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Item Underwater optics in sub-antarctic and antarctic coastal ecosystems(Public Library of Science (PLOS), 2016-05-04) Huovinen, Pirjo; Ramírez, Jaime; Gómez, Iván; Ban, SyuheiUnderstanding underwater optics in natural waters is essential in evaluating aquatic primary production and risk of UV exposure in aquatic habitats. Changing environmental conditions related with global climate change, which imply potential contrasting changes in underwater light climate further emphasize the need to gain insights into patterns related with underwater optics for more accurate future predictions. The present study evaluated penetration of solar radiation in six sub-Antarctic estuaries and fjords in Chilean North Patagonian region (39-44 degrees S) and in an Antarctic bay (62 degrees S). Based on vertical diffuse attenuation coefficients (K-d), derived from measurements with a submersible multichannel radiometer, average summer UV penetration depth (z(1%)) in these water bodies ranged 2-11 m for UV-B (313 nm), 4-27 m for UV-A (395 nm), and 7-30 m for PAR (euphotic zone). UV attenuation was strongest in the shallow Quempillen estuary, while Fildes Bay (Antarctica) exhibited the highest transparency. Optically non-homogeneous water layers and seasonal variation in transparency (lower in winter) characterized Comau Fjord and Puyuhuapi Channel. In general, multivariate analysis based on K-d values of UV and PAR wavelengths discriminated strongly Quempillen estuary and Puyuhuapi Channel from other study sites. Spatial (horizontal) variation within the estuary of Valdivia river reflected stronger attenuation in zones receiving river impact, while within Fildes Bay a lower spatial variation in water transparency could in general be related to closeness of glaciers, likely due to increased turbidity through ice-driven processes. Higher transparency and deeper UV-B penetration in proportion to UV-A/visible wavelengths observed in Fildes Bay suggests a higher risk for Antarctic ecosystems reflected by e.g. altered UV-B damage vs. photorepair under UV-A/PAR. Considering that damage repair processes often slow down under cool temperatures, adverse UV impact could be further exacerbated by cold temperatures in this location, together with episodes of ozone depletion. Overall, the results emphasize the marked spatial (horizontal and vertical) and temporal heterogeneity of optical characteristics, and challenges that these imply for estimations of underwater optics.Item Efecto de la aproximación de botes turísticos sobre la conducta de alerta y escape en colonias de pingüinos en el monumento natural islotes de Puñihuil(Universidad de Chile, 2009) Oetiker Hidalgo, María José; Cattan Ayala, Pedro; Facultad de Ciencias Veterinarias y Pecuarias; Escuela de Ciencias VeterinariasLas actividades como el ecoturismo tienen el potencial de generar alteraciones en las conductas habituales de la fauna silvestre, por lo que averiguar cómo ella responde a la presencia humana, así como establecer zonas de amortiguación entre humanos y animales es de gran importancia. Las conductas de alerta y escape en pingüinos son usadas como predictores de la perturbación humana e indicadores no invasivos de su tolerancia. El objetivo de esta memoria fue evaluar la respuesta conductual de S. humboldti y S. magellanicus en condiciones de reposo frente a la aproximación de botes con motor fuera de borda, así como las eventuales diferencias entre especies y la variación de las conductas de alerta y escape según el tamaño grapal de los pingüinos. No se encontraron diferencias significativas entre ambas especies al comparar las distancias de alerta, escape y la diferencia entre ambas o distancia de amortiguación. Tampoco se encontró interacción entre el tamaño grupal y especie. De los resultados se desprende que aquellos individuos que se encuentran solos o en pareja escapan a una mayor distancia que aquellos individuos que se encuentran en grupos de 5 o más individuos. Por el contrario, la zona de amortiguación es mayor en aquellos grupos que contienen cinco o más pingüinos, existiendo una alta correlación entre tamaño grupal y distancia de amortiguación. Estos datos pueden contribuir en el manejo a fin de resguardar la preservación de la vida silvestre, así como para la regulación de actividades ecoturísticas.Item Bioactive monoterpenes from antarctic Plocamium Cartilagineum(Sociedad Chilena de Química, 2013) Rovirosa, Juana; Soler, Agnes; Blanc, Vanessa; León, Rubén; San Martín, AurelioIn a chemical analysis of the red seaweed Plocamium cartilagineum collected in Antarctic Peninsula, four polyhalogenated monoterpenes were isolated. Their structures were established by spectroscopic techniques. Two of them are acyclic monoterpenes and the others are cyclic. We report the antimicrobial, insecticide and acaricide activities of compounds.Item Initial reconnaissance for a South Georgia ice core(Cambridge Universty Press, 2016-03-16) Mayewsky, P.A.; Kuli, A.; Casassa, Gino; Arévalo, M.; Dixon, D.A.; Grigholm, B.; Handley, M.J.; Hoffmann, H.; Introne, D.S.; Kuli, A.G.; Potocki, M.; Sneed, S.B.We present the first snow/ice chemistry and ice radar results ever collected from South Georgia as part of an initial reconnaissance with the ultimate goal of assessing the feasibility of a South Georgia ice core to reconstruct past climate in the South Atlantic. South Georgia is well situated to capture a record of past atmospheric chemical composition over the South Atlantic and of past variability in the position and intensity of the austral westerlies. The question is how well preserved an ice core record can be recovered from a region experiencing accelerated melting? The results presented in this paper offer only a preliminary step in determining the feasibility of future deep ice coring on South Georgia. However, this initial reconnaissance does provide some basic information including: the chemistry of the atmosphere over South Georgia relative to other Southern Hemisphere ice coring sites; the potential for preservation of ‘annual layers’ in old ice on the island; a possible age for deep ice in the region; and an estimate of glacier health in the lower elevation regions of the island.Item Ilaia(Instituto Antártico Chileno, 2015) Gallardo, Jorge; Espinoza, Pablo; Flores, Patricio; Muñoz, Patricio; Acevedo, Jorge; Barticevic, Elías; Gómez, Iván; Huovinen, Pirjo; Canales, Reiner; Hervé, Francisco; Martinic Beros, Mateo; Salazar, Juan Francisco; Edgardo, Vega; Canales, Reiner; Retamales Espinoza, José; Ruíz, Pablo; Quinán, René; Ojeda, Pamela; Runyard, Robert; Leppe, Marcelo; Barticevic, Elías; Vega, EdgardoItem Boletín Antártico Chileno(2004-05) Berguño Barnes, Jorge; Martinic Beros, Mateo; Eberhard, Patricio; Roselló, María José; Vera, Claudio; Vargas, Romeo; Torres, Daniel; Torres, Daniel; Valdenegro Vega, Victoria; Rubio, Wendy; Romero, Sebastián; Vallejos, Verónica; Valencia, José; Instituto Antártico Chileno; Ordóñez Kovacevic, Yasna; Berguño Barnes, Jorge; Julio Rocamora, Paulina; Ríos Villalón, Juan; Torres, DanielItem A preliminary study of trace metals and porphyrins in excreta of Gentoo penguins (Pygoscelis papua) at two locations of the Antarctic Peninsula(Facultad de Ciencias Veterinarias, Universidad Austral de Chile, 2012) Celis, J.; Jara, S.; González - Acuña, D.; Barra, R.; Espejo, W.Aunque las concentraciones de la mayoría de los elementos químicos en la Antártica son bajas en comparación con otras áreas del planeta, éstas se han ido incrementando con el tiempo debido al gran crecimiento de la población y desarrollo industrial de los países del Hemisferio Sur, lo cual podría estar afectando a especies vulnerables como los pingüinos. Se determinaron las concentraciones (peso seco) de arsénico (As), cadmio (Cd), mercurio (Hg) y plomo (Pb) y porfirinas (copro-, uro- y proto-) en heces de colonias de pingüinos Papua (Pygoscelis papua), colectadas en dos lugares de la península Antártica (O’Higgins y Videla). Se encontraron mayores (P < 0,05) niveles de Hg (7,55 ± 1,28 μg g-1) en las heces de colonias de pingüinos en O’Higgins, mientras que las colonias de pingüinos en Videla exhibieron mayores concentraciones de Cd (1,68 ± 0,71 μg g-1). Los pingüinos Papua de O’Higgins mostraron mayores (P < 0,05) niveles de copro- (1,81 ± 0,61 nmol g-1), uro- (1,74 ± 0,72 nmol g-1) y protoporfirinas (1,24 ± 0,46 nmol g-1), en directa relación con los mayores niveles de Hg y Pb medidos. Esto podría implicar que algunas colonias de pingüinos Papua de la península Antártica están propensas a desarrollar algunos efectos bioquímicos asociados a contaminación por metales traza. Estos resultados preliminares levantan inquietantes interrogantes acerca de la contaminación de origen antropogénico que estaría afectando áreas tan remotas como la Antártica.Item Robert Falcon Scott y su expedición al polo sur geográfico, 1910-1913. Visión desde cuatro diarios y dos revistas nacionales(Centro de Estudios Hemisféricos y Polares, 2016) Vásquez Mendoza, Karen; Cabrera Albornoz, CamiloLa presente investigación histórica tiene por objeto realizar una aproximación al contexto en que se hallaba la Antártica en los inicios del siglo XX, centrándose en la expedición del capitán Robert Falcon Scott y su propósito de llegar al Polo Sur Geográfico en el contexto de la Carrera Polar. Finalmente busca analizar, mediante una revisión de diarios (La Unión de Valparaíso, El Mercurio de Santiago, El Comercio y El Magallanes de Punta Arenas) y revistas (Zig-Zag de Santiago y Sucesos de Valparaíso) el seguimiento que realizó esta prensa sobre la expedición británica, con el fin de descubrir las diversas visiones allí existentes en relación a la temática.Item Trophic relationships of a subtidal fish assemblage in the Francisco Coloane coastal marine protected area, southern chilean patagonia(Taylor & Francis Group, 2018-02-27) Hüne, Mathias; Davis, Ernesto; Murcia, Silvia; Gutiérrez, David; Haro, DanielaA combination of stomach content and nitrogen (δ15N) and carbon (δ13C) stable-isotope analysis was used to assess the trophic interactions and feeding habits of three notothenioid coastal fish (Champsocephalus esox, Patagonotothen tessellata and Patagonotothen cornucola) and one exotic salmon species (Oncorhynchus tschawytscha) with diverse life habits (benthic and benthopelagic) in the Francisco Coloane Coastal Marine Protected Area, southern Chile. The stomach contents of C. esox were mainly fish; those of P. cornucola and O. tschawytscha were crustacean decapods, Munida gregaria. A cluster analysis on isotope data and stable-isotope Bayesian ellipses detected two different predator groups, one with benthopelagic habits (C. esox and O. tshawytscha) and one with benthic habits (P. cornucola and P. tessellata). These results were supported with similar isotopic trophic level of each group. We suggest that the exotic salmon O. tschawytscha is a generalist predator with a broad trophic niche that may compete with the native notothenioid C. esox, as both have equivalent trophic levels with substantial overlap. This preliminary study is the first on trophic relationships of a subtidal fish assemblage within a remote ecosystem of fjords and channels in Chile’s southern Patagonia.Item Ecophysiology of Antarctic vascular plants(Wiley & Sons and Scandinavian Society for Plant Physiology, 2002) Alberdi, Miren; Bravo, León A.; Gutiérrez, Ana; Gidekel, Manuel; Corcuera, Luis J.Most of the ice and snow-free land in the Antarctic summer is found along the Antarctic Peninsula and adjacent islands and coastal areas of the continent. This is the area where most of the Antarctic vegetation is found. Mean air temperature tends to be above zero during the summer in parts of the Maritime Antarctic. The most commonly found photosynthetic organisms in the Maritime Antarctic and continental edge are lichens (around 380 species) and bryophytes (130 species). Only two vascular plants, Deschampsia antarctica Desv. and Colobanthus quitensis (Kunth) Bartl., have been able to colonize some of the coastal areas. This low species diversity, compared with the Arctic, may be due to permanent low temperature and isolation from continental sources of propagules. The existence of these plants in such a permanent harsh environment makes them of particular interest for the study of adaptations to cold environments and mechanisms of cold resistance in plants. Among these adaptations are high freezing resistance, high resistance to light stress and high photosynthetic capacity at low temperature. In this paper, the ecophysiology of the two vascular plants is reviewed, including habitat characteristics, photosynthetic properties, cold resistance, and biochemical adaptations to cold.