Dissertations / Theses: 'Islands of the Atlantic'

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Walker, Richard James. "The structural evolution of the Faroe Islands, NE Atlantic Margin." Thesis, Durham University, 2010. http://etheses.dur.ac.uk/134/.

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The NE Atlantic margin plays host to numerous basins, developed in phases from the Devono-Carboniferous through to the Cenozoic, which record the build up to plate separation and formation of the North Atlantic Ocean. Existing models for this invoke broadly NW-SE extension within the basins, which are segmented by regional-scale NW-SE trending strike-slip lineaments, which are commonly termed ‘transfer zones’. However, there is a general paucity of information concerning the true kinematics of the so-called transfer zones. In this study, the Palaeogene and later structural evolution of the NE Atlantic margin is investigated using abundant field data collected on the Faroe Islands, and systematic observations that characterise the related deformation structures developed in the Faroe Islands Basalt Group (FIBG). Structures in the Faroe Islands provide evidence for a 6-stage tectonic evolution, here split into 3 broad phases: (1a) E-W to NE-SW extension, accommodated by dip-slip N-S and NW-SE trending faults. Continued NE-SW extension (1b) was then accommodated by the emplacement of a regionally significant NW-SE- and NNE-SSW-oriented dyke swarm. Event 1 affects the majority of the FIBG stratigraphy, resulting in thickness variations, most notably across the Judd, Brynhild and Westray (‘transfer’) fault-zones. Continued magmatism and anticlockwise rotation of the extension vector led to (2a) the emplacement of ENE-WSW and ESE-WNW conjugate dykes, followed by intrusion of the large, saucer-shaped sills on the islands. Their intrusion heralded the onset of N-S crustal extension and was followed by (2b) crustal extrusion involving both E-W shortening and further N-S extension facilitated primarily by slip on ENE-WSW (dextral) and ESE-WNW (sinistral) conjugate strike-slip faults, interlinked with minor NE and SW dipping thrust faults. During the final stages of this event (2c), the regional extension vector rotated into a NW-SE orientation that was accommodated predominantly by slip along NE-SW oriented dextral-oblique-slip faults. Event 2 began towards the end of magmatism associated with the FIBG, and most likely continued through to the onset of oceanic-spreading on the Aegir ridge (ca. 55 Ma). Finally, (3) Event 1 and 2 structures were reactivated as extension and extensional-hybrid features, characterised best by the entrainment of clastic material along fault planes. Relative timings of Event 3 structures suggest they formed during a period of compression and uplift following the formation of a through-going mid-ocean ridge system (i.e. on the Reykjanes, Kolbeinsey and Mohns ridges). The progressive anticlockwise rotation of the extension vector identified here is broadly consistent with the most recent NE Atlantic continental break-up reconstructions. Importantly, this model does not require basin-scale transfer zones during the Palaeogene, suggesting instead that these NW-SE faults formed as normal faults during a pre-cursor margin-parallel extension episode (Event 1) prior to the onset of oceanic spreading in the Faroe-Iceland sector. This study emphasises the importance of carrying out detailed field studies in addition to the more usual regional-scale modelling studies, in order to validate and add further detail to basin kinematic histories. Mineralised syn- to post-magmatic fault sets display a recurring zeolite-calcite-zeolite trend in mineralisation products, which precipitate during successive phases of fault development during each individual event. Fault style and damage zone width appear to be related to the stage of fault development, with early fault/vein meshes linking to form through-going structures with associated damage zones. Dykes and sills are found to form their own fractures, rather than exploiting pre-existing sets. Dyke propagation appears to be buoyancy-driven, with magmatic pressure overcoming the minimum compressive stress. Sills, however, most likely seeded at an interface in the stratigraphy between a weak, more ductile material (i.e. a sedimentary horizon), and a rigid material (i.e. basalt lavas) above. Following this initial development, sill growth and propagation would likely be controlled by viscous dissipation, leading to the complex ramp and flat architecture, with rapid intrusion resulting in upward ramping of the sill. The alternation from fault events, to dyke events and back again corresponds to a switch from faulting with mineralisation along extensional hybrid veins, to magmatic intrusions into extension fractures followed by extensional hybrids (conjugates), and back to extensional and shear hybrid faults (again as conjugates). This alternation reflects variations in the differential regional stress, as well as the magmatic evolution of the margin, and most likely relates to the migration of lithospheric thinning northwestwards across the area, towards the eventual axis of break-up. We find that, in particular, faults in basalts are in many ways comparable to faults formed at shallow crustal depths in carbonate rocks and crystalline basement, most likely reflecting the similarities in their mechanical properties under near-surface pressures and temperatures. The nature and style of the post-magmatic fault infills provides compelling evidence to suggest that subterranean cavities associated with faults were persistent open features within the FIBG. Structures equivalent to these late, clastic-filled faults of the Faroes may occur in other parts of the NE Atlantic margin, particularly along the axes of gentle regional-scale folds that are widely developed in the region. The late fault displacements observed are all well below seismic resolution, and such structures may be more widespread across the region than previously anticipated. Importantly, the probable unsealed nature of the clastic infills makes them potential fluid-migration pathways, both up- and across-faults within the Cenozoic volcanic sequences of the NE Atlantic region.

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2

Driscoll, Paul. "The Channel Islands : an archipelago of the Atlantic Bronze and Early Iron Age." Thesis, University of Bristol, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.573137.

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This thesis examines the Channel Islands in the Atlantic Bronze and Early Iron Age and looks at the way islanders defined their own identity and incorporated material culture into existing and emerging social . - structures. It is a study of interaction and the way prehistoric inhabitants of islands engaged with the world around them. Inter-island and island-mainland relations are explored and chronologies for Channel Island later prehistory are refined. In particular, it is proposed that the Early Bronze Age in the Channel Islands does not begin until after 1750/1700 BC, when a series of events are recognised in the archaeological and palaeoenvironmental records. Tumuli are introduced along with specific material culture related to second series barrows of Armorica, contemporary (potentially) with the first bronze hoard. Long term deforestation begins, alongside a rise in the pastoral economy and selective pockets of arable farming. Changing sea levels and improvements in seafaring technology opened up the sea as a mechanism for interaction and enabled islanders to undertake voyages to other places. Such voyages were a way of maintaining alliances, trading goods and gaining knowledge that led to the successful reproduction of Channel Island society. Certainly after 1300 BC the islands become more deeply involved in Atlantic and cross-channel exchange networks as demonstrated by the St Helier Gold Torque and the deposition of bronze hoards of excessive size (three are over 200 pieces each). These hoards also show a divergence from neighbouring French zones through the accumulation of metalwork from a wider geographical area. The ceramic assemblages for the islands show a clear parallel with NW France and in some cases southern Britain. Long term perspectives on the ways islanders impacted on their world are also explored and it is suggested that the intensive process of deforestation that begins to occur in the Early Bronze Age was tempered by sustainable management of the landscape, through a pastoral economy and selective arable farming. This was replaced in the Early Iron Age by aggressive burning strategies and the rapid clearance of land for arable purposes. These activities had a long lasting impact, removing the ancient woodland that had once dominated the prehistoric islands and creating a landscape that was irreversibly altered.

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Mairs, Kerry-Anne. "Islands and human impact : under what circumstances do people put unsustainable demands on island environments? : evidence from the North Atlantic." Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/24887.

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Firstly, hypothesis-led research focussed on the islands of Suouroy and Sandoy in the Faroe Islands. Secondly, comparative led interpretations focussed on the importance of the Faroes within the wider Norse North Atlantic. A landscape-scaled, historical ecology approach incorporating original data from landscape mapping, stratigraphic profile analyses, archaeological survey and semi-structured interviews was developed. Maps were produced of soil degradation and geomorphic features in the Hov catchment and north Sandoy, 226 archaeological structures on two walk-over archaeological surveys were mapped, interviews were made with four Sandoy residents, 86 stratigraphic sections were recorded and a chronological framework was provided by 54 radiocarbon dates. The following interpretations were made: Two significant environmental thresholds have influenced development of the mid-late Holocene Faroe Islands landscape. The most significant occurred prior to human settlement between c.2900-2300 cal yrs BP as a result of deteriorating climate in the North Atlantic. The second is less distinct and occurred as two phases, c.60-400AD and c.400-650 AD. Human impacts through the introduction of livestock may have caused environmental changes at these times but there is no firm evidence of human occupation in the Faroes prior to the sixth century. Human impact in the Faroes has been overshadowed by earlier climatically induced impacts. Human impact in the Faroes is in part limited because dynamic elements of the landscape were already established prior to landnám, because the landscape was open and deforested at the time of the settlement and because erosion was limited by the diversification of subsistence strategies. In Iceland, analyses of 98 sediment stratigraphies incorporating 1127 tephras and 769 calendar dates across 10 landholdings were compared with the Faroes data. It is concluded that Iceland may have suffered more severe environmental degradation because its biota and soils were sensitive to human impact and because the Norse subsistence strategy focussed principally on pastoral agriculture.

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Jones, Jennifer Rose. "Land and sea : understanding diet and economies through time in the North Atlantic Islands." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/57650/.

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This thesis explores changes in dietary and economic behaviour through time in the North Atlantic Islands of Scotland, from the Mesolithic-Neolithic transition through to the Norse period. Traditional zooarchaeological techniques are used alongside human and faunal stable isotope analysis to explore past diet of humans and animals. The challenges of integrating these two different datasets and methodologies for enhancing interpretations of these lines of evidence are explored. A suite of faunal isotopic values though time were generated to characterise animal diets, past husbandry strategies, to provide a baseline to interpret human values, and to understand temporal and geographical variations in isotopic values. Faunal isotopic values indicate that shore front resources were used by past populations, and highlight temporal and geographical differences in management practices and foddering strategies. Results demonstrated that marine species were not a major aspect of diet in the Neolithic, supporting Schulting and Richards (2002a). In the Bronze Age there is an increase in the quantity of fish bones present within the faunal assemblages in the Western Isles, however they were not being consumed in sufficient quantities to affect the human bone collagen isotopic values. During the Iron Age there is a further increase in the quantity of fish bones present in assemblages in the Western Isles, and evidence of fish consumption in human and pigs. In contrast evidence of marine food consumption in Iron Age Orkney is minimal, indicating divergent dietary and economic practices in place between these regions. During the Norse period fish bones account for high proportions of the zooarchaeological assemblages in both Orkney and the Western Isles, with different species being exploited. Finally comparisons are drawn with island and inland sites in Britain and Europe, exploring how far these dietary and economic practices observed are influenced by localised environmental conditions, and wider social factors.

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Francisco, Flavio de Oliveira. "Estrutura e diversidade genética de populações insulares e continentais de abelhas da Mata Atlântica." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/41/41131/tde-22012013-150602/.

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Durante muito tempo as ilhas vêm sendo fundamentais para pesquisa em ecologia e biologia evolutiva. Esses estudos tornaram possível a elaboração de importantes teorias nesses campos e que puderam ser extrapoladas para diversos outros ambientes. O aumento dos desmatamentos e da fragmentação de habitats tem levado ao isolamento dos organismos em \"ilhas\" dentro do continente. A perda de diversidade em fragmentos é uma situação preocupante. Populações restritas a ilhas ou fragmentos possuem maior probabilidade de extinção. As abelhas possuem um papel fundamental nos ecossistemas e por isso a extinção de uma população terá impacto nos outros níveis tróficos. Em virtude disso, o objetivo desse trabalho foi testar a hipótese de que populações das abelhas Tetragonisca angustula e Bombus morio de ilhas com mais de 100 ha localizados nos estados de Santa Catarina (SC), Paraná (PR), São Paulo (SP) e Rio de Janeiro (RJ), e populações continentais em áreas próximas a remanescentes de Mata Atlântica nos estados de Minas Gerais (MG), PR, RJ, SC e SP possuem baixa diversidade genética e, por isso, estariam mais propensas à extinção. Nossos resultados mostraram que a espécie T. angustula apresenta alta filopatria de rainhas e baixa diversidade genética mitocondrial. Por outro lado, os microssatélites mostraram menor estruturação e alta/moderada diversidade genética, indicando que os machos são o sexo dispersor. Para a espécie B. morio, a diversidade genética observada para ambos os marcadores foi alta, com exceção de duas populações. As fêmeas também apresentaram maior estruturação populacional, enquanto que para os machos essa estruturação praticamente não existiu. Portanto, as populações das espécies T. angustula e B. morio não apresentam inclinação à extinção. A sobrevivência em ambientes urbanos e a grande capacidade de migração dos machos parecem ser fatores fundamentais para isso. Além disso, essas características parecem ser as responsáveis pelo não isolamento genético entre muitas das populações geograficamente isoladas
Islands have been key research fields on the ecology and evolutionary biology for a long time. The study of their biota has made possible the development of important theories that could be extrapolated to other environments. The increase in deforestation and habitat fragmentation has led to isolation of the organisms in \"islands\" within the continent. Loss of diversity in fragments is a concern, because nowadays many species only exist in fragments. Populations restricted to islands or fragments have higher probability of extinction. Bees have a key role in ecosystems and the extinction of their populations will impact other trophic levels. The aim of this study was to test the hypothesis that populations of two bee species, Tetragonisca angustula and Bombus morio, in islands with more than 100 ha located in the states of Santa Catarina (SC), Paraná (PR), São Paulo (SP) and Rio de Janeiro (RJ), and mainland populations in areas near the Atlantic Forest remnants in the states of Minas Gerais (MG), PR, RJ, SC and SP have low genetic diversity and therefore would be more prone to extinction. Our results to T. angustula showed low mitochondrial genetic diversity which can be associated to queen philopatry behavior. Moreover, microsatellites showed lower structure and moderate/high genetic diversity, indicating a greater dispersion by males. The genetic diversity observed for B. morio for both markers was high, excepting two populations. Females also had higher population structure than detected for males. Therefore, most of T. angustula and B. morio populations are not prone to extinction, mainly because of their capability to survive in urban environments and high male migration. Therefore, these characteristics seem to be responsible for allowing many of the geographically isolated populations do not present genetic isolation

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Ba, Palmqvist Penda. "Crossing the Atlantic Ocean to look elsewhere – a humanitarian crisis on the Canary Islands 2020-2021." Thesis, Uppsala universitet, Teologiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-454049.

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During 2020 and 2021, a migration crisis has been developing on the Canary Islands in Spain. Large numbers of African migrants have made the dangerous journey from West Africa to the Canary Islands, risking their lives on the Atlantic Sea. Humanitarian aid organizations, like the Spanish Red Cross, are working intensively to handle the humanitarian needs of the migrants on land and on sea. The purpose of this thesis is to analyze why the migration crisis on the Canary Islands occurs. The migrants originate from different African countries with different reasons why they choose to migrate. In some countries, there are ongoing wars and conflicts, like in Mali. In other countries, people migrate because of poverty, climate change and displacement to seek a better life. This thesis will answer why Senegalese people choose to migrate on this dangerous route on the Atlantic Sea. The study is based on interviews with three Senegalese migrants and two representatives of humanitarian aid organizations. The analysis has been made from different migration theories. It shows that an important reason why the Senegalese migrants choose to migrate is that it is no longer possible to make a living by fishing and provide for their families. This works as an important push factor to migrate. Another push factor is the lack of trust in the Senegalese government. An important pull factor are the success stories from migrants who have made the journey through the Canary Islands. According to the aspiration and capabilities theory, the aspirations to migrate increase when a country goes from being very poor to richer. This is because the knowledge about the surrounding world and the opportunities increase. The study shows that migrants are well aware of the risks when crossing the Atlantic Sea, but they choose the route because there are almost no legal ways for them to migrate.

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Paterson, Ian. "Molecular genetic (RAPD) analysis of Leach's storm petrels (Oceanodroma leucorhoa) from three breeding islands in Atlantic Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq22034.pdf.

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8

Bending, Joanna Mary. "The economy of the Norse settlement of the North Atlantic Islands and its environmental impact : an archaeobotanical assessment." Thesis, University of Sheffield, 2007. http://etheses.whiterose.ac.uk/12794/.

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The objective of the archaeobotanical research presented here is to assess the introduction of Norse agricultural economies to Iceland and the-Faroe Islands during the 9`h and 10`h centuries AD, and the impact of the settlers' behaviour on plant communities until AD 1500. The major themes concern the presettlement landscape and environmental conditions, the impact of human activity on these landscapes, the non-native plant taxa introduced, the short and long-term change in local environments, and the adaptation of the Norse economic system and living conditions to the new environments. These themes are approached through the comparison of two datasets, one based on material from monoliths taken from peat sequences ('off-site' samples) and the other on the analysis of samples of deposits from archaeological sites ('on-site' samples). Pre-settlement conditions consisted of a mosaic of acidic, nutrient-poor wetland, grassland or heath in the valley bottoms. Woodland cover was dominated by Betula and Salix, which was denser in Iceland than in the Faroe Islands. PreNorse changes in the Faroese landscape are evident, which relate to an increasing body of material that has been interpreted as evidence for pre-Norse settlement. At the time of landnäm, there is evidence for woodland clearance, although this does not happen uniformly across the landscape. Clearance can be interpreted as a change in the landscape due to the introduction of an economy based on animal grazing, and the collection of wood and twigs for fuel and fodder. Crop and wild plant taxa were introduced, although the range of plants is not as broad as in Scandinavia and the British Isles. Fuel collection and building construction were determined by the lack of suitable wood sources in the newly settled areas. In the longer term, there is evidence for soil enrichment in the areas around settlements, continuing deforestation and erosion.

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Niedermeier, Nicole. "Experimental determination of the mass deposition flux of mineral dust at the Cape Verde Islands." Doctoral thesis, Universitätsbibliothek Leipzig, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-141260.

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Der Eintrag von Mineralstaub in den Ozean geschieht entweder durch trockene oder durch nasse Deposition. Dies ist ein wichtiger Prozess um ozeanische Organismen wie Phytoplankton mit Nährstoffen (z.B. Nitrat, Phosphat oder Eisen) zu versorgen. Viele Modelle befassen sich mit der Simulation von Depositionsflüssen von Mineralstaub in den Ozean. Messungen von Massendepositionsflüssen von Mineralstaub sind hingegen selten. Daher ist es von großer Notwendigkeit, diese Messungen durchzuführen um die vielen Modelle zu validieren und den Mineralstaubzyklus besser zu verstehen. Innerhalb des SOPRAN Projektes (Surface Ocean PRocesses in the ANthropocene) wird der Materialtransport zwischen der Atmosphäre und dem Ozean untersucht. Die Messungen dafür wurden auf den Kapverdischen Inseln durchgeführt, über welchen der Saharastaub durch die Passatwindzirkulation vorwiegend transportiert wird. Im Rahmen dieser Arbeit werden in-situ Messungen von trockener Deposition von Mineralstaub in den Ozean präsentiert. Verschiedene Methoden wurden auf ihre Anwendbarkeit getestet und deren Ergebnisse miteinander verglichen. Alle Messergebnisse liegen im Bereich der Messunsicherheiten, wodurch ein Satz qualitätsgesicherter Daten aufgebaut werden konnte. Diese Daten wurden mit den Ergebnissen eines regionalen Chemie-Transport Modells verglichen. Modellierte Massendepositionsflüsse von Mineralstaub waren manchmal doppelt so hoch wie gemessene. Die größte Unsicherheit der Modelle liegt in der Emission des Mineralstaubs, die im Transport und der Deposition fortgesetzt wird. Weitere Unterschiede entstehen durch den Vergleich von Punktmessungen mit einer Gitterzelle, wenn der Staub nicht gleichmäßig über die Gitterzelle verteilt ist. Zusammenfassend wurden Massendepositionsmessungen von Mineralstaub erfolgreich mit verschiedenen Methoden durchgeführt. Mit den Erfahrungen aus dieser Studie ist es nun möglich, Langzeitmessungen von Mineralstaubdeposition in den Ozean erstellen. Diese Daten können von Atmosphärenmodellierern für ihre Modellvalidierung genutzt werden. Anwender von Ozeanmodellen und SOPRAN Partner werden diese Ergebnisse nutzen um z.B. die ozeanische Reaktion auf den Mineralstaubeintrag zu untersuchen
The input of mineral dust to the oceans, via dry or wet deposition, is an important process, because the entrainment of nutrients (e.g., Nitrate, Phosphor and Iron) is essential for oceanic life such as phytoplankton. A lot of effort has been done to model the dust deposition fluxes to the ocean. However, field measurements concerning the deposition flux are sparse. Therefore, those measurements are needed in order to verify the huge amount of model outputs and to better understand the mineral dust cycle. Within the project SOPRAN (Surface Ocean PRocesses in the ANthropocene), the influence of material exchange between the atmosphere and the ocean is investigated. Measurements were carried out at the Cape Verde Islands in the direct outflow of the Saharan Desert. This study presents the first in-situ measurements of the dry mass deposition flux of mineral dust to the ocean. The applicability of different methods was tested and the results were compared to each other. The results of the measured data were comparable and a set of quality assured data could be built up. Those results were compared to the output of a regional chemistry- transport model. The modeled mass deposition flux was sometimes double as high as the measured one. The main uncertainty of the models is the emission of mineral dust at the source region, proceeding in the transport and emission of mineral dust. Furthermore, comparing single point measurements with outputs of a grid cell leads to differences in deposition fluxes by an inhomogeneous distribution of the mineral dust layer. Summarizing, the measurements of the mass deposition flux of mineral dust could be performed successfully with several methods. With the expertise of this study, long-term observations of the mineral dust deposition to the ocean can now be established. These data can be used by atmosphere modelers to validate their models. Ocean modelers and partners of the SOPRAN project will use these data to investigate e.g., the biological response of the ocean to mineral dust entrainment

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Meunier, Renee Monique. "War in the South Atlantic : the mythology of the Monroe Doctrine and the Western Hemisphere idea : the Falkland Islands : a case study /." View abstract, 1999. http://library.ctstateu.edu/ccsu%5Ftheses/1535.html.

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Thesis (M.S.)--Central Connecticut State University, 1999.
Thesis advisor: Dr. Alfred C. Richard Jr. " ... in partial fulfillment of the requirements for the degree of Master of Science International Studies." Includes bibliographical references (leaves 130-137).

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11

Brown, Judith. "Ecology and life history of a deepwater notothenid, Dissostichus eleginoides Smitt 1989, around the Falkland Islands, SW Atlantic Ocean." Thesis, University of Aberdeen, 2011. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=165537.

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The aim of this research was to gain a better understanding of the ecology and life history of the deepwater notothenid, Dissostichus eleginoides, on the Patagonian Shelf. Archival tagging revealed strong site fidelity of adult toothfish with the majority of fish remaining within 50km of release. Furthermore depth data revealed three behavioural patterns showing feeding, seasonal and spawning activities. The trophic ecology of five notothenioids was studied, examining resource utilisation and niche separation on the Falkland’s shelf. Spatial, ontogenic and seasonal variations in the parasite fauna for juvenile D. eleginoides are described and potential species for use as biological tags to study toothfish population structure are suggested. Validated age readings gave maximum estimated ages of 35 (L = 214.3cm) and 26 years (L = 126.3cm) for females and males respectively and reasons for this sexual dimorphism are discussed. Comparisons of otolith transition zones and growth rates from different regions shows toothfish have adapted their life history traits dependant on their environmental and hydrological surroundings, with populations in warmer areas growing quicker than those in cooler waters. Reproduction in toothfish is discontinuous and group synchronous and final spawning was found to occur in batches. Toothfish predominantly spawn only in one region around the Falklands, on the Burdwood Bank, mainly during July/August. Evidence of skipped spawning was identified indicating that not all fish spawn annually and this aspect is discussed in terms of body condition, periodic strong recruitment and the lack of large scale migrations of adult toothfish. Toothfish around the Falklands have a higher fecundity compared to other regions, a potential adaption to living north of the polar front. This new information on age, growth, reproduction and movements of toothfish, combined with its role in the Patagonian shelf and slope ecosystems, is vital for accurate stock assessment and hence sustainable fisheries management.

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Passey, Simon Richard. "The volcanic and sedimentary evolution of the Faeroe plateau lava group, Faeroe Islands and Faeroe-Shetland Basin, NE Atlantic." Thesis, University of Glasgow, 2004. http://theses.gla.ac.uk/3504/.

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Geochemical analysis of the volcanic interval in Well 214/4-1, Faeroe-Shetland Basin, has enabled a correlation to the Lower Basalt Formation of the Faeroe Islands, ca. 240 km to the W. The volcanic interval consists of a ca. 450 m thick sequence of hyaloclastites, which are overlain by a ca. 50 m thick subaerial lava sequence. This volcanic interval is interpreted to have formed at a palaeoshoreline environment, where subaerial lavas flowed from the land surface into a substantial body of water at least 450 m deep (i.e. the Faeroe-Shetland Basin at that time), resulting in the quenching and fragmentation of magma to product the hyaloclastities. Well 214/4-1 is <50 km to the SE of the Faeroe-Shetland Escarpment, which has previously been interpreted as a hyaloclastite delta, thus implying that there a number of unrecognised hyaloclastite units within the Faeroe-Shetland Basin and that the coastline was steadily encroaching W/NW, towards the Faeroe Islands during the volcanic interval. The overlying ca. 10 m thick Coal-bearing Formation (CBF) represents a significant hiatus in the volcanic activity at the end of LBF times. Erosion and subsidence of the lava field led to the development of an expansive lacustrine environment, which resulted in the accumulation of plant material and associated detritus and chemical sediments, mainly ironstones, and the formation of mineable coal seams. Petrographic and geochemical analysis of siderite spherules within the ironstone beds from two localities on Suðuroy have helped to define margin- and centre of-lake environments, at least 10 km apart. Contemporaneous fluviatile lithologies in West Suðuroy are composed of reworked palagonitised tephra, basalt lava clasts and plant material.

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Heller, Erin Leigh. "Factors affecting Western Atlantic red knots (Calidris canutus rufa) and their prey during spring migration on Virginia's barrier islands." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/99099.

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Understanding factors that influence a species' distribution and abundance across their annual cycle is needed for range-wide conservation planning. Every year during spring migration, thousands of federally threatened (U.S.A.) and endangered (Canada) migratory Western Atlantic red knots (Calidris canutus rufa, 'red knot') use Virginia's barrier islands as stopover habitat to regain the fat required to continue flights to breeding grounds. Because the red knot completes one of the longest avian migrations in the world and relies on variable prey resources at its stopover grounds, the red knot exemplifies the challenges faced by long-distance migrant shorebirds. These challenges may be exacerbated by climate change, as long-distance migrants may be unable to adapt quickly to changing prey ranges and abundances, resulting in spatial and temporal mismatches between predators and prey. More specifically, as climate change causes ocean temperatures near Virginia's barrier islands to rise, organisms that live within the intertidal zone, like blue mussels (Mytilus edulis), are experiencing range shifts. Here, we 1) confirmed what prey red knots select in Virginia, 2) addressed the factors that affect red knot site selection, red knot flock size, and prey abundances across Virginia's barrier island intertidal shoreline during 2007 – 2018, and 3) predicted the origin of juvenile blue mussels, a key prey resource for red knots in Virginia. To determine which prey are most available to red knots in Virginia, we collected sand and peat substrate core samples from Virginia's ocean intertidal zone and counted the number of prey in each sample. We compared these prey availability data to prey DNA data obtained from fecal DNA metabarcoding analyses on red knot feces (n = 100) collected on peat and sand substrates between 2017 – 2019. Red knots consumed prey from Orders Veneroida (clams), Mytiloida (mussels), Diptera (flies), and Amphipoda/Calanoida (crustaceans). While crustaceans were the most abundant prey on both sand (70.80% of total prey counted) and peat (74.88%) substrates, red knots selected crustaceans less than expected given their availability. Red knots selected clams and mussels, supporting their status as bivalve specialists in Virginia. After determining which prey red knots consumed and selected in Virginia, we predicted the number of red knots using Virginia's barrier island stopover during their migratory stopover (May 14 – 27, 2007 – 2018) annually. We used confirmed prey, tide, distance to known roosts, and red knot winter counts from Tierra del Fuego to inform zero-inflated negative binomial mixed-effects regression models of red knot site selection and flock size in Virginia. We also used generalized linear mixed-effects regression models to determine how climatic and geomorphological factors affected prey abundances. Modeled red knot peak counts were highest in 2012 (11,644) and lowest in 2014 (2,792; x̄ = 7,055, SD = 2,841); the trend over time was variable but there was no evidence of a linear increase or decrease. Red knots selected foraging locations with more prey, though red knot flock size did not consistently relate to prey abundance. Tide, substrate, and water temperature affected prey availability. While different prey responded to these covariates in variable ways, prey generally were most abundant on peat banks at low tide. Given the importance of blue mussels in the red knot's diet and distribution in Virginia, if the blue mussel's range continues to contract northward, red knots could be faced with additional fat replenishment challenges. We analyzed the variation in blue mussels from 2010 – 2018 by collecting core samples on peat banks in Virginia and counting the number of blue mussels in the cores. To approximate the origin of Virginia's juvenile blue mussels and determine how continued ocean temperature warming may further affect the blue mussel's range contraction, we conducted oxygen stable isotope (δ18Oc) analyses on 74 blue mussel shell umbos (the first portion of the shell precipitated) and shell edges (the most recently precipitated shell) to compare and predict where different portions of the shell were formed. We compared blue mussel shell compositions to δ18Oc calculated in equilibrium with regional ocean water using recorded δ18Ow data and sea surface temperature data from ocean buoys between New Hampshire and Virginia. Blue mussel abundance/core sample declined over the duration of our study (Spearman's rank correlation coefficient: ρ(rho) = -0.31, p < 0.001), with the highest abundance in 2010 (x̄ blue mussels/core sample = 537.88, SE = 85.85) and lowest in 2016 (x̄ = 34.08 blue mussels/core sample, SE = 6.96). Blue mussel umbos (x̄ δ18Oc = -0.23‰, SE = 0.12) contained more positive δ18Oc than shell edges (x̄ δ18Oc = -0.53‰, SE = 0.20), suggesting that Virginia's blue mussels originated from ocean populations in more saline and/or colder water than that within Virginia's intertidal zone. Blue mussel umbo δ18Oc were not different than δ18Oc calculated in equilibrium with regional ocean water off the Virginia and Delaware coasts, suggesting that Virginia's blue mussels originated in ocean waters between Delaware and Virginia; however, they may have originated in waters as far north as New York in some years, potentially decreasing the risk of blue mussels being completely extirpated from Virginia in the near future. While red knots currently use spring migratory stopovers across the United States' Atlantic Coast, from Florida to New Jersey, the largest spring concentrations of knots are confined to the Delaware Bay and Virginia's barrier islands. Because these stopover grounds support large proportions of the red knot's migratory population, any changes in the factors that affect red knots at these stopover sites could have lasting implications for red knots. The blue mussel's range contraction and decline over time in Virginia, for example, is concerning from a conservation perspective. Red knots require easily accessible and abundant prey resources to efficiently replenish fat-stores needed for continued migration and breeding. Additionally, because red knots breed within a narrow period, any delays on stopover grounds could prevent red knots from breeding, even if they survive migration. Our research demonstrates that red knots use prey abundance as a determinant when selecting foraging locations, and that peat banks, while only sporadically available across the barrier islands at mid- to low-tides, contain higher prey abundances than sand. Thus, to continue maximizing the availability of prey in Virginia, measures should continue to be taken to allow natural island migration processes that encourage the presence of both sand and peat substrates. Beach nourishment and stabilization projects are often used on coastal beaches to prevent shoreline erosion; however, such actions prevent the formation of peat banks by blocking island migration processes. A reduction in peat banks could decrease the abundance of prey available to red knots, making weight gain during the critical stopover period more challenging for red knots. Additionally, beach nourishment through sand replenishment buries invertebrate prey, potentially causing mass prey mortality and reducing shorebirds' ability to access deeply buried prey. To prevent the loss of important peat banks on these islands, and to prevent disrupting predator-prey interactions, managers should continue their ongoing focus on allowing natural processes to occur on Virginia's barrier islands.
Doctor of Philosophy
Red knots (Calidris canutus rufa) are imperiled shorebirds that migrate thousands of kilometers each year from wintering grounds as far south as Argentina to breeding grounds in the Canadian Arctic. To migrate such long distances, red knots use stopover habitat, like Virginia's barrier islands, to regain the fat required to continue flights to breeding grounds. Climate change is causing the ranges of important red knot prey, such as blue mussels (Mytilus edulis), to shift. Red knots may be unable to quickly adapt to changes in prey abundances on stopover grounds, making it more challenging for them to gain the weight required for successful migration and breeding. Thus, understanding the factors that may affect red knots in Virginia are important for successful management of this shorebird. Here, we determined what prey red knots consume in Virginia, addressed the factors that affect red knots in Virginia, and predicted the origin of blue mussels, an important prey resource for red knots in Virginia. We collected sand and peat substrate samples from Virginia's ocean intertidal zone to determine what prey were available to red knots and collected red knot feces to determine what prey red knots consume. Red knots consumed clams, mussels, fly larvae, and crustaceans in Virginia and showed preference for clams and mussels over the more abundant crustaceans. Red knots selected foraging locations that had higher prey abundances than unused sites. The relationship between red knots and prey was affected by the tidal cycle, with the highest abundance of prey available and most birds foraging at low tide when peat banks were exposed. After confirming that red knots preferentially consume blue mussels, which is experiencing a northward range contraction due to increasing ocean temperatures, we analyzed how blue mussel numbers have changed over time in Virginia. Blue mussel numbers declined over the duration of our study. We also analyzed blue mussel shells to help determine where the blue mussels were spawned, as shells contain environmental clues that relate to the conditions within which the shell forms. The juvenile blue mussels red knots consumed on Virginia's peat banks likely originated in ocean waters between Delaware and Virginia, but potentially in waters as far north as New York, possibly using ocean currents to travel to Virginia's intertidal zone. Because migratory stopovers, like Virginia's barrier islands, support a large percentage of the total red knot migratory population, any changes in factors that affect red knots during their spring stopover, like prey availability, may negatively affect red knots. Because red knots need to quickly consume large quantities of prey to gain the weight needed for continued migration and breeding, managers should continue to prevent factors that negatively affect prey in Virginia. For example, we found that peat banks support high quantities of red knot prey; thus, continuing to ensure that peat banks are able to form on the islands is paramount. However, peat banks form through shoreline erosion and overwash, two natural processes which are often portrayed negatively. Beach nourishment and stabilization projects are commonly used in other coastal areas to prevent shoreline erosion and overwash along coastal beaches. If Virginia's barrier island beaches are nourished, natural processes like shoreline erosion may be less likely to occur. The absence of shoreline erosion on Virginia's barrier islands would preclude the formation of peat banks, likely decreasing prey availability for red knots. Beach nourishment also buries invertebrate prey, as sand is deposited along the beaches' intertidal zone. The disturbance caused by nourishment combined with the reduction in prey caused by it could negatively affect red knots in Virginia. Managers should continue to protect both peat and sand substrates by further allowing natural processes, like shoreline erosion, to occur on Virginia's barrier islands.

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14

Muzaffar, Sabir Bin. "Ectoparasites of auks (Alcidae) at the Gannet Islands, Labrador, diversity, ecology and host-parasite interactions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0015/MQ55531.pdf.

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15

Parker, Wesley G. "Holocene Climate Change in the Subtropical Eastern North Atlantic: Integrating High-resolution Sclerochronology and Shell Midden Archaeology in the Canary Islands, Spain." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1583155239092873.

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16

Ahronson, Kristján. "Claiming a wilderness : Atlantic Gaels and the island Norse." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/15812.

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This thesis reviews archaeological material, medieval literature, place-names and palaeoenvironmental data cited in explorations of the early Viking Age North Atlantic area, and proposes a reassessment of chronology for the earliest settlement of Iceland. After analysing previous scholarship and discussing the problems inherent in study of early North Atlantic settlement, it is suggested that a multi-disciplinary approach is needed and can be articulated (by drawing upon Karl Popper’s ideas) to foster a fruitful conversation between disciplines. This methodology for engaging with multi-disciplinary materials is then presented. Three sections follow, tackling in turn three areas of Viking Age scholarship that have caused difficulty and frustration in the past: the toponymy of Hebridean Pap-islands (Chapter Three); the chronology of carve construction, occupation and human-environmental interactions at Seljaland in southern Iceland (Chapters Four, Five, Six, and Seven); and the İrland et mikla tradition of medieval literature, including discussion of the views of the largely forgotten nineteenth-century scholar Eugène Beauvois (Chapter Eight). Couched in a Popperian methodology, the new archaeological and palaeoenvironmental research that forms the bulk of the thesis is integrated with small-scale studies of place-names and medieval literature. Tephronchronology plays a large part in the Seljaland section. Chapter Six, for instance, introduces the tephra contours technique for study of past environments. The thesis concludes with a new proposal for the first settlement of Iceland and its connections to Atlantic Scotland, arrived at by considering the archaeological and tephra deposits at Seljaland, in conjunction with art-historical, toponymic and literary material. The thesis proposes that southern Iceland’s Seljaland caves were built c. AD 800 – earlier than the traditional Norse foundation of settlement on the island – and that cross sculpture in these caves suggests a connection with Gaelic monasticism found across the Scottish islands in this period.

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17

Bruguier, Nigel John. "Crustal structure of the Mid-Atlantic Ridge near Ascension Island." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624243.

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18

Hansen, Jógvan. "Petrogenetic evolution, geometries and intrusive styles of the early Cenozoic saucer-shaped sills of the Faroe Islands." Thesis, Durham University, 2011. http://etheses.dur.ac.uk/3631/.

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Geometries of sills intruded into the lava pile of the Faroe Island Basalt Group (FIBG), which were targeted in this study, were mostly recorded by conventional mapping methods where measured distances and positions were plotted onto accurate topographic maps aided by the use of high-quality photos of relevant outcrops. These data were subsequently used to manually plot 2D profiles along selected tracks and to produce electronic 3D maps using ArcGIS software. The general geometries of the investigated sills, measured at lateral scales ranging from a few metres to a few kilometres and at vertical scales ranging from a few metres to a few hundred metres, differ somewhat from typical sill geometries reported previously for sills intruded into sedimentary successions. The ubiquitous saucer-shapes of the sills from this study, which generally curve upwards in a gradual manner from inner sub-horizontal sections to steeper outer margins, contrast with the common angular transitions from inner sub-horizontal to outer steeper sections of sills reported from sedimentary host-rocks. In this thesis we explore possible alternatives to already existing theories on sill emplacement in sedimentary successions. Major and trace element compositions for samples representing most of the sills exposed in the Faroe Islands have been determined by means of XRF and ICP-MS analyses. Geochemically most of these sills can be grouped into two main categories characterised either by high or by low TiO2 contents. Different sorts/types of metasomatism of source rocks to high-TiO2 versus low-TiO2 sills are indicated by different Nb and Ta anomalies. Modelling by means of REE and other trace elements suggest that much of the compositional differences between these two main categories can be explained by various degrees of partial melting of broadly similar mantle sources. Additional fractionation and accumulation of plagioclase modified some of the melts that gave rise to the actual sills. The initial partial melting event probably occurred at depths slightly shallower than the lower limit of the garnet stability field at ~85 km while plagioclase crystallisation/accumulation most likely occurred at depths shallower than ~18 km. Isotopic compositions may point to very slight contamination of some sills with crustal material.

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19

Ewens, Vicki J. "An odontological study of ovicaprine herding strategies in the North Atlantic islands. The potential of dental enamel defects for identifying secondary product utilisation in an archaeological context." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5106.

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Abstract: Recent debate concerning the suitability of mortality profile analysis for identifying secondary product utilisation within archaeozoological assemblages has prompted the search for alternative methodologies. This research explores the potential of using weaning age to provide insight into herding strategies in ovicaprines, determined through the prevalence of developmental enamel defects. A histological methodology was developed, adapted to the specific nature of sheep molars through an understanding of formation processes and enamel structures. This established a relationship between weaning and developmental defects in modern sheep, revealed as distinct patterns in defect distribution within the enamel. Based on historical/archaeological data a weaning age model was developed for the North Atlantic region by which herding strategies could be recognised, specifically: mixed milk/meat subsistence, with an emphasis on milk (0-2 months) or on meat (2-4 months), and the optimisation of meat and/or wool (4-6 months). This methodology was then tested on archaeological material to interpret husbandry at Iron Age and Norse/Viking period sites. The results of this analysis showed that interpretations were in general agreement with those of mortality profile and correspondence analysis conducted as a methodological comparative. Some disparity, however, highlighted the ability of this new technique to provide more sensitivity in cases of mixed subsistence systems, possibly identifying the economic focus of husbandry, or where mortality profiles are confused. It was concluded that the study of weaning age has potential to provide valuable insight into ovicaprine husbandry in archaeological contexts, adding to the understanding of faunal assemblages, especially when supported with other evidence.
Recent debate concerning the suitability of mortality profile analysis for identifying secondary product utilisation within archaeozoological assemblages has prompted the search for alternative methodologies. This research explores the potential of using weaning age to provide insight into herding strategies in ovicaprines, determined through the prevalence of developmental enamel defects. A histological methodology was developed, adapted to the specific nature of sheep molars through an understanding of formation processes and enamel structures. This established a relationship between weaning and developmental defects in modern sheep, revealed as distinct patterns in defect distribution within the enamel. Based on historical/archaeological data a weaning age model was developed for the North Atlantic region by which herding strategies could be recognised, specifically: mixed milk/meat subsistence, with an emphasis on milk (0-2 months) or on meat (2-4 months), and the optimisation of meat and/or wool (4-6 months). This methodology was then tested on archaeological material to interpret husbandry at Iron Age and Norse/Viking period sites. The results of this analysis showed that interpretations were in general agreement with those of mortality profile and correspondence analysis conducted as a methodological comparative. Some disparity, however, highlighted the ability of this new technique to provide more sensitivity in cases of mixed subsistence systems, possibly identifying the economic focus of husbandry, or where mortality profiles are confused. It was concluded that the study of weaning age has potential to provide valuable insight into ovicaprine husbandry in archaeological contexts, adding to the understanding of faunal assemblages, especially when supported with other evidence.

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20

CORREIA, Érika Pinho. "Migração vertical do microzooplâncton do Arquipélago de São Pedro e São Paulo." Universidade Federal de Pernambuco, 2014. https://repositorio.ufpe.br/handle/123456789/18920.

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Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-05-25T17:32:09Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Correia, 2014. Migração vertical do microzooplâncton do Arqu.pdf: 826813 bytes, checksum: 00687ea39607e8dbd933fd417ff647dc (MD5)
Made available in DSpace on 2017-05-25T17:32:09Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Correia, 2014. Migração vertical do microzooplâncton do Arqu.pdf: 826813 bytes, checksum: 00687ea39607e8dbd933fd417ff647dc (MD5) Previous issue date: 2014
A presente dissertação é composta por dois manuscritos. O primeiro foi elaborado com o intuito de responder ao objetivo principal da dissertação: caracterizar a migração vertical do microzooplâncton do Arquipélago de São Pedro e São Paulo (ASPSP). A partir das amostras analisadas, ainda foi possível obter um manuscrito adicional, registrando a primeira ocorrência de Aetideus australis para o Brasil e Aetideus giesbrechti para o ASPSP. Para isto, foram realizadas coletas diurnas e noturnas em três campanhas (C1: junho de 2010; C2: setembro de 2011; C3: outubro de 2011), em duas estações fixas, uma a leste (E1) e outra a oeste (E2) do ASPSP. Foram feitos arrastos verticais com rede de plâncton com sistema de fechamento tipo Nansen e malha com abertura de 64 μm, em cinco camadas pré-determinadas de 20 metros, até 100 m de profundidade (L1: 0-20 m, L2: 20-40 m, L3: 40-60 m, L4: 60-80 m e L5: 80-100 m). Adicionalmente, para caracterizar a estrutura termohalina, foram obtidos perfis com um CTD da superfície até 100 m; ainda, foram realizados perfis verticais através de sonda perfiladora SCAMP para obtenção de dados de clorofila-a em C1. Para obter os dados de clorofila-a em C2 e C3, foi coletada água com auxílio de uma garrafa de Niskin. Foi observado um pico subsuperficial deste parâmetro aproximadamente a 70 m de profundidade. A diversidade de espécies foi muito alta (3,60 ± 0,36 bits.ind-1 ), sendo identificados 102 taxa, considerando a menor unidade taxonômica possível de se identificar. Estes taxa estiveram representados por 9 Filos (Dinophyta, Ciliophora, Protozoa, Cnidaria, Annelida, Mollusca, Arthropoda, Chaetognatha, Chordata), com predomínio de organismos pertencentes ao protozooplâncton (dinoflagelados, foraminíferos, radiolários e tintinídeos) e à classe dos Copepoda (náuplios, juvenis e adultos). Copepoda destacou-se com cerca de 60 espécies, dentre as quais Aetideus australis e Aetideus giesbrechti foram registradas pela primeira vez para o Brasil e o ASPSP, respectivamente. Foi observada uma estratificação na coluna d’água em duas camadas (acima e abaixo da termoclina) diferentes significativamente uma da outra: superfície (L1, L2 e L3) e subsuperfície (L4 e L5). Os organismos puderam ser separados em três grupos: os que se distribuíram por toda coluna d’água (Dinoflagelados, Copepoda (Náuplio), Oithona spp., Oncaea spp.), os que ocorreram em águas superficiais (Clausocalanus furcatus, Farranula gracilis, Appendicularia) e os que parecem evitar águas acima da termoclina média (Ostracoda, Aetideus spp., Haloptilus spp.). Através do uso da WMD (Weighted Mean Depth), não foi identificado um padrão típico de migração vertical diária em nenhum taxa no presente estudo, fato já mencionado para organismos de classes de tamanho menores, sendo geralmente o padrão de migração vertical atribuído a organismos zooplanctônicos de classes de tamanho maior. Não foram observadas diferenças significativas entre os períodos diurno e noturno bem como não foi observada uma variação temporal nem a curto (C2 ≠ C3) nem a longo prazo (C1 ≠ C2 e C3). Deste modo, esta dissertação descreve, pela primeira vez, padrões de distribuição vertical dos principais taxa e constata a ausência de padrões de MVD em organismos microzooplanctônicos no ASPSP. Além disso, mostra a alta diversidade destes organismos neste ambiente oceânico tropical, destacando a necessidade do desenvolvimento de mais estudos envolvendo a estrutura básica desta comunidade.
This dissertation consists of two manuscripts. The first was designed with the intuite of answer the main objective of the dissertation: characterize the vertical migration of microzooplankton of Saint Peter and Saint Paul Archipelago (SPSPA). From the samples analised, it was still possible to obtain an additional manuscript, recording the firt occurrence of Aetideus australis to Brazil e Aetideus giesbrechti to SPSPA. For this, diurnal and nocturnal sampling were carried out in three campaigns (C1: June/2010; C2: September/2011; C3: October/2011), in two fixed stations, one in the East (S1) and another to the West (S2) from SPSPA. Vertical hauls with plankton net with a closing system Nansen type and mesh size of 64 μm were made, considering five predetermined layers of 20 m. (L1: 0-20 m, L2: 20-40 m, L3: 40-60 m, L4: 60-80 m and L5: 80-100 m). Additionally, to characterize the thermohaline structure, CTD profiles were obtained from surface to 100 m depth; and vertical profiles were carried out using a Self Contained Autonomous MicroProfiler SCAMP in C1 to obtain data of chlorophyll-a. To obtain data of chlorophyll-a in C2 and C3, water was collected with the support of a Niskin bottle. A chlorophyll-a subsurface peak of this parameter was observed at approximately at 70 m depth. Species diversity was very high (3.60 ± 0.36 bits.ind-1 ), being identified 102 taxa, considering the smallest taxonomic unit possible to be identified. These taxa have been represented by 9 Phyla (Dinophyta, Ciliophora, Protozoa, Cnidaria, Annelida, Mollusca, Arthropoda, Chaetognatha, Chordata). Among these, predominated organisms belonging to protozooplankton (dinoflagellates, foraminiferans, radiolarians and tintinnids) and to Copepoda (nauplii, juveniles and adults). Copepoda showed highest richness with 60 species, among which Aetideus australis e Aetideus giesbrechti was register for the first time to Brazil and SPSPA, respectively. A stratification was observed in the water column separing in two layers (above and below the thermocline) significantly different from each other: surface (L1, L2 and L3) and subsurface (L4 and L5). The organisms presented three groups: those who was distributed throughout the water column (Dinoflagellates, Copepoda – nauplius –, Oithona spp., Oncaea spp.), those who occurred in superficial waters (Clausocalanus furcatus, Farranula gracilis, Appendicularia) and those that seem to avoid water above the medium thermocline (Ostracoda, Aetideus spp., Haloptilus spp.). Through the use of WMD (Weighted Mean Depth), it was not identified a typical pattern of daily vertical migration (DVM) to none taxa in the present study. This fact was already mentioned to organisms of smaller size classes, as vertical migration pattern being generally attributed to zooplanktonic organisms of larger size. No significant differences were observed between day and night periods and it was not observed a temporal variation nor at short (C2 ≠ C3) or long term (C1 ≠ C2 e C3). Thus, this work describes, for the first time, patterns of vertical distribution of the main taxa and notes the lack of patterns of DVM in microzooplanktonic organisms in the SPSPA. Furthermore, it shows the high diversity of these organisms in this tropical ocean environment, highlighting the need to develop more studies involving the basic structure of this community.

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21

Siminoff, Faren Rhea. "Crossing the sound : the rise of Atlantic American communities in seventeenth-century Long Island /." New York : New York university press, 2004. http://catalogue.bnf.fr/ark:/12148/cb39286377g.

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22

Ewens, Vicky Jane. "An odontological study of ovicaprine herding strategies in the North Atlantic islands : the potential of dental enamel defects for identifying secondary product utilisation in an archaeological context." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5106.

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Abstract:

Recent debate concerning the suitability of mortality profile analysis for identifying secondary product utilisation within archaeozoological assemblages has prompted the search for alternative methodologies. This research explores the potential of using weaning age to provide insight into herding strategies in ovicaprines, determined through the prevalence of developmental enamel defects. A histological methodology was developed, adapted to the specific nature of sheep molars through an understanding of formation processes and enamel structures. This established a relationship between weaning and developmental defects in modern sheep, revealed as distinct patterns in defect distribution within the enamel. Based on historical/archaeological data a weaning age model was developed for the North Atlantic region by which herding strategies could be recognised, specifically: mixed milk/meat subsistence, with an emphasis on milk (0-2 months) or on meat (2-4 months), and the optimisation of meat and/or wool (4-6 months). This methodology was then tested on archaeological material to interpret husbandry at Iron Age and Norse/Viking period sites. The results of this analysis showed that interpretations were in general agreement with those of mortality profile and correspondence analysis conducted as a methodological comparative. Some disparity, however, highlighted the ability of this new technique to provide more sensitivity in cases of mixed subsistence systems, possibly identifying the economic focus of husbandry, or where mortality profiles are confused. It was concluded that the study of weaning age has potential to provide valuable insight into ovicaprine husbandry in archaeological contexts, adding to the understanding of faunal assemblages, especially when supported with other evidence.

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23

Lamb, Deborah E. S. "Modelling an island landscape in the North Atlantic Iron Age. The interpretation of monuments and resources in order to understand local factors influencing settlement and social organisation." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5445.

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An area of Shetland is examined in order to identify how Iron Age settlements might have related to each other. The study area contains two brochs. An inter-disciplinary approach is used to identify evidence for other Iron Age settlements and the information is presented as a model illustrating the pattern of settlement at different points during the Iron Age. A distinction is drawn between locations containing field archaeology and locations where occupation is predicted on the basis of evidence such as soil quality or place name. The whole model is then examined in order to identify patterns which may suggest changing relationships between settlements and groups of settlements, and the trends and influences behind these. Next an appraisal is made of the settlements¿ relative status and authority during Shetland¿s Early, Middle and Late Iron Age. By looking at the whole landscape through time - before, during and after the Iron Age ¿ the brochs are set in a wider chronological context which takes into account the changing role that these highly visible monuments may have played as socio-economic focal points in a developing landscape. The outcome reveals complexity. Initially the brochs appear to be a focus of settlement patterns but by the end of the Late Iron Age they are rivalled by a non-broch area which shows signs of heightened Pictish influence. Elsewhere in Shetland at this period there is retrenchment to broch-settlements, raising the question of how far developments in the study area are unique to that location.

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24

Lamb, Deborah Elizabeth Stewart. "Modelling an island landscape in the North Atlantic Iron Age : the interpretation of monuments and resources in order to understand local factors influencing settlement and social organisation." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5445.

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An area of Shetland is examined in order to identify how Iron Age settlements might have related to each other. The study area contains two brochs. An inter-disciplinary approach is used to identify evidence for other Iron Age settlements and the information is presented as a model illustrating the pattern of settlement at different points during the Iron Age. A distinction is drawn between locations containing field archaeology and locations where occupation is predicted on the basis of evidence such as soil quality or place name. The whole model is then examined in order to identify patterns which may suggest changing relationships between settlements and groups of settlements, and the trends and influences behind these. Next an appraisal is made of the settlements' relative status and authority during Shetland's Early, Middle and Late Iron Age. By looking at the whole landscape through time - before, during and after the Iron Age - the brochs are set in a wider chronological context which takes into account the changing role that these highly visible monuments may have played as socio-economic focal points in a developing landscape. The outcome reveals complexity. Initially the brochs appear to be a focus of settlement patterns but by the end of the Late Iron Age they are rivalled by a non-broch area which shows signs of heightened Pictish influence. Elsewhere in Shetland at this period there is retrenchment to broch-settlements, raising the question of how far developments in the study area are unique to that location.

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25

Joher, Sais Sergi. "Macroalgal-dominated coastal detritic bottoms of the Mediterranean Sea and the Northeastern Atlantic: description, distribution and sampling methodologies." Doctoral thesis, Universitat de Girona, 2016. http://hdl.handle.net/10803/385353.

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En aquesta tesi es van descriure els principals fons algals del detrític costaner de la plataforma continental de Mallorca i Menorca (illes Balears, Espanya), i es van proposar mètodes efectius per al seu mostreig tant a nivell de paisatge com de comunitat. Així, en primer lloc, es van identificar i caracteritzar sis paisatges algals principals a partir de les mostres recol·lectades mitjançant l’arrossegament de fons, que permet mostrejos en àrees extenses. Seguidament, es van descriure algunes de les comunitats presents en aquests paisatges (maërl de Spongites fruticulosus, bosc de Laminaria rodriguezii i llit de Peyssonnelia inamoena) a partir de mostres obtingudes amb la draga Box-Corer i el patí epibentònic, que permeten mostrejos en àrees més reduïdes que l’arrossegament de fons. Finalment, la comparació qualitativa de dades pròpies i d’altres publicades en la bibliografia va permetre avaluar la composició i la distribució de les comunitats dominades per macroalgues dels fons detrítics del Mediterrani i l’Atlàntic Nord-oriental.
This thesis aims to describe the main algal-dominated coastal detritic bottoms of the continental shelf off Mallorca and Menorca (Balearic Islands, Spain), and provide effective methods for their sampling. Firstly, six main algal assemblages were identified and characterized thanks to the samples collected by means of bottom trawl, as it allows sampling in extensive areas. Moreover, the description of some communities that characterized some of the algal assemblages (maërl of Spongites fruticulosus, Laminaria rodriguezii forest and Peyssonnelia inamoena bed) were performed with samples obtained with the Box-Corer dredge and the beam trawl, which allowed sampling on smaller areas than bottom trawl. Finally, the qualitative comparison of our own data and data from published studies allowed to assess the composition and the distribution of the macroalgal-dominated communities of the coastal detritic bottoms from the Mediterranean and the Northeastern Atlantic.

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Delgado, Cláudia Maria Neves. "Gonad development and hormone titres in Loggerhead Sea Turtles (Caretta caretta) in the NE Atlantic." Doctoral thesis, Universidade da Madeira, 2008. http://hdl.handle.net/10400.13/32.

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The study proposed to describe sexual development in pelagic stage loggerhead sea turtles Caretta caretta and compare this to hatchlings and adults. It is meant as an ontogenic approach, in order to understand reproductive development and population composition and their dynamics in the pelagic environment. The study focused on the pelagic loggerheads that are found in the waters offshore Madeira Island (Portugal) in the North-eastern Atlantic and use it as a developmental habitat. The innovating character of this work relied on the lack of any description regarding the gonad ontogenesis and reproductive development for the pelagic stage in any of the 7 existing sea turtle species, all of them in danger of extinction. Three methods were used to diagnose the sex of each juvenile individual and asses the level of reproductive development: (1) laparoscopy, (2) gonad biopsy and (3) the assessment of two sex steroids circulating levels, namely testosterone and estradiol. In order to cover all life stages and compare data obtained for the juvenile stage, hatchlings and nesting female adults were sampled at the nearest nesting rookery at Boa Vista Island in the Cape Verde Archipelago. Gonads from dead hatchlings were collected for gonad histology and blood was collected from nesting females for sex steroids assessment. Laparoscopies revealed to be a valid sexing method for the juvenile stage, since gonads are morphologically differentiated at these size classes. Moreover, laparoscopy was validated using gonad histology. Gonad histology of juveniles showed that gonads are already completely differentiated into ovaries or testes at the size classes examined, but development seems to be quiescent. Males present already developed seminiferous tubules with spermatogonia lining the interior of the seminiferous tubule. Female gonads present oocytes at different development stages, but only oocytes up to stage III were observed. The maximum oocyte diameter in each individual correlated with body size, suggesting that reproductive development is an on-going process in juvenile females. The circulating levels of both testosterone and estradiol in juveniles of both sexes were very low and consistently lower than the ones observed in the nesting females from Boa Vista Island. No bimodal distribution was found for any of the sex steroids analysed and thus circulating hormone levels were not a reliable tool for sexing juvenile individuals with a non-invasive technique. The ratio testosterone:estradiol did not show a bimodal distribution either. The levels of testosterone correlated with sea surface temperature. The fact that temperatures observed during this study were below 24ºC might have hindered a differential testosterone pattern between juvenile males and females. Sex ratios for this population were generated according to laparoscopy results and compared among years and size classes. An overall sex ratio of 2 females for each male was found, but they varied among size classes but not among years. Possible causes for the sex ratios observed are discussed. This study is a contribution to our knowledge on the pelagic stage of loggerhead turtles, namely on the population structure regarding sex ratio, which is a vital tool for implementing conservation strategies.
Orientadores: Thomas Dellinger and Adelino Canário

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Bonfardeci, Alessandro. "Paleoclimatic and Paleoceanographic reconstruction of the Pleistocene‐ Holocene through the study of planktonic foraminifera of two sedimentary cores collected in North Atlantic Ocean, southwest of the Azores Islands." Thesis, Paris, Muséum national d'histoire naturelle, 2017. http://www.theses.fr/2017MNHN0027.

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Dans le système climatique global, l’océan Atlantique Nord est considéré comme une région très sensible qui joue un rôle crucial pour la dynamique de l’hémisphère nord via la circulation méridienne de retournement de l'océan Atlantique (AMOC), dont fait partie le système de front/courant des Açores. La thèse a pour but d’analyser les interactions hydrographiques et climatiques complexes dans la région des Açores, pour le Pléistocène moyen‐Holocène, par l’analyse des foraminifères planctoniques de deux carottes prélevées en 2013 (Oceanograflu 2013), dans le segment OH1 de la ride médio-atlantique. La thèse est structurée en trois chapitres/articles qui présentent les principaux résultats et leur interprétation. Le premier article a pour but d’établir le modèle d’âge le plus précis possible et de tracer l’histoire de la production/préservation des carbonates dans la région des Açores, au cours du dernier cycle glaciaire. Pour ce faire, les valeurs de carbonate et δ18OG.ruber des deux carottes ont été analysées à haute résolution. Par ailleurs, l’application de la «Modern Analog Technique» à l’analyse des assemblages des foraminifères planctoniques a permis d’estimer les variations de température des eaux de surface (SST-mat). Les courbes d’abondance des espèces résistantes et sensibles à la dissolution ont permis de mettre en évidence d’éventuels intervalles de plus forte dissolution. La partie supérieure de chaque carotte a été datée par spectrométrie de masse (AMS)14C sur les tests de foraminifères. Le modèle d’âge adopté se base également sur la corrélation entre les courbes de δ18OG.ruber et l’enregistrement haute résolution du δ18OG.bulloides de la carotte MD95-2042 (Shackleton et al. 2000) de la marge ibérique, récemment recalibrée en utilisant les données synthétiques LS16 de δ18O (Lisiecki and Stern 2016) relatives aux foraminifères benthiques. L’analyse spectrale a permis de démontrer que les oscillations des valeurs de carbonate et du δ18OG.ruber, lors des derniers 144ka, sont contrôlées par un forçage climatique (orbital et sub-orbital) dans la région des Açores. La comparaison des courbes de carbonate et celles des espèces résistantes à la dissolution, pour les deux carottes situées à des profondeurs différentes, a permis de montrer les variations verticales de la lysocline de la calcite, en particulier lors des évènements de refroidissement plus extrêmes, par exemple à 22,1 kyr avec une remontée de la lysocline de 1000m environ. Le deuxième article essaie de reconstituer la variabilité complexe de l’hydrographie et de la paléoproductivité de l’Atlantique centre Nord lors des derniers 144 kyr grâce à l’analyse des assemblages des foraminifères planctoniques combinée à celle des variations de la température des eaux de surface (SST‐mat). Les fluctuations d’abondance d’espèces actuellement caractéristiques de masses d’eau et/ou des systèmes de front/courant dans l’Atlantique Nord ont été utilisées comme traceurs paléocéanographiques. Cette approche a permis d’évaluer la migration latitudinale/longitudinale du système de front/courant des Açores durant le Quaternaire récent ainsi que celle d’autres fronts et/ou courants caractéristiques de l’Atlantique centre Nord. Le troisième article se focalise sur la variabilité du groupe G. ruber gr. dans la région des Açores. G. ruber a été considéré comme un plexus regroupant plusieurs autres espèces et sous espèces. Plus récemment, des études moléculaires et géochimiques mis en évidence la présence de plusieurs génotypes au sein du plexus G. ruber, ce qui implique l’existence de plusieurs (sous‐) espèces avec des modes de calcification et des préférences écologiques différentes. Malgré l’abondante littérature récente sur ce sujet, les liens entre ces différents génotypes, variants morphologiques, préférences écologiques, et modes de calcification ne sont pas encore très bien compris. (...)
In the global climatic system, the North Atlantic Ocean is considered as a highly sensitive region, which plays a crucial role in the Northern Hemisphere dynamics through the so‐called Atlantic Meridional Overturning Circulation (AMOC) system, of which the Azores Front/Current System represents an important part. The main aim of the thesis is to reconstruct the complex hydrographic and climatic interactions in such a climatically‐sensitive area during middle Pleistocene to Holocene through the analysis of the planktonic foraminifera from two cores collected in the OH1 segment of the Mid‐Atlantic Ridge (MAR) south‐westward of the Azores archipelago during the Oceanograflu 2013 cruise. The manuscript is structured in three chapters presenting the major results and their interpretation (...)

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Genini, Julieta [UNESP]. "Reproductive phenology and fruit production on a land bridge island in the brazilian atlantic forest." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/87855.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
As florestas tropicais estão entre os ambientes mais produtivos do planeta, sendo que a quantidade de frutos kg/ha pode chegar a 180-1000 kg/ha. Apesar dessa alta produtividade, a fenologia é altamente sazonal, ocorrendo períodos de escassez de recursos e alta produtividade no mesmo ano e/ou entre anos. Os frugívoros exibem uma ampla variedade de adaptações comportamentais e ecológicas para superar esses períodos de escassez. O presente trabalho avaliou as variações temporais na disponibilidade de frutos consumidos por vertebrados frugívoros na Ilha Anchieta, São Paulo, Brasil. Nós procuramos responder às seguintes questões: Os padrões de frutificação e disponibilidade de frutos diferem entre arbóreas e palmeiras? e Os padrões fenológicos de frutificação diferem entre grupos de palmeiras com diferentes síndromes de dispersão?. Os padrões fenológicos foram sazonais para ambos os grupos, no entanto, as datas de ocorrência dos eventos de frutificação foram diferentes. A produção de frutos também foi diferente entre palmeiras e arbóreas, sendo que as palmeiras constituíram mais de 80 por cento do total da biomassa coletada. Os padrões fenológicos foram diferentes entre as palmeiras com diferentes sub-síndromes de dispersão (dispersas por roedores, mistas e aves) fornecendo recursos alimentares para diferentes grupos de frugívoros ao longo do ano. As palmeiras poderiam constituir um recurso alimentar alternativo em períodos de baixa disponibilidade de frutos embora não forneçam recursos para os diferentes tipos de frugívoros da Ilha Anchieta o ano todo.
Tropical rainforest is considered one of the world s most productive habitats where fruit biomass ranges between 180-1000 kg/ha/yr. Despite this broad fruit production, phenology is highly seasonal in tropical forests, showing alternate periods of fruit scarcity and high resource production both in the same year and/or between different years. Frugivores exhibit a variety of ecological and behavioral adaptations to overcome these fluctuations. We evaluate the temporal variation in the availability of fruits consumed by vertebrate frugivores on Anchieta Island, in the Brazilian Atlantic Forest, Northeast São Paulo State. We aim to answer the following questions: Do fruiting patterns and the availability of fruits consumed by vertebrate frugivores differ between palms and trees? Do palm fruiting patterns differ among seed dispersed groups (rodent, mixed and bird)? Phenological patterns were seasonal for both trees and palms; however, the times of occurrence of fruiting differed. Fruit fall biomass was also different between trees and palms, and palms constituted more than 80 percent of the overall fruit fall biomass. Phenological patterns differed between the seed dispersed palms groups (rodent, mixed and bird seed dispersed palms) providing food resources in distinct periods for different assemblages of vertebrate frugivores. Palms may constitute an alternative food resource in periods of low fruit availability, although they do not provide resources for the entire assemblage of vertebrate frugivores on Anchieta Island all year.

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Genini, Julieta. "Reproductive phenology and fruit production on a land bridge island in the brazilian atlantic forest /." Rio Claro : [s.n.], 2006. http://hdl.handle.net/11449/87855.

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Resumo: As florestas tropicais estão entre os ambientes mais produtivos do planeta, sendo que a quantidade de frutos kg/ha pode chegar a 180-1000 kg/ha. Apesar dessa alta produtividade, a fenologia é altamente sazonal, ocorrendo períodos de escassez de recursos e alta produtividade no mesmo ano e/ou entre anos. Os frugívoros exibem uma ampla variedade de adaptações comportamentais e ecológicas para superar esses períodos de escassez. O presente trabalho avaliou as variações temporais na disponibilidade de frutos consumidos por vertebrados frugívoros na Ilha Anchieta, São Paulo, Brasil. Nós procuramos responder às seguintes questões: Os padrões de frutificação e disponibilidade de frutos diferem entre arbóreas e palmeiras? e Os padrões fenológicos de frutificação diferem entre grupos de palmeiras com diferentes síndromes de dispersão?. Os padrões fenológicos foram sazonais para ambos os grupos, no entanto, as datas de ocorrência dos eventos de frutificação foram diferentes. A produção de frutos também foi diferente entre palmeiras e arbóreas, sendo que as palmeiras constituíram mais de 80 por cento do total da biomassa coletada. Os padrões fenológicos foram diferentes entre as palmeiras com diferentes sub-síndromes de dispersão (dispersas por roedores, mistas e aves) fornecendo recursos alimentares para diferentes grupos de frugívoros ao longo do ano. As palmeiras poderiam constituir um recurso alimentar alternativo em períodos de baixa disponibilidade de frutos embora não forneçam recursos para os diferentes tipos de frugívoros da Ilha Anchieta o ano todo.
Abstract: Tropical rainforest is considered one of the worlds most productive habitats where fruit biomass ranges between 180-1000 kg/ha/yr. Despite this broad fruit production, phenology is highly seasonal in tropical forests, showing alternate periods of fruit scarcity and high resource production both in the same year and/or between different years. Frugivores exhibit a variety of ecological and behavioral adaptations to overcome these fluctuations. We evaluate the temporal variation in the availability of fruits consumed by vertebrate frugivores on Anchieta Island, in the Brazilian Atlantic Forest, Northeast São Paulo State. We aim to answer the following questions: Do fruiting patterns and the availability of fruits consumed by vertebrate frugivores differ between palms and trees? Do palm fruiting patterns differ among seed dispersed groups (rodent, mixed and bird)? Phenological patterns were seasonal for both trees and palms; however, the times of occurrence of fruiting differed. Fruit fall biomass was also different between trees and palms, and palms constituted more than 80 percent of the overall fruit fall biomass. Phenological patterns differed between the seed dispersed palms groups (rodent, mixed and bird seed dispersed palms) providing food resources in distinct periods for different assemblages of vertebrate frugivores. Palms may constitute an alternative food resource in periods of low fruit availability, although they do not provide resources for the entire assemblage of vertebrate frugivores on Anchieta Island all year.
Orientador: Mauro Galetti Rodrigues
Coorientador: Leonor Patrícia Cerdeira Morellato
Banca: Marco Aurélio Pizo Ferreira
Banca: Valesca Bononi Ziparro
Mestre

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30

Richter, Konstantin Alexander. "The historic religious buildings of Ribeira Grande: implementation of christian models in the early colonies, 15th till 17th century, on the example of Cape Verde Islands." Doctoral thesis, Universidade da Madeira, 2008. http://hdl.handle.net/10400.13/256.

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Morgan, Peter. "The sediment sources of Atlantic shore beaches between Montauk Point and Democrat Point, Long Island, New York, USA." Thesis, University of South Wales, 1990. https://pure.southwales.ac.uk/en/studentthesis/the-sediment-sources-of-atlantic-shore-beaches-between-montauk-point-and-democrat-point-long-island-new-york-usa(12dd78fc-93ec-4722-9f0f-ab3dfd455221).html.

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Speculation has arisen regarding the possibility of an additional offshore sediment source on the Atlantic inner shelf south of Long Island, New York, as a result of deficits in recent south shore budgetary estimates. In view of the importance of Long Island's inner shelf as a possible sediment source for other conflicting commercial uses in the future, the present study attempts to compare the known source at Montauk Point with sediments from buried palaeodrainage channels and nearby offshore and to examine the degree to which they may be linked to south shore beaches. Samples from each of these three environments were subjected to S.E.M. analysis using a checklist approach. Qualitative results comparing individual quartz grain surface feature variability with transport distance west of Montauk Point divided the south shore into three sections largely on the basis of mechanically derived and source textures: the distinctive glacial deposits formed in Ronkonkoma moraine at Montauk Point; Headlands section beaches, and Fire Island beaches. Surface feature variability plots and between sample variability plots revealed a more complex pattern of surface feature development than may be expected from what appears to be generally a single alongshore-trending wave dominated regime, which suggests an additional control such as an offshore source. Canonical variate analysis, as well as cluster and factor analyses confirmed qualitative findings and tentatively link offshore lobe deposits with onshore Fire island beaches, and distinguish them from Headlands beaches and Montauk Point. Strong supporting and complementary links between qualitative results, photographic evidence and subsequent statistical analysis suggest that the technique employed is a useful and valid sedimentological tool.

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Mauad, Luana Paula. "Comunidades vegetais em quatro pães-de-açúcar no Estado do Rio de Janeiro." Universidade do Estado do Rio de Janeiro, 2013. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=4826.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Os afloramentos rochosos apresentam flora peculiar, sendo constituídos de habitats únicos que podem representar barreira para muitas espécies devido às suas condições ambientais diferenciadas do entorno. O Estudo desse tipo de área pode fornecer informações relevantes sobre o processo evolutivo e distribuição das espécies que ali ocorrem. Esta pesquisa teve como objetivos gerar maiores informações sobre ecologia, florística e conservação de comunidades de moitas em quatro pães-de-açúcar do Estado do Rio de Janeiro. São eles o Maciço do Itaoca (Campos dos Goytacazes), o Costão de Itacoatiara (Niterói), o Morro dos Cabritos do Parque Natural Municipal da Prainha e o Monumento Natural dos Morros da Urca e Pão de Açúcar (Rio de Janeiro). Os resultados são apresentados em duas seções, a primeiro trata da florística, estrutura e relações ambientais desse tipo de vegetação; e a segunda aborda a florística e estado de conservação da flora rupícola de forma geral das quatro áreas de estudo. Para a primeira seção foram distribuídas 72 parcelas de 1m x 1m ao longo de três linhas de 50m em cada área amostrada e registrados dados da presença de cada espécie por parcela, área de cobertura e altura dos indivíduos. Também foi verificado o tipo de substrato e tomadas medidas de declividade e profundidade do solo e serrapilheira. No total foram marcadas 288 parcelas nas quatro áreas. Entre as famílias mais importantes para as quatro áreas estão Cactaceae, Bromeliaceae, Orchidaceae e Asteraceae. Os resultados mostram que entre as espécies apontadas com maiores valores de importância estão entre as que exercem maior peso na ordenação dos grupos florísticos evidenciados pela análise de componentes principais (PCA) para as quatro áreas. Uma análise de redundância (RDA) foi realizada e mostrou que as variáveis que mais parecem influenciar a composição florística das moitas são as mais sujeitas aos processos biológicos e dinâmica da vegetação como um todo. Dados acerca do espectro biológico e índices de diversidade e equabilidade também são apresentados nesta seção. Para a 2 seção foram compiladas informações de herbários e coletas realizadas em campo, formando uma listagem geral com 193 espécies rupícolas para as quatro áreas. São apresentados os dados florísticos da vegetação e sua distribuição geográfica. No total 28 espécies são restritas ao Estado do Rio de Janeiro e 68 são endêmicas da Mata Atlântica. Dentre elas, 26 encontram-se inseridas em alguma categoria de ameaça de extinção. As principais ameaças e impactos sobre a vegetação dessas áreas foram abordados no contexto da conservação da flora rupícola encontrada, dentre elas, as mais significativas são o fogo, a mineração e a abertura de novos acessos em encostas com vegetação abundante.
Rock outcrops present peculiar flora, being unique habitats which might be considered a barrier for many species due to their environmental conditions. Studies contemplating this type of habitat can provide relevant information about the evolutionary process and distribution of the species which occur there. The aim of this research is to generate more information on ecology, floristic and conser-vation of plant communities of four pães-de-açúcar in Rio de Janeiro state: Maciço do Itaoca (Campos dos Goytacazes), Costão de Itacoatiara (Niterói), Morro dos Cabritos at Parque Natural Municipal da Prainha and Monumento Natural dos Morros da Urca e Pão de Açúcar (Rio de Janeiro). The results are presented in two sections, the first dealing with the floristic, structural and environmental relationships of this type of vegetation, and the second one dealing with the floristic and conservation status of the rupicolous flora in general of the four study areas. In the first section sampling was carried out by combining lines (transects) and plots. Thus, were distributed 72 plots (1m x 1m) over three lines of 50m in each area. In those plots the presence of each species, area coverage and height of each individual was checked. It was also verified the type of substrate and taken measures of declivity, soil and litter depth. By the end of the field work, a total of 288 plots were marked on those four areas. Cactaceae, Bromeliaceae, Orchidaceae and Asteraceae are among the most important families. The results show that, among the species noted with higher importance value, are those with most influence in shaping floristic groups evidenced by principal component analysis (PCA) for the four areas. A redundancy analysis (RDA) was performed and showed that the variables that seem to influence floristic composition are shaped by the dynamics of vegetation itself. Data about the biological spectrum and species diversity index are also presented in this section. In section 2 were compiled information of herbaria collections and material collected at field excursions, forming a general listing with 193 rupicolous species from the four areas. Floristic data are presented, as well as their geographical distribution. About the species, 28 species are restricted to the state of Rio de Janeiro and 68 are endemic to the Atlantic Forest. Among them, 26 are inserted into some category of endangerment. Major threats and impacts on vegetation in those areas were addressed in the context of conservation of the rupicolous flora found. The most significant are fire, mining and the opening of new access on slopes with abundant vegetation.

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Best, Julia. "Living in liminality : an osteoarchaeological investigation into the use of avian resources in North Atlantic Island environments." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/58668/.

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This thesis explores the use of avian resources within the Scottish and wider North Atlantic Island environment via archaeological bone and eggshell. Birds can provide a range of products including meat, eggs and feathers, however their archaeological investigation has frequently been both overlooked, and limited in its extent and application. By collating pre-existing avian data and combining it with new, in-depth analyses this thesis investigates bird use though time and space; firstly in the Scottish Islands (the primary area of study), and then contextualises this within the wider tradition of fowling archaeologically and historically in Iceland and the Faroe Islands. Mesolithic to Norse Scottish Island bird bone is used to develop our understanding of diet, wild resource exploitation, seasonal fowling activities, habitat use, and movement around the landscape. South Uist in the Outer Hebrides forms a major case study incorporating substantial primary bone analyses from Late Bronze Age to Early Iron Age Cladh Hallan, Norse Bornais and Norse Cille Pheadair. The full Scottish Island dataset is used to consider trends in bird use by period and location. Species presence, juveniles, medullary bone and SEM analysis of eggshell are used to investigate resource acquisition by season and location. The material reveals that seabirds played an enduring role, with key birds such as the gannet, auks, shag, cormorant and gulls being repeatedly exploited. Fowling is focused and diverse, often incorporating targeted species and several opportunistically caught taxa. Birds were acquired both locally and in fowling trips further afield. Variations in avian populations are observed; determining the resources available to human fowlers and investigating the impact of such exploitation. Analysing, integrating and interpreting the archaeological bird remains on this wide temporal and geographical scale has enabled a greater understanding of past bird use and role within North Atlantic Island diet, economy and life.

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Le, Breton Éline. "Differential spreading along the North East Atlantic ridge system and post-breakup deformation of the adjacent continental margins." Rennes 1, 2012. https://ecm.univ-rennes1.fr/nuxeo/site/esupversions/3a45a239-35ea-4751-9544-30854d9008d1.

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La théorie de la tectonique des plaques implique que les plaques lithosphériques soient rigides. Or les reconstructions de l'ouverture de l'océan Atlantique Nord Est, utilisant deux plaques rigides (Eurasie et Groenland), conduisent à des écarts et recouvrements des plaques. De plus, l'ouverture océanique de la zone située entre l'Islande et la zone de fracture de Jan Mayen (JMFZ) fut très complexe, incluant la formation progressive du microcontinent de Jan Mayen et un saut de ride entre la dorsale d'Aegir et de Kolbeinsey. J'ai développé une méthode de reconstruction palinspastique d'ouverture de l'Atlantique Nord Est, à partir de données d'anomalies magnétiques et de zones de fracture, méthode qui permet d'obtenir un bon ajustement des anomalies magnétiques. Le modèle prédit des différences de direction et de taux d'ouverture entre les segments océaniques. Cette ouverture différentielle a induit des mouvements décrochants sénestres le long des zones de fractures océaniques, compatibles avec le développement de structures compressives le long de la marge continentale européenne, (1) de l'Éocène inférieur à l'Oligocène supérieur, le long de la zone de fracture des îles Féroé (FFZ), et (2) de l'Éocène supérieur à Oligocène inférieur, et au Miocène, le long de la JMFZ. Aussi, j'ai mis en évidence, par une étude de terrain, une réactivation Cénozoïque en dextre de la Great Glen Fault, en Ecosse, que j'interprète comme étant due aux mouvements senestres le long de la FFZ. Je suggère également que les forces motrices proviennent du point chaud, actuellement sous l'Islande, qui était en mesure de générer une ouverture différentielle de l'Atlantique Nord Est et les déformations compressives de la marge continentale européenne
One of the main assumptions of the theory of plate tectonics is that all lithospheric plates are rigid. However, reconstructions of the opening of the North East Atlantic Ocean, on the basis of two rigid plates (Eurasia and Greenland), lead to gaps and overlaps between the plates. Also, the area between Iceland and the Jan Mayen Fracture Zone (JMFZ) had a complex spreading history, including progressive separation of the Jan Mayen Microcontinent and a ridge jump from the Aegir to Kolbeinsey Ridge. I have developed a method of palinspastic reconstruction of the opening of the North East Atlantic, using magnetic anomalies and fracture zones. The model ensures a good fit of the magnetic anomalies and predicts differences in the direction and rate of sea-floor spreading between the North East Atlantic ridge systems. This differential spreading generated left-lateral strike-slip deformation along oceanic fracture zones : (1) from Early Eocene to Late Oligocene, along the Faeroe Fracture Zone (FFZ) ; and (2) from Late Eocene to Early Oligocene and during the Miocene, along the JMFZ. Such motion and relative rotation between the oceanic segments are compatible with the development of inversion structures on the North West European Margin at these times. Furthermore, a field study along the Great Glen Fault (GGF), NE Scotland, provided additional evidence for right-lateral reactivation of the GGF during the Cenozoic. I infer this to be a result of left-lateral slip along the FFZ. I also suggest that the driving forces came from the Iceland Mantle Plume, which was in a position to generate differential sea-floor spreading along the NE Atlantic and resulting deformation of the North West European margin

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Berglund, Karin. "Seismic tomography in the source region of the May 29th 2008 earthquake-aftershock-sequence in southwest Iceland." Thesis, Uppsala universitet, Geofysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-187589.

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On May 29th 2008 two earthquakes with moment magnitude of Mw ~6 occurred in the southwestern part of Iceland. The second earthquake struck within only seconds after the first, on a fault ~5 km west from the first fault. The aftershock sequence was recorded by 14 seismic stations during the subsequent 34 days. The recorded earthquakes were detected and located with a Coalesence Microseismic Mapping (CMM) technique. The output data from this program has been used as basis for the tomography algorithm PStomo_eq, which simultaneously inverts for both P- and S-wave velocities and relocates the events. Within the study area of 46×36 km the three-dimensional velocity structure has, successfully but not conclusively, been modeled to depths of ~10 km. The Vp/Vs ratio varies from 1.74 to 1.82 within the study area. The velocity increases with depth starting from 2 km where the P-wave velocity is 4.6 km/s and the S-wave velocity is 2.7 km/s, at a depth of 10 km the P-wave velocity is 6.9 km/s and S-wave velocity is 4.0 km/s. In the horizontal slices a high velocity area is seen in the northwestern part of model. This is interpreted to be caused by a magma body rising up from below and lithifying at high pressure. From cross-sections a large low velocity zone is seen in the western part of model area concentrated above the seismicity. The low velocity anomaly is found between depths of 2 km to 4 km, stretching from 21.5° to 21.2° W. It is interpreted to be caused by high porosity within the area. The depth to the brittle crust is increasing from the western part of the model towards the eastern part, right in the middle of the model it abruptly decreases again. The depth to the base of the brittle crust is increasing from 7 km in west to 9 km in the middle of model.
Den 29:e maj 2008 inträffade två jordbävningar med magnitud Mw ~6 på sydvästra Island. Den första jordbävningen följdes tätt av en andra jordbävning på en förkastning ~5 km väster om den första. Påföljande efterskalvssekvens registrerades av 14 seismiska stationer under 34 dagar efter huvudskalven. De registrerade skalven har detekterats och lokaliserats med en Coalesence Microseismic Mapping (CMM) teknik. Utdata från detta program har använts som grund för tomografin som genomförts med PStomo_eq, en algoritm som inverterar oberoende för både P- och S-vågs hastigheter och samtidigt omlokaliserar eventen. Inom det undersökta området på 46×36 km har en tredimensionell hastighetsmodell, om än inte slutgiltigt, modellerats för djup ned till 10 km. Vp/Vs kvoten varierar mellan 1.74 och 1.82 inom studieområdet. Hastigheterna ökar med ökande djup, på ett djup av 2 km är P-vågs hastigheten 4.6 km/s och S-vågs hastigheten 2.7 km/s och vid 10 km är P-vågs hastigheten 6.9 km/s och S-vågs hastigheten 4.0 km/s. I den nordvästra delen av modellen återfinns en höghastighetszon. Denna tolkas vara orsakad av en magma kropp som stigit och kristalliserat under högt tryck. De vertikala tvärsnitten visar en låghastighetsanomali i västra delen av modellen, koncentrerat ovan seismiciteten. Denna anomali sträcker sig från ett djup på 2 km ned till 4 km, från 21.5° till 21.2° V. Den tolkas vara orsakad av en hög grad av porositet. Djupet för den bräckliga jordskorpan ökar från väster till öster i modellen, för att i mitten abrupt minska igen. Basen av den bräckliga skorpan ökar från 7 km i väst till 9 km i mitten av modellen.

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36

Axford, Yarrow Larue. "Interglacial temperature variability in the high-latitude North Atlantic region inferred from subfossil midges, Baffin Island (Arctic Canada) and Iceland." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3256399.

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37

Cussans, Julia E. "Changes in the size and shape of domestic mammals across the North Atlantic region over time. The effects of environment and economy on bone growth of livestock from the Neolithic to the Post Medieval period with particular reference to the Scandinavian expansion westwards." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5734.

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A large database of domestic mammal bone measurements from sites across Greenland, Iceland, the Faroe Islands, and the Northern and Western Isles of Scotland is presented. The reasons for variations in bone growth of domestic ungulates are examined in detail; nutrition is identified as a key factor in the determination of adult bone size and shape. Possible sources of variation in bone size in both time and space in the North Atlantic region are identified. Four hypotheses are proposed; firstly that bone dimensions, particularly breadth, will decrease with increasing latitude in the study region; secondly that higher status sites will raise larger livestock than lower status sites within the same time period and region; thirdly the size of domestic mammals in the Northern and Western Isles of Scotland will increase in the Later Iron Age, possibly in relation to increased fodder supply; finally at times of environmental degradation (climatic and/or landscape) domestic mammal size will decrease. The latitude hypothesis could only be partly upheld; there is no evidence for increased size with site status; a small increase in size is noted at some Scottish Iron Age sites and varying results are found for the environmental degradation hypothesis. The results are discussed with particular reference to how changes in the skeletal proportions of domestic mammals affect their human carers and beneficiaries. The potential of further expanding the dataset and integrating biometrical data with other forms of evidence to create a powerful tool for the examination of economic and environmental changes at archaeological sites is discussed.
The Division of AGES (University of Bradford), the Andy Jagger Fund (University of Bradford), the Francis Raymond Hudson Fund (University of Bradford), the Viking Society, the Prehistoric Society, SYNTHESIS and the Paddy Coker Research Fund (Biogeographical Society)

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38

Andrew, Tim. "The fishes of Tristan Da Cunha and Gough Island (South Atlantic), and the effects of environmental seasonality on the biology of selected species." Thesis, Rhodes University, 1993. http://hdl.handle.net/10962/d1005128.

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This study focuses on the taxonomy, biogeography and biological aspects of the fishes of Tristan da Cunha and Gough Island in the cental South Atlantic Ocean. Oceanographic measurements were undertaken to determine the position and nature of the Subtropical Convergence (STC) in the vicinity of the islands. The Tristan da Cunha group is thought to be situated on the northern edge of the STC while Gough Island is situated on the southern edge of the front. The seasonal environmental cycle at the islands is characterised by an annual sea surface temperature fluctuation of approximately 5 °C and an annual change in stratification of the water column. It is suggested that this increase in stratification at the STC, brought about in the summer by insolation warming the surface layers of the ocean, enhances primary production. The STC is identified as a unique habitat for fishes and as an important barrier to dispersal of species in the Southern Ocean. The present study has produced 18 new distributional records from the shelf waters of Tristan da Cunha and Gough Island. The fish fauna known from the shelf waters of these islands is reviewed, and a diagnosis, synonymy, and in some cases an illustration are provided. For certain species, brief notes on their biology, relative abundance and seasonal distribution are included. An analysis of the ichthyofaunal relationships between shallow water areas in the vicinity of the STC has resulted in the identification of a characteristic neritic STC ichthyofauna. The circumglobal distribution of many of these species is thought to be a consequence of a dispersive pelagic phase in their life-cycles. Biological processes in fishes at these islands are temporally and spatially affected by seasonal changes in oceanographic conditions. Seasonal sea temperature variation was identified as being an indicator of other oceanographic phenomena that may affect processes such as growth, reproduction and feeding in fishes at the islands. Most species have a summer spawning season and growth rate increased during the summer months. It was hypothesised that enhanced primary production and a related increase in food quality and availability during the summer were the major factors temporally regulating the growth and reproduction of fishes at the islands. Twenty families of neritic fishes have been recorded in the shelf waters of Tristan da Cunha and Gough Island. Most families are represented by only one species. Because of this a wide range of life-history strategies are apparent in the fauna. Nevertheless, there are a number of common life-history characteristics shared by most of the neritic species. Firstly, the early lifehistory of many species included an extended pelagic phase which might have facilitated colonisation throughout the STC zone in the past, thereby regulating extant species diversity in this region. Secondly, the common occurrence of an extended summer breeding season and iteroparity suggested that these characters also contributed to survival in what is considered to be an unpredictable environment. It would appear that these common characteristics hold the key to the success of many fishes in the STC zone. This study has contributed to our understanding of oceanic island ecosystems and has revealed distributional patterns of fishes that were unknown previously. By focusing on the biological processes of selected species the regulatory role played by local environmental conditions became apparent. The results of this study are also relevant to proposed conservation measures for Tristan da Cunha and Gough Island.

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D'Haijere, Tania. "Biogeography of Atlantic Central Africa - Tridactyle (Orchidaceae): a story of speciation and colonisation on São Tomé and Príncipe." Doctoral thesis, Universite Libre de Bruxelles, 2021. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/325606.

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The general objective of this work is to better understand the mechanisms of diversification of the African flora on the Gulf of Guinea islands. We focused on orchids, one of the three predominant plant families on São Tomé and Príncipe. We selected the genus Tridactyle, wich presents a high level of diversity and of endemism in the archipelago.We first redefined the taxonomical framework, as the genus belongs to a clade in which the taxonomical classification did not correspond to the phylogenetic tree obtained by previous studies. To address these classification problems (paraphyly and polyphyly of nominal genera), we firstly used Sanger sequencing to obtain more molecular markers to better estimate the phylogenetic tree of the Tridactyle-Cyrtorchis clade. We used one nuclear marker, the internal transcribed spacer (ITS), and five chloroplastic markers (matK, rps16, trnC-petN intergenic spacer, trnL-trnF intergenic spacer, ycf1). Then, we combined the phylogenetic information to a morphological survey, including as many specimens as possible for the genera concerned. We recircumscribed the previously paraphyletic genus Tridactyle, as well as three other genera within the Tridactyle-Cyrtorchis clade (Rangaeris, Ypsilopus and Podangis), and we described two genera with our collaborators, Aziza and Planetangis. We also described six species new to science, two from East Africa and four from São Tomé and Príncipe. Indeed, the morphological diversity of the Tridactyle in the Gulf of Guinea islands has been misevaluated, such that wrong names have been attributed to species new to science.Once this taxonomic work was achieved, we have focused on two other studies: a biogeographic analysis of Tridactyle, to understand the origin and mechanisms generating its diversity in São Tomé and Príncipe, and a phylogeographic study to analyse the genetic variation and geographical distribution of Tridactyle tridactylites, distributed on the archipelago as well as on the continent. These studies were based on DNA sequence variation of the chloroplast genome and ribosomal DNA genes and the data were generated through Illumina Next Generation Sequencing (NGS), which allowed us to include herbarium specimens for which the classic Sanger method did not give satisfactory results.Our study showed that all Tridactyle species currently found on São Tomé and Príncipe colonised the archipelago independently, and that the current species diversity on the islands is the result of allopatric divergence between the islands and the continent, following island colonisation.- 20 -The intraspecific study revealed a high genetic diversity for Tridactyle tridactylites individuals present on Príncipe, which is not common on oceanic islands, but could be a signal that the island was a refuge for the species during the climatic changes related to ice ages. An approximate Bayesian computation analysis (ABC) of the geographic distribution of genetic variation in Atlantic Central Africa and West Africa favoured a hypothesis of recolonisation of the continent from the island rather than a colonisation of the island from the continent. It is possible that the dust-like seeds used wind currents moving from the islands to Central and West Africa as a mean of travel.The work presented here stresses the importance of conducting such studies on more orchid genera, but also on the two other main families of São Tomé and Príncipe, Rubiaceae and Euphorbiaceae. We made a first step toward a better understanding of the mechanisms of diversifications on the Gulf of Guinea islands, but only with a larger number of studies on diverse families and genera, we could draw more general conclusions about these mechanisms for the flora of the archipelago.With regard to the limitations of our study, we were not able to include all species of the genus, especially species from the Democratic Republic of Congo or East Africa. Sampling in the African rainforests is currently not uniformly carried out, and could be improved. Another way to increase sampling is to use new NGS sequencing methods to extract DNA from herbaria preserved in European Herbarium institutions, and obtain genetic information from the chloroplast and ribosome as we have done, but potentially from low-copy nuclear genes as well.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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40

Cussans, Julia Elise. "Changes in the size and shape of domestic mammals across the North Atlantic region over time : the effects of environment and economy on bone growth of livestock from the Neolithic to the post-medieval period, with particular reference to the Scandinavian expansion westwards." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5734.

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Abstract:

A large database of domestic mammal bone measurements from sites across Greenland, Iceland, the Faroe Islands, and the Northern and Western Isles of Scotland is presented. The reasons for variations in bone growth of domestic ungulates are examined in detail; nutrition is identified as a key factor in the determination of adult bone size and shape. Possible sources of variation in bone size in both time and space in the North Atlantic region are identified. Four hypotheses are proposed; firstly that bone dimensions, particularly breadth, will decrease with increasing latitude in the study region; secondly that higher status sites will raise larger livestock than lower status sites within the same time period and region; thirdly the size of domestic mammals in the Northern and Western Isles of Scotland will increase in the Later Iron Age, possibly in relation to increased fodder supply; finally at times of environmental degradation (climatic and/or landscape) domestic mammal size will decrease. The latitude hypothesis could only be partly upheld; there is no evidence for increased size with site status; a small increase in size is noted at some Scottish Iron Age sites and varying results are found for the environmental degradation hypothesis. The results are discussed with particular reference to how changes in the skeletal proportions of domestic mammals affect their human carers and beneficiaries. The potential of further expanding the dataset and integrating biometrical data with other forms of evidence to create a powerful tool for the examination of economic and environmental changes at archaeological sites is discussed.

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41

Dows, Benjamin. "Roles of seed dispersal and environmental filters in establishment of the dominant shrubs: Morella cerifera and M. pensylvanica, on an Atlantic barrier island." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3372.

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Patterns of the expansion of woody cover into grasslands on barrier islands of the Virginia coast were investigated. Seed dispersal of the dominant shrub Morella spp., was sampled deploying seed traps (n = 82) throughout a landscape under shrub encroachment pressure on Hog Island, VA. Traps were placed underneath: fruiting Morella, non-fruiting Morella, co-occurring species (Iva frutescens and Baccharis halimifolia) and in grass land, (no shrub cover). Environmental filters that act upon dispersed seeds and subsequently determine establishment patterns were also investigated. Dispersal distribution throughout the encroachment zone was leptokurtic and dispersal among cover types suggest co-occurring shrub species facilitate dispersal by functioning as bird perches. Interaction of biotic and abiotic factors mediate a complex process of establishment by influencing dispersal, germination and seedling survival to ultimately determine distribution patterns of woody plants in coastal environments.

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42

Rose, Juliet. "The Role of Strategic Partnerships, Policy and Funding Mechanisms in Strategic Management Planning for the Crown Wastes on St Helena Island, South Atlantic." Thesis, University of Reading, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485348.

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St Helena in the South Atlantic has undergone centuries ofdegradation, followed by decades ofunmanaged re-vegetation. The island's landscape is dominated by the Crown Wastes: wastelands ofbare soil and sparse mainly exotic scrub which accounts for over 60% ofthe island's land area. The Crown Wastes need a managed recovery programme that can meet the island's needs through a range ofdifferent objectives that include endemic plant conservation, agriculture, forestry, tourism and housing. Implementing an environmental management approach with complex and varied objectives carnes with it a considerable management responsibility, and a requirement for sufficient and consistent technical, financial and human capacity. However, extremely limited hmnan, technical and financial resources are available for environmental management on St Helena due a range ofpolitical, social and economic issues associated with the island. This study looks specifically at three ofthe obstacles integral to effective environmental management and recovery on St Helena and the Crown Wastes in particular: b~ding capacity; resources; and guidance and explores the role ofstrategic partnerships. (Government and NGO), funding and policy mechanisms in helping to overcome them. These three areas are explored uSing a combination ofstakeholder and documentary analysis methodologies. A semi-structured interview technique was chosen for stakeholder consultation and the results displayed as role- and conceptually-ordered matrices.This study concludes that while the island faces a complex range of challenges to environmental management, there is a no less daunting array ofopportunities that will require considerable effort to-exploit effectively. Strategic partnerships, policy and funding mechanisms all have specific and important roles to play in the development ofa . strategic environmental management plan for the Crown Wastes.

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Tempera, Fernando. "Benthic habitats of the extended Faial Island shelf and their relationship to geologic, oceanographic and infralittoral biologic features." Thesis, University of St Andrews, 2009. http://hdl.handle.net/10023/726.

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This thesis presents a new template for multidisciplinary habitat mapping that combines the analyses of seafloor geomorphology, oceanographic proxies and modelling of associated biologic features. High resolution swath bathymetry of the Faial and western Pico shelves is used to present the first state-of-the-art geomorphologic assessment of submerged island shelves in the Azores. Solid seafloor structures are described in previously unreported detail together with associated volcanic, tectonic and erosion processes. The large sedimentary expanses identified in the area are also investigated and the large bedforms identified are discussed in view of new data on the local hydrodynamic conditions. Coarse-sediment zones of types hitherto unreported for volcanic island shelves are described using swath data and in situ imagery together with sub-bottom profiles and grainsize information. The hydrodynamic and geological processes producing these features are discussed. New oceanographic information extracted from satellite imagery is presented including yearly and seasonal sea surface temperature and chlorophyll-a concentration fields. These are used as proxies to understand the spatio-temporal variability of water temperature and primary productivity in the immediate island vicinity. The patterns observed are discussed, including onshore-offshore gradients and the prevalence of colder/more productive waters in the Faial-Pico passage and shelf areas in general. Furthermore, oceanographic proxies for swell exposure and tidal currents are derived from GIS analyses and shallow-water hydrographic modelling. Finally, environmental variables that potentially regulate the distribution of benthic organisms (seafloor nature, depth, slope, sea surface temperature, chlorophyll-a concentration, swell exposure and maximum tidal currents) are brought together and used to develop innovative statistical models of the distribution of six macroalgae taxa dominant in the infralittoral (articulated Corallinaceae, Codium elisabethae, Dictyota spp., Halopteris filicina, Padina pavonica and Zonaria tournefortii). Predictive distributions of these macroalgae are spatialized around Faial island using ordered logistic regression equations and raster fields of the explanatory variables found to be statistically significant. This new approach represents a potentially highly significant step forward in modelling benthic communities not only in the Azores but also in other oceanic island shelves where the management of benthic species and biotopes is critical to preserve ecosystem health.

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44

Fortkamp, Diana. "Metabólitos secundários produzidos por fungos endofíticos isolados de Anthurium alcatrazense e Begonia spp." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-17072018-184806/.

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Os produtos do metabolismo secundário, também conhecidos por produtos naturais, representam uma fonte inexplorada de compostos com atividade biológica. Os micro-organismos, entre eles os endófitos, são fontes promissoras de obtenção dessas substâncias. Assim sendo, essa pesquisa visou obter compostos de importância biotecnológica produzidos por fungos endofíticos isolados de folhas das plantas Anthurium alcatrazense, Begonia venosa e B. fischeri. Para isso, 5 linhagens de fungos endofíticos isolados dessas plantas (códigos P7BDA1F2, P8BDA1F1, AM29, D28 e D29) foram estudadas. A identificação desses micro-organismos foi realizada por meio de análises morfológicas e moleculares, revelando serem estas linhagens Hymenochaete-like, Trichoderma sp., Neopestalotiopsis sp., Aspergillus sp. e Diaporthe sp., respectivamente. A partir do extrato bruto de Hymenochaete-like (código P7BDA1F2) foram isolados os compostos 5,7-dimetoxiftalida e metil orselinato, os quais foram testados contra Leishmania (L.) infantum e alvo do proteassoma e não apresentaram atividade. A partir do extrato bruto de Trichoderma sp. (código P8BDA1F1) foram isolados os compostos trilongins BI-BIV. Estes apresentaram atividade inibitória ao fitopatógeno C. gloeosporioides, com MIC de 40, 320, 160 e 310 μM, respectivamente. As trilongins BI-BIV foram testadas contra a subunidade ChTL do proteassoma e apresentaram os valores de IC50 de 6,5 ± 2,7; 4,7 ± 1,8; 6,3 ± 2,2; e 2,7 ± 0,5 μM. Os compostos também foram testados ex vivo contra os amastigotas intracelulares de Leishmania (L.) infantum, mas não apresentaram seletividade. A partir do extrato bruto de Neopestalotiopsis sp. (código AM29), foi isolado um composto de massa molecular 366,0570 Da (que pode ser inédito na literatura), o qual apresentou atividade inibitória ao fitopatógeno P. sojae, com MIC de 312 μg mL-1. A partir dos extratos brutos de Aspergillus sp. e Diaporthe sp. foram isolados 9 compostos, cujas frações precursoras apresentaram atividade contra as bactérias formadoras de biofilme S. aureus e P. aeruginosa. Para a identificação desses compostos, análises adicionais precisam ser realizadas. Este é o primeiro relato do isolamento dos compostos 5,7-dimetoxiftalida e metil orselinato do basidiomiceto Hymenochaete-like. Também está sendo relatada pela primeira vez a atividade antifúngica das trilongins a C. gloeosporioides e contra o alvo do proteassoma, assim como o isolamento de um possível novo composto de Neopestalotiopsis sp. e sua atividade contra P. sojae.
Secondary metabolism products, also known as natural products, represent an unexplored source of compounds with biological activity. Microorganisms, including endophytes, are promising sources of these substances. Thus, this research aimed to obtain compounds with biotechnological importance produced by endophytic fungi isolated from leaves of the plants Anthurium alcatrazense, Begonia venosa and B. fischeri. To this end, 5 endophytic fungal strains isolated from these plants (codes P7BDA1F2, P8BDA1F1, AM29, D28 and D29) were studied. The identification of these microorganisms was carried out by morphological and molecular analyzes, revealing that these strains are Hymenochaete-like, Trichoderma sp., Neopestalotiopsis sp., Aspergillus sp. and Diaporthe sp., respectively. From the crude extract of Hymenochaete-like (code P7BDA1F2) the compounds 5,7-dimethoxyphthalide and methyl orselinate were isolated, which were tested against Leishmania (L.) infantum and proteasome target and showed no activity. From the crude extract of Trichoderma sp. (code P8BDA1F1) the trilongins BI-BIV were isolated. These compounds presented inhibitory activity to the plant pathogen C. gloeosporioides, with MIC of 40, 320, 160 and 310 μM, respectively. The trilongins BI-BIV were tested against the ChTL subunit of the proteasome and showed IC50 values of 6.5 ± 2.7, 4.7 ± 1.8, 6.3 ± 2.2, 2.7 ± 0, 5 μM. The compounds were also tested ex vivo against the intracellular amastigotes of Leishmania (L.) infantum, but did not show selectivity. From the crude extract of Neopestalotiopsis sp. (code AM29), a compound with molecular mass 366.0570 Da (which can be unpublished in the literature) was isolated, which presented inhibitory activity to the plant pathogen P. sojae, with MIC of 312 μg mL-1. From the crude extracts of Aspergillus sp. and Diaporthe sp. 9 compounds were isolated, whose precursor fractions showed activity against the biofilm forming bacteria S. aureus and P. aeruginosa. For the identification of these compounds, additional analyzes need to be performed. This is the first report of the isolation of the compounds 5,7-dimethoxyphthalide and methyl orselinate from the basidiomycete Hymenochaete-like. The antifungal activity of trilongins to C. gloeosporioides and against the proteasome target is also being reported for the first time, as well as the isolation of a possible new compound from Neopestalotiopsis sp. and its activity against P. sojae.

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45

Stone, Brian Jr. "A remote sensing analysis of residential land use, forest canopy distribution, and surface heat island formation in the Atlanta Metropolitan Region." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/22983.

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Dufeu, Valerie. "Human ecodynamics in the North Atlantic : environmental and interdisciplinary reconstructions of the emergence of fish trade in Iceland and the Faeroes, c.800-1480." Thesis, University of Stirling, 2012. http://hdl.handle.net/1893/3652.

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Over the past two decades, environmental history as an approach to the understanding and explanation of historical processes has become gradually fashionable amongst academics; empirical data collected over the North Atlantic proposed new trends with regards to economic patterns during the Viking Age. The increasing number of Viking Age sites exposed in Iceland, the amount of zooarchaeological collections highlighting an abundant presence of fish bones in the overall archaeofauna, together with one’s expertise in environmental history as well as a strong interest in socio-economic development during the Viking Age and medieval periods were many factors which help identify strengths and weaknesses with regards to the understanding of the emergence of commercial fish trade in Iceland, and to a lesser extent, the Faeroe Islands. The thesis proposes a new theory with regards to human adaptation to new environments, and subsequent economic developments based on the commercial exploitation of fish. The interdisciplinary aspect of this project using cultural sediment analysis and zooarchaeology, as well as concepts from anthropology and economic anthropology, allows for the theory to be tested by empirical data.

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47

Samuels, Damian. "Cape-Helena: An exploration of nostalgia and identity through the Cape Town - St. Helena migration nexus." University of the Western Cape, 2018. http://hdl.handle.net/11394/6542.

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Magister Artium - MA (History)
In the following two chapters I will attempt to offer a more systemic account of St. Helena immigration to South African between 1838 and 1948. To date, no such study has been undertaken, despite a vibrant oral tradition amongst the descendants of St. Helena immigrants celebrating their St. Helenian heritage and often, in peculiar fashion, romanticise their Island of provenance. The commencement date for my chosen timeframe emerges from a need to authenticate rather tenuous historical accounts of St. Helena’s first mass emigration for the Cape of Good Hope in 1838. Where cases of migration are discussed, these are either incidences of large-scale 41, often aided, migration and settlement, or of those St. Helena migrant workers initially employed under temporary contacts to work in South Africa, specifically within burgeoning industrial sectors of the late-nineteenth or early-twentieth century South Africa.

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48

Soukop, Robin. "Vliv vulkanického popela na leteckou dopravu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230173.

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This master's thesis deals with the issue of volcanic ash as a complex and its impact on aviation, including the volcanic activity itself (conditions for its existence, for existence of eruptions and their basic products). In addition, the thesis also deals with effect of volcanic ash on aircraft and airports, possibilities of its detection or monitoring as well as mechanism of its spreading in airspace. The emphasis is laid mainly on air incidents related to volcanic ash and on danger it poses to the airspace of the Czech Republic.

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49

Silva, Kelly Cristina da. "Melastomataceae na Marambaia, Rio de Janeiro, Brasil: diversidade taxon?mica, aspectos flor?sticos e estado de conserva??o." Universidade Federal Rural do Rio de Janeiro, 2011. https://tede.ufrrj.br/jspui/handle/jspui/1183.

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Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-08-29T11:54:58Z No. of bitstreams: 1 2011- Kelly Cristina da Silva.pdf: 7307607 bytes, checksum: 8d84ec46e5af2c80b3625d586980819b (MD5)
Made available in DSpace on 2016-08-29T11:54:58Z (GMT). No. of bitstreams: 1 2011- Kelly Cristina da Silva.pdf: 7307607 bytes, checksum: 8d84ec46e5af2c80b3625d586980819b (MD5) Previous issue date: 2011-03-30
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
The Atlantic Forest is one of the world's biodiversity hotspots because of the diversity and high degrees of endemism and threat. Melastomataceae is a plant family typical of this biome, and it is represented by more than 500 species that occur from restingas (sandy coastal plain habitats) to the upper montane forests and high-altitude grasslands. Despite this broad representation, there are few taxonomic studies of this family for this biome, and especially of the flora of Rio de Janeiro state. The present study aims to survey the Melastomataceae at Marambaia, an island included in the Atlantic Forest biome, as well as taxonomic and floristic similarity studies. It has significant ecological importance as a natural refuge for several plant species of the Tropical Moist Forest and for the preservation of genetic heritage. The vegetation types are Submontane Tropical Moist Forest and restinga, and the Melastomataceae is represented by seven genera and 25 species, of which 13 (52%) represent new records for the area. Miconia is the largest genus with 10 species, followed by Tibouchina (6 spp.), Leandra (4 spp.), Clidemia (2spp.) and Huberia, Marcetia and Ossaea (1 sp. each). Descriptions, illustrations, and a key to identify the taxa are provided. Morphological characteristics of leaves, inflorescences, buds, petals, hypanthium, stamens, indumentum, fruits, and seeds are diagnostic to distinguish the taxa. Comments on morphological peculiarities of species and geographical, phenological, and conservation status data are also presented. Three species are cited on the list of endangered species of Rio de Janeiro municipality. Among the vegetation formations, the Submontane Tropical Moist Forest has the highest species richness (23 species), while in restingas the richness is lower, with eight species in forest formations, five species in shrubby formations, and only two species in herbaceous formations. Similarity between the vegetation formations of Marambaia was low, ranging between 4.2% and 40%. Despite the strong relationship between these formations and their physical proximity, the four areas at Marambaia have low species similarity. Key words: Atlantic
A Floresta Atl?ntica ? um dos hotspots mundiais de biodiversidade devido ? elevada diversidade e graus de endemismo e amea?a. Dentre as fam?lias vegetais t?picas desse bioma est? Melastomataceae, com mais de 500 esp?cies e que ocorrem desde as restingas at? as florestas altomontanas e campos de altitude. Apesar dessa numerosa representatividade, poucos s?o os estudos taxon?micos sobre esta fam?lia na flora fluminense. Desse modo, o presente estudo tem como objetivo realizar o levantamento flor?stico da fam?lia Melastomataceae na Marambaia, uma regi?o insular integrada no bioma Floresta Atl?ntica, bem como estudos taxon?micos e de similaridade flor?stica. Ela desempenha significativa import?ncia ecol?gica como um ref?gio natural para diversas esp?cies de plantas da Mata Pluvial e atua na preserva??o do patrim?nio gen?tico. Nessa regi?o insular, onde a cobertura vegetal ? de Floresta Ombr?fila Densa Submontana e Restinga, a representatividade da fam?lia Melastomataceae mostra-se expressiva, constitu?da de sete g?neros e 25 esp?cies, das quais 13 correspondem a novos registros para a ?rea. Miconia ? o g?nero mais numeroso, com 10 esp?cies, seguido por Tibouchina (6 spp.), Leandra (4 spp.), Clidemia ( 2spp.) e Huberia, Marcetia e Ossaea (1 sp. cada). S?o apresentadas descri??es, ilustra??es e chaves para identifica??o dos t?xons. Caracter?sticas morfol?gicas das folhas, infloresc?ncias, ?pice dos bot?es florais e p?talas, hipanto, estames, tipos de indumento, frutos e sementes mostram-se diagn?sticas para a identifica??o dos t?xons. Coment?rios sobre particularidades morfol?gicas das esp?cies e dados geogr?ficos, fenol?gicos e sobre o estado de conserva??o das esp?cies, tamb?m s?o apresentados. Tr?s esp?cies s?o citadas na lista das esp?cies amea?adas de extin??o para o munic?pio do Rio de Janeiro. Dentre as forma??es vegetais analisadas, a Floresta Ombr?fila Densa Submontana apresentou a maior riqueza de esp?cies (23 esp?cies), enquanto nas restingas a riqueza foi menor, com oito esp?cies nas Forma??es Florestais, cinco esp?cies nas Forma??es Arbustivas e apenas duas esp?cies nas Forma??es Herb?ceas. A similaridade entre as forma??es vegetais da Marambaia foi baixa, variando entre 4,2% e 40%. Apesar da elevada rela??o entre essas forma??es e suas proximidades f?sicas na Marambaia, as quatro ?reas guardam poucas semelhan?as na composi??o de esp?cies

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50

Melton, Nigel Duncan. "Archaeological visibility of cultural continuity, contact and change in southern Shetland from the sixteenth to eighteenth centuries AD : a multi-discipline analysis of the evidence for inter-action between different cultural identities in a North Atlantic island community." Thesis, University of Bradford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.645948.

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A multidisciplinary approach, using archaeological and documentary evidence, is used to examine the evidence for cultural contacts, continuity and change in southern Shetland between the sixteenth and eighteenth centuries. Contacts with both the foreign merchants and traders who were operating in the area and those arising from the immigration into the area of large numbers of Scots and Orcadians are considered. Selected artefact types from case studies of a high status site, a crofting township and a trading place are used in this research, along with archaeological economic evidence and documentary evidence. The documentary evidence is used to construct a predictive model of the archaeological record on the site types selected as case studies. The latter use data from the past excavations at Jarlshof, the current excavations at Old Scatness and from targeted sampling of seventeenth century middens at Grutness. The archaeological evidence is shown to reveal a pattern of trading contacts that corresponds to that described in the documentary record. A growing insularity is indicated by a decline in the numbers of items of imported material culture in the course of the seventeenth century. It is suggested that this could in part be linked to climatic deterioration. Archaeological and documentary evidence is presented that may relate to possible climate induced strain in the local whitefish fishery that dominated the trade of the area. Evidence for the historically attested 'Scottification' of the area and its effects on the economy is also demonstrated in both the architectural and material culture records.

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Dissertations / Theses on the topic 'Islands of the Atlantic'

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