des données de terrain ont été collectées sur un site d'étude expérimental. La technique de monitorage utilisée permet de suivre le processus d'infiltration 3D pendant des événements pluvieux. Une bonne corrélation est observée entre les résultats de modélisation numérique et les données de terrain, confirmant par ailleurs que le dispositif pôle-dipôle offre une meilleure résolution que le dispositif pôle-pôle. La nouvelle technique de monitorage 3D de résistivité électrique permet de caractériser les zones d'écoulement préférentiel et de caractériser le rôle de la lithologie et de la pédologie de manière quantitative dans les processus hydrologiques responsables d'écoulement de crue. ABSTRACT During the last years, electrical methods were often used for the investigation of subsurface structures. Electrical resistivity tomography (ERT) has been reported to be a useful non-invasive and spatially integrative prospecting technique. The ERT method provides significant improvements, with the developments of new inversion algorithms, and the increasing efficiency of data collection techniques. Multichannel technology and powerful computers allow collecting and processing resistivity data within few hours. Application domains are numerous and varied: geology and hydrogeology, civil engineering and geotechnics, archaeology and environmental studies. In particular, electrical methods are commonly used in hydrological studies of the vadose zone. The aim of this study was to develop a multichannel, automatic, non-invasive, reliable and inexpensive 3D monitoring system designed to follow electrical resistivity variations in soil during rainfall. Because of technical limitations and in order to not disturb the subsurface, the proposed measurement device uses a non-conventional electrode set-up, where all the current electrodes are located near the edges of the survey grid. Using numerical modelling, the most appropriate arrays were selected to detect vertical and lateral variations of the electrical resistivity in the framework of a permanent surveying installation system. The results show that a pole-dipole array has a better resolution than a pole-pole array and can successfully follow vertical and lateral resistivity variations despite the non-conventional electrode configuration used. Field data are then collected at a test site to assess the efficiency of the proposed monitoring technique. The system allows following the 3D infiltration processes during a rainfall event. A good correlation between the results of numerical modelling and field data results can be observed since the field pole-dipole data give a better resolution image than the pole-pole data. The new device and technique makes it possible to better characterize the zones of preferential flow and to quantify the role of lithology and pedology in flood- generating hydrological processes.

Derivation of soil-specific streaming potential electrical parameters from hydrodynamic characteristics of partially saturated soils

Water movement in unsaturated soils gives rise to measurable electrical potential differences that are related to the flow direction and volumetric fluxes, as well as to the soil properties themselves. Laboratory and field data suggest that these so-called streaming potentials may be several orders of magnitudes larger than theoretical predictions that only consider the influence of the relative permeability and electrical conductivity on the self potential (SP) data. Recent work has improved predictions somewhat by considering how the volumetric excess charge in the pore space scales with the inverse of water saturation. We present a new theoretical approach that uses the flux-averaged excess charge, not the volumetric excess charge, to predict streaming potentials. We present relationships for how this effective excess charge varies with water saturation for typical soil properties using either the water retention or the relative permeability function. We find large differences between soil types and the predictions based on the relative permeability function display the best agreement with field data. The new relationships better explain laboratory data than previous work and allow us to predict the recorded magnitudes of the streaming potentials following a rainfall event in sandy loam, whereas previous models predict values that are three orders of magnitude too small. We suggest that the strong signals in unsaturated media can be used to gain information about fluxes (including very small ones related to film flow), but also to constrain the relative permeability function, the water retention curve, and the relative electrical conductivity function.

Threats from climate change to terrestrial vertebrate hotspots in europe.

We identified hotspots of terrestrial vertebrate species diversity in Europe and adjacent islands. Moreover, we assessed the extent to which by the end of the 21(st) century such hotspots will be exposed to average monthly temperature and precipitation patterns which can be regarded as extreme if compared to the climate experienced during 1950-2000. In particular, we considered the entire European sub-continent plus Turkey and a total of 1149 species of terrestrial vertebrates. For each species, we developed species-specific expert-based distribution models (validated against field data) which we used to calculate species richness maps for mammals, breeding birds, amphibians, and reptiles. Considering four global circulation model outputs and three emission scenarios, we generated an index of risk of exposure to extreme climates, and we used a bivariate local Moran's I to identify the areas with a significant association between hotspots of diversity and high risk of exposure to extreme climates. Our results outline that the Mediterranean basin represents both an important hotspot for biodiversity and especially for threatened species for all taxa. In particular, the Iberian and Italian peninsulas host particularly high species richness as measured over all groups, while the eastern Mediterranean basin is particularly rich in amphibians and reptiles; the islands (both Macaronesian and Mediterranean) host the highest richness of threatened species for all taxa occurs. Our results suggest that the main hotspots of biodiversity for terrestrial vertebrates may be extensively influenced by the climate change projected to occur over the coming decades, especially in the Mediterranean bioregion, posing serious concerns for biodiversity conservation.

Modelling the distribution of bats in relation to landscape structure in a temperate mountain environment

1. Landscape modification is often considered the principal cause of population decline in many bat species. Thus, schemes for bat conservation rely heavily on knowledge about species-landscape relationships. So far, however, few studies have quantified the possible influence of landscape structure on large-scale spatial patterns in bat communities. 2. This study presents quantitative models that use landscape structure to predict (i) spatial patterns in overall community composition and (ii) individual species' distributions through canonical correspondence analysis and generalized linear models, respectively. A geographical information system (GIS) was then used to draw up maps of (i) overall community patterns and (ii) distribution of potential species' habitats. These models relied on field data from the Swiss Jura mountains. 3. Fight descriptors of landscape structure accounted for 30% of the variation in bat community composition. For some species, more than 60% of the variance in distribution could be explained by landscape structure. Elevation, forest or woodland cover, lakes and suburbs, were the most frequent predictors. 4. This study shows that community composition in bats is related to landscape structure through species-specific relationships to resources. Due to their nocturnal activities and the difficulties of remote identification, a comprehensive bat census is rarely possible, and we suggest that predictive modelling of the type described here provides an indispensable conservation tool.

Creació de recursos digitals per a la innovació docent en Geologia Estructural i Tectònica

El projecte ha estat dedicat a l’elaboració d’una sèrie de recursos didàctics en format digital per a l’ensenyament de les matèries de Geologia Estructural i Tectònica en titulacions universitàries relacionades amb les Ciències de la Terra. L’objectiu és la millora de la formació i del rendiment dels estudiants mitjançant l’elaboració d’activitats de suport no presencials que fomentin l’autoaprenentatge i l’autoregulació per part de l’estudiant. Les activitats intenten aprofitar les noves eines informàtiques disponibles i fomentar l’accés mitjançant la xarxa. El material que s’elabora en el marc del projecte consisteix en: 1) un fons documental d’imatges relacionades amb la Geologia Estructural i la Tectònica amb explicació, disponibles en xarxa i accessibles per motors específics de cerca, 2) un conjunt d’exercicis i casos pràctics, alguns d’ells resolts, i 3) sortides de camp virtuals d’una regió geològica que permeten proposar activitats prèvies a una pràctica presencial de camp o desenvolupar la pràctica a nivell completament autònom. Per aconseguir aquests objectius, les tasques realitzades són: la compilació i digitalització de la base d'imatges d'exemples naturals d'estructures geològiques de deformació de que disposàvem, junt amb la redacció de material explicatiu (text i figures), la selecció d'un conjunt d'exercicis de la disciplina, i la preparació de dades de camp per a la realització de les sortides virtuals. Paral•lelament, aquest material s'ha estat processant per a la seva disposició en xarxa com un recurs lliure y obert, accessible en una website i domini específics (plataforma REDITEC).

The borehole-fluid effect in electrical resistivity imaging

Fluid that fills boreholes in crosswell electrical resistivity investigations provides the necessary electrical contact between the electrodes and the rock formation but it is also the source of image artifacts in standard inversions that do not account for the effects of the boreholes. The image distortions can be severe for large resistivity contrasts between the rock formation and borehole fluid and for large borehole diameters. We have carried out 3D finite-element modeling using an unstructured-grid approach to quantify the magnitude of borehole effects for different resistivity contrasts, borehole diameters, and electrode configurations. Relatively common resistivity contrasts of 100:1 and borehole diameters of 10 and 20 cm yielded, for a bipole length of 5 m, apparent resistivity underestimates of approximately 12% and 32% when using AB-MN configurations and apparent resistivity overestimates of approximately 24% and 95% when using AM-BN configurations. Effects are generally more severe at shorter bipole spacings. We report the results obtained by either including or ignoring the boreholes in inversions of 3D field data from a test site in Switzerland, where approximately 10,000 crosswell resistivity-tomography measurements were made across six acquisition planes among four boreholes. Inversions of raw data that ignored the boreholes filled with low-resistivity fluid paradoxically produced high-resistivity artifacts around the boreholes. Including correction factors based on the modeling results fora ID model with and without the boreholes did not markedly improve the images. The only satisfactory approach was to use a 3D inversion code that explicitly incorporated the boreholes in the actual inversion. This new approach yielded an electrical resistivity image that was devoid of artifacts around the boreholes and that correlated well with coincident crosswell radar images.

Systematics of Anopheles lanei Galvão and Amaral, a species of the subgenus Nyssorhynchus Blanchard (Diptera: Culicidae)

Anopheles (Nyssorhynchus) lanei Galvão and Amaral is here redescribed using morphological characteristics of adult, male and female, fourth instar larva and pupa. The larva, pupa, and male genitalia are illustrated. Diagnostic morphological characters of adults, male genitalia, fourth instar larva and pupa are provided to distinguish An. lanei from other species of the Argyritarsis section. Species distribution data are based on the published literature records and bionomics data are based on both literature records and field data.