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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Field studies of the oxidation of dimethyl sulphide in the atmosphere

Robertson, Leonie January 2000 (has links)
No description available.
2

Magma dynamics of the phonolitic Diego Hernández Formation, Tenerife, Canary Islands

Olin, Paul Hessel, January 2007 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, December 2007. / Includes bibliographical references.
3

El pintor Antonio Torres en la plástica tinerfeña de postguerra, 1940-1958: su posicionamiento artístico y social

Torres Román, Juan Luis 02 February 2001 (has links)
No description available.
4

GIS based models for optimisation of marine cage aquaculture in Tenerife, Canary Islands

Perez Martinez, Oscar January 2002 (has links)
This study focused on the optimisation of offshore marine fish-cage farming in Tenerife, Canary Islands. The main objective was to select the most suitable sites for offshore cage culture. This is a key factor in any aquaculture operation, affecting both success and sustainability. Moreover, it can solve conflicts between different coastal activities, making a rational use of the coastal space. Site selection was achieved by using Geographical Information Systems (GIS) based models and related technology, such as satellite images and Global Positioning System (GPS), to support the decision-making process. Three different cage systems were selected and proposed for different areas around Tenerife. Finally, a particulate waste distribution model (uneaten feed and faeces) was developed, also using GIS, for future prediction of the dispersive nature of selected sites. This can reduce the number of sites previously identified as most suitable, by predicting possible environmental impacts on the benthos if aquaculture was to be developed on a specific site. The framework for spatial multi-criteria decision analysis used in this study began with a recognition and definition of the decision problem. Subsequently, 31 production functions (factors and constraints) were identified, defined and subdivided into 8 sub-models. These sub-models were then integrated into a GIS database in the form of thematic layers and later scored for standardization. At this stage, the database was verified by field sampling to establish the quality of data used. The decision maker's preferences were incorporated into the decision model by assigning weights of relative importance to the evaluation under consideration. These, together with the thematic layers, were integrated by using Multi-criteria Evaluation (MCE) and simple overlays to provide an overall assessment of possible alternatives. Finally, sensitivity analysis was performed to determine the model robustness. The integration, manipulations and presentation of the results by means of GIS-based models in this sequential and logical flow of steps proved to be very effective for helping the decision-making process of site selection in study. On the whole, this study revealed the usefulness of GIS as an aquaculture planning and management tool. Cage systems that can withstand harsh environments were found to be suitable for use over a broader area of Tenerife's coastline. Thus, the more robust self-tensioned cage (SeaStation®) could be used over a greater area than the weaker gravity cages (Corelsa®). From the 228 km2 of available area for siting cages in the coastal regions with depth of 50 m, the suitable area (sum of scores 6, 7 and 8) for siting SeaStation® cages was 61 km2, while the suitable area for SeaStation® and Corelsa® cages was 49 and 37 km2 respectively. Most of the variation between these three cage systems was found among the intermediate suitability scores. It was concluded that the biggest differences in suitable area among cage systems are between Corelsa® and SeaStation® systems, followed by differences between Corelsa® and OceanSpar® cages, and OceanSpar® and SeaStation® respectively. This variability was mostly located on the N and NNW of the island, where waves, both long and short-term, are higher.
5

The importance of horizontal precipitation for growth of juvenile stages of Dragon tree on Canary Island

Lengálová, Klára January 2017 (has links)
Dracaena draco is native to subtropical arid area of Macaronesia. Horizontal precipitation is an important component of water balance in such arid and semiarid areas. Morphological, anatomical and physiological adaptations to drought stress and demonstrated ability to absorb condensed water on the leaves into the stem tissues were discovered at D. draco. The aim of performed measurements was to quantify the importance of horizontal precipitation as an additional source of moisture during the critical period of juvenile stages of D. draco in Anaga (Tenerife). Measuring sets based on lysimeters measured the weight changes of seedlings placed in flowerpots hanging on the weights. The results of measurement proved that the seedlings can partly replace loss of water from evaporation by the water uptake from the atmosphere. Water uptake from the atmosphere took place mainly at night and the water output by transpiration predominated during the day. Horizontal precipitation replaced the evaporation by 6 to 10 % in the first period measured from October and did not replace the evaporation in the second period of measurements that started in January
6

Carbon Isotope Discrimination and Nitrogen Isotope Values Indicate that Increased Relative Humidity from Fog Decreases Plant Water Use Efficiency in a Subtropical Montane Cloud Forest

Mosher, Stella G., M.S. 30 June 2015 (has links)
No description available.
7

Age, récurrence et mécanismes de déstabilisation des flancs des volcans océaniques d'après l'exemple de Tenerife (iles Canaries) / Age, recurrence and triggering mechanisms of flank collapse episodes on ocean islands after the Tenerife Island exemple (Canary Islands)

Boulesteix, Thomas 30 September 2011 (has links)
La croissance des volcans océaniques est fréquemment ponctuée par des effondrements latéraux géants qui peuvent générer des avalanches de débris volumineuses et engendrer des tsunamis dévastateurs. Néanmoins, les causes, les mécanismes et les conséquences de telles déstabilisations, critiques pour la caractérisation des aléas, demeurent largement incompris.L'île de Tenerife (Canaries, Espagne) constitue une cible privilégiée pour étudier ces phénomènes. Son évolution récente inclue le développement d'un volcan central différencié et d'une ride volcanique proéminente le long d'une rift-zone principale NE-SW (NERZ). Durant le dernier Myr, ces systèmes ont été tronqués par trois effondrements de flanc géants, dont la semelle est partiellement accessible à la faveur de galeries souterraines à usage hydrogéologique.Cette thèse développe une analyse systématique des relations entre construction volcanique et instabilités récurrentes le long de l’axe de la NERZ. L'approche inclut des investigations de terrain en surface et dans les galeries, afin de reconnaître et d’échantillonner les séquences volcaniques affectées par chaque effondrement et remplissant leurs structures; la datation K/Ar Cassignol-Gillot sur phases séparées pour en contraindre l’âge précisément ; des reconstructions morphologiques 3D afin d'estimer le volume des édifices et des structures gravitaires; des analyses chimiques sur roches totales, visant à caractériser l’évolution de la composition des laves avant et après chaque déstabilisation.Les nouveaux résultats montrent le fonctionnement intermittent des différents tronçons la NERZ, avec un schéma récurrent comprenant :1) la croissance rapide d'un édifice imposant, dont la charge induit la création de niveaux de stockage superficiels et l’éruption de termes différenciés visqueux, favorisant l'inflation locale de la structure et sa déstabilisation2) la rupture proprement dite, datée à environ 840 ka, 525 ka et 175 ka (glissements de Güimar, La Orotava et Icod, respectivement)3) une réponse éruptive immédiate, impliquant la vidange rapide (<50kyr) du système d’alimentation, et le comblement des loupes de glissement sous des dizaines de km3 de lave.4) Un déplacement consécutif de la construction volcanique vers les secteurs moins matures de la NERZ (moindre épaisseur de l'édifice/moindre pression lithostatique)Nous montrons que les phénomènes de charge/décharge ont une influence primordiale sur le développement des instabilités gravitaires et l'évolution des systèmes d'alimentation des îles océaniques. / The growth of oceanic volcanoes is frequently punctuated by large flank collapses, which can generate voluminous debris avalanches and destructive tsunamis. The causes, the mechanisms and the consequences of such instabilities, crucial for risk assessment, remain poorly understood.Tenerife (Canary Islands, Spain) is a target of particular interest to study such phenomena. Its recent evolution includes the development of a large silicic central volcano and a prominent volcanic ridge along a main NE-SW trending rift zone (NERZ). During the last Myr, these volcanic systems have been truncated by three large flank collapses, the base of which is partly accessible through underground water mining galleries.This thesis develops a systematic analysis of the relationships between volcanic construction and recurrent flank instabilities along the NERZ. Our approach includes field investigations at the surface and in the galleries to identify and sample the volcanic units affected by each landslide and the successions filling their scar; unspiked K/Ar dating (Cassignol-Gillot technique) on fresh separated groundmass to constrain precisely the timing of the landslides; 3-D morphological reconstructions to estimate the volume of the edifices and landslides structures; and whole-rock geochemical analyses to characterize the compositional evolution of the magma prior to and after each collapse event.Our new results show the intermittent functioning of the various sections of the NERZ with a recurrent pattern comprising:(1) The rapid construction of a large volcanic edifice. The resulting load favors the creation of superficial storage levels, the associated evolution of the magma and the eruption of viscous differentiated terms, favoring local inflation of the structure and its destabilization(2) The collapse of a flank of the NERZ, dated at ca. 840 ka, 525 ka, and 175 ka (Güimar, La Orotava and Icod, events respectively)(3) An immediate eruptive response, implying the rapid emptying (<50kyr) of the feeding system and the filling of the landslide scars under tens of km3 of lava.(4) The subsequent displacement of volcanic activity towards the less mature sectors (lower thickness/lower lithostatic pressure).We show here that loading/unloading processes have a strong influence on the development of gravitational instabilities and the evolution of the magma feeding systems on such large intraplate volcanic islands.
8

Evolution magmatique d'un volcan bouclier océanique avant et après une déstabilisation massive de ses flancs : Fogo, Cap Vert et Tenerife, Canaries / Magmatic evolution of oceanic shield volcano before and after a flanc collapse : Fogo, Cape Verde and Tenerife, Canary Islands

Cornu, Mélodie-Neige 19 December 2017 (has links)
Les effondrements massifs de flancs sont des évènements destructeurs qui affectent tous les édifices volcaniques. Ces effondrements peuvent impliquer quelques dizaines, voire centaines de km3 de roche. Les volcans boucliers océaniques, bien que possédant de faibles pentes, sont également affectés par ces épisodes destructeurs, entraînant la formation de tsunamis. Dans le contexte de bouclier océanique, ces déstabilisations n’ont jamais été observées. Actuellement, seules des reliques sont présentes sur les îles volcaniques, avec la présence de cicatrices d’effondrements, de dépôts détritiques en mer ou de dépôts de tsunami sur les îles voisines. Les relations entre le magmatisme des volcans boucliers et les effondrements de flanc sont peu contraintes. Afin de mieux comprendre ces relations, deux effondrements de flanc de volcans boucliers océaniques ont été étudiés : l’effondrement de Monte Amarelo sur l’île de Fogo, dans l’archipel du Cap Vert, et l’effondrement de Güímar, situé sur la rift-zone Nord-Est de Tenerife, dans l’archipel des Canaries. Les deux archipels résultent de l’activité d’un panache mantellique sous la plaque africaine.Les produits volcaniques pré et post-effondrement de ces deux secteurs ont été étudiés d’un point de vue géochimique (majeurs, traces, isotopes Sr-Nd-Pb), pétrologique et géochronologique (K-Ar, Ar-Ar), de manière à identifier à la fois les sources et les processus magmatiques mis en jeu lors de leur formation. L’évolution temporelle des sources, ainsi que des processus magmatiques, a été reconstruite afin d’identifier d’éventuels liens avec l’effondrement de flanc étudié.Les résultats montrent que l’évolution du magmatisme de l’île de Fogo amène à la formation de zones superficielles de stockage, de complexes intrusifs et d’éruptions explosives conduisant à de nouvelles instabilités de l’édifice. Suite à l’effondrement, ces zones de stockage sont déstabilisées en quelques milliers d’années. Les processus magmatiques lithosphériques (assimilation, fusion partielle) sont également perturbés mais sur une période plus longue (plusieurs dizaines de milliers d’années). L’effondrement de Güímar ne montre aucun lien avec le magmatisme de l’île de Tenerife.La différence principale entre ces deux contextes est la localisation de la zone effondrée par rapport au système magmatique. En effet, l’effondrement de Güímar est situé en périphérie du système magmatique et ne montre aucun lien avec ce dernier ; à l’inverse l’effondrement du Monte Amarelo, situé à l’aplomb du système magmatique, se répercute rapidement sur ce système à faible profondeur, mais également à des profondeurs lithosphériques avec un délai plus long. / Massive flank collapses are destructive events that affect all volcanic edifices. They can take off huge volumes of rock, from tens to hundreds km3. Oceanic shield volcanoes are also affected by such events even if they have shallow slopes, thus, tsunamis could also be generated in this context. However, a shield volcano flank collapse has never been observed. Nowadays, only relics are visible, such as collapse scars, detritic deposit offshore or tsunami deposits on nearby islands. The relationships between collapse and magmatic history of oceanic shield volcanoes are poorly constrained. Two flank collapses are studied in this thesis, with the aim to better understand these relationships: the Monte Amarelo collapse, on Fogo Island (Cape Verde), and the Güímar collapse, located on North-East rift-zone of Tenerife (Canary Islands). Those archipelagos are the result of hot spot activity below the African plate. Geochemical (major and trace elements, and Sr-Nd-Pb isotopes), petrological and geochronological (K-Ar and Ar-Ar) analyses were carried out on volcanic samples as to identify the source and magmatic processes at stake during magma genesis. The temporal evolution of source and magmatic processes is reconstructed in order to track possible links with the flank collapse. The magmatic system of Fogo Island evolves through time, favouring the formation of superficial storage zones, intrusive complex and explosive eruptions prior to the collapse, which participate to the instability of the edifice. Following the Monte Amarelo collapse, shallow storage zones are destabilized within a few thousand years. Lithospheric magmatic processes (assimilation, partial melting) are also affected but on a longer timescale (tens of thousands years). The Güímar collapse shows no links with the magmatic evolution of Tenerife Island. The main difference between the two collapses is the location of the collapse area with respect to the plumbing system. Güímar collapse is located at the periphery of the plumbing system and show no link with the magmatic history. Contrariwise, the Monte Amarelo collapse is located directly above the plumbing system and influence rapidly the superficial plumbing system, and the deep plumbing system in the long term.
9

Planning behind Closed Doors: Unlocking Large-Scale Urban Development Projects Using the Stakeholder Approach on Tenerife, Spain

Hübscher, Marcus 12 June 2023 (has links)
Santa Cruz Verde 2030 is an inner-city megaproject that will transform the local oil refinery into an urban neighborhood in Santa Cruz de Tenerife, Spain. The project is expected to reconfigure Santa Cruz’s tourism model significantly, while applying rather undemocratic planning practices. This paper explores Santa Cruz Verde 2030, focusing on the perception of local stakeholders. My research builds on 18 qualitative interviews with planning authorities, the city’s mayor, political parties, experts from the real estate sector and residents. I identify a large perception gap among the interviewees. While the project’s initiators praise the participatory process, other stakeholders feel neither informed nor integrated. In particular, the “behind closed doors” planning approach has provoked resentment among citizens. In contrast, the possible impact on tourism of the project has given rise to less discussion. This contributes to the “stealthy” touristification strategy that has already transformed large areas of Santa Cruz’s waterfront in past decades. Hence, this paper adds to the ongoing discussion on how to design megaprojects in a more sustainable way, for example, by ensuring political consensus and learning from former megaprojects.
10

Megaprojects, Gentrification, and Tourism.: The Case of Santa Cruz de Tenerife (Spain)

Hübscher, Marcus 24 July 2023 (has links)
In der Neoliberalen Stadt gehören Megaprojekte zu den sichtbarsten städtebaulichen Elementen. Sie sind Ausdruck eines ständigen Wettbewerbs städtischer Räume um Ressourcen, Kapital und die Stellung in der globalen urbanen Hierarchie. Gleichzeitig stehen die Projekte in der Kritik, undemokratische Planungsstrukturen und räumliche Ungerechtigkeiten zu verfestigen. Touristifizierungs- und Gentrifizierungsprozesse gehören zu den möglichen Folgen von Megaprojekten – nicht nur auf der betreffenden Fläche selbst, sondern auch in umliegenden Quartieren. Ziel dieser Arbeit ist die Erforschung des Zusammenspiels von Megaprojekten, Gentrification und Tourismus am Fallbeispiel Santa Cruz Verde 2030. Das innerstädtische Projekt transformiert die Erdölraffinerie im Zentrum der Stadt Santa Cruz de Tenerife (Spanien) in ein nutzungsgemischtes und urbanes Quartier. Es wird der Frage nachgegangen, inwiefern das Megaprojekt in bestehende Raum- und Funktionsbezüge eingreift und welche Stakeholder bei der Planung des Vorhabens (nicht) integriert sind. Diesem Untersuchungsgegenstand nähert sich die Dissertation unter Einbezug von quantitativen und qualitativen Forschungsmethoden. Hierzu zählen ein systematischer Literature Review, eine multivariate Vulnerabilitäts- und Clusteranalyse sozialräumlicher Daten, geographische Informationssysteme sowie qualitative Interviews. Als theoretische Rahmung bedient sich diese Forschungsarbeit der räumlichen Gerechtigkeit (spatial justice). Dabei werden Polarisierungen zwischen primären und sekundären Stakeholdern sowie vulnerablen und nicht-vulnerablen Sozialräumen herausgearbeitet. Die Arbeit zeigt, wie Konzept und Planung von Santa Cruz Verde 2030 auf bestimmte Zielgruppen fokussiert sind, während lokale Bewohner:innen ausgeschlossen werden. Gleichzeitig sind infolge des Megaprojektes Touristifizierungs- und Gentrifizierungsprozesse in Santa Cruz zu erwarten. Die somit reproduzierten Ungerechtigkeiten könnten durch transparente Planungsverfahren und Beteiligung abgeschwächt werden – weshalb die Arbeit ein Aufbrechen der etablierten Entscheidungs- und Handlungspraktiken in neoliberal geprägten Städten fordert.:1. Einleitung 2. Megaprojects, Gentrification, and Tourism 3. From one Crisis to Another 4. The Impact of Airbnb on a Non-Touristic City 5. Zwischen Deindustrialisierung und Gentrification 6. From Megaprojects to Tourism Gentrification? 7. Opaque Urban Planning 8. Planning behind closed Doors 9. Schlussbetrachtung / Inner-city megaprojects are very visible elements in neoliberal urbanism. Such projects are regarded as a symbol of the ongoing competition between urban spaces and the fight over resources, wealth, and a higher position in the global urban hierarchy. Simultaneously, megaprojects are criticized for reinforcing undemocratic planning structures and spatial injustices. Thus, touristification and gentrification are often observed impacts – not only at the project’s site but also in surrounding neighborhoods. The objective of this doctoral thesis is to explore the relationship between megaprojects, gentrification, and tourism, using Santa Cruz Verde 2030 as a case study. This megaproject aims to transform the inner-city oil refinery in Santa Cruz de Tenerife (Spain) into a mixed-use urban neighborhood. In this thesis, I will investigate to what extent the megaproject will (not) interfere with existing spatial and functional relationships, and which stakeholders have (not) been integrated into the wider process. In order to appraise this megaproject ex-ante, a mix of quantitative and qualitative methods is proposed (such as a systematic literature review, a multivariate vulnerability and cluster analysis of socio-spatial data, geographic information systems, and qualitative interviews). Using spatial justice as a lense, I will show the highly polarized social and urban setting of the future megaproject. Apart from that, the concept and planning of the project are strongly focused on specific target groups, while local residents are excluded. At the same time, Santa Cruz Verde 2030 is expected to cause touristification and gentrification. This will reproduce spatial injustices in the city that could be mitigated through transparent planning procedures and participation – which is why this thesis demands to rethink the established decision-making in the neoliberal city.:1. Einleitung 2. Megaprojects, Gentrification, and Tourism 3. From one Crisis to Another 4. The Impact of Airbnb on a Non-Touristic City 5. Zwischen Deindustrialisierung und Gentrification 6. From Megaprojects to Tourism Gentrification? 7. Opaque Urban Planning 8. Planning behind closed Doors 9. Schlussbetrachtung

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