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Benavides, Benavides Rafael Ángel, Zúñiga José Walter García i Jara Juan Carlos Moreno. "Valorización de Austral Group S.A.A". Master's thesis, Universidad del Pacífico, 2018. http://hdl.handle.net/11354/2151.
Pełny tekst źródłaSallée, Jean-Baptiste. "Les eaux modales de l'Océan Austral". Phd thesis, Université Paul Sabatier - Toulouse III, 2007. http://tel.archives-ouvertes.fr/tel-00193791.
Pełny tekst źródłaLa formation des SAMW est intimement liée à la dynamique océanique Australe et à la position des principaux fronts polaires. Une deuxième étude concerne la circulation de l'ACC et la variabilité frontale. Dans cette étude, nous avons tiré parti de la complémentarité des données in situ et altimétriques afin de suivre l'évolution des deux principaux fronts de l'ACC pendant la période 1993-2005. Nous avons comparé leurs mouvements avec les deux principaux modes de variabilité atmosphérique de l'Hémisphère Sud, le mode annulaire Austral (SAM) et l'Oscillation Australe El-Niño (ENSO). La position moyenne des fronts est déterminée avant tout par les fonds océaniques. Cependant, nous avons trouvé que dans les régions à fond plat, les fronts forment de grands méandres dus à l'activité tourbillonnaire et aux forçages atmosphériques.
En parallèle, nous avons développé une nouvelle estimation de la distribution circumpolaire de la diffusion dans l'Océan Austral. La diffusion n'a presque jamais été étudiée à partir de données in situ dans cet océan. Nous avons calculé une estimation du coefficient de diffusion tourbillonnaire à partir d'une analyse statistique de dix années de trajectoires de dériveurs de surface. Nous avons cartographié ce coefficient dans l'Océan Austral, puis nous l'avons paramétré à partir de données altimétriques pour pouvoir en étudier l'évolution inter-annuelle et en faciliter l'utilisation dans le futur. Cette étude montre que l'Océan Austral est fortement diffusif au nord de l'ACC, et particulièrement près des courants de bord Ouest, c'est à dire dans la Rétroflexion des Aiguilles, dans la région du plateau de Campbell, et dans le courant de Brésil-Malouines.
Ces résultats nous ont menés à une analyse circumpolaire de la formation des SAMW, et à une meilleure conception du lien entre la dynamique océanique Australe et la formation des SAMW. La croissance constante des données hydrologiques du programme ARGO dans l'Océan Austral nous a également permis de mieux représenter la répartition des régions de formation des SAMW. Nous avons trouvé que la diffusion tourbillonnaire joue un rôle majeur dans les budgets de chaleur locaux. Au Sud des courants de bord Ouest, et au nord du SAF, la diffusion tourbillonnaire apporte de la chaleur, équilibrant et même dominant les refroidissements hivernaux dus aux flux d'Ekman et aux flux air-mer. Elle réduit en particulier la déstabilisation de la couche de mélange au nord du SAF dans l'Ouest du bassin Indien, en aval de la Rétroflexion des Aiguilles, et dans l'Ouest du bassin Pacifique, en aval du Plateau de Campbell.
Sánchez, Grellet Beatriz Marcela. "Exportación de Merluza Austral a Suecia". Tesis, Universidad de Chile, 2009. http://www.repositorio.uchile.cl/handle/2250/102210.
Pełny tekst źródłaTotten, Christopher Lee. "To be FRANK : Austral-Asian Performance Ensemble /". [St. Lucia, Qld.], 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17845.pdf.
Pełny tekst źródłaSalinas, García Hugo Ernesto, i Sánchez Percy Paul Ortega. "Valorización de la empresa Austral Group S.A.A". Trabajo aplicativo final, Universidad Peruana de Ciencias Aplicadas - UPC. Escuela de Postgrado, 2014. http://hdl.handle.net/10757/311351.
Pełny tekst źródłaRuiz, Alquinta Manuel. "Acerca del problema la conectividad en la Zona Austral de Chile: el caso de la Carretera Austral 1976-1996". Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/145212.
Pełny tekst źródłaMadon-Senez, Céline. "Disparité morphologique et architecturale des schizasteridae incubants (Echinoidea, Spatangoïda) des régions australes". Dijon, 1998. http://www.theses.fr/1998DIJOS065.
Pełny tekst źródłaFuzs, Gonzalo. "Austral 1938-1944: lo individual y lo colectivo". Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/109039.
Pełny tekst źródłaMaze, Guillaume. "Interactions Basses Frequences Ocean-Atmosphere dans l'Ocean Austral". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2006. http://tel.archives-ouvertes.fr/tel-00515553.
Pełny tekst źródłaJones, Donoso Daniela Constanza. "Red de Alojamiento Turístico en la Carretera Austral". Tesis, Universidad de Chile, 2009. http://www.repositorio.uchile.cl/handle/2250/102147.
Pełny tekst źródłaTalbot, Vincent. "Activité protéolytique et dynamique bactérienne en Océan Austral". Aix-Marseille 2, 1995. http://www.theses.fr/1995AIX22113.
Pełny tekst źródłaMaze, Guillaume. "Interactions basses fréquences océan-atmosphère dans l'océan Austral". Paris 6, 2006. https://tel.archives-ouvertes.fr/tel-00515553.
Pełny tekst źródłaXavier, Nathaly Silva. "Integração na África Austral : a comunidade para o desenvolvimento da África Austral (SADC) e os condicionantes históricos e políticos da integração". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/106413.
Pełny tekst źródłaThe Community for the Southern African Development Community (SADC) is one of the main regional integration processes in Africa. The creation of the Community has its origins in the process of decolonization in Southern Africa and in the Front Line States the mobilization to contain the destabilization policies by South Africa during the apartheid period. The concept of developmental regionalism, in which the processes of regional integration have broader objectives than purely commercial, folows the reality of Southern Africa. The concept of security community is also useful for understanding regional relations involving the creation and development of SADC over the decades, concerning your activity also in security issues. The aim of this study is to analyze the evolution of SADC since its creation until the 2000’s, emphasizing the historical and political aspects of this process. It adopts the assumption that there is a strong relationship between security, development, integration and peace and there is no way to deepen economic integration in a context of regional political and security instability.
La Communauté de Développement de l'Afrique Australe est l'un des principaux processus d'intégration régionale en Afrique . La création de la Communauté est fondée dans le processus de décolonisation en Afrique australe et dans la mobilisation de les État du Linge de Front pour contenir les politiques de déstabilisation de l'Afrique du Sud au cours de la période de l'apartheid. Le concept de régionalisme développementiste, dans lequel les processus d'intégration régionale ont des objectifs plus larges que purement commerciale, répond à la réalité de l'Afrique Australe . Le concept de communauté de sécurité est également utile pour comprendre les relations régionales sur la création et le développement de la SADC au cours des décennies , en vue de ses performances aussi dans les questions sécuritaire . L’objectif de cette étude est d'analyser l'évolution de la SADC depuis sa création jusqu'aux années 2000 , mettant l'accent sur les aspects historiques et politiques de ce processus . Séjours à l'hypothèse selon laquelle il existe une relation forte entre la sécurité, le développement, l'intégration et la paix et il n'ya aucun moyen d'approfondir l'intégration économique dans un contexte d’instabilité politique et securitaire régionale.
Ferron, Bruno. "Ecoulement de l'eau antarctique de fond dans la zone de fracture romanche". Brest, 1998. http://www.theses.fr/1998BRES2042.
Pełny tekst źródłaCraneguy, Philippe. "Mécanismes d'intrusion de l'eau antarctique intermédiaire antarctique à travers le courant circumpolaire antarctique". Brest, 1999. http://www.theses.fr/1999BRES2016.
Pełny tekst źródłaBouhier, Nicolas. "Etude de l'impact des icebergs Antarctiques sur l'Océan Austral". Thesis, Brest, 2017. http://www.theses.fr/2017BRES0143/document.
Pełny tekst źródłaThe Antarctic polar ice cap constrains a freshwater flaux into the Austral Ocean through two equally important pathways : a localized and immediate injection through the melting of ice-shelves bases, and a delayed offshore injection through the calving and subsequent melt of icebergs. Some studies reckon that melting icebergs have the capacity to alter the hydrological and biogeo-chemical characteristics of the water column. The numerical models trying to evaluate this impact have shown contrasting results. Yet, they might suffer from a poor representation of the icebergs, namely due to our limited knowledge on both the spatial and size distributions of the icebergs, or even the processes involved in their mass loss. A new method using satellite altimetry measurements has lead to the creation of a database mapping Antarctic icebergs distribution with an unprecedented spatial and temporal coverage. Our joint analysis between these data and sea ice concentration fields highlights a possible transport of the freshwater injected by an iceberg and its impacts on sea ice.We also analyze the links between icebergs of different sizes : the large ones can be seen as ice buffers that diffuse across the whole ocean when breaking into small fragments of various sizes. We finally study the evolution of two giant icebergs, suggest the first parametrization of the fragmentation process and analyze the subsequent size distribution of the fragments. These results can be valuable to account in a more realistic way the fresh water flux constrained by icebergs in models
Viljoen, Jan-Adriaan. "Ecological influences in the biogeography of the Austral sedges". Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20302.
Pełny tekst źródłaGuevara, Navea Cristian Felipe. "Formación de Estrellas Masivas en la Galaxia Externa Austral". Tesis, Universidad de Chile, 2011. http://repositorio.uchile.cl/handle/2250/102543.
Pełny tekst źródłaVerdier, Olivier. "Champs géothermiques et zéolitisation des îles Kerguelen : implications géologiques (Terres australes et antarctiques françaises, océan indien austral)". Paris 6, 1989. http://www.theses.fr/1989PA066503.
Pełny tekst źródłaVerdier, Olivier. "Champs géothermiques et zéolitisation des Iles Kerguelen implications géologiques, terres australes et antarctiques françaises, Océan indien austral". Grenoble : ANRT, 1989. http://catalogue.bnf.fr/ark:/12148/cb37593886j.
Pełny tekst źródłaBucciarelli, Eva. "Rôle du fer dans le contrôle de la pompe biologique de CO2 de l'océan austral". Brest, 2001. http://www.theses.fr/2001BRES2041.
Pełny tekst źródłaThis work concerns the role played by iron in controlling the CO2 biological pump in the Southern Ocean. Iron, indeed, is a micro-nutrient essential to life and numerous experiments have shown that its subnanomolar concentrations in the water column (co)-limited the primary production in various oceanic areas, e. G. In the Southern Ocean. The thesis is divided in two complementary parts, a geochemical part and a biogeochemical one. The geochemical part aims at a better understanding of the oceanic geochemical cycle of iron. It presents measurements of dissolved iron and manganese in the wake of the Kerguelen Islands (Bucciarelli et al. 2001) and of dissolved and total dissolvable iron in the open Southern Ocean (Crozet basin). The samplings were conducted as part of the Antares program (France JGOFS), during the Antares 3 cruise in the wake of the Kerguelen island, and during the Antares 4 cruise in the Crozet Basin. The data give insigths into the sources and sinks of iron in the Indian sector of the Southern Ocean. The biogeochemical part focuses on the effects of iron stress on natural phytoplanktonic community on one hand (Blain et al. 2001, Blain et al. 2002, Sedwick et al. 2002), and on laboratory monospecific cultures of three species of diatoms on the other hand. A decoupling between the cycles of silicon, carbon and nitrogen has been shown under iron stress conditions. The decoupling is quantified in a range of iron concentrations varying from iron-limiting to iron-sufficient conditions
Pasquer, Bénédicte. "Modélisation de la pompe biologique de carbone dans l'Océan Austral". Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210937.
Pełny tekst źródłaPierrat, Benjamin. "Macroécologie des échinides de l'océan Austral : Distribution, Biogéographie et Modélisation". Phd thesis, Université de Bourgogne, 2011. http://tel.archives-ouvertes.fr/tel-00717643.
Pełny tekst źródłaSáez, San Juan Roberto Andrés. "Centro Austral de investigación en humedales. Difusión, conservación, investigación, docencia". Tesis, Universidad de Chile, 2015. http://repositorio.uchile.cl/handle/2250/135309.
Pełny tekst źródłaLa Selva Valdiviana, ecosistema de invaluable aporte ecológico a nivel mundial, se encuentra en la mira de distintas organizaciones internacionales para el resguardo del equilibrio ecológico por su particular y amplia biodiversidad, considerando las amenazas antrópicas y la fragilidad del lugar, convirtiéndose en un paisaje único en el país, tanto por su belleza, como por la abundancia de especies que contiene. En dicha ecorregión se encuentra situado el Humedal del rio Cruces, provocado tras el terremoto de 1960, por el hundimiento e inundación del territorio. Ubicado al norte de Valdivia, Santuario de la Naturaleza y primer sitio en Chile declarado Ramsar, cubre una superficie aproximada de 4.877 há. Con unos 25 Km. de largo y un ancho promedio de 2 Km. En 2004 sufre las consecuencias de un desastre ambiental, cuando es roto el equilibrio del humedal tras la descarga de riles de la industria celulosa Arauco, siendo contaminadas sus aguas, dando muerte al luchecillo, base alimenticia del lugar, provocando la masiva muerte o migración de aves como el Cisne de Cuello Negro. La situación se torna un problema a nivel nacional, situándose como un hito en la historia del cuidado medioambiental del país. El Estado de Chile demanda a la Celulosa Arauco, declarada responsable del desastre, siendo sentenciada a compensar el daño por medio de la creación del Centro de Investigación del Humedales. La universidad Austral, asume la gestión como compromiso con dicho centro, además de destinar un terreno dentro del campus Teja. Chile, país rico en recursos naturales no puede permitir la destrucción progresiva de ecosistemas como el HRC, que en estado de equilibrio nutren no solo la economía del país, sino que proveen resguardo frente a desastres naturales y garantizan una mejor calidad de vida a los asentamientos humanos cercanos. Por lo tanto, es importante el estudio y manejo responsable de los ecosistemas húmedos, por su alto valor ecológico y para dar herramientas a la industria extractiva en materia de resguardo del equilibrio a lo largo del tiempo. Se debe diseñar un proyecto que albergue la actividad científica, la investigación y la docencia en torno a los humedales, pero que en definitiva, sea un aporte a una cultura alrededor de estos ecosistemas, promoviendo desde distintas perspectiva su conservación y manejo sostenible, reconociendo su importancia en el equilibrio ambiental de gran parte del territorio nacional donde se encuentran. El edificio deberá contar con el resguardo necesario ante el clima y las intensas lluvias propias de la zona, y una ubicación estratégica que genere un dialogo entre Valdivia y el Humedal, consolidando así un circuito ecológico educativo dentro del campus Teja de la UACH.
Vargas, Ugarte S. J. Ruben. "Coloquio XXXIII de la "Miscelánea Austral'', de Avalos y Figueroa". Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/113759.
Pełny tekst źródłaVargas, Ugarte S. J. Ruben. "Don Diego de Avalós y Figueroa y la "Miscelánea Austral''". Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/114482.
Pełny tekst źródłaTchova, Daniel Chico. "A política externa de Angola na África Austral (1975-1992)". Master's thesis, Universidade de Évora, 2015. http://hdl.handle.net/10174/13259.
Pełny tekst źródłaChaigneau, Alexis. "Variabilité de la couche superficielle de l'océan austral entre la Tasmanie et l'Antarctique". Toulouse 3, 2003. http://www.theses.fr/2003TOU30108.
Pełny tekst źródłaErrhif, Ahmed. "Composition et structure du zooplancton du secteur indien de l'océan austral : rôle du métabolisme respiratoire". Aix-Marseille 3, 1998. http://www.theses.fr/1998AIX30052.
Pełny tekst źródłaBrévière, Emilie. "Variabilités temporelles des flux de CO2 à l'interface air-mer dans l'océan Indien et Austral au sud de la Tasmanie". Paris 6, 2005. https://tel.archives-ouvertes.fr/tel-00080464.
Pełny tekst źródłaMainsant, Gildas. "Réponse des masses d'eau intermédiaires et modales de l'océan Austral au mode annulaire austral : les processus en jeu et rôle de la glace de mer". Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU060/document.
Pełny tekst źródłaRecent climate trends show a warming and freshening of the surface layers in the region of the Antarctic Circumpolar Current (ACC). Over the same period, the westerlies driving the circulation of the Southern Ocean have significantly increased. This increase is partly due to the intensification of the Southern Annular Mode (SAM), the main mode of atmospheric variability south of 20°S. In this thesis, we are interested in understanding the effects of the positive trend of the SAM onto the properties of water masses formed in the region of the ACC. To do so, we implement a strategy of regional coupled ocean-sea ice simulations forced by a series of atmospheric disturbance scenarios.These scenarios are constructed from atmospheric reanalyses in order to describe the various components (dynamic and thermodynamic) of the changes related to the SAM. In response to the increase of the SAM, the simulations show a significant salinification of the ocean mixed layer and of the mode water (SAMW) and intermediate water (AAIW).Most of these changes can be attributed to the dynamic components of the SAM. In Seasonal Ice Zone, the thermodynamic components of the SAM can play an important part (especially in Amundsen Sea and Weddell Sea). The simulations also show the key role played by sea ice in mediating atmospheric changes toward the interior ocean.These simulation results suggest that SAM is not the only driver of recent climate trends in the Southern Ocean
Bottini, Silvana de Sanfilli. "Distribuição espacial e padrões de movimento da baleia-franca-austral (Eubalaena australis) em Torres, Rio Grande do Sul, Brasil". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/131934.
Pełny tekst źródłaBenallal, Mohamed. "Analyse d'images satellitaires et développement d'outils informatiques pour modéliser le transfert de CO₂ à l'interface air-mer dans les régions subantarctique et antarctique (secteur Australien)". Thesis, Perpignan, 2016. http://www.theses.fr/2016PERP0024/document.
Pełny tekst źródłaA step by step algorithm for air-sea CO2 flux (FCO2) calculation from satellite (sat) parameters is developed and presented presented in this thesis. Parameters used for this calculation are: sea surface temperature (SST) and chlorophylla (Chla) from MODISAqua satellite, sea surface salinity (SSS) estimated from MODISAqua SST using MLR, seawater CO2 fugacity (fCO2sw) estimated by MODISAqua SST and chla using FNN, atmospheric CO2 fugacity from the Cape Grim station and wind speed from QSCAT and ASCAT satellites. In situ data provided by several projects collected on the RV L'Astrolabe, are used to establish and validate the models. These models are then tested using sat data. This work focus on the Australian sector of the southern ocean. Results show: an improvement of satellite SSS estimation with a precision of ±0.16 using SST and latitude, an estimation of fCO2sw with a good accuracy of ±9.45 µatm and a calculation of FCO2 with a global RMSE of about ±3 mmol CO2 m−2 d−1. Programs and models developed in this study allow us to interpolate FCO2. In the period of austral spring and summer, this region is becoming a stronger sink of atmospheric CO2 throughout the years
Van, Der Molen Silvina. "Estudio sobre la reproducción de Notothenioidei (Pisces: Perciformes) del Océano Austral". Doctoral thesis, Universitat Autònoma de Barcelona, 2003. http://hdl.handle.net/10803/3659.
Pełny tekst źródłaLas aguas de plataforma y talud están dominadas, en términos de biomasa y diversidad, por un solo suborden endémico: Notothenioidei. Como en la mayoría de los vertebrados, la reproducción de los peces es un fenómeno cíclico. En los teleósteos en general, esta periodicidad es anual y se rige por las variaciones estacionales de las condiciones ambientales. Se ha sugerido, como norma general, un acoplamiento espacio-temporal de los ciclos reproductivos con los ciclos de producción primaria. Sin embargo, algunas de las especies antárticas parecen desviarse de este criterio. El desacoplamiento de los ciclos reproductivos con las fluctuaciones temporales de la producción primaria podría representar una ventaja evolutiva para algunas especies, dado que su éxito reproductivo constituiría un suceso independiente de las variaciones anuales.
Para una comprensión de la biología de los peces que viven en las peculiares condiciones que impone el Océano Austral, es de gran interés el estudio de sus adaptaciones. En los Notothenioidei, la reproducción parece ser un parámetro clave de estas adaptaciones. Dado que han experimentado una gran radiación adaptativa, es de suma importancia apreciar si las estrategias reproductivas que presentan sufrieron también cambios a lo largo de su historia evolutiva. Es decir, examinar si los parámetros que describen la biología reproductiva de las especies, presentan alguna particularidad relacionada con el resto de las adaptaciones que presenta este grupo.
El objetivo general de este trabajo es reconstruir el ciclo biológico de varias especies del suborden Notothenioidei, a partir del estudio histoquímico de la ovogénesis, interpretando luego su papel ecológico y evolutivo.
Los parámetros reproductivos vinculados a la duración del período reproductivo, fecundidad, madurez sexual, desove y estacionalidad fueron analizados en ejemplares pertenecientes a las familias Channichthyidae, Harpagiferidae, Artedidraconidae y Bathydraconidae (Pisces: Perciformes).
Los resultados obtenidos reflejan que las diferencias en las estrategias reproductivas que presenta este grupo se basan principalmente en el aprovechamiento diferencial de los recursos, ya sean espaciales y temporales o tróficos. Es decir que, a pesar de la alta diversidad fenotípica que muestra este grupo en lo referente a estrategias reproductivas, los Notothenioidei no han desarrollado adaptaciones específicas en este sentido, que los distingan de otros grupos de teleósteos.
The Antarctic continent shows the most extreme environmental conditions. The stable temperatures of the Southern Ocean are at or near the freezing point of sea water. Although antarctic waters exhibit low seasonal variability in temperature, light, development of sea-ice and primary production show marked seasonal fluctuations. Thus the antarctic fauna is subject to extreme environmental conditions and exhibit particular adaptations. The major features of the biology of antarctic marine poikiloterms are low metabolism, seasonal growth rates, large yolky eggs and delayed maturity. Many authors also suggested that reproductive cycles appear to be closely linked to the primary production cycle
The antarctic fauna is smaller and much less diverse on a higher taxonomic level (order, family) than might be expected given the considerable age and large area of the ecosystem. The shelf and slope waters are dominated both in therms of species and biomass by a single, endemic perciform suborder, the Notothenioidei. Some of the common characteristics of this suborder are: slow growth, prolonged gametogenesis, low fecundity and large yolky eggs. As in most vertebrates, reproduction in fish is a cyclic phenomenon, generally in Teleost fishes this periodicity is annual and it is influenciated by environmental changes. However, some antarctic species show a different pattern and exhibit uncoupled reproductive cycles. It is possible that there could be selective advantages to be gained by species that are able to be independent of the production cycle and thereby avoid large variations in breeding success from year-to-year changes in the environment. To a better understanding of the biology of fish living in the extreme conditions of marine polar environment it is of great interest the study of the antarctic fauna adaptations. Reproduction is a key parameter in the study of notothenioidei adaptations. Describing oogenesis stages and sexual maturation, spawning characteristics and fecundity, the life cycle of these species can be reconstructed, giving basis knowledge about their biology.
The main objective of this project is to describe the characteristics of Notothenioiids reproductive cycle, its relation with environmental parameters and its intraspecific variation.
Based in oogenesis histochemical analysis, reproductive parameters such as fecundity, spawning and seasonality were evaluated in 9 species belonging to the families Channichtyidae, Artedidraconidae, Harpagiferidae and Bathydraconidae (Pisces: Perciformes).
Results reveal that the oocyte development events are very similar to those described for other notothenioids and for most other Teleost. Reproductive strategies in notothenioids differ mainly in the differential exploitation of temporal or spatial resources. Thus, these observations suggest that specialisation in Antarctic fish are more related to ecological diversification than to any kind of adaptation concerning oogenesis.
Jamine, Elísio Benedito [UNESP]. "A integração regional na África Austral: obstáculos e oportunidades (1980-2008)". Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/93745.
Pełny tekst źródłaConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Este trabalho aborda a atual tendência à constituição de novos blocos de integração regional a partir do ponto de vista da experiência da Southern African Development Community “Comunidade para o Desenvolvimento da África Austral” (SADC). Busca-se compreender o seu desenvolvimento histórico, sua dinâmica político-econômica sobre os desafios e oportunidades para o contínuo desenvolvimento e consolidação deste bloco regional em seu contexto regional e continental. Argumenta-se que o passado da cooperação entre os Estados da região e a emergência em 1980 da Southern African Development Coordination Conference “Conferência de Coordenação para o Desenvolvimento da África Austral” (SADCC) foi em larga medida em resposta as tendências de dominação político-econômica sul-africana alicerçadas a sua política interna e regional baseada no apartheid e nas alianças inseridas no contexto da Guerra Fria. Enquanto que em 1992 a SADC emerge como uma vertente economicista-comercial que política, em função dos desafios regionais e da nova ordem internacional estabelecida no pós Guerra Fria e cujas respostas se baseiam na integração regional. O trabalho pretende contribuir na compreensão do passado e presente da cooperação e integração na África Austral. A abordagem compreende o período que vai de 1980 à 2008
This study addresses the current trend of new regional international blocks creation from the point of view of the experience of the Southern African Development Community “Comunidade para o Desenvolvimento da África Austral” (SADC). We intend to understand its historical development, politic-economics dynamics on the challenges and opportunities for continuous developing and consolidation of this regional block, within regional and continental context. We argue that the past of cooperation between region States and the emergence of the Southern African Development Coordination Conference “Conferência de Coordenação para o Desenvolvimento da África Austral” (SADCC) was largely in response to trends of South Africa’ political and economic domination based on its domestic and regional policy of apartheid and on the alliances inserted in the Cold War. While the SADC emerges as an economiccommercial approach than politics, in light of regional challenges and that of the new international order, whose answers are based on regional integration. The study aims to contribute to the understanding of the past and present cooperation and integration in Southern Africa. The approach includes the period from 1980 to 2008
Saunders, Debra, i debbie saunders@anu edu au. "Ecology and conservation of the swift parrot - an endangered austral migrant". The Australian National University. College of Science, 2008. http://thesis.anu.edu.au./public/adt-ANU20081010.161656.
Pełny tekst źródłaPereira, Janini. ""Variabilidade do Oceano Austral usando um modelo acoplado de circulação geral"". Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/21/21132/tde-24102003-125856/.
Pełny tekst źródłaIn this study the climatic variability of the Southern ocean and the Antarctic Circumpolar Wave (ACW) are investigated. The National Center for Atmospheric Research/ Community System Model _ NCAR CCSM coupled model 150 years simulation data is compered with the climatology data from the Nacional Center for Envirommental Prediction - NCEP/NCAR Re-analysis, for a period from january/1948 until july/2002. Annual and seasonal climatology and harmonic analysis are used for the following variables: sea surface temperature (SST), sea level pressure (SLP), meridional and zonal wind. Hovmoeller diagrams, potencial spectra and statistics methods such as Empirical Ortogonal Functions (EOF) and Singular Value Decomposition (SVD) are used to analyze changes in interannual behavior of this variables.
Corbeau, Alexandre. "Relations entre oiseaux marins et pêcheries : Albatros sentinelles de l’océan Austral". Thesis, La Rochelle, 2020. http://www.theses.fr/2020LAROS021.
Pełny tekst źródłaThe current 6th major species extinction crisis is also affecting seabirds, especially albatrosses. Their populations have decreased by 70% over the last 60 years, mainly due to mortality in longline fisheries. Large albatrosses cover enormous distances during their foraging trips and their curiosity and opportunism favour regular encounters with boats. Thus, they constitute privileged models for studying the relationships between seabirds and fisheries. During the course of this thesis, thanks to the development of new prototype loggers deployed on Wandering and Amsterdam albatrosses in the Indian Ocean and new methods for estimating by-catch risks, we were able to observe that natural foraging behaviours differ from those associated with a boat. Similarly, the intrinsic characteristics of birds (species, population, sex, age and personality) lead to differences in exposure to by-catch risk, particularly through the use of different habitats. Finally, we have shown that the characteristics of boats also have a strong influence on the risk of by-catch, in particular through the type of boats encountered, their legality, the fishing practices used and the presence of discards. We conclude by presenting new methods to better estimate the risks of by-catch and the need for fundamental knowledge of species and populations in order to better protect marine environments that are increasingly endangered
Jamine, Elísio Benedito. "A integração regional na África Austral : obstáculos e oportunidades (1980-2008) /". São Paulo : [s.n.], 2010. http://hdl.handle.net/11449/93745.
Pełny tekst źródłaBanca: Reginaldo Nasser
Banca: Vania Leal Cintra
O Programa de Pós-Graduação em Relações Internacionais é instituido em parceria com Unesp/Unicamp/PUC-SP, em projeto subsidiado pela CAPES, intitulado "Programa San Tiago Dantas"
Resumo: Este trabalho aborda a atual tendência à constituição de novos blocos de integração regional a partir do ponto de vista da experiência da Southern African Development Community "Comunidade para o Desenvolvimento da África Austral" (SADC). Busca-se compreender o seu desenvolvimento histórico, sua dinâmica político-econômica sobre os desafios e oportunidades para o contínuo desenvolvimento e consolidação deste bloco regional em seu contexto regional e continental. Argumenta-se que o passado da cooperação entre os Estados da região e a emergência em 1980 da Southern African Development Coordination Conference "Conferência de Coordenação para o Desenvolvimento da África Austral" (SADCC) foi em larga medida em resposta as tendências de dominação político-econômica sul-africana alicerçadas a sua política interna e regional baseada no apartheid e nas alianças inseridas no contexto da Guerra Fria. Enquanto que em 1992 a SADC emerge como uma vertente economicista-comercial que política, em função dos desafios regionais e da nova ordem internacional estabelecida no pós Guerra Fria e cujas respostas se baseiam na integração regional. O trabalho pretende contribuir na compreensão do passado e presente da cooperação e integração na África Austral. A abordagem compreende o período que vai de 1980 à 2008
Abstract: This study addresses the current trend of new regional international blocks creation from the point of view of the experience of the Southern African Development Community "Comunidade para o Desenvolvimento da África Austral" (SADC). We intend to understand its historical development, politic-economics dynamics on the challenges and opportunities for continuous developing and consolidation of this regional block, within regional and continental context. We argue that the past of cooperation between region States and the emergence of the Southern African Development Coordination Conference "Conferência de Coordenação para o Desenvolvimento da África Austral" (SADCC) was largely in response to trends of South Africa' political and economic domination based on its domestic and regional policy of apartheid and on the alliances inserted in the Cold War. While the SADC emerges as an economiccommercial approach than politics, in light of regional challenges and that of the new international order, whose answers are based on regional integration. The study aims to contribute to the understanding of the past and present cooperation and integration in Southern Africa. The approach includes the period from 1980 to 2008
Mestre
Tabeaud, Martine. "L'Atlantique tropical austral : l'eau atmosphérique et le climat en milieu océanique". Paris 4, 1989. http://www.theses.fr/1989PA040015.
Pełny tekst źródłaBetween 1961 and 1980 the water cycle above the southern tropical Atlantic is studied. This cycle begins with the evaporation at the ocean-atmosphere interface (springs) and ends with the condensation in the clouds (wells). The atmosphere dynamic provides the coherence between springs and wells, through internal and external advections. During a normal period (1961-1970), the seasons follow a typical pattern; in particular the austral winter. The St-Helen anticyclone, transoceanic, evaporates to a maximum. The trade winds, sweeping over the surface of the ocean, cool it. The outflow of water takes place on the continental borders. During a dry period (1971-1980), the anticyclone shrinks (the evaporation lessens as the trade winds slow down), the surface of the water is warmer and this increases the convection at the open sea. The water cycle grows shorter and the system does not outflow any longer toward Brazil or west Africa
Saunders, Debra L. "Ecology and conservation of the swift parrot : an endangered austral migrant /". View thesis entry in Australian Digital program, 2008. http://thesis.anu.edu.au/public/adt-ANU20081010.161656/index.html.
Pełny tekst źródłaGasperin, Débora Stefani. "DNA antigo de amostras de ossos de baleia-franca-austral, Eubalaena australis (Desmoulins, 1822) (Mysticeti, Cetartiodactyla) no Atlântico Sul Ocidental". Universidade do Vale do Rio dos Sinos, 2014. http://www.repositorio.jesuita.org.br/handle/UNISINOS/4270.
Pełny tekst źródłaMade available in DSpace on 2015-07-06T23:37:20Z (GMT). No. of bitstreams: 1 10a.pdf: 1719495 bytes, checksum: 2ed1add8423e889edf7e44b9eb1498f1 (MD5) Previous issue date: 2014-07
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A baleia-franca-austral (Eubalaena australis) foi alvo de grande exploração comercial entre os séculos XVII a XX no Hemisfério Sul. Estimativas recentes sugerem que a população mundial da espécie é de 12.000 indivíduos, o que representaria 17 a 21% do seu tamanho original. Apesar de aparente recuperação, o declínio drástico no tamanho da população, resultante dos 400 anos de atividade da caça, pode ter gerado altos níveis de endogamia, baixa capacidade reprodutiva e perda de variabilidade genética da espécie, podendo ter seu potencial adaptativo comprometido, aumentando assim a probabilidade de extinção. Frente ao exposto é de extrema importância a avaliação comparativa da variabilidade genética entre as populações atuais de E. australis e amostras representativas do período de caça, em especial no Brasil. Sendo assim, os objetivos deste estudo foram: I. Otimizar e comparar métodos de extração e amplificação de DNA antigo (aDNA) de ossos de baleia-franca-austral, em diferentes estados de degradação; II. Caracterizar geneticamente segmentos da região D-Loop do DNA mitocondrial (mtDNA) a partir de ossos de espécimes de E. australis coletados na Península Valdés na Argentina e em Santa Catarina no Brasil; e III. Comparar as sequências nucleotídicas da região recuperada nas amostras de aDNA com as descritas para as populações atuais. Este estudo comparou cinco métodos diferentes para obter material genético de amostras degradadas. O método de extração que mostrou ser mais eficiente foi o que continha o reagente Dextran Blue. Com a amplificação de 20 fragmentos curtos, obtidos pelo Nested-PCR, com clonagem e posterior sequenciamento, foi possível recuperar pequenos fragmentos, que variaram de 7 a 59 pb, da região D-Loop do mtDNA de 11 amostras de ossos de E. australis das 88 tentativas realizadas. Ao analisar o material recuperado com dados atuais da espécie, o programa Network 4.6 revelou uma rede contendo 19 haplótipos, sendo quatro haplótipos restritos as populações antigas e até então não descritos na literatura. Os resultados são preliminares e seus significados devem ser avaliados com muita cautela. Contudo, deve-se ressaltar que os quatro novos haplótipos encontrados podem sustentar a hipótese de uma maior diversidade haplotípica em E. australis quando a mesma era caçada comercialmente.
The Southern Right Whale (Eubalaena australis) was object of great commercial exploitation between the XVII and XX centuries in the Southern Hemisphere. Recent surveys suggest that the world’s population is of 12,000 specimens, which would represent 17% to 21% of its original size. Despite the supposed recovery, the drastic populational decline, resultant from 400 years of hunting activities, could have generated high levels of endogamy, low reproduction capacity and loss of genetic variability of the species, compromising their potential of adjustment, thus increasing their probability of extinction. Due to the exposed, it is of extreme importance the comparative evaluation of the genetic variability between the current E. australis population and representative samples from the hunting period, especially from Brazilian coast. Therefore, the purpose of this study was: I. To optimize and compare extraction and amplification methods of aDNA from Southern Right Whale’s bones in different stages of deterioration; II. To genetically characterize segments of the mtDNA’s D-Loop region from E. australis bones collected at Península Valdés in Argentina and Santa Catarina in Brazil, and III. To compare nucleotide sequences of the recovered region from aDNA samples with those described for the current populations. This study compared five different extraction methods in order to obtain genetic material from deteriorated samples. The extraction method containing Dextran Blue reagent showed the higher efficiency. With the amplification of 20 short fragments and overlapping of aDNA through Nested-PCR technique, and further cloning of the latter fragment, it was possible to sequence small fragments, varying from 7 to 59 pb, from the mtDNA’s D-loop region from 11 bones samples of E. australis, out of the 88 attempts performed. Analyzing the recovered material together with the updated data of the species, the Network 4.6 program revealed a network containing 19 haplotypes, 4 of them generated only with ancient population samples, which are new for the species. The results are still preliminary and their meanings should be evaluated with caution. However, it should be noted that the four new haplotypes found could support the hypothesis of a higher haplotype diversity in E. australis when it was hunted.
Mesquita, Críscia Cesconetto de. "Comportamento de pares fêmea-filhote de baleias-franca-austral, Eubalaena australis (Desmoulins, 1822) no litoral centro-sul de Santa Catarina". Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=6546.
Pełny tekst źródłaO litoral centro-sul do estado de Santa Catarina representa a mais importante área de concentração reprodutiva das baleias-franca-austral, Eubalaena australis, no Brasil. O objetivo deste estudo é caracterizar o padrão comportamental dos pares fêmea-filhote que migram para essas áreas ao longo de 10 temporadas reprodutivas (2003 a 2012). Observações realizadas em pontos fixos foram conduzidas de Julho a Novembro, entre 2003 e 2012, de seis a sete vezes por semana, entre as 6:00h e 17:00h. Os dados foram coletados com auxilio de binóculos Pentax 12x55 mm, bússola, relógio digital, e registrados em fichas de campo padronizadas. Os estados comportamentais (natação, descanso e ativo) foram registrados em intervalos de cinco minutos e a frequência de eventos registrada em cada intervalo de cinco minutos. Natação foi o estado comportamental que prevaleceu tanto para fêmeas e filhotes, seguido de descanso e ativo para as fêmeas e seguido de ativo e descanso para os filhotes. A natação e o descanso são importantes para as fêmeas pois exigem menos energia, já que precisam usá-la para atividades das quais a sobrevivência da espécie depende, como parir, amamentar e cuidar dos filhotes. Para os filhotes, o comportamento ativo é mais importante para o seu desenvolvimento motor e preparação para o processo migratório. Os eventos mais expressados por ambos fêmea e filhote foram exposições indefinidas, estas sendo duas vezes maior para os filhotes. Os filhotes apresentaram comportamentos aéreos em taxas maiores do que as fêmeas, o que denota a importância de tais comportamentos no auxílio ao desenvolvimento da coordenação e na aptidão motora e no fortalecimento da musculatura, melhorando a resistência para a migração. A taxa de ocorrência de eventos aéreos para as fêmeas foi geralmente mais baixa, provavelmente na tentativa de desencorajar os comportamentos ativos realizados pelos filhotes. Esses resultados reforçam a importância da área de estudo como área reprodutiva para a espécie. O número de baleias-franca está crescendo na área, bem como o potencial conflito com atividades humanas. Entender os padrões comportamentais dos pares fêmea-filhote de baleias-franca-austral no litoral de Santa Catarina podem servir como valiosas ferramentas para a elaboração de planos de manejo, contribuindo para a conservação da espécie no litoral brasileiro
The south central coast of Santa Catarina State is the most important breeding ground for southern right whales, Eubalaena australis, in Brazil. The aim of this study is to characterize the behavior pattern of mother-calf pairs that winter in this area, over ten breeding seasons (2003-2012). Land based observations were conducted from July to November, between 2003 and 2012, about six to seven times a week, between 6 a.m. and 5 p.m. Data were collected with the aid of binoculars Pentax 12x55 mm, compass, digital clock, and recorded in standardized field data sheets. Behavioral states (traveling, resting and playing) were recorded every five minutes and the frequency of events was recorded in each five minute interval. Traveling was the behavioral state that prevailed for both mother and calves, followed by resting and playing for mothers and followed by playing and resting for calves. Travelling and resting are important for mothers because they are less costly, since they need to use their energy to activities in which the survival of the species depends on, like giving birth, nursing and taking care of the calves. Playing is important for the calves to its motor development and its preparation for the migratory process. The most expressed events expressed by both mothers and calves were indefinite exposure, these being twice as high for the calves. Calves presented aerial behaviors at higher rates than their mothers, which denotes the importance of such behaviors in the aid of the development of motor skills coordination and in the muscles strengthening, improving resistance for migration. The aerial events rate of occurrence for mothers was generally lower, probably in an attempt to discourage the pranks conducted by the calves. These results reinforce the importance of the study area as a nursery ground for the species. The number of right whales is increasing in the area, as well as the potential for conflict with human activities. Understanding the behavioral patterns of southern right whale mother-calf pairs in Santa Catarina coast can serve as valuable tools for the formulation of management plans, contributing to the conservation of the species in the Brazilian coast.
Delgado, Delson Susana. "Relación entre el perfil del basamento en fiordos y canales y la morfoestructura regional en Norpatagonia". Tesis, Universidad de Chile, 2004. http://www.repositorio.uchile.cl/handle/2250/100513.
Pełny tekst źródłaHerrera, Osandón Mariajosé. "Geomorfologia de la cuenca del glaciar chico, campos de hielo sur, Chile Austral". Tesis, Universidad de Chile, 2005. http://repositorio.uchile.cl/handle/2250/100631.
Pełny tekst źródłaGueneley, Stéphanie. "Contribution à l'étude du cycle biogéochimique du silicium dans l'Océan Antarctique". Brest, 1988. http://www.theses.fr/1988BRES2031.
Pełny tekst źródłaAlonzo, Frédéric. "Stratégies reproductives des copépodes subantarctiques dominant l'écosystème pélagique côtier des Iles Kerguelen : Implications écologiques". Aix-Marseille 2, 2001. http://www.theses.fr/2000AIX22056.
Pełny tekst źródłaLo, Monaco Claire. "Etude du carbone anthropique dans l'Océan Indien Austral : Distribution et variabilité décennale". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2006. http://tel.archives-ouvertes.fr/tel-00121242.
Pełny tekst źródłaPereira, Janini. "Influência do gelo marinho antártico no setor austral sudoeste do Atlântico Sul". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/21/21132/tde-25062008-095930/.
Pełny tekst źródłaIn this work the interaction between Antarctic sea-ice and the South Atlantic ocean (austral and southwestern sectors) is investigated. To accomplish this satellite-observed sea-ice concentration (SIC) and a coupled model from NCAR-CCSM3 (National Center for Atmospheric Research - Community Climate System Model version 3) were employed. Three 150-year simulations, one each with the maximum (MAX), minimum (MIN) and average (control) SIC prescribed climatologies, were used to drive the CCSM3 run. The goal of the research is to evaluate the Weddell Sea and Brazil-Malvinas confluence (BMC) response to observed extremes in Antarctic sea-ice. This study focuses on annual, interannual and decadal timescales. The applied methodology uses correlation and spectrum analyses, as well as Empirical Orthogonal Functions (EOF) and Singular Value Decomposition (SVD). The annual mean behavior of oceanic variables showed sensibility to Antarctic sea-ice changes. The variability of SST and SSS anomalies showed for the sea-ice MIN experiment a spatial pattern that characterizes the cold regime of the Weddell Gyre, associate with low CDW intrusion. The response of the temperature variability, between sea-ice MAX and MIN scenarios, for the BMC region suggests that less Antarctic sea-ice produces a SST anomaly intensification in this region with a interannual cycle of the 2-3year and decadal cycle of the 25-year. The oceanic circulation in both study regions, related to positive SAM events, showed a intensification to less SIC influence.
Fabiano, Ezequiel Chimbioputo. "Demografia histórica e contemporânea de guepardos (Acinonyx jubatus) na Namíbia, África Austral". Pontifícia Universidade Católica do Rio Grande do Sul, 2013. http://hdl.handle.net/10923/5588.
Pełny tekst źródłaBackground: The contemporary genetic diversity of species and populations is a product of climatic oscillations over deeper timescales and/or anthropogenic factors over recent times. These forces caused alterations in the effective population size of fauna and flora, thus affecting not only their evolutionary potential but also species spatial distributions. Consequently, a need exists for assessing the historical demography of species at different population levels. The origin of the contemporary genetic diversity of cheetahs is thought to be the result of a severe decline around the Last Glacium Maximum (8,000 - 20,000 years ago, ya), followed by an expansion around the mid-Holocene ( 5,000 years) and a subsequent bottleneck within the past century due to a combination of anthropogenic factors and weather variability. Alternative hypotheses include that of a metapopulation structure and the persistence at a low effective size due to a high reproductive variance associated with a polygynous mating system. However, these three remain largely untested despite advances in molecular analytical tools over the past decades. Likewise, the effects of anthropogenic factors on population viability merit quantification as well as trends in abundance and density using robust surveying techniques. This study aims to contribute novel information on these aspects; information deemed of high significance for comprehensive conservation measures that do not underestimate the true risk of extinction the species is facing. First, we explored the historical demography of the largest free-ranging cheetah population over the past 60,000 years. Second, we assessed the population’s genetic viability and its sensitivity to perturbations on vital rates and uncertainties on current population size and carrying capacity estimates. Lastly, we assessed trends in density, abundance, and behavioural ecology aspects of cheetahs. Methods: To explore the historical demography, we stratified periods during the last 60,000 years and contrasted evolutionary models assuming stability, decline and expansion using approximate Bayesian computation methods. We estimated the population’s contemporary effective size using four genetic estimators and population viability analysis (PVA). Sensitivity analyses of the susceptibility of viability estimates to perturbations were also performed using a PVA approach. To estimate density and abundance, we used a combination of Bayesian spatial capture, recapture and non-spatial methods. Results: First, demographic scenarios indicated that the population has a complex demographic history, characterised by periods of decline intercalated with periods of stability with no signal of expansion contrived during the past 60,000 ya. The population seems to have been stable over the past 300 years. Additionally, scenarios modeled on abrupt reductions had low levels of support in relation to models assuming gradual reductions. Second, we found the present population to be viable, although susceptible to perturbations such as the proportion of breeding females, adult female survival rates, and uncertainties in current abundance estimates and on carrying capacity. These parameters also influenced the total population size. However, the direction of the impact was related to perturbation levels. Lastly, and mostly applicable for males, we observed density estimates of 5 to 20 km-3 that were largely similar across most of the six multi-year surveys. Furthermore, male cheetahs showed high site fidelity, utilising scent-marking locations for up to four consecutive years with possible temporal avoidance. Overall individuals displayed a nocturnal activity pattern. Discussion: First, the study shows that the population’s contemporary genetic diversity (and possibly that of other populations to which our population is genetically connected) is the result of a gradual decline, likely caused by fluctuations and reductions of suitable habitat due to Pleistocene and Holocene climatic oscillations, as well as recent increases in aridification in Namibia. Second, that the population viability is largely dependent on aspects related to females, and that threshold values seem to exist beyond which certain conservation actions may have a negative influence on viability. Lastly, male density seems to be regulated by home range dynamics, as density remained similar across surveys except during periods of social instability caused by vacant home ranges. The instability caused by removals may lead to higher reproductive variance. Conclusions: Overall, the study shows that a realistic estimate of the risk of extinction faced by this population requires an integration of results obtained with several analytical approached, and that long-term conservation plans should incorporate such a body of information. The observation that viability is susceptible to different biological and social factors highlights the relevance of this assessment, which is integrated to the other themes investigated in this study. In a broader context, the results presented here are potentially relevant for assessments targeting other species facing similar threats of extinction.
Contexto: A diversidade genética contemporânea de espécies e populações é resultante da interação entre aspectos ecológicos e biológicos das mesmas em relação aos efeitos de processos históricos naturais, bem como ao efeito atual dos humanos. Essas forças causaram alterações no tamanho efetivo da população de muitos elementos da fauna e flora, afetando não só os seus potenciais evolutivos, mas também suas distribuições geográficas. Conseqüentemente, existe uma necessidade de caracterizar a história demografica de espécies em diferentes níveis. A baixa diversidade genética contemporânea de guepardos é usualmente considerada como o resultado de um severo gargalo genético em torno do Último Máximo Glacial (8. 000 - 20. 000 anos atrás), seguido por endogamia, uma expansão em meados do Holoceno (5. 000 anos) e finalmente um gargalo durante o ultimo século devido a a uma combinação de fatores humanos e variações climáticas. Hipóteses alternativas incluem uma estrutura de metapopulação e persistência de tamanho efetivo baixo, devido à ocorrência de poliginia, gerando uma alta variância reprodutiva. Apesar dos avanços em ferramentas moleculares nas últimas décadas, estas hipóteses permanecem ainda largamente inexploradas. Da mesma forma, os efeitos de fatores humanos sobre a viabilidade da população, precisam ser quantificados, assim como é necessário determinar as tendências temporais em abundância e densidade utilizando robustas abordagens sistemáticas. Neste contexto, o objetivo primário deste estudo foi obter novas informações sobre estes aspectos, as quais são consideradas significantes para que medidas de conservação abrangentes sejam colocadas em prática. Especificamente, exploramos a historia demografica da maior população de guepardos ao longo dos últimos 60 mil anos. Segundo, avaliamos a viabilidade genética desta população e sua sensibilidade a perturbações e incertezas sobre o tamanho da população atual, bem como estimativas da sua capacidade suporte. Por fim, avaliamos as tendências em densidade e abundância, assim como certos aspectos ecológicos comportamentais de uma população local. Ferramentas: Métodos Bayesianos foram aplicados para avaliar e contrastar cenários evolutivos de estabilidade, declínio e de expansão em diferentes períodos nos últimos 60 mil anos. Para estimar o tamanho efetivo contemporâneo da população, foram utilizadas quatro estimativas genéticas e uma baseada em simulações de viabilidade. Simulações foram realizadas para avaliar a sensibilidade da estimativa de tamanho efectivo a perturbações nas taxas vitais, incertezas no tamanho da população e capacidade suporte. Por fim, o tamanho populacional de censo e a densidade populacional foram estimados através de métodos espaciais e não espaciais de captura-recaptura. Resultados: Primeiro, os cenários demográficos indicaram que a população tem uma história demográfica complexa, caracterizada por períodos de declínio populacional, intercalados por períodos de estabilidade, sem sinal de expansão detectado desde 60. 000 mil anos. Um sinal de estabilidade foi detetado para os ultimos 300 anos. Adicionalmente, cenários modelados que assumiram reduções abruptas tiveram taxas baixas de suporte em relação a modelos de redução gradual. Segundo, estimativas de tamanho efetivo baseadas em simulações indicaram que a população é viável, porém suscetível a perturbações como a proporção de fêmeas reprodutoras, as taxas de sobrevivência de adultos do sexo feminino, e incertezas em estimativas de abundância e de capacidade de suporte. O tamanho de censo da população também foi influenciado por estes parâmetros. No entanto, a influência em ambos os parâmetros é condicionada aos níveis de perturbações. Terceiro, as estimativas de densidade, principalmente de machos adultos, variaram entre 5 - 20 km-3 e foram semelhantes entre os levantamentos realizados no decorrer dos seis anos de amostragem. Os guepardos machos mostraram uma fidelidade de até quatro anos de uso consecutivo de sítios de marcação (scent-marking sites) dentro de suas áreas próprias, evidenciando também um padrão de atividade predominantemente noturno. Discussão: Primeiro, o estudo mostra que a diversidade genética contemporânea da população (e possivelmente de outras populações com as quais está geneticamente ligada) é resultante de um declínio gradual, provavelmente causado por flutuações e reduções de habitat adequado devidas a oscilações climáticas no Pleistoceno e Holoceno, bem como aumentos no nivel de aridez em tempos mais recentes na Namíbia. Segundo, que a viabilidade da população é em grande parte dependente de aspectos relacionados com fêmeas, e que parecem existir valores limiares além dos quais certas perturbações podem ter uma influência negativa sobre a viabilidade. Por último, a densidade de machos parece ser resultado da dinâmica das áreas de vida, visto que a densidade permaneceu semelhante, exceto durante os períodos de instabilidade social causada por áreas vagas. A instabilidade causada por remoções antropogênicas pode, portanto, levar a maior variância reprodutiva. Conclusões: O estudo indica que uma estimativa realista do risco de extinção desta população requer a integração de resultados obtidos por diversas abordagens analíticas, e que planos de conservação de longo prazo devem incluir tal conjunto de informações. A observação de que a viabilidade é sensível a diferentes fatores biológicos e sociais ressalta a importância desta avaliação, a qual se integra aos demais temas investigados neste estudo. De forma mais ampla, os resultados aqui apresentados são potencialmente relevantes para diversas outras espécies que enfrentam ameaças de extinção semelhantes.