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La incidencia de los mapas en la producción social de espacios en la región de Aysén entre los siglos XIX-XXIUribe Rivas, Felipe January 2018 (has links)
Memoria para optar al título de Geógrafo / En la presente investigación se estudia la producción social de espacios en la Región de Aysén desde una perspectiva cartográfica, durante el periodo que abarca desde el siglo XIX hasta el presente. La finalidad de este estudio es indagar si los mapas, en distintos periodos del tiempo, han influido de alguna forma en la producción social de espacios de esta región. Metodológicamente, este trabajo responde principalmente a una investigación de carácter cualitativa, la cual se desarrolló mediante un análisis de mapas desde un enfoque hermenéutico y un análisis contextual-descriptivo de estos de acuerdo a los períodos definidos en la investigación, con la finalidad de identificar y definir discursos cartográficos e imaginarios geográficos. Respecto a los resultados obtenidos, estos han permitido establecer que los mapas pueden y han sido utilizados como estrategias de producción social de espacios cuando han sido elaborados con la finalidad de instaurar una mirada o perspectiva determinada del territorio. Por lo que a partir del análisis interpretativo de mapas se ha logrado revelar una nueva forma de entender los procesos constitutivos de los espacios, permitiendo al mismo tiempo entender, proponer, reafirmar y complementar ciertas percepciones y discursos sobre el territorio de Patagonia-Aysén. / In the present investigation the social production of spaces in the Region of Aysén and Patagonia is studied from a cartographic perspective, during the period from the 19th century to the present. The purpose of this study is to investigate if the cartographic production, in different periods of time, has influenced in some way the conformation of the social space of Patagonia-Aysén. For its realization, a qualitative methodology was used, which consists in the analysis of maps from a hermeneutic approach and a contextual-descriptive analysis in relation to the periods defined in the investigation, with the purpose of identifying and defining cartographic discourses and geographical imaginaries. Regarding the results obtained, these have allowed to establish that the maps can and have been used as strategies of social production of spaces when they have been elaborated with the purpose of establishing a perspective or determined perspective of the territory. So from the interpretative analysis of maps it has been possible to reveal a new way of understanding the constitutive processes of the spaces, allowing at the same time to understand, propose, reaffirm and complement certain perceptions and discourses about the Patagonia-Aysén territory.
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Glacier response to climate variability and climate change across the Southern AndesWeidemann, Stephanie Suzanne 16 June 2021 (has links)
Die Gletscherschmelze in den südlichen Anden trägt maßgeblich zum Anstieg des Meeresspiegels der letzten Jahrzehnte bei und beeinflusst regional die saisonale Wasserverfügbarkeit. In jüngster Zeit wurde eine rapide Zunahme der Massenverluste insbesondere einzelner großer Auslassgletscher des Südlichen Patagonisches Eisfeldes beobachtet. Im Rahmen der Dissertation wurden die rezente Variabilität des Klimas und der klimatischen Massenbilanz für ausgewählte vergletscherte Gebiete in Patagonien und Feuerland untersucht. Die Verbesserung unseres Verständnisses über räumliche und zeitliche Muster der klimatischen Massenbilanz, ihrer atmosphärischen Antriebsfaktoren und ihres Einflusses auf das in jüngster Vergangenheit beobachtete individuelle Gletscherverhalten, sind weitere wichtige Ziele. Da die Klimavariabilität die Hauptursache für lokale Veränderungen in der Kryosphäre der südlichen Anden ist, wurden langjährige meteorologische Beobachtungen im Gebiet der Gran Campo Nevado-Eiskappe im südlichsten Patagonien im Hinblick auf räumliche und zeitliche Variabilität untersucht und der Einfluss mesoskaliger Wettermuster und Modi atmosphärischer Oszillationen auf die Ausprägung des Klimas analysiert. Darüber hinaus wurde die rezente Variabilität der klimatischen Massenbilanz für ausgewählte Gletscher in Südpatagonien und Feuerland durch die Implementierung des Energie- und Massenbilanzmodells COSIMA simuliert. Eine unterschiedliche Ausprägung der Oberflächenmassenbilanz und geodätischer Massenbilanz unterstreicht wie wichtig ein besseres Verständnis über die Prozesse der klimatischen Massenbilanz und Eisdynamik ist. Des Weiteren wurden Simulationen der klimatischen Massenbilanz eingesetzt, um eine ausgeglichene Massenbilanz für rezente und vergangene Ausdehnungen des Gletschers Schiaparelli abzuleiten. Ziel war es, eine modellgestützte Annäherung an die klimatischen Bedingungen während der Kleinen Eiszeit zu simulieren. / Glacier mass loss of the Southern Andes contributes largely to sea-level rise during recent decades and also affects the regional water availability. Despite the overall glacier retreat of most glaciers in Patagonia and Tierra del Fuego, a recent increase in mass loss of individual glaciers has been observed. The recent variability of climate and climatic mass balance for selected glaciated study sites in Patagonia and Tierra del Fuego are investigated in this thesis. Improving our understanding on the spatial and temporal variations of climatic mass balance processes, its atmospheric drivers, and their impact on the recently observed individual glacier behavior are further important aims.
Since climate variability is the key driver of local changes in the cryosphere in the Southern Andes, a unique record of meteorological observations across the Gran Campo Nevado Ice Cap in Southernmost Patagonia was analyzed with regard to main climate features and the relationship between the in-situ observations, large-scale climate modes and mesoscale weather patterns.
Furthermore, recent climatic mass balance variability was simulated for selected glaciers in Southern Patagonia and Tierra del Fuego by implementing the ’COupled Snow and Ice energy and MAss balance model’ COSIMA. Contrasting patterns of positive simulated annual climatic mass balance and clearly negative geodetic mass balance were found for two neighboring glaciers of the Southern Patagonia Icefield between 2000 and 2014. This highlights the importance of understanding of both, the climatic mass balance, and the ice-dynamical processes. Climatic mass balance simulations were further used to derive glacier steady-state conditions for recent and past glacier extents of Schiaparelli Glacier, aiming for a model-based approximation of climate conditions during the Little Ice Age.
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A Human-Centered Approach to Designing an Invasive Species Eradication ProgramSanto, Anna Ruth 22 May 2015 (has links)
The increasing scope and speed of biological invasions around the world is a major concern of the modern environmental conservation movement. Although many ecological impacts of biological invasions are still not well understood, there is a general consensus that exotic, invasive species are a primary driver of extinctions globally. By altering ecosystem structure and function, invasive species also affect human quality of life; however, not all impacts lead to negative outcomes.
Given that invasive species have diverse impacts on society, their management in human-dominated landscapes is a wicked problem wherein the resolution is as much an issue of social value as technical capacity. The purpose of my research was to understand the propensity for engaging private landowners in an effort to eradicate an invasive species on an inhabited island. Specifically, I investigated private landowner perspectives on eradicating the North American beaver (Castor canadensis) from the Tierra del Fuego (TDF) island archipelago in Argentina and Chile. The beaver was introduced in 1946 and has since become a central conservation issue due to its long-lasting changes to local hydrology, nutrient cycling, riparian vegetation, food webs, and aquatic and terrestrial species assemblages.
Because eradication requires near complete cooperation from stakeholders and no research had been conducted to understand the perspectives or willingness of private landowners to cooperate, my objectives were to: 1) characterize the links private landowners make between the presence of beavers and impacts to the ecosystem services in their riparian areas, and 2) explore the role of a market-based incentive program to increase landowner cooperation in eradication efforts.
Through semi-structured interviews, I elicited landowner mental models of how beavers impact the ecosystem services they receive from their riparian lands. I found that TDF ranchers prioritized provisioning ecosystem services, and held diverse and idiosyncratic beliefs about how beavers influence these outcomes. TDF ranchers may not recognize the beaver as a highly salient problem because they do not connect them to reductions in ecosystem services that are important to them. Among those who do perceive beavers affecting important ecosystem services, there is no clear, unified understanding of how the beavers disturb the ecosystem and key ecosystem services.
Additionally, in a broadly administered survey, I used a factorial vignettes to examine the role of program structure and other program-related factors on landowners' willingness to participate in a voluntary eradication program. Overall, landowners were willing to cooperate in an incentive program to eradicate beavers. They were positively motivated by greater financial compensation, an increased expectation that the program would be successful, and the program assuming full responsibility for its implementation. Other factors returned mixed results indicating that further research may be required.
In diverse, human-inhabited, and privately-owned landscapes, conservation requires collective action—i.e., the high threshold of participation needed for eradication to be achieved. Understanding the knowledge systems that cause landowners to perceive value or risk serves as a first step in understanding behaviors, and can also serve as a framework for crafting more effective outreach, as current communication about the beaver and the proposed eradication may not resonate with private landowners. Further, barriers to inaction can be overcome by understanding landowner needs and how program-related factors influence the potential for cooperation.
In sum, by putting human needs at the forefront of program design, conservation planners can better understand stakeholder perspectives, reduce barriers to participation, and ultimately increase cooperation and improve conservation outcomes. / Master of Science
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Végétation et climat de la Patagonie chilienne au cours des derniers 20 000 ans d’après les données polliniques marines / Vegetation and climate of chilean Patagonia during the last 20, 000 years from marine pollen dataMontade, Vincent 12 December 2011 (has links)
Dans le contexte du réchauffement climatique, les enregistrements paléoclimatiques à différentes échelles temporelles et spatiales apparaissent essentiels pour comprendre les mécanismes du climat. La Patagonie Chilienne (41°S à 56°S) parcourue du Nord au Sud par les Andes représente une contrainte topographique majeure sur les circulations atmosphériques et océaniques. Cette région est la seule qui intercepte la totalité de la ceinture des vents d'ouest austraux et constitue donc une zone clé pour étudier les changements paléoenvironnementaux et comprendre les mécanismes océan-atmosphère et leurs interactions aux moyennes et hautes latitudes de l'hémisphère sud. Dans ce contexte, les objectifs de cette thèse sont : (1) de tester l’analyse pollinique dans les sédiments marins de cette région, (2) d’étudier les modifications des paléoenvironnements continentaux au cours des 20 000 dernières années à partir de deux carottes océaniques de la campagne "PACHIDERME" (MD07-3088 et MD07-3104) et (3) de déterminer leurs liens avec l’activité des vents d’ouest et avec l’influence de ces vents dans l’hémisphère sud et donc sur le climat à l’échelle globale. Les analyses polliniques dans les sédiments marins de surface à l’intérieur et à l’extérieur des fjords de la Patagonie reflètent fidèlement la végétation actuelle développée sur le continent le plus proche, ce qui prouve la validité de la palynologie marine dans cette région. Au niveau de la péninsule de Taitao (46°S), l’expansion des forêts nord patagoniennes après 17.6 ka marque le début de la déglaciation. Cette dernière est interrompue par un évènement froid et humide, l’Antarctic Cold Reversal (ACR) qui s’exprime ici par le développement des tourbières de Magellan et est lié à l’intensification des vents d’ouest. Le développement de taxons héliophiles à ~11 ka illustre le début de l’Holocène sous des conditions plus chaudes et plus sèches qui sont également enregistrées autour du Fjord de Reloncavi (41°S). Ces conditions persistent jusqu’à ~8-7 ka, puis les changements de végétation aux cours de l’Holocène montrent une variabilité climatique plus importante évoluant vers un climat plus froid et plus humide qui se renforce au nord de la Patagonie après ~6-5 ka puis pendant l’Holocène supérieur. La comparaison de nos résultats avec les données paléoclimatiques de la région souligne les déplacements de la ceinture des vents d’ouest. Après une descente rapide vers le sud au début de la déglaciation, cette ceinture des vents d’ouest remonte vers le nord pendant l’ACR avant de redescendre à nouveau vers le sud à l’Holocène proche de sa position actuelle. Ce phénomène appuie l’hypothèse d’un lien entre les variations du CO2 atmosphérique et la ceinture des vents d’ouest jusqu’au début de l’Holocène. A partir de l’Holocène moyen et supérieur, la ceinture des vents d’ouest s’élargit avec un léger retour vers le nord probablement lié à la mise en place d’El Niño au niveau de l’océan Pacifique tropical. / In the context of global warming, paleoclimate records at different time and spatial scales appear critical to understand climate mechanisms. Chilean Patagonia (41°S to 56°S), crossed by the Andes from north to south, represents a major topographic constraint on ocean and atmospheric circulation. It is the only region that intercepts the entire southern westerly wind belt. Thus it represents a key-area for the study of paleoenvironmental changes in the southern hemisphere and the understanding of ocean-atmosphere mechanisms and their interactions from the mid- to high-latitudes of the southern hemisphere. In this context, the purposes are: (1) to test the pollen analysis on marine surface sediments in this region, (2) to study the continental changes of paleoenvironments during the last 20,000 years from two oceanic cores of the "PACHIDERME" campaign (MD07-3088 and MD07-3104) and (3) to evaluate their links with southern westerly wind belt activity and with the influence of these winds on the southern hemisphere and with the climate at a global scale. The pollen analyses of marine surface sediments in fjords or offshore from Chilean Patagonia reflect the present-day vegetation from the nearby continental area. At the Peninsula of Taitao (46°S), the North Patagonian forest expansion after 17.6 kyr shows the beginning of the deglaciation. This last (period) is interrupted by a wet and cool event, the Antarctic Cold Reversal (ACR), that was expressed here by development of the Magellanic moorland linked to the southern westerly wind intensification. The expansion of heliophytic taxa at ~11 kyr illustrates the beginning of the Holocene under warmer and drier conditions that are also recorded around the fjord of Reloncavi (41°S). These conditions persisted until ~8-7 kyr, and then the vegetation changes during the Holocene show a larger climate variability toward a cooler and wetter climate that enhances in northern Patagonia later ~6-5 kyr during the Late Holocene. Our results compared with the regional paleoclimatic data highlight the shifts of the southern westerly wind belt. After a rapid southward shift at the beginning of the deglaciation, the southern westerly wind belt returns northward during the ACR before reaching southern latitudes near to their present-day position. This scheme strengthens the inference of the link between atmospheric CO2 variability and the southern westerly wind belt up to the Early Holocene. From the mid and late Holocene, the southern westerly wind belt was displaced northward with a slight return probably linked to the beginning of El Niño recorded in tropical Pacific Ocean.
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Taxonomie, Paläoökologie und Paläobiodiversitätsdynamik benthischer Mollusken an der Kreide-Paläogen-Grenze von PatagonienWeidemeyer, Sven 14 December 2009 (has links)
Aus Patagonien lagen bisher wenige Daten zu paläoökologischen Veränderungen und zur Paläobiodiversität an der Kreide-Paläogen (K/Pg)-Grenze vor. Um diese Lücke zu schließen, wurden in den argentinischen Provinzen Neuquén und Chubut zahlreiche Profile im Bereich der K/Pg-Grenze detailliert beprobt. Während einer Planktonkrise, wie sie für die K/Pg-Grenze angenommen wird, werden für benthische Mollusken folgende Entwicklungen erwartet: 1. eine Abnahme der Individuenzahlen der Benthosorganismen, 2. eine Abnahme der vom Plankton als Nahrungsquelle direkt abhängigen Organismen, 3. eine Abnahme der Benthonten mit planktotrophen Larvalstadien, 4. eine Abnahme der mittleren Körpergröße der Individuen benthischer Faunengemeinschaften und 5. eine Abnahme der Organismen mit hoher Stoffwechselrate bzw. aktiver, mobiler Lebensweise. Tatsächlich waren die hungerresistenten Gruppen der Nuculoida (flach-infaunale Depositfresser) und der Lucinidae (Chemosymbionten) im Danium signifikant häufiger als im Maastrichtium, während der Faunenanteil der Suspensionsfresser im Danium im Vergleich zum Maastrichtium signifikant niedriger ist. In den Faunengemeinschaften des Daniums von Bajo de Añelo konnten Abnahmen der Individuenzahlen, der mittleren Mobilität und der mittleren Größe festgestellt werden. Die beobachteten paläoökologischen Veränderungen zeigen somit eine Selektivität, die sich auch in der Paläobiodiversitätsdynamik widerspiegelt. Auch hier sind Suspensionsfresser, die direkt vom Planktonangebot abhängig sind, stärker betroffen als Chemosymbionten und flach-infaunale Depositfresser. Die Aussterberaten für Bivalven sind mit 28% moderat. Insgesamt sind die festgestellten Selektivitätsmuster konsistent mit den zu erwartenden Folgen einer Planktonkrise. Trotz einiger regionaler Unterschiede handelte es sich um ein globales Ereignis an der K/Pg-Grenze, das Nord- und Südhalbkugel gleichermaßen betroffen hat. / From Patagonia only a few data on palaeoecological changes and on palaeobiodiversity at the Cretaceous/Paleogene (K/Pg)-boundary are available so far. Therefore detailed samples in different K/Pg-sections in the Argentinian provinces of Neuquén and Chubut were taken to increase the data set for this region. The following trends are expected from a crisis of primary productivity in the aftermath of the K/Pg-boundary: 1. a reduction in the number of individuals of benthic organisms, 2. a decrease in the relative abundance of organisms which rely directly on photosynthesis, 3. a lower proportion of individuals with planktotrophic larval stages, 4. a reduction in the average body size of individuals within palaeocommunities and 5. an increased abundance of organisms with low metabolic rates or inactive lifestyles. In fact the proportion of the starvation-resistant groups of the Nuculoida (shallow-infaunal deposit feeders) and Lucinidae (chemosymbionts) were significantly higher in the Danian compared to the Maastrichtian. In contrast to this, the proportion of suspension feeders in the palaeocommunities was significantly lower in the Danian in comparison with the Maastrichtian. In the Danian benthic assemblages of the Bajo de Añelo area, a decrease in number of individuals, mean mobility and mean size was recognised after the K/Pg-boundary. Thus the palaeoecological changes display a selectivity, which is also reflected in the palaeobiodiversity. Suspension feeders, which depend directly on plankton particles from the water column, show higher extinction rates than chemosymbionts and shallow-infaunal deposit feeders. The extinction rates of Patagonian bivalves are moderate (28%). Overall, the recognized selectivity patterns are consistent with the expected aftermath of a crisis in primary productivity. Despite some local differences, the results argue for a global event at the K/Pg-boundary during which the northern and southern hemispheres were similarly affected.
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Die neogene Hebungsgeschichte der Patagonischen Anden im Kontext der Subduktion eines aktiven SpreizungszentrumsWarkus, Frank January 2002 (has links)
Das Phänomen der Subduktion eines aktiven Spreizungszentrums an der Südspitze Südamerikas ist seit langem bekannt. Eine Vielzahl von geologischen Beobachtungen wurden mit diesem Phänomen in Verbindung gebracht, trotzdem ist der genaue Mechanismus der Beeinflussung des aktiven Kontinentalrandes weitgehend unbekannt. <br />
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Die Zusammenhänge zwischen den Subduktionsprozessen und der Entwicklung der patagonischen Anden zwischen 47°S und 48°S stehen im Mittelpunkt der Untersuchungen. Um eine detaillierte zeitliche Auflösung der zugrunde liegenden Prozesse untersuchen zu können, wurde die Entwicklung der Vorlandsedimentation, die thermische Entwicklung und die Heraushebung der Oberkruste des andinen Orogens untersucht und diese in Bezug zur Subduktion des Chile-Rückens gesetzt. <br />
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Im Bereich von 47°30′S wurden die synorogenen Vorlandsedimente der Santa Cruz Formation sedimentologisch untersucht. Diese fluviatilen Sedimente wurden in einem reliefarmen Vorlandgebiet durch häufige Rinnenverlagerung und dem Aufbau von Rinnenumlagerungsgürteln in Kombination mit assoziierten großräumigen Überflutungsablagerungen akkumuliert. Sie stehen in einem engen Zusammenhang mit der orogenen Entwicklung im andinen Liefergebiet. Dies spiegelt sich in dem nach oben gröber werdenden Zyklus der Santa Cruz Formation wider. Die magnetostratigraphischen Untersuchungen einer 270 m mächtigen Sequenz aus der Basis der Santa Cruz Formation, die mit 329 Einzelproben aus 96 Probenpunkten beprobt wurde, ergab 7 Umkehrungen der geomagnetischen Feldrichtung. Mit Hilfe der geomagnetischen Polaritätszeitskala (CANDE AND KENT, 1995) konnte der untersuchte Abschnitt der Santa Cruz Formation zwischen 16.2 und 18.5 Ma datiert werden. Als Träger der Sedimentations-Remanenz konnten überwiegend Pseudoeinbereichs-Magentitpartikel und untergeordnet Hämatitpartikel identifiziert werden. <br />
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An drei Profilen der Santa Cruz Formation wurden aus Sandsteinlagen unterschiedlicher stratigraphischer Position detritische Apatite mit Hilfe der thermochronologischen Spaltspurmethode untersucht. Die thermisch nicht rückgesetzten, detritischen Apatite spiegeln das Auftreten unterschiedlicher Altersdomänen im Liefergebiet der Sedimente wider. In der Kombination mit den geochemischen Gesamtgesteinsuntersuchungen der Sedimente und den petrographischen Untersuchungen der Sandsteine, die ein überwiegend andesitisch-vulkanisch geprägtes Liefergebiet widerspiegeln, kann nachgewiesen werden, dass die Erosion im Liefergebiet um 16.5 Ma in tiefere, deformierte Krustensegmente einschneidet. Dies bedeutet, dass aufgrund der Denudation im andinen Orogen erste Sockelgesteinseinheiten in den Bereich der Abtragung gelangen und dass dieser Eintrag um 12 bis 10 Ma ein Volumen einnimmt, das zu signifikanten Änderungen der Gesamtgesteinsgeochemie der Vorlandsedimente führt. <br />
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Die thermochronologische Untersuchung von Apatiten aus rezenten topographischen Höhenprofilen aus der Kernzone der patagonischen Anden im Bereich von 47°30′S zeigen den Beginn einer beschleunigten Heraushebung des Orogens um 7.5 Ma. Aus diesen Untersuchungen kann eine Denudationsrate im Zeitraum der letzen 7 bis 8 Ma von 600 bis 650 m/Ma abgeschätzt werden. Die Modellierung der Apatit-Spaltspurergebnisse zeigt eine signifikante Temperaturerhöhung im Zeitraum zwischen 12 und 8 Ma um 20 bis 30°C für diesen Krustenbereich, die mit der Subduktion des aktiven Chile-Rückens in diesem Bereich der Anden in Verbindung gebracht wird. <br />
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Aus den gewonnen Daten kann ein Modell für die Entwicklung der patagonischen Anden seit dem frühen Miozän abgeleitet werden. In diesem Modell wird die orogene Entwicklung in den patagonischen Anden auf eine erhöhte Konvergenzrate zwischen der Nazca Platte und der Südamerikanischen Platte zurückgeführt, die für die Heraushebung und Denudation der Anden sowie für die damit verbundene Entwicklung im Vorlandbereich verantwortlich ist. Diese orogene Entwicklung wird in einer späten Phase durch die nordwärts wandernde Subduktion des aktiven Spreizungszentrums des Chile Rückens überprägt und beeinflusst. Das auf der Integration von geologischen, chronologischen sowie thermochronologischen Daten beruhende Modell kann zahlreiche geologische und geophysikalische Beobachtungen in diesem Bereich der südlichen Anden konsistent erklären. / The phenomenon of active ridge subduction to the continental margin of southern South America has been well known for a long time. A diversity of geological observations are related to this phenomenon, however, the exact mechanism of the influence of ridge subduction to the active continental margin is unknown.<br />
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The aim of the present investigations is to determine connections between the subduction processes and the development of the Patagonian Andes between 47°S and 48°S. In order to reach that objective, the development of the foreland basin settings, the uplift of the upper crust of the Andean Orogeny, and the relation with the subduction of the Chile Ridge were investigated to obtain a detailed temporal resolution of the basic geological processes.<br />
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Within the area of 47°30'S the style and sedimentological pattern of the synorogenic foreland deposits of the Santa Cruz Formation were investigated. These fluvial sediments were accumulated in a foreland basin of small scale topography by frequent progradational avulsions, which were accompanied by deposition of avulsion-belt sediments associated with thick overbank deposits. <br />
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The upward-coarsening is best explained by progradation of fan deposits during an eastwards advancement of the deformation in the western Andes at that time. <br />
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Magnetostratigraphic investigations of a total of 329 drill cores, which were collected at 96 sites, show seven major reversals in a thick stratigraphic section of 270 m from the base of the Santa Cruz Formation. A comparison with the geomagnetic polarity timescale of Cande and Kent (1995) gives a sedimentation age between 16.2 and 18.5 Ma for the investigated section of the Santa Cruz Formation. The investigation of rock-magnetism predominantly indicates magnetite and subordinated haematite as the dominant carrier of remanence. All results from hysteresis data determination cluster in the coarse pseudo-single (PSD) to multi-domain (MD) grain size range of the Day Diagram (DAY ET AL. 1977)<br />
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Fission track analysis was applied to detrital apatite of sandstone samples at different stratigraphic positions within three sections of the Santa Cruz Formation. The fission track ages of the not reseted detrital apatite are assumed to be related to the age of the sediment provenance area. In combination with sandstone petrographic investigations, which indicate a dominant andesitic volcanic source for the sediment and geochemical whole rock investigations can be shown, that the erosion cuts into the basement of the source area at 16.5 Ma. This means, that due to the denudation in the Andean Orogen first deformed basement units arrive into the sedimentation cycle. In the range of 12 to 10 Ma this sediment input attained such a volume, that the whole-rock geochemistry of the sediments was changed .<br />
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The thermochronological investigations of apatites from vertical profiles covering the largest elevation range of the central zone of the Patagonian Andes within the range of 47°30'S show the beginning of an accelerated cooling and related uplift phase of the orogen at approximately 7.5 Ma. The calculated denudation rate in the period of the last 7 to 8 Ma ranges from 600 to 650 m/Ma. The modelling of apatite fission-track data shows a significant reheating in the range of 20 to 30°C between 12 and 8 Ma for the upper crust. This is interpreted as an influence of the active Chile rise mid-oceanic spreading center on the overriding plate.<br />
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The modelling of the apatite fission-track results shows a significant rise in temperature between 12 and 8 Ma around 20 to 30°C for this crust area, which is associated with the subduction of the active Chile back in this area of the Andes. <br />
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A model has been derived from the obtained data to explain the evolution of the Patagonian Andes since the early Miocene. In this model, orogeny is attributed to the increasing convergence rate between the Nazca plate and South America and its response due to uplift and denudation of the Patagonian Andes and the development of the adjacent foreland basin. In a late phase, orogeny is influenced and overprinted by the northward migration of the Chile ridge subduction. The model consistently explains many of the geological and geophysical observations.
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A batalha pela Patagônia Chilena : o processo de formulação e operação das críticas ao projeto hidrelétrico "HidroAysén" e a construção de um conflito ambientalAranda, Yara Paulina Cerpa January 2014 (has links)
Esta pesquisa analisa o processo de constituição do conflito ambiental em torno ao Projeto Hidrelétrico HidroAysén (PHA), proposto para Região de Aysén, Patagônia chilena. O consórcio conformado em 2006 pela empresa hispano-italiana, ENDESA (51%) e a chilena Colbún (49%), propõe a construção de um complexo hidrelétrico de cinco represas nos rios Baker e Pascua. Desde seu anúncio, o projeto foi alvo de controvérsia quanto aos possíveis impactos e denúncias de falências no estudo de impacto ambiental. Sob a reivindicação de uma “Patagônia Sem Represas”, um amplo movimento opositor ao PHA organizou-se impulsionando o debate, impedindo o andamento do empreendimento por via judicial e obtendo um relativo sucesso em termos de repercussão e adesão à “causa”. Neste cenário, o objetivo geral do estudo é compreender de que forma uma demanda transcende o local para se tornar uma demanda nacional. Deste modo, a partir da perspectiva teórica-epistemológica de Luc Boltanski (2010) e colaboradores articulada à síntese construcionista de John Hannigan (2009) investigam-se as ações e mobilizações coletivas e individuais contrárias ao PHA. Para tanto, priorizou-se decompor o fio das ações, identificando os agentes engajados (conservacionistas, produtores rurais, ONG’s, entre outros), apresentando a experiência negociada na convergência de um interesse em comum e evidenciando os objetos em que estes se apóiam para formular e referendar a validade de suas argumentações. A pesquisa de campo foi realizada entre maio e agosto de 2013, em Santiago do Chile e em quatro localidades adjacentes ao projeto em Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins, utilizando-se uma combinação de procedimentos qualitativos, como: observação, entrevistas narrativas episódicas de Flick (2008), fotografia, pesquisa documental e diário de campo. Como resultado, observou-se que as competências emergem de três situações: 1) da necessidade de instaurar a Patagônia como um bem comum por meio de uma qualificação ambiental das justificativas, colocando-a sistematicamente como algo importante para as futuras gerações; 2) das percepções quanto ao PHA, onde se destaca a disputa sobre quem são os “atingidos”; 3) e do embate entre o que é planejado localmente e o que é imposto sob égide do “desenvolvimento”. O estudo de tais competências permitiu caracterizar a tendência das ordens de justificação evocadas pelos agentes contrários ao PHA em críticas: a) ambiental e estética; b) ambiental e social; c) críticas às práticas da empresa ao modelo desenvolvimento. Por outro lado, apresentam-se as justificativas acionadas pelo ente criticado e pelo pólo favorável ao PHA: a) projeto país; b) desenvolvimento e progresso regional e nacional; e c) críticas ao ambientalismo. Por fim, averiguou-se a existência de todos os elementos necessários para a construção bem sucedida de um problema ambiental conforme os fatores elencados por Hannigan (2009). Contudo, considerou-se precipitado afirmar que a presença destes elementos são as condicionantes que tornam este conflito excepcional, ficando o indicativo da importância da realização de futuros estudos em perspectiva comparada de conflitos ambientais para maiores inferências. / This research analyses the process of formation of the conflict over environmental issues surrounding the establishment of the HidroAysén Hydropower Plant (PHA), approved for the Aysén Region, located at Chilean Patagonia. A joint venture formed in 2006 between the binational (Spanish and Italian investiment) ENDESA (51%) and the Chilean Colbún (49%), aims to build a complex of five hydroelectric power plants located in the Baker and Pascua Rivers. Since its oficial announcement, the Project has arisen intense controversy in what regards both its demages to the environment, and the probity on the issuing of enviroment certifications. An active movement of resistance has convened around the so called “Patagonia Sin Represas” (“Patagonia without dams”), providing momentum to the public debate against the PHA and obtaining favorable judicial pronouncements to obliterate the construction of the dam. This has resulted in an increase on the morale of the cause against the PHA. Against this scenario, this research aimed at comprehending in what ways do a local demand transcends the local dimension and turn into a broader demand, echoing in the breader national sphere. For that purpose, this research draws on Luc Boltanski (2010) theoretical and epistemological contribution, as well as on the constructionist synthesis as ellaborated by John Hannigan to investigate the collective and individual mobilization and actions taken against the PHA. A priority was given to the decomposition of the tread of actions taken, identifying the actors engaged (enviromenmentalists, land owners, NGO’s, etc.), in order to clarify the negotiation contained in the phenomena and the objects in which the parties rely on in the search to validate their positions. The research field has been effectuated in 2013, between may and august, in Santiago and in other four different locations adjacent to the projects Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins. There has been employed a combination of a certain number of qualitative methods for data collection: direct observation, Flick’s (2008) episodic narratives interview, photography, research on documents and notes taken in field diaries. As a result, there has been possible to observe that certain competences emerge within three given situations: 1) the necessity to instate Patagonia as common good through means of qualification of the environmental rhetoric, placing it as importante for future generations; 2) perceptions of the PHA, in especial regards to those deemed directly “affected by the dam”, and 3) the disputes between that which is planned locally and that, otherwise, is imposed under the áuspices of the “development”. The study of those competencies allowed for characterizing the tendencies in the order of justification by the critics of the PHA: a) environmental and esthetical; b) environmental and social; and c) critical to the practices assumed by the joint venture, responsible for the PHA, in terms of the present paradigm of development. On the other hand, the research also presents the arguments for the justification posed by the part being criticized, the PHA supporters and its advocates: a) project of Nation; b) development and regional and national progress; c) criticism to the environmentalist. All the elements enumerated by Hannigan (2009), and deemed as necessary for the establishment of a well succeeded environmental agenda, were detected in this research. Nevertheless, it’s been considered still early to draw affirmative conclusions as to whether the presence of these elements are a condition for the exceptionality of the conflict. Notwithstanding, this remains as an indication of the importance for the realization of future comparative studies in the same realm of research.
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A batalha pela Patagônia Chilena : o processo de formulação e operação das críticas ao projeto hidrelétrico "HidroAysén" e a construção de um conflito ambientalAranda, Yara Paulina Cerpa January 2014 (has links)
Esta pesquisa analisa o processo de constituição do conflito ambiental em torno ao Projeto Hidrelétrico HidroAysén (PHA), proposto para Região de Aysén, Patagônia chilena. O consórcio conformado em 2006 pela empresa hispano-italiana, ENDESA (51%) e a chilena Colbún (49%), propõe a construção de um complexo hidrelétrico de cinco represas nos rios Baker e Pascua. Desde seu anúncio, o projeto foi alvo de controvérsia quanto aos possíveis impactos e denúncias de falências no estudo de impacto ambiental. Sob a reivindicação de uma “Patagônia Sem Represas”, um amplo movimento opositor ao PHA organizou-se impulsionando o debate, impedindo o andamento do empreendimento por via judicial e obtendo um relativo sucesso em termos de repercussão e adesão à “causa”. Neste cenário, o objetivo geral do estudo é compreender de que forma uma demanda transcende o local para se tornar uma demanda nacional. Deste modo, a partir da perspectiva teórica-epistemológica de Luc Boltanski (2010) e colaboradores articulada à síntese construcionista de John Hannigan (2009) investigam-se as ações e mobilizações coletivas e individuais contrárias ao PHA. Para tanto, priorizou-se decompor o fio das ações, identificando os agentes engajados (conservacionistas, produtores rurais, ONG’s, entre outros), apresentando a experiência negociada na convergência de um interesse em comum e evidenciando os objetos em que estes se apóiam para formular e referendar a validade de suas argumentações. A pesquisa de campo foi realizada entre maio e agosto de 2013, em Santiago do Chile e em quatro localidades adjacentes ao projeto em Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins, utilizando-se uma combinação de procedimentos qualitativos, como: observação, entrevistas narrativas episódicas de Flick (2008), fotografia, pesquisa documental e diário de campo. Como resultado, observou-se que as competências emergem de três situações: 1) da necessidade de instaurar a Patagônia como um bem comum por meio de uma qualificação ambiental das justificativas, colocando-a sistematicamente como algo importante para as futuras gerações; 2) das percepções quanto ao PHA, onde se destaca a disputa sobre quem são os “atingidos”; 3) e do embate entre o que é planejado localmente e o que é imposto sob égide do “desenvolvimento”. O estudo de tais competências permitiu caracterizar a tendência das ordens de justificação evocadas pelos agentes contrários ao PHA em críticas: a) ambiental e estética; b) ambiental e social; c) críticas às práticas da empresa ao modelo desenvolvimento. Por outro lado, apresentam-se as justificativas acionadas pelo ente criticado e pelo pólo favorável ao PHA: a) projeto país; b) desenvolvimento e progresso regional e nacional; e c) críticas ao ambientalismo. Por fim, averiguou-se a existência de todos os elementos necessários para a construção bem sucedida de um problema ambiental conforme os fatores elencados por Hannigan (2009). Contudo, considerou-se precipitado afirmar que a presença destes elementos são as condicionantes que tornam este conflito excepcional, ficando o indicativo da importância da realização de futuros estudos em perspectiva comparada de conflitos ambientais para maiores inferências. / This research analyses the process of formation of the conflict over environmental issues surrounding the establishment of the HidroAysén Hydropower Plant (PHA), approved for the Aysén Region, located at Chilean Patagonia. A joint venture formed in 2006 between the binational (Spanish and Italian investiment) ENDESA (51%) and the Chilean Colbún (49%), aims to build a complex of five hydroelectric power plants located in the Baker and Pascua Rivers. Since its oficial announcement, the Project has arisen intense controversy in what regards both its demages to the environment, and the probity on the issuing of enviroment certifications. An active movement of resistance has convened around the so called “Patagonia Sin Represas” (“Patagonia without dams”), providing momentum to the public debate against the PHA and obtaining favorable judicial pronouncements to obliterate the construction of the dam. This has resulted in an increase on the morale of the cause against the PHA. Against this scenario, this research aimed at comprehending in what ways do a local demand transcends the local dimension and turn into a broader demand, echoing in the breader national sphere. For that purpose, this research draws on Luc Boltanski (2010) theoretical and epistemological contribution, as well as on the constructionist synthesis as ellaborated by John Hannigan to investigate the collective and individual mobilization and actions taken against the PHA. A priority was given to the decomposition of the tread of actions taken, identifying the actors engaged (enviromenmentalists, land owners, NGO’s, etc.), in order to clarify the negotiation contained in the phenomena and the objects in which the parties rely on in the search to validate their positions. The research field has been effectuated in 2013, between may and august, in Santiago and in other four different locations adjacent to the projects Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins. There has been employed a combination of a certain number of qualitative methods for data collection: direct observation, Flick’s (2008) episodic narratives interview, photography, research on documents and notes taken in field diaries. As a result, there has been possible to observe that certain competences emerge within three given situations: 1) the necessity to instate Patagonia as common good through means of qualification of the environmental rhetoric, placing it as importante for future generations; 2) perceptions of the PHA, in especial regards to those deemed directly “affected by the dam”, and 3) the disputes between that which is planned locally and that, otherwise, is imposed under the áuspices of the “development”. The study of those competencies allowed for characterizing the tendencies in the order of justification by the critics of the PHA: a) environmental and esthetical; b) environmental and social; and c) critical to the practices assumed by the joint venture, responsible for the PHA, in terms of the present paradigm of development. On the other hand, the research also presents the arguments for the justification posed by the part being criticized, the PHA supporters and its advocates: a) project of Nation; b) development and regional and national progress; c) criticism to the environmentalist. All the elements enumerated by Hannigan (2009), and deemed as necessary for the establishment of a well succeeded environmental agenda, were detected in this research. Nevertheless, it’s been considered still early to draw affirmative conclusions as to whether the presence of these elements are a condition for the exceptionality of the conflict. Notwithstanding, this remains as an indication of the importance for the realization of future comparative studies in the same realm of research.
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A batalha pela Patagônia Chilena : o processo de formulação e operação das críticas ao projeto hidrelétrico "HidroAysén" e a construção de um conflito ambientalAranda, Yara Paulina Cerpa January 2014 (has links)
Esta pesquisa analisa o processo de constituição do conflito ambiental em torno ao Projeto Hidrelétrico HidroAysén (PHA), proposto para Região de Aysén, Patagônia chilena. O consórcio conformado em 2006 pela empresa hispano-italiana, ENDESA (51%) e a chilena Colbún (49%), propõe a construção de um complexo hidrelétrico de cinco represas nos rios Baker e Pascua. Desde seu anúncio, o projeto foi alvo de controvérsia quanto aos possíveis impactos e denúncias de falências no estudo de impacto ambiental. Sob a reivindicação de uma “Patagônia Sem Represas”, um amplo movimento opositor ao PHA organizou-se impulsionando o debate, impedindo o andamento do empreendimento por via judicial e obtendo um relativo sucesso em termos de repercussão e adesão à “causa”. Neste cenário, o objetivo geral do estudo é compreender de que forma uma demanda transcende o local para se tornar uma demanda nacional. Deste modo, a partir da perspectiva teórica-epistemológica de Luc Boltanski (2010) e colaboradores articulada à síntese construcionista de John Hannigan (2009) investigam-se as ações e mobilizações coletivas e individuais contrárias ao PHA. Para tanto, priorizou-se decompor o fio das ações, identificando os agentes engajados (conservacionistas, produtores rurais, ONG’s, entre outros), apresentando a experiência negociada na convergência de um interesse em comum e evidenciando os objetos em que estes se apóiam para formular e referendar a validade de suas argumentações. A pesquisa de campo foi realizada entre maio e agosto de 2013, em Santiago do Chile e em quatro localidades adjacentes ao projeto em Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins, utilizando-se uma combinação de procedimentos qualitativos, como: observação, entrevistas narrativas episódicas de Flick (2008), fotografia, pesquisa documental e diário de campo. Como resultado, observou-se que as competências emergem de três situações: 1) da necessidade de instaurar a Patagônia como um bem comum por meio de uma qualificação ambiental das justificativas, colocando-a sistematicamente como algo importante para as futuras gerações; 2) das percepções quanto ao PHA, onde se destaca a disputa sobre quem são os “atingidos”; 3) e do embate entre o que é planejado localmente e o que é imposto sob égide do “desenvolvimento”. O estudo de tais competências permitiu caracterizar a tendência das ordens de justificação evocadas pelos agentes contrários ao PHA em críticas: a) ambiental e estética; b) ambiental e social; c) críticas às práticas da empresa ao modelo desenvolvimento. Por outro lado, apresentam-se as justificativas acionadas pelo ente criticado e pelo pólo favorável ao PHA: a) projeto país; b) desenvolvimento e progresso regional e nacional; e c) críticas ao ambientalismo. Por fim, averiguou-se a existência de todos os elementos necessários para a construção bem sucedida de um problema ambiental conforme os fatores elencados por Hannigan (2009). Contudo, considerou-se precipitado afirmar que a presença destes elementos são as condicionantes que tornam este conflito excepcional, ficando o indicativo da importância da realização de futuros estudos em perspectiva comparada de conflitos ambientais para maiores inferências. / This research analyses the process of formation of the conflict over environmental issues surrounding the establishment of the HidroAysén Hydropower Plant (PHA), approved for the Aysén Region, located at Chilean Patagonia. A joint venture formed in 2006 between the binational (Spanish and Italian investiment) ENDESA (51%) and the Chilean Colbún (49%), aims to build a complex of five hydroelectric power plants located in the Baker and Pascua Rivers. Since its oficial announcement, the Project has arisen intense controversy in what regards both its demages to the environment, and the probity on the issuing of enviroment certifications. An active movement of resistance has convened around the so called “Patagonia Sin Represas” (“Patagonia without dams”), providing momentum to the public debate against the PHA and obtaining favorable judicial pronouncements to obliterate the construction of the dam. This has resulted in an increase on the morale of the cause against the PHA. Against this scenario, this research aimed at comprehending in what ways do a local demand transcends the local dimension and turn into a broader demand, echoing in the breader national sphere. For that purpose, this research draws on Luc Boltanski (2010) theoretical and epistemological contribution, as well as on the constructionist synthesis as ellaborated by John Hannigan to investigate the collective and individual mobilization and actions taken against the PHA. A priority was given to the decomposition of the tread of actions taken, identifying the actors engaged (enviromenmentalists, land owners, NGO’s, etc.), in order to clarify the negotiation contained in the phenomena and the objects in which the parties rely on in the search to validate their positions. The research field has been effectuated in 2013, between may and august, in Santiago and in other four different locations adjacent to the projects Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins. There has been employed a combination of a certain number of qualitative methods for data collection: direct observation, Flick’s (2008) episodic narratives interview, photography, research on documents and notes taken in field diaries. As a result, there has been possible to observe that certain competences emerge within three given situations: 1) the necessity to instate Patagonia as common good through means of qualification of the environmental rhetoric, placing it as importante for future generations; 2) perceptions of the PHA, in especial regards to those deemed directly “affected by the dam”, and 3) the disputes between that which is planned locally and that, otherwise, is imposed under the áuspices of the “development”. The study of those competencies allowed for characterizing the tendencies in the order of justification by the critics of the PHA: a) environmental and esthetical; b) environmental and social; and c) critical to the practices assumed by the joint venture, responsible for the PHA, in terms of the present paradigm of development. On the other hand, the research also presents the arguments for the justification posed by the part being criticized, the PHA supporters and its advocates: a) project of Nation; b) development and regional and national progress; c) criticism to the environmentalist. All the elements enumerated by Hannigan (2009), and deemed as necessary for the establishment of a well succeeded environmental agenda, were detected in this research. Nevertheless, it’s been considered still early to draw affirmative conclusions as to whether the presence of these elements are a condition for the exceptionality of the conflict. Notwithstanding, this remains as an indication of the importance for the realization of future comparative studies in the same realm of research.
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Hydrogeomorphic classification of mire ecosystems within the Baker and Pascua Basins in the Region Aysén, Chilean PatagoniaMartínez, Ana Carolina Rodríguez 15 September 2015 (has links)
Zehn unerforschte und natürliche Moore entlang der Flüsse Baker und Pascua in der Region Aysén, im chilenischen Patagonien, wurde untersucht, um Informationen über ihre Entstehung, Hydrologie, Geomorphologie, Stratigraphie, Ökologie und Wasser- und Kohlenstoffspeichervermögen zu gewinnen. Es wurden acht verschiedene ökologische Moortypen identifiziert und fünf Moortypen unterscheidbar durch ihr geohydromorphologisches Setting mit insgesamt elf verschiedenen organischen Moorsubstraten. Die gesammelten Information erlauben erste Abschätzungen der Torf-, Süßwasser- und Kohlenstoffmengen, die in den Mooren Ayséns gespeichert sind, sowie der jährlichen Torfakkumulationsraten. Die Moortypen und die in ihnen vorkommenden organischen Substrate wurden in einem geohydromorphologischen Klassifizierungssystem zusammengefasst, welches wichtige hydrologische, geomorphologische, ökologische, bodenkundliche und landschaftliche Parameter integriert. Forschung und Kommunikation über die chilenischen Moore sollen durch diese Arbeit unterstützt werden, um angemessene Monitoring Tools und partizipative Naturschutzstrategien zu entwickeln, die für die Erhaltung dieser Ökosysteme und ihrer Kreisläufe anwendbar sind. / Ten unexplored and pristine mires along the Baker and Pascua River Basins in Aysén, Chilean Patagonia, were examined, generating information about their origin, hydrology, geomorphology, stratigraphy, ecology, and carbon and water storage capacities. Eight mire types ecologically differentiable, associated with five main mire types separable by their hydrology and geomorphology were detected, as well as eleven organic substrate types forming mire soils. The information gathered allows for a first estimation of the peat, fresh water and carbon content stored in the mires of Aysén, as well as for an average growth and annual accumulation rate of the peat. Mire types and their associated substrates are systematized in a hydrogeomorphic classification system, integrating important landscape, hydrological, geomorphical, ecological and pedological components. Research and communication about mires in the Chilean Patagonia should be further supported to generate accurate monitoring tools and participative conservation strategies that are replicable for the preservation of these ecosystems and its balance.
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