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Sample records for west patagonia argentina

  1. Stereo Pair: Patagonia, Argentina

    Science.gov (United States)

    2000-01-01

    This view of northern Patagonia, near El Cain, Argentina shows complexly eroded volcanic terrain, with basalt mesas, sinkholes, landslide debris, playas, and relatively few integrated drainage channels. Surrounding this site (but also extending far to the east) is a broad plateau capped by basalt, the Meseta de Somuncura. Here, near the western edge of the plateau, erosion has broken through the basalt cap in a variety of ways. On the mesas, water-filled sinkholes (lower left) are most likely the result of the collapse of old lava tubes. Along the edges of the mesas (several locations) the basalt seems to be sliding away from the plateau in a series of slices. Water erosion by overland flow is also evident, particularly in canyons where vegetation blankets the drainage channels (green patterns, bottom of image). However, overland water flow does not extend very far at any location. This entire site drains to local playas, some of which are seen here (blue). While the water can reach the playas and then evaporate, what becomes of the eroded rock debris? Wind might excavate some of the finer eroded debris, but the fate of much of the missing bedrock remains mysterious.This cross-eyed stereoscopic image pair was generated using topographic data from the Shuttle Radar Topography Mission, combined with an enhanced Landsat 7 satellite color image. The topography data are used to create two differing perspectives of a single image, one perspective for each eye. In doing so, each point in the image is shifted slightly, depending on its elevation. When stereoscopically merged, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions.Landsat satellites have provided visible light and infrared images of the Earth continuously since 1972. SRTM topographic data match the 30-meter (99-foot) spatial resolution of most Landsat images and provide a valuable complement for studying the historic and growing Landsat data archive. The Landsat 7

  2. Anaglyph: Patagonia, Argentina

    Science.gov (United States)

    2000-01-01

    This view of northern Patagonia, near El Cain, Argentina shows complexly eroded volcanic terrain, with basalt mesas, sinkholes, landslide debris, playas, and relatively few integrated drainage channels. Surrounding this site (but also extending far to the east) is a broad plateau capped by basalt, the Meseta de Somuncura. Here, near the western edge of the plateau, erosion has broken through the basalt cap in a variety of ways. On the mesas, water-filled sinkholes (lower left) are most likely the result of the collapse of old lava tubes. Along the edges of the mesas (several locations) the basalt seems to be sliding away from the plateau in a series of slices. Water erosion by overland flow is also evident, particularly in canyons where vegetation blankets the drainage channels (bright patterns, bottom of image). However, overland water flow does not extend very far at any location. This entire site drains to local playas, some of which are seen here (dark lakes with bright shores). While the water can reach the playas and then evaporate, what becomes of the eroded rock debris? Wind might excavate some of the finer eroded debris, but the fate of much of the missing bedrock remains mysterious.This anaglyph was generated by first draping a Landsat Thematic Mapper image over a topographic map from the Shuttle Radar Topography Mission, then producing the two differing perspectives, one for each eye. When viewed through special glasses, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and the right eye with a blue filter.Landsat satellites have provided visible light and infrared images of the Earth continuously since 1972. SRTM topographic data match the 30-meter (99-foot) spatial resolution of most Landsat images and provide a valuable complement for studying the historic and growing Landsat data archive. The Landsat 7 Thematic Mapper image used here was provided to

  3. Diversity, distribution and floral specificity of tangle-veined flies (Diptera: Nemestrinidae in north west Patagonia, Argentina Diversidad, distribución y especificidad floral de nemestrínidos (Diptera en el noroeste de la Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    MARIANO DEVOTO

    2006-03-01

    Full Text Available Tangle-veined flies (Nemestrinidae constitute a primitive and rather widespread family among Diptera. The genus Trichophthalma occurs in Australia and South America and is the only one in the family with a typically Gondwanian, disjoint distribution. The ecology and distribution of most southern South American species of this genus remains virtually unknown. We studied the diversity, distribution and flower specificity of flower-visiting species of the genus Trichophthalma in the temperate forests of southern South America in ten sites along an east-west rainfall gradient (37-40°S on the eastern slope of the Andes. We recorded nine species of Trichophthalma, which showed an overlapped distribution along the gradient and different degrees of floral specificity. Three species are reported for Argentina for the first time and three are first recorded as flower visitors to the local flora. Our results show that while in southern Africa tangle-veined flies are engaged in highly specialized pollination interactions with long-tubed species, the Trichophthalma spp. of Patagonia share their flowers with a diverse and rather unspecialized visitor fauna among which several species of flies, bees and birds are presentLos nemestrínidos constituyen una familia de Dípteros primitiva y de amplia distribución. El género Trichophthalma se encuentra en Australia y Sudamérica y es el único en la familia con una distribución disjunta típicamente gondwánica. La ecología y distribución de la mayoría de las especies sudamericanas permanecen virtualmente desconocidas. Estudiamos la diversidad, distribución y especificidad floral de las especies del género Trichophthalma de los bosques templados del sur de Sudamérica en diez sitios ubicados a lo largo de un gradiente de precipitación este-oeste (37-40°S sobre la vertiente occidental de los Andes. Registramos nueve especies de Trichophthalma, las cuales mostraron una distribución superpuesta a lo largo

  4. Anaglyph: Basalt Cliffs, Patagonia, Argentina

    Science.gov (United States)

    2000-01-01

    Basalt cliffs along the northwest edge of the Meseta de Somuncura plateau near Sierra Colorada, Argentina show an unusual and striking pattern of erosion. Stereoscopic observation helps to clarify the landform changing processes active here. Many of the cliffs appear to be rock staircases that have the same color as the plateau's basaltic cap rock. Are these the edges of lower layers in the basalt or are they a train of slivers that are breaking off from, then sliding downslope and away from, the cap rock. They appear to be the latter. Close inspection shows that each stair step is too laterally irregular to be a continuous sheet of bedrock like the cap rock. Also, the steps are not flat but instead are little ridges, as one might expect from broken, tilted, and sliding slices of the cap rock. Stream erosion has cut some gullies into the cliffs and vegetation (appears bright in this infrared image) shows that water springs from and flows down some channels, but land sliding is clearly a major agent of erosion here.This anaglyph was generated by first draping a Landsat Thematic Mapper image over a topographic map from the Shuttle Radar Topography Mission, then producing the two differing perspectives, one for each eye. When viewed through special glasses, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and the right eye with a blue filter.Landsat satellites have provided visible light and infrared images of the Earth continuously since 1972. SRTM topographic data match the 30-meter (99-foot) spatial resolution of most Landsat images and provide a valuable complement for studying the historic and growing Landsat data archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM project by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center,Sioux Falls, South Dakota.Elevation data used in this image was

  5. A new burmagomphid dragonfly from the Eocene of Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Julián F. Petrulevičius

    2017-11-01

    Full Text Available A new burmagomphid anisopteran, Satelitala soberana gen. et sp. nov. is described from the lower Eocene of Laguna del Hunco, Patagonia, Argentina. The new genus is characterised by hindwing characters such as the subdiscoidal triangle not elongated; anal loop divided longitudinally; paranal cell divided longitudinally; five terminal cells between RP and MA; five terminal cells between MP and CuA; and obtuse angle between PsA and CuP+AA. Burmagomphid dragonflies were represented so far only by one specimen from the middle Cretaceous of Southeast Asia. This new record extends the distribution to Patagonia, to the Cenozoic, and also to paleolake deposits.

  6. Difilobotriasis humana en la Patagonia, Argentina Human diphyllobothriasis in Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Liliana Semenas

    1997-06-01

    Full Text Available OBJETIVO: El objetivo del trabajo fué detectar hospedadores humanos en la zona andino patagónica argentina, teniendo en cuenta las prácticas de pesca desportiva y la importancia de los salmónidos dentro de la zona. MATERIAL Y METODO: Entre 1986 y 1995 se implementaron Campañas de Información en los laboratorios de Análisis Clínicos de la región andinopatagónica argentina, destinadas a lograr una detección más eficiente de la difilobotriasis, a través de análisis coproparasitológicos. RESULTADOS: Adicionalmente, se confeccionaron planillas destinadas a recoger información sobre las características de la infección, del tratamiento y del paciente. Durante este período se detectaron 13 nuevos casos humanos, por identificación directa del parásito o por la presencia de huevos en materia fecal. Las características de las infecciones responden a las descriptas para el género Diphyllobothrium. CONCLUSIONES: En la región, los salmónidos son los peces predilectos en la pesca deportiva. Estos peces, frecuentemente parasitados con larvas, constituyen la principal fuente de contagio para el hombre al ser consumidos insuficientemente cocidos o ahumados en frío.OBJECTIVE: In view of the amateur fishing practices and the importance of salmonids in the region the study sets out to detect human hosts in the Andean-Patagonian zone. MATERIAL AND METHOD: Information campaigns were carried out by Clinical Analysis Laboratories of Andean Patagonia between 1986 and 1995 to detect diphyllobothriasis more efficiently by means of coproparasitological analysis. RESULTS: Further, forms were prepared for the collection of information about infection, treatment and the characteristics of the human host. During this period 13 new cases were registered either through direct identification of the parasite or through the presence of eggs in the faeces. The characteristics of infection are similar to those described for the genus Diphyllobothrium

  7. A new pentatomoid bug from the Ypresian of Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Julián F. Petrulevičius

    2016-12-01

    Full Text Available A new pentatomoid heteropteran, Chinchekoala qunita gen. et sp. nov. is described from the lower Eocene of Laguna del Hunco, Patagonia, Argentina. The new genus is mainly characterised by cephalic characters such as the mandibular plates surpassing the clypeus and touching each other in dorsal view; head wider than long; and remarkable characters related to the eyes, which are surrounded antero-laterally and posteriorly by the anteocular processes and the pronotum, as well as they extend medially more than usual in the Pentatomoidea. This is the first pentatomoid from the Ypresian of Patagonia and the second from the Eocene in the region, being the unique two fossil pentatomoids in Argentina.

  8. Stereo Pair: Basalt Cliffs, Patagonia, Argentina

    Science.gov (United States)

    2000-01-01

    Basalt cliffs along the northwest edge of the Meseta de Somuncura plateau near Sierra Colorada, Argentina show an unusual and striking pattern of erosion. Stereoscopic observation helps to clarify the landform changing processes active here. Many of the cliffs appear to be rock staircases that have the same color as the plateau's basaltic cap rock. Are these the edges of lower layers in the basalt or are they a train of slivers that are breaking off from, then sliding downslope and away from, the cap rock. They appear to be the latter. Close inspection shows that each stair step is too laterally irregular to be a continuous sheet of bedrock like the cap rock. Also, the steps are not flat but instead are little ridges, as one might expect from broken, tilted, and sliding slices of the cap rock. Stream erosion has cut some gullies into the cliffs and green vegetation shows that water springs from and flows down some channels, but landsliding is clearly a major agent of erosion here.This cross-eyed stereoscopic image pair was generated using topographic data from the Shuttle Radar Topography Mission, combined with an enhanced Landsat 7satellite color image. The topography data are used to create two differing perspectives of a single image, one perspective for each eye. In doing so, each point in the image is shifted slightly, depending on its elevation. When stereoscopically merged, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions.Landsat satellites have provided visible light and infrared images of the Earth continuously since 1972. SRTM topographic data match the 30-meter (99-foot) spatial resolution of most Landsat images and provide a valuable complement for studying the historic and growing Landsat data archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM project by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center,Sioux Falls, South Dakota

  9. Difilobotriasis humana en la Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Semenas Liliana

    1997-01-01

    Full Text Available OBJETIVO: El objetivo del trabajo fué detectar hospedadores humanos en la zona andino patagónica argentina, teniendo en cuenta las prácticas de pesca desportiva y la importancia de los salmónidos dentro de la zona. MATERIAL Y METODO: Entre 1986 y 1995 se implementaron Campañas de Información en los laboratorios de Análisis Clínicos de la región andinopatagónica argentina, destinadas a lograr una detección más eficiente de la difilobotriasis, a través de análisis coproparasitológicos. RESULTADOS: Adicionalmente, se confeccionaron planillas destinadas a recoger información sobre las características de la infección, del tratamiento y del paciente. Durante este período se detectaron 13 nuevos casos humanos, por identificación directa del parásito o por la presencia de huevos en materia fecal. Las características de las infecciones responden a las descriptas para el género Diphyllobothrium. CONCLUSIONES: En la región, los salmónidos son los peces predilectos en la pesca deportiva. Estos peces, frecuentemente parasitados con larvas, constituyen la principal fuente de contagio para el hombre al ser consumidos insuficientemente cocidos o ahumados en frío.

  10. Difilobotriasis humana en la Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Liliana Semenas

    1997-06-01

    Full Text Available OBJETIVO: El objetivo del trabajo fué detectar hospedadores humanos en la zona andino patagónica argentina, teniendo en cuenta las prácticas de pesca desportiva y la importancia de los salmónidos dentro de la zona. MATERIAL Y METODO: Entre 1986 y 1995 se implementaron Campañas de Información en los laboratorios de Análisis Clínicos de la región andinopatagónica argentina, destinadas a lograr una detección más eficiente de la difilobotriasis, a través de análisis coproparasitológicos. RESULTADOS: Adicionalmente, se confeccionaron planillas destinadas a recoger información sobre las características de la infección, del tratamiento y del paciente. Durante este período se detectaron 13 nuevos casos humanos, por identificación directa del parásito o por la presencia de huevos en materia fecal. Las características de las infecciones responden a las descriptas para el género Diphyllobothrium. CONCLUSIONES: En la región, los salmónidos son los peces predilectos en la pesca deportiva. Estos peces, frecuentemente parasitados con larvas, constituyen la principal fuente de contagio para el hombre al ser consumidos insuficientemente cocidos o ahumados en frío.

  11. Late cretaceous aquatic plant world in Patagonia, Argentina.

    Science.gov (United States)

    Cúneo, N Rubén; Gandolfo, María A; Zamaloa, María C; Hermsen, Elizabeth

    2014-01-01

    In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla) and a monocot (Araceae). Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae). Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form) and the eudicot angiosperm Nelumbo (Nelumbonaceae) are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae), ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America.

  12. Late cretaceous aquatic plant world in Patagonia, Argentina.

    Directory of Open Access Journals (Sweden)

    N Rubén Cúneo

    Full Text Available In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla and a monocot (Araceae. Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae. Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form and the eudicot angiosperm Nelumbo (Nelumbonaceae are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae, ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America.

  13. A late Jurassic pterosaur (Reptilia, Pterodactyloidea) from northwestern Patagonia, Argentina

    Science.gov (United States)

    Codorniú, Laura; Gasparini, Zulma; Paulina-Carabajal, Ariana

    2006-03-01

    A small to medium-sized pterodactyloid pterosaur (wingspan approximately 1.10 m) from the Upper Jurassic (middle-late Tithonian) marine deposits of the Vaca Muerta Formation of Patagonia (Los Catutos area, central Neuquén Province, Argentina) is reported. The specimen lacks the skull but constitutes a nearly complete postcranial skeleton, which includes cervical and dorsal vertebrae; a few thoracic ribs; both pectoral girdles; the left pelvic girdle; a proximal right wing (humerus, ulna, and radius) and metacarpal IV; a left wing that lacks only wing phalanx four; and both hindlimbs, the right one without the foot. Ontogenetic features suggest that the new fossil corresponds to a relatively mature individual, probably a subadult. Observed characters support its assignment to the Archaeopteroactyloidea, a basal clade within the Pterodactyloidea. This specimen is the second pterosaur from Los Catutos and the most complete Jurassic pterosaur so far known from South America.

  14. Stereo Pair: Inverted Topography, Patagonia, Argentina

    Science.gov (United States)

    2000-01-01

    by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center,Sioux Falls, South Dakota.Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise,Washington, DC.Size: 21.5 kilometers (13.4 miles) x 27.2 kilometers (16.9 miles) Location: 41.6 deg. South lat., 67.9 deg. West lon. Orientation: North toward upper left Image Data: Landsat bands 1,4,7 in blue, green, red Date Acquired: February 19, 2000 (SRTM), January 22, 2000 (Landsat)

  15. SRTM Anaglyph: Inverted Topography, Patagonia, Argentina

    Science.gov (United States)

    2000-01-01

    Resources Observation Systems (EROS) Data Center,Sioux Falls, South Dakota.Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise,Washington, DC.Size: 21.5 kilometers (13.4 miles) x 27.2 kilometers (16.9 miles) Location: 41.6 deg. South lat., 67.9 deg. West lon. Orientation: North toward upper left Image Data: Landsat band 7 (short infrared) Date Acquired: February 19, 2000 (SRTM), January 22, 2000 (Landsat)

  16. SRTM Stereo Pair: Meseta de Somuncura, Patagonia, Argentina

    Science.gov (United States)

    2000-01-01

    The Meseta de Somuncura is a semi-arid basalt plateau in northern Patagonia. This view of the northwestern part of the plateau, near Los Menucos, Argentina, shows numerous depressions where the upper basalt layers are missing or collapsed. Collapse occurs above voids in the underlying rock. These voids might have been caused by lava tubes carrying away molten lava from under the cooled and solidified surface of a lava flow. Alternatively, voids might result when ground water dissolves carbonate (limestone) or evaporite (salt) deposits that the lava may be covering.Many of the depressions have salty lakes. Light wind streaks downwind (eastward) from the lakes show that salt crystals blow off the lake beds during dry times. Some eroded sand and silt debris from the basalt must also blow downwind, but the degree to which wind plays a role in the erosion of the depressions is not clear.This cross-eyed stereoscopic image pair was generated using topographic data from the Shuttle Radar Topography Mission, combined with an enhanced Landsat 7satellite color image. The topography data are used to create two differing perspectives of a single image, one perspective for each eye. In doing so, each point in the image is shifted slightly, depending on its elevation. When stereoscopically merged, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions.Landsat satellites have provided visible light and infrared images of the Earth continuously since 1972. SRTM topographic data match the 30-meter (99-foot) spatial resolution of most Landsat images and provide a valuable complement for studying the historic and growing Landsat data archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM project by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center,Sioux Falls, South Dakota.Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the

  17. SRTM Anaglyph: Meseta de Somuncura, Patagonia, Argentina (Near Los Menucos)

    Science.gov (United States)

    2000-01-01

    The Meseta de Somuncura is a semi-arid basalt plateau in northern Patagonia. This view of the northwestern part of the plateau, near Los Menucos, Argentina, shows numerous depressions where the upper basalt layers are missing or collapsed. Collapse occurs above voids in the underlying rock. These voids might have been caused by lava tubes carrying away molten lava from under the cooled and solidified surface of a lava flow. Alternatively, voids might result when ground water dissolves carbonate (limestone) or evaporite (salt) deposits that the lava may be covering.Many of the depressions have salty lakes. Light wind streaks downwind (eastward) from the lakes show that salt crystals blow off the lake beds during dry times. Some eroded sand and silt debris from the basalt must also blow downwind, but the degree to which wind plays a role in the erosion of the depressions is not clear.This anaglyph was generated by first draping a Landsat Thematic Mapper image over a topographic map from the Shuttle Radar Topography Mission, then producing the two differing perspectives, one for each eye. When viewed through special glasses, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and the right eye with a blue filter.Landsat satellites have provided visible light and infrared images of the Earth continuously since 1972. SRTM topographic data match the 30-meter (99-foot) spatial resolution of most Landsat images and provide a valuable complement for studying the historic and growing Landsat data archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM project by the United States Geological Survey, Earth Resources Observation Systems (EROS) Data Center,Sioux Falls, South Dakota.Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same

  18. Patagonia

    DEFF Research Database (Denmark)

    O'Rourke, Dara; Strand, Robert

    2017-01-01

    This article examines the tensions that arise when Patagonia simultaneously pursues sustainability and quality objectives embedded within its mission statement: “Build the best product, cause no unnecessary harm, use business to inspire and implement solutions to the environmental crisis.” Specif......). This case explores the challenges Patagonia has faced and presents some creative solutions to them....

  19. Ancient parasites from endemic deer from "CUEVA PARQUE DIANA" archeological site, Patagonia, Argentina.

    Science.gov (United States)

    Beltrame, María Ornela; Tietze, Eleonor; Pérez, Alberto Enrique; Bellusci, Agustín; Sardella, Norma Haydée

    2017-05-01

    The narrow Andean-Patagonian temperate rainforest strip in the west of southern South America is inhabited by two endemic species of cervids, the southern pudu (Pudu puda) and the huemul (Hippocamelus bisulcus), both cataloged as near threatened and threatened species, respectively. One of the possible causes of their declined number is the susceptibility to livestock diseases. Significant zooarchaeological records of both deer have been found throughout the Holocene from Patagonia. The present contribution reports the first paleoparasitological results obtained from coprolites of endemic deer from the archeological site "Cueva Parque Diana," Neuquén Province, Argentina, and discusses the possible diseases found in ancient times. Thirty-four coprolites were fully processed, rehydrated, homogenized, sieved, subjected to spontaneous sedimentation, and examined by light microscopy. Thirty samples contained parasite remains. The presence of diverse parasitic diseases such as trematodioses, metastrongylosis, trichuriosis, strongylida gastroenteritis, dioctophymosis, and coccidiosis which could cause diseases in deer previous to the arrival of European livestock and the presence of zoonotic diseases in the hunters-gatherers and fishermen are discussed.

  20. Hepatitis Infecciosa Necrosante en ovinos Merino de la Patagonia argentina, parasitados con Thysanosoma actinioides Black Disease in Merino sheep infected with Thysanosoma actinioides in Patagonia Region, Argentina

    OpenAIRE

    Robles, C.A.; O.K. Kerbage; A.R. Moreira

    2000-01-01

    Se describe un brote de hepatitis infecciosa necrosante en un rebaño Merino de la Patagonia Argentina, en donde de 1200 ovejas mueren 80 de ellas (6,7%) en forma súbita. Los hallazgos de necropsia más llamativos fueron la gran cantidad de líquido en cavidades torácica y peritoneal, áreas de necrosis coagulativa en el parénquima hepático y la abundante cantidad de Thysanosoma actinioides en canalículos biliares y colédoco. En improntas de hígado se identificó Clostridium novyi mediante inmunof...

  1. Insectos acuáticos de la Meseta del Somuncura, Patagonia, Argentina. Inventario preliminar Aquatic insects from Somuncura plateau, Patagonia, Argentina. Preliminary inventory

    Directory of Open Access Journals (Sweden)

    Javier Muzón

    2005-12-01

    Full Text Available RESUMEN. Se brinda un inventario preliminar de los insectos acuáticos de la Meseta del Somuncura y su área de influencia (Patagonia, Argentina realizado sobre la base de colecciones y registros previos de especies pertenecientes a los órdenes Ephemeroptera, Odonata, Hemiptera (Heteroptera, Trichoptera, Diptera (familias Ceratopogonidae, Culicidae y Psychodidae y Coleoptera. Se han relevado diversos tipos de ambientes en 14 localidades. El número de especies registrado asciende a 78, agrupadas en 51 géneros y 26 familias, de las cuales 33 se citan por primera vez del área. De los taxa registrados 83% de los géneros corresponden a grupos de amplia distribución (neotropicales, americanos o cosmopolitas, mientras que 41% de las especies presentan una distribución patagónica o andina.ABSTRACT. A preliminary inventory of the aquatic insects from the Somuncura plateau and its area of influence (Patagonia, Argentina is presented. It was done on the basis of the study of collections and previous records of species belonging to the orders Ephemeroptera, Odonata, Hemiptera (Heteroptera, Trichoptera, Diptera (families Ceratopogonidae, Culicidae, and Psychodidae and Coleoptera. Different kinds of environments were surveyed in 14 localities. Seventy eigth species grouped in 51 genera and 26 families were registered, and 33 species are new records for the area. Eighty three % of the registered genera are widely distributed (neotropical, american or cosmopolitan, while 41 % of the species exhibit patagonic or andean distribution.

  2. Chondrichthyans of the San Matías Gulf, Patagonia, Argentina Los condrictios del Golfo San Matías, Patagonia, Argentina

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    María R PERIER

    2011-12-01

    Full Text Available The San Matías Gulf (SMG; 41°- 42° S; 64°- 65° W is the largest gulf in Northern Patagonia, Argentina. Up to date, the chondrichthyan fauna of this area has not been reported. Therefore, the aim of this work is to provide a list with species presence and biological characteristics of the chondrichthyans recorded in SMG during the last 30 years. A total of 13 sharks distributed in 11 families, 19 skates and rays distributed in six families, and one holocephalan have been so far recorded in SMG. From the zoogeographical point of view, this chondrichthyan fauna is a mixed assemblage of species typically found in the Argentinean and Magellanean Provinces. The holocephalan Callorhinchus callorynchus is the most landed chondricthyan of the local fishery. With it, five sharks and seven skates are also exploited.El Golfo San Matías (SMG; 41°- 42° S - 64°-65° O se encuentra ubicado en el norte de la Patagonia, Argentina. Hasta la fecha no se cuentan con reportes de la fauna de condrictios de esta zona. Por lo tanto, el objetivo de este trabajo es proporcionar una lista de la presencia y las características biológicas de los condrictios registrados en el SMG durante los últimos 30 años. Un total de 13 tiburones distribuidos en 11 familias, 19 batoideos distribuidos en seis familias y un holocefalo han sido reportados para la zona. Desde el punto de vista zoogeográfico, el SMG presenta un ensamble de especies pertenecientes a las Provincias Magallánica y Argentina. El holocefalo Callorhinchus callorynchus es el condrictio más desembarcado de la pesquería local. Con menor importancia son explotadas comercialmente, cinco especies de tiburones y siete de rayas.

  3. Late Paleozoic transpression in Buenos Aires and northeast Patagonia ranges, Argentina

    Science.gov (United States)

    Rossello, E. A.; Massabie, A. C.; López-Gamundí, O. R.; Cobbold, P. R.; Gapais, D.

    1997-12-01

    Paleozoic sediments are present in three regions in eastern central Argentina: (1) the Sierras Australes of Buenos Aires, (2) Sierras Septentrionales of Buenos Aires and (3) Northeast Patagonia. All of these deposits share a common deformational imprint imparted by late Paleozoic Gondwanan deformation. Exposures of these rocks are scattered, variably deformed, and isolated by younger sediments deposited in basins related to the Mesozoic through Tertiary opening of the South Atlantic such as the offshore Colorado Basin. The Sierras Australes of Buenos Aires outcrops are the best preserved. They are mostly located along the Sierras Australes foldbelt, with minor outliers distributed in the adjacent Claromec-basin. The Tunas Formation (early-early late? Permian) is the uppermost unit of the Pillahuincó Group (late Carboniferous-Permian) and is crucial to the understanding of the tectono-sedimentary evolution of the region during the late Paleozoic. The underlying units of the Pillahuincó Group (Sauce Grande, Piedra Azul and Bonete Formations) exhibit a depositional and compositional history characterized by glaciomarine sedimentation and postglacial transgression. They are also characterized by rather uniform quartz-rich compositions indicative of a cratonic provenance from the La Plata craton to the NE. In contrast, the sandstone-rich Tunas Formation has low quartz contents, and abundant volcanic and metasedimentary fragments; paleocurrents are consistently from the SW. Glassrich tuffs are interbedded with sandstone in the upper half of the Tunas Formation. The age of the deformation in the Sierras Australes is Permian and early-middle Triassic. This is based on metamorphic events indicated by formation of illite at 282 ± 3 Ma, 273 ± 8 Ma, 265 ± 3 Ma, and 260 ± 3 Ma ( {K}/{Ar} illite) in the Silurian Curamalal Group. Evidence of syntectonic magmatism is provided by a radiometric date of 245 ± 12 Ma ( {K}/{Ar} hornblende) for the López Lecube Granite

  4. Conifer woods from the Salamanca Formation (early Paleocene), Central Patagonia, Argentina: Paleoenvironmental implications

    Science.gov (United States)

    Ruiz, Daniela P.; Brea, Mariana; Raigemborn, M. Sol; Matheos, Sergio D.

    2017-07-01

    The main objective of the present work is to describe the first conifer assemblage of a mixed forest from the Danian Salamanca Formation at the Estancia Las Violetas locality (San Jorge Basin, Central Patagonia, Argentina), based on detailed descriptions of secondary xylem. Also, sedimentological description of the Estancia Las Violetas outcrops are made in order to understand the paleoenvironmental conditions under which paleocommunities developed. Six conifer woods are described and assigned to one Podocarpoxylon Gothan and three Cupressinoxylon Göppert species (including a new species). This is the first record of Patagonia forest where the conifer assemblage is dominated by Cupressinoxylon, associated with Podocarpaceae and palms (recorded as fruits), conforming a mixed forest with a floristic composition similar to present-day New Caledonia forests. Las Violetas fossil forest represent a parautochtonous community developed in a forested coastal setting, a tide-dominated estuary, at ∼51-50° S paleolatitudes of South America during the early-middle Danian.

  5. Polen y vegetación en la Patagonia extraandina argentina a 45º S

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    Burry, Lidia S.

    2005-12-01

    Full Text Available Modern pollen dispersal and deposition in relation to vegetation and environmental variables at 45° S was studied in Argentinian Patagonia east of the Andes to build a modern pollen model. This model will serve to identify modern pollen assemblages that are analog of past pollen assemblages. A west-to-east gradient of decreasing precipitation and increasing temperature determines four vegetation units: (1 grass steppe, (2 grass-bush steppe, (3 bush steppe and (4 bush-brush steppe. Pollen samples were analyzed by classification and ordination methods, and correlated to environmental variables. The steppes (a dominated by the functional type grass, (1 grass steppe, and (2 grass-bush steppe located in the more humid and cooler west end of the region were separated from the (b bush-dominated steppes (3 bush steppe and (4 bush-brush steppe occurring in the central and eastern parts of the region, where conditions are drier and warmer. Azonal communities were identified as halophytic bush steppes within different vegetation units along the west-east gradient. Environmental variables related to vegetation distribution are temperature and interannual precipitation variability associated with the precipitation gradient from the cordillera to the coast, and soil salinity in the case of azonal communities.Se investigó la relación de la dispersión-deposición del polen actual con la vegetación y con variables ambientales en la Patagonia extraandina argentina a 45° S con el fin de construir un modelo polínico actual. Este modelo servirá para identificar los conjuntos polínicos actuales que sean análogos de conjuntos polínicos fósiles. En la región hay un gradiente decreciente de precipitación y creciente de temperatura de oeste a este, que determina la existencia de diferentes unidades de vegetación: (1 estepa graminosa; (2 estepa graminosa-arbustiva; (3 estepa arbustiva y (4 estepa arbustiva-matorral. Los datos de polen de muestras de suelo

  6. Capacity building for freshwater insect studies in northern Patagonia, Argentina: DARWIN Initiative programme Biodiversidad de insectos acuáticos en Patagonia Norte, Argentina: programa Iniciativa DARWIN

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    Stephen J. Brooks

    2009-06-01

    Full Text Available This project was funded from September 2006 for three years by the British Government's Darwin Initiative programme. The focus of our project is the study of aquatic insects from Nahuel Huapi National Park (NHNP in Patagonia, Argentina. The park includes a wide range of wetlands, including montane streams, lowland lakes and marshes, distributed within temperate rainforest and arid steppe. The material will be identified and stored in a fully referenced and accessible collection at La Plata Museum and the Natural History Museum, London. Darwin Initiative funding has been used to equip a biodiversity laboratory at National Park Headquarters in Bariloche and also a field station at Puerto Blest. Information on the insect species in NHNP will be entered into a GIS database, together with a vegetation classification and wetland characteristics, to model freshwater insect data spatially and create a biodiversity database, the first of its kind in Patagonia. We hope that the experiences we gain during the project, the insect collections and databases, the publications, and the many other products, will be used to further enhance wetland conservation throughout Argentina and southern South America.Este proyecto fue financiado durante un período de tres años, desde septiembre de 2006 a través de la Iniciativa Darwin del gobierno Británico. El objetivo de este trabajo es el estudio de los insectos acuáticos del Parque Nacional Nahuel Huapi (PNNHP, Patagonia, Argentina. El parque incluye una gran variedad de hábitats que comprenden arroyos, ríos y lagos los cuales se distribuyen desde el bosque siempreverde frío, hasta la zona árida de estepa. Todo el material será identificado y depositado en las colecciones del Museo La Plata y el Museo de Historia Natural de Londres. Los fondos de la Iniciativa Darwin han sido utilizados para equipar un laboratorio de biodiversidad en las oficinas del PNNHP en Bariloche y la estación de investigación en

  7. "Jejenes" (Diptera: Simuliidae of Nahuel Huapi National Park, Patagonia, Argentina: Preliminary results "Jejenes" (Diptera: Simuliidae del Parque Nacional Nahuel Huapi, Patagonia, Argentina: Resultados preliminares

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    Luis M. Hernández

    2009-06-01

    Full Text Available The Simuliidae is a family of Diptera with approximately 2072 described species worldwide. The females of the majority of the species feed from vertebrates' blood, which makes them a significant plague that affects both men as well as cattle, birds, and other vertebrates. The objective of this paper is to create an inventory of Simuliidae and to reveal certain aspects of the biology and distribution of this family of aquatic insects in the Nahuel Huapi National Park. Moreover, information on the zoogeography of Simuliidae in Patagonia is provided. Five genera, 3 subgenera and 32 species Simuliidae are recorded from Patagonia: Cnesia (three spp., Cnesiamima (one sp., Gigantodax (14 spp., Paraustrosimulium (one sp., Simulium (Ectemnaspis (one sp., S. (Psaroniocompsa (one sp. and S. ( Pternaspatha (11 spp., At present, we have collected all five genera, one subgenus of Simulium (Pternaspatha, and 19 species of Simuliidae in the park, which amounts to 57% of the Simuliidae fauna in this area. Puerto Blest, a characteristic area of the High-Andean phytogeographical province (humid forest, showed the highest diversity of Simuliidae.Los simúlidos pertenecen a una familia de Diptera (Simuliidae con alrededor de 2.072 especies descritas a nivel mundial. Las hembras de la mayoría de las especies se alimentan con sangre de vertebrados, lo cual las convierte en importantes plagas que afectan tanto al hombre como al ganado, aves y otros vertebrados. Los objetivos de este trabajo son llevar a cabo un inventario de Simuliidae y dar a conocer algunos aspectos de la biología y la distribución de esta familia de insectos acuáticos en el Parque Nacional Nahuel Huapi, Argentina. Además, se proporciona información sobre la biogeografía de Simuliidae en la Patagonia. Cinco géneros, un subgénero y 32 especies de simúlidos han sido registrados para Patagonia: Cnesia (3 spp., Cnesiamima (1 sp., Gigantodax (14 spp., Paraustrosimulium (1 sp., Simulium

  8. Holocene Dynamics of Temperate Rainforests in West-Central Patagonia

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    Virginia Iglesias

    2018-01-01

    Full Text Available Analyses of long-term ecosystem dynamics offer insights into the conditions that have led to stability vs. rapid change in the past and the importance of disturbance in regulating community composition. In this study, we (1 used lithology, pollen, and charcoal data from Mallín Casanova (47°S to reconstruct the wetland, vegetation, and fire history of west-central Patagonia; and (2 compared the records with independent paleoenvironmental and archeological information to assess the effects of past climate and human activity on ecosystem dynamics. Pollen data indicate that Nothofagus-Pilgerodendron forests were established by 9,000 cal yr BP. Although the biodiversity of the understory increased between 8,480 and 5,630 cal yr BP, forests remained relatively unchanged from 9,000 to 2,000 cal yr BP. The charcoal record registers high fire-episode frequency in the early Holocene followed by low biomass burning between 6,500 and 2,000 cal yr BP. Covarying trends in charcoal, bog development, and Neoglacial advances suggest that climate was the primary driver of these changes. After 2,000 cal yr BP, the proxy data indicate (a increased fire-episode frequency; (b centennial-scale shifts in bog and forest composition; (c the emergence of vegetation-fire linkages not recorded in previous times; and (d paludification in the last 500 years possibly associated with forest loss. Our results therefore suggest that Nothofagus-Pilgerodendron dominance was maintained through much of the Holocene despite long-term changes in climate and fire. Unparalleled fluctuations in local ecosystems during the last two millennia were governed by disturbance-vegetation-hydrology feedbacks likely triggered by greater climate variability and deforestation.

  9. [Outbreak of histoplasmosis in province of Neuquén, Patagonia Argentina].

    Science.gov (United States)

    Calanni, Liliana María; Pérez, Rufina Ana; Brasili, Susana; Schmidt, Norma Graciela; Iovannitti, Cristina Adela; Zuiani, María Fernanda; Negroni, Ricardo; Finquelievich, Jorge; Canteros, Cristina Elena

    2013-01-01

    In Argentina, there are no reports of autochthonous cases of histoplasmosis in the southern regions of the country. To report a histoplasmosis outbreak in Zapala town, Province of Neuquén, Patagonia Argentina. We evaluated the clinical and epidemiological characteristics of 5 patients involved in the outbreak. Environmental studies were conducted to determine the source of infection. The genetic profile of Histoplasma capsulatum strains isolated from the index case (IC) were compared with clinical isolates from Argentinean patients not related to the outbreak, using RAPD-PCR with primers 1281-1283. The patients were residents of Zapala, and had not visited other geographical areas before. All patients had an influenza-like syndrome, and X-ray revealed disseminated micronodular images throughout the lung parenchyma. The IC needed specific antifungal therapy; the remaining 4 patients had mild symptoms, and did not require therapy. All of them had a good clinical outcome. Strains of H. capsulatum isolated from blood culture and lung biopsy of the IC showed a genetic profile different from other strains analyzed. The presence of the fungus in the environment was demonstrated by the detection of anti-Histoplasma antibodies in BALB/c mice inoculated with soil obtained in a culvert where workers had dug up earth after a landslide. This outbreak suggests the histoplasmosis endemic area is under the 38° S parallel. Patients from Neuquén, Patagonia Argentina, with compatible symptoms of histoplasmosis should be tested, regardless of their travel or exposure history. Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  10. Early Cretaceous Radiolarians from southernmost Patagonia, Argentina Radiolarios del Cretácico Temprano de la Patagonia Austral, Argentina

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    Chris Hollis

    2009-06-01

    Full Text Available A radiolarian assemblage found in the lowermost strata of the Río Mayer Formation, as exposed at Estancia La Federica in Santa Cruz Province, Argentina, is described. The biostratigraphic markers of this assemblage indicate a late Berriasian-early Barremian age (early Early Cretaceous. The radiolarians have faunal affinities with early Cretaceous assemblages reported from offshore northwestern Australia and the western Pacific, northeast of New Zealand. A cool-water affinity is suggested for the Patagonian assemblage. Ten meters below the levels with radiolarians sediments bearing continental palynomorphs are found. They are referred to the Springhill Formation of Berriasian to Valanginian age.Se presenta una asociación de radiolarios hallada en el sector inferior de la Formación Río Mayer expuesta en la Estancia La Federica en la provincia Santa Cruz, Argentina. Los elementos dignósticos de valor bioestratigráfico indican una edad Berriasiano tardío-Barremiano temprano (Cretácico Temprano inicial para este conjunto. Los radiolarios tienen afinidades faunísticas con asociaciones halladas costa afuera del noroeste de Australia y en el Pacífico occidental, al noreste de Nueva Zelanda. Se sugiere que la asociación de radiolarios patagónicos se desarrolló en aguas frías. Diez metros por debajo de los niveles portadores de radiolarios se hallan sedimentos continentales portadores de palinomorfos que fueron referidos a la Formación Springhill de edad Berriasiano-Valanginiano.

  11. Do native grazers from Patagonia, Argentina, consume the invasive kelp Undaria pinnatifida? ¿Pueden los pastoreadores nativos de Patagonia, Argentina, consumir al alga invasora Undaria pinnatifida?

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    S. Valeria Teso

    2009-06-01

    Full Text Available The invasive kelp Undaria pinnatifida (Phaeophyceae, Laminariales was first reported in Golfo Nuevo in 1992 and since then it has spread widely over more than 170 km, all along the northern Patagonian coast, Argentina. Field observations in the region have indicated the potential role of invertebrate grazers, like the sea urchins Arbacia dufresnii and Pseudechinus magellanicus and the gastropod Tegula patagonica, in controlling algal density. Laboratory experiments were conducted to ascertain whether, and if so, to what extent these grazers actually feed on the algae. The studied sea urchins fed on the alga, whereas the snail scraped off biofouling adhered to its surface. Higher densities of grazers were observed on the kelp during summer and might be attributed to increasing in metabolism with increasing temperature, and degradation of blades and sporophylls, which possibly increase their palatability.El alga invasora Undaria pinnatifida (Phaeophyceae, Laminariales fue reportada por primera vez en Golfo Nuevo en 1992, dispersándose ampliamente a lo largo de 170 km de costa en el norte de la Patagonia, Argentina. Observaciones de campo hechas en los erizos de mar Arbacia dufresnii y Pseudechinus magellanicus y en el gasterópodo Tegula patagonica evidenciaron que son posibles consumidores de Undaria pinnatifida en la población local. Se realizaron experimentos de laboratorio con el objetivo de probar si estos pastoreadores eran capaces de consumir el alga. Los erizos de mar estudiados consumen el alga, mientras que el gasterópodo ramonea los epibiontes presentes sobre su superficie. Altas densidades de ramoneadores fueron encontradas sobre el alga durante el verano y podrían ser atribuidas a un aumento del su metabolismo con el aumento de la temperatura y a la degradación de las láminas y esporofilos, lo cual posiblemente aumente la palatabilidad del alga.

  12. Polen de las Mieles de la Patagonia Andina (Chubut-Argentina Pollen of honeys from the Andean Patagonia (Chubut-Argentina

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    Alicia Forcone

    2006-07-01

    Full Text Available Se describen e ilustran mediante fotomicrografías tomadas con MO y MEB, 30 tipos polínicos, determinados en las mieles producidas en la región andina de Chubut (Patagonia Argentina. Los tipos morfológicos descriptos pertenecen a las siguientes familias: Alstroemeriaceae, Apiaceae, Buddlejaceae, Caryophyllaceae, Caprifoliaceae, Celastraceae, Clusiaceae, Convolvulaceae, Ericaceae, Elaeocarpaceae, Fabaceae, Fagaceae, Lamiaceae, Papaveraceae, Polemoniaceae, Polygalaceae, Proteaceae, Ranunculaceae, Rosaceae, Saxifragaceae, Solanaceae, Thymelaceae y Verbenaceae. La mayoría de los tipos polínicos descriptos fueron hallados en las mieles como polen de menor importancia o traza con excepción de Aristotelia chilensis y Escallonia sp., que alcanzaron la categoría de polen dominante, y de Lomatia hirsuta, hallada como polen secundario.Thirty pollen types identified in the honeys from the Andean region of Chubut are described and illustrated by means of LM and SEM photomicrographs. Pollen types belong to the following families: Alstroemeriaceae, Apiaceae, Buddlejaceae, Caryophyllaceae, Caprifoliaceae, Celastraceae, Clusiaceae, Convolvulaceae, Ericaceae, Elaeocarpaceae, Fabaceae, Fagaceae, Lamiaceae, Papaveraceae, Polemoniaceae, Polygalaceae, Proteaceae, Ranunculaceae, Rosaceae, Saxifragaceae, Solanaceae, Thymelaceae, and Verbenaceae. Most pollen types described were found in the honeys as minor important pollen or traces, except Aristotelia chilensis, Escallonia sp., which reached the category of dominant pollen, and Lomatia hirsuta, which was found as secondary pollen.

  13. “Jejenes” (Diptera: Simuliidae of Nahuel Huapi National Park, Patagonia, Argentina: Preliminary results

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    Luis M. HERNÁNDEZ

    2009-01-01

    Full Text Available Los simúlidos pertenecen a una familia de Diptera(Simuliidae con alrededor de 2.072 especies descritas a nivel mundial. Las hembras de la mayoría de las especies se alimentan con sangre de vertebrados, lo cual las convierte en importantes plagas que afectan tanto al hombre como al ganado, aves y otros vertebrados. Los objetivos de este trabajo son llevar a cabo un inventario de Simuliidae y dar a conocer algunos aspectos de la biología y la distribución de esta familia de insectos acuáticos en el Parque Nacional Nahuel Huapi, Argentina. Además, se proporciona información sobre la biogeografía de Simuliidae en la Patagonia. Cinco géneros, un subgénero y 32 especies de simúlidos han sido registrados para Patagonia: Cnesia (3 spp., Cnesiamima (1 sp., Gigantodax (14 spp., Paraustrosimulium (1 sp., Simulium (Ectemnaspis (1 sp., S. (Psaroniocompsa (1 sp. y Simulium (Pternaspatha (11 spp.. Hasta el presente, se han colectado los cinco géneros, un subgénero (Pternaspatha y 19 especies de Simuliidae en el PNNH, lo cual representa el 57% de la fauna de Simuliidae en esta área. La mayor diversidad de Simuliidae se encontró en Puerto Blest, zona característica del bosque de la provincia fitogeográfica Alto-Andina.

  14. Cretaceous Small Scavengers: Feeding Traces in Tetrapod Bones from Patagonia, Argentina

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    de Valais, Silvina; Apesteguía, Sebastián; Garrido, Alberto C.

    2012-01-01

    Ecological relationships among fossil vertebrate groups are interpreted based on evidence of modification features and paleopathologies on fossil bones. Here we describe an ichnological assemblage composed of trace fossils on reptile bones, mainly sphenodontids, crocodyliforms and maniraptoran theropods. They all come from La Buitrera, an early Late Cretaceous locality in the Candeleros Formation of northwestern Patagonia, Argentina. This locality is significant because of the abundance of small to medium-sized vertebrates. The abundant ichnological record includes traces on bones, most of them attributable to tetrapods. These latter traces include tooth marks that provde evidence of feeding activities made during the sub-aerial exposure of tetrapod carcasses. Other traces are attributable to arthropods or roots. The totality of evidence provides an uncommon insight into paleoecological aspects of a Late Cretaceous southern ecosystem. PMID:22253800

  15. A new species of Parapsectrocladius Cranston (Diptera: Chironomidae: Orthocladiinae) from Patagonia, Argentina.

    Science.gov (United States)

    Donato, Mariano; Mauad, Melina; Fuentes, María Cecilia

    2015-01-21

    Parapsectrocladius setosus sp. n. is described and figured as pupa and male imago, based on material collected in Patagonia, Argentina. The male of the new species groups with P. escondido Cranston & Añón Suárez by having the anal point tapering triangular; inferior volsella simple, rounded, without any dorsal ridge and apically blunt. It can be distinguished from P. escondido by the possession of strong setae on the inner margin of inferior volsella. New material of Parapsectrocladius belonging from several localities allows us to emend the generic diagnosis of the adult male, female and larva of Parapsectrocladius, discuss its phylogenetic position and to expand the geographic distribution of P. acuminatus Cranston, P. escondido and P. reissi. Cranston. 

  16. Marine pollution effects on the southern surf crab Ovalipes trimaculatus (Crustacea: Brachyura: Polybiidae) in Patagonia Argentina.

    Science.gov (United States)

    Lezcano, Aníbal Hernán; Rojas Quiroga, María Laura; Liberoff, Ana Laura; Van der Molen, Silvina

    2015-02-28

    We compared the carapace shape and thickness as well as the energy density of Ovalipes trimaculatus inhabiting areas comprising a gradient of marine pollution: high, moderate and undetected, in the Nuevo gulf (Patagonia Argentina). The carapace shape was evaluated by means of individual asymmetry scores (=fluctuating asymmetry) whereas the carapace thickness was assessed by measuring the carapace dry weight. The energy density was analyzed through its negative relationship with water content in muscle tissue. The individual asymmetry scores as well as the percentage of water content in muscle tissue were proportional to the marine pollution gradient, whereas the carapaces thickness did not differ among sampling sites. Our results are consistent with previous findings and demonstrate the direct effect of marine pollution on other taxa different from gastropods, cephalopods and polyplacophora and add to long-standing concerns about detrimental effects caused by marine pollution on the benthic community of the Nuevo gulf. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Foliar anatomy of Viola maculata growing in Parque Nacional Los Alerces, Chubut, Patagonia, Argentina

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    Chana Pilberg

    Full Text Available ABSTRACT Viola maculata Cav., Violaceae, grows in the underwood along the Los Andes mountain system from Neuquén to Tierra del Fuego and Islas Malvinas. It is also known as violeta amarilla or as pilundeu, and is used in popular medicine by the Mapuches as stimulant, in dermatology, and as a lavage in eye diseases. The aim of this work is to examine the morpho-anatomical traits of the leaves and petiole of V. maculata (collected at Parque Nacional Los Alerces, Patagonia, Argentina. Cross sections and scanning electron microscopy of leaves blade and petiole showed a simple organization with simple unicellular trichomes and cells containing tannins, and crystals of calcium oxalate mainly in the spongy parenchyma. As V. maculata is used in traditional medicine, the specification of the anatomical characters is relevant to describe the species.

  18. Insectos acuáticos de la Meseta del Somuncura, Patagonia, Argentina. Inventario preliminar

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    Javier MUZÓN

    2005-01-01

    Full Text Available Se brinda un inventario preliminar de los insectos acuáticos de la Meseta del Somuncura y su área de influencia (Patagonia, Argentina realizado sobre la base de colecciones y registros previos de especies pertenecientes a los órdenes Ephemeroptera, Odonata, Hemiptera (Heteroptera, Trichoptera, Diptera (familias Ceratopogonidae, Culicidae y Psychodidae y Coleoptera. Se han relevado diversos tipos de ambientes en 14 localidades. El número de especies registrado asciende a 78, agrupadas en 51 géneros y 26 familias, de las cuales 33 se citan por primera vez del área. De los taxa registrados 83% de los géneros corresponden a grupos de amplia distribución (neotropicales, americanos o cosmopolitas, mientras que 41% de las especies presentan una distribución patagónica o andina.

  19. Biodiversidad de Heteroptera (Hemiptera acuáticas y semiacuáticas de la Patagonia argentina Biodiversity of aquatic and semiaquatic Heteroptera (Hemiptera from Argentinean Patagonia

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    María Cecilia Melo

    2009-06-01

    Full Text Available Las Heteroptera acuáticas y semiacuáticas (infraórdenes Nepomorpha, Gerromorpha y Leptopodomorpha no presentan una alta diversidad específica en Argentina, hasta el momento se han registrado 208 especies. Carlos Berg en 1881, publica el primer trabajo que hace referencia a heterópteros de la Patagonia, en el que lista los insectos recolectados durante la Campaña del Desierto. Desde principios de la década del '60, las Heteroptera acuáticas han sido estudiadas principalmente por A.O. Bachmann y colaboradores. Hasta el momento, se han registrado 36 especies pertenecientes a las familias Corixidae, Notonectidae, Belostomatidae, Gelastocoridae, Naucoridae y Nepidae (Nepomorpha; Hydrometridae, Veliidae y Mesoveliidae (Gerromorpha, y Saldidae (Leptopodomorpha. La mayoría de estas especies extienden su distribución geográfica hacia el norte de la Argentina, excepto Sigara (Tropocorixa egbertae Hungerford, S. (T. trimaculata (Le Guillou, S. (T. vuriloche Bachmann, S. (T. forciceps (Spinola, Trichocorixa milicorum Bachmann (Corixidae, Notonecta (Paranecta virescens Blanchard, N. (P. fazi Hungerford, N. (P. vereertbruggheni Hungerford (Notonectidae, Pseudosaldula bergi (Haglund y P. paralia (Torres, P. angusta (Drake & Carvalho, P. sola (Drake & Carvalho, P. doeringi (Drake & Carvalho y Saldula differata Drake & Carvalho (Saldidae, que son exclusivas de la Patagonia. El conocimiento de la diversidad de Heteroptera acuáticas y semiacuáticas en la Patagonia es bueno y, por los datos recogidos, su estado de conservación es aceptable ya que aproximadamente el 40% de la especies encontradas en áreas naturales protegidas son exclusivas de la región y representan cerca del 40 % del número de especies exclusivas de la Patagonia.The aquatic and semiaquatic Heteroptera (infraorders Nepomorpha, Gerromorpha and Leptopodomorpha show a low diversity in Argentina; up to now 208 species have been recorded. In 1881 Carlos Berg provided the first reference

  20. Capacity building for freshwater insect studies in northern Patagonia, Argentina: DARWIN Initiative programme

    Directory of Open Access Journals (Sweden)

    Stephen J. BROOKS

    2009-01-01

    Full Text Available Este proyecto fue financiado durante un período de tres años, desde septiembre de 2006 a través de la Iniciativa Darwin del gobierno Británico. El objetivo de este trabajo es el estudio de los insectos acuáticos del Parque Nacional Nahuel Huapi (PNNHP, Patagonia, Argentina. El parque incluye una gran variedad de hábitats que comprenden arroyos, ríos y lagos los cuales se distribuyen desde el bosque siempreverde frío, hasta la zona árida de estepa. Todo el material será identificado y depositado en las colecciones del Museo La Plata y el Museo de Historia Natural de Londres. Los fondos de la Iniciativa Darwin han sido utilizados para equipar un laboratorio de biodiversidad en las oficinas del PNNHP en Bariloche y la estación de investigación en Puerto Blest. Toda la información de los insectos acuáticos y las distintas formaciones vegetales donde éstos se han encontrado, se incluirá en una base de datos (la primera de su tipo en Patagonia que utilizará la metodología GIS para analizar patrones de distribución de las especies en el parque. En estos momentos se están produciendo varias guías de campo para identificar los insectos acuáticos del PNNHP. Es nuestro deseo que los resultados obtenidos en este proyecto, contribuyan a la conservación de los sistemas acuáticos en Argentina y América del Sur

  1. INVITACIÓN AL GEOTURISMO. REFLEXIONES SOBRE GEODIVERSIDAD Y POTENCIAL GEOTURÍSTICO EN LA PATAGONIA ARGENTINA

    Directory of Open Access Journals (Sweden)

    María de la Paloma Martínez Fernandez

    2013-12-01

    Full Text Available Geotourism as a type of nature tourism comes to fill an empty field on the use of geological resources of the landscape in Argentina. With an approach sustained by the ideas and progresses achieved along the last decades about sustainable tourism, geosites and geoparks are getting a boost worldwide. However, in Argentina this concept has not being incorporated yet within public or private touristic policies, despite owning a valuable geodiversity both scientific or aesthetically. Based on a review of concepts and foreign experiences on the subject, this article analyses the possibilities and parameters for geotourism developing in Argentinean Patagonia.

  2. Nuevas citas de insectos acuáticos para la Meseta de Somuncurá, Patagonia, Argentina New records of aquatic insects from Somuncurá plateau, Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Javier Muzón

    2010-06-01

    Full Text Available Se brindan nuevas citas y localidades de los insectos acuáticos de la Meseta de Somuncurá y su área de influencia (Patagonia, Argentina, sobre la base de recolecciones de los órdenes Odonata (familias Coenagrionidae, Aeshnidae, Gomphidae y Libellulidae, Hemiptera (familias Corixidae y Notonectidae y Diptera (familias Ceratopogonidae y Culicidae. Se registran 47 especies (agrupadas en 20 géneros, de las cuales 25 se citan por primera vez para el área. De ellas, 20 representan nuevos registros para Somuncurá (incluso tres especies nuevas para la ciencia, cuatro nuevas para la Patagonia extra-andina y una para la Patagonia. Se mencionan por primera vez dos géneros para Somuncurá, uno de los cuales es nuevo para la Patagonia extra-andina. Asimismo, se esclarece la identidad de cinco especies citadas previamente. Teniendo en cuenta el inventario preliminar y bibliografía reciente, el número total de especies de insectos acuáticos registrados en la Meseta de Somuncurá asciende a 104, agrupadas en 53 géneros.On the basis of recently collected specimens belonging to Odonata (Coenagrionidae, Aeshnidae, Gomphidae, and Libellulidae, Hemiptera (Corixidae and Notonectidae and Diptera (Ceratopogonidae and Culicidae, new records and new localities of aquatic insects for the Somuncurá plateau and its area of influence (Argentinean Patagonia are provided. Forty seven species in 20 genera are recorded, 25 of which for the first time from the area. Of them, 17 represent new records from Somuncurá, four from extra-andean Patagonia, one from Patagonia and three species are new to science. Two genera are recorded for the first time from Somuncurá, one of which is new from extra-andean Patagonia. The identity of five species previously recorded is established. Taking into account the preliminary inventory and recent bibliography, the total number of aquatic insects registered from the Somuncurá plateau increases to 104 species, grouped in 53 genera.

  3. A Water Resources Management Model to Evaluate Climate Change Impacts in North-Patagonia, Argentina

    Science.gov (United States)

    Bucciarelli, L. F.; Losano, F. T.; Marizza, M.; Cello, P.; Forni, L.; Young, C. A.; Girardin, L. O.; Nadal, G.; Lallana, F.; Godoy, S.; Vallejos, R.

    2014-12-01

    Most recently developed climate scenarios indicate a potential future increase in water stress in the region of Comahue, located in the North-Patagonia, Argentina. This region covers about 140,000 km2 where the Limay River and the Neuquén River converge into the Negro River, constituting the largest integrated basins in Argentina providing various uses of water resources: a) hydropower generation, contributing 15% of the national electricity market; b) fruit-horticultural products for local markets and export; c) human and industrial water supply; d) mining and oil exploitation, including Vaca Muerta, second world largest reserves of shale gas and fourth world largest reserves of shale-oil. The span of multiple jurisdictions and the convergence of various uses of water resources are a challenge for integrated understanding of economically and politically driven resource use activities on the natural system. The impacts of climate change on the system could lead to water resource conflicts between the different political actors and stakeholders. This paper presents the results of a hydrological simulation of the Limay river and Neuquén river basins using WEAP (Water Evaluation and Planning) considering the operation of artificial reservoirs located downstream at a monthly time step. This study aims to support policy makers via integrated tools for water-energy planning under climate uncertainties, and to facilitate the formulation of water policy-related actions for future water stress adaptation. The value of the integrated resource use model is that it can support local policy makers understand the implications of resource use trade-offs under a changing climate: 1) water availability to meet future growing demand for irrigated areas; 2) water supply for hydropower production; 3) increasing demand of water for mining and extraction of unconventional oil; 4) potential resource use conflicts and impacts on vulnerable populations.

  4. Condiciones productivas y exigencias de calidad en la fruticultura de la Patagonia argentina

    Directory of Open Access Journals (Sweden)

    Belén Alvaro

    2013-01-01

    Full Text Available La producción alimentaria está regida, a partir de los años noventa, por requerimientos de calidad e inocuidad que modifican sustancialmente las condiciones productivas del eslabón primario, en el marco de una reestructuración del sistema agroalimentario mundial. El caso en estudio aborda la conformación social de la cadena frutícola localizada en el norte de la Patagonia argentina, donde estos requerimientos se formalizan, entre otros, en las buenas prácticas agrícolas, abordadas como dispositivos de control que interpelan y vuelven complejas las condiciones de reproducción social de los chacareros, como productores independientes en la cadena, con impactos en sus trayectorias vitales y productivas. Se consultaron fuentes secundarias, y se realizó el relevamiento primario de casos. Las conclusiones se inscriben en las tensiones entre configuraciones productivas locales y avances de los controles del capital concentrado.

  5. Modeling stream-aquifer interactions in a shallow aquifer, Choele Choel Island, Patagonia, Argentina

    Science.gov (United States)

    Rodríguez, Leticia B.; Cello, Pablo A.; Vionnet, Carlos A.

    2006-04-01

    A groundwater/surface-water interaction model was developed for the shallow alluvial aquifer of the Choele Choel Island in Patagonia, Argentina. In this semiarid climate, agriculture is sustained by an irrigation/drainage system. During the irrigation season, seepage losses through unlined distribution canals in irrigated fields contribute to elevated groundwater levels, jeopardizing fruit productivity in some areas. Moreover, high stream stages during the irrigation season interfere with groundwater drainage. The model utilized MODFLOW and its stream package, and was successfully calibrated for a historical irrigation season. Modeling results indicate that drainage through streams is significantly higher than drainage through artificial drains. The stream/aquifer relationship proved very responsive to water table rises caused by irrigation. This response manifested as changes in the gaining/losing character of stream reaches. A synthetic run aimed at isolating the effect of streamflow changes on groundwater levels showed that the effect of higher streamflows dissipates toward the interior of the island, disappearing completely at the island center. Even though some results were qualitative, the model helped to provide a better understanding of the coupled system to elucidate some of the causes of a rising water table on the island.

  6. Biodiversity of cold-adapted yeasts from glacial meltwater rivers in Patagonia, Argentina.

    Science.gov (United States)

    de García, Virginia; Brizzio, Silvia; Libkind, Diego; Buzzini, Pietro; van Broock, María

    2007-02-01

    The occurrence of culturable yeasts in glacial meltwater from the Frías, Castaño Overo and Río Manso glaciers, located on Mount Tronador in the Nahuel Huapi National Park (Northwestern Patagonia, Argentina) is presented. Subsurface water samples were filtered for colony counting and yeast isolation. The total yeast count ranged between 6 and 360 CFU L(-1). Physiologic and molecular methods were employed to identify 86 yeast isolates. In agreement with yeast diversity data from studies for Antarctic and Alpine glaciers, the genera Cryptococcus, Leucosporidiella, Dioszegia, Rhodotorula, Rhodosporidium, Mrakia, Sporobolomyces, Udeniomyces and Candida were found. Cryptococcus and Leucosporidiella accounted for 50% and 20% of the total number of strains, respectively. Among 21 identified yeast species, Cryptococcus sp. 1 and Leucosporidiella fragaria were the most frequent. The typically psychrophilic Mrakia yeast strain and three new yeast species, yet to be described, were also isolated. All yeast strains were able to grow at 5, 10, and 15 degrees C. Among yeast strains expressing extracellular enzymatic activity, higher proteolytic and lipolytic activities were obtained at 4 degrees C than at 20 degrees C.

  7. Biodiversidad de Heteroptera (Hemiptera acuáticas y semiacuáticas de la Patagonia argentina

    Directory of Open Access Journals (Sweden)

    María Cecilia MELO

    2009-01-01

    Full Text Available Las Heteroptera acuáticas y semiacuáticas (infraórdenes Nepomorpha, Gerromorpha y Leptopodomorpha no presentan una alta diversidad específica en Argentina, hasta el momento se han registrado 208 especies. Carlos Berg en 1881, publica el primer trabajo que hace referencia a heterópteros de la Patagonia, en el que lista los insectos recolectados durante la Campaña del Desierto. Desde principios de la década del ’60, las Heteroptera acuáticas han sido estudiadas principalmente por A.O. Bachmann y colaboradores. Hasta el momento, se han registrado 36 especies pertenecientes a las familias Corixidae, Notonectidae, Belostomatidae, Gelastocoridae, Naucoridae y Nepidae (Nepomorpha; Hydrometridae, Veliidae y Mesoveliidae (Gerromorpha, y Saldidae (Leptopodomorpha. La mayoría de estas especies extienden su distribución geográfica hacia el norte de la Argentina, excepto Sigara (Tropocorixa egbertae Hungerford, S. (T. trimaculata (Le Guillou, S. (T. vuriloche Bachmann, S. (T. forciceps (Spinola, Trichocorixa milicorum Bachmann (Corixidae, Notonecta (Paranecta virescens Blanchard, N. (P. fazi Hungerford, N. (P. vereertbruggheni Hungerford (Notonectidae, Pseudosaldula bergi (Haglund y P. paralia (Torres, P. angusta (Drake & Carvalho, P. sola (Drake & Carvalho, P. doeringi (Drake & Carvalho y Saldula differata Drake & Carvalho (Saldidae, que son exclusivas de la Patagonia. El conocimiento de la diversidad de Heteroptera acuáticas y semiacuáticas en la Patagonia es bueno y, por los datos recogidos, su estado de conservación es aceptable ya que aproximadamente el 40% de la especies encontradas en áreas naturales protegidas son exclusivas de la región y representan cerca del 40 % del número de especies exclusivas de la Patagonia.

  8. Caracterización de un proceso de biorremediación de hidrocarburos en deficiencia de nitrógeno en un suelo de Patagonia Argentina

    OpenAIRE

    A.J. Acuña; O.H. Pucci; G.N. Pucci

    2008-01-01

    La zona central de la Patagonia, Argentina, se encuentra sometida a explotación petrolera y sus suelos se caracterizan por ser deficientes en nitrógeno. Esto causaría un efecto negativo en los procesos de atenuación natural que se desarrollan en los suelos contaminados con hidrocarburos. El objeto de este estudio fue determinar cual es el efecto de la deficiencia de nitrógeno sobre la biodegradación de los hidrocarburos en un suelo de la Patagonia, Argentina. Se trabajó con tres microcosmos a...

  9. Caracterización de un proceso de biorremediación de hidrocarburos en deficiencia de nitrógeno en un suelo de la Patagonia Argentina

    OpenAIRE

    Acuña, Adrián Javier; Pucci Ceima, Oscar Héctor; Pucci Bissetta, Graciela Natalia

    2008-01-01

    La zona central de la Patagonia, Argentina, se encuentra sometida a explotación petrolera y sus suelos se caracterizan por ser deficientes en nitrógeno. Esto causaría un efecto negativo en los procesos de atenuación natural que se desarrollan en los suelos contaminados con hidrocarburos. El objeto de este estudio fue determinar cual es el efecto de la deficiencia de nitrógeno sobre la biodegradación de los hidrocarburos en un suelo de la Patagonia, Argentina. Se trabajó con tres micr...

  10. Mass Estimation of Santacrucian Sloths from the Early Miocene Santa Cruz Formation of Patagonia, Argentina

    National Research Council Canada - National Science Library

    Néstor Toledo; Guillermo Hernán Cassini; Sergio Fabián Vizcaíno; M. Susana Bargo

    Miocene deposits of the Santa Cruz Formation, Patagonia, comprise a diverse and excellently preserved vertebrate fauna, allowing detailed paleobiological and paleoecological studies based on three ecological parameters...

  11. Late Holocene environmental changes in a mesotidal estuary from Patagonia, Argentina

    Science.gov (United States)

    Espinosa, Marcela; Escandell, Alejandra; Velez Agudelo, Camilo

    2016-04-01

    Two sediment records from the lower valley of Negro River, Patagonia, Argentina (41°01´S; 62°47'W) spanning for the last 2000 cal yrs BP were analyzed according to diatoms and sediments contents. The river originates at the junction of the Neuquén and the Limay Rivers, Northern Patagonia, and discharges more than 1000 m3/s to the South Atlantic Ocean. Mesotidal conditions dominate at the inlet (2.95 m) affecting the lower valley (about 20 km) where salinity decreases drastically in the last 2 km. Fossil diatom assemblages and grain size were studied from two cores located at 1.5 km (Villarino site) and 12 km (Criadero site) from the inlet. Samples for modern diatom analyses were collected from the littoral zone at eleven sites along the river. Physical and chemical variables were quantified representing the maximum heterogeneity along the aquatic environment. Turbidity, salinity, conductivity, pH and temperature data were obtained in situ during summer and winter. In addition, a surface sediment sample was taken for grain size analysis and organic matter content, and water samples were taken to analyze nutrients and major ions following standard methods. The diatom content of modern sediment samples were studied in order to achieve ecological information useful as modern analogous for Patagonian rivers. Diatom zones were characterized by constrained incremental sum of squares cluster analysis (single linkage, Euclidean distance) in the fossil sequences. Fossil and modern diatom assemblages were compared with Detrended Correspondence Analysis (DCA). A total of 77 samples (modern and fossils) were analyzed and more than 200 taxa were identified. Diatom assemblages showed distinct abundance patterns in relation to salinity with a shift from communities dominated by marine/brackish taxa in lower sites to communities dominated by freshwater taxa in the middle and upper course of the river. The record of Criadero core (12 km from the inlet) began 2000 cal yrs BP with

  12. First paleoparasitological record of digenean eggs from a native deer from Patagonia Argentina (Cueva Parque Diana archaeological site).

    Science.gov (United States)

    María Ornela, Beltrame; Eleonor, Tietze; Alberto Enrique, Pérez; Norma Haydeé, Sardella

    2017-02-15

    Eggs representative of a digenean species were found in coprolites belonged to an endemic deer from Patagonia. Samples were collected from the archaeological site named "Cueva Parque Diana". This site is a cave located at the Lanín National Park, Neuquén Province, Argentina. The coprolites were dated from 2370±70 to 580±60 years B.P. The eggs were ellipsoidal, operculated, yellowish and thin-shelled. Measurements (n=65) ranged from 120.0 to 142.5 (133.2±6.53) μm long and 62.5 to 87.5 (72.6±6.15) μm wide. Eggs were well-preserved and were identified as belonged to Class Trematoda, Subclass Digenea, similar to those of Fasciola hepatica or with another species not identified at present from Patagonia. This is the first report of digenean eggs from ancient deer worldwide. The present study confirms the presence of representatives of digenean species in endemic deer from Patagonia in ancient times and the presence of a trematode disease prior to the arrival of European cattle. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. An Unusual New Theropod with a Didactyl Manus from the Upper Cretaceous of Patagonia, Argentina

    Science.gov (United States)

    Apesteguía, Sebastián; Smith, Nathan D.; Juárez Valieri, Rubén; Makovicky, Peter J.

    2016-01-01

    Background Late Cretaceous terrestrial strata of the Neuquén Basin, northern Patagonia, Argentina have yielded a rich fauna of dinosaurs and other vertebrates. The diversity of saurischian dinosaurs is particularly high, especially in the late Cenomanian-early Turonian Huincul Formation, which has yielded specimens of rebacchisaurid and titanosaurian sauropods, and abelisaurid and carcharodontosaurid theropods. Continued sampling is adding to the known vertebrate diversity of this unit. Methodology/ Principal Findings A new, partially articulated mid-sized theropod was found in rocks from the Huincul Formation. It exhibits a unique combination of traits that distinguish it from other known theropods justifying erection of a new taxon, Gualicho shinyae gen. et sp. nov. Gualicho possesses a didactyl manus with the third digit reduced to a metacarpal splint reminiscent of tyrannosaurids, but both phylogenetic and multivariate analyses indicate that didactyly is convergent in these groups. Derived characters of the scapula, femur, and fibula supports the new theropod as the sister taxon of the nearly coeval African theropod Deltadromeus and as a neovenatorid carcharodontosaurian. A number of these features are independently present in ceratosaurs, and Gualicho exhibits an unusual mosaic of ceratosaurian and tetanuran synapomorphies distributed throughout the skeleton. Conclusions/ Significance Gualicho shinyae gen. et sp. nov. increases the known theropod diversity of the Huincul Formation and also represents the first likely neovenatorid from this unit. It is the most basal tetatanuran to exhibit common patterns of digit III reduction that evolved independently in a number of other tetanuran lineages. A close relationship with Deltadromaeus from the Kem Kem beds of Niger adds to the already considerable biogeographic similarity between the Huincul Formation and coeval rock units in North Africa. PMID:27410683

  14. Fluid typing and tortuosity analysis with NMR-DE techniques in volcaniclastic reservoirs, Patagonia/Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Bustos, Ulises Daniel [Schlumberger Argentina S.A., Buenos Aires (Argentina); Breda, Eduardo Walter [Repsol YPF Comodoro Rivadavia, Chubut (Argentina)

    2004-07-01

    Alternative hydrocarbon-detection techniques are used to differentiate water from hydrocarbon where resistivity-based methods are difficult to apply, such as freshwater reservoirs and complex lithologies. One of these areas is represented by the complex volcaniclastic freshwater reservoirs in the Golfo San Jorge basin, Patagonia Argentina, where water and oil have often identical response on conventional logs. Some advances in hydrocarbon identification based on nuclear magnetic resonance (NMR) techniques were achieved in long T1 environments (very light oils, gas) in the Golfo San Jorge basin by previous NMR fluid typing methods. However, since medium to heavy oils are commonly present in these intervals, hydrocarbon detection by such techniques cannot be properly achieved. In addition, restricted diffusion phenomena recognized in these intervals, constitute further complications in fluid typing since its presence have similar response than native oil. To address this problem, a fluid characterization method using NMR Diffusion-Editing techniques and processing/interpretation with D-T2 maps in a suite of NMR measurements was applied. The technique allowed the detection and evaluation of restricted diffusion in these reservoirs, enabling better hydrocarbon characterization in a broad viscosity range (from light to heavy). The method also improved the petrophysical evaluation because restricted diffusion is related to tortuosity in the reservoir. Since the application of this innovative reservoir evaluation method, fluid prognosis vs well completion results was increased from around 68% to around 88% in Golfo San Jorge basin. Moreover, in some of these areas rates above 95% were recently achieved in 2004. (author)

  15. Environmental Niche Overlap between Common and Dusky Dolphins in North Patagonia, Argentina.

    Science.gov (United States)

    Svendsen, Guillermo Martín; Romero, María Alejandra; Williams, Gabriela Noemí; Gagliardini, Domingo Antonio; Crespo, Enrique Alberto; Dans, Silvana Laura; González, Raúl Alberto

    2015-01-01

    Research on the ecology of sympatric dolphins has increased worldwide in recent decades. However, many dolphin associations such as that between common dolphins (Delphinus delphis) and dusky dolphins (Lagenorhynchus obscurus) are poorly understood. The present study was conducted in the San Matías Gulf (SMG) ecosystem (North Patagonia, Argentina) where a high diet overlap among both species was found. The main objective of the present work was to explore the niche overlap of common and dusky dolphins in the habitat and temporal dimensions. The specific aims were (a) to evaluate the habitat use strategies of both species through a comparison of their group attributes (social composition, size and activity), and (b) to evaluate their habitat preferences and habitat overlap through Environmental Niche modeling considering two oceanographic seasons. To accomplish these aims, we used a historic database of opportunistic and systematic records collected from 1983 to 2011. Common and dusky dolphins exhibited similar patterns of group size (from less than 10 to more than 100 individuals), activity (both species use the area to feed, nurse, and copulate), and composition (adults, juveniles, and mothers with calves were observed for both species). Also, both species were observed travelling and feeding in mixed-species groups. Specific overlap indices were higher for common dolphins than for dusky dolphins, but all indices were low, suggesting that they are mainly segregated in the habitat dimension. In the case of common dolphins, the best habitats were located in the northwest of the gulf far from the coast. In the warm season they prefer areas with temperate sea surface and in the cold season they prefer areas with relatively high variability of sea surface temperature. Meanwhile, dusky dolphins prefer areas with steep slopes close to the coast in the southwestern sector of the gulf in both seasons.

  16. The early Miocene balaenid Morenocetus parvus from Patagonia (Argentina and the evolution of right whales

    Directory of Open Access Journals (Sweden)

    Mónica R. Buono

    2017-12-01

    Full Text Available Balaenidae (right and bowhead whales are a key group in understanding baleen whale evolution, because they are the oldest surviving lineage of crown Mysticeti, with a fossil record that dates back ∼20 million years. However, this record is mostly Pliocene and younger, with most of the Miocene history of the clade remaining practically unknown. The earliest recognized balaenid is the early Miocene Morenocetus parvus Cabrera, 1926 from Argentina. M. parvus was originally briefly described from two incomplete crania, a mandible and some cervical vertebrae collected from the lower Miocene Gaiman Formation of Patagonia. Since then it has not been revised, thus remaining a frequently cited yet enigmatic fossil cetacean with great potential for shedding light on the early history of crown Mysticeti. Here we provide a detailed morphological description of this taxon and revisit its phylogenetic position. The phylogenetic analysis recovered the middle Miocene Peripolocetus as the earliest diverging balaenid, and Morenocetus as the sister taxon of all other balaenids. The analysis of cranial and periotic morphology of Morenocetus suggest that some of the specialized morphological traits of modern balaenids were acquired by the early Miocene and have remained essentially unchanged up to the present. Throughout balaenid evolution, morphological changes in skull arching and ventral displacement of the orbits appear to be coupled and functionally linked to mitigating a reduction of the field of vision. The body length of Morenocetus and other extinct balaenids was estimated and the evolution of body size in Balaenidae was reconstructed. Optimization of body length on our phylogeny of Balaenidae suggests that the primitive condition was a relatively small body length represented by Morenocetus, and that gigantism has been acquired independently at least twice (in Balaena mysticetus and Eubalaena spp., with the earliest occurrence of this trait in the late

  17. Fe-Ni Micrometorites from Upper Jurassic Cañadon Asfalto Fm., Patagonia, Argentina

    Science.gov (United States)

    Matteini, M.; Hauser, N.; Cabaleri, N.; Silva Nieto, D.; Cuadros, F. A.; Reyes, S.

    2014-09-01

    Microspherules from an upper Jurassic sediments from Patagonia, show mineralogical, geochemical and textural features very similar to those reported for I-type micrometeorites whereas some spherules are interpreted as typical G-type micrometeorites.

  18. Tipología predial del sector productor de cerezas del sur de la Patagonia argentina Farm typology of the sweet cherry production sector of southern Argentinean Patagonia

    Directory of Open Access Journals (Sweden)

    E. Righi

    2011-06-01

    Full Text Available La identificación de tipologías prediales es una herramienta útil para sintetizar la diversidad intrínseca de cada sistema de producción y puede ser eficientemente usada para realizar una selección racional y metódica de las fincas representativas en el contexto de proyectos de investigación y extensión. Sin embargo, las metodologías que se utilizan más comúnmente para producir una tipología presentan algunas características que limitan su aplicación expeditiva para la selección de fincas piloto. El objetivo de este trabajo fue realizar una identificación cuantitativa y una caracterización de tipologías prediales, sobre la base de análisis multivariado de fincas productoras de cerezas en el sur de la Patagonia argentina. Se aplicó una metodología innovadora combinando escala multidimensional, análisis de conglomerados y análisis de porcentajes de semejanza, sobre la base de la cual se identificaron seis diferentes tipos de fincas. Las ventajas de este método para la selección de fincas representativas son mostradas y discutidas a través de la individuación de una finca piloto dentro de cada tipo.Farm typology identification is a useful tool to summarize the diversity that is intrinsic to every farming system and it can be efficiently used to carry out a rational and methodical selection of representative farms within the context of research and extension projects. However, the methodologies that are most commonly used to produce a typology present some features that limit its expeditious application for the selection of pilot farms. The objective of this study was to make a quantitative identification and characterization of farm typologies based on multivariate analysis of the farms of southern Argentinian Patagonia that grow sweet cherry. An innovative methodology which combines multidimensional scaling, cluster analysis and similarity percentages analysis was applied and six relevantly different farm types were

  19. A new Cheirolepidiaceae (Coniferales) from the Early Jurassic of Patagonia (Argentina): Reconciling the records of impression and permineralized fossils.

    Science.gov (United States)

    Escapa, Ignacio; Leslie, Andrew

    2017-02-01

    Plants preserved in different fossil modes provide complementary data concerning the paleobiology and evolutionary relationships among plant groups. New material from the Early Jurassic of Patagonia shows the importance of combining these sources of information, as we describe the first compression/impression fossils of Pararaucaria, a genus of the extinct conifer family Cheirolepidiaceae previously known from permineralized fossils. These fossils extend the temporal range of this genus and may allow its wider recognition in the fossil record. We studied fossil plants from the Early Jurassic (Pleinsbachian-Toarcian) locality of Taquetrén in Patagonia, Argentina using standard paleobotanical preparation and description techniques. Pararaucaria taquetrensis consists of isolated ovuliferous scales and small seed cones with helically arranged bract-scale complexes attached to scale-leaf foliage. Bract-scale complexes consist of separated bracts and ovuliferous scales with two seeds and three broad distal lobes. Pararaucaria taquetrensis represents the oldest known Cheirolepidiaceae seed cones from the Southern Hemisphere, and this material highlights the importance of compression and impression fossils in understanding the distribution of fossil taxa. This material also suggests that Cheirolepidiaceae cone scales can be easily confused with those of another common conifer family, the Araucariaceae, which has important implications for accurately understanding Mesozoic conifer diversity and paleoecology. © 2017 Botanical Society of America.

  20. Sistemas de Conversores Fluidodinámicos de Energías Alternativas para la Patagonia Argentina

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    Carlos Labriola

    2016-12-01

    Full Text Available La UNPA-UACO comenzó a estudiar el tema de Energía Oceánica y sus conversores con el PI 29 B 125 del 2010: “Análisis de Sistemas de Conversores Fluidodinámicos de Energía Renovable para la Patagonia Austral de Argentina”. Luego en el 2014 se comienza el PI 29 B 163: “Sistemas Conversores Fluido-dinámicos de Energía Renovable para la Patagonia, Argentina”. Este proyecto analiza los recursos oceánicos de las corrientes marinas y undimotriz a macroescala y además se utilizaran modelos desarrollados de conversores de energía de las corrientes marinas y de las olas para estudio y posterior dimensionamiento de prototipos de aplicación para dichas fuentes. Durante el 2014 el becario se propone para estudiar el recurso de las mareas en Río Gallegos y determinación de ubicación de un futuro prototipo en la Ría de Rio Gallegos. El presente informe detalla el trabajo desarrollado durante el 2015 en lo que respecta a estudio del recurso mareomotriz y posible localización de prototipo de turbina hidrocinética flotante para la Ría de Río Gallegos, santa Cruz, Argentina.

  1. UN TERRITORIO POSIBLE EN LA REPÚBLICA IMPOSIBLE. EL CORONEL SAROBE Y LOS PROBLEMAS DE LA PATAGONIA ARGENTINA

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    Pedro Navarro Floria

    2012-01-01

    Full Text Available El proceso de formación territorial de los Estados latinoamericanos tiene uno de sus nudos problemáticos en la integración de sus espacios marginales. La nacionalización de la Patagonia argentina es un ejemplo claro de ese problema. En la década de 1930 diversas voces señalan que la incorporación de ese amplio y rico territorio al cuerpo de la nación sigue estando pendiente. El coronel Sarobe, representativo del sector profesionalista del ejército argentino, hizo el mejor análisis disponible sobre los problemas de la Patagonia, que aún se mantiene vigente en muchos aspectos. A la crítica de las políticas ensayadas hasta entonces, agrega la propuesta de un rol activo del Estado en favor de la colonización y de la autonomía política de la región.

  2. Sexual dimorphism in the mandible of the armadillo Chaetophractus villosus (Desmarest, 1804) (Dasypodidae) from northern Patagonia, Argentina.

    Science.gov (United States)

    Squarcia, S M; Sidorkewicj, N S; Camina, R; Casanave, E B

    2009-05-01

    The aim of this study was to study the sexual dimorphism in adult Chaetophractus villosus (Desmarest, 1804), from northern Patagonia, Argentina. Eight mandibular traits were measured in 37 males and 34 females. Univariate and multivariate morphometric analysis were applied to the data set. Results showed that C. villosus was sexually dimorphic, with higher absolute values corresponding to females. The total length of the mandible was the most important variable to discriminate sexes, followed by the height at the level of the last tooth and body length. The percentages of sex discrimination were high, as they were when a new sample (17 males, 13 females) was tested. Females have larger mandibles than males independently of their larger cranial size. They also showed a higher degree of correlation between variables, suggesting a more stable shape for the mandible than in males.

  3. Whole-genome sequence of Corynebacterium pseudotuberculosis PAT10 strain isolated from sheep in Patagonia, Argentina.

    Science.gov (United States)

    Cerdeira, Louise Teixeira; Pinto, Anne Cybelle; Schneider, Maria Paula Cruz; de Almeida, Sintia Silva; dos Santos, Anderson Rodrigues; Barbosa, Eudes Guilherme Vieira; Ali, Amjad; Barbosa, Maria Silvanira; Carneiro, Adriana Ribeiro; Ramos, Rommel Thiago Jucá; de Oliveira, Rodrigo Santos; Barh, Debmalya; Barve, Neha; Zambare, Vasudeo; Belchior, Silvia Estevão; Guimarães, Luis Carlos; de Castro Soares, Siomar; Dorella, Fernanda Alves; Rocha, Flavia Souza; de Abreu, Vinicius Augusto Carvalho; Tauch, Andreas; Trost, Eva; Miyoshi, Anderson; Azevedo, Vasco; Silva, Artur

    2011-11-01

    In this work, we report the complete genome sequence of a Corynebacterium pseudotuberculosis PAT10 isolate, collected from a lung abscess in an Argentine sheep in Patagonia, whose pathogen also required an investigation of its pathogenesis. Thus, the analysis of the genome sequence offers a means to better understanding of the molecular and genetic basis of virulence of this bacterium.

  4. Contribución al conocimiento de los Crisópidos de Coquimbo, Patagonia y Tierra del Fuego (Argentina, Chile (Insecta, Neuroptera, Chrysopidae

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    Monserrat, V. J.

    2005-12-01

    Full Text Available New data on the morphology, distribution and biology of five species of green-lacewings (Insecta, Neuroptera, Chrysopidae collected from samplings made in Patagonia, Tierra del Fuego and Coquimbo (Argentina, Chile are given. The general morphology and the preimaginal stages of Ungla argentina (Navás, 1911, Ungla binaria (Navás, 1922 and Chrysopodes (Neosuarius porterina (Navás, 1910 are described. This last species and Chrysoperla defreitasi Brooks, 1994 are recorded from Argentina for the first time.

    Se anotan nuevos datos sobre la morfología, distribución y biología de cinco especies de crisópidos (Insecta, Neuroptera, Chrysopidae capturadas durante los muestreos realizados en Patagonia, Tierra del Fuego y Coquimbo (Argentina, Chile. Se describen los estadios juveniles y los adultos de Ungla argentina (Navás, 1911, Ungla binaria (Navás, 1922 y Chrysopodes (Neosuarius porterina (Navás, 1910. Esta última especie y Chrysoperla defreitasi Brooks, 1994 se citan por primera vez de Argentina.

  5. Ñ irihuau: Explotación de hidrocarburos y conflicto social en las inmediaciones de Bariloche (Patagonia, Argentina

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    Guido Galafassi

    2014-06-01

    Full Text Available En el año 2008, el gobierno de la provincia de Río Negro (Patagonia, Argentina licitó y adjudicó a la Unión Transitoria de Empresas (ute YPF-Pluspetrol el área petrolera Ñirihuau para trabajos de exploración y eventual explotación de hidrocarburos. La iniciativa suscitó un importante proceso de movilización social, por cuanto el bloque concesionado lindaba con el Parque Nacional Nahuel Huapi y se ubicaba dentro de la reserva de biosfera Andino Norpatagónica. Asimismo, la zona es soporte de otras actividades económicas incompatibles con el proyecto y comprende territorios ancestrales reivindicados por comunidades indígenas mapuche. En el siguiente estudio de caso analizaremos el diseño y la implementación de esta política, focalizándonos en las peculiares características del área Ñirihuau y los cuestionamientos y estrategias seguidas por quienes se opusieron a la concesión. Hacia el final, pondremos este análisis en contexto, y lo relacionaremos con la situación de la industria hidrocarburífera argentina.

  6. Spatial distribution, feeding and length–mass relationships of Diamphipnopsis samali (Plecoptera, Diamphipnoidae in a North Patagonia Andean stream, Argentina

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    Guillermo H. OMAD

    2015-01-01

    Full Text Available RESUMEN. Fueron estudiados algunos aspectos de la biología y ecología (patrones de distribución espacial, hábitos alimenticios y relación largo-masa de una población de Diamphipnopsis samali en un arroyo de primer orden que atraviesa un bosque exótico de pino en el centro-norte de Patagonia (Chubut, Argentina. Dos series de muestreos fueron realizados durante períodos de aguas altas y aguas bajas. Toda la información fue tratada con ANOVAS de dos factores y efectos fijos para evaluar diferencias significativas. El análisis de las piezas bucales de D. samali indica que corresponden a un tipo intermedio entre el tipo carnívoro y herbívoro-detritívoro. El contenido estomacal muestra que esta especie se alimenta de hifas fúngicas y madera, aunque en los estadios tempranos se encuentran restos de insectos. No se hallaron diferencias significativas en la alimentación entre períodos de aguas altas y aguas bajas, sin embargo, existieron diferencias significativas entre la dieta de larvas grandes y pequeñas. Fue clara la preferencia por el sustrato tronco y cascada, y también significativamente diferente entre los tipos pozón y corredera. No hubo diferencias significativas en la elección de hábitat entre los períodos de aguas bajas y aguas altas. Esta especie endémica de Patagonia parece estar bien adaptada a la presencia de un bosque ripario exótico, utilizando los troncos caídos como alimento y refugio.

  7. The sedimentology and dynamics of crater-affiliated wind streaks in western Arabia Terra, Mars and Patagonia, Argentina

    Science.gov (United States)

    Rodriguez, J.A.P.; Tanaka, K.L.; Yamamoto, A.; Berman, D.C.; Zimbelman, J.R.; Kargel, J.S.; Sasaki, S.; Jinguo, Y.; Miyamoto, H.

    2010-01-01

    Wind streaks comprise recent aeolian deposits that have been extensively documented on Venus, Earth and Mars. Martian wind streaks are among the most abundant surface features on the planet and commonly extend from the downwind margins of impact craters. Previous studies of wind streaks emerging from crater interior deposits suggested that the mode of emplacement was primarily related to the deposition of silt-sized particles as these settled from plumes. We have performed geologic investigations of two wind streaks clusters; one situated in western Arabia Terra, a region in the northern hemisphere of Mars, and another in an analogous terrestrial site located in southern Patagonia, Argentina, where occurrences of wind streaks emanate from playas within maar craters. In both these regions we have identified bedforms in sedimentary deposits on crater floors, along wind-facing interior crater margins, and along wind streaks. These observations indicate that these deposits contain sand-sized particles and that sediment migration has occurred via saltation from crater interior deposits to wind streaks. In Arabia Terra and in Patagonia wind streaks initiate from crater floors that contain lithic and evaporitic sedimentary deposits, suggesting that the composition of wind streak source materials has played an important role in development. Spatial and topographic analyses suggest that regional clustering of wind streaks in the studied regions directly correlates to the areal density of craters with interior deposits, the degree of proximity of these deposits, and the craters' rim-to-floor depths. In addition, some (but not all) wind streaks within the studied clusters have propagated at comparable yearly (Earth years) rates. Extensive saltation is inferred to have been involved in its propagation based on the studied terrestrial wind streak that shows ripples and dunes on its surface and the Martian counterpart changes orientation toward the downslope direction where it

  8. Cuatro nuevas especies del género Liolaemus (Iguania: Liolaemidae, pertenecientes al grupo boulengeri, de la Patagonia, Argentina

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    Abdala, Cristian Simón

    2003-12-01

    Full Text Available Se describen cuatro nuevas especies del género Liolaemus, pertenecientes al grupo boulengeri, caracterizado por la presencia de un parche femoral de escamas agrandadas en la parte posterior del fémur. Una especie fue colectada en el sur de la provincia de Neuquén y las otras tres en el suroeste, centro y este de la provincia de Río Negro, en la Patagonia Argentina. Dentro del grupo las nuevas especies están relacionadas fenéticamente a Liolaemus boulengeri. Se estudiaron 98 caracteres morfológicos externos, referidos principalmente a caracteres de lepidosis, patrón de coloración y proporciones corporales, corrientemente estudiados en Liolaemus. Las diferencias más significativas entre estas especies y Liolaemus boulengeri se dan principalmente en el patrón de coloración y en algunos caracteres de escamación. Estas especies ocupan parte de las tres regiones patagónicas que se diferencian con base en la orografía y vegetación asociada. Las nuevas especies del centro y suroeste de la provincia de Río Negro, soportan grandes diferencias de temperatura diarias y estacionales. Las cuatro especies que se describen aquí se alimentan principalmente de insectos. Four new species of Liolaemus are described from the Patagonia region of southern Argentina. One species was collected in southern Neuquén Province and the other three are from Río Negro Province. Each of the new species has a patch of enlarged scales on the posterior surface of the thighs, indicating their relationship to members of the boulengeri group. Within this group, the four new species are morphologically most similar, and may be most closely related to, Liolaemus boulengeri. A total of 98 external morphological characters, principally squamation, color pattern, and body proportions, were recorded for these new members of the boulengeri group and compared with those for Liolaemus boulengeri. Significant differences between the new species and Liolaemus boulengeri were

  9. Caracterización de las principales pesquerías del golfo San Jorge Patagonia, Argentina Characterization of the main fisheries in San Jorge Gulf, Patagonia, Argentina

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    María Eva Góngora

    2012-03-01

    Full Text Available En el golfo San Jorge se desarrollan varias actividades económicas de relevancia, entre ellas dos pesquerías industriales: la pesquería de merluza común (Merluccius hubbsi Marini, 1933 y la pesquería de langostino patagónico (Pleoticus muelleri Bate, 1888, ambas se solapan espacial y temporalmente. En la pesquería de merluza del golfo San Jorge opera una flota fresquera de altura, compuesta por unas 20 embarcaciones, y una flota costera, compuesta por unas 30 embarcaciones. En esta pesquería se pesca alrededor del 10% de lo capturado en el stock sur de merluza. En la pesquería de langostino del golfo San Jorge opera una flota congeladora tangonera compuesta por 80 embarcaciones, responsable de más del 75% de los desembarques de langostino realizados en la República Argentina. Ambas pesquerías tienen como principal problema la captura incidental de merluza, en una de sus principales áreas de cría. En el presente trabajo se describe el manejo actual en las pesquerías del golfo San Jorge, el cual consiste principalmente en cierres espaciales y temporales para la pesca de langostino, y zonificaciones por estrato de flota para la merluza. En ninguna de las dos pesquerías descriptas se han tomado medidas que reduzcan eficazmente la captura incidental.In San Jorge Gulf, several important economic activities are developed, including two industrial fisheries: hake (Merluccius hubbsi Marini, 1933 and Argentine red shrimp (Pleoticus muelleri Bate, 1888. Both overlap spatially and temporally. The San Jorge Gulf hake fishery consists of a high-seas ice trawler fleet (n = 20 fishing vessels and a coastal fleet (n = 30 fishing vessels. These fisheries capture about 10% of the catch of the southern hake stock. The Argentine red shrimp fishery consists of a double-beam trawler fleet with 80 freezer vessels, responsible for more than 75% of shrimp landings in Argentina. The main problem of both fisheries is the bycatch of hake in one of its

  10. Avifauna (Passeriformes of Santa Cruz province, Patagonia (Argentina: annotated list of species Avifauna (Passeriformes de la provincia de Santa Cruz, Patagonia (Argentina: lista comentada de especies

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    Carlos Aquiles Darrieu

    2009-06-01

    Full Text Available The birds (Passeriformes of Santa Cruz province, Argentina, are analyzed based on three main sources: specimens housed in the Museo Argentino de Ciencias Naturales of Buenos Aires (MACN, in the Félix de Azara Collection, Buenos Aires (CFA, in the Museo de La Plata, La Plata (MLP, in the Fundación Miguel Lillo, Tucumán (FML and in the National Museum of Natural History, Washington (USNM. The data were obtained from bibliographical citations which include precise localities and from field observations. A list of 75 species belonging to 13 families is included. First records with precise localities are provided for five species. New localities are cited for 64 species.En el presente trabajo se aporta una lista comentada de todas las especies de aves Passeriformes registradas en la provincia de Santa Cruz. Los ejemplares de colección pertenecen al Museo Argentino de Ciencias Naturales y a la Colección Félix de Azara, ambos de Buenos Aires, al Museo de La Plata, a la Fundación Miguel Lillo de Tucumán y al National Museum of Natural History, Washington. Los datos fueron obtenidos de la literatura, del análisis de especimenes de museos y de observaciones de campo. Esto nos permitió incluir un total de 75 especies pertenecientes a 13 familias. Cinco de ellas no presentaban registros concretos para la provincia, aportándose nuevas localidades para otras 64.

  11. Influence of crude oil contamination on the bacterial community of semiarid soils of Patagonia (Argentina)

    Energy Technology Data Exchange (ETDEWEB)

    Pucci, O.H.; Bak, M.A.; Peressutti, S.R.; Alvarez, H.M. [Univ. Nacional de la Patagonia, Facultad de Ciencias Naturales C.E.I.M.A., Comodoro Rivadavia (Argentina); Klein, I.; Haertig, C.; Wuensche, L. [UFZ - Umweltforschungszentrum Leipzig-Halle GmbH, Sektion Umweltmikrobiologie, Leipzig (Germany)

    2000-07-01

    Autochthonous bacteriocenoses in semiarid soils in Patagonia were found to be capable of rapidly adapting to high contamination with crude oil. This adaptation at community level is due to the selective enrichment of hydrocarbon-utilizing bacteria always present in these soils. Immediately after a heavy contamination with crude oil, the autochthonous bacteriocenosis contained about 28% hydrocarbon-utilizing bacteria which could be classified into eight ecotypes with characteristic metabolic profiles. Mainly n-alkanes were used as growth substrates of representative strains. After seven months' exposure to crude oil, the bacteriocenosis consisted almost entirely of hydrocarbon-utilizing bacteria. At least fourteen ecotypes were distinguishable, and the majority of representative strains were able to metabolize a broad spectrum of aliphatic and aromatic hydrocarbons. Corresponding to the significant alteration of the physiological diversity, drastic changes to the taxonomic diversity were also found. Whereas at the beginning of the study the autochthonous bacteriocenoses were dominated by Gram-positive genera of the Actinomycetales (Dietzia, Gordona, Nocardia, Rhodococcus, Streptomyces) with high ecological potency, after just two months' exposure to crude oil, Gram-negative bacteria (especially Pseudomonas stutzeri) became predominant within the hydrocarbon-utilizing bacteriocenoses accompanied by some Gram-positive genera of the Actinomycetales with a significantly lower abundance. These findings underline the importance of Pseudomonas and some genera of Actinomycetales for processes of natural attenuation and the technically supported in situ bioremediation of soil polluted by crude oil in Patagonia. (orig.)

  12. Selected contributions from the 9th International Conference on Tidal Sedimentology, November 2015, Puerto Madryn, Patagonia, Argentina: an introduction

    Science.gov (United States)

    Scasso, Roberto A.; Cuitiño, José I.

    2017-08-01

    This special issue of Geo-Marine Letters presents selected contributions from the 9th International Conference on Tidal Sedimentology held on 17-19 November 2015 in Puerto Madryn, Chubut Province, Patagonia, Argentina. The guest editors are the conference organizers Roberto A. Scasso and José I. Cuitiño. Gerardo M. Perillo was the head of the Scientific Committee. The conferences on tidal sedimentology have been traditionally held every 4 years. However, only 3 years separated the last conference held in Caen (France, 2012) from this conference. Increasing numbers of contributions and the growing interest in tidal sedimentation have been the reasons for shortening the inter-conference period. The 2015 conference served as a discussion forum focusing on advances in modern and ancient tidal sedimentation at different locations worldwide. The papers presented in this Special Issue provide a selective view of the latest research results, the main topics dealing with tidal hydrodynamics and sediment transport, tidal coastal morphodynamics, modern and ancient tidal sedimentation, geotechnical processes in tidal environments, and tidal basins, facies and reservoirs.

  13. Levels of essential and toxic elements in Porphyra columbina and Ulva sp. from San Jorge Gulf, Patagonia Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Perez, Adriana Angela [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina); Farias, Silvia Sara [Comision Nacional de Energia Atomica, Gerencia de Tecnologia y Medio Ambiente, Buenos Aires (Argentina); Strobl, Analia Mabel [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina); Perez, Laura Beatriz [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina); Lopez, Clara Magdalena [Catedra de Toxicologia y Quimica Legal, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Pineiro, Adriana [Catedra de Toxicologia y Quimica Legal, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Roses, Otmaro [Catedra de Toxicologia y Quimica Legal, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Fajardo, Maria Angelica [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina)]. E-mail: copipat@sinectis.com.ar

    2007-04-15

    Baseline concentration levels of As, B, Ca, Cd, Cr, Cu, Co, Fe, Mg, Mn, Mo, Ni, P, Pb, Se, V, and Zn were determined for Porphyra columbina and Ulva sp. collected from three locations along San Jorge Gulf, in Patagonia Argentina. Elements were quantified by inductively coupled plasma-optical emission spectrometry, with the exception of lead and cadmium in some samples which were determined by electrothermal atomic absorption spectrometry. Three stations with different exposure degree to human activities, Bahia Solano, the mouth of Arroyo La Mata stream and Punta Maqueda, were selected as sampling points. The results showed a wide range of metal retention capacity between the two studied species. Regarding the levels of pollutants found in the researched sites, Punta Maqueda seemed to be less influenced by anthropogenic activities than the other two sites except for Cd. Taking into account their toxicities seasonal variations in Pb and Cd levels were studied in both algae in Punta Maqueda. Maximum concentrations of Cd (9.8 {mu}g g{sup -1} dry wt.) were observed in P. columbina during winter, and maximum levels of Pb (0.82 {mu}g g{sup -1} dry wt.) were detected in Ulva sp. during summer. Legislative and health safety aspects were evaluated for Cd and Pb.

  14. Reproductive biology of Sympterygia bonapartii (Chondrichthyes: Rajiformes: Arhynchobatidae in San Matías Gulf, Patagonia, Argentina

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    María L. Estalles

    2017-04-01

    Full Text Available ABSTRACT This study estimates and analyses the reproductive parameters and cycle of Sympterygia bonapartii in San Matías Gulf, northern Patagonia, Argentina. A total of 827 males and 1,299 females were analysed. Males ranged from 185 to 687 mm of total length (TL and females from 180 to 742 mm TL. Sexual dimorphism was detected; females were larger, heavier, exhibited heavier livers, wider discs and matured at lager sizes than males. Immature females ranged from 180 to 625 mm TL, maturing females from 408 to 720 mm TL, mature ones from 514 to 742 mm TL and females with egg capsules from 580 to 730 mm TL. Immature males ranged from 185 to 545 mm TL, maturing ones from 410 to 620 mm TL and mature males from 505 to 687 mm TL. Size at which 50% of the skates reached maturity was estimated to be 545 mm TL for males and 594 mm TL for females. According to the reproductive indexes analysed, S. bonapartii exhibited a seasonal reproductive pattern. Mating may occur during winter-early spring and the egg-laying season, during spring and summer.

  15. Iron-bearing minerals of a rupestrian painting from the Manantial Solís site, Cardiel Lake, Patagonia, Argentina

    Science.gov (United States)

    Duarte Cavalcante, Luis Carlos; Ferraro, Lorena; Hugon, Paulette; Soares Meneses Lage, Maria Conceição; Fabris, José Domingos

    2017-11-01

    The archaeological site Manantial Solís is located on shores of the Cardiel Lake, Santa Cruz Province, Patagonia, Argentina. The main characteristic of this site is the occurrence of 251 rupestrian paintings, namely abstract figures, anthropomorphic and zoomorphic motifs, painted in different hues of red, but also in yellow, orange, pink, violet and white; these paintings are often formed by overlapping pictorial motifs. The basaltic rock-wall supporting these graphisms has been naturally degraded and, as a consequence, covered with saline efflorescence. The chemical and mineralogical analyses of a micro-sample from a red rupestrian painting were made in the laboratory by (i) energy dispersive X-ray fluorescence; (ii) CHN elemental analysis and (iii) 57Fe transmission Mössbauer spectroscopy at 298 K and 110 K, in an effort to identify the main iron-bearing minerals composing the painting pigments. The stratigraphy of the paint layer was investigated on a polished cross-section. From the Mössbauer spectra of this red painting, two sextets assignable to hematite ( α Fe2O3) were identified. The Fe3+ central doublet is assumed to be due to superparamagnetic phases, more likely as iron (oxyhydr)oxides (likely including some goethite, α FeOOH) in very small particles and paramagnetic iron in the crystalline structure of aluminosilicates. The Fe2+ doublet was interpreted as being due to the basalt rock support of this prehistoric painting.

  16. Late Cretaceous paleosols as paleoclimate proxies of high-latitude Southern Hemisphere: Mata Amarilla Formation, Patagonia, Argentina

    Science.gov (United States)

    Varela, Augusto N.; Raigemborn, M. Sol; Richiano, Sebastián; White, Tim; Poiré, Daniel G.; Lizzoli, Sabrina

    2018-01-01

    Although there is general consensus that a global greenhouse climate characterized the mid-Cretaceous, details of the climate state of the mid-Cretaceous Southern Hemisphere are less clearly understood. In particular, continental paleoclimate reconstructions are scarce and exclusively derived from paleontological records. Using paleosol-derived climofunction studies of the mid- to Upper Cretaceous Mata Amarilla Formation, southern Patagonia, Argentina, we present a reconstruction of the mid-Cretaceous climate of southern South America. Our results indicate that at 60° south paleolatitude during the Cenomanian-Santonian stages, the climate was subtropical temperate-warm (12 °C ± 2.1 °C) and humid (1404 ± 108 mm/yr) with marked rainfall seasonality. These results are consistent with both previous estimations from the fossil floras of the Mata Amarilla Formation and other units of the Southern Hemisphere, and with the previous observations of the displacement of tropical and subtropical floras towards the poles in both hemispheres. The data presented here show a more marked seasonality and slightly lower mean annual precipitation and mean annual temperature values than those recorded at the same paleolatitudes in the Northern Hemisphere.

  17. New cases of human diphyllobothriosis in Patagonia, Argentine Novos casos de difilobotriosis humana na região da Patagônia, Argentina

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    Liliana Semenas

    2001-04-01

    Full Text Available The purpose of the paper is to describe 4 new cases of human diphyllobothriosis in Patagonia, Argentine. Adult parasites recovered were submitted to morphological and histological analyses for taxonomic identification. The etiological agent found was always Diphyllobothrium latum and all the cases were autochthonous. These data combined with previous information make the number of autochthonous human cases of diphyllobothriosis registered in Argentina increase to 18.Foram descritos 4 novos casos de difilobotriosis humana na Patagônia, Argentina. Os parasitas adultos foram submetidos a análises morfológicas e histológicas para identificação taxonômica. O agente etiológico foi sempre Diphyllobothrium latum, e todos os casos de difilobotriosis foram autóctones. Esses novos registros se somam aos já previamente detectados, totalizando 18 casos humanos autóctones registrados na Argentina.

  18. Soñar con el futuro. Proyectos inmigratorios para la Patagonia argentina en Teodoro Alemann y Roberto J. Payró

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    Jennifer M. Valko

    2014-06-01

    Taking into account recent studies on journalistic travel and Argentine nation building, this article examines the profile of a type of reporter that has been studied to a lesser degree, the immigrant journalist. It analyzes two travel chronicles about Patagonia published in Buenos Aires in 1898: Ein Ausflug nach dem Chubut-Territorium [An Excursion to the Chubut Territory] by Swiss journalist Theodor Alemann, published in the German-language newspaper Argentinisches Tageblatt [Argentine Daily], and La australia argentina, by Roberto J. Payró which appeared in La Nación. In both chronicles the narration of the trip to Patagonia is interrupted at a key moment by the telling of a dream regarding the future of the region. This essay demonstrates that these oneiric digressions reveal political and economic interests contrary to the official Argentine plans for the development of the region, the role of immigrants and their relationship with European powers.

  19. DIVERSIDAD DE BACTERIAS CULTIVABLES DE LA COSTA DE CALETA OLIVIA, PATAGONIA, ARGENTINA Diversity Of Cultivable Bacteria From The Coast Of Caleta Olivia, Patagonia , Argentina

    Directory of Open Access Journals (Sweden)

    GRACIELA PUCCI

    Full Text Available Caleta Olivia es una ciudad que posee boyas por donde se exporta el petróleo crudo obtenido de la zona norte de la provincia de Santa Cruz, Argentina. Este trabajo tuvo como objetivo estudiar las posibilidades de utilización microbiana de petróleo crudo y sus derivados e identificar las bacterias cultivables que se encuentran presentes en la costa de Caleta Olivia. La mineralización de hidrocarburos se detectó por la producción de dióxido de carbono. Se tomaron muestras de agua de mar y sedimento intermarial de tres sitios. Se realizaron recuentos bacterianos en los medios de cultivo BBR, BRN, medio mineral con petróleo gas oil y ENDO para bacterias coliformes. Las bacterias se identificaron utilizando el sistema de Sherlock de MIDI. Las mineralizaciones evidenciaron la capacidad existente en los microorganismos para la utilización de hidrocarburos. Los recuentos de coliformes fueron negativos. Se aislaron un total de 403 cepas a las que se les realizó la extracción de ácidos grasos e identificación, de ellas solo 172 fueron identificadas por el sistema. Se distribuyeron en 32 géneros y 50 especies bacterianas. El resto, el sistema no las identificó debido a que no halló cepas similares en la base de datos del sistema. Pseudoalteromonas fue el género que más se aisló. El análisis de componentes principales asoció al verano y al otoño con la mayor biodiversidad de géneros. Se encontraron representantes de los siguientes géneros: Arthrobacter, Dietzia, Acinetobacter, Microbacterium, Micrococcus, Bacillus, Pseudomonas y Pseudoalteromonas. Estos microorganismos son citados en la bibliografía como degradadores de hidrocarburos.The aim of this work was to evaluate the oil utilization and identity of the bacterial strains present in the coast Intertidal sediments and marine water from Caleta Olivia city which were analyzed to determine bacterial counts. Five microcosms were designed for sediments and water sample. The

  20. Juego, resistencia y cultura obrera en la Patagonia Argentina: el fútbol ante contextos represivos

    OpenAIRE

    Perez Alvarez, Gonzalo Gabriel

    2015-01-01

    En este artículo rastreamos una de las formas de articulación de la resistencia y organización obrera ante contextos represivos en Argentina. Distintos autores han trabajado la temática de los mecanismos de resistencia obrera durante estas etapas de la historia reciente de Argentina: así se ha observado el trabajo a desgano, los sabotajes, los chistes y bromas contra los jefes, los volantes anónimos, etc. Sin embargo no se ha profundizado acerca de los espacios de encuentro que los ...

  1. A New Species of Ascocotyle (Trematoda: Heterophyidae) from the South American Sea Lion, Otaria flavescens, Off Patagonia, Argentina

    National Research Council Canada - National Science Library

    Jesús Servando Hernández-Orts; Francisco Esteban Montero; Enrique Alberto Crespo; Néstor Aníbal García; Juan Antonio Raga; Francisco Javier Aznar

    2012-01-01

    We describe a new heterophyid species, Ascocotyle (Ascocotyle) patagoniensis n. sp., based on specimens collected from the intestines of the South American sea lion Otaria flavescens from Patagonia...

  2. Monopolizar la violencia en una frontera colonial. Policías y militares en Patagonia austral (Argentina y Chile, 1870-1922)

    OpenAIRE

    Alberto Harambour R.

    2016-01-01

    Este artículo analiza la monopolización de la violencia en el ciclo inicial de colonización de Patagonia austral para lo cual propone, primero, que la precariedad local de los Estados de Argentina y Chile descansó en la fuerza expansiva de la industria ganadera para la instalación de su sobe- ranía territorial; y segundo, que la clausura de la delimitación fronteriza solo se produjo en el verano de 1922, como resultado de la represión a la insurgencia obrera. A partir de una exten...

  3. An assessment of oil pollution in the coastal zone of patagonia, Argentina.

    Science.gov (United States)

    Commendatore, Marta Graciela; Esteves, José Luis

    2007-11-01

    The Patagonian coast is considered a relatively pristine environment. However, studies conducted along coastal Patagonia have showed hydrocarbon pollution mostly concentrated at ports that have fishing, oil loading, general merchant, and/or tourist activities. A high value of total aliphatic hydrocarbons (TAH) was found at the Rawson fishing port (741 microg/g dw). In other ports with and without petroleum-related activities, hydrocarbon values were approximately 100 microg/g dw. The highest values for TAH and total aromatic hydrocarbons (TArH) were found in Faro Aristizábal, north of San Jorge gulf (1304 and 737 microg/g dw, respectively). This is very likely the result of petroleum-related activities at the Comodoro Rivadavia, Caleta Cordova, and Caleta Olivia ports located within this gulf. In other coastal areas away from potential anthropogenic sources, hydrocarbon values were less than 2 and 3 microg/g dw for TAH and TArH, respectively. This review of published and unpublished information suggests that ports are important oil pollution sources in the Patagonian coast. More detailed studies are needed to evaluate the area affected by port activities, to understand the mechanisms of hydrocarbon distribution in surrounding environments, and to assess bioaccumulation in marine organisms. Despite that some regulations exist to control oil pollution derived from port and docked vessel activities, new and stricter management guidelines should be implemented.

  4. Mercury and selenium in the food web of Lake Nahuel Huapi, Patagonia, Argentina.

    Science.gov (United States)

    Arcagni, Marina; Rizzo, Andrea; Juncos, Romina; Pavlin, Majda; Campbell, Linda M; Arribére, María A; Horvat, Milena; Ribeiro Guevara, Sergio

    2017-01-01

    Despite located far from point sources of Hg pollution, high concentrations were recorded in plankton from the deep oligotrophic Lake Nahuel Huapi, located in North Patagonia. Native and introduced top predator fish with differing feeding habits are a valuable economic resource to the region. Hence, Hg and Se trophic interactions and pathways to these fish were assessed in the food web of this lake at three sites, using stable nitrogen and carbon isotopes. As expected based on the high THg in plankton, mercury did not biomagnify in the food web of Lake Nahuel Huapi, as most of the THg in plankton is in the inorganic form. As was observed in other aquatic systems, Se did not biomagnify either. When trophic pathways to top predator fish were analyzed, they showed that THg biomagnified in the food chains of native fish but biodiluted in the food chains of introduced salmonids. A more benthic diet, typical of native fish, resulted in higher [THg] bioaccumulation than a more pelagic or mixed diet, as in the case of introduced fish. Se:THg molar ratios were higher than 1 in all the fish species, indicating that Se might be offering a natural protection against Hg toxicity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Epilithic algae distribution along a chemical gradient in a naturally acidic river, Río Agrio (Patagonia, Argentina).

    Science.gov (United States)

    Baffico, Gustavo D

    2010-04-01

    The epilithic algae distribution along a pH gradient and the relationship between the chemical gradient and biomass development were studied in Río Agrio, a naturally acidic river located in Patagonia (Argentina). The epilithic community was monitored during the summer of three consecutive years in sites located above and below the entrance of tributaries. The epilithic community showed differences between sites based on the chemical composition of the water and the precipitates that appear on the streambed of the river. The lowest biomass, diversity, and number of species were found at the most extreme part of the river in terms of pH (ca. 2) and element concentrations. Euglena mutabilis was the dominant species in this section of the river. As pH increased (ca. 3), the community changed to be dominated by filamentous green algae (Ulothrix spp., Mougeotia sp., Klebsormidium sp.) showing luxuriant growths in terms of biomass. With the inflow of a neutral tributary, the pH of Río Agrio increased above 3, and the precipitates of orange-red iron hydroxides appeared. The algal community was not affected by these precipitates or the low P concentrations, along the next 30 km of river downstream from this site. The apparent physical stress that the precipitates impose on algae is in fact a dynamic reservoir of P because diel cycle of Fe could be promoting precipitation and redissolution processes that binds and releases P from these precipitates. Where the pH increased above 6, precipitates of aluminum hydroxides appeared. At this site, the epilithic biomass and density decreased, some algae species changed, but the diversity and the number of species in general remained consistent with the upstream values. The physical stress of the Al precipitates on the algae is added to the chemical stress that represents the sequestering of P in these precipitates that are not redissolved, resulting P a limiting nutrient for algae growth.

  6. FRAGMENTACIÓN URBANA Y ASOCIACIONES VECINALES EN SAN CARLOS DE BARILOCHE, PATAGONIA - ARGENTINA (1983-2015

    Directory of Open Access Journals (Sweden)

    Brenda Matossian

    2016-01-01

    Full Text Available Las ciudades bajo desarrollo capitalista experimentaron a lo largo de las últimas décadas profundos procesos de fragmentación urbana. Aquellas con función turística agudizaron este panorama dado el aumento del valor del suelo urbano. Tal es el caso de San Carlos de Bariloche, en la Patagonia andina argentina. Su alta compartimentación, sumada a la gran dispersión espacial de su ejido municipal y topografía accidentada, limitaron la funcionalidad y cohesión interna. Se propone avanzar en la comprensión de dichas fracturas urbanas a partir del estudio de las asociaciones vecinales. Se trabaja desde la escala del barrio entendido como condensador de problemáticas globales, nacionales y locales y a partir de la figura de la Junta Vecinal en tanto unidad primaria de participación y principal articuladora en las relaciones entre vecinos, barrios y gobierno local. La hipótesis propone que la gestión, las relaciones y funciones asumidas desde las Juntas Vecinales, íntimamente vinculadas a la condición de clase de sus vecinos, permiten una mejor interacción a escala intraurbana y promueven situaciones más inclusivas en los sectores populares. Se da cuenta también del rol de las Juntas Vecinales en la construcción de imaginarios urbanos que inciden en un acercamiento-alejamiento de las distancias sociales intraurbanas.

  7. Isotopic evidence of weaning in hunter-gatherers from the late holocene in Lake Salitroso, Patagonia, Argentina.

    Science.gov (United States)

    Tessone, Augusto; García Guraieb, Solana; Goñi, Rafael A; Panarello, Héctor O

    2015-09-01

    The timing and duration of breastfeeding and weaning in past hunter-gatherer populations are discussed based on the results of stable carbon and nitrogen isotope analyses undertaken on a Late Holocene skeletal sample from Lake Salitroso in the Patagonian steppe (Argentina). Research in Lake Salitroso is part of a regional project that studies the relationship between hunter-gatherer societies, their organizational systems and the environmental changes during the last 3,000 years in Patagonia. The sample included 52 individuals: 33 subadults and 19 adults of both sexes. They were recovered from 24 burial stone structures, locally called chenques, with dates ranging from ca. 800 BP to 350 BP. Ribs were selected for collagen extraction and measurement of (13) C/(12) C and (15) N/(14) N ratios. A δ(13) C mean value of -18.7‰ ± 0.5‰ was obtained, with a range between -19.8‰ and -17.1‰ whereas δ(15) N recorded a mean of 11.9‰ ± 1.1‰ with a range between 10.1‰ and 14.8‰. δ(15) N data showed an age-related pattern with particularly marked difference between values for subadults under the age of 4 and older individuals. As opposed to δ(15) N, δ(13) C showed little variation with age. An early incorporation of supplementary solid food between 0.75 and 2 years of age and a late cessation of breastfeeding at about 5-6 years of age were inferred. This suggests that among this Patagonian hunter-gatherer population weaning was a gradual and lengthy process. These results are consistent with the patterns observed in cross-cultural studies and archaeological samples of hunter-gatherer groups. © 2015 Wiley Periodicals, Inc.

  8. Validating numerical simulations of snow avalanches using dendrochronology: the Cerro Ventana event in Northern Patagonia, Argentina

    Science.gov (United States)

    Casteller, A.; Christen, M.; Villalba, R.; Martínez, H.; Stöckli, V.; Leiva, J. C.; Bartelt, P.

    2008-05-01

    The damage caused by snow avalanches to property and human lives is underestimated in many regions around the world, especially where this natural hazard remains poorly documented. One such region is the Argentinean Andes, where numerous settlements are threatened almost every winter by large snow avalanches. On 1 September 2002, the largest tragedy in the history of Argentinean mountaineering took place at Cerro Ventana, Northern Patagonia: nine persons were killed and seven others injured by a snow avalanche. In this paper, we combine both numerical modeling and dendrochronological investigations to reconstruct this event. Using information released by local governmental authorities and compiled in the field, the avalanche event was numerically simulated using the avalanche dynamics programs AVAL-1D and RAMMS. Avalanche characteristics, such as extent and date were determined using dendrochronological techniques. Model simulation results were compared with documentary and tree-ring evidences for the 2002 event. Our results show a good agreement between the simulated projection of the avalanche and its reconstructed extent using tree-ring records. Differences between the observed and the simulated avalanche, principally related to the snow height deposition in the run-out zone, are mostly attributed to the low resolution of the digital elevation model used to represent the valley topography. The main contributions of this study are (1) to provide the first calibration of numerical avalanche models for the Patagonian Andes and (2) to highlight the potential of textit{Nothofagus pumilio} tree-ring records to reconstruct past snow-avalanche events in time and space. Future research should focus on testing this combined approach in other forested regions of the Andes.

  9. Validating numerical simulations of snow avalanches using dendrochronology: the Cerro Ventana event in Northern Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    A. Casteller

    2008-05-01

    Full Text Available The damage caused by snow avalanches to property and human lives is underestimated in many regions around the world, especially where this natural hazard remains poorly documented. One such region is the Argentinean Andes, where numerous settlements are threatened almost every winter by large snow avalanches. On 1 September 2002, the largest tragedy in the history of Argentinean mountaineering took place at Cerro Ventana, Northern Patagonia: nine persons were killed and seven others injured by a snow avalanche. In this paper, we combine both numerical modeling and dendrochronological investigations to reconstruct this event. Using information released by local governmental authorities and compiled in the field, the avalanche event was numerically simulated using the avalanche dynamics programs AVAL-1D and RAMMS. Avalanche characteristics, such as extent and date were determined using dendrochronological techniques. Model simulation results were compared with documentary and tree-ring evidences for the 2002 event. Our results show a good agreement between the simulated projection of the avalanche and its reconstructed extent using tree-ring records. Differences between the observed and the simulated avalanche, principally related to the snow height deposition in the run-out zone, are mostly attributed to the low resolution of the digital elevation model used to represent the valley topography. The main contributions of this study are (1 to provide the first calibration of numerical avalanche models for the Patagonian Andes and (2 to highlight the potential of Nothofagus pumilio tree-ring records to reconstruct past snow-avalanche events in time and space. Future research should focus on testing this combined approach in other forested regions of the Andes.

  10. Detrital zircon geochronology and provenance of the Chubut Group in the northeast of Patagonia, Argentina

    Science.gov (United States)

    Navarro, Edgardo L.; Astini, Ricardo A.; Belousova, Elena; Guler, M. Verónica; Gehrels, George

    2015-11-01

    The Chubut Group constitutes the most widespread sedimentary unit in NE Patagonia, characterized by variable-energy fluvial deposits. U-Pb analysis of detrital zircons from two sections of the Chubut Group constraint the age of the oldest sedimentary rocks in the northeast of the Somuncurá - Cañadón Asfalto Basin. In the Cañadón Williams area, at San Jorge section, 20 km NW of Telsen locality, dating of 56 detrital zircons from a medium to coarse sandstone indicated a maximum depositional age of 109 ± 1 Ma (n = 4). These sandstones were interpreted to represent shallow channels, associated with a lacustrine system. In the Telsen locality, a laser ablation analysis of 115 detrital zircons from a medium to coarse-grained sandstone, from fluvial channel facies, yielded a maximum depositional age of ca. 106 ± 1 Ma (n = 8). Both ages are consistent with volcanic events of the Barremian to Albian age in the central Patagonian Andes Region. Cathodoluminescence images of zircons from the San Jorge sample suggest an igneous origin, which is further supported by Th/U values above 0.5 in most of the grains. The distribution of the statistical modes of the main age populations of detrital zircons for the two samples [182, 185 and 189 Ma for Telsen sample (T2S) and 181 ± 1 Ma for San Jorge sample (SJS)] matches the age of the volcanic Marifil Formation. The rocks of the Marifil Formation of these ages are exposed NE to SE of the study area. The abundance of zircons of similar Jurassic ages (n = 52 for SJS and n = 105 for T2S) and the external morphology of the zircons in the sample SJS, implies a close proximity of the source area. Suggestion that the Marifil Formation was the main provenance source is also supported by northeast-southeasterly paleocurrents measured at the San Jorge and Telsen sections.

  11. Assessing pesticide leaching and desorption in soils with different agricultural activities from Argentina (Pampa and Patagonia).

    Science.gov (United States)

    Gonzalez, Mariana; Miglioranza, Karina S B; Aizpún, Julia E; Isla, Federico I; Peña, Aránzazu

    2010-09-01

    Pesticide distribution in the soil profile depends on soil and pesticide properties as well as on the composition of irrigation water. Water containing surfactants, acids or solvents, may alter pesticide desorption from soil. The distribution of organochlorine pesticides (OCPs) in two Argentinean agricultural areas, Pampa and Patagonia, was evaluated. Furthermore, pesticide desorption from aged and freshly spiked soils was performed by the batch technique, using solutions of sodium oxalate and citrate, dissolved organic carbon (DOC), wastewater and surfactants. Patagonian soil showed the highest OCP levels (46.5-38.1 μg g(-1) OC) from 0 to 30 cm depth and the predominance of p,p'-DDE residues reflected an extensive and past use of DDT. Pampean soil with lower levels (0.039-0.07 μg g(-1) OC) was mainly polluted by the currently used insecticide endosulfan. Sodium citrate and oxalate, at levels usually exuded by plant roots, effectively enhanced desorption of p,p'-DDT, p,p'-DDE and α-cypermethrin, while no effects were observed for α-endosulfan and endosulfan sulfate. The non-ionic surfactant Tween 80 behaved similarly to the acids, whereas the anionic sodium dodecyl sulfate enhanced desorption of all pesticides. Increased desorption of the hydrophobic pesticides also occurred when DOC from humic acids but not from sewage sludge or wastewater were used. Soil profile distribution of pesticides was in accordance with results from desorption studies. Data suggest pesticide leaching in Pampean and Patagonian soils, with risk of endosulfan to reach groundwater and that some organic components of wastewaters may enhance the solubilisation and leaching of recalcitrant compounds such as p,p'-DDT and p,p'-DDE. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. New age constraints for the Salamanca Formation and lower Río Chico Group in the western San Jorge Basin, Patagonia, Argentina: Implications for cretaceous-paleogene extinction recovery and land mammal age correlations

    NARCIS (Netherlands)

    Clyde, W.C.; Wilf, P.; Iglesias, A.; Slingerland, R.L.; Barnum, T.; Bijl, P.K.; Bralower, T.J.; Brinkhuis, H.; Comer, E.E.; Huber, B.T.; Ibañez-Mejia, M.; Jicha, B.R.; Krause, J.M.; Schueth, J.D.; Singer, B.S.; Raigemborn, M.S.; Schmitz, M.D.; Sluijs, A.; Zamaloa, M.C.

    2014-01-01

    The Salamanca Formation of the San Jorge Basin (Patagonia, Argentina) preserves critical records of Southern Hemisphere Paleocene biotas, but its age remains poorly resolved, with estimates ranging from Late Cretaceous to middle Paleocene. We report a multi-disciplinary geochronologic study of the

  13. Jurassic hot spring deposits of the Deseado Massif (Patagonia, Argentina): Characteristics and controls on regional distribution

    Science.gov (United States)

    Guido, Diego M.; Campbell, Kathleen A.

    2011-06-01

    The Deseado Massif, Santa Cruz Province, Argentinean Patagonia, hosts numerous Middle to Late Jurassic age geothermal and epithermal features represented by siliceous and calcareous chemical precipitates from hot springs (sinters and travertines, respectively), hydrothermal breccias, quartz veins, and widespread hydrothermal silicification. They indicate pauses in explosive volcanic activity, marking the final stages in the evolution of an extensive Jurassic (ca. 178-151 Ma) volcanic complex set in a diffuse extensional back-arc setting heralding the opening of the Atlantic Ocean. Published paleo-hot spring sites for the Deseado Massif, plus additional sites identified during our recent field studies, reveal a total of 23 locations, five of which were studied in detail to determine their geologic and facies associations. They show structural, lithologic, textural and biotic similarities with Miocene to Recent hot spring systems from the Taupo and Coromandel volcanic zones, New Zealand, as well as with modern examples from Yellowstone National Park, U.S.A. These comparisons aid in the definition of facies assemblages for Deseado Massif deposits - proximal, middle apron and distal siliceous sinter and travertine terraces and mounds, with preservation of many types of stromatolitic fabrics - that likely were controlled by formation temperature, pH, hydrodynamics and fluid compositions. Locally the mapped hot spring deposits largely occur in association with reworked volcaniclastic lacustrine and/or fluvial sediments, silicic to intermediate lava domes, and hydrothermal mineralization, all of which are related to local and regional structural lineaments. Moreover, the numerous geothermal and significant epithermal (those with published minable resources) deposits of the Deseado Massif geological province mostly occur in four regional NNW and WNW hydrothermal-structural belts (Northwestern, Northern, Central, and Southern), defined here by alignment of five or more hot

  14. Petrology of suprasubductive mantle xenoliths from Estancia Sol De Mayo (Central Patagonia, Argentina)

    Science.gov (United States)

    Melchiorre, M.; Coltorti, M.; Gregoire, M.; Benoit, M.

    2012-04-01

    A new suite of mantle xenoliths from Estancia Sol de Mayo (Patagonia) has been investigated. They were entrained in alkaline lavas from the south western sector of Meseta Lago Buenos Aires. Trace element abundances of these lavas are well comparable with those of the main and post-plateau lavas from the Triple Junction Province and resemble those of OIB. Xenoliths are spinel-bearing harzburgites and dunites, with minor lherzolites and one wehrlite. They are characterized by a coarse grained protogranular texture and devoid of modal metasomatic features and hydrated minerals. They show two texturally different clinopyroxenes. One is protogranular (cpx1), while the second surrounds, and is genetically related to, spinel (cpx2). Three different types of orthopyroxenes are also recognized: the first one is represented by large protogranular crystals with exsolution lamellae (opx1), the second one by small clean and undeformed grains without exsolution lamellae (opx2) and the last one occurs as small grains filling veins (opx3). Major element compositions of both clinopyroxenes and orthopyroxenes highlight two different trends. The first one is characterized by high Al2O3 (high-Al trend) content at almost constant mg# [MgO/(MgO+FeO) mol %], while the second shows a slight increase in Al2O3 (low-Al trend) content with decreasing mg#. Trace element contents of cpx are enriched in LREE and characterized by prominent to slightly negative Nb, Zr and Ti anomalies. No differences are observed between cpx1 and cpx2. The three groups of orthopyroxenes are variably depleted in LREE, with opx1 and opx2 always showing prominent to slightly negative Ti and Zr anomalies, while opx3 is characterized by a prominent positive Zr anomaly. Al2O3 in cpx is inversely correlated with LREE and LILE suggesting that a refertilization event occur within the upper mantle beneath Estancia Sol de Mayo. The most likely melt which can account for this event has a tholeiitic affinity, as supported by i

  15. Investigating the deep cool lacustrine biosphere: Lake Potrok Aike, Patagonia, Argentina

    Science.gov (United States)

    Vuillemin, A.; Ariztegui, D.; Pawlowski, J.; Templer, S. P.

    2009-12-01

    Microbial activity on recent sediments is fully recognized as a major player in lithification processes. These omnipresent organisms have the capacity of catalyzing and enhancing diagenetic reactions even in extreme environments from the very surface of the sediments to as deep as 4.5 km below the water column. Living bacterial communities have been tracked down into deep sediments and even into the deeper basaltic sub-seafloors. Although the distribution and diversity of microbes in marine sediments through depth have been studied for some years already, there is a lack of these investigations in the lacustrine realm. Furthermore, geomicrobiology studies in modern lakes allow taking a closer look into early diagenetic processes linked to microbial activity in subrecent sediments. The foci of most of these studies, however, have been either very shallow sediments and/or the water column. More than 500 meters of sedimentary cores were retrieved from Lake Portok Aike, a crater lake located in Southern Patagonia within the framework of the ICDP-sponsored PASADO project (Potrok Aike Maar Lake Sediment Archive Drilling Project). A 100 meters long core was dedicated to geomicrobiology sampling, allowing the inspection of undisturbed deep lacustrine sediments. Special windows were cut in the liners for direct sampling under the most sterile conditions possible immediately after core recovery. In situ ATP measurements are used as indication of living organisms within the sediments. Various samples were chemically fixed and/or frozen for methane determination, bacterial cell counting, DGGE (molecular fingerprinting technique) and cell cultivation. In situ ATP data reveal a constant low microbial activity below 40 m sediment depth whereas three main peaks appear at 37, 10 and 5 meters respectively. Studying the microbial community based on 16S rDNA, we identified a broad, but conserved diversity pattern in the older sediments. In contrast, the diversity seems to decrease and

  16. PRIMERAS INVESTIGACIONES SOBRE UNA ESTRUCTURA MORTUORIA SINGULAR DE CAZADORES-RECOLECTORES EN LA PATAGONIA ARGENTINA: EL ENTIERRO SHAG (The Shag Burial: Preliminary Research Results from a Singular Mortuary Structure of Hunter-Gatherers in Argentinian Patagonia

    Directory of Open Access Journals (Sweden)

    Leandro Zilio

    2017-03-01

    Full Text Available El entierro Shag se ubica en la costa norte de la provincia de Santa Cruz, Patagonia argentina. Se trata de una estructura con morfología anular o de anillo, de aproximadamente 10 m de diámetro, conformada por rocas. La estructura fue alterada por pingüinos de Magallanes, quienes realizaron un pozo de nidificación y, como consecuencia, expusieron en superficie una serie de restos óseos humanos. Para la Patagonia no existen antecedentes de estructuras mortuorias similares a Shag. Se presenta una datación radiocarbónica, el plano de la estructura, determinaciones bioantropológicas, estudios de isótopos estables δ13C y δ15N, y análisis tafonómicos de los restos óseos. Se interpreta que el sitio corresponde a una estructura mortuoria de cazadores-recolectores datada en el Holoceno tardío. Los estudios isotópicos permiten inferir que el individuo analizado basó su dieta en recursos de ambientes marinos y terrestres. ENGLISH: The Shag burial is located in the Santa Cruz province along the northern coast of the Argentinian Patagonia. The Shag burial site is contained by a structure with annular or ring morphology made out of rocks and approximately 10 m in diameter. The structure was altered by Magellanic penguins that built a nesting well, exposing a series of human bone remains on the surface. There is no record of similar mortuary structures within Patagonia. This paper presents a number of data including absolute radiocarbon dates, the plan of the structure, bioanthropological determinations, stable isotope studies of δ13C and δ15N, and taphonomic analyses of the bone remains. The site is interpreted to as a hunter-gatherers mortuary structure dated to the Late Holocene. The isotopic studies on the individual allow us to infer a varied diet, in which both marine and terrestrial food products were consumed.

  17. (129)I dispersion in Argentina: concentrations in fresh and marine water and deposition fluences in Patagonia.

    Science.gov (United States)

    Negri, Agustín E; Fernández Niello, Jorge O; Wallner, Anton; Arazi, Andrés; Fifield, Leslie K; Tims, Stephen G

    2013-09-03

    Measurements of total iodine (I) and iodine-129 ((129)I) concentrations in rivers and lakes of Argentina are presented. Their latitudinal distribution can be explained by taking into account their main sources (oceanic emissions and biomass burning for I, and atmospheric nuclear tests for (129)I), transport mechanisms, and fallout patterns. From the measured (129)I concentrations in the studied lakes, deposition fluences for their catchment areas were estimated. These results agree with a model of the global deposition pattern due to the (129)I released by atmospheric nuclear weapon tests and with other fluences reported for the southern hemisphere. In addition, the first measurements of (129)I in shallow seawater from the South Atlantic Ocean are presented and discussed.

  18. Epidemiological surveillance of ovine hydatidosis in Tierra del Fuego, Patagonia Argentina, 1997-1999.

    Science.gov (United States)

    Zanini, Fabián; Gonzalo, Roberto; Pérez, Héctor; Aparici, Inés; Soto, Ximena; Guerrero, Juvenal; Cerrone, Gloria; Elissondo, Celina

    2006-06-15

    Cystic echinococcosis is the most prevalent zoonosis in Tierra del Fuego province, Argentina, with important economic, productive and public health consequences. The present work was performed to determine the ovine prevalence in Tierra del Fuego, Argentina, as well as to evaluate the quality of diagnostic systems in slaughterhouses. Moreover, genetic analyses to characterize the strain of Echinococcus granulosus involved in the region were done. The first actions to perform a diagnosis of the epidemiological situation of hydatidosis in Tierra del Fuego were done between 1976 and 1977. A canine prevalence of 80% and an ovine prevalence of 55% results were obtained. Since 1979 the control program of Hydatidosis of Tierra del Fuego was implemented. It was based on semiannual canine anthelmintic treatment with praziquantel at dose of 5mg/kg, and complemented with sanitary education and canine and ovine epidemiological surveillance. During May 1997-January 1999: 5,916 sheep coming from 20 farms of the programmatic area were evaluated. In the lamb category, hydatid cysts were not found. In the adults category, 62 infected animals were found (3.2%). The ovine prevalence was 1.1% and there was 100% of coincidence between diagnosis in the slaughterhouse, re-inspection in the laboratory and histopathological study. The marked decrease in the prevalence observed for sheep infection evidenced a destabilization of the biological cycle of the parasite. This could be explained by the application of a control program with uninterrupted systematic actions. Polymerase chain reaction-ribosomal ITS-1 DNA (rDNA) restriction fragment length polymorphism (PCR-RFLP) analysis and partial sequencing of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene were used to characterize E. granulosus isolates collected from different regions of Tierra del Fuego to determine which genotypes occurred in this region. The results revealed the presence of the G1 genotype (sheep-dog strain

  19. Additional information for Leptoglossus impictus (Stål 1859) (Hemiptera: Heteroptera: Coreidae: Coreinae: Anisoscelini) from Patagonia, Argentina.

    Science.gov (United States)

    Diez, Fernando; Espindola, Milton Ruiz; Cornelis, Marcela; Coscarón, María Del Carmen

    2016-01-25

    The Patagonian subregion belongs to the Andean region, and is comprised of two provinces: Central Patagonia and Subandean Patagonia. It extends from central Mendoza, widening through Neuquén, Río Negro, Chubut, and Santa Cruz, to northern Tierra del Fuego, and reaches Chile (Morrone 2006). The knowledge of terrestrial Heteroptera in this region is poor and is limited to a few contributions (e.g. Berg 1979, Breddin 1898, Pennington 1920, Faúndez & Carvajal 2011, Faundez 2015).

  20. Baseline trace metals in bivalve molluscs from the Beagle Channel, Patagonia (Argentina).

    Science.gov (United States)

    Conti, Marcelo Enrique; Stripeikis, Jorge; Finoia, Maria Grazia; Tudino, Mabel Beatriz

    2011-08-01

    In order to test the aptitude of individuals of Mytilus chilensis as biomonitors of heavy metals pollution in seawater, several samples of this mollusk together with surrounding seawater samples were collected along 170 km of the coastal area of the Beagle Channel (Tierra del Fuego, Argentina) in 2005 and 2007. The study, performed in seven locations strategically selected, involved the determination of Cd, Cr, Cu, Ni, Pb and Zn in seawaters and mollusks by atomic absorption spectrometry (AAS) and the calculation of the respective concentration factors (CFs). Obtained data were standardized and analyzed by multivariate techniques in order to establish differences between sampling sites and periods. Obtained results will be shown and the bioaccumulation ability of M. chilensis will be evaluated by comparison with results obtained for Mytilus species in different geographical marine areas. A fully discussion on the possibility of employing the results as background levels for comparative purposes in other marine waters of the world will be provided. The possible harm derived from human consumption of these mollusks will be also assessed.

  1. Baseline trace metals in gastropod mollusks from the Beagle Channel, Tierra del Fuego (Patagonia, Argentina).

    Science.gov (United States)

    Conti, Marcelo Enrique; Stripeikis, Jorge; Finoia, Maria Grazia; Tudino, Mabel Beatriz

    2012-05-01

    With the aim to evaluate the mollusk Nacella (P)magellanica as biomonitor of elemental pollution in seawater of the Beagle Channel, more than one hundred individuals of the gastropod were sampled, separated in viscera and muscle, and then examined with respect to the accumulation of Cd, Cr, Cu, Ni, Pb and Zn. Collection was performed in seven strategic locations along 170 km of the coastal area of the Beagle Channel (Tierra del Fuego, Argentina) in two campaigns during 2005 and 2007. Samples of surrounding seawater in the different sites were obtained and tested for the same metals as well. The accumulation capacity of Nacella (P)magellanica and thus its aptitude as biomonitor, was evaluated through the calculus of the preconcentration factors of the metals assayed. A discussion involving the comparison with other mollusks previously tested will be given. Several statistical approaches able to analyze data with environmental purposes were applied. Non parametric univariate tests such as Kruskal-Wallis and Mann-Whitney were carried out to assess the changes of the metal concentrations with time (2005 and 2007) in each location. Multivariate methods (linear discriminant analysis on PCA factors) were also applied to obtain a more reliable site classification. Johnson's probabilistic method was carried out for comparison between different geographical areas. The possibility of employing these results as heavy metals' background levels of seawater from the Beagle Channel will be debated.

  2. Stone Tool Manufacture Strategies and Lithic Raw Material Exploitation in Coastal Patagonia, Argentina: A Multivariate Approach

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    Marcelo Cardillo

    2013-01-01

    Full Text Available This paper seeks to characterize strategies of artifact manufacture and lithic raw material exploitation along San Matías Gulf coast, Argentina, using multifactorial and cluster analysis. Multifactorial analysis is a relatively new method that has yet to be used for archaeological analysis; it has the advantage that it allows us to describe data using different groups of qualitative or quantitative variables at the same time. Additionally, cluster analysis was conducted on multifactorial axis in a bid to identify grouping patterns. The results obtained from the combination of these two methods suggest that they may be useful in characterizing technological strategies in the study area. Furthermore, they may also be a powerful exploratory and characterization tool able to generate explanations at low spatial scales. The application of these methods on San Matías Gulf study case suggests that along the western and northern coasts of this Gulf the most important variables in determining differences in resource use were the fragmentation ratio and lithic raw materials used in artifact manufacture.

  3. U-Pb zircon constraints on the age of the Cretaceous Mata Amarilla Formation, Southern Patagonia, Argentina: its relationship with the evolution of the Austral Basin Edades U-Pb en circones de la Formación Mata Amarilla (Cretácico, Patagonia Austral, Argentina: su relación con la evoluci��n de la Cuenca Austral

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    Augusto N Varela

    2012-09-01

    Full Text Available Despite the abundant fossil content of the Mata Amarilla Formation (Southern Patagonia, Santa Cruz Province, Argentina, its age has always generated a considerable number of questions and debates. The chronological data provided by invertebrates, dinosaurs, fish, turtles, plesiosaurs and fossil flora are contradictory. In this work, twenty U-Pb spot analyses by laser ablation were carried out on the outer parts of the zoned zircon crystals from a tuff layer of the middle section of the Mata Amarilla Formation, yielding a U-Pb concordia age of 96.23±0.71 Ma, which corresponds to the middle Cenomanian. The deposition of the lower section of the Mata Amarilla Formation marks the onset of the foreland stage of the Austral Basin (also known as Magallanes Basin; this transition is characterized by the west-east shift of the depositional systems, which is consistent with the progradation of the Cretaceous fold-and-thrust belt. Thus, the onset of the foreland stage could have occurred between the upper Albian and lower Cenomanian, as the underlying Piedra Clavada Formation is lower Albian in age. On comparing the data obtained with information from the Última Esperanza Province in Chile, it can be suggested that the initiation of the closure of the Rocas Verdes Marginal Basin occurred simultaneously.A pesar del abundante contenido fosilífero de la Formación Mata Amarilla (Patagonia Austral, Provincia de Santa Cruz, Argentina, siempre se generaron abundantes dudas y debates acerca de cuál es la edad de esta formación. Los datos cronológicos aportados por los invertebrados, los dinosaurios, peces, tortugas, plesiosaurios y flora fósil son dispares. En el presente trabajo se obtuvo una edad U-Pb concordia por la metodología de ablación láser aplicada a 20 puntos de la parte externa de circones zonados provenientes de un nivel tobáceo hallado en la sección media de la Formación Mata Amarilla, lo cual arrojó una edad de 96,23±0,71 Ma, que

  4. Sedimentology and paleoenvironments of the Las Chacritas carbonate paleolake, Cañadón Asfalto Formation (Jurassic), Patagonia, Argentina

    Science.gov (United States)

    Cabaleri, Nora G.; Benavente, Cecilia A.

    2013-02-01

    The Las Chacritas Member is the lower part of the Cañadón Asfalto Formation (Jurassic). The unit is a completely continental limestone succession with volcanic contributions that were deposited during the development of the Cañadón Asfalto Rift Basin (Chubut province, Patagonia, Argentina). A detailed sedimentological analysis was performed in the Fossati depocenter to determine the paleoenvironments that developed in the context of this rift. The Las Chacritas Member represents a carbonate paleolake system with ramp-shaped margins associated with wetlands that were eventually affected by subaerial exposure and pedogenesis. This process is represented by three main subenvironments: a) a lacustrine setting sensu stricto (lacustrine limestone facies association), represented by Mudstones/Wackestones containing porifera spicules (F1), Intraclastic packstones (F6) and Tabular stromatolites (F10) in which deposition and diagenesis were entirely subaqueous; b) a palustrine setting (palustrine limestone facies association) containing Microbial Mudstones (F2), Intraclastic sandy packstone with ostracode remains (F3), Oncolitic packstone (F5), Brecciated limestone (F7) and Nodular-Mottled limestone (F8) representing shallow marginal areas affected by groundwater fluctuations and minor subaerial exposure; and c) a pedogenic paleoenvironment (pedogenic limestone facies association) including Intraclastic limestone (F4) and Packstones containing Microcodium (F9) facies displaying the major features of subaerial exposure, pedogenic diagenesis and the development of paleosols. The fluvial-palustrine-lacustrine succession shows a general shallow upward trend in which contraction-expansion cycles are represented (delimited by exposure and surface erosion). The variations in the successive formations reflect the responses to fluctuations in a combination of two major controls, the tectonic and local climatic variables. The predominance of the palustrine facies associations was

  5. Diverse subaerial and sublacustrine hot spring settings of the Cerro Negro epithermal system (Jurassic, Deseado Massif), Patagonia, Argentina

    Science.gov (United States)

    Guido, Diego M.; Campbell, Kathleen A.

    2012-06-01

    The Late Jurassic (~ 150 Ma) Cerro Negro volcanic-epithermal-geothermal system (~ 15 km2 area), Deseado Massif, Patagonia, Argentina, includes two inferred volcanic emission centers characterized by rhyolitic domes linked along NW-SE regional faults that are associated with deeper level Au/Ag mineralization to the NW, and with shallow epithermal quartz veins and mainly travertine surface hot spring manifestations to the SE. Some travertines are silica-replaced, and siliceous and mixed silica-carbonate geothermal deposits also are found. Five hot spring-related facies associations were mapped in detail, which show morphological and textural similarities to Pleistocene-Recent geothermal deposits at Yellowstone National Park (U.S.A.), the Kenya Rift Valley, and elsewhere. They are interpreted to represent subaerial travertine fissure ridge/mound deposits (low-flow spring discharge) and apron terraces (high-flow spring discharge), as well as mixed silica-carbonate lake margin and shallow lake terrace vent-conduit tubes, stromatolitic mounds, and volcano-shaped cones. The nearly 200 mapped fossil vent-associated deposits at Cerro Negro are on a geographical and numerical scale comparable with subaerial and sublacustrine hydrothermal vents at Mammoth Hot Springs, and affiliated with Yellowstone Lake, respectively. Overall, the Cerro Negro geothermal system yields paleoenvironmentally significant textural details of variable quality, owing to both the differential preservation potential of particular subaerial versus subaqueous facies, as well as to the timing and extent of carbonate diagenesis and silica replacement of some deposits. For example, the western fault associated with the Eureka epithermal quartz vein facilitated early silicification of the travertine deposits in the SE volcanic emission center, thereby preserving high-quality, microbial macro- and micro-textures of this silica-replaced "pseudosinter." Cerro Negro provides an opportunity to reconstruct

  6. A new hadrosauroid (Dinosauria: Ornithopoda from the Allen Formation (Late Cretaceous of Patagonia, Argentina

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    Rubén D. Juárez Valieri

    2010-12-01

    Full Text Available A new hadrosauroid taxon from the Late Cretaceous Allen Formation is erected, on the basis of abundant cranial and postcranial material from the Salitral Moreno locality of the Rio Negro Province, Argentina. The new taxon is here named as Willinakaqe salitralensis gen. et sp. nov., which is characterized by having an autapomorphous premaxilla with a long and convex rostrolateral surface rostral to the narial fossa and associated postcrania developing an unique character combination, including: dorsal vertebrae with a shallow fossa upon the base of the transverse processes; sacral and proximal caudal neural spines more than three times the height of the centrum; distal region of the postacetabular process of ilium ventrally deflected, among others. This new hadrosauroid closely resembles Secernosaurus koerneri, the other valid hadrosauroid species from South America, based in several synapomorphies, as: angle greater than 115° between the lateral margin of the facet for scapular articulation and the glenoid in the coracoid; supra-acetabular process of the ilium asymmetrical, caudodorsal margin of ilium with a well-defined ridge continuous with the dorsal margin of the proximal region of the postacetabular process. Moreover, previous records of Lambeosaurinae from the Late Cretaceous of South America are referred to W. salitralensis, and thus, the presence of lambeosaurines in this continent is here rejected. Accordingly, Willinakaqe salitralensis gen. et sp. nov. is currently the only hadrosauroid species reported from the Allen Formation.Se erige un nuevo taxón de hadrosauroideo del Cretácico Superior de la Formación Allen, en base a abundante material craneal y postcraneal de la localidad de Salitral Moreno, en la Provincia de Río Negro, Argentina. El nuevo taxón es denominado Willinakaqe salitralensis gen. et sp. nov., y se caracteriza por tener un premaxilar autapomórfico con una superficie rostrolateral alargada y convexa rostral a la

  7. Stand dynamics, spatial pattern and site quality in Austrocedrus chilensis forests in Patagonia, Argentina

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    S.L. Burns

    2013-07-01

    Full Text Available Aim of study: The objective of this study was to analyze the stand structure and spatial pattern of two A. chilensis stands with contrasting soil conditions and different site qualities in order to explore if these differences lead to patterns similar to the ones observed under different precipitation conditions.Area of study: The study was carried out in two stands located near the city of El Bolsón (41° 56’S - 71° 33’ W, Rio Negro, Argentina.Material and Methods: We evaluated age difference between canopy strata (upper and lower in two stands with different site qualities by means of a Mann-Whitney test. Dead individuals by diameter class were compared by means of a chi square test. Spatial distribution pattern was analyzed using the pair-correlation function and the mark-correlation function.Main results: Both sites exhibited a random spatial distribution of A. chilensis but different processes seem to underlie the patterns. In the low-quality site facilitation and continuous establishment led to a transient clumped spatial pattern. Mortality mediated by competition occurred mainly on small trees resulting in the current random pattern. On the other hand, spatial pattern in the high-quality site does not reflect a facilitation mediated recruitment. The upper strata established synchronously and subsequent regeneration was episodic.Research highlights: The results show that the differences in site quality may lead to different establishment spatial patterns, showing the importance of facilitation processes in sites with drier soil conditions and lower quality, although results may be site specific, due to the lack of replications.Keywords: Spatial analysis; regeneration; mortality; competition; facilitation.Abbreviations used:  LQ: low-quality site; HQ: high-quality site.

  8. Diversidad de bacterias cultivables de la costa de Caleta Olivia, Patagonia, Argentina

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    pucci graciela natalia

    2009-12-01

    Full Text Available Caleta Olivia es una ciudad que posee boyas de por donde se exporta el petróleo crudo obtenido de la zona norte de la provincia de Santa Cruz –Argentina. Este trabajo tuvo como objetivo estudiar las posibilidades de utilización microbiana de petróleo crudo e identificar las bacterias que se encuentran presentes en la costa. La mineralización de hidrocarburos se siguió por la producción de dióxido de carbono. Se tomaron muestras de agua de mar y sedimento intermarial de tres sitios. Se realizaron recuentos bacterianos en los medios de cultivo BBR, BRN medio mineral con petróleo gas oil y ENDO para bacterias coliformes. Las bacterias se identificaron utilizando el sistema de Sherlock de MIDI. Las mineralizaciones evidenciaron la capacidad existente de los microorganismos para la utilización de hidrocarburos. Los recuentos de coliformes fueron negativos. Se aislaron un total de 403 cepas a las que se les realizó la extracción de ácidos grasos e identificación, de ellas solo 172 fueron identificadas por el sistema. Se distribuyeron en 32 géneros y 50 especies bacterianas. El resto el sistema no las identificó debido a que no halló cepas similares en la base de datos del sistema. Las Pseudoalteromonas fueron el género que más se aisló. El análisis de componentes principales asocio al verano y al otoño con la mayor biodiversidad de géneros. Se encontraron representantes de los siguientes géneros Arthrobacter, Dietzia, Acinetobacter, Microbacterium, Micrococcus, Bacillus, Pseudomonas y Pseudoalteromonas. Estos microorganismos son citados en la bibliografía como degradadores de hidrocarburos.

  9. DIVERSIDAD DE BACTERIAS CULTIVABLES DE LA COSTA DE CALETA OLIVIA, PATAGONIA, ARGENTINA

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    GRACIELA PUCCI

    2009-01-01

    Full Text Available Caleta Olivia es una ciudad que posee boyas por donde se exporta el petróleo crudo obtenido de la zona norte de la provincia de Santa Cruz, Argentina. Este trabajo tuvo como objetivo estudiar las posibilidades de utilización microbiana de petróleo crudo y sus derivados e identificar las bacterias cultivables que se encuentran presentes en la costa de Caleta Olivia. La mineralización de hidrocarburos se detectó por la producción de dióxido de carbono. Se tomaron muestras de agua de mar y sedimento intermarial de tres sitios. Se realizaron recuentos bacterianos en los medios de cultivo BBR, BRN, medio mineral con petróleo gas oil y ENDO para bacterias coliformes. Las bacterias se identificaron utilizando el sistema de Sherlock de MIDI. Las mineralizaciones evidenciaron la capacidad existente en los microorganismos para la utilización de hidrocarburos. Los recuentos de coliformes fueron negativos. Se aislaron un total de 403 cepas a las que se les realizó la extracción de ácidos grasos e identificación, de ellas solo 172 fueron identificadas por el sistema. Se distribuyeron en 32 géneros y 50 especies bacterianas. El resto, el sistema no las identificó debido a que no halló cepas similares en la base de datos del sistema. Pseudoalteromonas fue el género que más se aisló. El análisis de componentes principales asoció al verano y al otoño con la mayor biodiversidad de géneros. Se encontraron repre- sentantes de los siguientes géneros: Arthrobacter, Dietzia, Acinetobacter, Microbacterium, Micrococcus, Bacillus, Pseudomonas y Pseudoalteromonas. Estos microorganismos son citados en la bibliografía como degradadores de hidrocarburos.

  10. Distribución geográfica, historia natural y conservación del hurón menor Galictis cuja (Carnivora: Mustelidae en la Patagonia central, Argentina Geographic distribution, natural history and conservation of the lesser grison Galictis cuja (Carnivora: Mustelidae from Central Patagonia, Argentina

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    Marcelo Carrera

    2012-12-01

    Full Text Available El hurón menor, Galictis cuja, tiene una amplia distribución en el territorio patagónico extraandino, aunque sus registros puntuales son escasos. Este trabajo se desarrolló en la provincia del Chubut, Patagonia Central, Argentina. Aquí se aportan nuevas localidades de registro de G. cuja para esta región; se discuten aspectos de su distribución geográfica y conservación en el Área Natural Protegida Península Valdés (ANP-PV; Patrimonio Natural de la Humanidad y brevemente se explora la representación de G. cuja en los ensambles de carnívoros del ANP-PV desde el Holoceno tardío hasta la actualidad. Se adicionaron 18 nuevos registros de G. cuja en Patagonia central. Se detectó un conflicto entre los pobladores y hurones, que motiva la caza de estos últimos. Se verificó un aparente incremento de abundancia de G. cuja en los últimos miles de años, concomitante con la extinción regional o dramática disminución de Lyncodon patagonicus (Carnivora, Mustelidae.The Lesser Grison, Galictis cuja, is a species widely distributed in extra-Andean Patagonia, although its records are scarce. This work was carried out in Chubut province, Central Patagonia, Argentina. Here we report new occurrence localities of G. cuja for this region; we discuss aspects of their geographical distribution and conservation in the Área Natural Protegida Península Valdés (ANP-PV; World Heritage Site and briefly explores the representation of G. cuja in carnivore assemblages of ANP-PV, since the late Holocene to the present. We added 18 new records of G. cuja in Central Patagonia. We detected a conflict between the rural residents and the Lesser Grison, which motivates the hunting of the latter. There was an apparent increase in abundance of G. cuja in the last thousands of years, concomitant with regional extinction or dramatic reduction of Lyncodon patagonicus (Carnivora, Mustelidae.

  11. Patrimonio arqueológico, memoria y territorio. Procesos de autoctonización entre los mapuches de Lago Puelo, Chubut (Patagonia, Argentina

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    Carolina Crespo

    2011-01-01

    Full Text Available Este artículo analiza las disputas de sentido que se configuran en torno de la categoría de "autoctonía" en la localidad de Lago Puelo -Comarca Andina del Paralelo 42º, noroeste de Chubut, Patagonia, Argentina-, su articulación con determinados derechos y demandas de la población mapuche y el lugar que ocupa el patrimonio arqueológico en el proceso de autoctonización de esta población dentro de procesos hegemónicos cambiantes. Tal forma de categorización resulta central en las modalidades de construcción de identidades políticas de los pueblos indígenas, de configuración de sus demandas y de las políticas estatales de reconocimiento de derechos hacia estos pueblos.

  12. First fossil record of Discocephalinae (Insecta, Pentatomidae): a new genus from the middle Eocene of Río Pichileufú, Patagonia, Argentina

    Science.gov (United States)

    Petrulevičius, Julián F.; Popov, Yuri A.

    2014-01-01

    Abstract A new genus and species of Discocephalini, Acanthocephalonotum martinsnetoi gen. n. et sp. n. is described from Río Pichileufú, middle Eocene of Patagonia, Argentina at palaeolatitude ~ 46°S. The new species is the first fossil representative of the Discocephalinae. This taxon is extant in equatorial to subtropical America, and some species reach warm temperate latitudes (Buenos Aires province). The new genus is distinguished from the other genera of Discocephalini by the combination of these characters: interocular width greater than head length; head massive and quadrangular with the anterior margin almost straight; juga touching each other; labrum thick and curved; triangular ante-ocular process extending beyond the eye; broad spine-like antero-lateral process of the pronotum; pronotum explanate and bean shaped; scutellum triangular with a circular tongue reaching the anterior side of abdominal segment 7; and wings well developed with membrane just surpassing end of abdomen. PMID:25061387

  13. Sweet cherries from the end of the world: options and constraints for fruit production systems in South Patagonia, Argentina

    NARCIS (Netherlands)

    Cittadini, E.D.

    2007-01-01

    In South Patagonia, development of the fruit production sector has been almost exclusively based on the production of sweet cherry, with an area increase from 176 ha in 1997 to 578 ha at the end of 2006. These orchards are designed as intensive systems and oriented to export markets. Even though

  14. Using dental enamel wrinkling to define sauropod tooth morphotypes from the Cañadón Asfalto Formation, Patagonia, Argentina.

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    Femke M Holwerda

    Full Text Available The early Middle Jurassic is regarded as the period when sauropods diversified and became major components of the terrestrial ecosystems. Not many sites yield sauropod material of this time; however, both cranial and postcranial material of eusauropods have been found in the Cañadón Asfalto Formation (latest Early Jurassic-early Middle Jurassic in Central Patagonia (Argentina, which may help to shed light on the early evolution of eusauropods. These eusauropod remains include teeth associated with cranial and mandibular material as well as isolated teeth found at different localities. In this study, an assemblage of sauropod teeth from the Cañadón Asfalto Formation found in four different localities in the area of Cerro Condor (Chubut, Argentina is used as a mean of assessing sauropod species diversity at these sites. By using dental enamel wrinkling, primarily based on the shape and orientation of grooves and crests of this wrinkling, we define and describe three different morphotypes. With the exception of one taxon, for which no cranial material is currently known, these morphotypes match the local eusauropod diversity as assessed based on postcranial material. Morphotype I is tentatively assigned to Patagosaurus, whereas morphotypes II and III correspond to new taxa, which are also distinguished by associated postcranial material. This study thus shows that enamel wrinkling can be used as a tool in assessing sauropod diversity.

  15. Using dental enamel wrinkling to define sauropod tooth morphotypes from the Cañadón Asfalto Formation, Patagonia, Argentina.

    Science.gov (United States)

    Holwerda, Femke M; Pol, Diego; Rauhut, Oliver W M

    2015-01-01

    The early Middle Jurassic is regarded as the period when sauropods diversified and became major components of the terrestrial ecosystems. Not many sites yield sauropod material of this time; however, both cranial and postcranial material of eusauropods have been found in the Cañadón Asfalto Formation (latest Early Jurassic-early Middle Jurassic) in Central Patagonia (Argentina), which may help to shed light on the early evolution of eusauropods. These eusauropod remains include teeth associated with cranial and mandibular material as well as isolated teeth found at different localities. In this study, an assemblage of sauropod teeth from the Cañadón Asfalto Formation found in four different localities in the area of Cerro Condor (Chubut, Argentina) is used as a mean of assessing sauropod species diversity at these sites. By using dental enamel wrinkling, primarily based on the shape and orientation of grooves and crests of this wrinkling, we define and describe three different morphotypes. With the exception of one taxon, for which no cranial material is currently known, these morphotypes match the local eusauropod diversity as assessed based on postcranial material. Morphotype I is tentatively assigned to Patagosaurus, whereas morphotypes II and III correspond to new taxa, which are also distinguished by associated postcranial material. This study thus shows that enamel wrinkling can be used as a tool in assessing sauropod diversity.

  16. Calliphoridae (Diptera from Southeastern Argentinean Patagonia: Species Composition and Abundance Calliphoridae (Diptera del Sudeste de la Patagonia Argentina: Composición Específica y Abundancia

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    Juan A. Schnack

    2004-07-01

    Full Text Available Species composition and spatial and temporal numerical trends of blow flies (Diptera, Calliphoridae species from three southeastern Patagonia localities: Río Grande (53° 48' S, 67° 36' W (province of Tierra del Fuego, Río Gallegos (51° 34' S, 69° 14' W and Puerto Santa Cruz (50° 04' S, 68° 27' W (province de Santa Cruz were studied during November, December (1997, and January and February (1998. Results showed remarkable differences of overall fly abundance and species relative importance at every sampling site; nevertheless, they shared a poor species representation (S £ 6. The cosmopolitan Calliphora vicina Robineau-Desvoidy, the nearly worldwide Lucilia sericata (Meigen, and the native Compsomyiops fulvicrura (Robineau-Desvoidy prevailed over the remaining species. Records of Protophormia terraenovae (Robineau-Desvoidy, a species indigenous to the Northern Hemisphere are noteworthy.Se estudian la composición y las variaciones numéricas espacio-temporales de especies de Calliphoridae (Diptera de tres localidades del sudeste patagónico: Río Grande (53° 48' S, 67° 36' W (provincia de Tierra del Fuego, Río Gallegos (51° 34' S, 69° 14' W y Puerto Santa Cruz (50° 04' S, 68° 27' W (provincia de Santa Cruz, a partir de muestreos realizados en noviembre, diciembre (1997, enero y febrero (1998. Comparando los sitios de muestreo, los resultados obtenidos muestran diferencias marcadas en la abundancia total de la taxocenosis como de cada una de sus especies, destacándose la escasa riqueza específica de cada uno de ellos (S £ 6. Calliphora vicina Robineau-Desvoidy (cosmopolita, Lucilia sericata (Meigen (de amplia distribución mundial y Compsomyiops fulvicrura (Robineau-Desvoidy (nativa, son las mejor representadas numéricamente. Se subraya el hallazgo, en el área de estudio, de Protophormia terraenovae (Robineau-Desvoidy, especie indígena del hemisferio norte.

  17. Geomorphology context and characterization of dunefields developed by the southern westerlies at drying Colhué Huapi shallow lake, Patagonia Argentina

    Science.gov (United States)

    Montes, Alejandro; Rodríguez, Silvana Soledad; Domínguez, Carlos Eduardo

    2017-10-01

    Patagonia is the only continental territory exposed to the southern westerlies. The speed and frequency of these westerly winds generate a landscape strongly influenced by aeolian processes. This research shows a characterization of depositional and erosive aeolian landforms developed in dunefields associated to Lake Colhué Huapi, in the Extra-Andean Patagonia. Dunefields are located at 45°-46°S and moved in west-east direction due to the southern westerlies. We identified two big groups of active dunefields, one migrating through the dry lakebed of Colhué Huapi and the other migrating eastwards from the lakeshore. The dunefields mainly consist of transverse dunes, barchans, sand shadows and sand sheets. Yardangs, desert pavements, exhumed roots and decapitated soils were recognized in interdune areas. Longitudinal sand ridges, parallel to the prevailing wind direction, often remain preserved after the dunefields have passed. This allows to recognize the path of the dunes in the past. Sand ridges are recognized up to 28 km east from the present coast of the lake and evidenced former dunefields development. We describe the geomorphology context, landforms and sediments supply of dunefields related to the lake dynamics subject to clear tendency to desiccation.

  18. Aporocotyle mariachristinae n. sp., and A. ymakara Villalba & Fernández, 1986 (Digenea: Aporocotylidae) of the pink cusk-eel, Genypterus blacodes (Ophidiiformes: Ophidiidae) from Patagonia, Argentina

    Science.gov (United States)

    Hernández-Orts, J.S.; Alama-Bermejo, G.; Carrillo, J.M.; García, N.A.; Crespo, E.A.; Raga, J.A.; Montero, F.E.

    2012-01-01

    Aporocotyle mariachristinae n. sp. and A. ymakara Villalba & Fernández, 1986 were collected from the bulbus arteriosus and ventral aorta of pink cusk-eels, Genypterus blacodes (Forster, 1801) from Patagonia, Argentina. A. mariachristinae n. sp. can be distinguished from all the species of Aporocotyle by the asymmetrical extension of posterior caeca (right posterior caecum longer, terminating at the area between mid-level of ovary and posterior body end; left posterior caecum shorter, terminating at the area between mid-level of cirrus sac and posterior to reproductive organs), the distribution of spines along the ventro-lateral body margins and the number of testes. The new species clearly differs from A. ymakara, from the same host species, in the esophagus / body length ratio, the absence of distal loops at caeca, the anterior caeca / posterior caeca length ratio, and the number of testes. Additionally, in A. ymakara the left posterior caecum may be longer than right posterior caecum, while in the new species left posterior caecum is always shorter. The specimen of A. ymakara collected from Argentina is also described. We also provide observations of the distribution of spines in different species of Aporocotyle, including new specimens of A. argentinensis Smith, 1969 from Merluccius hubbsi Marini, 1933. Molecular sequence data obtained from partial 18S and 28S rDNA regions were compared between the new species and other two species of Aporocotyle (A. argentinensis and A. spinosicanalis Williams, 1958). This is a new locality record for A. ymakara, extending the known geographical distribution for this species from Chile to Argentina, and the first report of two species of Aporocotyle in the same host species and locality. PMID:23193516

  19. ESTIMACIÓN DE EROSIÓN HIDRICA DE SUELOS PARA PLAN DE MANEJO DEL CAMPO FORESTAL AGUAS FRÍAS, PATAGONIA ARGENTINA

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    Ana C. Dufilho

    2011-12-01

    Full Text Available In Argentine Patagonia there exist large extensions of lands degraded by overgrazing, this favours soil water erosion. Two million hectares are eligible for forestation (Gallo et al. 2005, with some environmental limitations that require previous studies to prepare development and sustainability proposals. The study area is located in the right margin of the Litrán River, 25 kms of its estuary in Aluminé Lake (Province of Neuquén. In this area, some Mapuche (araucanian communities carry out stock breeding (mainly goats using a migrating system. This region presents very severe Aeolian and hydrological erosion. The objective of the afforestation management plan of this land, is the design of control measures, to stop erosion, like perimeter close, afforestation and structural measures for controlling erosional gully. It is then necessary, to characterize the actual and potential erosion, that would allow to carry out with measures monitoring to implement controls and mitigation. Paper presents, pedology map by interpreting and georreferencing satellite images by a Geographical Information System. (GIS. The mapping methodology was based in Hierarchical Classification of Landforms, which is the structure of the geopedology focus for mapping soil (Zinck, 1989. The classification of actual erosion was obtained from the method of the Bureau of Land Management (USDI by visual inspection of seven aspects of erosion in surface. The estimation of the potential erosion of the floors of the forest field was carried out utilizing the Universal Soil Lost Equation (USLE and ArcGis 9,2 (ESRI, 2006 to carry out the spatial analysis, obtaining a map of annual soil loss ( tn/has/year with a spatial resolution of 30 m. The application of spatial analysis tools in the study of soil water erosion in Patagonia, Argentina contributes to the objective of defining define a program of development and adequate management, as a function of the state and degree of

  20. Argentina.

    Science.gov (United States)

    1986-06-01

    This discussion of Argentina covers geography, the people, history and political conditions, government, economy, foreign relations, and relations between the US and Argentina. In 1985, the population of Argentina was estimated to be 30.6 million with an estimated annual growth rate of 1.5%. The infant mortality rate is 34.1/1000, and life expectancy is 70.2 years. Argentina, which shares land borders with Bolivia, Brazil, Chile, Paraguay, and Uruguay, is bounded by the Atlantic and the Antarctic Oceans. Descendants of Italian and Spanish immigrants predominate in Argentina, but many trace their origins to British and West and East European ancestors. In recent years, there has been a substantial influx of immigrants from neighboring Latin American countries. The native Indian population, estimated to be 50,000, is concentrated in the peripheral provinces of the north, northwest, and south. What is now Argentina was discovered in 1516 by the Spanish navigator Juan de Solia. The formal declaration of independence from Spain was made on July 9, 1816. In the late 19th century, 2 forces worked to create the modern Argentine nation: the introduction of modern agricultural techniques and the integration of Argentina into the world economy. Argentina has impressive human and natural resources, but political conflict and uneven economic performance since World War II have impeded full realization of its considerable potential. Yet, it is one of the wealthiest countries in Latin America. Among the reasons for the military coup of March 1976 was the deteriorating economy, caused by declining production and rampant inflation. Under the leadership of the Minister of the Economy, the military government focused attention on those immediate problems, and, in 1978, embarked on a new development strategy focusing on the establishment of a free market economy. There was little improvement in the economy, and a new economic plan was introduced in 1985 which has capped inflation by

  1. Formación ética y ciudadana. Vicisitudes de la transformación curricular en la Patagonia Argentina

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    Isabelino A Siede

    2015-01-01

    Full Text Available ¿Qué tipo de educación ética y ciudadana ofrecen efectivamente las escuelas? En este artículo se analizan las prescripciones curriculares de formación ética y ciudadana en las escuelas de educación básica de la Patagonia argentina, y sus relaciones y contradicciones con las prácticas escolares de educación moral. Se indaga el proceso de definición del área en el contexto de la reforma educativa de los años noventa y busca reconstruir su modalidad de incorporación en el diseño curricular provincial de Santa Cruz, como expresión de las intenciones explícitas e implícitas de esa política curricular. A través de grupos focales y entrevistas a docentes de diferentes escuelas públicas y privadas de tres localidades del norte santacruceño, se analizan las descripciones, valoraciones y expectativas de los docentes sobre sus prácticas de enseñanza en el terreno moral, así como también las posibles causas de las distancias y contradicciones entre las políticas de enunciación curricular y las propuestas formativas que ofrecen las escuelas.

  2. A Large Accumulation of Avian Eggs from the Late Cretaceous of Patagonia (Argentina) Reveals a Novel Nesting Strategy in Mesozoic Birds

    Science.gov (United States)

    Fernández, Mariela S.; García, Rodolfo A.; Fiorelli, Lucas; Scolaro, Alejandro; Salvador, Rodrigo B.; Cotaro, Carlos N.; Kaiser, Gary W.; Dyke, Gareth J.

    2013-01-01

    We report the first evidence for a nesting colony of Mesozoic birds on Gondwana: a fossil accumulation in Late Cretaceous rocks mapped and collected from within the campus of the National University of Comahue, Neuquén City, Patagonia (Argentina). Here, Cretaceous ornithothoracine birds, almost certainly Enanthiornithes, nested in an arid, shallow basinal environment among sand dunes close to an ephemeral water-course. We mapped and collected 65 complete, near-complete, and broken eggs across an area of more than 55 m2. These eggs were laid either singly, or occasionally in pairs, onto a sandy substrate. All eggs were found apparently in, or close to, their original nest site; they all occur within the same bedding plane and may represent the product of a single nesting season or a short series of nesting attempts. Although there is no evidence for nesting structures, all but one of the Comahue eggs were half-buried upright in the sand with their pointed end downwards, a position that would have exposed the pole containing the air cell and precluded egg turning. This egg position is not seen in living birds, with the exception of the basal galliform megapodes who place their eggs within mounds of vegetation or burrows. This accumulation reveals a novel nesting behaviour in Mesozoic Aves that was perhaps shared with the non-avian and phylogenetically more basal troodontid theropods. PMID:23613776

  3. Detection of Leishmania DNA in wild foxes and associated ticks in Patagonia, Argentina, 2000 km south of its known distribution area.

    Science.gov (United States)

    Millán, Javier; Travaini, Alejandro; Zanet, Stefania; López-Bao, José Vicente; Trisciuoglio, Anna; Ferroglio, Ezio; Rodríguez, Alejandro

    2016-04-28

    Zoonotic Visceral Leishmaniasis (ZVL) is a vector-borne disease affecting humans and other mammals and caused by the protozoan parasite Leishmania (Leishmania) infantum (syn. L. chagasi), belonging to the L. donovani complex. The regions in Northern Argentina (above 32 °S) are its southern distribution limit in South America. We detected Leishmania sp. DNA (most likely belonging to the L. donovani complex) in 37.5% of 32 grey foxes (Pseudalopex griseus) captured in Argentinean Patagonia (48°S and 50°S). Eleven monosexual pools of Amblyomma tigrinum ticks from eight different foxes (six grey foxes and two culpeo foxes P. culpaeus) were also positive. The southernmost known distribution limit for L. infantum, and the southernmost reported capture of a phlebotominae, had previously been 2000 and 750 km north of our study area, respectively. This finding is significant because it markedly extends the distribution area of leishmaniasis; supports the existence of a sylvatic cycle in the absence of dogs; and has implications in transmission, indicating that either sand fly distribution is broader than currently thought or non-sand fly Leishmania maintenance is possible. Additional molecular, parasitological, epidemiological and entomological studies are still needed.

  4. LAS NORMAS JURÍDICAS Y LAS POLÍTICAS PÚBLICAS SOBRE BOSQUES CULTIVADOS EN LAS REGIONES DEL CENTRO Y DE PATAGONIA EN ARGENTINA

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    C. M. MINAVERRY

    2017-08-01

    Full Text Available El eje central de este trabajo es analizar el nivel de desarrollo de las normas jurídicas, de las políticas públicas, y de la idoneidad de las autoridades de aplicación sobre bosques cultivados, en las regiones del Centro y de la Patagonia en Argentina. Se trata de una investigación de carácter exploratorio, donde se aplicó el método de la hermenéutica jurídica y los indicadores ambientales PER. Se puede concluir que los niveles de desarrollo normativo de las provincias no son uniformes, y que la mayoría de las normas jurídicas y de las políticas públicas tienden a establecer incentivos económicos para aprovechar el efecto del mercado, sin orientarse hacia una protección integral de los ecosistemas boscosos, y que las autoridades de aplicación en su mayoría no son técnicamente adecuadas para eso.

  5. Modern and subrecent spatial distribution and characteristics of sediment infill controlled by internal depositional dynamics, Laguna Potrok Aike (southern Patagonia, Argentina)

    Science.gov (United States)

    Kastner, S.; Ohlendorf, C.; Haberzettl, T.; Lücke, A.; Maidana, N. I.; Mayr, C.; Schäbitz, F.; Zolitschka, B.

    2009-04-01

    . Nonetheless, these homogenous patterns indicate distinct variations over time as several tributaries and the north-eastern outflow become influencing variables of the sediment distribution. Acknowledgements We are much obliged to Eva Hering (University of Cologne) for providing pollen data of her diploma thesis and to Thomas Chwalek (University of Munich) for providing isotope data of his bachelor thesis. References Haberzettl, T. et al. (2005). Climatically induced lake level changes during the last two millennia as reflected in sediments of Laguna Potrok Aike, southern Patagonia (Santa Cruz, Argentina). Journal of Paleolimnology 33: 283-302. Haberzettl, T. et al. (2007). Lateglacial and Holocene wet-dry cycles in southern Patagonia: chronology, sedimentology and geochemistry of a lacustrine record from Laguna Potrok Aike, Argentina. The Holocene, 17: 297-310. Mayr, C. et al. (2009). Isotopic and geochemical fingerprints of environmental changes during the last 16,000 years on lacustrine organic matter from Laguna Potrok Aike (southern Patagonia, Argentina). Journal of Paleolimnology. doi: 10.1007/s10933-008-9249-8). Wille, M. et al. (2007). Vegetation and climate dynamics in southern South America: The microfossil record of Laguna Potrok Aike, Santa Cruz, Argentina. Review of Palaeobotany and Palynology 146: 234-246.

  6. Monopolizar la violencia en una frontera colonial. Policías y militares en Patagonia austral (Argentina y Chile, 1870-1922

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    Alberto Harambour R.

    2016-01-01

    Full Text Available Este artículo analiza la monopolización de la violencia en el ciclo inicial de colonización de Patagonia austral para lo cual propone, primero, que la precariedad local de los Estados de Argentina y Chile descansó en la fuerza expansiva de la industria ganadera para la instalación de su sobe- ranía territorial; y segundo, que la clausura de la delimitación fronteriza solo se produjo en el verano de 1922, como resultado de la represión a la insurgencia obrera. A partir de una extensa investigación en fuentes oficiales y empresariales referidas a Santa Cruz, Magallanes y Tierra del Fuego, así como en la prensa local, se investiga y compara la presencia de la fuerza policial y militar en las subdivisiones administrativas del extremo sur; además se examinaron similitudes y diferencias en las estra- tegias de control social.

  7. New azhdarchoid pterosaur (Pterosauria, Pterodactyloidea with an unusual lower jaw from the Portezuelo Formation (Upper Cretaceous, Neuquén Group, Patagonia, Argentina

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    ALEXANDER W.A. KELLNER

    2017-09-01

    Full Text Available ABSTRACT A new azhdarchoid pterosaur from the Upper Cretaceous of Patagonia is described. The material consists of an incomplete edentulous lower jaw that was collected from the upper portion of the Portezuelo Formation (Turonian-Early Coniacian at the Futalognko site, northwest of Neuquén city, Argentina. The overall morphology of Argentinadraco barrealensis gen. et sp. nov. indicates that it belongs to the Azhdarchoidea and probable represents an azhdarchid species. The occlusal surface of the anterior portion is laterally compressed and shows blunt lateral margins with a medial sulcus that are followed by two well-developed mandibular ridges, which in turn are bordered laterally by a sulcus. The posterior end of the symphysis is deeper than in any other azhdarchoid. This unique construction of the lower jaw suggests the existence of an elaborate interlocking mechanism with the upper jaw. Furthermore, although speculative, it is advocated here that Argentinadraco barrealensis might have used the lower jaw to obtain its prey by cutting or ploughing through unconsolidated sediment in shallow waters, a feeding behavior not previously proposed for pterosaurs.

  8. Effects of Post-Fire Plant Cover in the Performance of Two Cordilleran Cypress ( Austrocedrus chilensis) Seedling Stocktypes Planted in Burned Forests of Northeastern Patagonia, Argentina

    Science.gov (United States)

    Urretavizcaya, María F.; Gonda, Héctor E.; Defossé, Guillermo E.

    2017-03-01

    Cordilleran cypress ( Austrocedrus chilensis [D.Don] Pic. Serm. et Bizarri) forests occupy 140,000 ha along a sharp environmental gradient of central Andean-Patagonia in Argentina. Every summer, about 3200 ha of these forests are affected by wildfires, taking thereafter long time to recover. To accelerate forest recovery, we determined in xeric and mesic cypress stands burned 5 and 2 year before whether survival and growth of two planted cypress seedling stocktypes are affected by plant cover and contrasting precipitation conditions. Two experiments were conducted on each site, involving 100 replicates of two seedling stocktypes, having each significantly different morphological attributes. The experiments comprised a dry and humid growing season on each site. Both stocktypes performed similarly within stands, but differently between stands. In the xeric stand, plant cover had neutral effects on seedling survival, favored seedling height growth in the dry season, and was negative on collar diameter and stem growth. In the mesic site, high plant cover favored survival and height growth, but was inconsequential for collar diameter and stem growth. In this short-term post-fire period, and independent of precipitation received during both seasons (dry or humid), plant cover appears as playing a facilitative role, having neutral or even positive effects on survival and growth of planted seedlings. During the early post-fire successional stages, and besides seedling stocktype, there was a synergistic balance between light and soil moisture that seems to benefit planted seedling performance in burned cypress forests, and especially in mesic sites.

  9. EXPLOTACIÓN DE ESPECIES VEGETALES EN LA PATAGONIA SEPTENTRIONAL: EL REGISTRO ARQUEOBOTÁNICO DE CUEVA HUENUL 1 (PROVINCIA DE NEUQUÉN, ARGENTINA

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    Carina Llano

    2013-01-01

    Full Text Available Se presenta el análisis de los restos vegetales provenientes del sitio Cueva Huenul 1, Provincia de Neuquén, Argentina, el cual aporta nuevos conocimientos sobre el proceso de poblamiento, la explotación del medio ambiente y el uso de los recursos vegetales. La secuencia cronológica del sitio abarca desde la transición Pleistoceno-Holoceno hasta tiempos recientes. Los restos arqueológicos podrían haber sido depositados por sociedades cazadoras-recolectoras. Los taxones recuperados corresponden a especies silvestres autóctonas, las cuales concuerdan con el paisaje regional, y a un taxón domesticado (Lagenaria sp.. Se aborda el análisis tafonómico a fin de evaluar la incidencia antrópica o natural en la formación del conjunto arqueobotánico estudiado. Finalmente, se integran estos resultados con los datos proporcionados por otros indicadores arqueológicos y paleoecológicos, permitiendo una primera caracterización de la subsistencia humana en la escala del sitio. La ampliación espacial de este análisis permitirá evaluar la variación en la subsistencia en diferentes ambientes del noroeste de Patagonia.

  10. Productive and income contributions of sheep, goat, and cattle, and different diversification schemes in smallholder production systems of Northern Patagonia, Argentina.

    Science.gov (United States)

    Villagra, Edgar Sebastián; Easdale, Marcos Horacio; Giraudo, Celso Gabriel; Bonvissuto, Griselda Luz

    2015-10-01

    Wool production oriented sheep keeping is the most important rural activity in Patagonia, Argentina, followed by goat and at a lower extent cattle production. The existing perception on the smallholder production systems from most decision makers (e.g., policy) is that they are marginal, with low productivity and have negative returns. Since the Argentinean economic scenario has changed drastically in the last decade, the aim of this study was to analyze the economic and productive contribution of different livestock species in smallholdings. The results showed that the post-1990's economic scenario turned most smallholder livestock systems to have positive economic performance, but there were still productive restrictions that limited to fully benefit from these favorable circumstances. Goats were the most profitable livestock due to their higher productive performance, followed by sheep and cattle, with poorer performances. A strong cooperation between the intervention programs and research institutions is recommended to overcome the current production bottlenecks, by focusing on cattle and sheep production systems.

  11. Territorio y ganadería en la Patagonia Argentina: desertificación y rentabilidad en la Meseta Central de Santa Cruz

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    Larry Andrade

    2002-01-01

    Full Text Available El artículo revisa brevemente las características que asume el proceso de desertificación en la Patagonia Austral, con énfasis en la provincia de Santa Cruz, Argentina. Se hacen referencias a la ocupación del territorio santacruceño por el ganado ovino, a fines del siglo XIX y con más intensidad a principios del siglo XX, y el impacto que ello conllevó, especialmente el desencadenamiento de un proceso erosivo (desertificación, producido básicamente por el pastoreo constante (sobrepastoreo del pastizal natural. También se encuentran referencias al sector ganadero y su participación en el producto bruto geográfico (PBG de Santa Cruz y, hacia el final, un análisis comparativo de la cantidad de animales que el productor estima que puede sostener en su campo y la cantidad que el Instituto Nacional de Tecnología Agropecuaria (INTA, con base en relevamientos de pastizal, calcula que podría mantener.

  12. Study of cloud enhanced surface UV radiation at the atmospheric observatory of Southern Patagonia, Río Gallegos, Argentina

    Science.gov (United States)

    Wolfram, Elian A.; Salvador, Jacobo; Orte, Facundo; Bulnes, Daniela; D'Elia, Raul; Antón, Manuel; Alados-Arboledas, Lucas; Quel, Eduardo

    2013-05-01

    Ozone and ultraviolet (UV) radiation are two important issues in the study of Earth's atmosphere. The anthropogenic perturbation of the ozone layer has induced change in the amount of UV radiation that reaches the Earth's surface, mainly through the Antarctic ozone hole. Also clouds have been identified as the main modulator of UV amount over short time scales. While clouds can decrease direct radiation, they can produce an increase in the diffuse component, and as a consequence the surface UV radiation may be higher than during an equivalent clear sky scenario. In particular this situation can be important when a low ozone column and partially cloud coverered skies occur simultaneously. These situations happen frequently in southern Patagonia, where the CEILAP Lidar Division has established the Atmospheric Observatory of Southern Patagonia, an atmospheric remote sensing site near the city of Río Gallegos (51°55'S, 69°14'W). In this paper, the impact of clouds on UV radiation is investigated by the use of ground based measurements from the passive remote sensing instruments operating at this site, mainly broad and moderate narrow band filter radiometers. Cloud modification factors (CMF, ratio between the measured UV radiation in a cloudy sky and the simulated radiation under cloud-free conditions) are evaluated for the study site. CMFs higher than 1 are found during spring and summer time, when lower total ozone columns, higher solar elevations and high cloud cover occur simultaneously, producing extreme erythemal irradiance at the ground surface. Enhancements as high as 25% were registered. The maximum duration of the enhancement was around 30 minutes. This produces dangerous sunbathing conditions for the Río Gallegos citizen.

  13. Investigación sobre manejo forestal a largo plazo en Patagonia Sur -Argentina: Lecciones del pasado, desafíos del presente Long-term forest management research in South Patagonia - Argentina: Lessons from the past, challenges from the present

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    GUILLERMO J MARTÍNEZ-PASTUR

    2010-03-01

    Full Text Available Argentina ha basado su economía en la agricultura y el ganado, donde el bosque ha sido visto como un obstáculo para el desarrollo. La cosecha forestal en Patagonia Sur ha sido una actividad basada en la colonización y explotación de nuevas áreas. Esta se realiza principalmente en bosques primarios sin ningún manejo silvícola posterior. A pesar de que el manejo actual no es sustentable, la investigación científica ha definido las bases para conservar, proteger y mejorar las propuestas de manejo forestal para los bosques nativos de Patagonia Sur. Las primeras parcelas de estudio a largo plazo (1965-1966 basaron su monitoreo en parámetros económicos y estructura forestal, estableciéndose cerca de veinte parcelas en bosques fiscales de Tierra del Fuego. La mayoría fueron destruidas o discontinuadas debido a la falta de planificación del uso de la tierra, escaso interés social en la investigación, falta de compromiso de instituciones, y poca colaboración con empresas forestales. Posteriormente, un segundo grupo de nueve parcelas se estableció en Patagonia Sur (1993-2004 basado en la colaboración entre empresas privadas e instituciones nacionales. Los objetivos incluyeron parámetros económicos y ecológicos. Las parcelas se establecieron en tierras privadas conjuntamente con empresas privadas y estancieros, mediante la firma de acuerdos y proyectos de investigación. Los principales problemas encontrados fueron: falta de compromiso de las administraciones forestales, ausencia de proyectos financiados a largo plazo, y que la responsabilidad de las parcelas continúa bajo la iniciativa personal de los investigadores participantes. El estudio de las parcelas permitió: (i proponer nuevos sistemas de regeneración basados en la maximización del rendimiento y el mejoramiento del valor de conservación de los bosques manejados (e.g., retención variable y sistemas silvopastoriles, (ii determinar la factibilidad económica de aplicaci

  14. LA GEOPEDOLOGIA COMO BASE PARA ZONIFICAR LA APTITUD FORESTAL EN UNA CUENCA DEL NOROESTE DE LA PATAGONIA ARGENTINA

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    Maria Cristina Frugoni

    2016-12-01

    Full Text Available Geopedology at a semi-detailed scale (1:50.000 was carried out in Buta Mallín catchment which includes an area of 21.065ha, in the northwest of Neuquén province, Argentine Patagonia. Geopedology provides a spatial dimension of soil-landscape relations, which are displayed in a map and its legend, showing the geoforms (contours and their soils (content, based on the premise that soil is landscape as well as profile. According to this approach three landscapes were recognized: glacial modeled mountains, plateau and valley. The relief consists mainly of steep to very steep slopes, and valley bottoms with poorly drained soils. Lithology (parent material corresponds to holocene volcanic ash in the western sector of the study area, while the eastern sector is dominated by tuff. Twenty terrain forms and their soils were identified. With this basic information, attribute tables were constructed considering landscape and soil properties. Regarding soils, physical fertility properties were considered, since these are the most correlated ones with Pinus ponderosa (pino ponderosa growth, the main species used in afforestation in Patagonia. Those tables were included and analized with a GIS (Geographic Information System to obtain a forest suitability map. The study area shows four forest suitability classes. Suitable: 37ha; moderately suitable: 4.512ha; marginally suitable: 6.072ha; not suitable: 10.444ha. The main limitations of the area are the very steep slopes, height and the areas dominated by rock outcrops and detrital covers. Nothofagus antarctica (ñire shrubs cover part of the suitable areas; because of conservation criteria of these natural communities, these lands were considered not suitable. On the other side, there are more than 4.000 ha of moderately suitable lands, which can be considered for a more detailed study. Transhumant cattle raising is the main land use system in this catchment, which is an ancient culture of the Northern Neuquian

  15. CO2 and CH4 fluxes of contrasting pristine bogs in southern Patagonia (Tierra del Fuego, Argentina)

    Science.gov (United States)

    Münchberger, Wiebke; Blodau, Christian; Kleinebecker, Till; Pancotto, Veronica

    2015-04-01

    South Patagonian peatlands cover a wide range of the southern terrestrial area and thus are an important component of the terrestrial global carbon cycle. These extremely southern ecosystems have been accumulating organic material since the last glaciation up to now and are - in contrast to northern hemisphere bogs - virtually unaffected by human activities. So far, little attention has been given to these pristine ecosystems and great carbon reservoirs which will potentially be affected by climate change. We aim to fill the knowledge gap in the quantity of carbon released from these bogs and in what controls their fluxes. We study the temporal and spatial variability of carbon fluxes in two contrasting bog ecosystems in southern Patagonia, Tierra del Fuego. Sphagnum-dominated bog ecosystems in Tierra del Fuego are similar to the ones on the northern hemisphere, while cushion plant-dominated bogs can almost exclusively be found in southern Patagonia. These unique cushion plant-dominated bogs are found close to the coast and their occurrence changes gradually to Sphagnum-dominated bogs with increasing distance from the coast. We conduct closed chamber measurements and record relevant environmental variables for CO2 and CH4 fluxes during two austral vegetation periods from December to April. Chamber measurements are performed on microforms representing the main vegetation units of the studied bogs. Gas concentrations are measured with a fast analyzer (Los Gatos Ultraportable Greenhouse Gas Analyzer) allowing to accurately record CH4 fluxes in the ppm range. We present preliminary results of the carbon flux variability from south Patagonian peat bogs and give insights into their environmental controls. Carbon fluxes of these two bog types appear to be highly different. In contrast to Sphagnum-dominated bogs, cushion plant-dominated bogs release almost no CH4 while their CO2 flux in both, photosynthesis and respiration, can be twice as high as for Sphagnum

  16. Traditional Mapuche ecological knowledge in Patagonia, Argentina: fishes and other living beings inhabiting continental waters, as a reflection of processes of change.

    Science.gov (United States)

    Aigo, Juana; Ladio, Ana

    2016-12-07

    Understanding how people interpret environmental change and develop practices in response to such change is essential to comprehend human resource use. In the cosmology of the American indigenous peoples, as among the Mapuche people, freshwater systems are considered a living entity, where animals have an enormous role to play in the universe of meaning. However, human adaptive responses to freshwater system dynamics are scarcely examined. In this work a survey is carried out in three Mapuche communities of Argentine Patagonia to assess their traditional knowledge of the fishes and other non-human living beings that inhabit lakes and rivers. Both material and symbolic aspects are included, as are the differences in knowledge and use of the fishes between past and present times. Our methods were based on a quali-quantitative fieldwork approach. In-depth interviews were carried out with 36 individuals from three rural Mapuche populations in Neuquén province (Patagonia, Argentina). Free listing was used for inquiring about fish knowledge and use. Fishes were identified scientifically and ethnotaxonomically. In-depth analysis of the discourses was conducted, documenting the recognition, perception, and cultural significance of fluvial environments and their inhabitants. Quantitative survey results were analyzed with categorical statistical methods. The body of knowledge of the communities studied reflects the socio-environmental changes experienced by Patagonian freshwater bodies. According to local perception, non-human beings live in these water bodies, guarding the environment, and they should not be disturbed. At present, five different fish species are identified, three of which are exotic, having been introduced at the beginning of the 20th century by the white man. These exotic trout (Oncorhynchus mykiss and Salvelinus fontinalis) are considered ill omens, indicators of the white man's presence, and therefore their appearance presages negative events for the

  17. Petrogenesis of volcanic rocks that host the world-class Agsbnd Pb Navidad District, North Patagonian Massif: Comparison with the Jurassic Chon Aike Volcanic Province of Patagonia, Argentina

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    Bouhier, Verónica E.; Franchini, Marta B.; Caffe, Pablo J.; Maydagán, Laura; Rapela, Carlos W.; Paolini, Marcelo

    2017-05-01

    We present the first study of the volcanic rocks of the Cañadón Asfalto Formation that host the Navidad world-class Ag + Pb epithermal district located in the North Patagonian Massif, Patagonia, Argentina. These volcanic and sedimentary rocks were deposited in a lacustrine environment during an extensional tectonic regime associated with the breakup of Gondwana and represent the mafic to intermediate counterparts of the mainly silicic Jurassic Chon Aike Volcanic Province. Lava flows surrounded by autobrecciated carapace were extruded in subaerial conditions, whereas hyaloclastite and peperite facies suggest contemporaneous subaqueous volcanism and sedimentation. LA-ICPMS Usbnd Pb ages of zircon crystals from the volcanic units yielded Middle Jurassic ages of 173.9 ± 1.9 Ma and 170.8 ± 3 Ma. In the Navidad district, volcanic rocks of the Cañadón Asfalto Formation show arc-like signatures including high-K basaltic-andesite to high-K dacite compositions, Rb, Ba and Th enrichment relative to the less mobile HFS elements (Nb, Ta), enrichment in light rare earth elements (LREE), Ysbnd Ti depletion, and high Zr contents. These characteristics could be explained by assimilation of crustal rocks in the Jurassic magmas, which is also supported by the presence of zircon xenocrysts with Permian and Middle-Upper Triassic ages (281.3 Ma, 246.5, 218.1, and 201.3 Ma) and quartz xenocrysts recognized in these volcanic units. Furthermore, Sr and Nd isotope compositions suggest a contribution of crustal components in these Middle Jurassic magmas. High-K basaltic andesite has initial 87Sr/86Sr ratios of 0.70416-0.70658 and ξNd(t) values of -5.3 and -4. High-K dacite and andesite have initial 87Sr/86Sr compositions of 0.70584-0.70601 and ξNd(t) values of -4,1 and -3,2. The range of Pb isotope values (206Pb/204Pb = 18.28-18.37, 207Pb/204Pb = 15.61-15.62, and 208Pb/204Pb = 38.26-38.43) of Navidad volcanic rocks and ore minerals suggest mixing Pb sources with contributions of

  18. Pingüino In-bearing polymetallic vein deposit, Deseado Massif, Patagonia, Argentina: characteristics of mineralization and ore-forming fluids

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    Jovic, Sebastián M.; Guido, Diego M.; Schalamuk, Isidoro B.; Ríos, Francisco J.; Tassinari, Colombo C. G.; Recio, Clemente

    2011-03-01

    The Pingüino deposit, located in the low sulfidation epithermal metallogenetical province of the Deseado Massif, Patagonia, Argentina, represents a distinct deposit type in the region. It evolved through two different mineralization events: an early In-bearing polymetallic event that introduced In, Zn, Pb, Ag, Cd, Au, As, Cu, Sn, W and Bi represented by complex sulfide mineralogy, and a late Ag-Au quartz-rich vein type that crosscut and overprints the early polymetallic mineralization. The indium-bearing polymetallic mineralization developed in three stages: an early Cu-Au-In-As-Sn-W-Bi stage (Ps1), a Zn-Pb-Ag-In-Cd-Sb stage (Ps2) and a late Zn-In-Cd (Ps3). Indium concentrations in the polymetallic veins show a wide range (3.4 to 1,184 ppm In). The highest indium values (up to 1,184 ppm) relate to the Ps2 mineralization stage, and are associated with Fe-rich sphalerites, although significant In enrichment (up to 159 ppm) is also present in the Ps1 paragenesis associated with Sn-minerals (ferrokesterite and cassiterite). The hydrothermal alteration associated with the polymetallic mineralization is characterized by advanced argillic alteration within the immediate vein zone, and sericitic alteration enveloping the vein zone. Fluid inclusion studies indicate homogenisation temperatures of 308.2-327°C for Ps1 and 255-312.4°C for Ps2, and low to moderate salinities (2 to 5 eq.wt.% NaCl and 4 to 9 eq.wt.% NaCl, respectively). δ34S values of sulfide minerals (+0.76‰ to +3.61‰) indicate a possible magmatic source for the sulfur in the polymetallic mineralization while Pb isotope ratios for the sulfides and magmatic rocks (206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios of 17.379 to 18.502; 15.588 to 15.730 and 38.234 to 38.756, respectively) are consistent with the possibility that the Pb reservoirs for both had the same crustal source. Spatial relationships, hydrothermal alteration styles, S and Pb isotopic data suggest a probable genetic relation between the

  19. Does Type of Substratum Affects Chironomid Larvae Assemblage Composition? A Study in a River Catchment in Northern Patagonia, Argentina.

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    Mauad, M; Siri, A; Donato, M

    2017-02-01

    Chironomid larvae assemblages were investigated at seven sampling stations in relation to stream habitat type in the Challhuaco-Ñireco river system located in the Nahuel Huapi National Park, in the North-Western part of Rio Negro Province, Argentina. A total of 2229 individuals were sampled and 43 Chironomidae taxa were recorded with Orthocladiinae (29) being the best represented subfamily, followed by Diamesinae (5), Tanypodinae (3), Podonominae (3) and Chironominae (3). Stictocladius spF, Cricotopus (Paratrichocladius) sp6, Cricotopus sp2, Cricotopus sp3 and Parapsectrocladius sp2 were the most abundant taxa. Sites near the source of the river system were dominated by Podonomus sp., Limnophyes sp., Parapsectrocladius sp. and Stictocladius spF, whereas sites close to the river mouth were dominated by Diamesinae sp5 and Cricotopus sp. Rank/abundance plots show that all the analysed sites displayed dominance of some species. Stictocladius spF, Cricotopus sp2, Cricotopus sp3, Cricotopus (Paratrichocladius) sp6, Parapsectrocladius sp. and Limnophyes sp. resulted as dominant species, or being part of a group of dominant species, at least in one sample. Eleven taxa were associated with habitats related with riffle areas and stable substrates with filamentous algae. Species-environment relationships were examined using ordination analysis. Elevation was the most significant environmental variable that explained 22% of the total variability of the chironomid assemblages, showing stronger relationships among sites within an altitudinal gradient than among habitat type. Abundance of chironomids increased from headwaters to the outflow in Nahuel Huapi Lake responding to an altitude gradient as well as some environmental factors such as coarse matter and nutrient concentrations.

  20. Sexual dimorphism in the mandible of the armadillo Chaetophractus villosus (Desmarest, 1804 (Dasypodidae from northern Patagonia, Argentina Dimorfismo sexual da mandíbula do tatu Chaetophractus villosus (Desmarest, 1804 (Dasypodidae do norte da Patagônia Argentina

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    SM. Squarcia

    2009-05-01

    Full Text Available The aim of this study was to study the sexual dimorphism in adult Chaetophractus villosus (Desmarest, 1804, from northern Patagonia, Argentina. Eight mandibular traits were measured in 37 males and 34 females. Univariate and multivariate morphometric analysis were applied to the data set. Results showed that C. villosus was sexually dimorphic, with higher absolute values corresponding to females. The total length of the mandible was the most important variable to discriminate sexes, followed by the height at the level of the last tooth and body length. The percentages of sex discrimination were high, as they were when a new sample (17 males, 13 females was tested. Females have larger mandibles than males independently of their larger cranial size. They also showed a higher degree of correlation between variables, suggesting a more stable shape for the mandible than in males.O presente estudo examinou o dimorfismo sexual dos adultos de Chaetophractus villosus (Desmarest, 1804 do norte da Patagônia Argentina. Oito parâmetros mandibulares foram medidos em 37 machos e 34 fêmeas. Análises morfométricas univariada e multivariada foram aplicadas à série de dados. Os resultados mostraram que C. villosus apresenta dimorfismo sexual, com todos os valores absolutos mais elevados nas fêmeas. O comprimento total da mandíbula foi a variável mais importante para discriminar os sexos, seguidos pela altura no nível dos últimos dentes e pelo comprimento do corpo da mandíbula. As porcentagens de discriminação dos sexos foram elevadas, quando uma amostra nova (17 machos, 13 fêmeas foi testada. As fêmeas têm as mandíbulas maiores que os machos, independentemente de seu tamanho cranial maior. Mostraram também um grau mais elevado de correlação entre variáveis, sugerindo uma forma mais estável para a mandíbula que nos machos.

  1. A Maastrichtian microbial reef and associated limestones in the Roca Formation of Patagonia (Neuquén Province, Argentina

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    W. Kiessling

    2006-08-01

    Full Text Available We describe a small microbial reef and associated limestones occurring in a Maastrichtian transgressive succession of mixed carbonate-siliciclastic lithologies at Sierra Huantraico near Chos Malal (Neuquén, Argentina. Strontium isotope data suggest that the reef is of earliest Maastrichtian age. The small reef (0.8 m thick, 2 m wide is mostly composed of peloidal bindstone, dense stromatolite-cement crusts and thrombolite. Except for some ostracods, no metazoan fossils were found in the reef structure, although the majority of peloids are fecal pellets, probably of larger crustaceans. Small foraminifers with calcite tests and probable green algae have also been noted. Sedimentological data and fossils within and immediately above the reef suggest that the reef was formed in a transgressive systems tract under freshwater to brackish-water conditions. Limestones above the reef are serpulid-bryozoan packstones and intraclast-ooid grainstones. These limestones yield a mixture of typical non-tropical (common serpulids and bryozoans and typical tropical aspects (common dasycladaceans and ooids. This mosaic is explained by salinity fluctuations, which in our case dominate over temperature in determining the grain associations. Wir beschreiben ein kleines mikrobielles Riff, das in der Sierra Hunatraico (Neuquén, Argentinien in einer transgressiven, gemischt siliziklastisch-kalkigen Abfolge gefunden wurde. Nach Strontiumisotopen-Datierung ist das Riff in das unterste Maastrichtium zu stellen. Das kleine Riff (0,8 m Mächtigkeit, 2 m Breite besteht überwiegend aus peloidalem Bindstone, dichten Stromatolith-Zement-Krusten und Thrombolith. Mit Ausnahme von Ostrakoden konnten keine Metazoen in der Riffstruktur nachgewiesen werden, obwohl die Mehrzahl der Peloide als Kotpillen zu interpretieren sind, die vermutlich auf größere Krebse zurückgehen. Kleine Foraminiferen und mögliche Grünalgen sind die einzigen zusätzlich nachweisbaren Eukaryoten

  2. EXPERIENCIA OBRERA, CONSTRUCCIONES SINDICALES Y OR-GANIZACIONES POLÍTICAS DE LA CLASE OBRERA: LOS TRABA-JADORES DE LA PATAGONIA ARGENTINA DURANTE LA DÉCA-DA DEL ‘80

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    Gonzalo Pérez Álvarez

    2015-09-01

    Full Text Available Exploramos la relación entre experiencia obrera y organización partidaria de los trabajadores, a partir del estudio de la experiencia que desarrolla un conjunto de trabajadores afincados en la Patagonia argentina durante el auge del proyecto de promoción industrial para la región. Para ello describiremos algunas experiencias de organización partidaria de grupos obreros, intentando problematizar la búsqueda que realizan estos trabajadores de construir programas políticos propios, los límites y potencialidades que se expresan y el intento de desarrollar propuestas alternativas a las conducciones sindicales tradicionales. Señalamos los momentos de quiebre de esta experiencia, y la relación que guardan con la transformación en la estructura económica de la región. La consolidación hegemónica del neoliberalismo necesitaba la destrucción de las construcciones que pudiesen plantear proyectos alternativos al del capital financiero.Palabras clave: Experiencia, sindicatos, partidos políticos, clase obrera._________________________We explore the relationship between working experience and party organization of workers, from the study of the experience that develops a set of workers settled in Patagonia Argentina during the rise of industrial promotion project for the region. This will describe some experiences of party organization groups of workers, trying to problematize the search performed by these workers to build own political agendas, the limits and potentialities that are expressed and the attempt to develop al-ternative approaches to traditional union lines. Note the break in time of this experience, and how they relate to the transformation in the economic structure of the region. The hegemonic consolidation of neoliberalism needed destruction of buildings that may pose alternative to finance capital projects.Keywords: Experience, trade unions, political parties, working class.

  3. Aplicación de análisis petrológicos para determinar la procedencia de artefactos líricos: metodología y resultados obtenidos en la Patagonia septentrional argentina

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    Alicia S. SANGUINETTI

    2009-12-01

    Full Text Available RESUMEN: Se seleccionaron muestras de materiales líticos superficiales y estratigráficos, procedentes de sitios arqueológicos ubicados sobre ambas márgenes del río Limay entre las localidades de Paso Flores y Piedra del Águila, en la provincia de Río Negro, Patagonia septentrional argentina.Teniendo en cuenta su abundancia y semejanza macroscópica con el material típico de la Cantera- Taller Paso Limay, destacado sitio local, se planteó determinar si se trataba de la misma materia prima y, así, evaluar la distribución regional de la misma utilizando análisis petrográficos y geoquímicos. La aplicación de estas clásicas técnicas petrológicas constituyen la metodología por la cual se logran establecer las características distintivas y detalladas para este material lírico, identificándolo así como una importante y ampliamente utilizada materia prima en la región.ABSTRACT: At Northern Patagonia, Río Negro Province, Argentina, from archeological sites over both margins of Limay River, between Paso Flores and Piedra del Águila localities, surface and stratigraphie lithic materials as artifacts were picked out. Through pétrographie and geochemical analysis rhese samples were compared with typical sources from oustanding Paso Limay quarry-factory and evaluared their regional distriburion. The purpose of this work is to expose the methodology to obtain detailed characterization of this important lithic source marter.

  4. Herencia textil, identidad indígena y recursos económicos en la Patagonia argentina. Estudio de un caso: la comarca de la meseta central de la provincia de Chubut

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    Patricia María Méndez

    2009-01-01

    Full Text Available El presente estudio revela la existencia de una producción textil en la Comarca de la Meseta Central de la Provincia de Chubut (Patagonia Argentina de similares características a las descritas en los documentos históricos a partir del siglo XVI y asociada a los antiguos habitantes de la región Patagónica. Corrobora la antigüedad de saberes y prácticas textiles en la Patagonia Argentina y revela algunas de sus características actuales, aspectos ambos sobre los cuales no existen estudios hasta el presente. A través de un trabajo histórico y etnográfico muestra las particularidades técnicas e instrumentales de esta producción, la transmisión de su saber y su importancia para la economía de las familias de la región en el pasado y en la actualidad. También examina su incidencia en la conformación de la identidad de las elaboraciones y de quienes participan en ellas en el presente. Estas cuestiones son abordadas desde una perspectiva estructural, es decir, que considera la intervención de los aspectos sociales, económicos y políticos en el análisis de tales tópicos, alejándose de una visión primordialista y estática de la cultura.

  5. Desarrollo morfológico y conductual de pollos del aguilucho chico Buteo albigula (Aves: Accipitridae en el noroeste de la Patagonia argentina Morphologic and behavioral development of white-throated hawk Buteo albigula (Aves: Accipitridae nestlings in northwestern Argentine Patagonia

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    VALERIA OJEDA

    2003-09-01

    Full Text Available El desarrollo morfológico y conductual del aguilucho chico (Buteo albigula en el nido fue estudiado en cercanías de San Carlos de Bariloche, al noroeste de la Patagonia argentina. El estudio se basó en el seguimiento de dos pollos producidos en diferentes nidos en la temporada reproductiva 2001-2002, y se lo complementó con datos tomados ad libitum en otros nidos, esa misma y anteriores temporadas. Los pollos permanecieron en el nido por aproximadamente seis semanas. Durante su desarrollo morfológico se evidenciaron diversos cambios; notablemente, la aparición secuencial de dos plumones natales, que solo fue observada entre especies de Buteo neotropicales, para B. brachyurus. La conducta de los pollos se encuadró en los patrones comunes para otras especies de Buteo de tamaño corporal similar. Además, se caracterizó, por primera vez para la Argentina, un juvenil (muerto accidentalmente, y se tomaron medidas y peso (por primera vez para B. albigula de dos adultos anillados cerca de sus nidos. El juvenil fue relativamente similar al descrito en Chile. Los adultos, que serían los primeros aguiluchos chicos en ser anillados, se suman a los escasos ejemplares medidos en el área reproductiva conocida de la especie.The morphological and behavioral development of white-throated hawk (Buteo albigula nestlings was studied near San Carlos de Bariloche, in northwestern Argentine Patagonia. The study was mainly based on the monitoring of two nestlings produced at different nests during 2001-2002 breeding season, and was reinforced with data obtained at libitum in other nests the same and previous breeding seasons. The nestling period extended for approximately 6 weeks. Morphological development was characterized by several changing features, but the most surprising was the development of first and second natal down, which was only known, among Neotropical Buteo species, for B. brachyurus. Nestling behavioral development matched the general

  6. Propiedades microbiológicas en un suelo de la patagonia argentina bajo la influencia de diferentes especies forestales Microbiological properties of a soil of the argentine patagonia under the influence of different tree species

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    Diana Noemí Effron

    2011-12-01

    bacterias totales y amilolíticas, podría favorecer una mayor descomposición del residuo vegetal aportado al suelo y explicar los mayores valores de carbono orgánico y respiración microbiana obtenidos.In forest systems, leaf litter is usually the main source of nutrients for the vegetation and microorganisms. Leaf litter composition may vary according to the biomass and quality of the materials produced by different species. Tree roots affect the development and activity of microflora. The aim of this study was to evaluate the influence of two implanted tree species, with different composition of plant residues, on the soil characteristics. The soil is classified as an Andisol and is located in the Trevelín Forest Station, Chubut, Argentina, Lat. 43° S, Long 71º31' West. The samples were extracted from the surface soil of two forest plots with a dominant species each: Radiata Pine (Pinus radiata D. Don. and European Oak (Quercus robur. The following analytical determinations were carried out on soil samples: organic carbon, microbial respiration, deshydrogenase activity, microbial count (bacterial communities, amilolytic, actinomyces and fungi as well as the functional diversity of associated microbial communities. The Shannon-Weaver index (H was calculated. The soil under Oak trees showed the highest values of microbial respiration, organic carbon and amilolytic and bacterial community counts. No significant differences were found in deshydrogenase activity, actinomyces and fungi counts between species. The principal component analysis showed significant variations in the physiology of microbial communities associated with these two tree species. The microorganism H diversity index was significantly greater for Pine. Plants residues of broadleaf species such as Oak have lower contents of recalcitrant substances than conifer species, and this fact, associated with the higher development of total and amylolytic bacteria, could result in an increase in the

  7. The diet of the South American sea lion (Otaria flavescens at Río Negro, Patagonia, Argentina, during the winter-spring period Dieta del lobo marino de un pelo sudamericano (Otaria flavescens en Río Negro, Patagonia, Argentina, durante el invierno y primavera

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    Raimundo L. Bustos

    2012-12-01

    Full Text Available The South American sea lion, Otaria flavescens (Shaw, 1800 population is steadily expanding along the Patagonian coast of Argentina in the last decades. However, little is known about the feeding ecology of the species in the area. The aim of this study was to analyze the food habits of O. flavescens from 91 scats collected at Río Negro province, during the winter and spring of 2005. Fish occurred in 96% of scats containing prey remains, followed by cephalopods (26%. Raneya brasiliensis (Kaup, 1856 was the most frequent and abundant species occurring in 58.6% of samples and constituting almost 50% of fish predated. Second in importance were Porichthys porosissimus (Cuvier, 1829 and Cynoscion guatucupa (Cuvier, 1830 in terms of occurrence (%FO 20.7 and numbers (29.6% respectively. The squid Loligo gahi (d'Orbigny, 1835 was the most frequent cephalopod prey (42.1%, whereas Octopus tehuelchus (d'Orbigny, 1834 was the most abundant (77%. The higher amount and diversity of prey found in the spring in comparison with the winter season might be related to a higher feeding activity of seals or to a seasonal increase in food availability in the area.La población del lobo marino de un pelo sudamericano Otaria flavescens (Shaw, 1800 ha experimentado un crecimiento continuo en las ultimas décadas en las costas de la Patagonia Argentina. Sin embargo, poco se conoce sobre la ecología trófica de la especie en el área. El objetivo de este estudio fue analizar los hábitos alimentarios de O. flavescens a partir de 91 fecas colectadas en la provincia de Río Negro, durante el invierno y la primavera del 2005. Los peces estuvieron presentes en el 96% de las fecas que contenían remanentes presas, seguidos por los cefalópodos (26%. Raneya brasiliensis (Kaup, 1856 fue la especie mas frecuente y abundante ocurriendo en el 58.6% de las muestras y constituyendo casi el 50% de los peces predados. Le siguieron en importancia Porichthys porosissimus (Cuvier, 1829 y

  8. Presence of the telescope fish Mendosoma lineatum in Patagonian waters, a new species in the ichthyological fauna from the south-west Atlantic Ocean.

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    Bovcon, N D; Cochia, P D; Ruibal Núñez, J; Vucica, M; Figueroa, D E

    2017-10-01

    The presence of the telescope fish Mendosoma lineatum in Patagonian waters of Argentina is reported. Mendosoma lineatum is the second species of the Latridae recorded in the south-west Atlantic Ocean and its presence in Patagonia is an addition to both the ichthyological fauna of the Argentinean Sea and the south-west Atlantic Ocean. © 2017 The Fisheries Society of the British Isles.

  9. Especies de Ulva del Golfo San Jorge, Patagonia Argentina: variaciones bioquímicas estacionales - espaciales y su relación con la producción de metabolitos bioactivos

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    Analía Verónica Uhrich

    Full Text Available Objetivos: Investigar especies de Ulva del Golfo San Jorge, Patagonia Argentina, integrando aspectos bioquímicos, actividad biológica y variaciones estacionales/habitacionales que permitan determinar su potencial aplicación en Salud. Métodos: Las algas se colectaron estacionalmente en playas con y sin contaminación antrópica; se secaron, molieron y extrajeron con etanol. Los extractos se fraccionaron mediante solventes de distinta polaridad. Cada fracción fue caracterizada mediante reacciones químicas cualitativas y cromatografía. Las fracciones ricas en flavonoides se analizaron por HPLC-DAD y los lípidos, por TLC. La actividad biológica se ensayó mediante el test de citotoxicidad de Artemia salina, inhibición de la elongación radicular, inhibición de la xantino oxidasa, actividad antioxidante y antibacteriana. Resultados: Se identificaron Ulva rigida y Ulva lactuca. Ambas evidenciaron flavonoides, taninos, quinonas, lípidos, carbohidratos, esteroides. Los flavonoides resultaron mayoritarios en U. rigida (otoño e invierno y en U. lactuca (primavera e invierno, destacándose kayaflavona. Se detectaron alcaloides en Ulva rigida (verano. Los lípidos fueron mayoritarios en verano; U. lactuca en invierno mostró monogalactosildiacilglicérido y en otoño, digalactosilacilglicérido y fosfatidilcolina. La actividad inhibitoria de la elongación radicular, que presume actividad antitumoral, fue importante y dosis dependiente, destacándose U. rigida de otoño y primavera (DE50= 480 y 520 µg/ml, respectivamente. Las demás bioactividades resultaron escasas o negativas. Conclusiones: Las variaciones metabólicas observadas muestran la importancia de considerar las condiciones espacio - temporales al planificar una colecta de ejemplares para su estudio y/o aplicación. Este primer análisis integral de especies de Ulva de la Patagonia Argentina, evidencia su potencialidad como antitumoral.

  10. Reptile and rodent parasites in raptor pellets in an archaeological context: the case of Epullán Chica (northwestern Patagonia, Argentina)

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    Beltrame, María Ornela; Fernández, Fernando Julián; Sardella, Norma Haydeé

    2015-07-01

    Paleoparasitology is the study of parasite remains from archaeological and paleontological sites. Raptor pellets can be used as source for paleoparasitological information in archaeological sites. However, this zooarchaeological material has been scarcely studied. Epullán Chica (ECh) is an archaeological site in northwestern Patagonia. This cave yielded remains from more than 2000 years before present. The aim of this paper was to study the parasite remains found in owl pellets from the archaeological site ECh, and to discuss the paleoparasitological findings in an archaeological context. Twenty two raptor pellets were examined for parasites. The pellets were whole processed by rehydration in a 0.5% water solution of trisodium phosphate, followed by homogenization, filtered and processed by spontaneous sedimentation. Eight out of 22 bird pellets examined were positive for parasites from reptiles and rodents. Representatives of 12 parasite taxa were recorded; nine of this parasitic species were reported for the first time from ancient samples from Patagonia. This is the first time that pellets give evidences of ancient reptile parasites from archaeological contexts. It is noteworthy that Late Holocene hunter-gatherers of the upper Limay River basin, could have been exposed to some of these zoonotic parasites. Future paleoparasitological studies on owl pellets may reflect even more the parasitological diversity of all micromammal and reptile species presents in ancient times.

  11. Plankton dynamics and photosynthesis responses in a eutrophic lake in Patagonia (Argentina: influence of grazer abundance and UVR Dinámica del plancton y respuestas fotosintéticas en una laguna eutrófica de Patagonia (Argentina: influencia de la abundancia de herbívoros y RUV

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    Rodrigo J Gonçalves

    2011-01-01

    Full Text Available A natural plankton population from the eutrophic lake Cacique Chiquichano, in the Argentine Patagonia, was monitored for one year to evaluate changes in photosynthetic parameters as a result of exposure to ultraviolet radiation (UVR, 280-400 nm, grazer abundance, and the taxonomic composition of the phytoplankton community. Both physical (temperature, solar radiation and biological (grazers, taxonomic composition, photosynthetic parameters variables fluctuated throughout the study. Crustacean zooplankton showed alternating dominance between cladocerans (Daphnia spinulata and copepods (Metacyclops mendocinus. The phytoplankton community underwent concomitant changes throughout the year, with cyanobacteria and diatoms alternately dominating. In addition, although copepod abundance was not significantly related to changes in phytoplankton, the presence of D. spinulata was significant during periods of more transparent water; these periods were dominated by diatoms. On the other hand, cyanobacteria dominated the phytoplankton assemblage when the penetration of solar radiation into the water column was lower. Photosynthetic inhibition due to UVR decreased during the diatom-dominated periods. In contrast, inhibition increased along with the proportion of cyanobacteria, likely as a result of acclimation to low irradiance during the lake's phase of lower transparency. Moreover, the presence of D. spinulata was associated with the increased penetration of solar radiation into the water column, resulting in an indirect increment in the inhibition of cyanobacteria photosynthesis. The results suggest that both solar radiation and grazing abundance strongly influence the dynamics and photosynthetic activity of the phytoplankton in Lake Cacique Chiquichano.Se estudió a lo largo del año una comunidad planctónica natural de la laguna eutrófica Cacique Chiquichano de Patagonia-Argentina, para evaluar los cambios en parámetros fotosintéticos como resultados

  12. Ventajas competitivas: Una propuesta paso a paso de búsqueda y aplicación de cadena de valor adaptada a empresas aéreas. Caso Patagonia- Argentina

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    María Alejandra Gazzera

    2005-05-01

    Full Text Available El desarrollo del proceso de búsqueda de ventajas competitivas de una empresa se puede plantear como un esfuerzo que se sigue en tres grandes líneas de actuación: la búsqueda centrada en la empresa, centrada en el entorno, y centrada en los competidores. Si bien la búsqueda de ventajas competitivas está estrechamente interrelacionada y vinculada entre las tres líneas, el presente trabajo se centrará en la primera de ellas, es decir al interior de la empresa, sin perder de vista la relación que tienen las empresas con su entorno o mercado, mediante la aplicación de la cadena de valor de Michael Porter (1985 adaptada a las empresas aéreas que operaban desde y hacia la ciudad de Neuquen, puerta de entrada a la Patagonia Argentina Es necesario destacar que no existen al presente, año 2005, estudios de este tipo en el sector mencionado en Argentina, pero en otros sectores productivos y aún en empresas aéreas de otros países, la cadena de valor ha demostrado su utilidad como tecnología de reflexión estratégica para generar valor en el cliente y para dirigir los esfuerzos de la empresa hacia la consolidación o creación de ventajas competitivas sostenibles en el tiempo.

  13. "Acá nunca pasa nada" Trelew (Patagonia Argentina y Vitoria (País Vasco, España. Polos de desarrollo, dictaduras y la intención de borrar la historia.

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    Pérez Álvarez, Gonzalo

    2016-12-01

    Full Text Available Este artículo rastrea el paralelo observado entre los procesos de instalación de polos de desarrollo en Argentina y España, impuestos durante dictaduras en las décadas del '60 y '70, la intención de sostener una narración histórica que ocultase el conflicto en las regiones intervenidas, y las prácticas obreras que hacían evidente la presencia de la lucha y el cambio, justamente allí donde los discursos oficiales pretendían imponer que "nunca pasaba nada". Mostramos que el ocultamiento de la historia, y por lo tanto del conflicto, era necesario a las dictaduras y a sus pretensiones de planificar, de manera autoritaria, el modelo de desarrollo que estas regiones debían llevar adelante. Para ello rastreamos el proceso en dos ciudades claramente diferentes y muy alejadas entre sí: Trelew, en la región central de la Patagonia Argentina, y Vitoria, la provincia más al sur del País Vasco. Así evidenciamos una de las características de las dictaduras en las ciudades pequeñas: una pretensión de regir los destinos de todo y de todos, hasta el punto de pretender sancionar que en esos lugares no existía la historia, y que eran ellos quienes planificarían su futuro. Pero los trabajadores tendrían otras cosas para decir.

  14. Análisis de sistema de conversores fluido-dinámicos de energía renovable para la Patagonia Austral de Argentina

    OpenAIRE

    Carlos Victor Manuel Labriola; Cecilia Elizabeth Peralta

    2014-01-01

    El potencial de energía en mares y océanos se puede clasificar de distintas formas, por ejemplo: * La energía de las mareas ó Mareomotriz * La energía de las corrientes marinas * La energía de las olas ó Undimotriz * La energía térmica oceánica (OTEC). De estas formas de energía oceánica, tres son posibles en la zona Atlántica de nuestra Patagonia Austral, la Mareomotriz, la Undimotriz y la de corrientes marinas. La Energía Mareomotriz se da desde Viedma hasta Tierra del Fuego con amplitudes ...

  15. Fouling community dominated by Metridium senile (Cnidaria: Anthozoa: Actiniaria in Bahía San Julián (southern Patagonia, Argentina

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    Juan Pablo Martin

    2015-06-01

    Full Text Available The objective of this study is to provide information about a harbour-fouling community dominated by Metridium senile in southern Patagonia. Several steel tubes from the wharf of Puerto San Julián were extracted to perform repair tasks, allowing the attached benthic community to be studied. Sampling was conducted at three levels: lower intertidal, 3-4 m depth and 6-7 m depth. In the lower intertidal, M. senile had a relative abundance of 43%, the most abundant accompanying species being Perumytilus purpuratus, Mytilus edulis platensis and Aulacomya atra atra. At subtidal level, the anemone showed relative abundances of 64% and 65%, and was accompanied by Monocorophium insidiosum at 3-4 m depth and by polychaetes of families Sabellidae and Syllidae at 6-7 m at depth. In the lower intertidal, epibiosis was more frequent on P. purpuratus, A. atra atra and M. edulis platensis, while in the subtidal, the richness of substrate-organisms increased significantly and the anemone was fixed to A. atra atra, M. edulis platensis, Paramolgula gregaria, Crepipatella dilatata, Austromegabalanus psittacus, Hiatella arctica, Polyzoa opuntia, Pyura sp. and Sabellidae tubes. The ability of M. senile to settle on many different organisms, along with other strategies, makes it a colonizer able to displace other species that could compete with it for substratum. Given the cosmopolitan nature of M. senile, the fact that this species has not been previously reported in the coastal zone of the region, and the results of our study, we discuss the possibility that this sea anemone is an invasive alien species in southern Patagonia, or at least a cryptogenic species.

  16. Combined U-Pb SHRIMP and Hf isotope study of the Late Paleozoic Yaminué Complex, Rio Negro Province, Argentina: Implications for the origin and evolution of the Patagonia composite terrane

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    Carlos J. Chernicoff

    2013-01-01

    Combining geological and isotope data, as well as geophysical models, we identify the Yaminué Complex within the La Esperanza-Yaminué crustal block flanked by two other, distinct crustal blocks: the Eastern block which forms part of the Patagonia terrane sensu stricto, located in the eastern Patagonian region, and the Western block forming part of the Southern Patagonia terrane. Their origins and timing of amalgamation to form the Patagonia composite terrane are also discussed.

  17. Presencia de Diaphorina citri (Hemiptera: Psyllidae en el Noroeste Argentino (NOA Record of Diaphorina citri (Hemiptera: Psyllidae in North West Argentina

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    Lucrecia Augier

    2006-12-01

    Full Text Available Se amplía la distribución de Diaphorina citri Kuwayama (Hemiptera: Psyllidae para el Noroeste Argentino.The distribution of Diaphorina citri Kuwayama (Hemiptera: Psyllidae is expanded to North West Argentina.

  18. Análisis de sistema de conversores fluido-dinámicos de energía renovable para la Patagonia Austral de Argentina

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    Carlos Victor Manuel Labriola

    2014-06-01

    Full Text Available El potencial de energía en mares y océanos se puede clasificar de distintas formas, por ejemplo: * La energía de las mareas ó Mareomotriz * La energía de las corrientes marinas * La energía de las olas ó Undimotriz * La energía térmica oceánica (OTEC. De estas formas de energía oceánica, tres son posibles en la zona Atlántica de nuestra Patagonia Austral, la Mareomotriz, la Undimotriz y la de corrientes marinas. La Energía Mareomotriz se da desde Viedma hasta Tierra del Fuego con amplitudes de mareas de 4m hasta 20m, la Energía de las Olas se da en la costa de Chubut y Santa Cruz con potenciales de 10 a 30kW/m lineal de frente de ola y el aprovechamiento de las corrientes marinas se puede dar en lugares puntuales como ser la desembocadura del río Deseado o la de Río Gallegos. Para estas Fuentes de Energía se está realizando un banco de pruebas de modelos conversores de las mismas a Energía Eléctrica, en la Unidad Académica Caleta Olivia (UACO de la Universidad Nacional de la Patagonia Austral (UNPA. Este banco dispondrá de dos canales de ensayos hidrodinámicos uno para energía de las corrientes marinas y otro para las olas. El primero dispondrá de una bomba de circulación con velocidad de fluido variable entre 0 y 4m/s. El banco para olas tendrá un sistema de batido del agua para producir ondas de amplitud y período variable. Además se están dimensionando dos modelos de conversores de energía oceánica. Uno es una turbina, tipo eólica sumergida y el otro modelo es de tubo electromecánico oscilante como conversor energético de las olas.

  19. West Nile and st. Louis encephalitis viruses antibodies surveillance in captive and free-ranging birds of prey from Argentina.

    Science.gov (United States)

    Quaglia, Agustin I; Diaz, Luis A; Argibay, Hernan; Contigiani, Marta S; Saggese, Miguel D

    2014-12-01

    We evaluated the prevalence of WNV and SLEV neutralizing antibodies in captive and free-ranging raptors from Argentina by plaque-reduction neutralization test. Eighty plasma samples from 12 species were analyzed. Only one captive adult Crowned Eagle (Harpyhaliaetus coronatus) was WNV seropositive (prevalence: 1.25%; antibody titer of 1:80). Two captive Crowned Eagles were SLEV seropositive (prevalence: 2.50%; antibody titers: 1:80 and 1:40).These findings expand the geographic distribution of WNV and SLEV and confirm their activity in central and northeastern Argentina. West Nile virus activity in Argentina may represent a potential threat to Crowned Eagles and other endangered raptors in this country.

  20. Argentina

    Energy Technology Data Exchange (ETDEWEB)

    1999-09-01

    This report presents a brief overview of the socio-economic, energy and environmental context in which climate change mitigation actions in Argentina shall be inserted. To that end, the dynamic of the Argentine economic development, its influence on the energy system and environmental impacts is summarised. From the environmental standpoint, emphasis shall only be made on the impact of economic development patterns and energy policies on GHG emission. (au) 73 refs.

  1. Living in an estuary: Commerson's dolphin (Cephalorhynchus commersonii (Lacépède, 1804, habitat use and behavioural pattern at the Santa Cruz River, Patagonia, Argentina

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    Rocio Loizaga de Castro

    2013-11-01

    Full Text Available Commerson's dolphins, Cephalorhynchus commersonii, suffer bycatch in fisheries and are target of dolphin-watching activities along Patagonia. Here we described dolphins' habitat use and behavioural pattern at the estuary of Santa Cruz River. Behavioural observations were made from vantage points using a spotting scope. Boat surveys were conducted randomly from Puerto Santa Cruz to the mouth of the river to analyze the habitat use. The survey area was divided into 1 km² cells and characterized with depth and benthic slope. The described behaviours for the Commerson's dolphin were: travelling, slow travelling, milling, resting, socializing, stationary swimming and diving. A new behavioural context was assigned to diving, a behaviour that showed a high frequency during downing tide, suggesting a benthic foraging strategy. Additionally, we found a strong influence of the tide on Commerson's dolphin behaviour. Habitat use models indicated that dolphins prefer shallow water inside the estuary. The knowledge of the behavioural patterns and the habitat use of these endemic species, in this unexplored area, provide tools for management and conservation purposes.

  2. Ordenamiento Territorial y Turismo en Conservación. Área Salitral de Santa Rosa y Salinas de Trapalcó. Patagonia Argentina.

    OpenAIRE

    MASTROCOLA, YUSARA ISIS

    2016-01-01

    [EN] 100 kilometers southwest from Lamarque (Rio Negro-Argentina), in proximity to Bajo Santa Rosa and Salinas de Trapalcó, there are very rich fossil deposits that give the area a high potential for geopaleontological investigations. The field work carried out by different groups of scientists have allowed to increase and diversify the paleontological heritage of Rio Negro province. In the area there is a succession of Upper Cretaceous sediments including a lower unit of continental ori...

  3. Does Nature and Persistence of Substrate at a Mesohabitat Scale Matter for Chironomidae Assemblages? a Study of Two Perennial Mountain Streams in Patagonia, Argentina

    Science.gov (United States)

    Epele, Luis Beltrán; Miserendino, María Laura; Brand, Cecilia

    2012-01-01

    of the Chironomidae assemblage at the habitat scale is significant for conservation purposes and for the management of low order streams in Patagonia. PMID:22947060

  4. Subduction of the South Chile active spreading ridge: A 17 Ma to 3 Ma magmatic record in central Patagonia (western edge of Meseta del Lago Buenos Aires, Argentina)

    Science.gov (United States)

    Boutonnet, E.; Arnaud, N.; Guivel, C.; Lagabrielle, Y.; Scalabrino, B.; Espinoza, F.

    2010-01-01

    The Chile Triple Junction is a natural laboratory to study the interactions between magmatism and tectonics during the subduction of an active spreading ridge beneath a continent. The MLBA plateau (Meseta del Lago Buenos Aires) is one of the Neogene alkali basaltic plateaus located in the back-arc region of the Andean Cordillera at the latitude of the current Chile Triple Junction. The genesis of MLBA can be related with successive opening of slabs windows beneath Patagonia: within the subducting Nazca Plate itself and between the Nazca and Antarctic plates. Detailed 40Ar/ 39Ar dating and geochemical analysis of bimodal magmatism from the western flank of the MLBA show major changes in the back-arc magmatism which occurred between 14.5 Ma and 12.5 Ma with the transition from calc-alkaline lavas (Cerro Plomo) to alkaline lavas (MLBA) in relation with slab window opening. In a second step, at 4-3 Ma, alkaline felsic intrusions were emplaced in the western flank of the MLBA coevally with the MLBA basalts with which they are genetically related. These late OIB-like alkaline to transitional basalts were generated by partial melting of the subslab asthenosphere of the subducting Nazca plate during the opening of the South Chile spreading ridge-related slab window. These basalts differentiated with small amounts of assimilation in shallow magma chambers emplaced along transtensional to extensional zones. The close association of bimodal magmatism with extensional tectonic features in the western MLBA is a strong support to the model of Patagonian collapse event proposed to have taken place between 5 and 3 Ma as a consequence of the presence of the asthenospheric window (SCR-1 segment of South Chile Ridge) below the MLBA area.

  5. Tafonomía del titanosaurio Aeolosaurus colhuehuapensis, Cretácico Superior, Patagonia central, Argentina: un ejemplo de preservación en facies fluviales de desbordamiento

    OpenAIRE

    Gabriel A Casal; Ibiricu, Lucio Manuel; Allard, Jose Oscar; Martínez, Rubén D.; Luna, Marcelo; Gonzalez Riga, Bernardo Javier

    2016-01-01

    Aeolosaurus colhuehuapensis es un titanosaurio procedente del lago Colhué Huapi, en el Sur de Chubut, Argentina. Los materiales estudiados incluyen veintiuna vértebras caudales y siete hemapófisis, y se hallaron articulados en facies correspondientes a depósitos de desbordamientos vinculados a sistemas fluviales multicanalizados y de alta sinuosidad presentes en los aquí denominados ?estratos del lago Colhué Huapi? de edad Campaniano-Maastrichtiano. Estos sistemas poseían importantes fluctuac...

  6. Distribution and reproductive biology of the Electric ray Discopyge tschudii Heckel, 1846 in San Matías Gulf, Northern Patagonia, Argentina

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    Marilú Estalles

    Full Text Available The Electric ray Discopyge tschudii is distributed in the Southwest Atlantic from southern Brazil to southern Argentina and in the Southeast Pacific from Peru to southern Chile. The main threat to this species is fishing. Discopyge tschudii is noncommercial and individuals caught are discarded on board. The present study analyzes the distribution and the morphological and reproductive characteristics of this ray in San Matías Gulf (SMG, Argentina. A total of 1087 individuals were analyzed. The species presented an aggregate distribution, with the main concentrations in the northern and eastern areas of SMG, at depths below 100 m. Males ranged from 9 to 43 cm and females from 11 to 38 cm. The species presented sexual dimorphism. Males were larger and heavier than females and also matured at larger sizes. Size at 50% of maturity was estimated at 30 cm for males and 21 cm for females. A total of 199 embryos were sampled and the proportion of sexes showed no significant differences from the expected 1:1. The number of embryos per female varied from 1 to 12. The most frequent values were 2 and 5. Length at birth was estimated at 82.17 ± 3.87 mm. Based on our findings, we hypothesize that the electric ray D. tschudii completes its reproductive cycle in SMG.

  7. Historical Glacier Variations in Southern South America since the Little Ice Age: Examples from Lago Viedma (Southern Patagonia) and Mendoza (Central Andes), Argentina

    Science.gov (United States)

    Nussbaumer, S. U.; Masiokas, M.; Pitte, P.; Berthier, E.; Guerrido, C.; Luckman, B. H.; Villalba, R.

    2013-12-01

    The evaluation of historical information can give valuable insight into past glacier dynamics, especially before the onset of modern measurements. Early photographs and maps depict changes for selected glaciers in southern South America. Within this study, written documents and pictorial historical records (drawings, sketches, engravings, photographs, chronicles, topographic maps) are analysed critically, with a particular focus on two regions: Lago Viedma (El Chaltén, southern Patagonia, 49.5°S, 73.0°W) and the Río Mendoza basin (Mendoza, central Andes, 33.1°S, 69.9°W). For the Lago Viedma area, early historical data for the end of the 19th century stem from the expedition of the Chilean-Argentinean border commission. In addition, the expedition by the German Scientific Society, conducted between 1910 and 1916, and the later photographs by Alberto M. de Agostini give an excellent depiction of the glaciers. Glaciar Viedma is a calving glacier which shows distinct retreat from 1896 until the present (though with a stationary or possibly advancing glacier front between 1930/31 and 1951/52), similar to the neighbouring glaciers. On the contrary, nearby Glaciar Perito Moreno shows an exceptional behaviour: the glacier front has been advancing during the first half of the 20th century, staying in an advanced position until the present. At the beginning of the 20th century, Robert Helbling explored the Argentinean-Chilean Andes together with his friend Friedrich Reichert. In the summer of 1909/10, they started a detailed survey of the highly glacierized Juncal-Tupungato mountains (Río Mendoza basin), leading to the first accurate topographic map of the area published in 1914. Its outstanding quality allows a comparison with contemporary satellite imagery. The area received attention in 1934, when the sudden drainage of a glacier-dammed lake in the upper Río del Plomo valley caused fatalities and considerable damage to constructions and the Transandine Railway. A

  8. Distribution and reproductive biology of the Electric ray Discopyge tschudii Heckel, 1846 in San Matías Gulf, Northern Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Marilú Estalles

    2011-01-01

    Full Text Available The Electric ray Discopyge tschudii is distributed in the Southwest Atlantic from southern Brazil to southern Argentina and in the Southeast Pacific from Peru to southern Chile. The main threat to this species is fishing. Discopyge tschudii is noncommercial and individuals caught are discarded on board. The present study analyzes the distribution and the morphological and reproductive characteristics of this ray in San Matías Gulf (SMG, Argentina. A total of 1087 individuals were analyzed. The species presented an aggregate distribution, with the main concentrations in the northern and eastern areas of SMG, at depths below 100 m. Males ranged from 9 to 43 cm and females from 11 to 38 cm. The species presented sexual dimorphism. Males were larger and heavier than females and also matured at larger sizes. Size at 50% of maturity was estimated at 30 cm for males and 21 cm for females. A total of 199 embryos were sampled and the proportion of sexes showed no significant differences from the expected 1:1. The number of embryos per female varied from 1 to 12. The most frequent values were 2 and 5. Length at birth was estimated at 82.17 ± 3.87 mm. Based on our findings, we hypothesize that the electric ray D. tschudii completes its reproductive cycle in SMG.La raya eléctrica Discopyge tschudii se distribuye, en el Atlántico Sudoccidental, desde el sur de Brasil hasta el sur de Argentina y en el Pacifico Sudoriental desde Perú al sur de Chile. La principal amenaza para la especie es la pesca. Es una especie sin valor comercial y debido a esto los ejemplares capturados por las embarcaciones pesqueras son descartados a bordo. En el presente estudio se analizan la distribución espacial y las características morfológicas y reproductivas de la especie en el Golfo San Matías (GSM, Argentina. Un total de 1087 ejemplares fueron analizados. La especie presentó una distribución agregada, encontrándose las principales concentraciones en el sector norte

  9. Hallazgo de restos de la serpiente Dinilysia patagonica Smith-Woodward 1901 en una nueva localidad del Santoniano de Patagonia, Argentina

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    Triviño, L. N.

    2015-12-01

    Full Text Available In this study, we describe new remains of the cretaceous snake Dinilysia patagonica from beds of the locality Barreales Norte, Bajo de la Carpa Formation (Upper Santonian, Neuquén province, Argentina. The material comprises the back of a partially preserved skull, articulated with a fragment of the compound bone, atlas and axis. Additionally, six fragments of precloacal vertebrae have been preserved. The assignation to Dinilysia patagonica is based on: large skull, otooccipital with long paraoccipital process adjacent to an elongate supratemporal that extends farther the level of the occipital condyle; well developed sagital crest of parietal bone, continuously joined with the supraoccipital crest; italics I-like prootic; wide, short and robust vertebrae; prezygapophyses long and highly inclined above the horizontal; triangular section of vertebral centrum; reduced prezygapophyseal process; flattened neural arches with straight posterior edge. This material adds a new Upper Cretaceous location for the distribution of the species at the north of the Neuquén River.En este trabajo se describen nuevos restos de la serpiente cretácica Dinilysia patagonica recuperados en la localidad Barreales Norte, Formación Bajo de la Carpa (Santoniano superior, provincia del Neuquén, Argentina. El material comprende la parte posterior de un cráneo parcialmente conservado y articulado con un fragmento del hueso compuesto, atlas y axis. Además, se preservaron seis secciones de columna vertebral con vértebras precloacales. La asignación a Dinilysia patagonica se basa en: cráneo de tamaño grande, otooccipital con largo proceso paraoccipital adosado a un elongado supratemporal que se extiende más allá del nivel del cóndilo occipital; cresta sagital del parietal bien desarrollada y continua con la cresta del supraoccipital; proótico en forma de I cursiva; vértebras anchas, cortas y robustas; prezigapófisis largas y muy inclinadas sobre la horizontal

  10. Argentina

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    G. Benedetti

    2007-01-01

    Full Text Available El presente trabajo tiene como objetivo realizar un diagnóstico ambiental de un sector de la ciudad de Bahía Blanca, Argentina basado en el arbolado urbano de alineación. El arbolado constituye un componente fundamental de los paisajes artifi ciales ya que contribuye al aumento del confort y al mejoramiento de la calidad del medio. En este sentido, actúa como un factor moderador de las condiciones climáticas, la contaminación y la salud de la población. El municipio de la ciudad de Bahía Blanca tiene como proyecto la realización de inventarios del arbolado en los distintos barrios, para lograr optimizar la relación entre la cantidad de ejemplares arbóreos y la densidad poblacional. Es importante considerar la variedad de ejemplares en función del uso del suelo y de las características ambientales de cada sector. Por lo tanto, este trabajo presenta un diseño metodológico para la elaboración del plano verde de la ciudad.

  11. Spatial distribution of Illex argentinus in San Matias Gulf (Northern Patagonia, Argentina) in relation to environmental variables: A contribution to the new interpretation of the population structuring

    Science.gov (United States)

    Crespi-Abril, Augusto C.; Morsan, Enrique M.; Williams, Gabriela N.; Gagliardini, Domingo A.

    2013-03-01

    Traditionally, it was assumed that major spawning activity of Illex argentinus occurs in discrete pulses along the outer-shelf/slope off Argentina/southern Brazil during late-fall/winter and that early life stages develop near the Brazil-Malvinas Confluence (BMC). However, a novel hypothesis of the population structuring of the species was proposed that states that coastal waters may be important as spawning and feeding grounds. Here, we analyzed the spatial distribution of Illex argentinus inside San Matias Gulf based on the position of the CPUE of jiggers in order to improve the knowledge of the population structuring in coastal regions. Squids were mainly concentrated on the northern region of the gulf where favorable oceanographic conditions (e.g. water stratification, chlorophyll-a concentration peaks) to feeding and spawning are present. These results provided empirical evidences that individuals of I. argentinus use Argentinean coastal waters, particularly San Matias Gulf, as permanent feeding and spawning grounds which supports the new hypothesis.

  12. The diet of the South American sea lion (Otaria flavescens at Río Negro, Patagonia, Argentina, during the winter-spring period

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    Raimundo L. Bustos

    2012-12-01

    Full Text Available The South American sea lion, Otaria flavescens (Shaw, 1800 population is steadily expanding along the Patagonian coast of Argentina in the last decades. However, little is known about the feeding ecology of the species in the area. The aim of this study was to analyze the food habits of O. flavescens from 91 scats collected at Río Negro province, during the winter and spring of 2005. Fish occurred in 96% of scats containing prey remains, followed by cephalopods (26%. Raneya brasiliensis (Kaup, 1856 was the most frequent and abundant species occurring in 58.6% of samples and constituting almost 50% of fish predated. Second in importance were Porichthys porosissimus (Cuvier, 1829 and Cynoscion guatucupa (Cuvier, 1830 in terms of occurrence (%FO 20.7 and numbers (29.6% respectively. The squid Loligo gahi (d'Orbigny, 1835 was the most frequent cephalopod prey (42.1%, whereas Octopus tehuelchus (d'Orbigny, 1834 was the most abundant (77%. The higher amount and diversity of prey found in the spring in comparison with the winter season might be related to a higher feeding activity of seals or to a seasonal increase in food availability in the area.

  13. Inventario preliminar y nuevos registros de Psychodidae no Phlebotominae (Diptera, Nematocera para Argentina, con especial referencia a la Patagonia Preliminary inventory and new records of non Phlebotominae Psychodidae (Diptera, Nematocera for Argentina, with special emphasis to the Patagonian region

    Directory of Open Access Journals (Sweden)

    Guillermo H. Omad

    2012-12-01

    Full Text Available La familia Psychodidae incluye pequeños dípteros nematóceros de distribución cosmopolita. Phlebotominae, en virtud de su importancia sanitaria, ha recibido una adecuada atención y han sido descriptas más de 400 especies para América del Sur. Por el contrario, la contraparte no Phlebotominae de la familia ha sido pobremente estudiada y su conocimiento en la región es escaso. El conocimiento de las Psychodidae no Phlebotominae en la Argentina es escaso, ya que el mismo se restringe a 19 especies agrupadas en 9 géneros. El objetivo de este trabajo es presentar una lista actualizada de Psychodidae para Argentina, donde se amplía el número de géneros a 11, con aproximadamente 24 especies, se registran a su vez nueve especies aún no descriptas y se incluyen cuatro nuevos registros para la Argentina: Alepia copelata Quate, Alepia truncata Bravo, Trichomyia aurea Duckhouse y Trichomyia figuieroai Duckhouse; y tres para la provincia de Chubut: Desmioza speciosa (Tonnoir, Nemoneura confraga Quate & Brown y Nemoneura dealbata Tonnoir. Los sitios de muestreo para este trabajo se realizaron en diferentes zonas de las provincias de Chubut (Parque Nacional Los Alerces, Río Negro y Neuquén (Parque Nacional Nahuel Huapi, Buenos Aires y Misiones.The family Psychodidae includes small cosmopolitan nematoceran flies. The Phlebotominae have received widespread attention due to their public health importance, and over 400 species have been described in South America. Nevertheless, the non Phlebotominae members of the family have been poorly studied, and their knowledge in the region is poor. In Argentina, the non Phlebotominae Psychodidae are scarcely known, with 19 recorded species included in 9 genera. The aim of this contribution is to present an updated list of Psychodidae from Argentina, extending the number of genera to 11 with approximately 24 species, including nine as yet undescribed taxa and four new records for the country: Alepia copelata

  14. PLANTAS AROMÁTICAS CON ÓRGANOS SUBTERRÁNEOS DE IMPORTANCIA CULTURAL EN LA PATAGONIA ARGENTINA: UNA APROXIMACIÓN A SUS USOS DESDE LA ETNOBOTÁNICA, LA PERCEPCIÓN SENSORIAL Y LA ANATOMÍA

    Directory of Open Access Journals (Sweden)

    Soledad Molares

    2012-01-01

    Full Text Available Se analiza la etnobotánica y anatomía de cinco especies aromáticas de uso medicinal y/o comestible altamente valoradas en la Patagonia argentina: Valeriana clarionifolia, V. carnosa (Valerianaceae, Azorella monantha, Osmorhiza chilensis y Eryngium paniculatum (Apiaceae. El principal énfasis ha sido la caracterización de las estructuras secretoras de sus órganos subterráneos y su posible vinculación con las percepciones sensoriales y usos dados por los pobladores. El trabajo etnobotánico se realizó en dos comunidades indígenas Mapuches de la Provincia de Neuquén y en otras dos de la Provincia de Chubut, con un total de 53 entrevistas. El trabajo anatómico consistió en la observación estructural y ultraestructural de las estructuras secretoras. Los informantes indicaron que E. paniculatum es principalmente usada para tratar trastornos digestivos y hepáticos, O. chilensis para problemas de la visión y A. monantha como urinaria y antitusiva; además los órganos subterráneos de estas tres especiesse consumen crudos y/o cocidos. Las especies de Valeriana son usadas principalmente como analgésicas, digestivas, antitusivas y en síndromes culturales. El sabor y el aroma son las principales propiedades sensoriales usadas para reconocer y usar las especies de Valeriana y O. chilensis. A. monantha y E. paniculatum son reconocidas por sus características morfológicas, aunque también se valoranpor su sabor y aroma. Las observaciones microscópicas revelan la presencia de cavidades secretoras esquizógenas en O. chilensis, E. paniculatum y A. monantha y abundante presencia de almidón. En las especies de Valeriana se observa la peridermiscon elevado contenido de aceites esenciales como gotas. Se concluye que estas cinco especies poseen atributos organolépticos originados en estructuras anatómicas especializadas, los que en parte explicarían sus empleos alimenticios y/o medicinales.

  15. Sequential development of tidal ravinement surfaces in macro- to hypertidal estuaries with high volcaniclastic input: the Miocene Puerto Madryn Formation (Patagonia, Argentina)

    Science.gov (United States)

    Scasso, Roberto A.; Cuitiño, José I.

    2017-08-01

    The late Miocene beds of the Puerto Madryn Formation (Provincia del Chubut, Argentina) are formed by shallow marine and estuarine sediments. The latter include several tidal-channel infills well exposed on the cliffy coast of the Peninsula Valdés. The Bahía Punta Fósil and Cerro Olazábal paleochannels are end members of these tidal channels and show a fining-upward infilling starting with intraformational channel lag conglomerates above deeply erosional surfaces interpreted as fluvial ravinement surfaces (the erosion surface formed in the purely fluvial or the fluvially dominated part of the estuary, where erosion is driven by fluvial processes). These are overlain and eventually truncated (and suppressed) by the tidal ravinement surface (TRS), in turn covered with high-energy, bioclastic conglomerates mostly formed in the "tidally dominated/fluvially influenced" part of an estuary. Above, large straight or arcuate point bars with alternatively sandy/muddy seasonal beds and varying trace and body fossil contents were deposited from the freshwater fluvially dominated to saline-water tidally dominated part of the estuary. The upper channel infill is formed by cross-bedded sands with mud drapes and seaward-directed paleocurrents, together with barren, volcaniclastic sandy to muddy heterolithic seasonal rhythmites, both deposited in the fluvially dominated part of the estuary. Volcanic ash driven by the rivers after large explosive volcanic eruptions on land resulted in sedimentation rates as high as 0.9 m per year, preserving (through burial) the morphology of tidal channels and TRSs. The channel deposits were formed in a tide-dominated, macrotidal to hypertidal open estuary with well-developed TRSs resulting from strong tidal currents deeply scouring into the transgressive filling of the channels and eventually cutting the fluvial ravinement surface. The TRSs extended upstream to the inner part of the estuary during long periods of low sedimentation rates

  16. New cases of human diphyllobothriosis in Patagonia, Argentine

    Directory of Open Access Journals (Sweden)

    Semenas Liliana

    2001-01-01

    Full Text Available The purpose of the paper is to describe 4 new cases of human diphyllobothriosis in Patagonia, Argentine. Adult parasites recovered were submitted to morphological and histological analyses for taxonomic identification. The etiological agent found was always Diphyllobothrium latum and all the cases were autochthonous. These data combined with previous information make the number of autochthonous human cases of diphyllobothriosis registered in Argentina increase to 18.

  17. New cases of human diphyllobothriosis in Patagonia, Argentine

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    Liliana Semenas

    2001-04-01

    Full Text Available The purpose of the paper is to describe 4 new cases of human diphyllobothriosis in Patagonia, Argentine. Adult parasites recovered were submitted to morphological and histological analyses for taxonomic identification. The etiological agent found was always Diphyllobothrium latum and all the cases were autochthonous. These data combined with previous information make the number of autochthonous human cases of diphyllobothriosis registered in Argentina increase to 18.

  18. Patagonia: nature and territories

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    Alejandro Fabián Schweitzer

    2014-12-01

    This paper analyzes the place occupied by Patagonia in today’s fin de siècle scenario of commodities, hegemony crisis and multi-polar world emergence concurring with the convergence of consumerist guidelines, all of which would apparently lead to an in-depth socio-ecological crisis as well as to an accelerated dispute over nature and territory sense.

  19. The tectonographic development of Patagonia and its relevance to hydrocarbon exploration

    Energy Technology Data Exchange (ETDEWEB)

    Light, M.P.R.; Urien, C.M.; Maslanyj, M.P.; Keeley, M.L.; Hoggs, S.L.

    1993-02-01

    Patagonia accreted successively from the southwest onto the southern margin of the Proterozoic Plata Craton and Brazilian Guapore Shield between the Late Proterozoic and Early Devonian. The thrust-like stacking of terranes onto the southern termination of the Pelotas Terrane is considered to have developed a pervasive northwest to north-trending fabric. During the Permo-Triassic the northwest to north-trending fabric of the Patagonian Plate was re-activated by dextral strike-slip movement causing extension. The deformation was caused by oblique subduction and accretion of the madre Dos Dios to Pichidangui Terranes along its western margin. To the northeast the more competent shield underwent compression (Ventania-Gond-wanide Folding) and extension occurred parallel to the axis of the embryo South Atlantic, where a shallow sea transgressed. Ridge on its western side, now preserved on the facing shelf margins of Argentina and Namibia. In the Late Triassic-Lower Jurassic, the Malvinas and Microplate was situated south of the Transkei (South Africa) and an intracratonic basin separated it from two sutures formed at the margin of the Argentine Shelf and along the axis of the West Malvinas Basin. Subduction/arc activity on the west flank of this intracratonic basin, in association with trench pull is believed to have initiated Late Triassic-Early Jurassic strike slip extension and volcanicity in Patagonia. This exploited the pervasive northwest and north-trending Paleozoic fabric. By the Mid-Jurassic the Malvinas Microplate had docked with the eastern margin of the Patagonian Shelf and was undergoing clockwise rotation between the Malvinas-Agulhas and Burwood Bank-Scotia Ridge dextral strike-slip systems. Rifting had now progressed southwestwards to the Pacific and north eastwards to the Colorado and Outeniqua Basins.

  20. NREL technical assistance to Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Lilienthal, P. [National Renewable Energy Lab., Golden, CO (United States)

    1997-12-01

    This paper describes assistance to Argentina from the National Renewable Energy Laboratory which has touched on four programs: tariff analysis for rural concessions programs; wind/diesel hybrid retrofits in Patagonia; small hybrid systems designs for rural schools; an assessment of wind resources. The paper expands briefly on the first two points.

  1. LA CUEVA ALIHUÉN, NUEVOS REGISTROS DE PINTURAS RUPESTRES EN LA VEGA DE MAIPÚ (SAN MARTÍN DE LOS ANDES, PATAGONIA, ARGENTINA (The Alihuén Cave, New Records of Cave Paintings in the Maipú Valley (San Martín de los Andes, Patagonia, Argentina

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    Alberto Enrique Pérez

    2014-06-01

    Full Text Available Se presenta el resultado de las nuevas investigaciones de pinturas rupestres en la vega Maipú, San Martín de los Andes, Neuquén, Argentina; donde se destaca la presencia de motivos zoomorfos, especialmente camélidos, de escasa representación hasta la fecha en el registro zooarqueológico local. El sitio Cueva Alihuén amplía la diversidad de motivos y técnicas de las pinturas rupestres de la vega Maipú, lo que nos permite plantear aspectos tanto biogeográficos respecto a la fauna como sobre la circulación de información y movilidad. Ambos aspectos nos permiten, nuevamente, aunar ambas vertientes de la cordillera de los Andes, compartiendo, integrando y complementando cada vez más características con el resto de los sitios que componen la cuenca hidrográfica de Valdivia, cuyo sector inferior constituye nuestra área de estudio. ENGLISH: New results from research on the cave paintings of the Maipú Valley, San Martín de los Andes, Neuquén, Argentina, highlight the presence of zoomorphic motifs, especially camelids which have been underrepresented in the local zooarchaeological record. The Alihuén cave site expands the range of motifs and techniques known from the cave paintings of the Maipú Valley that allows us to raise issues regarding both biogeographic wildlife, and on the flow of information and human mobility. These aspects allow us to share and integrate the increasingly complementary features on both sides of the Andes with the rest of the sites that comprise the Valdivia River basin, whose lower section composed our study area.

  2. Nanofósiles calcáreos paleógenos y biostratigrafía para dos pozos en el este de la Cuenca Austral, Patagonia, Argentina Paleogene calcareous nannofossil biostratigraphy for two boreholes in the eastern Austral Basin, Patagonia, Argentina

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    Juan Pablo Pérez Panera

    2013-01-01

    Full Text Available Calcareous nannofossils from two boreholes (Campo Bola and Sur Río Chico in the subsurface of eastern Austral Basin, Santa Cruz Province, Argentina, allowed the identification of Early to Middle Paleocene, Early to Middle Eocene and Late Eocene to Early Oligocene assemblages. These assemblages match the formations logged in the boreholes Campo Bola, Man Aike and Río Leona respectively, and represent three paleogene sedimentary cycles within the basin. These results permitted the reinterpretation of previous data from an adjacent borehole (Cerro Redondo. The southern boreholes (Cerro Redondo and Sur Río Chico yield an Early to Middle Paleocene calcareous nannofossil assemblage and an almost continuous record of nannofossils from Early Eocene to Early Oligocene. A discontinuity is interpreted by the absence of Late Paleocene assemblages. The northern borehole (Campo Bola yield only late Early Eocene to Early Oligocene assemblages. The data also indicates that the Paleogene beds unconformably overlie Upper Cretaceous strata.El estudio de los nanofósiles calcáreos recuperados en muestras de subsuelo de dos pozos de exploración (Campo Bola y Sur Río Chico en el este de la Cuenca Austral, provincia de Santa Cruz, Argentina, permitió reconocer asociaciones del Paleoceno Temprano a Medio, Eoceno Temprano a Medio y Eoceno Tardío a Oligoceno Temprano. Estas asociaciones son coincidentes con las formaciones atravesadas en los sondeos hechos en Campo Bola, Man Aike y Río Leona, respectivamente, y representan tres ciclos sedimentarios paleógenos dentro de la cuenca. Estos resultados permitieron la reinterpretación de datos previos de un pozo adyacente (Cerro Redondo. Los pozos ubicados al sur (Cerro Redondo y Sur Río Chico contienen asociaciones de nanofósiles calcáreos del Paleoceno Temprano a Medio y un registro prácticamente continuo de nanofósiles del Eoceno Temprano al Oligoceno Temprano. Se interpreta una discontinuidad por ausencia de

  3. Treating residual water according to the demands of its ulterior use: case of Neuquen river, Patagonia, Argentina; Optimizacion de requisitos de tratamiento de aguas residuales basado en la calidad del agua de acuerdo con el uso del cuerpo receptor: caso rio Neuquen, Patagonia, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Polla, Gabriela Maria; Dufilho, Ana Cecilia; Horne, Federico [Universidad Nacional del Comahue (Argentina)

    2006-07-15

    A developed methodology allows making a regional pacification based on the river's water quality and their guide levels for different uses. To get this methodology it was used an optimization model that allows obtaining the best combination of town and industrial liquid treatments of the region, which can make cheaper their construction and maintenance costs. The established regional stages of economical development, were simulated with the QUAL2E model, from this model was obtained the restriction coefficients of the optimization model. More over, this model allowed to prognosticate the behavior of the principal water quality components (dissolved and biochemical demand of oxygen, nitrogen, phosphorus and others) for different proposed stages. This methodology was applied over a section of Neuquen River (Argentina) which receives urban, industrial and farming effluents of three cities Centenario (Plant 1), Cinco Saltos (Plant 2) and Parque Industrial (Plant 3). From results, it can be affirmed that under present situation, there is not contamination hazard. However, under future scenarios, advanced and secondary treatment is required to assure meeting the quality standards, particularly when river discharge approach it annual minimum. [Spanish] Se desarrollo una metodologia que permite hacer una planificacion regional basada en la calidad de agua del rio y sus niveles guias para distintos usos. Para ello se utilizo un modelo de optimizacion que permite obtener la mejor combinacion de tratamientos de liquidos municipales e industriales de la region que minimicen sus costos de construccion y mantenimiento. Los escenarios de desarrollo economico regional planteados se simularon con el modelo QUAL2E, de donde se obtuvieron los coeficientes de las restricciones del modelo de optimizacion. El modelo de simulacion permitio, ademas, pronosticar el comportamiento de los principales componentes de calidad del agua (oxigeno disuelto, demanda bioquimica de oxigeno

  4. Impactos de la explotación de reservorios no convencionales de hidrocarburos sobre la actividad industrial y de servicios en el sistema de ciudades. El caso de la Cuenca Neuquina en la Patagonia Argentina / Impacts of the exploitation of unconventional hydrocarbon reservoirs on industrial activity and services in the city system: the case of the Neuquen Basin in Patagonia Argentina

    Directory of Open Access Journals (Sweden)

    Susana Graciela Landriscini

    2016-12-01

    Full Text Available Resumen El presente trabajo expone avances de conocimiento acerca de algunos impactos territoriales, de la exploración y explotación de hidrocarburos de reservorios no convencionales en la Cuenca Neuquina Argentina. Se enfocan los cambios recientes en el sistema de ciudades de la Confluencia Neuquina y en las tramas de empresas que integran la cadena de valor. Ellos se extienden asimismo a localidades rionegrinas asentadas en la Cuenca, extendida hasta el sur de la provincia de Mendoza y el oeste de las provincias de la Pampa y Río Negro. Se retoman debates teóricos sobre las funciones de las ciudades, el peso de la trayectoria y los fenómenos de aglomeración, los cambios que se generan como parte de redes y flujos en tiempos de la globalización; y las cuestiones de la gestión del conocimiento y las capacidades de innovación de las pequeñas y medianas empresas proveedoras de bienes y servicios a los hidrocarburos. Se revisan documentos, planes y programas públicos sobre la región y las relaciones proveedores/clientes en el upstream, y se reflexiona acerca de las tensiones que generan dichos procesos, y las perspectivas de transformación del sistema urbano regional en su actual fase de desarrollo. La evaluación de los cambios urbanos de las actividades relacionadas al upstream, y una amplia gama de servicios directos de distinta intensidad tecnológica, involucran factores regionales y locales en las distintas ciudades, acorde a su localización, funciones, trayectoria histórica regional y de las localidades, y sus posibilidades de integración y diversificación económica. En dicho sistema de organización, Neuquén capital es un centro abastecedor de servicios públicos y privados, sociales, personales y a empresas, de distinto grado de complejidad y alcance regional. En ella se asientan las bases de las empresas de mayor envergadura. Otras ciudades operan como centros de importancia media y atraen firmas pequeñas y medianas; y

  5. Transboundary protected area proposals along the Southern Andes of Chile and Argentina: Status of current efforts

    Science.gov (United States)

    Peter Keller

    2007-01-01

    An evolving network of protected areas along the southern Andes of Chile and Argentina-the heart of Patagonia-are in various stages of evaluation and potential Transboundary Protected Area designations. This paper examines three such efforts. The first proposal is the North Andean-Patagonia Regional Eco-Corridor, which was the subject of a recent bilateral meeting...

  6. The role of stand composition on pre-dispersal seed predation in Austrocedrus chilensis (Cupressaceae in north west Patagonia El rol de la composición del bosque sobre la depredación predispersiva de semillas en Austrocedrus chilensis (Cupressaceae en el noroeste de la Patagonia

    Directory of Open Access Journals (Sweden)

    JOSÉ M VILLACIDE

    2008-09-01

    émica del suroeste de Sudamérica (Chile central y Patagonia chilena y argentina, que crece naturalmente en bosques puros y mixtos típicamente asociada con especies latifoliadas del género Nothofagus. Las semillas de este árbol son atacadas en su fase predispersiva, principalmente por las larvas de Nanodacna austrocedrella (Lepidoptera: Elachistidae. Nuestra hipótesis de trabajo fue que las variaciones observadas en los niveles de daños pre-dispersivos están relacionadas con la composición del bosque, específicamente la proporción de A. chilensis relativa a su acompañante Nothofagus dombeyi. Comparamos los niveles de depredación en seis pares de sitios según un diseño en bloque, incluyendo un bosque mixto y uno puro para cada sitio. En estos, seleccionamos cinco árboles adultos de A. chilensis de los cuales colectamos manualmente 50 conos cerrados por árbol. El nivel de daño predispersivo fue altamente variable, con los valores entre el 16,7 y el 73,0 % de semillas afectadas. Encontramos diferencias significativas en tasas de la depredación según la composición del bosque, siendo siempre mayor el impacto observado en los bosques mixtos que en los bosques puros. Demostramos que la composición del bosque puede determinar el nivel de daño sobre semillas antes de su dispersión, apoyando la hipótesis de mayor daño en bosques mixtos. Nuestro trabajo es el primero en examinar el efecto del tipo del bosque sobre las variaciones espaciales de las tasas de depredación predispersiva de semillas en A. chilensis a escala regional. Esta información puede ser de utilidad en la planificación de cosechas comerciales de semillas de A. chilensis y la conservación esta conifera endémica.

  7. Robles in Lagunas de Epulauquen, Argentina: previous and recent evidence of their distinctive character

    National Research Council Canada - National Science Library

    Azpilicueta, María M; Pastorino, Mario J; Puntieri, Javier; Barbero, Fernando; Martinez-Meier, Alejandro; Marchelli, Paula; Gallo, Leonardo A

    2014-01-01

    The northernmost ‘robles’ of Argentina, located in Lagunas de Epulauquen (northwest Patagonia), are considered a population of Nothofagus obliqua, even though they differ in some respects from individuals of other populations of the species...

  8. The Barrancas anticline in west-central Argentina: new geomorphic and geologic constraints on the geometry and activity of a fault-related fold

    Science.gov (United States)

    Rimando, J. M.; Schoenbohm, L. M.

    2016-12-01

    The Barrancas anticline in Mendoza Province, west-central Argentina is a N-NW-oriented, east-vergent fault-bend fold located in the transition from the mainly east-vergent, thin-skinned Argentine Precordillera to the mainly west-vergent, thick-skinned Sierras Pampeanas — one of the most active thrust zones on Earth. Previous studies of the Barrancas anticline interpreted its structure from 2-D and 3-D seismic data. The anticline is a fault-bend fold with multiple segments with different uplift histories and which linked only after 2.3Ma. This study aims to establish the temporal persistence of segmentation and to describe the role, extent and rates of deformation processes involved in the development of the Barrancas anticline from morphometric analyses, geologic and geomorphic mapping, and accurate dating of relevant geomorphic features. Longitudinal profile analysis of streams on the anticline reveals marked differences in normalized steepness index (ksn) between the western and eastern limbs as well as variation along strike. This distribution of ksn values reveals patterns consistent with asymmetry and segmentation of the Barrancas anticline. Swath profiles parallel to the fold axis resemble fault slip distribution profiles which was a basis for segmentation from previous studies. Drainage basin morphometric indices such as hypsometry, drainage density, and basin elongation were also measured. Hypsometric integral values were particularly higher on the west than on the east, possibly indicating younger folding on the western limb. This study will contribute to a better understanding of the nature, extent, timing, and rate of folding at the transition from thin- to thick-skinned thrust deformation in west-central Argentina. Additionally, this study will contribute to assessment of seismic hazards associated with fault-related folds in Argentina and in similar tectonic settings worldwide.

  9. Use of timesat to estimate phenological parameters in Northwestern Patagonia

    Science.gov (United States)

    Oddi, Facundo; Minotti, Priscilla; Ghermandi, Luciana; Lasaponara, Rosa

    2015-04-01

    Under a global change context, ecosystems are receiving high pressure and the ecology science play a key role for monitoring and assessment of natural resources. To achieve an effective resources management to develop an ecosystem functioning knowledge based on spatio-temporal perspective is useful. Satellite imagery periodically capture the spectral response of the earth and remote sensing have been widely utilized as classification and change detection tool making possible evaluate the intra and inter-annual plant dynamics. Vegetation spectral indices (e.g., NDVI) are particularly suitable to study spatio-temporal processes related to plant phenology and remote sensing specific software, such as TIMESAT, has been developed to carry out time series analysis of spectral indexes. We used TIMESAT software applied to series of 25 years of NDVI bi-monthly composites (240 images covering the period 1982-2006) from the NOAA-AVHRR sensor (8 x 8 km) to assessment plant pheonology over 900000 ha of shrubby-grasslands in the Northwestern of Patagonia, Argentina. The study area corresponds to a Mediterranean environment and is part of a gradient defined by a sharp drop west-east in the precipitation regime (600 mm to 280 mm). We fitted the temporal series of NDVI data to double logistic functions by least-squares methods evaluating three seasonality parameters: a) start of growing season, b) growing season length, c) NDVI seasonal integral. According to fitted models by TIMESAT, start average of growing season was the second half of September (± 10 days) with beginnings latest in the east (dryer areas). The average growing season length was 180 days (± 15 days) without a clear spatial trend. The NDVI seasonal integral showed a clear trend of decrease in west-east direction following the precipitation gradient. The temporal and spatial information allows revealing important patterns of ecological interest, which can be of great importance to environmental monitoring. In this

  10. Regional climate change scenarios applied to viticultural zoning in Mendoza, Argentina

    Science.gov (United States)

    Cabré, María Fernanda; Quénol, Hervé; Nuñez, Mario

    2016-09-01

    Due to the importance of the winemaking sector in Mendoza, Argentina, the assessment of future scenarios for viticulture is of foremost relevance. In this context, it is important to understand how temperature increase and precipitation changes will impact on grapes, because of changes in grapevine phenology and suitability wine-growing regions must be understood as an indicator of climate change. The general objective is to classify the suitable areas of viticulture in Argentina for the current and future climate using the MM5 regional climate change simulations. The spatial distribution of annual mean temperature, annual rainfall, and some bioclimatic indices has been analyzed for the present (1970-1989) and future (2080-2099) climate under SRES A2 emission scenario. In general, according to projected average growing season temperature and Winkler index classification, the regional model estimates (i) a reduction of cool areas, (ii) a westward and southward displacement of intermediate and warm suitability areas, and (iii) the arise of new suitability regions (hot and very hot areas) over Argentina. In addition, an increase of annual accumulated precipitation is projected over the center-west of Argentina. Similar pattern of change is modeled for growing season, but with lower intensity. Furthermore, the evaluation of projected seasonal precipitation shows a little precipitation increase over Cuyo and center of Argentina in summer and a little precipitation decrease over Cuyo and northern Patagonia in winter. Results show that Argentina has a great potential for expansion into new suitable vineyard areas by the end of twenty-first century, particularly due to projected displacement to higher latitudes for most present suitability winegrowing regions. Even though main conclusions are based on one global-regional model downscaling, this approach provides valuable information for implementing proper and diverse adaptation measures in the Argentinean viticultural

  11. Una vuelta a la “casa bonita”. Un bricolage interpretativo de las fuentes documentales sobre los rituales de menarquía de los pueblos originarios de la Patagonia argentina (Siglos XIX y XX

    Directory of Open Access Journals (Sweden)

    Graciela Hernández

    2015-12-01

    Full Text Available El principal objetivo de este trabajo es proponer un nuevo análisis del texto del británico Georges Musters, de su descripción de una ceremonia de menarquía (a la que denominó “casa bonita” observada entre tehuelches de la Patagonia en 1869, para contextualizarla históricamente y desde una perspectiva de género.Desde la metodología cualitativa hemos armado un bricolage que se expresa en un recorrido articulado por una genealogía de fuentes documentales del siglo XIX, por testimonios producidos en trabajos antropológicos y lingüísticos en la segunda mitad del siglo XX, y por registros etnográficos de nuestros trabajos en historia oral que focalizan en  rituales para propiciar el hilado.La triangulación de fuentes de los documentos seleccionados nos lleva a pensar en la hipótesis que en las ceremonias de primera menstruación, del siglo XIX en adelante, se propiciaba el apego al hilado y tejido,  en sociedades que también  ritualizaron toda la esfera del trabajo textil.

  12. Variaciones glaciales durante el Holoceno en Patagonia Central, Aisén, Chile: evidencias geomorfológicas Holocene glacial variations in Central Patagonia, Aisén, Chile: geomorphological evidences

    Directory of Open Access Journals (Sweden)

    María Mardones

    2011-07-01

    en la temperatura y precipitación atmosférica.During the Holocene, the patagonian glaciers were characterized by geomorphologically registered advances and retreats. This paper presents the geomorphological evolution and evidences of Holocene glacial advances within a segment in Central Patagonia Cordillera. This area will be used as a reference for studying the postglacial paleoclimatic evolution in the southernmost part of South America. The study area is the río Blanco basin (45°30'S, located in Central Patagonia (Aisén Region, Chile. Radiometric dating of organic sediments, within terminal moraines, provides preliminary data of two glacial advances. The first one is represented by the Lake Elizalde frontal moraine, which yielded a 14C age of 9.370±50 years BP (10,700 to 10,480 cal. yr BP. According to this chronological age, this glacial event took place in the Early Holocene. This glacial advance, being 100 to 200 years older than that observed immediately south of the study area, on the eastern edge of General Carrera Lake (or Buenos Aires Lake, in Argentina and approximately 100 years younger than the event recorded in the Puerto Banderas I moraine (Argentino Lake, 50°S. These results show that the behavior patterns of the Central Patagonia glaciers differ from that observed both in the Lake District (41°S, Chile and in the Magallanes District (54°S, Chile, where there are no traces of glacial readvancement recorded during the Early Holocene. After a major retreat to the west, a more recent glacial advance occurred in the Quetro river valley (a tributary river of the Blanco river, at an age prior to 2.250±40 BP (2.340 to 2.150 cal. yr BP, comparable to the cold stage of the Middle Neoglacial, interpreted to have occurred in different parts of Patagonia. Confronting these results with previously published pollen records, we postulate that the cause of both glacier fluctuations are regional variations in the atmospheric temperature and precipitations.

  13. Subduction of the South-Chile active spreading ridge: a 17 Ma to 3 Ma magmatic record in central Patagonia (western edge of Meseta del Lago Buenos Aires, Argentina)

    Science.gov (United States)

    Boutonnet, Emmanuelle; Arnaud, Nicolas; Guivel, Christèle; Lagabrielle, Yves; Scalabrino, Bruno; Espinoza, Felipe

    2010-05-01

    The Chile Triple Junction is a natural laboratory to study the interactions between magmatism and tectonics during the subduction of an active spreading ridge beneath a continent. The MLBA plateau (Meseta del Lago Buenos Aires) is one of the Neogene alkali basaltic plateaus located in the back-arc region of the Andean Cordillera at the latitude of the current Chile Triple Junction. The genesis of MLBA can be related with successive opening of slabs windows beneath Patagonia: within the subducting Nazca Plate itself and between the Nazca and Antarctic plates. Detailed 40Ar/39Ar dating and geochemical analysis of bimodal magmatism from the western flank of the MLBA show major changes in the back-arc magmatism which occurred between 14.5 Ma and 12.5 Ma with the transition from calc-alkaline lavas (Cerro Plomo) to alkaline lavas (MLBA) in relation with slab window opening. In a second step, at 4- 3 Ma, alkaline felsic intrusions were emplaced in the western flank of the MLBA coevally with the MLBA basalts with which they are genetically related. These late OIB-like alkaline to transitional basalts were generated by partial melting of the subslab asthenosphere of the subducting Nazca plate during the opening of the South Chile spreading ridge-related slab window. These basalts differentiated with small amounts of assimilation in shallow magma chambers emplaced along transtensional to extensional zones. The close association of bimodal magmatism with extensional tectonic features in the western MLBA is a strong support to the model of Patagonian collapse event proposed to have taken place between 5 and 3 Ma as a consequence of the presence of the asthenospheric window (SCR-1 segment of South Chile Ridge) below the MLBA area.

  14. TAFONOMÍA DE RESTOS ÓSEOS PROVENIENTES DE EGAGRÓPILAS DE CORAGYPS ATRATUS (JOTE DE CABEZA NEGRA EN EL NOROESTE DE LA PATAGONIA ARGENTINA/Taphonomy of bones remains from pellets of Coragyps Atratus (black vulture in the northwest of the argentinian Patag

    Directory of Open Access Journals (Sweden)

    Fernando Ballejo

    2012-11-01

    Full Text Available Existen diversos estudios actualísticos en tafonomía sobre restos de presas de diferentes especies de aves raptoras. Sin embargo, este tipo de trabajos en aves carroñeras ha sido escasamente considerado hasta el momento en Argentina, a pesar que ellas cumplen un papel fundamental en la alteración y transporte de cadáveres. Coragyps atratus (jote de cabeza negra tiene la particularidad de formar posaderos comunales cercanos a áreas de actividades humanas y de alimentarse de animales de todos los tamaños, por lo que pueden interferir en la formación de sitios arqueológicos. El objetivo de este trabajo es realizar un análisis tafonómico sobre los restos óseos recuperados de egagrópilas de C. atratus en el Noroeste patagónico, con el fin de generar herramientas que permitan identificar a estas aves como posibles agentes acumuladores. Se recolectaron 469 egagrópilas distribuidas en tres posaderos del Noroeste patagónico. Se identificaron los elementos recuperados y se evaluaron los grados de alteraciones por ácidos gástricos. Lepus europaeus y Ovis aries dominaron las muestras. Los elementos más representativos pertenecen al autopodio, principalmente falanges. Todos ellos muestran signos de digestión, que van desde porosidades superficiales, perforaciones y fracturas, con la desaparición de la médula en el caso de varias falanges; denotando diferencias en relación al tamaño de la presa consumida. Abstract There are several actualistic taphonomic studies regarding different species of birds of prey. However, the studies focus on scavenger birds have been scarcely considered in Argentina, despite the fact that they play a fundamental role in the alteration and transportation of carcasses. A peculiar characteristic of Coragyps atratus (black vulture is that it builds communal roosts near places where human activities are developed and it feeds on animals of varying size, which may interfere with the formation of archaeological

  15. Permian to late Cenozoic evolution of northern Patagonia: Main tectonic events, magmatic activity, and depositional trends

    Science.gov (United States)

    Uliana, M. A.; Biddle, K. T.

    The late Paleozoic to late Cenozoic evolution of northern Patagonia was influenced significantly by events that occurred while the area was part of the South American sector of Gondwanaland. Late Paleozoic to Middle Triassic subduction along the edge of the supercontinent formed a broad convergent-margin system that is the underpinning of northern Patagonia. Deformation (Gondwanidian orogeny) associated with the subduction is recognized in both the forearc and the convergent backarc areas. Regional extension, accompanied by bimodal volcanism, began in the Late Triassic and led to the formation of a number of north-northwest trending rift basins in Patagonia, which generally followed the Gondwanidian basement grain. Continued extension in the Jurassic and Early Cretaceous led to the opening of the Rocas Verdes marginal basin in southern Chile and, ultimately, to the opening of the South Atlantic Ocean. Once oceanic crust began to form, faulting and volcanism declined in Patagonia. During the late Early Cretaceous to the Late Cretaceous, sags over the rift basins coalesced to form a broad backarc basin behind the volcanic arc to the west. These sags are suggestive of thermally driven subsidence. Subsidence of the evolving Atlantic margin allowed extensive marine transgressions to take place from the east. The stratigraphic record of northern Patagonia reflects these events. The upper Paleozoic to upper Mesozoic sedimentary sequences were deposited in basins directly associated with convergent activity along the margin of Gondwanaland or in rift basins created during its breakup. Even though the Tertiary evolution of Patagonia was dominated by events along the western margin of South America, the patterns of sediment transport, thickness, and general shoreline position were still influenced by the locations of the Mesozoic rifts formed during the breakup of Gondwanaland.

  16. Oceanography of the Chilean Patagonia

    Science.gov (United States)

    Pantoja, Silvio; Luis Iriarte, José; Daneri, Giovanni

    2011-03-01

    Chilean Patagonia is one of the most extended fjord regions in the world that covers nearly 240,000 km 2 with an extremely complex coastline and topography in one of the least densely populated areas of the country (1-8 inhabitants every 10 km 2). In recent years, the area has been undergoing somewhat intense pressure since several commercial projects in hydroelectricity, tourism, and commercial salmon and mytilid cultures have been developed, or are in progress. Concomitantly, several large research programs have been devised to study the physical, chemical, and biological environment of Patagonia, such as the CIMAR FIORDO, and recently COPAS Sur-Austral based at Universidad de Concepcion, that attempts to close the bridge between oceanographic knowledge and its use by society. In this introductory article we summarize the collection of papers comprising this Special Issue of Continental Shelf Research. These papers deal with aspects of regional oceanography and geology, inorganic and organic geochemistry, ecology of pelagic and benthic organisms, and past changes in productivity.

  17. La salud laboral revisitada : El caso de los trabajadores petroleros de la Patagonia Austral

    OpenAIRE

    Guerra, Lía Gabriela

    2015-01-01

    La presente comunicación surge de un trabajo de investigación en curso, en el marco de una tesis doctoral, relativa al impacto en la salud mental de los trabajadores petroleros de las condiciones laborales propias del sector; dicha indagación se sitúa el Golfo San Jorge, en la Patagonia argentina. Dada la centralidad del trabajo - que más allá de los debates teóricos al respecto, continúa siendo, en la experiencia subjetiva, el organizador de la vida cotidiana –, la indagación de las condi...

  18. CONSANGUINITY BY RANDOM ISONYMY AND SOCIOECONOMIC DEVELOPMENT IN ARGENTINA: A POPULATION STUDY.

    Science.gov (United States)

    Dipierri, José Edgardo; Rodríguez-Larralde, Alvaro; Barrai, Italo; Redomero, Esperanza Gutiérrez; Alonso-Rodríguez, Concepción; Alfaro, Emma Laura

    2017-05-01

    In human populations various flexible, labile and interdependent structures (genetic, demographic, socioeconomic) co-exist, each of which can be organized in an hierarchical order corresponding to administrative entities. The relationship between consanguinity, as estimated by random isonymy (F ST), and socioeconomic conditions was analysed at different levels of political and administrative organization in Argentina. From the surnames of 22,666,139 voters from the 2001 electoral roll, F ST was estimated for 510 Argentinian departments. Using a principal component analysis, a Socio-Demographic and Economic Indicator (SDEI), summarizing the effect of 22 socioeconomic and demographic variables at the departmental level, was computed. The relationship between departmental F ST and SDEI values was analysed for the whole nation and within regions using multiple regression analysis. The F ST presented a clinal distribution with the highest values in the north and west of the country, while SDEI expressed the opposite behaviour. A negative and significant correlation was observed between F ST and SDEI, accounting for 46% of the variation in consanguinity in Argentina. The strongest correlations of F ST with SDEI were observed in the Central, Patagonia and Cuyo regions, i.e. those with the highest values of SDEI and lowest values of F ST.

  19. Late Quaternary stratigraphy, sedimentology, and geochemistry of an underfilled lake basin in the Puna (north-west Argentina)

    Science.gov (United States)

    McGlue, Michael M.; Cohen, Andrew S.; Ellis, Geoffrey S.; Kowler, Andrew L.

    2013-01-01

    Depositional models of ancient lakes in thin-skinned retroarc foreland basins rarely benefit from appropriate Quaternary analogues. To address this, we present new stratigraphic, sedimentological and geochemical analyses of four radiocarbon-dated sediment cores from the Pozuelos Basin (PB; northwest Argentina) that capture the evolution of this low-accommodation Puna basin over the past ca. 43 cal kyr. Strata from the PB are interpreted as accumulations of a highly variable, underfilled lake system represented by lake-plain/littoral, profundal, palustrine, saline lake and playa facies associations. The vertical stacking of facies is asymmetric, with transgressive and thin organic-rich highstand deposits underlying thicker, organic-poor regressive deposits. The major controls on depositional architecture and basin palaeogeography are tectonics and climate. Accommodation space was derived from piggyback basin-forming flexural subsidence and Miocene-Quaternary normal faulting associated with incorporation of the basin into the Andean hinterland. Sediment and water supply was modulated by variability in the South American summer monsoon, and perennial lake deposits correlate in time with several well-known late Pleistocene wet periods on the Altiplano/Puna plateau. Our results shed new light on lake expansion–contraction dynamics in the PB in particular and provide a deeper understanding of Puna basin lakes in general.

  20. The first geological mapof Patagonia El primer mapa geológico de la Patagonia

    OpenAIRE

    Eduardo O. Zappettini; José Mendía

    2009-01-01

    This contribution analyses the first geological mapof Patagonia drawn by Darwin around 1840, and colour-painted by Darwin himself.It had remained unpublished and only a small version in black and white hadbeen printed before. The different units mapped by Darwin are analysed from amodern perspective, and his ability to show a synthesis of the complexgeological structure of Patagonia is stressed.La presente contribución analiza elprimer mapa geológico de la Patagonia realizado por Darwin cerca...

  1. Description of the 5th instar nymph of Oenopiella punctaria (Stål, 1859) Hemiptera: Heteroptera: Pentatomidae), with new distributional records from Southern Patagonia.

    Science.gov (United States)

    Faúndez, Eduardo I; Carvajal, Máriom A

    2016-01-21

    The 5th instar nymph of Oenopiella punctaria (Stål, 1859) is described and illustrated for the first time, together with new distributional records from Patagonia. The new records are from Santa Cruz Province (Argentina), and the Magallanes Region (Chile). The latter is the southernmost record for this species and also for the Carpocorini in South America. In light of the new data, the biogeography of Oenopiella is discussed, and it is concluded that an Andean origin may be possible.

  2. [Does geographic context matter in diabetes-related mortality? Spatial and time trends in Argentina, 1990-2012].

    Science.gov (United States)

    Leveau, Carlos M; Marro, M Jimena; Alonso, Valeria; Lawrynowicz, Alicia E B

    2017-02-13

    The aim of this study was to identify spatial-temporal clusters of high and low diabetes-related mortality from 1990 to 2012 in Argentina. This was a spatial-temporal retrospective ecological study in the population older than 34 years living in Argentina, according to sex, from 1990 to 2012. The spatial units of analysis consisted of the country's departments (subdivisions of the provinces) plus the Autonomous City of Buenos Aires. Spatial-temporal exploration technique was used to detect clusters with high and low mortality. Areas with high mortality from diabetes mellitus were found in the Central-West of the country, and areas with low mortality were found in the coastal region of the province of Buenos Aires and Patagonia. Clusters with high mortality occupied a period from 1995 to 2008; clusters with low mortality shifted towards the years 2002 to 2012. The recent drop in mortality from diabetes was not geographically homogeneous, but displayed a marked decrease in the eastern area of the Province of Buenos Aires and the Autonomous City of Buenos Aires.

  3. Influence of precipitation, landscape and hydrogeomorphic lake features on pelagic allochthonous indicators in two connected ultraoligotrophic lakes of North Patagonia

    Energy Technology Data Exchange (ETDEWEB)

    Queimalinos, Claudia, E-mail: queimalinosc@comahue-conicet.gob.ar [Laboratorio de Fotobiologia, Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA, UNComahue-CONICET), Quintral 1250, R8400FRF Bariloche, Rio Negro (Argentina); Reissig, Mariana; Dieguez, Maria del Carmen [Laboratorio de Fotobiologia, Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA, UNComahue-CONICET), Quintral 1250, R8400FRF Bariloche, Rio Negro (Argentina); Arcagni, Marina; Ribeiro Guevara, Sergio [Laboratorio de Analisis por Activacion Neutronica (LAAN), Centro Atomico Bariloche, Comision Nacional de Energia Atomica, Av. Bustillo 9500, R8402AGP Bariloche, Rio Negro (Argentina); Campbell, Linda [School of Environmental Studies, Saint Mary' s University, 923 Robie Street, Halifax, Nova Scotia, Canada B3H-3C3 (Canada); Soto Cardenas, Carolina [Laboratorio de Fotobiologia, Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA, UNComahue-CONICET), Quintral 1250, R8400FRF Bariloche, Rio Negro (Argentina); Rapacioli, Raul [Facultad de Ingenieria, Universidad Nacional del Comahue, Buenos Aires1400, Q8300IBX Neuquen (Argentina); and others

    2012-06-15

    We investigated the terrestrial influence on two chained deep ultraoligotrophic lakes of North Patagonia (Argentina) through the seasonal analysis of two pelagic allochthonous indicators: i) water color, as a proxy of allochthonous dissolved organic matter in lakes; and ii) the color to chlorophyll a ratio (Color:Chla), as an indicator of the relationship between allochthonous and autochthonous carbon pools. We also evaluated the potential transfer pathways of the allochthonous dissolved organic matter into the pelagic food webs of these deep lakes, including the natural zooplankton {delta}{sup 13}C in the analysis. The dynamics of the allochthonous indicators were related to the precipitation regime, water level fluctuations, and hydrogeomorphic and catchment features of lakes Moreno East and Moreno West. The water color (absorbance at 440 nm) was extremely low (< 0.28 m{sup -1}) in both lakes regardless of the season. However, precipitation and snowmelt regimes drove the increase and decrease of water color, respectively. A significant positive relationship between the zooplankton bulk {delta}{sup 13}C with the water color would suggest an input of allochthonous organic carbon into the pelagic consumers. The incorporation of the dissolved allochthonous material into higher trophic levels is likely favored by the bacterivorous behavior of planktonic organisms, mixotrophic flagellates and ciliates, which dominate the pelagic food webs of these Patagonian lakes. Morphometric aspects, mainly the higher water residence time, led to lower values of allochthony in Moreno East compared to Moreno West, probably accentuated by its upper position in the lake chain. Overall, our results suggest that these allochthonous signals can bring insight into the magnitude of the interaction between terrestrial environments and lake ecosystems, even in extremely clear and ultraoligotrophic systems, such as the Andean Patagonian lakes. - Highlights: Black-Right-Pointing-Pointer Pelagic

  4. Across the southern Andes on fin: glacial refugia, drainage reversals and a secondary contact zone revealed by the phylogeographical signal of Galaxias platei in Patagonia.

    Science.gov (United States)

    Zemlak, Tyler S; Habit, Evelyn M; Walde, Sandra J; Battini, Miguel A; Adams, Emily D M; Ruzzante, Daniel E

    2008-12-01

    We employed DNA sequence variation at two mitochondrial (control region, COI) regions from 212 individuals of Galaxias platei (Pisces, Galaxiidae) collected throughout Patagonia (25 lakes/rivers) to examine how Andean orogeny and the climatic cycles throughout the Quaternary affected the genetic diversity and phylogeography of this species. Phylogenetic analyses revealed four deep genealogical lineages which likely represent the initial division of G. platei into eastern and western lineages by Andean uplift, followed by further subdivision of each lineage into separate glacial refugia by repeated Pleistocene glacial cycles. West of the Andes, refugia were likely restricted to the northern region of Patagonia with small relicts in the south, whereas eastern refugia appear to have been much larger and widespread, consisting of separate northern and southern regions that collectively spanned most of Argentinean Patagonia. The retreat of glacial ice following the last glacial maximum allowed re-colonization of central Chile from nonlocal refugia from the north and east, representing a region of secondary contact between all four glacial lineages. Northwestern glacial relicts likely followed pro-glacial lakes into central Chilean Patagonia, whereas catastrophic changes in drainage direction (Atlantic --> Pacific) for several eastern palaeolakes were the likely avenues for invasions from the east. These mechanisms, combined with evidence for recent, rapid and widespread population growth could explain the extensive contemporary distribution of G. platei throughout Patagonia.

  5. Sweet cherry production in South Patagonia

    NARCIS (Netherlands)

    Cittadini, E.D.; Sanz, C.E.; Pugh, A.B.; Peri, P.L.; Szlápelis, E.; Cárcamo, M.A.; Kikuchi, N.; Manavella, F.A.; San Martino, L.; Ñancucheo, J.A.; Muñoz, M.; Ridder, de N.; Keulen, van H.; Mundet, C.A.

    2008-01-01

    In South Patagonia, the total sweet cherry (Prunus avium L.) area has increased from 176 ha in 1997 to 507 ha in 2004, of which 232 ha are located in Los Antiguos (46°19¿ SL; 220 m elevation), 158 ha in the Lower Valley of Chubut River (LVCHR) (43°16¿ SL; 30 m elevation), 52 ha in Sarmiento (45°35¿

  6. Estado del conocimiento taxonómico de la fauna de Chironomidae (Diptera: Nematocera de la Patagonia Current state of the taxonomic knowledge of the Chironomidae fauna (Diptera: Nematocera from Patagonia

    Directory of Open Access Journals (Sweden)

    Mariano Donato

    2009-06-01

    Full Text Available La familia Chironomidae (Diptera: Nematocera es uno de los grupos de insectos más ampliamente distribuidos y abundantes en cuerpos de agua dulce. Los representantes de esta familia pueden explotar áreas con amplios gradientes ambientales. La información que se presenta está basada en la recopilación de datos distribucionales bibliográficos, del estudio del material tipo de las especies de Chironomidae depositadas en el Natural History Museum (UK y del material de colección del Museo de La Plata (Argentina. En la Patagonia, se registran 9 subfamilias, la subfamilia monotípica Chilenomyiinae es endémica de esta área. Dentro de estas subfamilias, 53 de los 111 géneros conocidos para América del Sur están presentes en la Patagonia. Del total de géneros de la Patagonia, el 20 % es endémico y 7 de ellos muestran relaciones transantárticas. En la Patagonia, se registran 177 especies de Chironomidae, el 98% de éstas son endémicas, el 3 % son consideradas nomina dubia y el 17% requiere revisión ya que su ubicación sistemática es dudosa. Las descripciones originales de las especies patagónicas de Chironomidae están basadas principalmente sobre machos (n=58 y machos y hembras (n=43, ambas representan el 57% del total; el resto de las especies han sido descriptas con diferentes combinaciones de estadios del ciclo de desarrollo.The Chironomidae (Diptera: Nematocera family is one of the most widely distributed group of insects and often the most abundant in freshwater environments. Representatives of this family can exploit a wide range of environmental gradients. The information here presented is based on the compilation of distributional data obtained from bibliography, the study of the type material deposited in the Natural History Museum (UK and the collection material from Museo de La Plata (Argentina. Nine subfamilies are recorded from Patagonia, being the monotypic subfamily Chilenomyiinae endemic for the area. From the 111 known

  7. Detection of the mosquito-borne flaviviruses, West Nile, Dengue, Saint Louis Encephalitis, Ilheus, Bussuquara, and Yellow Fever in free-ranging black howlers (Alouatta caraya) of Northeastern Argentina.

    Science.gov (United States)

    Morales, María A; Fabbri, Cintia M; Zunino, Gabriel E; Kowalewski, Martín M; Luppo, Victoria C; Enría, Delia A; Levis, Silvana C; Calderón, Gladys E

    2017-02-01

    Several medically important mosquito-borne flaviviruses have been detected in Argentina in recent years: Dengue (DENV), St. Louis encephalitis (SLEV), West Nile (WNV) and Yellow Fever (YFV) viruses. Evidence of Bussuquara virus (BSQV) and Ilheus virus (ILHV) activity were found, but they have not been associated with human disease. Non-human primates can act as important hosts in the natural cycle of flaviviruses and serological studies can lead to improved understanding of virus circulation dynamics and host susceptibility. From July-August 2010, we conducted serological and molecular surveys in free-ranging black howlers (Alouatta caraya) captured in northeastern Argentina. We used 90% plaque-reduction neutralization tests (PRNT90) to analyze 108 serum samples for antibodies to WNV, SLEV, YFV, DENV (serotypes 1and 3), ILHV, and BSQV. Virus genome detection was performed using generic reverse transcription (RT)-nested PCR to identify flaviviruses in 51 antibody-negative animals. Seventy animals had antibodies for one or more flaviviruses for a total antibody prevalence of 64.8% (70/108). Monotypic (13/70, 19%) and heterotypic (27/70, 39%) patterns were differentiated. Specific neutralizing antibodies against WNV, SLEV, DENV-1, DENV-3, ILHV, and BSQV were found. Unexpectedly, the highest flavivirus antibody prevalence detected was to WNV with 9 (8.33%) monotypic responses. All samples tested by (RT)-nested PCR were negative for viral genome. This is the first detection of WNV-specific antibodies in black howlers from Argentina and the first report in free-ranging non-human primates from Latin-American countries. Given that no animals had specific neutralizing antibodies to YFV, our results suggest that the study population remains susceptible to YFV. Monitoring of these agents should be strengthened to detect the establishment of sylvatic cycles of flaviviruses in America and evaluate risks to wildlife and human health.

  8. Detection of the mosquito-borne flaviviruses, West Nile, Dengue, Saint Louis Encephalitis, Ilheus, Bussuquara, and Yellow Fever in free-ranging black howlers (Alouatta caraya of Northeastern Argentina.

    Directory of Open Access Journals (Sweden)

    María A Morales

    2017-02-01

    Full Text Available Several medically important mosquito-borne flaviviruses have been detected in Argentina in recent years: Dengue (DENV, St. Louis encephalitis (SLEV, West Nile (WNV and Yellow Fever (YFV viruses. Evidence of Bussuquara virus (BSQV and Ilheus virus (ILHV activity were found, but they have not been associated with human disease. Non-human primates can act as important hosts in the natural cycle of flaviviruses and serological studies can lead to improved understanding of virus circulation dynamics and host susceptibility. From July-August 2010, we conducted serological and molecular surveys in free-ranging black howlers (Alouatta caraya captured in northeastern Argentina. We used 90% plaque-reduction neutralization tests (PRNT90 to analyze 108 serum samples for antibodies to WNV, SLEV, YFV, DENV (serotypes 1and 3, ILHV, and BSQV. Virus genome detection was performed using generic reverse transcription (RT-nested PCR to identify flaviviruses in 51 antibody-negative animals. Seventy animals had antibodies for one or more flaviviruses for a total antibody prevalence of 64.8% (70/108. Monotypic (13/70, 19% and heterotypic (27/70, 39% patterns were differentiated. Specific neutralizing antibodies against WNV, SLEV, DENV-1, DENV-3, ILHV, and BSQV were found. Unexpectedly, the highest flavivirus antibody prevalence detected was to WNV with 9 (8.33% monotypic responses. All samples tested by (RT-nested PCR were negative for viral genome. This is the first detection of WNV-specific antibodies in black howlers from Argentina and the first report in free-ranging non-human primates from Latin-American countries. Given that no animals had specific neutralizing antibodies to YFV, our results suggest that the study population remains susceptible to YFV. Monitoring of these agents should be strengthened to detect the establishment of sylvatic cycles of flaviviruses in America and evaluate risks to wildlife and human health.

  9. Wildland-Urban Interface Fires and Socioeconomic Conditions: A Case Study of a Northwestern Patagonia City

    Science.gov (United States)

    de Torres Curth, Monica; Biscayart, Carolina; Ghermandi, Luciana; Pfister, Gabriela

    2012-04-01

    In many regions of the world, fires are primarily of anthropogenic origin. In northwestern Patagonia, the number of fires is not correlated with meteorological variables, but is concentrated in urban areas. This study was conducted in the wildland-urban interface (WUI) area of San Carlos de Bariloche (Patagonia, Argentina), within the Nahuel Huapi National Park. WUI fires are particularly problematic because, besides people and goods, they represent a danger to protected areas. We studied the relationship between fire records and socioeconomic indicators within the WUI of San Carlos de Bariloche. We conducted a Multiple Correspondence Factorial Analysis and an Ascendant Hierarchical Classification of the city neighborhoods. The results show that the neighborhoods in Bariloche can be divided into three classes: High Socioeconomic Fire Risk neighborhoods, including neighborhoods with the highest fire rates, where people have low instruction level, high levels of unsatisfied basic needs and high unemployment levels; Low Socioeconomic Fire Risk neighborhoods, that groups neighborhoods which present the opposite characterization, and Moderate Socioeconomic Fire Risk neighborhoods, which are more heterogeneous. Once neighborhoods were classified, a Socioeconomic Fire Risk map was generated, supplementing the existing WUI Fire Danger map. Our results emphasize the relevance of socioeconomic variables to fire policies.

  10. Estado del conocimiento taxonómico de la fauna de Chironomidae (Diptera: Nematocera de la Patagonia

    Directory of Open Access Journals (Sweden)

    Mariano DONATO

    2009-01-01

    Full Text Available La familia Chironomidae (Diptera: Nematocera es uno de los grupos de insectos más ampliamente distribuidos y abundantes en cuerpos de agua dulce. Los representantes de esta familia pueden explotar áreas con amplios gradientes ambientales. La información que se presenta está basada en la recopilación de datos distribucionales bibliográficos, del estudio del material tipo de las especies de Chironomidae depositadas en el Natural History Museum (UK y del material de colección del Museo de La Plata (Argentina. En la Patagonia, se registran 9 subfamilias, la subfamilia monotípica Chilenomyiinae es endémica de esta área. Dentro de estas subfamilias, 53 de los 111 géneros conocidos para América del Sur están presentes en la Patagonia. Del total de géneros de la Patagonia, el 20 % es endémico y 7 de ellos muestran relaciones transantárticas. En la Patagonia, se registran 177 especies de Chironomidae, el 98% de éstas son endémicas, el 3 % son consideradas nomina dubia y el 17% requiere revisión ya que su ubicación sistemática es dudosa. Las descripciones originales de las especies patagónicas de Chironomidae están basadas principalmente sobre machos (n=58 y machos y hembras (n=43, ambas representan el 57% del total; el resto de las especies han sido descriptas con diferentes combinaciones de estadios del ciclo de desarrollo.

  11. LA PATAGONIA ORIENTAL SEGÚN UNA REAL CÉDULA de 1570 MENOSPRECIADA POR LA HISTORIOGRAFÍA CHILENA

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    MANUEL RAVEST MORA

    2005-12-01

    Full Text Available Versa este trabajo sobre la Real Cédula de Felipe II que, en 1570, fusionó parte de la Patagonia Oriental con la Provincia del Río de la Plata, origen de la República Argentina, donde, al parecer, supieron del documento treinta años después de finalizado el debate con Chile acerca de los derechos al extremo meridional de América. Descubierta por un diplomático chileno, que informó de ella a su Cancillería en 1876 y la mencionó en un libro publicado en 1903, ha sido sistemáticamente ignorada por los escritores chilenos. Examina este trabajo las posibles causas de ese silencio historiográfico, como también las rectificaciones que la RC introduce en la tesis clásica o fundacional de Chile, formulada a mediados del XIX por Miguel Luis Amunátegui, según la cual ese país siempre ejerció jurisdicción sobre la totalidad de la Patagonia Oriental desde 1554This work deals with a 1570 Phillip the II Decree that fused a section of Atlantic Patagonia with the Rio de la Plata Province, origin of late Argentine Republic, who, apparently, learned about it thirty years after ended the discussion held with Chile in respect the rights of each country towards the southern extreme of America. Found by a chilean diplomat, who informed his Ministry of Foreign Affairs in 1876 and wrote about the document in a book published in 1903, it has been systematically ignored by chilean scholars. The work examines the possible causes for this historiographyc silence, and the rectifications that the Royal Decree introduces in the classical chilean thesis about Patagonia, enounced by Miguel Luis Amunategui in middle XIX century, according to which that whole territory always belonged to Chile since 1554

  12. Aclerdidae (Hemiptera: Coccoidea de la Argentina Aclerdidae (Hemiptera: Coccoidea from Argentina

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    María Cristina Granara de Willink

    2004-12-01

    Full Text Available Se describen e ilustran la hembra adulta, el primer estadio y un estadio intermedio de la hembra de Aclerda colihuensis sp. nov., encontrada sobre Chusquea culeou una Bambusaceae, de los bosques andinopatagónicos. Se brinda una clave para las especies de Aclerda Signoret, de la región Neotropical. Se cita esta familia por primera vez para la Argentina.The female, the first stage, and intermediate female stages of Aclerda colihuensis n. sp., are described and illustrated. A key to the neotropical species for Aclerda Signoret is given. This is the first family report from Argentina. The new species was found on Chusquea culeou Desv. Bambusaceae, from the Patagonia forest.

  13. Acciones bloqueantes alrededor de los setenta grados oeste en el sur de Sudamérica Blocking action arround seventy degrees West in the South of South America

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    Adelia P. Alessandro

    2005-12-01

    esta situación. La presencia de estos sistemas y la falta de viento N o NE inciden en la extremadamente escasa precipitación recibida en el Noreste de la Argentina, en las altas temperaturas en la Patagonia y bajas temperaturas en el NE y centro del país.Blocking situations near 70ºW south of South America are characterised. Cases which initiate to the west and those to the east of the above- mentioned longitude are distinguished. Averaging all cases it is seen that the Atlantic high as well as the Pacific high is displaced to the south for the first and second group respectively. Four different models result from the Principal Component Analysis, three of which representing blocking situations over the south-eastern Pacific Ocean and one of the south-western Atlantic. The trajectory of those highs that commence to the west have a cuasi zonal orientation with a speed of 20 Km/h, meanwhile those that region to the east have a slight component to the north with a speed of 20.5 Km/h. The mean centre of the anticyclones has a geopotential height of 227.7 gpm. The associated temperature anomalies are negative over most of Argentina, excepting the extreme south and the northeast, for both groups. When the blocking high is to the west of 70ºW the anomalies are more negative over Patagonia and more positive over the north-eastern country. Precipitations in Patagonia are superior with blockings beginning to the east of 70ºW with respect to those that first appear to the west, with exception of Ushuaia (54.48ºS, 68.19ºO station and north-eastern Argentina. The situation of February 2004 is described. This month has been selected because has an extreme low zonal circulation index, a high meridional index and a very high blocking index I with respect to southern summer, showing in the study area the presence of several blocking systems to the south of South America. These systems are associated with a lack of N and NE winds giving extremely low precipitations over north

  14. Childhood cancer in Argentina: Survival 2000-2007.

    Science.gov (United States)

    Moreno, Florencia; Florencia, Moreno; Dussel, Veronica; Veronica, Dussel; Orellana, Liliana; Liliana, Orellana

    2015-08-01

    Information on the epidemiology of childhood cancer in Latin America is limited. The Argentinean Oncopaediatric Registry (ROHA) is a population-based registry active since 2000. This paper describes the 3-year survival experience of children diagnosed with cancer in Argentina during 2000-2007 by major morphological subgroup, age, sex, and geographical region of residence. Newly diagnosed paediatric cancer cases are registered in ROHA (estimated coverage is 93% of the country's cases). Three-year overall survival was estimated using Kaplan-Meier methods. Univariate Cox models were used to compare subgroup survival. Between 2000 and 2007, a total of 10,181 new cancer diagnoses in children aged 0-14 years were reported to the registry. Three-year overall survival (95%CI) for all cancers was 61.7% (60.7; 62.7). Specific survival for the most frequent morphological types was: leukaemias 63.3% (61.6; 64.9), lymphomas and related neoplasms 75.3% (72.7; 77.7), brain neoplasms 46.3% (43.9; 48.7), soft-tissue sarcomas 52.3% (48.0; 56.5), neuroblastomas 49.6% (44.6; 54.3), renal tumours 76.7% (72.2; 80.6), and malignant bone tumours 47.2% (42.3; 51.9). Overall survival was associated with age but not sex and varied by geographical region. Compared to other regions, patients who resided in the capital city had a significantly higher survival: 69.6% (65.8; 73.0) versus 63.5% (59.4; 67.4) in Patagonia, 63.2% (61.9; 64.5) in the central region, 58.0% (54.2; 61.7) in Cuyo, 55.6% (52.5; 58.6) in the north-east, and 55.4% (52.4; 58.2) in the north-west (all P values <0.005). Of children diagnosed with cancer in Argentina, 62% survived at least 3 years after diagnosis. Even though this figure is lower than that reported for more developed countries, survival patterns by diagnosis, age and sex were quite similar. Survival was lower in the two northern regions, which are areas with higher poverty levels. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Freshwater fishes of Patagonia: conservation and fisheries.

    Science.gov (United States)

    Cussac, V E; Habit, E; Ciancio, J; Battini, M A; Riva Rossi, C; Barriga, J P; Baigún, C; Crichigno, S

    2016-07-01

    The absence of much literature on the Patagonian fish fauna in comparison with that of the neotropics, has previously been blamed on its poor species diversity. Knowledge of the fishes of Patagonia, however, rose sharply at the beginning of the present century, allowing for an understanding of the complex biogeographical history that has led to the present diversity and distribution patterns. There are several new and potential threats to biodiversity and conservation of Patagonian fishes, such as the introduction of exotic species, damming, climate change and changes geared to safeguard economic interests, often acting synergistically. A great amount of new information is now available and the aim of the present review is to articulate this knowledge in a comprehensive way in order to aid in the development of tools to face the increasing challenges posed by environmental change and human activity. Knowledge about fishes of Patagonia has grown at the same time as human actions, and presence. © 2016 The Fisheries Society of the British Isles.

  16. Registro fósil y distribución de Anadenathera en Argentina desde el Mioceno hasta la actualidad

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    Fernández-Pacella, L.

    2015-06-01

    Full Text Available Currently Fabaceae, is one of the dominant families of the Seasonally Dry Tropical Forests or Neotropical seasonal dry forests. Anadenanthera which integrates the family, has wide geographical distribution in South America and the West Indies, but in Argentina it`s only present Anadenantera colubrina var. cebil in the north and their records are represented from the Miocene to the present through palynomorphs and mineralized woods. The main objective of this work is to contribute to the understanding in the context of the history of Anadenanthera during the Neogene and Quaternary in Argentina, on the basis of the review and integration of the paleobotanical history, geological and climatic available that have affected the genre in the country. Studied fossil materials come from different geological formations of Argentina: Chenque Formation (Miocene, Paraná Formation (Middle Miocene, San José Formation (Middle Miocene, Ituzaingó Formation (Pliocene and Iberá (Holocene. The material found on the Chenque Formation is referred to Polyadopollenites coincides with the described material for the Middle Miocene of the central-eastern Argentina and the Pliocene of northeast Argentina. On the other hand in Paraná and Ituzaingó Formation studied sample of mineralized woods of Anadenantheroxylon villaurquisense, finally the sample found in Holocene of Iberá Corrientes Province corresponds to Anadenanthera colubrina var. macrocarpa. With these data it can be concluded that Anadenathera had a wide geographical record in Miocene and Holocene of Argentina, it was found in sediments from the lower Miocene of Patagonia by integrating a Subtropical Paleoflora. From the Middle-Upper Miocene integrated the vegetation in northeast Argentine constituting xerophiles forests. Their last record is equivalent to the Middle Holocene of sediments from Ibera integrating the regional vegetation and indicating an open vegetation characteristics of dry environments

  17. Primer registro de Naupactus ruizi (Coleoptera: Curculionoidea asociado con Pinus ponderosa (Gymnospermae: Pinaceae en Patagonia

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    Cecilia A. GOMEZ

    2006-01-01

    Full Text Available Naupactus ruizi (Brèthes es un gorgojo de rostro corto, distribuido en la Argentina y Chile, que habita en ambientes áridos asociado con vegetación xerofítica y alcanza el rango más austral entre los miembros de la tribu Naupactini. Un relevamiento de insectos y de patógenos como plagas potenciales, realizado durante el 2005 en plantaciones de Pinus spp. en la Patagonia andina argentina, resultó en el hallazgo de adultos de N. ruizi que se alimentaban de acículas de Pinus ponderosa Dougl. ex Laws. Este hallazgo es sorprendente dado que las especies de Naupactini, consumen casi exclusivamente angiospermas. Interpretamos que el cambio de huésped, habría ocurrido como consecuencia de una colonización reciente favorecida por la amplia distribución geográfica del gorgojo y su capacidad para sobrevivir en hábitats marginales, donde probablemente las plantas nativas son escasas y el nuevo huésped presenta una gran abundancia local.

  18. Disponibilidad de rocas y costos de aprovisionamiento en el extremo austral de Patagonia meridional : integración de resultados en una escala regional

    OpenAIRE

    Charlin, Judith; Pallo, Cecilia

    2017-01-01

    Nuestro trabajo en el sur de Patagonia meridional estuvo orientado al estudio de la disponibilidad de rocas para la manufactura de artefactos con el objetivo de evaluar las estrategias de aprovisionamiento y explotación de las materias primas líticas implementadas por los grupos humanos durante el Holoceno tardío. Nuestro foco de trabajo ha sido el campo volcánico Pali Aike (CVPA, Santa Cruz, Argentina) y áreas vecinas, sumando un total de 84 fuentes po...

  19. Trace elements deposition in the Tierra del Fuego region (south Patagonia) by using lichen transplants after the Puyehue-Cordón Caulle (north Patagonia) volcanic eruption in 2011.

    Science.gov (United States)

    Conti, Marcelo Enrique; Jasan, Raquel; Finoia, Maria Grazia; Iavicoli, Ivo; Plá, Rita

    2016-04-01

    Lichen Usnea barbata transplants were tested as a biomonitor of atmospheric deposition in an apparently pristine environment that is Tierra del Fuego region (Patagonia, Argentina). The present survey is connected with the volcanic eruption that started in north Patagonia on June 4, 2011 from the Puyehue-Cordón Caulle volcano, Chile (north Patagonia, at 1700 km of distance of our sampling sites). Lichens were collected in September 2011 (one month of exposure) and September 2012 (1 year of exposure) in 27 sites covering the northern region of the province where trees are not present. The atmospheric deposition of 27 elements by using Neutron Activation Analysis (NAA) was determined in the collected samples. The first aim of the study was to evaluate the influence of the volcanic eruption on the regional atmospheric deposition comparing our results with baseline data we determined in U. barbata in 2006 in the same sites. The second aim was to test possible patterns of bioaccumulation between the two sampling campaigns after the volcanic eruption. With respect to 2006 baseline levels, we found significant higher levels for As, Ba, Co, Cr, Cs, Na, Sb and U in lichens collected after 1 month of exposure (first sampling campaign--2011). Between the two sampling campaigns (2011-2012) after the eruption, lichens reflected the natural contamination by volcanic ashes with significantly higher median levels of Br, Cr, Fe, K, Na, Sc, and Se. Results confirmed the very good aptitude of U. barbata to reflect the levels of elements in the environment at global scale and to reflect the volcanic emissions at distant places. Volcanic eruptions cause the emission in the atmosphere of elevated levels of particulate matter. In this regard, our findings demonstrate the importance to evaluate the metal composition of the particles to avoid possible health effects.

  20. Fabiana imbricata shurblands: natural firebreaks in the northwestern Patagonia?

    Science.gov (United States)

    Ghermandi, L.; Dudinszky, N.; Oddi, F. J.

    2009-04-01

    Fire is a natural disturbance that affects different ecosystems like the Northwestern Patagonian woodland/steppe ecotone. Here, the fire impact on the vegetation depends on the heterogeneity of the plant communities and the environment. This includes different responses and adaptations to fire of the species present in this community. Fabiana imbricata is a shrub characteristic of Patagonian grasslands and although its response to fire is not well known, it generate a special landscape pattern. Direct field observation coupled with aerial photography interpretation and remote sensing data were used to identify the vegetation pattern. From the lower to upper zones of the hillside topographic gradient, the vegetation changes from grasslands to F. imbricata shrublands, followed by open Austrocedrus chilensis woodland and ending in rock outcrop. We hypothesized that F. imbricata acts as a firebreak that creates an Austocedrus chilensis refuge in the upper part of the topographic gradient. This fire line could relate to horizontal fuel discontinuity that derives from the presence of bare soil that occurs within the F. imbricata shrubs. If fires are not very intense, the fuel discontinuity would stop the spread of fire coming from the grassland. In this survey we worked in one of the post-fire sites of San Ramón ranch (41° 03´19´´S and 71°01´50´´W), 30 km east of Bariloche, Patagonia, Argentina, where we observed the above described pattern. For this site, we know of two fire events, and the oldest occurred 36 years ago, and the second occurred 10 years ago. We also have data regarding the F. imbricata shrubland dynamics. Dendrochronology techniques were used to determine the age of the shrubland. We match this data with Landsat TM images coupled with aerial photography interpretation to determine the pre and post- fire vegetation. Future studies analysing other sites where this pattern is present will be needed to corroborate the relationship between the

  1. The chronology of the Last Glacial Maximum and deglacial events in central Argentine Patagonia

    Science.gov (United States)

    Hein, Andrew S.; Hulton, Nicholas R. J.; Dunai, Tibor J.; Sugden, David E.; Kaplan, Michael R.; Xu, Sheng

    2010-05-01

    This paper evaluates the chronology of the last glacial cycle and deglaciation in the Lago Pueyrredón valley of central Patagonia, 47.5° S, Argentina. The valley was a major outlet of the former Patagonian Ice Sheet and the moraines that record its fluctuations are an important proxy record of climate change in southern South America. Such moraines are well-preserved in the Lago Pueyrredón valley owing in part to the semi-arid environment east of the mountain front. Here, we provide the first direct chronology for the age of the "Rio Blanco" moraine system by utilizing cosmogenic-nuclide surface exposure ages. Boulders on the moraines give 10Be exposure ages that indicate the Last Glacial Maximum (LGM) maximum extent occurred by 27-25 ka. Subsequent advances occurred at 23-22 ka, 20-18 ka, and ca. 18-17 ka. Initial deglaciation began after ca. 18-17 ka and was interrupted as evidenced by the Lago Columna moraines up-valley. Subsequently the outlet glaciers occupying both the Lago Pueyrredón basin (Chilean name: Lago Cochrane) and the Lago Buenos Aires basin (Chilean name: Lago General Carrera) to the north, rapidly retreated more than 80 km at around 16.5-15 ka. The timing of the LGM maximum extent and the onset of deglaciation occurred broadly synchronously throughout Patagonia. Deglaciation resulted in a series of interconnected glacier-dammed lakes in the region that initially drained toward the Atlantic Ocean and later drained to the Pacific Ocean as a consequence of disintegrating ice in the Andes.

  2. Cultural Transmission of Traditional Knowledge in two populations of North-western Patagonia

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    Lozada Mariana

    2008-12-01

    Full Text Available Abstract Background In the present study we have investigated the cultural transmission of two types of traditional plant knowledge in two communities of North-western Patagonia, Argentina. In the Pilcaniyeu community, we studied the transmission of traditional knowledge related to horticultural practices in home-gardens, greenhouses and gardens; while in the community of Cuyin Manzano, we studied wild plant gathering customs. Methods Ethnobotanical fieldwork was conducted by means of semi-structured interviews, in which we investigated which plants are used, at what life history phase was learned, modes of transmission and who the principal transmitters were in childhood and adulthood. In both communities, each of this three aspects related to cultural transmission were categorized and the frequencies of each category were obtained. The total number of species recorded in each community was also calculated. Frequencies were analyzed with the Chi-square test of independence. Results and discussion In both communities, transmission of traditional plant knowledge begins at an early age, as a family custom, in which women play a predominant role. Wild plant use and horticultural knowledge continue to be learned during adulthood. This was particularly registered associated with horticultural learning, which receives greater influence from extension agents who are introducing new practices and technology. This outside influence, which implies novelty, could imply syncretism but also traditional knowledge loss. Conclusion Given the remarkable acculturation processes occurring at present in rural communities of Northwestern Patagonia, it might be of vital importance to document traditional knowledge of ancient practices. Moreover, it could be interesting to share our results with both populations in order to encourage participatory activities within the communities which could enhance traditional knowledge horizontal transmission, particularly among

  3. Primeros registros de ácaros oribátidos (Acari: Oribatida de bosques de Nothofagus pumilio en la región Patagónica, Chubut, Argentina

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    Erica V. RUIZ

    2015-01-01

    Full Text Available Se informan diecinueve primeros registros de ácaros oribátidos en suelos de bosques de lenga de la provincia de Chubut, Patagonia argentina. Los mismos pertenecen a los géneros Loftacarus, Liochthonius, Sellnickochthonius, Trichthonius, Austrocarabodes, Maculobates, Tectocepheus, Austroppia, Brachioppiella, Pletzenoppia, Globoppia, Lanceoppia, Membranoppia, Graptoppia, Oppiella, Neoameroppia, Subiasella, Suctobelbella y Pheroliodes. Las especies Suctobelbella pseudomatissima y Pheroliodes roblensis se mencionan por primera vez de la Argentina.

  4. Argentina; Argentine

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-04-01

    This economical study summarizes the energy situation of Argentina: energy institutions and policy, energy companies (oil, electricity, gas, coal), energy supplies (resources, power production, petroleum, natural gas), prices and tariffs, consumption, economical stakes and perspectives (investments, agreements, projects). Energy data for the 1971-1999 period are summarized in graphs and tables. (J.S.)

  5. Patagonia, de margen exótico a periferia turística. Una mirada sobre un área natural protegida de frontera

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    Paula Gabriela Núñez

    2012-01-01

    Full Text Available During the first half of the twentieth century, National Parks in Argentina were located in peripheral border spaces. This configuration responded to previous territorial organization logics developed in the country. In order to analyze the impact and influence of these Natural Protected Areas, the Nahuel Huapi National Park (Andean Patagonia, Argentina case study was considered. It was concluded that, in the region of the Nahuel Huapi, the centralization in the national territorial administration was consolidated through the institutionalization of a Natural Protected Area. Moreover, this process allowed the identification of different approaches from which local planning development and tourism were thought over time, affecting the way Natural Protected Areas were conceived.

  6. Glaciers in Patagonia: Controversy and prospects

    Science.gov (United States)

    Kargel, J. S.; Alho, P.; Buytaert, W.; Célleri, R.; Cogley, J. G.; Dussaillant, A.; Guido, Z.; Haeberli, W.; Harrison, S.; Leonard, G.; Maxwell, A.; Meier, C.; Poveda, G.; Reid, B.; Reynolds, J.; Rodríguez, C. A. Portocarrero; Romero, H.; Schneider, J.

    2012-05-01

    Lately, glaciers have been subjects of unceasing controversy. Current debate about planned hydroelectric facilities—a US7- to 10-billion megaproject—in a pristine glacierized area of Patagonia, Chile [Romero Toledo et al., 2009; Vince, 2010], has raised anew the matter of how glaciologists and global change experts can contribute their knowledge to civic debates on important issues. There has been greater respect for science in this controversy than in some previous debates over projects that pertain to glaciers, although valid economic motivations again could trump science and drive a solution to the energy supply problem before the associated safety and environmental problems are understood. The connection between glaciers and climate change—both anthropogenic and natural—is fundamental to glaciology and to glaciers' practical importance for water and hydropower resources, agriculture, tourism, mining, natural hazards, ecosystem conservation, and sea level [Buytaert et al., 2010; Glasser et al., 2011]. The conflict between conservation and development can be sharper in glacierized regions than almost anywhere else. Glaciers occur in spectacular natural landscapes, but they also supply prodigious exploitable meltwater.

  7. Panorama de la familia Asteraceae (= Compositae en la Republica Argentina An overview of the plant family Asteraceae ( = Compositae in Argentina

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    Liliana Katinas

    2007-07-01

    Full Text Available Se presenta un panorama de la familia Asteraceae en la República Argentina , que incluye una breve historia taxonómica, datos numéricos de tribus, géneros y especies, ejemplos de endemismos y daptaciones ecológicas y una reseña sobre la hipótesis del origen de la familia en Patagonia. En la Argentina, las asteráceas representan la familia más numerosa con 227 géneros (cinco son endémicos y ca. 1400 especies (92 son adventicias y 382 son endémicas. En términos de taxones nativos, se hallan representadas en nuestro país todas las tribus de Asteraceae excepto Inuleae (sensu Bremer. Las tribus Arctoteae y Calenduleae están representadas por taxones adventicios exclusivamente y Cardueae posee sólo una especie nativa. Barnadesieae y Mutisieae son las únicas tribus con géneros endémicos de Argentina y también presentan el porcentaje más alto de géneros y especies en el país en comparación con el resto de las tribus. El mayor número de especies nativas, endémicas y no endémicas, se da en las provincias fitogeográficas Altoandina y Patagónica. La tribu más representada en número de géneros es Heliantheae, y en número de especies nativas es Senecioneae.An overview of the family Asteraceae in Argentina that includes a brief taxonomic history, numerical data of tribes, genera and species, examples of endemisms and ecological adaptations, and a discussion on the hypothesis on the origin of the family in Patagonia is given. Asteraceae is the most numerous family in Argentina , with 227 genera (five are endemic and ca. 1400 species (92 are adventitious and 382 are endemic. In relation to the native taxa, all tribes of Asteraceae occur in Argentina excepting Inuleae (sensu Bremer. Tribes Arctoteae and Calenduleae are represented exclusively by adventitious taxa, and Cardueae has only one native species. Barnadesieae and Mutisieae are the only tribes with endemic genera in Argentina and they also present the highest percentage of

  8. Difilobotriosis humana: Un caso en área no endémica de la Argentina Human diphyllobothriosis: A case in a non-endemic area of Argentina

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    Diego E. Cargnelutti

    2012-02-01

    Full Text Available La difilobotriosis es una parasitosis intestinal causada por la infección de cestodos del genero Diphyllobothrium. En la Argentina, la Patagonia Andina es considerada una zona endémica para esta parasitosis. La infección por Diphyllobothrium latum no ha sido previamente notificada en la provincia de Mendoza; en este trabajo comunicamos un caso de esta parasitosis que fue confirmada por el análisis de las características morfológicas de los huevos eliminados con la materia fecal de un paciente infectado. Se destaca la necesidad de información y capacitación de los profesionales de la salud en el diagnóstico y tratamiento de parasitosis no endémicas.Diphyllobothriosis is an intestinal parasitosis caused by cestodes infection of the genus Diphyllobothrium. In Argentina, the Andean Patagonia is considered an endemic area for this parasitosis. Diphyllobothrium latum infection has not been previously reported in the province of Mendoza, Argentina. We are now reporting then the first case. Diphyllobothriosis was confirmed by examination of morphologic characteristics of the eggs eliminated in the patients' feces. These results suggest the requirement of a more specific training of health workers in the diagnosis and treatment of non endemic parasitosis. We want to emphasize the need of health workers' education on diagnosis and treatment of endemic and non-endemic parasitosis.

  9. Tectonic evolution of Western Patagonia and hydrocarbon habitats

    Energy Technology Data Exchange (ETDEWEB)

    Urien, C.M. (Urien Associates, Buenos Aires (Argentina))

    1993-02-01

    In Devonian times, Western Patagonia was a Pericratonic Foreland basin. The rift-like, faulted platform underwent several marine transgressions-regressions related to tectonic episodes occurring mainly from Hercynian to Andean (Pyrenaic) times that modified the extension and nature of sedimentation in the region, due to the evolution of the Pacific Plate and Margin, and the accretion of successive acidic magmatic arcs. The marine sequences that flooded Patagonia, uneven in extension, shifted from North to South in accordance with differential subsidence in this margin, particularly in the three main sedimentary embayments: Neuquen, San Jorge and Magellan-Malvinas. Transversal ridges, following ancestral transtensional features, rejuvenated during the Atlantic opening separate these embayments. Marine sequences evolved into restricted circulation oxygen poor seas, whose organic matter rich sediments originated hydrocarbon source rocks, identified in the three most important basinal complexes of Patagonia. The beginning of the Andean Orogeny and the emplacement of the Andean Batholith, hindered the Pacific marine presence in western Patagonian basins. Subsequently, an Eastern elongated region-wide subsidence allowed the accumulation of molasse-like sequences over most foredeep sediments in the region, creating several hydrocarbons habitats grouped as follows: Neuquen: Proven: Liassic-Aptian; Potential: Triassic; San Jorge: Proven: U. Jurassic-L. Cretaceous; Unproven: L. Paleozoic-L. Jurassic; Magellan/Malvinas: Proven: L. Cretaceous; Unproven: Jurassic-U. Cretaceous During Laramic time, Atlantic highstand sea levels flooded a great part of Extra Andean Patagonia, while the Andean Chain started rising with an active magmatic arc.

  10. Gamma irradiation as a phytosanitary treatment for fresh pome fruits produced in Patagonia

    Energy Technology Data Exchange (ETDEWEB)

    Perez, J.; Lires, C.; Horak, C.; Pawlak, E.; Docters, A. [Comision Nacional de Energia Atomica, Centro Atomico Ezeiza Presbitero Juan Gonzalez y Aragon No. 15, (B1802AYA) Ezeiza, Buenos Aires (Argentina); Kairiyama, E. [Comision Nacional de Energia Atomica, Centro Atomico Ezeiza Presbitero Juan Gonzalez y Aragon No. 15, (B1802AYA) Ezeiza, Buenos Aires (Argentina)], E-mail: kairiyam@cae.cnea.gov.ar

    2009-07-15

    Argentina produces 1.8 million tons/year of apples (Malus domestica L.) and pears (Pyrus communis L.) in the Patagonia region. Cydia pomonella, codling moth, and Grapholita molesta, Oriental fruit moth, (Lepidoptera: Tortricidae) are quarantine pests in pome fruits. Irradiation is a promising phytosanitary treatment because a dose of 200 Gy completely prevents pest adult emergence. A pilot irradiation process of commercially packaged 'Red Delicious' apples and 'Packham's Triumph' pears was performed in an irradiation facility with a Cobalt 60 source. Quality analyses were carried out at 0, 2, 4, 6 and 8 months of storage (1 deg. C, RH 99%) to evaluate fruit tolerance at 200, 400 and 800 Gy. Irradiation at 200 and 400 Gy had no undesirable effects on fruit quality (pulp firmness, external colour, soluble solids content (SSC), titratable acidity (TA) and sensory evaluations). Irradiation of 'Red Delicious' apples and 'Packham's Triumph' pears can be applied as a commercial quarantine treatment with a minimum absorbed dose of 200 Gy (to control codling moth and Oriental fruit moth) and <800 Gy (according to quality results)

  11. Gamma irradiation as a phytosanitary treatment for fresh pome fruits produced in Patagonia

    Science.gov (United States)

    Pérez, J.; Lires, C.; Horak, C.; Pawlak, E.; Docters, A.; Kairiyama, E.

    2009-07-01

    Argentina produces 1.8 million tons/year of apples ( Malus domestica L.) and pears ( Pyrus communis L.) in the Patagonia region. Cydia pomonella, codling moth, and Grapholita molesta, Oriental fruit moth, ( Lepidoptera: Tortricidae) are quarantine pests in pome fruits. Irradiation is a promising phytosanitary treatment because a dose of 200 Gy completely prevents pest adult emergence. A pilot irradiation process of commercially packaged 'Red Delicious' apples and 'Packham's Triumph' pears was performed in an irradiation facility with a Cobalt 60 source. Quality analyses were carried out at 0, 2, 4, 6 and 8 months of storage (1 °C, RH 99%) to evaluate fruit tolerance at 200, 400 and 800 Gy. Irradiation at 200 and 400 Gy had no undesirable effects on fruit quality (pulp firmness, external colour, soluble solids content (SSC), titratable acidity (TA) and sensory evaluations). Irradiation of 'Red Delicious' apples and 'Packham's Triumph' pears can be applied as a commercial quarantine treatment with a minimum absorbed dose of 200 Gy (to control codling moth and Oriental fruit moth) and <800 Gy (according to quality results).

  12. A Middle Jurassic heterodontosaurid dinosaur from Patagonia and the evolution of heterodontosaurids

    Science.gov (United States)

    Pol, Diego; Rauhut, Oliver W. M.; Becerra, Marcos

    2011-05-01

    Heterodontosauridae is a morphologically divergent group of dinosaurs that has recently been interpreted as one of the most basal clades of Ornithischia. Heterodontosaurid remains were previously known from the Early Jurassic of southern Africa, but recent discoveries and studies have significantly increased the geographical and temporal range for this clade. Here, we report a new ornithischian dinosaur from the Middle Jurassic Cañadón Asfalto Formation in central Patagonia, Argentina. This new taxon, Manidens condorensis gen. et sp. nov., includes well-preserved craniomandibular and postcranial remains and represents the only diagnostic ornithischian specimen yet discovered in the Jurassic of South America so far. Derived features of its anatomy indicate that Manidens belongs to Heterodontosauridae, as the sister taxon of Heterodontosaurus and other South African heterodontosaurids. The presence of posterior dentary teeth with high crowns but lacking extensive wear facets in Manidens suggests that this form represents an intermediate stage in the development of the remarkable adaptations to herbivory described for Heterodontosaurus. The dentition of Manidens condorensis also has autapomorphies, such as asymmetrically arranged denticles in posterior teeth and a mesially projected denticle in the posteriormost teeth. At an estimated total length of 60-75 cm, Manidens furthermore confirms the small size of basal heterodontosaurids.

  13. Dietary analysis of Homonota darwini (Squamata: Gekkoni-dae in Northern Patagonia

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    Marcelo E. KUN, Carla PIANTONI, John D. KRENZ, Nora R. IBARGÜENGOYTÍA

    2010-08-01

    Full Text Available Our study investigated the diet of the southernmost gecko in the world, Homonota darwini. Fifty-three specimens were captured during spring and summer in four locations in Patagonia, Argentina. The stomach contents of the specimens were identified, and we found that prey consisted of six main groups: Coleoptera, Hymenoptera, Homoptera and Araneae, and the adults and larvae of moth Lepidoptera. Lepidoptera was the major dietary component. The presence of ants and moths as common prey suggests an ambush feeding strategy. In spring, females consumed more ants than males although no other dietary differences between males and females were evident. We found nine geckos with empty stomachs and six parasitized by nematodes. Presence of empty stomachs corroborates previous observations of other nocturnal geckos and non-gecko lizards. Reduced foraging success of nocturnal lizards could be due to difficulty in prey detection due to dim light, reduced or erratic activity of insect prey at night, or shorter activity times of geckos relative to diurnal success. Sex and season were not associated with the incidence of empty stomachs. Principal component analysis showed that four food alternatives correlated with season. The constraint of nocturnality, coupled with low night-time temperatures restricting feeding to only a few hours after sunset, appear to have caused a generality of diet which may limit energy acquisition. We conclude that H. darwini is an arthropod generalist and likely an ambush forager, as are many other nocturnal gekkonids [Current Zoology 56 (4: 406–410, 2010].

  14. Diseño de obras de control de aluviones basada en simulación de procesos hidrológicos torrenciales en cuencas de la Patagonia Design of alluvium control structures based on flash flood simulation in the Patagonia basins

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    Ana Cecilia Dufilho

    2001-05-01

    Full Text Available Fenómenos climáticos torrenciales que producen aluviones y grandes movimientos de sedimentos (bajo distintas formas son muy frecuentes en la Patagonia Argentina. Los estudios para el diseño de obras de control se realizan en general, a través de fórmulas empíricas sin verificar su aptitud a las condiciones patagónicas. En el presente trabajo se utilizan modelos matemáticos sencillos para la simulación hidrológica de crecidas en cuencas con escasa información hidrometeorológica y nula instrumentación. Esta metodología requiere estimar la lluvia de diseño asumiendo un nivel de riesgo, evaluar la eficiencia de distintos planes de control mediante simulaciones de distintas alternativas de obras y seleccionar aquella de menor costo.Climatic processes leading to flash flood and large sediment movements (under different forms are very frequent in Patagonia, Argentina. Often, projects of small reservoirs and levees are based on empirical formulations without a verification of their aptitude to the local conditions. In the present work, simple flood mathematical models are used for hydrological simulation in basins with scarce precipitation and flood data. This methodology requires estimation of the design storm associated with a risk level. It allows simulation and evaluation of alternative control projects, facilitating the selection of the least cost control scheme.

  15. Hasty retreat of glaciers in northern Patagonia

    Science.gov (United States)

    Paul, Frank; Mölg, Nico

    2014-05-01

    Mapping glacier extent from optical satellite data has become a most efficient tool to create or update glacier inventories and determine glacier changes over time. A most valuable archive in this regard is the nearly 30-year time series of Landsat Thematic Mapper (TM) data that is freely available (already orthorectified) for most regions in the world from the USGS. One region with a most dramatic glacier shrinkage and a missing systematic assessment of changes, is the Palena province in Chile, located south of Puerto Montt in northern Patagonia. A major bottleneck for accurate determination of glacier changes in this region is related to the huge amounts of snow falling in this very maritime region, hiding the perimeter of glaciers throughout the year. Consequently, we found only three years with Landsat scenes that can be used to map glacier extent through time. We here present the results of a glacier change analysis from six Landsat scenes (path-rows 232-89/90) acquired in 1985, 2000 and 2011 covering the Palena district in Chile and neighbouring regions. Clean glacier ice was mapped automatically with a standard technique (TM3/TM band ratio) and manual editing was applied to remove wrongly classified lakes and to add debris-covered glacier parts. The digital elevation model (DEM) from ASTER (GDEM2) was used to derive drainage divides, determine glacier specific topographic parameters, and analyse the area changes in regard to topography. The scene from the year 2000 has the best snow conditions and was used to eliminate seasonal snow in the other two scenes by digital combination of the binary glacier masks and neighbourhood analysis. The derived mean relative area loss over the entire study area is 25%, showing a large spatial variability and a strong dependence on elevation. While small mountain glaciers at high elevations and steep slopes show only little change over the 26-year period, ice at low elevations from large valley glaciers shows a dramatic

  16. (Misiones, Argentina

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    Gonzalo Márquez

    2006-01-01

    Full Text Available En la Reserva “Cuñá Pirú” se registraron un total de 9 familias, 29 géneros y 52 especies y taxones infraespecíficos. El género mejor representado es Asplenium con 8 especies, dos de ellas novedades para la flora argentina. El resto de los géneros tienen 1-3 especies. Estas plantas se hallan preferentemente en el interior de la selva y en el borde de los caminos y arroyos. Se presentan claves dicotómicas para la determinación de los grupos y entidades, como así también referencias bibliográficas, distribucionales y ecológicas.

  17. Contribution of the Patagonia Icefields of South America to Sea Level Rise

    National Research Council Canada - National Science Library

    Eric Rignot; Andrés Rivera; Gino Casassa

    2003-01-01

    Digital elevation models of the Northern and Southern Patagonia Icefields of South America generated from the 2000 Shuttle Radar Topography Mission were compared with earlier cartography to estimate...

  18. Isotopic and fluid-inclusion constraints on the formation of polymetallic vein deposits in the central Argentinian Patagonia

    Science.gov (United States)

    Dejonghe, Léon; Darras, Benoît; Hughes, Guillermo; Muchez, Philippe; Scoates, James S.; Weis, Dominique

    2002-03-01

    The lead isotope compositions of galena and the fluid-inclusion systematics of nine barite-bearing polymetallic (Au, Ag, Pb, Zn) deposits of the central Argentinian Patagonia (Chubut and Rio Negro provinces) have been investigated to constrain the compositions and sources of the mineralizing fluids. Most of the deposits occur as veins, with less common wall-rock disseminations and/or stockworks, and are low-sulfidation epithermal deposits hosted in Jurassic volcanic rocks. Fluid-inclusion homogenization temperatures (Th) from quartz and sphalerite from the deposits fall within the range of 100-300 °C, with the highest measured average temperatures for the most eastern deposits (Mina Angela - 298 °C; Cañadón Bagual - 343 °C). The salinities of the hydrothermal fluids at all deposits were low to moderate (≤10.4 equiv. wt% NaCl). Three groups of ore deposits can be defined on the basis of 206Pb/204Pb ratios for galena and these show a general decrease from west to east (from 18.506 to 18.000). The central Argentinian Patagonia deposits have distinctly less radiogenic lead isotope compositions than similar deposits from Peru and Chile, except for the porphyry copper deposits of central and southern Peru. Galena from the Mina Angela deposit is characterized by very low radiogenic lead isotope compositions (18.000copper systems remains an open question.

  19. On the hydrography of Puyuhuapi Channel, Chilean Patagonia

    Science.gov (United States)

    Schneider, Wolfgang; Pérez-Santos, Iván; Ross, Lauren; Bravo, Luis; Seguel, Romanet; Hernández, Freddy

    2014-12-01

    This work describes the hydrographic conditions found in Puyuhuapi Channel (northern Chilean Patagonia) during recent years on a seasonal scale. Puyuhuapi Channel was once a glacial valley, but the retreating ice allowed the inflow of marine waters. Five surveys were conducted between 2008 and 2012; historical data from 1995 to 2007 were included. A meteorological/oceanographic buoy was also installed in the northern section of Puyuhuapi Channel and was operational beginning on April 12th, 2011. Puyuhuapi Channel's surface characteristics highlight a fresher northern part and a more haline southern part except during winter when the pattern can reverse due to the intrusion of oceanic water via Jacaf Channel. The channel exhibits a highly variable meridional and seasonal vertical stratification, especially in its northern part where during spring and summer the water column is highly stratified but partially mixed during winter. Puyuhuapi Channel is the only fjord/channel with severe hypoxic conditions in all of Chilean Patagonia.

  20. Variation in the proximate composition and fatty acid profile recovered from Argentine hake (Merluccius hubbsi) waste from Patagonia

    Energy Technology Data Exchange (ETDEWEB)

    Cretton, M.; Rost, E.; Mazzuca-Sobczuk, T.; Mazzuca, M.

    2016-07-01

    The fish processing operations in Patagonia produce large amounts of waste. The main fishery resource in Argentina is the Argentine hake (Merluccius hubbsi). The ports of the province of Chubut (the most important of which are Puerto Madryn, Rawson and Comodoro Rivadavia), together with Caleta Paula Port (province of Santa Cruz), in the Argentine Patagonia, capture more than 82,000 tons of hake annualy, 80% of which are of M. hubbsi, which is mostly converted into fillets. From this capture, about 2,296 tons of liver would be available for the extraction of oil. To promote the recovery and industrial use of fish oil, in the present study, we determined the variation in the proximate composition and fatty acid profile of Argentine hake waste from the ports mentioned above at different catch times. Proximate composition was determined according of the Official Methods of Analysis (AOAC). Fatty acid profile was analyzed by gas chromatography of the fatty acid methyl esters (FAMEs). A standard mixture of FAMEs was run under identical conditions to identify the compounds on the basis of their retention times. Fatty acids were quantified using heptadecanoic acid (C17:0) as internal standard. The highest lipid recovery (27.0 to 41.8% of total lipids) was obtained from the liver fraction. Palmitic acid (C16:0), oleic acid (18:1 n9), docosahexaenoic acid (22:6 n3), eicosapentaenoic acid (20:5 n3) and palmitoleic acid (16:1) were the main constituents. Protein levels in viscera without livers (V-L) were higher than those in the liver. The extraction of marine fish oil and the production of fish offal meal from waste from fish factories would contribute to the sustainability of the regional industry, because it would also decrease the volume of waste, with benefits to the environment. (Author)

  1. Paleoecología: el uso de los quironómidos fósiles (Diptera: Chironomidae en reconstrucciones paleoambientales durante el Cuaternario en la Patagonia Paleoecology: the use of fossil chironomids (Diptera: Chironomidae for paleoenvironmental reconstructions in Patagonia

    Directory of Open Access Journals (Sweden)

    Julieta Massaferro

    2009-06-01

    Full Text Available Entre los indicadores biológicos lacustres más utilizados en las reconstrucciones ambientales, se encuentran el polen, los ostrácodos y las diatomeas, y entre los insectos, los coleópteros y los quironómidos. Este grupo ha cobrado gran importancia en los últimos tiempos, debido a los resultados prometedores que se han obtenido en reconstrucciones climáticas realizadas en América del Norte y Europa. En América del Sur, el uso de los quironómidos fósiles en estudios cuaternarios es relativamente limitado, principalmente por su escaso conocimiento taxonómico regional. La mayor parte de estos estudios fueron realizados en lagos glaciares patagónicos de Argentina y Chile. Las larvas de quironómidos constituyen una valiosa herramienta paleolimnológica, por ser un grupo de organismos altamente sensible a cambios ambientales, tanto naturales como artificiales. Además, es un grupo de insectos ampliamente distribuido y con una abundancia y diversidad relativamente altas. Sus cápsulas cefálicas se preservan en los sedimentos lacustres y poseen caracteres importantes que permiten identificar géneros y muchas veces especies. El estudio de los ensambles de quironómidos en sedimentos lacustres puede ser utilizado con distintos objetivos, por ejemplo, para estudios de eutrofización, ya que responden rápidamente a cambios en la concentración de nutrientes, materia orgánica y otros elementos, como metales pesados. No obstante, uno de los potenciales más importantes de este grupo de insectos es su sensibilidad a los cambios de temperatura, por este motivo, la aplicación más importante de su estudio en sedimentos se centra en las reconstrucciones climáticas. Esta contribución es una síntesis de los resultados de los trabajos publicados en la Patagonia argentina y chilena, sobre la base del uso de los quironómidos fósiles en reconstrucciones paleoambientales.Pollen, ostracods, diatoms and insects such as beetles and chironomids are

  2. Chaco, Argentina

    Directory of Open Access Journals (Sweden)

    E. O. Sanabria

    2007-01-01

    Full Text Available La producción de carbón de residuos de aserraderos de la especie Aspidosperma quebracho-blanco en la provincia del Chaco, Argentina, se realiza por medio de hornos convencionales, tipo media naranja con un rendimiento en peso de carbón de 25 % y un rendimiento en carbono fijo de 74 %. El objetivo del presente trabajo fue proponer una alternativa más eficiente del uso de residuos de aserraderos para optimizar el rendimiento en peso de carbón y el rendimiento en carbono fijo. Para ello, se procedió a fabricar carbón por destilación seca, de acuerdo a un diseño experimental compuesto controlando los siguientes parámetros: velocidad de calentamiento entre 60 y 120 ºC·h-1 y temperatura final de carbonización entre 450 y 550 ºC. Los resultados arrojan un rendimiento en peso de carbón del 48 % trabajando con una velocidad de calentamiento y temperatura final de carbonización baja, disminuyendo este rendimiento a un 36 %, cuando se trabaja a velocidades de calentamiento y temperaturas finales de carbonización, altas. En lo que respecta a rendimiento en carbono fijo, su comportamiento es de manera inversa en referencia a las variables antes mencionadas, pero siempre con un rendimiento superior al 82 %.

  3. Role of wild plant foods among late Holocene hunter-gatherers from Central and North Patagonia (South America): an approach from dental evidence.

    Science.gov (United States)

    Bernal, Valeria; Novellino, Paula; Gonzalez, Paula N; Perez, S Ivan

    2007-08-01

    This study evaluates the role of plant foods in the subsistence of hunter-gatherers that inhabited the Central East, Northwest, and Northeast Patagonia (Argentina) during the late Holocene (ca. 3,000-500 years BP). The goal of the present study is to assess the temporal variation of dental caries ratio and wear rate in skeletal samples to ascertain if the biological information supports the dietary shift toward greater consumption of wild plant foods around 1,500 years BP, suggested by other types of evidence. The authors registered caries, antemortem and postmortem tooth loss, and tooth wear from eight samples belonging to hunter-gatherers from Patagonia for which chronological sequences from early late Holocene (ca. 3,000-1,500 years BP) up to final late Holocene (ca. 1,500-500 years BP) are available. The results indicate that caries percentages in Patagonian samples fall within the range established for hunter-gatherers but there are significant geographical differences. In addition, caries ratio does not change significantly through time, so the amount of carbohydrates consumed seems to have remained fairly constant since 3,000 years BP. In contrast, there is a marked temporal trend toward the reduction of wear rates in the three areas, suggesting a faster rate in early late Holocene than in final late Holocene. These results would reflect a change to less hard and/or abrasive diets in the final late Holocene, probably owing to differences in food processing methods employed. (c) 2007 Wiley-Liss, Inc.

  4. Regulatory factors in crustacean zooplankton assemblages in mountain lakes of northern Chilean Patagonia (38-41°S: a comparison with Bulgarian counterparts (42°N Factores reguladores en ensambles de crustáceos zooplanctónicos en lagos de montaña del norte de la Patagonia chilena (38-41°S: una comparación con sus contrapartes de Bulgaria (42°N

    Directory of Open Access Journals (Sweden)

    Patricio De los Ríos-Escalante

    2012-07-01

    Full Text Available Chilean Patagonia has protected mountainous areas with evergreen native forests; in which the lakes and rivers, of volcanic or glacial origin, are oligotrophic. In Bulgaria, there are mountainous zones with native forests and associated lakes of volcanic origin. The aim of the present study is to carry out a preliminary comparison of zooplanktonic crustaceans in lake ecosystems associated with native forests of Chilean Patagonia and of Bulgarian mountains. The study revealed that the lakes studied in Chilean Patagonia are associated mainly with Nothofagus forests; they are oligotrophic, with a low number of zooplanktonic crustacean species. Similar results were observed for Bulgarian mountain lakes associated with Fagus forests. A null model analysis of species co-occurrence was applied to the two groups of lakes, and the result revealed the absence of regulatory factors in species associations. These studies agree with similar descriptions of lakes in Andean Patagonia and New Zealand. They highlight the important role of native Nothofagus forests in Argentina and Chile, and of Fagus forests with associated soil properties in Bulgaria, in the oligotrophy of the lakes studied.La Patagonia de Chile tiene una serie de áreas protegidas con bosques nativos perennes asociados a lagos y ríos oligotróficos y de origen glacial. Por otro lado en Bulgaria hay una serie de zonas montañosas con lagos asociados de origen volcánico o glacial. El objetivo del presente trabajo es realizar una primera descripción de especies de crustáceos zooplanctónicos en ecosistemas lacustres asociados a bosques nativos en la Patagonia de Chile y en las montañas de Bulgaria. Los estudios indican que los lagos de la Patagonia de Chile están asociados principalmente con bosques de Nothofagus, mientras que similares resultados fueron observados en lagos de Bulgaria con bosques de Fagus. La regresión lineal entre concentración de clorofila y número de especies para

  5. Mio-Pliocene glaciations of Central Patagonia: New evidence and tectonic implications Glaciaciones mio-pliocenas en Patagonia central: nueva evidencia e implicancias tectónicas

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    Yves Lagabrielle

    2010-07-01

    Full Text Available Patagonia is well known for spectacular oceurrences of a variety of glacial-derived landforms and deposits and for a long history of ancient glaciations. In this paper, we first review the diverse evidence that demonstrates the development of glacial-related sedimentary units within the Central Patagonian Cordillera since 7 Ma. Well preserved glacial landforms at the top surface of mesetas on both sides of the Lago General Carrera-Buenos Aires are described: the Meseta Guenguel to the north, and the volcanic Meseta del Lago Buenos Aires to the south. The latter meseta corresponds to a 3 Ma old, morphologically inverted paleo-piedmont, based on Ar/Ar dates of the uppermost lava flows. It shows evidence of glacier advances to the NE direction. Over a distance of 20 km, glacial landforms observed by remote sensing data and digital elevation model define glacial tongues that were fed by the Cordillera reliefs to the west. These lobes are now beheaded from their westward sources along a morpho-structural corridor that bounds the Meseta del Lago Buenos Aires to the west. These remnants can be correlated with the oldest glacial landforms recognized north of Lago General Carrera-Buenos Aires, on the Meseta Guenguel that form the Chipanque moraine system. From these features it is concluded that the glacial drainage network of Central Patagonia has been strongly modified following relief inversion in response to erosion processes and to tectonic causes. Changes occurred after 3 Ma, from a smooth piedmont surface covered by an extensive ice mantle ending with ampie glacial lobes, to the current series of deeply incised glacial valleys such as the Lago General Carrera-Buenos Aires depression. These new data bear important con-straints on the history and development of the first glaciations in southern South America.Patagonia es bien conocida por una espectacular geomorfología glacial y por una larga historia de antiguas glaciaciones. En este art

  6. A new species of monorchiid digenean from marine fishes in the Southwestern Atlantic Ocean off Patagonia.

    Science.gov (United States)

    Carballo, María Cecilia; Laurenti, Sonia; Cremonte, Florencia

    2011-03-01

    Proctotrema bartolii n. sp. (Digenea: Monorchiidae) is described based on naturally and experimental obtained adults from the marine fishes Odontesthes smitti (Lahille), O. nigricans (Richardson) (Atherinopsidae) and Eleginops maclovinus (Cuvier) (Eleginopidae) off Patagonia, Argentina, in the Southwestern Atlantic Ocean. Its generic identification is based on the presence of a unipartite terminal organ with the metraterm uniting with its distal region, an unarmed genital atrium, a single testis, a vitellarium follicular lateral to the ovary and ventral sucker, and uterine coils occupying most of hindbody. The new species differs from P. bacilliovatum Odhner, 1911, P. amphitruncatum Fischthal & Thomas, 1969 and P. guptai Ahmad & Dhar, 1987 in having a smaller body (305-650 vs 1,600-3,080, 1,500-1,800 and 2,150-2,670 μm, respectively), a round vs funnel-shaped oral sucker, a smooth vs lobed ovary, a saccular rather than tubular excretory vesicle, the number of vitelline follicles (12-16 vs 8-9, 9 and 6-8, respectively), and wider eggs (25-31 × 15-20 vs 28-37 × 9-12, 24-28 × 7-10, and 24-30 × 8-10 μm, respectively). Moreover, the new species differs from P. bacilliovatum and P. amphitruncatum in having a saccular rather than a coiled seminal vesicle, and from P. bacilliovatum and P. guptai in having its tegument completely vs partly spined. Proctotrema Odhner, 1911 is considered to be restricted to these four species. This is the first report of a species of this genus from South American waters.

  7. Litter and soil properties are not altered by invasive deer browsing in forests of NW Patagonia

    Science.gov (United States)

    Relva, María Andrea; Castán, Elisa; Mazzarino, María Julia

    2014-01-01

    It is largely accepted that large mammalian herbivores can indirectly influence ecosystem properties by changing the quantity and quality of litter inputs to soil through selective browsing on plant communities. However, idiosyncratic effects (positive, neutral and negative) have been found for different vegetation types, herbivory and soil properties. In this study we tested whether browsing by exotic deer introduced into Patagonian forests 90 years ago alters physical, chemical and biological soil properties and litter quantity and quality. As in many terrestrial ecosystems, N is the main nutrient that limits plant growth in Patagonia. Consequently, any disturbance that alters the N cycle, such as changes in the type or intensity of herbivory, is expected to affect these forest ecosystems. We compared soil and total litter from inside and outside five 7-yr old exclosures located on Isla Victoria, Parque Nacional Nahuel Huapi, Argentina. Despite introduced deer has significantly affected the composition, abundance and structure of the understory vegetation, we found no differences between browsed and unbrowsed areas in the physical (bulk density, moisture), chemical (pH, base cations, organic C and total N) and biological (potential microbial respiration and net N mineralization) soil properties. This could be attributable to the high capacity of volcanic soils to stabilize organic matter, buffering disturbance-induced changes. However, the quantity and quality (C, N and C/N ratio) of total litter were also not different between browsed and unbrowsed areas. Although non-significant differences were found between treatments in both compartments, litter and soil, most variables showed a slight trend toward higher values in unbrowsed areas. This suggests that 7 years of browsing exclusion would be not enough to detect changes induced by browsing, particularly in highly stable volcanic soils.

  8. Isolation and molecular characterization of Clostridium perfringens from healthy Merino lambs in Patagonia region, Argentina.

    Science.gov (United States)

    Mignaqui, A C; Marcellino, R B; Ronco, T; Pappalardo, J S; Nonnemann, B; Pedersen, K; Robles, C A

    2017-02-01

    The presence and molecular characterization of Clostridium perfringens in healthy Merino lambs over a six-month period was investigated in this study. Overall, a high prevalence of C. perfringens was detected, even in day-old lambs. Even though the majority of the isolates were characterized as being of type A, types C and D were also isolated. Furthermore, a high genetic diversity was observed by PFGE among the type A isolates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Ecology of cultivable yeasts in pristine forests in northern Patagonia (Argentina) influenced by different environmental factors.

    Science.gov (United States)

    Mestre, María Cecilia; Fontenla, Sonia; Rosa, Carlos A

    2014-06-01

    Environmental factors influencing the occurrence and community structure of soil yeasts in forests are not well studied. There are few studies dedicated to Southern Hemisphere soil yeasts populations and even fewer focused on temperate forests influenced by volcanic activity. The present work aimed to study the ecology of soil yeast communities from pristine forests influenced by different environmental factors (precipitation, physicochemical properties of soil, tree species, soil region, and season). The survey was performed in 4 northern Patagonian forests: 2 dominated by Nothofagus pumilio and 2 by Nothofagus antarctica. Yeast communities were described with ecological indices and species accumulation curves, and their association with environmental characteristics was assessed using multivariate analysis. Each forest site showed a particular arrangement of species as a result of environmental characteristics, such as dominant plant species, nutrient availability, and climatic characteristics. Cryptococcus podzolicus was most frequently isolated in nutrient-rich soils, Trichosporon porosum dominated cold mountain forests with low nutrient and water availability in soil, and capsulated yeasts such as Cryptococcus phenolicus dominated forest sites with low precipitation. The present work suggests that environmental factors affecting yeast communities may not be the current soil characteristics but the result of complex interactions of factors including natural disturbances like volcanic activity.

  10. Natural and anthropogenic hydrocarbons in sediments from the Chubut River (Patagonia, Argentina).

    Science.gov (United States)

    Commendatore, M G; Esteves, J L

    2004-05-01

    In March of 2001 a study was carried out to evaluate hydrocarbon levels in the lower course of the Chubut River. The study included 12 sample stations along the river from San Cristóbal Bridge to the confluence with the sea, in a 25 km straight-line extension in a urbanized area. In the first 11 stations, resolved aliphatic (RAli) hydrocarbons presented low values, between 0.07 and 0.96 microg/g dry weight (dw); the unresolved complex mixture (UCM) between 0.42 and 2.72 microg/g dw, and the total aliphatic (TAli) hydrocarbons between 0.55 and 3.07 microg/g dw. In the last station, at the mouth of Chubut river, these values increased to 460, 284, and 741 microg/g dw for RAli, UCM and TAli, respectively. The n-alkanes distribution indices and the compositional parameters suggested a predominantly biogenic origin in eleven stations, and a predominantly anthropogenic origin in the last station, with the highest hydrocarbon values. It is possible to conclude that the stations with low hydrocarbon values and biogenic origin predominance would constitute the baseline of aliphatic hydrocarbons for river sediments at this zone. The station with the highest hydrocarbon concentration and predominantly anthropic origin was related to the presence of Rawson city's port, where its activities (harbor and fishing vessels) generate hydrocarbon wastes unrelated to the river base profile in the study zone. Offshore, but within the river influence, there is an important fishing area of Argentine Red and Patagonian shrimps (Pleoticus muelleri and Artemesia longinaris, respectively).

  11. First record of the invasive algae Didymosphenia geminata in the Lake Nahuel Huapi: Argentina, Patagonia

    OpenAIRE

    Beamud, Sara Guadalupe; Baffico, Gustavo Daniel; Pedrozo, Fernando Luis; Diaz, Monica Mabel

    2016-01-01

    The benthic diatom Didymosphenia geminata (L yngbye) M. Schmidt is a ver y aggressive invasive species found in riversand streams in different parts of the world. It has become a major concern for its tendency to form conspicuous blooms in oligotrophic aquatic systems with potential for detrimental impacts on recreational fi shing. Given its explosive development and the notable appearance in Lake Nahuel Huapi during the austral summer of 2013, our aim was to document the fi rst record fo...

  12. Managing Sirex noctilio populations in Patagonia (Argentina): silviculture and biological control

    Science.gov (United States)

    José Villacide; Deborah Fischbein; Nélida Jofré; Juan. Corley

    2010-01-01

    Sirex noctilio is a primitive wood boring solitary wasp with a univoltine life cycle. Characteristic of this species is the occurrence of severely damaging, pulse-like eruptive population outbreaks. During outbreaks, the damage to pine plantations can be severe; tree mortality may reach levels close to 80 percent. Outbreak behavior is thus important...

  13. Isolation and molecular characterization of Clostridium perfringens from healthy Merino lambs in Patagonia region, Argentina

    DEFF Research Database (Denmark)

    Mignaqui, A. C.; Marcellino, R. B.; Ronco, Troels

    2017-01-01

    The presence and molecular characterization of Clostridium perfringens in healthy Merino lambs over a six-month period was investigated in this study. Overall, a high prevalence of C. perfringens was detected, even in day-old lambs. Even though the majority of the isolates were characterized as b...

  14. Diversos usos instrumentales del aparato masticatorio en restos humanos de la Patagonia Argentina

    Directory of Open Access Journals (Sweden)

    Kozameh, Livia Febes

    2005-01-01

    Full Text Available Desgastes dentarios atípicos y disarmónicos, asociados a patologías sugirieron la posibilidad que los mismos se hubieran producido por una actividad masticatoria excesiva y no alimentaria. La variedad de rastros registrados sugiere el uso de la boca con fines instrumentales, como recurso posiblemente constante. Los casos seleccionados son seis y sus rasgos predominantes se describen sucintamente. 1 Muestra dentaria de canoeros fueguinos. Fracturas cuspídeas pulimentadas únicamente en denticiones femeninas.2Resto de cazador canoero del Beagle. Notables desgastes dentarios con distintas angulaciones a modo de zigzag. Raíces en función oclusal con procesos alveolares concomitantes. 3Resto de cazador pedestre de Tierra del Fuego. Disminución del tamaño coronal de los dientes anteriores y primeros premolares, con pérdida completa de su morfología. Los bordes incisales exhiben tres planos de desgaste con diferentes direcciones. 4 y 5Cazadores de Santa Cruz. En uno de ellos los desgastes coronales son convexos en todos sus dientes. Patologías alveolares. En el otro ejemplar el desgaste tornó cilíndricas las coronas de las piezas anteriores. 6Resto femenino de Chubut. Pérdida prematura de los cuatro dientes anteriores con compromiso óseo y canino transpuesto.

  15. Ultraviolet radiation and primary productivity in temperate aquatic environments of Patagonia (Argentina)

    NARCIS (Netherlands)

    Villafañe, Virginia

    2004-01-01

    Numerous studies carried out since the discovery of the ozone “hole” over the Antarctic continent have motivated photobiological research to determine the potential effects of increased solar ultraviolet radiation – UV-B (280-315 nm) on organisms and ecosystems. Since then, the amount of literature

  16. Taxonomy and ecology of metazoan parasites of otariids from Patagonia, Argentina : adult and infective stages

    OpenAIRE

    Hernández Orts, Jesús Servando

    2013-01-01

    At present, the metazoan parasite fauna of most species of otariids is generally poorly known, in part because these marine mammals are mostly protected and, therefore, sampling is limited to specimens stranded on the coast or captured as by-catch in fisheries. Similar problems also occur for the larval stages of gastrointestinal helminths of otariids. For most of these parasite species, the specific identity of the intermediate/paratenic of hosts is unknown and, therefore, many stages of the...

  17. Multiple territories in dispute : water policies, participation and Mapuce indigenous rights in Patagonia, Argentina

    NARCIS (Netherlands)

    Moreyra, A.

    2009-01-01

    This thesis is about the multiple territories which dispute the shape and control of the development of the Trahunco-Quitrahue watershed, at Cerro Chapelko, Neuquén province in Argentinean Patagonian. Built into these disputes are the struggles of Mapuce peoples -indigenous peoples of the region-

  18. Subantarctic forest ecology : case study of a conifer-broadleaved stand in Patagonia, Argentina

    NARCIS (Netherlands)

    Dezzotti, A.

    2000-01-01

    In the temperate rainforests of southern South America, the tree genus Nothofagus (Nothofagaceae) is the dominant in extension and abundance on zonal soils at different latitudes and altitudes, as well as on intrazonal (e.g., wetlands) and azonal soils (e.g., morrenic

  19. Analysis of the Aeromagnetic Anomalies of the Auca Mahuida Volcano, Patagonia, Argentina

    Science.gov (United States)

    Longo, L. M.; De Ritis, R.; Ventura, G.; Chiappini, M.

    2016-10-01

    We present the analysis of the subsurface structure of the Auca Mahuida volcano based on high-resolution aeromagnetic data integrated with the available geological information. Most of the detected magnetic anomalies have a dipolar structure opposite to that of the present geomagnetic field. According to the available geochronological data and paleomagnetic measurements, the source bodies of Auca Mahuida mainly emplaced in the Matuyama reverse polarity chron. The Reduction-to-the-Pole map confirms that the magnetization direction is mainly reverse with only few anomalies normally magnetized. Two opposite, coexisting polarities do not allow to fully remove the dipolar character of the field in the Reduction-to-the-Pole transformation. Therefore, we model the measured anomaly field by applying analytical techniques that are independent of the magnetization direction. The obtained anomaly strikes and source geometries indicate an emplacement of intrusive bodies controlled by the regional faults affecting the Auca Mahuida basement and the sedimentary successions of the Neuquén basin. Magma upraised along these faults and fractures feeding the volcanic activity and subsequently crystallized. The averaged power spectrum and Euler Deconvolution indicate source depths consistent with those of the intrusions recognized in wells. Borehole data highlight the widespread presence of intrusive bodies below the Auca Mahuida central crater and the peripheral sectors at depth of 2 km below sea level. These bodies have played a major role in the thermal maturation of hydrocarbons and in the subsequent accumulation of oil below the volcano. The obtained results shed light on the Auca Mahuida feeding system and on the intrusions geometry, also pointing out the effectiveness of the magnetic prospecting in the oil industry even in presence of strong remanent magnetization.

  20. Isolation and molecular characterization of Clostridium perfringens from healthy Merino lambs in Patagonia region, Argentina

    DEFF Research Database (Denmark)

    Mignaqui, A. C.; Marcellino, R. B.; Ronco, Troels

    2017-01-01

    The presence and molecular characterization of Clostridium perfringens in healthy Merino lambs over a six-month period was investigated in this study. Overall, a high prevalence of C. perfringens was detected, even in day-old lambs. Even though the majority of the isolates were characterized...

  1. Crustal Thickness and Structure in Southern Chile: Patagonia plate assembly structures and continental arc modifications

    Science.gov (United States)

    Rodriguez, E. E.; Russo, R. M.

    2016-12-01

    Crustal structure is the product of the processes that operated during a region's tectonic history. For Patagonia, these tectonic processes include its early Paleozoic assembly and accretion to the South America portion of Gondwana, Triassic rifting of Gondwana, and a long history as the upper plate during oceanic subduction since the Mesozoic. To assess the crustal structure and glean insight into how these tectonic processes affected the region, we combined data from two seismic networks, the Chile Ridge Subduction Project and Seismic Experiment of Aisen Chile - yielding a total of 77 broadband seismic stations - deployed from 2004 to 2007. The stations were concentrated 300 km inboard of the Chile trench, above structures unlikely to have been affected by ongoing Chile Ridge subduction. Events suitable for receiver function (RF) analyses (M > 5.9, of various backazimuths, epicentral distances of 30 - 90°) yielded 995 radial RFs, constructed using iterative time deconvolution (Ligorria and Ammon, 1999). We estimated crustal thicknesses and compressional to shear wave velocity ratios (Vp/Vs) using the H-k grid search method (Zhu and Kanamori, 2000); common conversion point (CCP) stacking (Zhu, et al., 2006) allowed imaging of crustal structure. Results limit crustal thicknesses to between 30 and 45 km. The crust varies smoothly from 30 km at the N margin of our study area ( 43°S) to a max depth of 45 km at 44.75°S, shallowing to 30 km at 49°S. On E-W CCP sections north of 46°S, the Moho dips westward, from a depth of 35 at 71°W to 45 km at its deepest near 72.75°W. Beneath the active Southern Volcanic Zone, which is bounded to the west by the Liquiñe-Ofqui fault, the Moho is ambiguous, producing unclear Ps phases possibly reflecting a lack of sharp impedance contrast or poor conversion efficiency at the base of the crust, perhaps due to deep-seated volcanic arc processes. The proximity of the Liquiñe-Ofqui strike-slip fault may also complicate the

  2. Europeans and US nationals in Northern Andean Patagonia: new experiences

    Directory of Open Access Journals (Sweden)

    Brenda Matossian

    2014-09-01

    Full Text Available The financial crisis has produced a relatively new type of mobility from northern countries towards Latin America. This article discusses the integration of migrants of European and US origin into Northern Andean Patagonia, a tourism-oriented area of outstanding natural beauty. The use of statistical data and qualitative-interpretative instruments shows that this migration has gained importance within the framework of «dissatisfaction-driven migration», as opposed to «deficiency-driven migration». The territorial expression of the phenomenon is not homogeneous within the region. However, the emergence of new socio-territorial and cultural processes merits analysis.

  3. Tradiciones culturales y evolución en Patagonia

    OpenAIRE

    Orquera, Luis Abel

    1985-01-01

    El tema de esta comunicación está constituido por lagunas reflexiones acerca de la prehistoria de Patagonia que estaban destinadas a ser presentadas en la mesa redonda sobre las industrias más antiguas de esa subárea de nuestro territorio. Parto para ellas de la base de que la arqueología, si realmente quiere merecer el calificativo de científica y no constituir simplemente un ejercicio de imaginación, ha de apoyarse sobre observaciones debidamente controladas y documentadas y sobre hipótesis...

  4. Patagonia Wind - Hydrogen Project: Underground Storage and Methanation

    OpenAIRE

    Perez, Ariel; Pérez, E.; Dupraz, Sebastien; Bolcich, J.

    2016-01-01

    International audience; The estimated 2,000 GW wind power potential of Argentine Patagonia, its natural resources and infrastructure are the best combination for a Large Scale Wind-Hydrogen production in Hychico´s vision. A Hydrogen Plant producing 120 Nm3/h (99,998 % purity), and a Wind Park (6.3 MW), with an average annual capacity factor of 50% constitute the first stage of Hychico’s program. This “Green” or zero emission hydrogen will supply developing markets such as fuel cell, and or in...

  5. Adapting to Water Stress in the Comahue Region of Argentina ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Climate change is expected to lead to decreases in annual precipitation for the Comahue region in central-west Argentina. Combined with a projected increase in water demand and use, this will likely result in more frequent and severe water shortages over the coming decades. Water access and distribution in the region is ...

  6. Variation in the proximate composition and fatty acid profile recovered from Argentine hake (Merluccius hubbsi waste from Patagonia

    Directory of Open Access Journals (Sweden)

    Cretton, M.

    2016-03-01

    Full Text Available The fish processing operations in Patagonia produce large amounts of waste. The main fishery resource in Argentina is the Argentine hake (Merluccius hubbsi. The ports of the province of Chubut (the most important of which are Puerto Madryn, Rawson and Comodoro Rivadavia, together with Caleta Paula Port (province of Santa Cruz, in the Argentine Patagonia, capture more than 82,000 tons of hake annualy, 80% of which are of M. hubbsi, which is mostly converted into fillets. From this capture, about 2,296 tons of liver would be available for the extraction of oil. To promote the recovery and industrial use of fish oil, in the present study, we determined the variation in the proximate composition and fatty acid profile of Argentine hake waste from the ports mentioned above at different catch times. Proximate composition was determined according of the Official Methods of Analysis (AOAC. Fatty acid profile was analyzed by gas chromatography of the fatty acid methyl esters (FAMEs. A standard mixture of FAMEs was run under identical conditions to identify the compounds on the basis of their retention times. Fatty acids were quantified using heptadecanoic acid (C17:0 as internal standard. The highest lipid recovery (27.0 to 41.8% of total lipids was obtained from the liver fraction. Palmitic acid (C16:0, oleic acid (18:1 n9, docosahexaenoic acid (22:6 n3, eicosapentaenoic acid (20:5 n3 and palmitoleic acid (16:1 were the main constituents. Protein levels in viscera without livers (V-L were higher than those in the liver. The extraction of marine fish oil and the production of fish offal meal from waste from fish factories would contribute to the sustainability of the regional industry, because it would also decrease the volume of waste, with benefits to the environment.El procesamiento de pescados en Patagonia produce gran cantidad de residuos. El recurso de pesca más importante en la Argentina es la merluza argentina (Merluccius hubbsi. En Patagonia

  7. Water Law, Mining and Hydro-Energy Conflicts in South America: Tales from the Andes and Patagonia

    Directory of Open Access Journals (Sweden)

    Victor Tafur

    2011-10-01

    Full Text Available Conflicts in connection with hydro-energy and mining activities vis-à-vis other water uses, mainly human consumption, agriculture, industry, tourism, or even the essential flows needed for ecosystem protection, call into question whether South America’s path in the 21st Century will be characterized as ‘open veins’ (borrowing from the title of Uruguayan writer Eduardo Galeano’s book or sustainable development. In this era of ‘New Conquistadors’, as some have called it, the key question is whether water law and environmental legal frameworks in the region are fit to deal with the pressure posed by these extracting industries. The paper seeks to contribute to this debate by discussing legal issues in connection with a controversial gold mining project in the Argentina-Chile border and a hydro-energy project in the Chilean Patagonia. The goal of the paper is to provide a South American perspective of water law through the lens of conflict. The paper concludes that water-related conflicts in these projects reveal weaknesses in the regulatory scheme for such endeavours and underscores the need to adopt reforms or implement mechanisms to ensure that water resources are adequately assessed, protected, and monitored.

  8. Using glacial morphology to constrain the impact of the Chile active spreading ridge subduction in Central Patagonia

    Science.gov (United States)

    Scalabrino, B.; Ritz, J. F.; Lagabrielle, Y.

    2009-04-01

    front and the western side of the meseta del Lago Buenos Aires. (ii) Further north, the meseta del Cerro Galera exhibits a sequence of more than 200 m thick tills and fluvio-glacial deposits which top of is at 1500 m. This perched sequence shows accumulation of polygenic material, which sources are situated 100 to 150 km westwards. The glacial sequence of Cerro Galera is situated more than 1000 meters above the tectonic-controlled depression of Coihaique where younger (Pleistocene) glacial deposits have been identified. As observed along the western margin of the Meseta del Lago Buenos Aires, the till is presently disconnected from any former glacial morphology to the west. This feature can be attribute to a major fault zone west to the meseta del Cerro Galera. In summary, we demonstrate that the location of pre-Quaternary glacial markers found as preserved on perched relict surfaces at around 1500-2000 meters whereas the location of Quaternary glacial deposits are 1000 meters below within the present-day glacial valleys suggest a drastic change in the glacial drainage network of the Central Patagonia. This change can be attributed to the extensional/transtensional tectonics responsible for the formation of transverse depressions and oblique tectonic corridors, which occurred between 3 Ma and 1 Ma. Geodynamically, this recent phase has been closely related with the subduction of the South Chile Ridge. The development of a large slab window beneath the Central Patagonian Cordillera since 3 Ma allowed hot mantle to reach sub-lithospheric regions, producing a weakening of the crust triggering in turn localized collapse.

  9. Sub-recent volcanism in Northern Patagonia: A tectonomagmatic approach

    Science.gov (United States)

    Massaferro, Gabriela I.; Haller, Miguel J.; D'Orazio, Massimo; Alric, Viviana I.

    2006-07-01

    The Crater Basalt Volcanic Field (CBVF) in northern Patagonia (˜42°S, Chubut province) is located 400 km eastward of the current Peru-Chile Trench and to the southwest of the Meseta de Somuncura, in a back-arc position in the extra-Andean Patagonia. The CBVF lava flows cover glaciation related terraces and present stream valleys. The occurrence of CBVF is related with the Gastre Fault System (GFS), a very significant tectonic feature about 40 km wide. The CBVF volcanics cover a surface of ˜700 km 2, occurring mainly as lava flows and scoria cones. CBVF volcanics have relatively high contents of MgO (6-9 wt.%), Cr (136-289 ppm) and Ni (25-198 ppm), and classify as alkali basalts, basanites and trachybasalts. Geothermometry indicates a crystallization temperature of ˜1140 °C and a ƒO 2 of - 1.0 1 to 0.0 (log FMQ units). The petrographic and geochemical characteristics of CBVF products suggest that the magma originated from a garnet-bearing lherzolite mantle source with asthenospheric characteristics, as a result of decompression, partial melting and ascent. These melts would have risen through a system of deep faults like the Gastre Fault System, following the last Quaternary glacial event.

  10. Niche Segregation between Wild and Domestic Herbivores in Chilean Patagonia

    Science.gov (United States)

    Iranzo, Esperanza C.; Traba, Juan; Acebes, Pablo; González, Benito A.; Mata, Cristina; Estades, Cristián F.; Malo, Juan E.

    2013-01-01

    Competition arises when two co-occuring species share a limiting resource. Potential for competition is higher when species have coexisted for a short time, as it is the case for herbivores and livestock introduced in natural systems. Sheep, introduced in the late 19th century in Patagonia, bear a great resemblance in size and diet to the guanaco, the main native herbivore in Patagonia. In such circumstances, it could be expected that the two species compete and one of them could be displaced. We investigated spatial overlap and habitat selection by coexisting sheep and guanaco in winter and in summer. Additionally, we studied habitat selection of the guanaco in a control situation free from sheep, both in summer and winter. We also determined overlap between species in areas with different intensity of use (named preferred and marginal areas) in order to further detect the potential level of competition in the case of overlapping. Guanaco and sheep showed significantly different habitat preferences through all seasons, in spite of their spatial overlap at landscape scale. Additionally, the habitat used by guanaco was similar regardless of the presence or absence of livestock, which further indicates that sheep is not displacing guanaco where they coexist. These results suggest that habitat segregation between guanaco and sheep is due to a differential habitat selection and not to a competitive displacement process. Therefore, the potential for competition is considered low, contrary to what has been previously observed, although this could be a density-dependent result. PMID:23555656

  11. Diplodon shells from Northwest Patagonia as continental proxy archives: Oxygen isotopic results and sclerochronological analyses

    Science.gov (United States)

    Soldati, A. L.; Beierlein, L.; Jacob, D. E.

    2009-04-01

    Freshwater mussels of the genus Diplodon (Bivalvia, Hyriidae) are the most abundant bivalve (today and in the past) in freshwater bodies at both sides of the South-Andean Cordillera. There are about 25 different Diplodon genera in Argentina and Chile that could be assigned almost completely to the species Diplodon chilensis (Gray, 1828) and two subspecies: D. ch. chilensis and D. ch. patagonicus; this latter species is found in Argentina between Mendoza (32˚ 52' S; 68˚ 51' W) and Chubut (45˚ 51' S; 67˚ 28' W), including the lakes and rivers of the target area, the Nahuel Huapi National Park (Castellanos, 1960). Despite their wide geographic distribution, Diplodon species have only rarely been used as climate archives in the southern hemisphere. Kaandorp et al. (2005) demonstrated for Diplodon longulus (Conrad 1874) collected from the Peruvian Amazonas that oxygen isotopic patterns in the shells could be used in order to reconstruct the precipitation regime and dry/wet seasonal of the monsoonal system in Amazonia. Although this study demonstrated the potential of Diplodon in climatological and ecological reconstructions in the southern hemisphere, as of yet, no systematic study of Diplodon as a multi-proxy archive has been undertaken for the Patagonian region. In this work we present sclerochronological analyses supported by ^18Oshell in recent mussel of Diplodon chilensis patagonicus (D'Orbigny, 1835) collected at Laguna El Trébol (42°S-71°W, Patagonia Argentina), one of the best studied water bodies in the region for paleoclimate analysis. Water temperature was measured every six hours for one year using a temperature sensor (Starmon mini®) placed at 5m depth in the lake, close to a mussel bank. Additionally, ^18Owater was measured monthly for the same time range.g^18Oshell values obtained by micro-milling at high spatial resolution in the growth increments of three Diplodon shells were compared to these records, and to air temperature and

  12. Checklist of the Discomycetes (Fungi of Patagonia, Tierra del Fuego and adjacent antarctic areas

    Directory of Open Access Journals (Sweden)

    Irma J. Gamundí

    2004-01-01

    Full Text Available La información brindada en este catálogo consiste en registrar las especies de hongos pertenecientes a los órdenes Cyttariales, Helotiales, Ostropales, Pezizales, Rhytismatales y Thelebolales (Discomycetes coleccionadas en Patagonia, Tierra del Fuego y áreas adyacentes antárticas (Patagonia. Además datos sobre sus organismos asociados fueron localizados, resumidos, validados y editados. Las fuentes de información fueron las exsiccatae depositadas en colecciones de Argentina y otros países y de las publicaciones listadas en la bibliografía. Otros registros derivaron de observaciones de campo sobre material fresco y colecciones de referencia. La información fue acumulada en un sistema computarizado relacional de datos taxonómicos, nomenclaturales, bibliográficos, de distribución geográfica y de observaciones biológicas. Este sistema permite la acumulación de datos paralelos en diferentes idiomas, y distingue la información original de la opinión corriente de lo que puede significar esa información. En la Biological Records Database, 5029 registros fueron creados para observaciones sobre la ocurrencia temporal y espacial de los organismos vivos de la región. De éstos, 2613 corresponden a registros de colecciones de Discomycetes de la Patagonia y Tierra del Fuego, con la siguiente distribución: 1854 para a la Argentina, 687 para Chile y 72 para áreas adyacentes antárticas. Excluyendo los sinónimos, los Discomycetes están representados por 361 especies y taxones subespecíficos (160 géneros, 22 familias y 7 órdenes. Los registros remanentes fueron de organismos asociados con los Discomycetes: 163 animales (8 especies, 8 géneros, 6 familias y 5 órdenes; 2 Chromista; 223 hongos (52 especies, 54 géneros, 26 familias y 13 ódenes; 2028 plantas (159 especies, 122 géneros, 59 familias y 39 órdenes. Cada uno de estos taxones (y cada sinónimo conocido está representado por un registro separado en la Base de Datos Taxon

  13. Medical revolution in Argentina.

    Science.gov (United States)

    Ballarin, V L; Isoardi, R A

    2010-01-01

    The paper discusses the major Argentineans contributors, medical physicists and scientists, in medical imaging and the development of medical imaging in Argentina. The following are presented: history of medical imaging in Argentina: the pioneers; medical imaging and medical revolution; nuclear medicine imaging; ultrasound imaging; and mathematics, physics, and electronics in medical image research: a multidisciplinary endeavor.

  14. Late Cretaceous-early Eocene counterclockwise rotation of the Fueguian Andes and evolution of the Patagonia-Antarctic Peninsula system

    Science.gov (United States)

    Poblete, F.; Roperch, P.; Arriagada, C.; Ruffet, G.; Ramírez de Arellano, C.; Hervé, F.; Poujol, M.

    2016-02-01

    The southernmost Andes of Patagonia and Tierra del Fuego present a prominent arc-shaped structure: the Patagonian Bend. Whether the bending is a primary curvature or an orocline is still matter of controversy. New paleomagnetic data have been obtained south of the Beagle Channel in 39 out of 61 sites. They have been drilled in Late Jurassic and Early Cretaceous sediments and interbedded volcanics and in mid-Cretaceous to Eocene intrusives of the Fuegian Batholith. The anisotropy of magnetic susceptibility was measured at each site and the influence of magnetic fabric on the characteristic remanent magnetizations (ChRM) in plutonic rocks was corrected using inverse tensors of anisotropy of remanent magnetizations. Normal polarity secondary magnetizations with west-directed declination were obtained in the sediments and they did not pass the fold test. These characteristic directions are similar to those recorded by mid Cretaceous intrusives suggesting a remagnetization event during the normal Cretaceous superchron and describe a large (> 90°) counterclockwise rotation. Late Cretaceous to Eocene rocks of the Fueguian Batholith, record decreasing counterclockwise rotations of 45° to 30°. These paleomagnetic results are interpreted as evidence of a large counterclockwise rotation of the Fueguian Andes related to the closure of the Rocas Verdes Basin and the formation of the Darwin Cordillera during the Late Cretaceous and Paleocene. The tectonic evolution of the Patagonian Bend can thus be described as the formation of a progressive arc from an oroclinal stage during the closure of the Rocas Verdes basin to a mainly primary arc during the final stages of deformation of the Magallanes fold and thrust belt. Plate reconstructions show that the Antarctic Peninsula would have formed a continuous margin with Patagonia between the Early Cretaceous and the Eocene, and acted as a non-rotational rigid block facilitating the development of the Patagonian Bend.

  15. PATAGONIA: DEL PRESENTE ETNOGRÁFICO AL PASADO ARQUEOLÓGICO (Patagonia: from the ethnographic present to the archaeological past

    Directory of Open Access Journals (Sweden)

    Arturo Sáez

    2011-03-01

    Full Text Available En este trabajo se analizan los principales argumentos utilizados desde diferentes perspectivas paleo-biológicas, paleo-lingüísticas, arqueológicas y antropológicas para explicar la diversidad y la conformación étnica de las poblaciones indígenas en Patagonia, tanto en el presente como en el pasado. Entendemos que una revisión conjunta y crítica de los supuestos disciplinares, sobre los cuales se continúa trabajando, permitirá observar e identificar los patrones que emergen del registro histórico, concernientes a la expresión de la variabilidad social patagónica. De igual modo, se propone una reflexión sobre las posibles proyecciones que plantea esta crítica hacia la exploración y la formulación de nuevas preguntas sobre el registro arqueológico. ENGLISH: This paper analyzes some of the main arguments from paleobiology, paleolinguistics, archaeology and anthropology to explain diversity and ethnic organization in the indigenous communities of Patagonia, both in the present and past. We believe that a critical review of the main assumptions from all these disciplines will allow us to observe and identify patterns emerging from the historical record of the expression of Patagonian social variability. Likewise, we suggest a new way of exploring the archaeological record rooted in critical theory.

  16. Registro de Moridae (Teleostei: Gadiformes en la Formación Chenque (Oligoceno Tardío-Mioceno Temprano de la provincia de Chubut, Argentina Record of Moridae (Teleostei: Gadiformes from the Chenque Formation (Late Oligocene - Early Miocene from the Chubut province, Argentina

    Directory of Open Access Journals (Sweden)

    Sergio Bogan

    2011-12-01

    Full Text Available En el presente trabajo se describen restos de un especimen relativamente completo perteneciente a la familia Moridae. Dicho ejemplar ha sido colectado en sedimentos referibles a la Formación Chenque (Oligoceno-Mioceno de la provincia de Chubut, Argentina. Este material constituye el primer registro fósil concreto de un Gadiformes para Argentina y los primeros materiales óseos fósiles registrados para Moridae. La morfología de los ejemplares sugiere afinidades con los géneros Physiculus y Salilota. La presencia de Moridae en el Mioceno Temprano de Patagonia y Nueva Zelanda se encuentra de acuerdo con hipótesis previas que indican conexiones marítimas transantárticas entre ambas regiones geográficas durante el Oligoceno Tardío - Mioceno Temprano.A nearly complete specimen belonging to the family Moridae is described in this paper. The material has been collected in outcrops referable to the Chenque Formation (Oligocene-Miocene from the Chubut province, Argentina. The specimen constitutes the first fossil record for the Gadiformes in Argentina and one of the first osteological occurrences for Moridae. The morphology of the specimen suggests affinities with the genera Physiculus and Salilota. The presence of Moridae in the Early Miocene of Patagonia and New Zealand is in agreement with previous hypotheses suggesting marine transantarctic connections between both landmasses during Late Oligocene - Early Miocene times.

  17. Preandean geological configuration of the eastern North Patagonian Massif, Argentina

    Directory of Open Access Journals (Sweden)

    Daniel A. Gregori

    2013-11-01

    Full Text Available The Preandean geological configuration of the eastern North Patagonian Massif is established through the use of geological and geophysical analysis. The positive gravity anomalies located near the Atlantic coast are due to 535 and 540 Ma old rocks belonging to the Pampean Orogeny (Precambrian–middle Cambrian, which are widely recognized in central and northern Argentina. The Famatinian Cycle (Ordovician–Devonian is represented by a Silurian–Devonian marine basin equivalent to those of eastern-central Argentina and South Africa, and which was deformed at the end of the Devonian by an ∼E–W to WNW–ESE compressional event, part of the Famatinian Orogeny. Containing strong gravity gradients, the NW–SE belt is coincident with fault zones which were originated during the Gondwanide Orogeny. This event also produced NW–SE overthrusting of the Silurian–Devonian sequences and strike-slip faults that displaced blocks in the same direction. This deformation event belongs to the Gondwanide Orogeny that includes movements related to a counterclockwise rotation of blocks in northern Patagonia. The strong negative anomalies located in the western part of the area stem from the presence of rocks of the Jurassic Cañadón Asfalto basin interbedded in the Marifil Complex. These volcaniclastic sequences show mild deformation of accommodation zones in a pre-Jurassic paleorelief.

  18. Patagonia, de margen exótico a periferia turística. Una mirada sobre un área natural protegida de frontera

    Directory of Open Access Journals (Sweden)

    Paula Gabriela Núñez

    2012-01-01

    Full Text Available Durante la primera mitad del siglo XX la creación de los Parques Nacionales en la Argentina, ubicados en espacios periféricos de frontera, respondió a diferentes lógicas en una organización territorial previa del país. Para analizar el impacto e infl uencia de estas Áreas Naturales Protegidas (ANP se consideró como caso de estudio el Parque Nacional Nahuel Huapi (Patagonia Andina, Argentina. Se concluyó que el ordenamiento territorial centralizado de la Nación se consolidó, en el Nahuel Huapi, a través de la institucionalización de un Área Natural Protegida. Asimismo, el análisis de este proceso permitió identifi car diferentes enfoques desde los cuales se pensó el desarrollo local y el turismo a lo largo del tiempo, afectando el modo de concebir las ANP periféricas.

  19. Study of UV cloud modification factors in Southern Patagonia

    Science.gov (United States)

    Wolfram, Elian A.; Orte, Facundo; Salvador, Jacobo; Quiroga, Jonathan; D'Elia, Raúl; Antón, Manuel; Alados-Arboledas, Lucas; Quel, Eduardo

    2017-02-01

    Anthropogenic perturbation of the ozone layer has induced change in the amount of UV radiation that reaches the Earth's surface, mainly through the Antarctic ozone hole, making the ozone and ultraviolet (UV) radiation two important issues in the study of Earth atmosphere in the scientific community. Also the clouds have been identified as the main modulator of UV amount in short time scales and produce the main source of uncertainty in the projection of surface UV level as consequence of projected ozone recovery. While clouds can decrease direct radiation, they can produce an increase in the diffuse component, and as consequence the surface UV radiation may be higher than an equivalent clear sky scenario for several minutes. In particular this situation can be important when low ozone column and partially cloud cover skies happen simultaneously. These situations happen frequently in southern Patagonia, where the CEILAP Lidar Division has established the Atmospheric Observatory of Southern Patagonia, an atmospheric remote sensing site near the city of Río Gallegos (51°55'S, 69°14'W). In this paper, the impact of clouds over the UV radiation is investigated by the use of ground based measurements from the passive remote sensing instruments operating at this site, mainly of broad and moderate narrow band filter radiometers. We analyzed the UV Index obtained from a multiband filter radiometer GUV-541 (UVI) [Biospherical Inc.] installed in the Observatorio Atmosférico de la Patagonia Austral, Río Gallegos, since 2005. Cloud modification factors (CMF, ratio between the measured UV radiation in a cloudy sky and the simulated radiation under cloud-free conditions) are evaluated for the study site. The database used in this work covers the period 2005-2012 for spring and summer seasons, when the ozone hole can affect these subpolar regions. CMF higher than 1 are found during spring and summer time, when lower total ozone columns, higher solar elevations and high cloud

  20. Airborne laser altimetry survey of Glaciar Tyndall, Patagonia

    DEFF Research Database (Denmark)

    Keller, K.; Casassa, G.; Rivera, A.

    2007-01-01

    flown over the ablation area of Glaciar Tyndall, with 5 longitudinal tracks with a mean swath width of 300 m, which results in a point spacing of approximately 2 m both along and across track. A digital elevation model (DEM) generated using the laser altimetry data was compared with a DEM produced from......The first airborne laser altimetry measurements of a glacier in South America are presented. Data were collected in November of 2001 over Glaciar Tyndall, Torres del Paine National Park, Chilean Patagonia, onboard a Twin Otter airplane of the Chilean Air Force. A laser scanner with a rotating...... polygon-mirror system together with an Inertial Navigation System (INS) were fixed to the floor of the aircraft, and used in combination with two dual-frequency GPS receivers. Together, the laser-INS-GPS system had a nominal accuracy of 30 cm after data processing. On November 23rd, a total of 235 km were...

  1. Splendid and Seldom Isolated: The Paleobiogeography of Patagonia

    Science.gov (United States)

    Wilf, Peter; Cúneo, N. Rubén; Escapa, Ignacio H.; Pol, Diego; Woodburne, Michael O.

    2013-05-01

    The idea that South America was an island continent over most of the Cenozoic, during which its unusual mammalian faunas evolved in isolation, is outstandingly influential in biogeography. Although large numbers of recent fossil discoveries and related advances require that the original isolation concept be significantly modified, it is still repeated in much current literature. The persistence of the idea inspired us to present here an integrated paleobiogeographic account of mammals, reptiles, and plants from the Jurassic to the Paleogene of Patagonia, which has by far the richest fossil record on the continent. All three groups show distribution patterns that are broadly consistent with South America's long separation history, first from Laurasia by the Late Jurassic, then from Africa and India-Madagascar during the late Early Cretaceous, and finally from Antarctica and Australia during the early-middle Eocene, after which “isolation” finally commenced. We highlight areas of promising future research and provide an updated view of South American isolation.

  2. Quantifying mass balance processes on the Southern Patagonia Icefield

    DEFF Research Database (Denmark)

    Schaefer, M.; Machguth, Horst; Falvey, M.

    2015-01-01

    measured accumulation of snow of up to 15.4m w.e. yr(-1) (meters water equivalent per year) as well as the high measured ablation of up to 11m w.e. yr(-1) is reproduced by the model. The overall modeled surface mass balance was positive and increasing during 1975-2011. Subtracting the surface mass balance......We present surface mass balance simulations of the Southern Patagonia Icefield (SPI) driven by downscaled reanalysis data. The simulations were evaluated and interpreted using geodetic mass balances, measured point balances and a complete velocity field of the icefield for spring 2004. The high...... from geodetic balances, calving fluxes were inferred. Mass losses of the SPI due to calving were strongly increasing from 1975-2000 to 2000-2011 and higher than losses due to surface melt. Calving fluxes were inferred for the individual glacier catchments and compared to fluxes estimated from velocity...

  3. Response of pumas (Puma concolor) to migration of their primary prey in Patagonia.

    Science.gov (United States)

    Gelin, Maria L; Branch, Lyn C; Thornton, Daniel H; Novaro, Andrés J; Gould, Matthew J; Caragiulo, Anthony

    2017-01-01

    Large-scale ungulate migrations result in changes in prey availability for top predators and, as a consequence, can alter predator behavior. Migration may include entire populations of prey species, but often prey populations exhibit partial migration with some individuals remaining resident and others migrating. Interactions of migratory prey and predators have been documented in North America and some other parts of the world, but are poorly studied in South America. We examined the response of pumas (Puma concolor) to seasonal migration of guanacos (Lama guanicoe) in La Payunia Reserve in northern Patagonia Argentina, which is the site of the longest known ungulate migration in South America. More than 15,000 guanacos migrate seasonally in this landscape, and some guanacos also are resident year-round. We hypothesized that pumas would respond to the guanaco migration by consuming more alternative prey rather than migrating with guanacos because of the territoriality of pumas and availability of alternative prey throughout the year at this site. To determine whether pumas moved seasonally with the guanacos, we conducted camera trapping in the summer and winter range of guanacos across both seasons and estimated density of pumas with spatial mark-resight (SMR) models. Also, we analyzed puma scats to assess changes in prey consumption in response to guanaco migration. Density estimates of pumas did not change significantly in the winter and summer range of guanacos when guanacos migrated to and from these areas, indicating that pumas do not follow the migration of guanacos. Pumas also did not consume more alternative native prey or livestock when guanaco availability was lower, but rather fed primarily on guanacos and some alternative prey during all seasons. Alternative prey were most common in the diet during summer when guanacos also were abundant on the summer range. The response of pumas to the migration of guanacos differs from sites in the western North

  4. Family medicine in Argentina

    Directory of Open Access Journals (Sweden)

    María Susana Bresca

    2013-05-01

    Full Text Available In Argentina, family medicine begins to appear in the sixties. It has followed along with the movement in favour of the specialty in Latin America and its existence in important areas is strongly related to men and women who have defended and promoted the specialty. It is present in many Ministry of Health programs; however, its development has depended and still depends on each jurisdiction and upon the coordination between the subsystems and political regions. The professional associations that bring together general practitioners and family doctors in Argentina.FAMG (General Medicine Federation of Argentina and FAMFYG (Argentina Federation of Family and General Medicine, have consolidated healthcare teams, elevated the scientific level of both family doctors in training as well as already certified practitioners, and have become acknowledged entities that certify the specialty and accreditation of teaching centers. Insertion in universities, provinces and private providers still poses challenges.

  5. Patagonia, Land of Nomads: A Glance at a Territory Shaped by Displacement

    Directory of Open Access Journals (Sweden)

    Pablo Chiuminatto

    2016-05-01

    Full Text Available By the end of the nineteenth century, as global voyages became popular, and transcontinental empires settled, remote corners of the third world such as Patagonia began to be explored and became the subject of European travel literatures. The opening of this region to the global scenario produced profound transformations in its territorial conformation, poetic imaginary, and local culture. As Patagonia became a land of travellers, local nomads which had inhabited this land for centuries became extinguished. The historical context of this re-shaping is conceptualised in literary theory through notions such as nomadism, elaborated by Gilles Deleuze and its aesthetical counterpart, geo-poetics, by Kenneth White. The travel literature about Patagonia, such as that produced by Charles Darwin, Lady Florence Dixie, and Bruce Chatwin, depicts the difficulties these travellers faced in trying to endow their writings of adequate descriptions and images. Instead, they recurred to images from their homeland, and thus created an imaginary of Patagonia through displacement: their own, and that of images brought by themselves to this land. When Chilean poets like Gabriela Mistral and Pablo Neruda begun to write about Patagonia, they found it already populated by strange images, shaped indeed, by nomads, travellers and dis-located identities.

  6. Mapuche Ancestral Recovery of Land. The Lof Inkaial WalMapu Meu case of study (Nahuel Huapí National Park, Río Negro, Argentina

    Directory of Open Access Journals (Sweden)

    Guido Galafassi

    2012-07-01

    Full Text Available The aim of this paper is to present and analyze the case of a recent social mobilization which involved a Mapuche community in the southern region of Argentina, known as Patagonia. An “ancestral recovery of land” was claimed to be the objective of the action. Several conflicts emerged due to the fact that the land in conflict is part of the Nahuel Huapi National Park, which implied a straightforward questioning of the National State rights over territory. Apart from that, the recovery process was strongly rejected by local residents. This brought about a new conflict that required the local government's mediation.

  7. Helosis (Balanophoraceae en Argentina Helosis (Balanophoraceae in Argentina

    Directory of Open Access Journals (Sweden)

    José Luis Fontana

    2006-07-01

    Full Text Available Se cita por primera vez para Argentina Helosis cayennensis (Swartz Sprengel var. cayennensis en base a colecciones hechas por los autores en la Isla argentina de Apipé Grande, Ituzaingó, provincia de Corrientes. Se describe e ilustra la especie, el desarrollo de la planta y su estado de conservación. Esta cita de Helosis corresponde a un género nuevo para la flora argentina.Helosis cayennensis var. cayennensis is reported for the first time for Argentina. The species is described and ilustrated. Developement and ecology are also given. Helosis is also a new generic record for Argentina.

  8. OPTICAL FLOW APPLIED TO TIME-LAPSE IMAGE SERIES TO ESTIMATE GLACIER MOTION IN THE SOUTHERN PATAGONIA ICE FIELD

    Directory of Open Access Journals (Sweden)

    E. Lannutti

    2016-06-01

    Full Text Available In this work, we assessed the feasibility of using optical flow to obtain the motion estimation of a glacier. In general, former investigations used to detect glacier changes involve solutions that require repeated observations which are many times based on extensive field work. Taking into account glaciers are usually located in geographically complex and hard to access areas, deploying time-lapse imaging sensors, optical flow may provide an efficient solution at good spatial and temporal resolution to describe mass motion. Several studies in computer vision and image processing community have used this method to detect large displacements. Therefore, we carried out a test of the proposed Large Displacement Optical Flow method at the Viedma Glacier, located at South Patagonia Icefield, Argentina. We collected monoscopic terrestrial time-lapse imagery, acquired by a calibrated camera at every 24 hour from April 2014 until April 2015. A filter based on temporal correlation and RGB color discretization between the images was applied to minimize errors related to changes in lighting, shadows, clouds and snow. This selection allowed discarding images that do not follow a sequence of similarity. Our results show a flow field in the direction of the glacier movement with acceleration in the terminus. We analyzed the errors between image pairs, and the matching generally appears to be adequate, although some areas show random gross errors related to the presence of changes in lighting. The proposed technique allowed the determination of glacier motion during one year, providing accurate and reliable motion data for subsequent analysis.

  9. Diagnóstico de pseudotuberculosis en ovinos patagónicos Diagnosis of caseous lymphadenitis in sheep from Patagonia

    Directory of Open Access Journals (Sweden)

    S. Estevao Belchior

    2007-03-01

    Full Text Available La linfadenitis caseosa (LAC es una enfermedad bacteriana supurativa crónica que afecta a ovinos. El agente etiológico es Corynebacterium pseudotuberculosis. El diagnóstico diferencial con otras afecciones que presentan manifestaciones clínicas similares sólo puede hacerse sobre la base del aislamiento y la identificación del agente etiológico. El objetivo de este trabajo fue caracterizar metabólica y genéticamente al agente causal de abscesos granulomatosos observados en ovinos en la región patagónica. En las muestras, se observó un contenido caseoso rodeado de una membrana fibrosa, y en el examen histopatológico, un centro de necrosis caseosa rodeado por células epitelioides, linfocitos y polinucleares. Mediante estudios microscópicos, bacteriológicos y moleculares fue confirmada la infección causada por C. pseudotuberculosis biovar ovis.Caseous lymphadenitis (CLA is a chronic bacterial, infectious and contagious disease caused by Corynebacterium pseudotuberculosis. It affects sheep and results in abscesses of the lymph nodes in subcutaneous tissue, as well as in internal organs such as lungs, liver and kidneys. Differential diagnosis of the disease is based on the isolation and biochemical identification of the etiological agent. The purpose of this study was to characterize the bacteria isolated from typical CLA lesions in sheep from Patagonia, Argentina, at metabolic and genetic levels. Macroscopic observations show a fibrous membrane containing caseous necrotic tissue. Histopathological analysis shows an eosinophilic necrotic area surrounded by epitheloid cells and polymorphonuclear infiltration. Other analyses performed such as microscopic observations, in vitro culture, biochemical tests and 16s rDNA sequencing confirmed diagnosis of caseous lymphadenitis due to C. pseudotuberculosis.

  10. Source and trophic transfer of mercury in plankton from an ultraoligotrophic lacustrine system (Lake Nahuel Huapi, North Patagonia).

    Science.gov (United States)

    Rizzo, Andrea; Arcagni, Marina; Campbell, Linda; Koron, Neža; Pavlin, Majda; Arribére, María A; Horvat, Milena; Guevara, Sergio Ribeiro

    2014-09-01

    The incorporation and trophic transfer of total and methyl mercury (THg, MeHg) were examined in three size classes of plankton (10-53, 53-200, and >200 μm size range) and a small planktivorous fish, Galaxias maculatus, from the large multi-branched Lake Nahuel Huapi (North Patagonia, Argentina). Three sites representing a large range of lake benthic-pelagic structures (based on depth and shoreline characteristics) and precipitation regimes were sampled. Nitrogen and carbon stable isotopes (δ(15)N, δ(13)C) were analyzed to assess Hg trophodynamics. Selenium concentrations were determined together with THg in order to consider its potential effect on Hg trophodynamics. High THg concentrations (0.1-255 µg g(-1) dry weight (DW)) were measured in plankton, largely in inorganic form (MeHg: 3-29 ng g(-1) DW, 0.02-7% of THg, in the two larger size classes). A trend of increasing THg concentrations, varying in two to three orders of magnitude, with decreasing plankton size was associated with precipitation measured prior to each sampling event. Passive adsorption of dissolved Hg(2+) from wet deposition and runoff is considered to be the principal Hg uptake mechanism at the base of the pelagic food web. Despite the initially high THg uptake in the smaller plankton classes, the transfer to G. maculatus, and consequently to the entire food web, is likely limited due to low proportion of MeHg to THg in plankton. Furthermore, evidence of G. maculatus with benthic feeding habits having higher impact on MeHg trophic transfer compared to the same species with more pelagic (e.g., zooplankton) feeding habits, was observed. Although there is a high THg uptake in plankton, limited amounts are incorporated in the entire food web from the pelagic compartment.

  11. Composting of fish offal and biosolids in northwestern Patagonia.

    Science.gov (United States)

    Laos, F; Mazzarino, M J; Walter, I; Roselli, L; Satti, P; Moyano, S

    2002-02-01

    Composting of fish processing wastes and biosolids with wood by-products and yard trimmings was conducted during the summer of 1996 and winter of 1997 in NW Patagonia using: (i) static piles for fish offal and (ii) turning piles for biosolids. Fish offal was mixed with sawdust + wood shavings (FOC) at 3:1 ratio by weight and biosolids with wood shavings (BCw) and yard trimmings (BCt) at 1:1 ratio by volume. Samples were taken at six dates during the composting period and analyzed to determine the factors that predict compost maturity. Composting of biosolids was affected by the type of bulking agent during winter. Thermophilic temperatures > or = 55 degrees C were sustained long enough to satisfy the USEPA requirements for processes to further reduce pathogens (PFRP) in FOC and BCt, and for processes to significantly reduce pathogens (PSRP) in summer BCw, while in winter BCw temperatures were lower than those recommended for effective pathogen reduction. However, coliform fecal content in all BC treatments was less than 10 most probable number (MPN) g(-1) dry sample at the end of the process. The ratio of water soluble carbon (WSC) to total nitrogen (TN) appeared to be a more adequate index to predict compost maturity than the ratio of total organic carbon to nitrogen.

  12. NEW DISTRIBUTION RECORD OF Cryptotermes brevis (ISOPTERA, KALOTERMITIDAE) IN ARGENTINA

    OpenAIRE

    JUAN MANUEL CORONEL; ENRIQUE LAFFONT; CELINA GODOY; CLARA ETCHEVERRY; MARCELA OBREGÓN

    2014-01-01

     The first record of the West Indian drywood termite Cryptotermes brevis  (Walker, 1853) in the city of Corrientes (Argentina) is reported. Several C. brevis  colonies were detected inside a local deposit, from wooden crates used for carrying fresh fruits. The observed damage consisted of small rounded holes, partially hollowed wood pieces and presence of debris. The importance of weather factors and the type of material of vegetable and fruit containers in the colonization and dispersion of ...

  13. Peasant territoriality in the South of Argentina. Productive and labour changes as forms of resistance

    Directory of Open Access Journals (Sweden)

    Mónica Bendini

    2014-03-01

    Full Text Available In a context of territorial expansion of capital and social changes in rural life, the article addresses the issue of the persistence of peasant producers in northern Patagonia (Argentina and the development of various adaptive strategies as a form of resistance expulsion as producers. The changes are researched not only in households but also in the areas of life and work of those producers who call themselves "crianceros" in two regions of extensive livestock export oriented, wool and mohair hair. The cases show that the territorial expansion of capital involves social dynamics that go beyond productive and institutional transformations. Family strategies are more complex and also generate changes in other levels of rurality, in the mobility, in the habitat, in the activities of the countryside and towns, in the horizons of rural life. 

  14. Difilobotriosis humana: Un caso en área no endémica de la Argentina

    Directory of Open Access Journals (Sweden)

    Diego E. Cargnelutti

    2012-02-01

    Full Text Available La difilobotriosis es una parasitosis intestinal causada por la infección de cestodos del genero Diphyllobothrium. En la Argentina, la Patagonia Andina es considerada una zona endémica para esta parasitosis. La infección por Diphyllobothrium latum no ha sido previamente notificada en la provincia de Mendoza; en este trabajo comunicamos un caso de esta parasitosis que fue confirmada por el análisis de las características morfológicas de los huevos eliminados con la materia fecal de un paciente infectado. Se destaca la necesidad de información y capacitación de los profesionales de la salud en el diagnóstico y tratamiento de parasitosis no endémicas.

  15. New fossil record of a Jurassic pterosaur from Neuquen Basin, Vaca Muerta Formation, Argentina

    Science.gov (United States)

    Codorniú, Laura; Garrido, Alberto

    2013-12-01

    Discoveries of Jurassic pterosaurs in the Southern Hemisphere are extremely unusual. In Argentina, pterosaurs from the Upper Jurassic (Tithonian) have only been found in the Northwest of Patagonia (Neuquén Basin). These come from marine deposits and three specimens have been discovered up to the present. In this paper, we report a new finding from the Neuquén Basin. This material is identified as a tibiotarsus, which probably belonged to an osteologically adult individual and represents a new species of a pterodactyloid pterosaur of medium size. This discovery provides new evidence that at least two different species of pterodactyloid pterosaurs may have coexisted in Los Catutos Member, Vaca Muerta Formation, from the shallow marine deposits of the Neuquén Basin.

  16. Nuevas citas de Coleoptera para la Argentina (Carabidae, Lucanidae, Scarabaeidae y Tenebrionidae New records of Coleoptera for Argentina (Carabidae, Lucanidae, Scarabeidae and Tenebrionidae

    Directory of Open Access Journals (Sweden)

    Sergio Roig-Juñent

    2004-12-01

    Full Text Available En enero de 2003, se realizó un viaje de campaña con el fin de recolectar materiales en áreas poco prospectadas de la estepa patagónica de Mendoza y Neuquén, Argentina, así como en ambientes de bosques de Nothofagus en la provincia de Neuquén. Las recolecciones se realizaron en forma manual, usando trampas con cebo y trampas de luz de mercurio. El material recolectado permite citar por primera vez para la Argentina los géneros Nothobroscus Roig-Juñent & Ball y Mimophilorizus Mateu (Carabidae, Callyntra Solier y Homocyrtus Reitter (Tenebrionidae. Además, se citan por primera vez para la Argentina las especies Cnemalobus sulciferus Philippi (Carabidae, Allidiostoma landbecki (Philippi, Macrodactylus chilensis Solier y Brachysternus marginatus (Germain (Scarabeidae y Pycnosiphorus philippii (Westwood (Lucanidae. Se provee una breve descripción de los ambientes en donde estas especies fueron encontradas.A short expedition to northern Patagonia was made in January 2003. The main goal of the trip was to survey the diversity of some families of Coleoptera in the insufficient explored steppes in Mendoza and Neuquén provinces, Argentina and Nothofagus forests of Neuquén province. The techniques included manual collection and the use of different kinds of traps, such as with bite or artificial light of mercury. The study of the material revealed four new genera records and four new species records for the country: Nothobroscus Roig-Juñent & Ball and Mimophilorizus Mateu (Carabidae, Callyntra Solier and Homocyrtus Reitter (Tenebrionidae are the new genus records. Cnemalobus sulciferus Philippi (Carabidae, Allidiostoma landbecki (Philippi, Macrodactylus chilensis Solier, and Brachysternus marginatus (Germain (Scarabeidae, and Pycnosiphorus philippii (Westwood (Lucanidae are the new species records. A brief description of the habitats where the species were collected is provided.

  17. IDRC in Argentina

    International Development Research Centre (IDRC) Digital Library (Canada)

    improve their computer skills. The research has created the conditions for future economic activity and jobs, espe- cially for youth in rural communities. Research ... researchers took up key leadership posts, including foreign affairs, international cooperation, and planning. Urban gardens. Argentina's economic crisis of 2000-.

  18. Mathematics Education in Argentina

    Science.gov (United States)

    Varsavsky, Cristina; Anaya, Marta

    2009-01-01

    This article gives an overview of the state of mathematics education in Argentina across all levels, in the regional and world contexts. Statistics are drawn from Mercosur and UNESCO data bases, World Education Indicators and various national time-series government reports. Mathematics results in national testing programmes, Programme for…

  19. Gifted Education in Argentina

    Science.gov (United States)

    Irueste, Paula

    2017-01-01

    In this article, we review the advancement of gifted education in Argentina which has been scarce and discontinuous, particularly, in the public sphere. About the primary conception of giftedness and/or talent, we mention the obsolete struggle between those who only consider a high intellectual coefficient (IQ) versus a more comprehensive…

  20. Tidal power in Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Aisiks, E.G.

    1993-03-01

    This presentation describes the tidal power potential of Argentina and the current status of its utilization. The topics of the presentation include tidal power potential, electric production of the region and the Argentine share of production and consumption, conventional hydroelectric potential, economic feasibility of tidal power production, and the general design and feasibility of a tidal power plant planned for the San Jose Gulf.

  1. Oceanographic Processes in Chilean Fjords of Patagonia: From small to large-scale studies

    Science.gov (United States)

    Iriarte, José L.; Pantoja, Silvio; Daneri, Giovanni

    2014-12-01

    Subantarctic ecosystems, such as the inner shelf of southern Chile (41-55°S), are characterized by a complex system of fjords, channels, gulf, estuaries, bays, and are affected by physical regimes that may strongly modulate biological productivity. Rhythms and rates of primary production in these highly fluctuating fjord environments depend to a large extent on the timing and magnitude of nutrient supply and light availability for primary producers. In such complex fjord systems, the interaction between oceanic waters and freshwater from multiple sources (e.g., rivers, surface and groundwater runoff, snow/glacier melting, and precipitation) produces strong vertical and horizontal gradients in salinity, density, organic and inorganic nutrient ratios and light availability (Pickard, 1971; Dávila et al., 2002; Silva and Palma 2006; Jacob et al., 2014). The vertical structure of the water column (stratified/mixed), modulated by the seasonal and inter-annual changes of the pycnocline may affect biomass and composition of pelagic and benthic assemblages, and ultimately spatial and temporal patterns of carbon fluxes (the 'Biological Pump'), and biogeochemical balances in this large region. In addition, the region is particularly vulnerable to climate change and anthropogenic influences (Iriarte et al., 2010). Remote and large-scale climatic-oceanographic phenomena (e.g., ENSO and Southern Annular Mode) and global climate trends may alter freshwater discharge of large rivers such as the Puelo and Palena, as has also been suggested for the Baker River located between Patagonian Ice fields and other northern fjords shown by paleo-oceanographic (Sepúlveda et al., 2009; Rebolledo et al., 2011) and dendrochronological studies (Lara et al., 2008). Although changes in climate are expected to alter the regional atmospheric forcing such as the West Wind Drift (Quintana and Aceituno, 2012; Garreaud et al., 2013) and the local ocean circulation in this region, including the

  2. Organic carbon in glacial fjords of Chilean Patagonia

    Science.gov (United States)

    Pantoja, Silvio; Gutiérrez, Marcelo; Tapia, Fabián; Abarzúa, Leslie; Daneri, Giovanni; Reid, Brian; Díez, Beatriz

    2016-04-01

    The Southern Ice Field in Chilean Patagonia is the largest (13,000 km2) temperate ice mass in the Southern hemisphere, yearly transporting ca. 40 km3 of freshwater to fjords. This volume of fresh and cold water likely affects adjacent marine ecosystems by changing circulation, productivity, food web dynamics, and the abundance and distribution of planktonic and benthic organisms. We hypothesize that freshwater-driven availability of inorganic nutrient and transport of organic and inorganic suspended matter, as well as microbes, become a controlling factor for productivity in the fjord associated with the Baker river and Jorge Montt glacier. Both appear to be sources of silicic acid, but not of nitrate and particulate organic carbon, especially during summer, when surface PAR and glacier thawing are maximal. In contrast to Baker River, the Jorge Montt glacier is also a source of dissolved organic carbon towards a proglacial fjord and the Baker Channel, indicating that a thorough chemical description of sources (tidewater glacier and glacial river) is needed. Nitrate in fiord waters reaches ca. 15 μM at 25 m depth with no evidence of mixing up during summer. Stable isotope composition of particulate organic nitrogen reaches values as low as 3 per mil in low-salinity waters near both glacier and river. Nitrogen fixation could be depleting δ15N in organic matter, as suggested by the detection at surface waters of nif H genes belonging to diazotrophs near the Montt glacier. As diazotrophs have also been detected in other cold marine waters (e.g. Baltic Sea, Arctic Ocean) as well as glaciers and polar terrestrial waters, there is certainly a potential for both marine and freshwater microbes to contribute and have a significant impact on the Patagonian N and C budgets. Assessing the impact of freshwater on C and N fluxes and the microbial community structure in Patagonian waters will allow understanding future scenarios of rapid glacier melting. This research was funded

  3. Deglacial palaeoclimate at Puerto del Hambre, subantarctic Patagonia, Chile

    Science.gov (United States)

    Heusser, Calvin J.; Heusser, Linda E.; Lowell, Thomas V.; Moreira M., Andrés; Moreira M., Simón

    2000-02-01

    The primary objective of this study is to further substantiate multistep climatic forcing of late-glacial vegetation in southern South America. A secondary objective is to establish the age of deglaciation in Estrecho de Magallanes-Bahía Inútil. Pollen assemblages at 2-cm intervals in a core of the mire at Puerto del Hambre (53°3621S, 70°5553W) provide the basis for reconstructing the vegetation and a detailed account of palaeoclimate in subantarctic Patagonia. Chronology over the 262-cm length of core is regulated by 20 AMS radiocarbon dates between 14 455 and 10 089 14C yr BP. Of 13 pollen assemblage zones, the earliest representing the Oldest Dryas chronozone (14 455-13 000 14C yr BP) records impoverished steppe with decreasing frequencies and loss of southern beech (Nothofagus). Successive 100-yr-long episodes of grass/herbs and of heath (Empetrum/Ericaceae) before 14 000 14C yr BP infer deglacial successional communities under a climate of increased continentality prior to the establishment of grass-dominated steppe. The Bølling-Allerød (13 000-11 000 14C yr BP) is characterised by mesic grassland under moderating climate that with abrupt change to heath dominance after 12 000 14C yr BP was warmer and not as humid. At the time of the Younger Dryas (11 000-10 000 14C yr BP), grass steppe expanded with a return of colder, more humid climate. Later, with gradual warming, communities were invaded by southern beech. The Puerto del Hambre record parallels multistep, deglacial palaeoclimatic sequences reported elsewhere in the Southern Andes and at Taylor Dome in Antarctica. Deglaciation of Estrecho de Magallanes-Bahía Inútil is dated close to 14 455 14C yr BP, invalidating earlier dates of between 15 800 and 16 590 14C yr BP.

  4. Firewood Resource Management in Different Landscapes in NW Patagonia

    Directory of Open Access Journals (Sweden)

    Daniela V. Morales

    2017-09-01

    Full Text Available Ecosystems, their components, processes and functions are all subject to management by human populations, with the purpose of adapting the environments to make them more habitable and ensuring the availability and continuity of subsistence resources. Although a lot of work has been carried out on resources of alimentary or medicinal interest, little has been done on associating processes of domestication with firewood extraction, a practice considered to be destructive of the environment. In the arid steppe of NW Patagonia, inhabited and managed for different purposes for a long time by Mapuche-Tehuelche communities, the gathering of combustible plant species has up to the present time played a crucial role in cooking and heating, and work is required to achieve sustainability of this resource. In this study we evaluate whether environments with less landscape domestication are more intensively used for firewood gathering. Using an ethnobiological approach, information was obtained through participant observation, interviews and free listing. The data were examined using both qualitative and quantitative approaches. Twenty-eight firewood species are gathered, both native (75% and exotic (25%. The supply of firewood mainly depends on gathering from the domesticated (10 species, semi-domesticated (17 species and low human intervention landscapes (17 species. In contrast to our hypothesis, average use intensity is similar in all these landscapes despite their different levels of domestication. That is, the different areas are taken advantage of in a complementary manner in order to satisfy the domestic demand for firewood. Neither do biogeographic origin or utilitarian versatility of collected plants vary significantly between the different landscape levels of domestication. Our results show that human landscape domestication for the provision of firewood seems to be a socio-cultural resilient practice, and shed new light on the role of culture in

  5. Aeolian sediment mass fluxes on a sandy soil in Central Patagonia

    NARCIS (Netherlands)

    Sterk, G.; Parigiani, J.; Cittadini, E.; Peters, P.; Scholberg, J.M.S.; Peri, P.

    2012-01-01

    The climate of Patagonia is semi-arid and characterised by frequent strong winds. Wind erosion is potentially a serious soil degradation process that impacts long-term sustainability of local agricultural systems, but the conditions and the rates of wind erosion in this region have not been studied

  6. Aeolian sediment mass fluxes on a sandy soil in Central Patagonia

    NARCIS (Netherlands)

    Sterk, G.; Parigiani, J.; Cittadini, E.; Peters, P.; Scholberg, J.; Peri, P.

    2012-01-01

    The climate of Patagonia is semi-arid and characterised by frequent strong winds. Wind erosion is potentially a serious soil degradation process that impacts long-term sustainability of local agricultural systems, but the conditions and the rates of wind erosion in this region have not been

  7. Extreme precipitation and climate gradients in Patagonia revealed by high-resolution regional atmospheric climate modeling

    NARCIS (Netherlands)

    Lenaerts, J.T.M.|info:eu-repo/dai/nl/314850163; van den Broeke, M.R.|info:eu-repo/dai/nl/073765643; van Wessem, J.M.|info:eu-repo/dai/nl/413533085; van de Berg, W.J.|info:eu-repo/dai/nl/304831611; van Meijgaard, E.; van Ulft, L.H.; Schaefer, M.

    2014-01-01

    This study uses output of a high-resolution (5.5 km) regional atmospheric climate model to describe the present-day (1979–2012) climate of Patagonia, with a particular focus on the surface mass balance (SMB) of the Patagonian ice fields. Through a comparison with available in situ observations, it

  8. Seasonal determination of trace and ultra-trace content in Macrocystis pyrifera from San Jorge Gulf (Patagonia) by Total Reflection X-ray Fluorescence

    Science.gov (United States)

    Salomone, Vanesa N.; Riera, Marina; Cerchietti, Luciana; Custo, Graciela; Muniain, Claudia

    2017-05-01

    Seaweed have a great capacity to accumulate heavy metals in their tissues. The chemical characterization of seaweed is important due to their use in environmental monitoring and human or animal food. The aim of the present study was to evaluate the multi-elemental composition of seaweed from San Jorge Gulf (Patagonia, Argentina) by Total Reflection X-ray Fluorescence (TXRF). The elements As, Br, Cu, Cr, Fe, Mn, Ni, Pb, Rb, Sr, V and Zn were seasonally analyzed and quantified in blades of Macrocystis pyrifera. TXRF showed to be a suitable technique for simultaneous multi-element analysis in this kind of samples. The results revealed seasonal variations in the chemical content for some elements; arsenic content was maximum in summer and autumn, iron concentration increased to the winter and zinc concentration was maximum in autumn. The sum of principal micronutrients (Fe + Zn + Mn + Cu) varied between 114 and 171 mg k- 1 g dw. The total As concentration ranged between 36 and 66 mg kg- 1. Lead, nickel and copper were not detected.

  9. LA PATAGONIA COMO TERRITORIO EN DISPUTA: TENSIONES ENTRE EL ESTADO, LA IGLESIA Y LA CONGREGACIÓN SALESIANA POR EL ESPACIO MISIONERO

    Directory of Open Access Journals (Sweden)

    María Nicoletti

    2012-06-01

    Full Text Available La Patagonia fue el primer territorio salesiano “ad gentes”. La creación de su administración bajo la figura de un Vicariato y Prefectura apostólica de parte de la Congregación Salesiana y el Colegio de Propaganda Fide, trajo aparejados numerosos conflictos con las Iglesias Argentina y Chilena y con ambos Estados nacionales. Estos conflictos, en el marco histórico de la construcción de las naciones del siglo XIX y principios del siglo XX, fueron acompañados por los planes de evangelización que la Congregación salesiana había formulado para los pueblos originarios. Bajo la gestión y dirección de los dos primeros rectores mayores de la Congregación, Don Bosco y Don Rua, se resolvieron los problemas con las Iglesias y Estados de ambas naciones, cargados de tensiones en la construcción del territorio de evangelización considerado según cada institución como “terra nullius”, “territorio salesiano” o “territorio nacional y diocesano”.

  10. Estado actual del conocimiento de la familia Ceratopogonidae en la Patagonia (Diptera: Nematocera Current knowledge of the family Ceratopogonidae in Patagonia (Diptera: Nematocera

    Directory of Open Access Journals (Sweden)

    Gustavo R. Spinelli

    2009-06-01

    Full Text Available Ceratopogonidae incluye pequeños dípteros nematoceros que crían en hábitats acuáticos o semiacuáticos. Hasta los '80, el conocimiento de su taxonomía en la Patagonia se hallaba limitado a la contribución de los comienzos de los '30 de Ingram y Macfie, sobre la base de material capturado en 1926-27, en el área del Parque Nacional Nahuel Huapi y zonas vecinas de Chile. En los últimos 25 años, se pusieron en marcha diferentes proyectos, resultando la descripción o registro de numerosos taxones para la región. Si se contabilizan los datos publicados, 102 especies habitan en la Patagonia, de las cuales 86 (84,31% son endémicas para la región. Este alto porcentaje es evidente en los bosques de Nothofagus, con 71 especies endémicas de este bioma, nueve lo son de la estepa y seis presentan registros en bosque y estepa. Datos aún no publicados concuerdan con este esquema. Diecinueve géneros están representados en la Patagonia, diez de ellos con amplia distribución, tres de distribución transantártica y seis son endémicos para el área. Para la misma, se hallan publicadas las revisiones de Forcipomyia, Atrichopogon, Borkenthelea, Macrurohelea y Paradasyhelea; se han finalizado y aún no publicado aquellas de Dasyhelea y Palpomyia, está muy avanzada la de Stilobezzia y se prevé comenzar con las de Austrohelea, Austrosphaeromias, Physohelea y Bezzia. Se calcula que estos datos no divulgados contienen al menos 55 especies todavía no descriptas. Con respecto a los aspectos biogeográficos se pueden destacar estudios que tienden a establecer relaciones entre las áreas reconocidas en esquemas biogeográficos propuestos para la región andina.Ceratopogonidae includes small nematoceran Diptera which breed in aquatic and semiaquatic habitats. Until the 80´s its taxonomic knowledge in Patagonia was limited to the early 30´s contribution of Ingram and Macfie, from material collected in 1926-27 in the area of the Nahuel Huapi National

  11. Exploring the Diversity and Antimicrobial Potential of Marine Actinobacteria from the Comau Fjord in Northern Patagonia, Chile

    National Research Council Canada - National Science Library

    Undabarrena, Agustina; Beltrametti, Fabrizio; Claverías, Fernanda P; González, Myriam; Moore, Edward R B; Seeger, Michael; Cámara, Beatriz

    2016-01-01

    .... In this study, the diversity and biotechnological potential of Actinobacteria isolated from marine sediments within the Comau fjord, in Northern Chilean Patagonia, were assessed by culture-based approaches...

  12. El IDRC en Argentina

    International Development Research Centre (IDRC) Digital Library (Canada)

    las políticas de ciencia y tecnología. □ Adquisiciones gubernamentales más eficientes. Financiamiento: CA$1 673 800. Duración: 2009–2013. Beneficiario: Universidad Nacional de. San Martín, Argentina. En América Latina y el Caribe, las compras gubernamentales tienen un fuerte impacto económico, sobre todo en las ...

  13. de la sociedad argentina

    Directory of Open Access Journals (Sweden)

    Diego Galeano

    2007-01-01

    Full Text Available Este artículo trata sobre un período de la historia argentina en el cual la "mirada médica", a través de un grupo de prestigiosos intelectuales, se convirtió en una clave de interpretación de la sociedad argentina. El análisis gira en torno a la obra de uno de los médicos higienistas más influyentes, José María Ramos Mejía, deteniéndose especialmente en su libro más famoso: Las multitudes argentinas (1899. La hipótesis principal que recorre el texto es la siguiente: la medicalización de la sociedad, acentuada luego de las epidemias de cólera y fiebre amarilla de mediados del siglo XIX, ofreció a las elites públicas la posibilidad de construir dominios legítimos de intervención estatal. Intromisiones del Estado en la vida privada que, además de ser algo resistidas por la población, entraban en tensión con los principios teóricos del liberalismo que los propios miembros de la elite defendían.

  14. Primera cita de la especie Goniozus legneri (Hymenoptera: Bethylidae en el Alto Valle de Río Negro, Patagonia Argentina First record of the species Goniozus legneri Gordh in the Alto Valle de Río Negro, Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Silvina Garrido

    2005-07-01

    Full Text Available Se reporta por primera vez para la zona del Alto Valle de Río Negro, a Goniozus legneri Gordh, parasitando naturalmente larvas de Cydia pomonella (L, "carpocapsa", en montes comerciales de manzanos y nogales. Se comentan brevemente su hallazgo, características morfológicas, distribución, biología e influencia en las poblaciones de "carpocapsa".First record of Goniozus legneri Gordh, parasitizing larva of Cydia pomonella (L, "codlingh moth", in apple and walnut orchard from the Alto Valle de Río Negro. Discover, morphology, distribution, biology, and influence on the "codling moth" population are briefly commented.

  15. Impacto del pastoreo sobre picoplancton autotrófico en dos lagos andinos (Patagonia, Argentina con diferentes relaciones luz:nutrientes Grazing impact on autotrophic picoplankton in two south Andean lakes (Patagonia, Argentina with different light:nutrient ratios

    Directory of Open Access Journals (Sweden)

    ESTEBAN G. BALSEIRO

    2004-03-01

    Full Text Available Los lagos andino-patagónicos son ambientes con una alta relación luz:nutrientes. En estos lagos se ha descrito una red trófica particular constituida por grandes ciliados mixotróficos que comparten y compiten por recursos alimentarios con nanoflagelados y cladóceros. A través de experimentos de pastoreo se compararon las tasas de limpieza sobre picoplancton autotrófico de nanoflagelados; el ciliado Ophrydium naumanni y cladóceros de los lagos Moreno Oeste y Rivadavia. Estos lagos presentan diferencias significativas en cuanto a su relación luz:nutrientes y tienen también una composición de crustáceos del zooplancton diferente. En el lago Moreno Oeste, el metalimnion está incluido dentro de la zona eufótica, determinando un estrato iluminado en el que se desarrolla un máximo de clorofila en profundidad. En el lago Rivadavia, en cambio, los estratos iluminados están restringidos al epilimnion y no se observó ningún máximo de clorofila en profundidad. En el lago Moreno se observó que a 30 m de profundidad se producía un incremento en la proporción de la bacterivoría ejercida por el ciliado O. naumanni y el cladócero Ceriodaphnia dubia debido fundamentalmente a la distribución vertical de ambas especies. Por el contrario, las tasas de limpieza del conjunto de nanoflagelados, dominado por la especie mixótrofa Chrysochromulina parva, no presentaron cambios a lo largo de la columna de agua y fueron un orden de magnitud mayores que aquellas de O. naumanni y C. dubia. En el lago Rivadavia, las tasas de pastoreo de los nanoflagelados fueron menores y comparables con las obtenidas para O. naumanni y Daphnia cf. commutata. Las diferencias observadas en las tasas de limpieza de nanoflagelados probablemente reflejan un incremento de la fagotrofía donde la energía lumínica es alta en relación con el fósforo. De esta manera, en el lago Moreno Oeste, donde la luz no es limitante, el aumento observado en la bacterivoría de los protistas podría deberse a un mayor requerimiento de nutrientes limitantesAndean ultraoligotrophic lakes are environments with high light:nutrient ratios. In these lakes a particular planktonic food web has been noticed, constituted by large mixotrophic ciliates which share and compete for food resources with nanoflagellates and cladocerans. Clearance rates on autotrophic picoplankton of nanoflagellates, the ciliate Ophrydium naumanni and cladocerans were compared through grazing experiments in lakes Moreno Oeste and Rivadavia. The lakes exhibited significant differences in the light:nutrient ratio and had different crustacean and zooplankton compositions. In lake Moreno Oeste the metalimnion was included in the euphotic zone resulting in an illuminated layer where deep chlorophyll maxima developed. On the contrary, in lake Rivadavia the illuminated layers were restricted to the epilimnion and no deep chlorophyll maxima were observed. In lake Moreno Oeste, the contribution to total bacterivory of the ciliate O. naumanni and the cladoceran Ceriodaphnia dubia was observed to increase at 30 m depth, due mainly to the vertical distribution of both species. On the contrary, the grazing rates of the nanoflagellate assemblage, dominated by the mixotrophic Chrysochromulina parva, did not change along the water column and were considerably high (one order of magnitude higher than those obtained for O. naumanni and C. dubia. In lake Rivadavia, nanoflagellate grazing rates were lower and the relative impact of the nanoflagellate assemblage was comparable to those of O. naumanni and Daphnia cf .commutata. The observed difference in clearance rates of the nanoflagellate assemblage probably would reflect an increase in the phagotrophy where light energy is higher relative to phosphorus. In lake Moreno Oeste where light is not limiting, the observed increase of the phagotrophy by protists may be due to a higher requirement of limiting elements

  16. Studies on the reproductive dynamics of Pleoticus muelleri (Bate, 1888 (Crustacea, Decapoda, Solenoceridae of Patagonia, Argentina Estudios sobre la dinámica reproductiva del langostino Pleoticus muelleri (Bate, 1888 (Crustacea, Decapoda, Solenoceridae de Patagonia, Argentina

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    Mónica Fernández

    2012-11-01

    Full Text Available Certain aspects of the reproductive dynamics of Argentine red shrimp Pleoticus muelleri (Bate, 1888, distributed between 42°-47°S and 62°W, were investigated. Data and samples were collected during 36 INIDEP research cruises and 87 commercial fishing fleet trips between 1994-2010. Mature and inseminated females size structure as well as the frequency distribution of macroscopic maturity stages of adult females were analyzed on space-time bases. The seasonal development of ovarian maturity stages microscopically determinated was also assessed. Statistical treatment of data included multivariate scaling and cluster analysis. The reproductive activity of the shrimps showed latitudinal differences concerning its onset and duration that could be associated with the variability of environmental conditions. We discuss a shoreward movement of spawning females related to the presence of coastal hydrographic processes that would ensure retention and food for survival of early life stages.Se estudian ciertos aspectos de la dinámica reproductiva del langostino Pleoticus muelleri (Bate, 1988 en el área comprendida entre 42°-47°S y 62°W. Los datos y las muestras analizadas provienen de 36 campanas de investigación del INIDEP y de 87 viajes de la flota comercial langostinera realizados entre 1994 y 2010. Se analiza la estructura de tallas de las hembras maduras e impregnadas, al igual que la distribución de frecuencias de los distintos estadios de madurez sexual de las hembras adultas diferenciados macros-cópicamente, desde un enfoque espacio-temporal. La evolución estacional de los estadios de desarrollo ovárico determinados histológicamente también fue contemplada. El tratamiento estadístico de los datos comprendió un escalamiento multivariado y un análisis de agrupamiento jerárquico. La actividad reproductiva del langostino presenta diferenciaciones latitudinales con respecto a su inicio y duración que podría relacionarse con la variabilidad de las condiciones ambientales. Se discute la relación entre el movimiento hacia la costa de las hembras impregnadas y la presencia de procesos hidrográficos costeros que asegurarían la retención y disponibilidad de alimento para la supervivencia de las primeras etapas de vida.

  17. Ostrea puelchana (D'Orbigny 1842: a new host of Tumidotheres maculatus (Say, 1818 in northern Patagonia, Argentina Ostrea puelchana D’Orbigny 1842 nuevo hospedador de Tumidotheres maculatus (Say, 1818 en el norte de Patagonia, Argentina

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    María del Socorro Doldan

    2012-03-01

    Full Text Available Tumidotheres maculatus has been reported as a commensal of Mytilus platensis and Atrina seminuda and suggested as a parasite of Aequipecten tehuelchus in San Matías Gulf (SMG. The native flat oyster, Ostrea puelchana, has been studied in SMG for decades, and no crab-oyster association has been reported. In autumn-spring 2009 and 2010, oysters were collected from four banks in SMG, and the occurrence of T. maculatus inside the pallial cavity of O. puelchana was recorded. The prevalence varied between sites, with 0-12.5% at El Sótano, 0-16.7% at Caleta de los Loros, and no crabs found in the samples from Las Grutas and Puerto Lobos. Infected oysters hosted a single crab. Oysters were infested by either one male (47.7% or one female (15.1%. A positive but low correlation was found for male crab size and oyster size. The presence of these crabs inside the oysters could be due to the overlap of the distribution areas of O. puelchana and other bivalve hosts. Our findings may also be a consequence of local fishing. Commercial extraction of traditional hosts may have caused crabs to look for new hosts.En el Golfo San Matías (GSM, Tumidotheres maculatus ha sido registrado como comensal de Mytilus platensis y Atrina seminuda, y se lo ha indicado como parásito de Aequipecten tehuelchus. La ostra plana nativa Ostrea puelchana ha sido objeto de estudio por décadas en el GSM y no existen precedentes sobre una asociación entre las ostras y el cangrejo pinotérido. Durante otoño-primavera de 2009 y de 2010 se recolectaron ostras de cuatro bancos del GSM, registrándose la ocurrencia de T. maculatus en la cavidad paleal de O. puelchana. La prevalencia varió entre los sitios: 0-12,5% en El Sótano, 0-16,7% en Caleta de los Loros; no se encontraron cangrejos en los muestreos en Las Grutas y en Puerto Lobos. Se encontró un único cangrejo por hospedador; las ostras estuvieron infestadas por cangrejos macho (47,7%, o hembras (15,1%. Se encontró una correlación positiva pero baja entre la talla de los cangrejos macho y la talla de las ostras. La presencia del cangrejo en esta ostra podría ser causada por el solapamiento de áreas de distribución de O. puelchana con otros bivalvos hospedadores. Por otra parte, podría representar una consecuencia de la pesca en el área. Debido a la extracción comercial, los crustáceos habrían comenzado a buscar nuevos hospedadores.

  18. Phyto climatic characterization and cartography of sub antarctic native forests in Isla Grande de Tierra del Fuego (Patagonia, Argentina); Caracterizacion y cartografia fitoclimaticas del bosque nativo subantartico en la Isla Grande de Tierra del Fuego (Patagonia, Argentina)

    Energy Technology Data Exchange (ETDEWEB)

    Allue, C.; Arranz, J. A.; Bava, J. O.; Beneitez, J. M.; Collado, L.; Garcia-Lopez, J. M.

    2010-07-01

    Isla Grande de Tierra del Fuego is especially peculiar in phytoclimatic terms, situated as it is at an extreme southerly latitude, surrounded by large water masses and close to the great mass of Antarctic ice. Its main peculiarities in this sense are the coolness of its summers and a very narrow temperature range. As a result, the woodland landscapes in the parts with forest cover are dominated by microphyllous broadleaf physiognomies, both evergreen and deciduous, of the Nothofagus genus. This paper reports a more in-depth investigation of the hitherto little-known phytoclimatic conditions in that territory which included calibration and validation of a model of phytoclimatic suitability that addresses the principal plant physiognomic units and phytoclimatic mapping. It discusses the causes behind the presence of broadleaf formations in thermal conditions which in the northern hemisphere would allow only coniferous formations or no tree formations at all, and also the edaphic peculiarities that may explain the presence of a evergreen species like Nothofagus betuloides in subantarctic mixed forests. (Author) 111 refs.

  19. La fertilidad química del suelo y el «mal del ciprés» en Patagonia, Argentina Soil chemical fertility and austrocedrus chilensis disease in Patagonia, Argentina

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    Daniela Morales

    2011-12-01

    Full Text Available Los bosques de Austrocedrus chilensis sufren un proceso de mortalidad conocido como «mal del ciprés», cuya causa es aún discutida. Estudios previos sugieren la presencia de Phytophthora austrocedrae como agente causal de la mortalidad; sin embargo, el origen de la enfermedad continúa en estudio, dado que existen áreas afectadas no vinculadas con Phytophthora. El suelo, principalmente a través de sus características físicas y morfológicas, fue evidenciado como un factor asociado con la aparición y desarrollo de la enfermedad. En este trabajo, se evaluó la fertilidad química del suelo en relación al «mal del ciprés». Se seleccionaron cuatro sectores ubicados en el Valle «16 de Octubre» de la provincia del Chubut correspondientes a bosques puros y densos de A. chilensis. En cada sector se instalaron parcelas en áreas del bosque con síntomas severos de la enfermedad y en áreas sin síntomas. A su vez se incorporaron al estudio ocho parcelas control, ubicadas en bosques completamente sanos. Se tomaron muestras del horizonte A y se caracterizaron las propiedades químicas del suelo. No se encontraron deficiencias nutricionales y se observó un buen estado nutricional en todos los suelos analizados, aún en los bosques afectados, reflejándose en valores adecuados de materia orgánica, nitrógeno, bases y capacidad de intercambio catiónico. Se manifestaron diferencias entre los suelos bajo bosque afectado y suelos bajo bosques control en los contenidos de suma de bases, saturación de bases, calcio, pH NaF y fósforo. Estas diferencias podrían estar asociadas tanto a las condiciones de drenaje como a la presencia de Phytophthora.Austrocedrus chilensis forests suffer a widespread mortality locally known as «mal del ciprés» (cypress disease whose cause remains controversial. Previous studies suggested Phytophthora austrocedrae as the biotic cause; however, the origin of the mortality is still being studied since there are affected areas not connected with Phytophthora. The soil was proved to be an important factor affecting the disease. The purpose of this article was to study soil chemical properties related to A. chilensis disease. Four sampling sites with A. chilensis dense forests developed on different types of soils were selected in the 16 de Octubre Valley (Chubut province, Argentine. In each of them, pairs of plots that differed in disease symptoms were established. Each pair included a plot with an advanced degree of disease (diseased plot and another that did not exhibit symptoms (asymptomatic plot. Eight plots were included in the control forests, where the disease was totally absent. In each plot, a soil sample from the A horizon was collected for chemical analyses. This study showed high soil chemical fertility in all the forest soils, with high contents of organic matter, nitrogen, exchangeable cations and high cation exchange capacity. Differences between diseased forests and control forests were found for the following properties: sum of bases, base saturation, calcium, pH NaF and phosphorus. These differences could be associated with the drainage conditions and may also be associated to the presence of Phytophthora.

  20. Last millenium environmental changes in Lake Bertrand sediments, Chilean Patagonia

    Science.gov (United States)

    Sacré, V.; Fagel, N.; Schmidt, S.; Alvarez, D.; Araneda, A.; Urrutia, R.

    2012-04-01

    Our study focuses on a multiproxy analysis of sedimentary records from Lago Bertrand (area 50 km2; 227 masl; 46°55'S 72°50'W). Three cores were retrieved during fieldtrips in 2009 and 2011 with an Uwitec gravity corer. One core was collected in the main lake (LBt09, 102 cm) and two others in a lateral extension (LBb11-A, 162 cm and LBb11-B, 156 cm). Data 210Pb and 137Cs give average sedimentation rates of 2 mm/yr for the upper core section from the main lake, allowing a decennial resolution. Our aim is to document the climatic variability during the last millennium in Northern Patagonia and its impact on the environment. Lago Bertrand is separated from a pro-glacial lake (Lago Plomo) by a morainic barrier. The sediments of this lake are mainly composed of clayed silts and very few sandy silts. In the cores from the Eastern branch of Lago Bertrand, X-ray radiographies and magnetic susceptibility profiles evidence well-defined pluri-millimetric laminations with organic-rich layers, especially in the central core section. In the main lake, X-ray radiographies show diffuse pluri-millimetric laminations while magnetic susceptibility profiles do not confirm it. The sediments of the main lake appear more homogeneous with less organic-rich layers. They are characterized by low C/N ratio (10), supporting an important aquatic productivity; high inorganic content (90-95% of the bulk sediment); two peaks in the biological silica profile; and abundant diatoms (50-100 µm). According to the age model, the changes in aquatic productivity occurred between 1700 and 1850 AD. The cores from the Eastern branch of Lago Bertrand are under investigation to confirm the extension of the sedimentological changes observed in the main lake. The main sedimentological change observed in Lago Bertrand occurs during an interval equivalent to a part of the Little Ice Age. A similar biogenic silica-rich layer was also recorded in another relatively distant lake (Lago Thompson at 45°30'S, 72°47

  1. Plantas medicinales, comestibles y aromáticas en cercos vivos de una ciudad patagónica de Argentina: características y potencialidades de un recurso poco explorado

    OpenAIRE

    Molares, Soledad; Rovere, Adriana

    2016-01-01

    Los cercos vivos urbanos tienen un rol significativo por ser reservorios de biodiversidad y por las funciones socioeconómicas que pueden sustentar. En Bariloche (Río Negro, Patagonia Argentina) se estudiaron 300 cercos familiares, la riqueza de especies leñosas componentes, sus usos medicinales y comestibles, presencia de aromaticidad, como así también su disponibilidad en comercios locales. Los cercos se componen de 86 especies, entre estas las más frecuentes son las exóticas: Cytisus scopar...

  2. El acceso abierto en Argentina

    OpenAIRE

    De-Volder, Carolina

    2012-01-01

    The main objectives of this paper are: 1) Establish the concept of open access to scientific production, the means to achieve its objectives and benefits, 2) present some background research on the subject in Argentina, 3) List some initiatives and policies being undertaken in the country, 4) describe the production of Argentina in the E-LIS repository theme.

  3. Ash storms: impacts of wind-remobilised volcanic ash on rural communities and agriculture following the 1991 Hudson eruption, southern Patagonia, Chile

    Science.gov (United States)

    Wilson, T. M.; Cole, J. W.; Stewart, C.; Cronin, S. J.; Johnston, D. M.

    2011-04-01

    Tephra fall from the August 1991 eruption of Volcán Hudson affected some 100,000 km2 of Patagonia and was almost immediately reworked by strong winds, creating billowing clouds of remobilised ash, or `ash storms'. The immediate impacts on agriculture and rural communities were severe, but were then greatly exacerbated by continuing ash storms. This paper describes the findings of a 3-week study tour of the diverse environments of southern Patagonia affected by ash storms, with an emphasis on determining the impacts of repeated ash storms on agriculture and local practices that were developed in an attempt to mitigate these impacts. Ash storms produce similar effects to initial tephra eruptions, prolonged for considerable periods. These have included the burial of farmland under dune deposits, abrasion of vegetation and contamination of feed supplies with fine ash. These impacts can then cause problems for grazing animals such as starvation, severe tooth abrasion, gastrointestinal problems, corneal abrasion and blindness, and exhaustion if sheep fleeces become laden with ash. In addition, ash storms have led to exacerbated soil erosion, human health impacts, increased cleanup requirements, sedimentation in irrigation canals, and disruption of aviation and land transport. Ash deposits were naturally stabilised most rapidly in areas with high rainfall (>1,500 mm/year) through compaction and enhanced vegetation growth. Stabilisation was slowest in windy, semi-arid regions. Destruction of vegetation and suppression of regrowth by heavy tephra fall (>100 mm) hindered the stabilisation of deposits for years, and reduced the surface friction which increased wind erosivity. Stabilisation of tephra deposits was improved by intensive tillage, use of windbreaks and where there was dense and taller vegetative cover. Long-term drought and the impracticality of mixing ash deposits with soil by tillage on large farms was a barrier to stabilising deposits and, in turn

  4. [Estacionalidad de parásitos intestinales en suelos periurbanos de la ciudad de Neuquén, Patagonia, Argentina].

    Science.gov (United States)

    Pierangeli, Nora Beatriz; Giayetto, Alejandro Lorenzo; Manacorda, Ana Maria; Barbieri, Liliana Marta; Soriano, Silvia Viviana; Veronesi, Alicia; Pezzani, Betina Cecilia; Minvielle, Marta Cecilia; Basualdo, Juan Angel

    2003-03-01

    To determine the presence of eggs, larva, cysts and oocysts of intestinal parasites in the soil of a suburb of Neuquén city during 1 year in order to evaluate their seasonal fluctuations in relation to climatic data and soil characteristics in the studied area. A total of 107 soil samples were processed for parasite isolation by sedimentation and flotation methods during the four seasons of the year. Meteorological data were registered and physical, chemical and structural characteristics of the soil were analysed. About 28.9% of the soil samples were positive for at least one parasite form. Six protozoa species (cysts of Entamoeba sp., Enteromonas sp., Endolimax sp., Giardia sp., Iodamoeba sp. and coccidia oocysts) were recovered, but neither larvae nor eggs of human or animal helminths parasites were detected. The percentage of contaminated soil samples and the diversity of species showed a marked decrease in the warm and dry months of the summer. The soil was sandy, without vegetable cover, well drained, and with scarce organic matter content. The frequencies of parasite recovery and the number of species show seasonal fluctuations related to the rainfall. The importance of soil as a risk factor for the transmission of intestinal parasites in the studied area is conditioned by its structural characteristics, which prevent retaining the humidity, and by climatic variables. The interrelation of both factors determines unfavourable conditions that could explain the low level of contamination observed in soil as well as the absence of eggs and helminth larvae.

  5. Primera cita de la especie Goniozus legneri (Hymenoptera: Bethylidae en el Alto Valle de Río Negro, Patagonia Argentina

    Directory of Open Access Journals (Sweden)

    Silvina GARRIDO

    2005-01-01

    Full Text Available Se reporta por primera vez para la zona del Alto Valle de Río Negro, a Goniozus legneri Gordh, parasitando naturalmente larvas de Cydia pomonella (L, "carpocapsa", en montes comerciales de manzanos y nogales. Se comentan brevemente su hallazgo, características morfológicas, distribución, biología e influencia en las poblaciones de "carpocapsa".

  6. Primera cita de la especie Goniozus legneri (Hymenoptera: Bethylidae) en el Alto Valle de Río Negro, Patagonia Argentina

    OpenAIRE

    Silvina GARRIDO; Liliana CICHÓN; Darío FERNÁNDEZ; Celso AZEVEDO

    2005-01-01

    Se reporta por primera vez para la zona del Alto Valle de Río Negro, a Goniozus legneri Gordh, parasitando naturalmente larvas de Cydia pomonella (L), "carpocapsa", en montes comerciales de manzanos y nogales. Se comentan brevemente su hallazgo, características morfológicas, distribución, biología e influencia en las poblaciones de "carpocapsa".

  7. Inventario preliminar y nuevos registros de Psychodidae no Phlebotominae (Diptera, Nematocera para Argentina, con especial referencia a la Patagonia

    Directory of Open Access Journals (Sweden)

    Guillermo H. OMAD

    2012-01-01

    y Nemoneura dealbata Tonnoir. Los sitios de muestreo para este trabajo se realizaron en diferentes zonas de las provincias de Chubut (Parque Nacional Los Alerces, Río Negro y Neuquén (Parque Nacional Nahuel Huapi, Buenos Aires y Misiones.

  8. Maritrema huillini (Digenea: Microphallidae) en mustélidos (Carnivora: Mustelidae) de ambientes de agua dulce de la Patagonia (Argentina)

    OpenAIRE

    Flores, Verónica Roxana; Brugni, N.

    2016-01-01

    El conocimiento sobre los parásitos metazoos de mustélidos sudamericanos está centrado principalmente en las especies de los géneros Lontra y Galictis, con registros de digeneos, nematodes y acantocéfalos. Se examinaron 7 especimenes de mustélidos: 2 Galictis cuja (hurón menor), 1 Lyncodon patagonicus (huroncito) y 4 Neovison vison (visón americano) colectados en el Parque Nacional Nahuel Huapi (PNNH). Todos los especimenes de N. vison analizados, presentaron infestaciones con digeneos perten...

  9. Asociaciones de quistes de dinoflagelados de agua salobre a dulce de la formacion la colonia (Paleoceno?), Noreste de Patagonia, Argentina

    NARCIS (Netherlands)

    Guler, M. Verónica; Borel, C. Marcela; Brinkhuis, Henk; Navarro, Edgardo; Astini, Ricardo

    A palynological analysis of the section of La Colonia Formation exposed at Estancia San Miguel yielded conspicuous assemblages of organic-walled dinoflagellate cysts (dinocysts) and green algae. The monotypic palaeoperidinioid dinocyst assemblage of ?Ginginodinium sp. in the basal beds of this

  10. Sistemas Conversores Fluido - Dinámicos de energía renovable para la Patagonia Argentina

    Directory of Open Access Journals (Sweden)

    Mauro Ezequiel Vitorino

    2016-08-01

    En esencia, este proyecto permite tener un conocimiento teórico acerca de los sistemas conversores hidrocinéticos y las necesidades prácticas para llevar a cabo un prototipo de dimensiones acotadas en un lugar determinado como podría ser Puerto san Julián.

  11. Etapas de crecimiento urbano de El Calafate, provincia de Santa Cruz, Patagonia Austral Andina Argentina : (1927-2010)

    OpenAIRE

    Ampuero, Cristian; Norambuena, Mónica; Cáceres, Alicia P.

    2016-01-01

    El Calafate localizada al Sudoeste de la Provincia de Santa Cruz, desde su fundación, 1927, hasta 1980 la actividad económica predominante fue la de servicios de la explotación ganadera. Desde 1980, es reemplazada por la turística, actividad que atrajo y atrae desplazamientos migratorios con distintos ritmos, que han incidido en el crecimiento demográfico y urbano. De este modo, el objetivo del trabajo es estudiar el crecimiento urbano de El Calafate desde 1927 hasta 2010...

  12. Bajo presión: primera relación sexual de adolescentes de Trelew (Argentina Under pressure: first sexual relation of teenagers from Trelew (Argentina

    Directory of Open Access Journals (Sweden)

    Daniel Eduardo Jones

    2010-08-01

    Full Text Available El artículo analiza las expectativas y experiencias relativas a la primera relación sexual de adolescentes, a partir de entrevistas semiestructuradas individuales a 22 varones y 22 mujeres, de entre 15 y 19 años de edad, pertenecientes a estratos socioeconómicos medios y residentes en Trelew, una ciudad de 100 mil habitantes en la Patagonia argentina. Se centra en los papeles esperados y las vivencias de presiones para la iniciación sexual. Los papeles esperados para varones y mujeres reflejan expectativas de género asimétricas y pueden favorecer acciones coercitivas por parte de parejas y amistades. Estas coerciones pueden ser interpretadas a partir del tipo de vínculo con la persona con que debutan sexualmente y la influencia de las redes de pares en tanto público interesado en dicho evento. El análisis de los testimonios tiene a la teoría de los guiones sexuales como marco de referencia, y considera las dimensiones de género y edad de las y los entrevistados.The article analyses the expectations and experiences related to the first sexual relation of teenagers. The research is based on individual semi-structured interviews with 22 men and 22 women aged from 15 to 19 , belonging to the middle class layer from Trelew, a city of 100,000 inhabitants in the Argentinean Patagonia. The article focuses on the expected roles and experiences of pressure for sexual initiation. Desired roles for girls and boys regarding their first sexual relation reflect asymmetric gender expectations and can lead to coercive actions of partners and friends. These coercions can be interpreted considering the relations with the sexual partner and the influence of teenagers' networks as a public interested in the first sexual relation. The testimonies are analyzed within a sexual scripting theory, and considering gender and age of the interviewed actors.

  13. LAS ESPECIES DE AZORELLA (AZORELLOIDEAE, APIACEAE CON DISTRIBUCIÓN EXTRA-ARGENTINA

    Directory of Open Access Journals (Sweden)

    Carolina I. Calviño

    2016-01-01

    Full Text Available Azorella es un género con 26 especies de Azorelloideae (Apiaceae que crecen desde Costa Rica hasta las islas subantárticas, siendo característico y dominante en distintos ambientes de las cordilleras andinas desde Venezuela hasta la Patagonia. Las especies de Azorella que crecen en Argentina fueron revisadas taxonómicamente en un estudio previo. Sin embargo, el conocimiento de las restantes especies es fragmentario y dispar. El objetivo de este trabajo es actualizar la información de las 11 especies de Azorella ausentes en Argentina y que crecen en Bolivia, Chile, Colombia, Ecuador, Perú y/o Venezuela. Se proporcionan las descripciones y mapas actualizados de la distribución de las especies, y se resuelven problemas nomenclaturales y de tipificación de 41 nombres, 2 especies tipo, 16 lectotipificaciones y 1 neotipificación. También se proveen 10 nuevas ilustraciones y una clave para identificar todas las especies del género.

  14. First description of the soft part anatomy of Ilyocypris ramirezi Cusminsky & Whatley (Crustacea, Ostracoda) from Argentina, South America.

    Science.gov (United States)

    D'Ambrosio, D Sabina; Díaz, Analía R; García, Adriana; Claps, María Cristina

    2015-05-13

    The anatomy of the soft parts of Ilyocypris ramirezi Cusminsky & Whatley, 1996 is described and illustrated for the first time, based on findings of this species from water bodies in the shallow areas of the Llancanelo basin, south-west of Mendoza Province, Argentina. This species is common in Quaternary and extant environments of the Pampa and Patagonian regions. Its distribution is now extending in Argentina to the Central-West area, locally named "Cuyo region". Ilyocypris ramirezi is a good environmental indicator and constitutes a useful tool in paleolimnological studies.

  15. Current status and perspectives of the development of dental research in biological anthropology of Argentina: introduction and conclusions of the symposium.

    Science.gov (United States)

    Luna, Leandro H; Bernal, Valeria

    2011-10-01

    This paper describes and discusses the research in the field of dental anthropology in Argentina. It has been presented at the symposium entitled "The development of dental research in Argentine Biological Anthropology: current status and perspectives", coordinated by the authors at the IX National Meeting of Biological Anthropology of Argentina, Puerto Madryn, 20th-23rd October 2009. The aim of the symposium was to present new results and future prospects of this discipline in the country and to create a forum for discussion of current research within this field. Six contributions that focused on the study of teeth from different perspectives and analysed bioarchaeological samples from different areas of Argentina (Central Highlands, Pampa and Patagonia) were presented. After the presentations, a discussion about the state of the art of dental research in the country was generated, in which the need for the generation of methodological consensus on the criteria for the evaluation of the variables considered was stated, so that research conducted in different areas can be compared. In short, the contributions of this symposium provide insights into the diversity of dental anthropology in contemporary Argentina and the potential of these types of studies to gain important information about biological and cultural aspects of the native populations in the country. Copyright © 2011 Elsevier GmbH. All rights reserved.

  16. Recent drainage events of glacial Lake Cachet 2, Patagonia

    Science.gov (United States)

    Casassa, G.; Wendt, J.; Wendt, A.; Escobar, F.; Lopez, P.; Carrasco, J.; Rivera, A.; Leidich, J.

    2009-04-01

    Lake Cachet 2 (47°12' S, 73°15' W, 422 m a.s.l.) is a proglacial lake of 4 km2 located on the eastern margin of the Northern Patagonia Icefield (3,953 km2, Rivera et al., 2007), which is dammed on its southern margin by Colonia Glacier. Until April 2008 there was no historical evidence of catastrophic flooding of this lake. In 2008 three sudden drainage events occurred at Lake Cachet 2 (April 6-7; October 7-8 and 21-22 December). During each event the flood wave traveled down Colonia River to the confluence with Baker River, then affected Baker River to a distance of up to 25 km upstream from the confluence and downstream all the way to its mouth on the Pacific Ocean fjords at Caleta Tortel (100 km to the southwest), transporting abundant sediments. In April the runoff of Baker River close to the confluence with Colonia River increased from a base level of 1,200 m3/s on April 7 to a peak runoff of 3,570 m3/s within a period of less than 48 hours, resulting in a river level increase of 4.5 m and an associated water temperature drop from 8°C to 4°C. In October the base level was 573 m3/s, with a peak runoff of 3,007 m3/s, a river level increase of 4.7 m and a water temperature drop from 7.3°C to 4.8°C, while in December the corresponding values were 1,145 m3/s, 3,052 m3/s, 11°C and 8°C. The flood affected roads, bridges, farms and cattle, fortunately not resulting in any human damage. Similar floods had been reported on Colonia River several decades ago, the last having occurred in the 1970s, all of which originated at that time at glacial Lake Arco, located south of Colonia Glacier. Airborne and ground explorations carried out after each event in 2008 confirmed that the floods originated at Lake Cachet 2, draining under Colonia Glacier for a distance of 8 km and emerging at the front of the glacier. As a result parts of the glacier front collapsed after each event, where large ice fractures could be observed. During the October event a complete drainage of

  17. Pobreza y migraciones en una ciudad intermedia argentina. Una mirada desde la historia (Neuquén, 1980

    Directory of Open Access Journals (Sweden)

    Joaquín Perren

    2015-01-01

    Full Text Available El presente artículo tiene como objetivo estudiar los vínculos entre la pobreza y las migra - ciones en Neuquén (Patagonia, Argentina a principios de la década de 1980. En tér - minos metodológicos, este estudio emplea la información que brinda el Censo Nacional de Población y Vivienda de 1980 por radio censal. Al mismo tiempo, y con el propósito de detallar muchos de los fenómenos que se analizan, se presentan cartografías temáticas que fueron elaboradas utilizando sistemas de información geográfica, y en particular el programa ArcView GIS 3.3.

  18. La proyección colonial de Chile a la Patagonia Insular en el siglo XVIII

    Directory of Open Access Journals (Sweden)

    Urbina Carrasco, María Ximena

    2011-12-01

    Full Text Available In this article, the geopolitical consequences of the shipwreck of the English frigate Wager and the landfall of the ship Anna into the coasts of the Western Insular Patagonia in 1741 are presented, which were part of the fleet of George Anson. The news reporting the English presence in the deserted and unknown insular and coastal territory southernmost Chiloé, and which had disseminated towards the end of the continent, promoted the deployment of different actions tending to make presence noted, such as military and missionary expeditions, fort establishment and area patrols. None of the latter implied a permanent settlement or effective incorporation of such border, although they indeed involved the creation of a «mobile frontier» for Chiloé and the development of a Western Patagonia image.

    Este artículo presenta las consecuencias geopolíticas del naufragio de la fragata inglesa Wager y la recalada de otro barco, el Anna, que formaban parte de la flota de George Anson, en las costas de la Patagonia Occidental Insular en 1741. La noticia de la presencia inglesa en el despoblado y desconocido territorio insular y bordemarino al sur de Chiloé, y que se proyectaba al fin del continente, generó el despliegue de acciones tendentes a marcar presencia, como expediciones militares y misionales, la fundación de un fuerte y el patrullaje por la zona. Nada de esto se tradujo en un asentamiento permanente o incorporación efectiva de dicha frontera, pero si en la conformación de una «frontera móvil» de Chiloé, y la construcción de una imagen de la Patagonia Occidental.

  19. Spatial dynamics of Fabiana imbricata shrublands in northwestern Patagonia in relation to natural fires

    OpenAIRE

    F. J. Oddi; Dudinszky, N.; L. Ghermandi

    2010-01-01

    Fire is a critical disturbance in the structuring and functioning of most Mediterranean ecosystems. In northwestern Patagonia, vegetation patterns are strongly influenced by fire and environmental heterogeneity. Dendroecology, together with satellite imagery and GIS, have been demonstrated to be useful tools in studies that relate to fire effects with patches, patterns and species dynamics at landscape scale. Such studies can be approached from landscape ecology, which has evolved in the last...

  20. El conocimiento geográfico de la Patagonia interior y la construcción de la imagen de Torres del Paine como patrimonio natural a conservar

    Directory of Open Access Journals (Sweden)

    Ferrer Jiménez, Daniel

    2009-06-01

    primeras propuestas de turismo de naturaleza asociado a la idea de la conservación y un reto de primer orden para las expediciones alpinas.

    Esas circunstancias explican que en la tesis doctoral del autor del presente artículo se dedicase un capítulo completo a analizar las principales aportaciones en el proceso de conocimiento geográfico de la Patagonia interior y construcción de la imagen de Torres del Paine como patrimonio natural a conservar. Sobre este tema versa precisamente este texto, en el que se aporta una información original sobre las exploraciones de reconocimiento geográfico que tuvieron lugar entre 1877 y 1896 en la Patagonia interior, por iniciativa de los gobiernos de Chile y Argentina; el primer viaje turístico conocido a la región chilena de Magallanes; el papel de los primeros “visionarios” del turismo andino-patagónico chileno, agrupados en torno a la figura de Werner Gromsh y el Touring Club; o la labor geográfica, científica y divulgativa desempeñada por el salesiano italiano Alberto Maria De Agostini. El artículo concluye con algunas consideraciones relativas a las primeras expediciones alpinísticas que tuvieron como objetivo las cumbres del Macizo del Paine.

  1. Cretaceous/Paleogene floral turnover in Patagonia: drop in diversity, low extinction, and a Classopollis spike.

    Directory of Open Access Journals (Sweden)

    Viviana D Barreda

    Full Text Available Nearly all data regarding land-plant turnover across the Cretaceous/Paleogene boundary come from western North America, relatively close to the Chicxulub, Mexico impact site. Here, we present a palynological analysis of a section in Patagonia that shows a marked fall in diversity and abundance of nearly all plant groups across the K/Pg interval. Minimum diversity occurs during the earliest Danian, but only a few palynomorphs show true extinctions. The low extinction rate is similar to previous observations from New Zealand. The differing responses between the Southern and Northern hemispheres could be related to the attenuation of damage with increased distance from the impact site, to hemispheric differences in extinction severity, or to both effects. Legacy effects of the terminal Cretaceous event also provide a plausible, partial explanation for the fact that Paleocene and Eocene macrofloras from Patagonia are among the most diverse known globally. Also of great interest, earliest Danian assemblages are dominated by the gymnosperm palynomorphs Classopollis of the extinct Mesozoic conifer family Cheirolepidiaceae. The expansion of Classopollis after the boundary in Patagonia is another example of typically Mesozoic plant lineages surviving into the Cenozoic in southern Gondwanan areas, and this greatly supports previous hypotheses of high latitude southern regions as biodiversity refugia during the end-Cretaceous global crisis.

  2. QUBIC in Argentina

    Science.gov (United States)

    García, B.; Harari, D.; Etchegoyen, A.; Medina, M. C.; Romero, G. E.; Qubic Collaboration

    2017-10-01

    QUBIC (QU Bolometric Interferometer for Cosmology) is an experimental cosmology project to measure the modes in the polarization of the cosmic background radiation (CBR), the fossil relic that reveals the properties at the Universe 380,000 years after the Planck Era. Discovery of the CBR in 1964 and measurement of tiny temperature anisotropies in 1992 were major breakthroughs in our understanding of the Universe. The next challenge is to measure the polarization of the CBR accurately enough to detect modes that would reveal the existence of primordial gravitational waves produced in the first stages of the Planck Era and probe inflation theory, that assumes an accelerated expansion during the first seconds. The mode signal is however extremely weak and its measurement requires complex instruments. The QUBIC collaboration has developed the concept of interferometric bolometry, that brings together the sensitivity of bolometric detectors with the control of systematic effects provided by interferometry. QUBIC is an international collaboration involving several universities and laboratories in France, Italy, United Kingdom and USA. Recently, Argentina has suggested Alto Chorrillo (Salta), as candidate site for the installation of the experiment, next to the LLAMA site. Here we describe the scientific objectives and the main features of the experiment and we detail the process through which the international collaboration decided to install in Argentina its first module as well as the challenges for our country in this project.

  3. [Anuran fauna from Salta city, Argentina].

    Science.gov (United States)

    Acosta, Rebeca; Mesones, Rosa Vera; Núñez, Alejandro

    2005-01-01

    The loss and transformation of habitat by anthropogenic activities is one of the main causes of biodiversity decrease. Amphibians are declining all over the world and one of the causes of this decline is thought to be habitat reduction. However, there are anuran populations in highly disturbed habitats, like cities. This study presents the ecological baseline needed to understand anuran communities in urban environments, for Salta City. Argentina (ca. 502,000 inhabitants). The sample was stratified by environments defined by infrastructure and geographic location. The species were identified by visual encounter techniques and by auditory transect during the 2002-2003 reproductive period. Three families, seven genera and twelve species were recorded and the species richness decreased from city border to center. Similarity index values among geographic areas was higher East-West (94.7) than South-West (33.3). Bufo arenarum was the only species recorded in all environments. Hyla andina and Odontophrynus americanus had a restricted distribution and are here considered vulnerable. The border effect can explain some distribution pattern in these populations. A map of the potential distribution of recorded species for Salta is provided.

  4. Oakland, West

    OpenAIRE

    Kwamille, Tasion Shawniece

    2013-01-01

    “Oakland, West” Produced by: Tasion Kwamilele          After World War II, many blacks from the south migrated to Oakland to work in the shipyards; housing discrimination forced blacks to move to West Oakland. But when those jobs died out many Blacks moved from West Oakland and the area became deserted and filled with crime, drugs, violence, and poverty.         The 7.0 Loma Prueta Earthquake, also known as the World Series Quake of 1989, shook the Bay Are...

  5. [Serological evidence of St. Louis encephalitis virus circulation in birds from Buenos Aires City, Argentina].

    Science.gov (United States)

    Beltrán, Fernando J; Díaz, Luis A; Konigheim, Brenda; Molina, José; Beaudoin, Juan B; Contigiani, Marta; Spinsanti, Lorena I

    2015-01-01

    Our goal was to determine the presence of neutralizing antibodies against St. Louis encephalitis virus (SLEV) and West Nile virus (WNV) in sera of wild and domestic birds from Buenos Aires City, Argentina. From October 2012 to April 2013, 180 samples were collected and processed by the microneutralization technique. A 7.2% of the sampled birds were seropositive for SLEV, while no seropositive birds for WNV were detected. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  6. Demographics of the Disappearing Bottlenose Dolphin in Argentina: A Common Species on Its Way Out?

    Science.gov (United States)

    Vermeulen, Els; Bräger, Stefan

    2015-01-01

    Populations of the once common bottlenose dolphin (Tursiops truncatus) in Argentina have precipitously declined throughout the country in the past decades. Unfortunately, local declines of common species are easily overlooked when establishing priorities for conservation. In this study, demographics of what may well be the last remaining resident population in the country were assessed using mark—recapture analysis (Pollock’s Robust Design) of a photo-identification dataset collected during 2006–2011 in Bahía San Antonio (Patagonia, Argentina). Total abundance, corrected for unmarked individuals, ranged from 40 (95%CI: 16.1–98.8) to 83 (95%CI = 45.8–151.8) individuals and showed a decrease over the years. Adult survival rates varied between 0.97 (± 0.037 SE) and 0.99 (± 0.010 SE). Average calving interval equalled 3.5 ± 1.03 years, with 3.5 births/year in the entire population and a minimum annual birth rate of 4.2%. However, data suggest that calves may have been born and lost before being documented, underestimating birth rate, calf mortality, and possibly the number of reproductive females. Either way, the recruitment rate of calves appears to be insufficient to support the size of the population. This population is relatively small and declining. Considering the disappearance of populations north and south of the study area, an incessant decline will have severe consequences for the continuous existence of this species in Argentina, indicating an urgent need for serious conservation efforts. This study provides insight into how the failure to recognize local population declines can threaten the national (and eventually the international) status of a common species like the bottlenose dolphin. PMID:25786234

  7. Marcas urbanas y sentidos sociales en disputa. San Carlos de Bariloche, Argentina, 1966-1983

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    Paula Gabriela Núñez

    2013-07-01

    Full Text Available San Carlos de Bariloche es la principal localidad turística de la Patagonia argentina. Representa, por su dimensión, a la ciudad más poblada de la provincia de Río Negro y es la tercera en tamaño en la Patagonia. Su crecimiento demográfico ha estado nutrido por diferentes migraciones nacionales y extranjeras. De estas últimas las principales provienen de países latinoamericanos. El artículo apunta a indagar en  la desvalorización de su migración más importante, la chilena, durante la segunda mitad del siglo XX. Esta exclusión se fortaleció entre 1966 y 1983, por las iniciativas estatales que exacerbaron la xenofobia, las persecuciones políticas, la precarización de las condiciones laborales y los cambios en la organización espacial durante los gobiernos dictatoriales del período, esto es, los que se desarrollaron de 1966 a 1973 y de 1976 a 1983. El presente artículo analiza cómo algunos espacios de Bariloche se constituyeron en marcas urbanas que representaron intereses de los sectores más visibles en nombre de la “nación”, al tiempo que revisa dispositivos de resistencia de sectores excluidos de migrantes chilenos, que tuvieron, paralelamente, componentes de construcción espacial. Para este último punto se aborda la construcción de la Capilla Nuestra Señora del Carmen en 1966, construida en el área conocida como “barrio de los chilenos”, que se levantó como una marca alternativa, tanto material como simbólica, para disputar pertenencia, reconocimiento y visibilidad.

  8. Le site paléo-indien de Piedra Museo (Patagonie). Sa contribution au débat sur le premier peuplement du continent américainThe palaeo-indian site of Piedra Museo (Patagonia). Its contribution to the debate on the peopling of the Americas.

    Science.gov (United States)

    Ramirez Rozzi, Fernando V.; d'Errico, Francesco; Zarate, Marcelo

    2000-08-01

    The Piedra Museo site (Santa Cruz, Argentina), excavated over the past nine years has yielded a rich archaeological record, which contributes to the discussion on the first peopling of the Americas. We present here a new study of the site, based on an analysis of the stratigraphy, spatial distribution of archaeological remains, bone taphonomy, and discussion of new AMS- 14C dates. We conclude that remains of extinct species with cut-marks from the lower levels are contemporaneous of stone tools and cores from the same levels. This demonstrates that humans were present in the southern part of Patagonia around 10 300 and 11 100 years BP and suggests that hunting of large mammals was a part of their subsistence strategies.

  9. Los derechos en Argentina

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    David Landesman

    2015-01-01

    Full Text Available El discurso oficial argentino, en diferentes tipos de gobierno, ha acuñado una idea fuerza que se resume en: "Argentina es una nación de paz". Su historia violenta, plagada de terrorismo de Estado,y de facciones, las carencias económicas sociales y culturales desmiente esta aseveración. "Los argentinos somos derechos y humanos". Slogans,para encubrir la verdad que fue otra. Sino que lo digan los 30.000 desaparecidos. Periodistas muertos, desaparecidos o exiliados. Las publicaciones periódicas sometidas a control previo de sus contenidos. Sospechosos silencios de organizaciones de derechos humanos. Trata sobre las Madres de Mayo y sus tácticas y el aparente cambio de los medios luego del ascenso al poder del presidente electo Raúl Alfonsín y el juicio a los miembros de la Juntas militares .

  10. Metropolization in Argentina

    OpenAIRE

    Dagnino Pastore, José María; Canavese, Paula

    1996-01-01

    A partir de la regla de "orden-magnitud" el trabajo formula el concepto de "metropolización" (Smger) y explicita su relación con el índice de urbanización usual. Rastrea la evolución de la metropolización en Argentina a través de sus ocho censos, tanto para el conjunto de todos los centros urbanos como para tres subconjuntos: grandes, medianos y pequeños. El trabajo presenta después la idea de economías de "concentración geográfica" de las actividades (Lösch), explorando su relación -bajo sup...

  11. nueva realidad de Argentina

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    Roberto Miranda

    2011-01-01

    Full Text Available Una de las características de la política latinoamericana de los últimos tiempos ha sido la tensión entre integración y fragmentación. En este contexto hubo una reproducción de situaciones conocidas. Pero también se procesaron cambios importantes. Uno de éstos estuvo relacionado con la irrupción de los liderazgos regionales, de naturaleza y envergadura diversa. Encontramos una puja muy particular entre el liderazgo de Venezuela en un proyecto alternativo y la respuesta geopolítica de Estados Unidos a través de Colombia. La realidad de los liderazgos impactó notoriamente a Argentina. Fue evidente que a partir de la crisis de 2001 perdió capacidad de influencia en la región.

  12. Refertilization process in the Patagonian subcontinental lithospheric mantle of Estancia Sol de Mayo (Argentina)

    Science.gov (United States)

    Melchiorre, Massimiliano; Coltorti, Massimo; Gregoire, Michel; Benoit, Mathieu

    2015-05-01

    Anhydrous mantle xenoliths equilibrated at 1003-1040 °C from Estancia Sol de Mayo (ESM, Central Patagonia, Argentina) and entrained in post-plateau alkaline lavas belonging to Meseta Lago Buenos Aires have been investigated aiming at reconstructing the depletion and enrichment processes that affected this portion of the Patagonia lithospheric mantle. Xenoliths are characterized by a coarse-grained protogranular texture and are devoid of evident modal metasomatism. They show two texturally different clinopyroxenes: protogranular (cpx1) and texturally related to spinel (cpx2). Three different types of orthopyroxenes are also recognized: large protogranular crystals with exsolution lamellae (opx1); small clean and undeformed grains without exsolution lamellae (opx2) and small grains arranged in a vein (opx3). Major element composition of clinopyroxenes and orthopyroxenes highlights two different trends characterized by i) a high Al2O3 content at almost constant mg# and ii) a slight increase in Al2O3 content with decreasing mg#. Clinopyroxenes are enriched in LREE and are characterized by prominent to slightly negative Nb, Zr and Ti anomalies. No geochemical differences are observed between cpx1 and cpx2, while a discrimination can be observed between opx1 and opx2 (LREE-depleted; prominent to slightly negative Ti and Zr anomalies) and opx3 (prominent positive Zr anomaly). Partial melting modeling using both major and trace elements indicates a melting degree between ~ 5% and ~ 13% (up to ~ 23% according to major element modeling) for lherzolites and between ~ 20% and ~ 30% for harzburgites (down to ~ 5% according to trace element modeling). La/Yb and Al2O3, as well as Sr and Al2O3 negative correlations in clinopyroxenes point to a refertilization event affecting this lithospheric mantle. The agent was most probably a transitional alkaline/subalkaline melt, as indicated by the presence of orthopyroxene in the vein and the similar geochemical features of ESM

  13. A new sauropodomorph dinosaur from the Early Jurassic of Patagonia and the origin and evolution of the sauropod-type sacrum.

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    Diego Pol

    Full Text Available BACKGROUND: The origin of sauropod dinosaurs is one of the major landmarks of dinosaur evolution but is still poorly understood. This drastic transformation involved major skeletal modifications, including a shift from the small and gracile condition of primitive sauropodomorphs to the gigantic and quadrupedal condition of sauropods. Recent findings in the Late Triassic-Early Jurassic of Gondwana provide critical evidence to understand the origin and early evolution of sauropods. METHODOLOGY/PRINCIPAL FINDINGS: A new sauropodomorph dinosaur, Leonerasaurus taquetrensis gen. et sp. nov., is described from the Las Leoneras Formation of Central Patagonia (Argentina. The new taxon is diagnosed by the presence of anterior unserrated teeth with a low spoon-shaped crown, amphicoelous and acamerate vertebral centra, four sacral vertebrae, and humeral deltopectoral crest low and medially deflected along its distal half. The phylogenetic analysis depicts Leonerasaurus as one of the closest outgroups of Sauropoda, being the sister taxon of a clade of large bodied taxa composed of Melanorosaurus and Sauropoda. CONCLUSIONS/SIGNIFICANCE: The dental and postcranial anatomy of Leonerasaurus supports its close affinities with basal sauropods. Despite the small size and plesiomorphic skeletal anatomy of Leonerasaurus, the four vertebrae that compose its sacrum resemble that of the large-bodied primitive sauropods. This shows that the appearance of the sauropod-type of sacrum predated the marked increase in body size that characterizes the origins of sauropods, rejecting a causal explanation and evolutionary linkage between this sacral configuration and body size. Alternative phylogenetic placements of Leonerasaurus as a basal anchisaurian imply a convergent acquisition of the sauropod-type sacrum in the new small-bodied taxon, also rejecting an evolutionary dependence of sacral configuration and body size in sauropodomorphs. This and other recent discoveries are

  14. Primera ictiofauna marina del Cretácico Superior (Formación Jaguel, Maastrichtiano de la provincia de Río Negro, Argentina First marine ichthyofauna from the Upper Cretaceous (Jaguel Formation; Maastrichtian from Río Negro province, Argentina

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    Sergio Bogan

    2010-01-01

    Full Text Available Se describe un conjunto de dientes fósiles que proceden de sedimentos marinos de la Formación Jagüel (Maastrichtiano, de la localidad de Bajo Trapalcó, provincia de Río Negro, Patagonia, Argentina. La ictiofauna aquí descripta es la primera para la Formación y se compone de unos seis taxones diferentes de Chondrichthyes (Serratolamna serrata, Squalicorax pristodontus, Cretalamna appendiculata, Carcharias sp., Odontaspis sp. y cf. Pseudohypolophus mcnultyi y dos Teleostei del género Enchodus (aff. E. ferox y aff. E. gladiolus. Serratolamna serrata es el taxón mejor representado del conjunto, y constituye la cita más austral conocida en la distribución de esta especie y el primer registro fósil para Argentina. Los registros de Enchodus, Squalicorax pristodontus y cf. Pseudohypolophus mcnultyi, representan las primeras descripciones de estos taxones para Argentina. Todos los taxones descriptos constituyen un ensamblaje de especies que caracterizan las paleoictiofaunas de los mares del Cretácico Superior de distintas partes del globo, aportando novedosa información para la comprensión de las ictiofaunas Mesozoicas del cono sur sudamericano.This paper describes several fossil teeth coming from marine sediments from the Bajo Trapalcó locality, Río Negro province, Patagonia, Argentina. The ichthyofauna described here is composed by six different chondrichtyan taxa (Serratolamna serrata, Squalicorax pristodontus, Cretalamna appendiculata, Carcharias sp., Odontaspis sp. and cf. Pseudohypolophus mcnultyi and two Teleostei of the genus Enchodus (aff. E. ferox and aff. E. gladiolus. Serratolamna serrata is the most abundant species, and it represents the southernmost record for the species and the first record for Argentina. The records of Enchodus, Squalicorax pristodontus and cf. Pseudohypolophus mcnultyi, constitute the first mention for these taxa in Argentina. The taxa described here characterize the paleoichthyofaunas of the Upper

  15. Contrasting structural patterns of the mesozooplankton community result from the development of a frontal system in San José Gulf, Patagonia

    Science.gov (United States)

    Hernández-Moresino, Rodrigo D.; Di Mauro, Rosana; Crespi-Abril, Augusto C.; Villanueva-Gomila, Gabriela L.; Compaire, Jesus C.; Barón, Pedro J.

    2017-07-01

    The structural patterns of the mesozooplankton community of San José Gulf (SJG), a one of a kind semi-enclosed basin located in the northern margin of the Valdés Peninsula (Argentine Patagonia), were studied by means of semi-automatic image analysis. Samples were obtained bimonthly during the warm season (October 2012-April 2013) at stations distributed on a regular grid. Cluster analyses outlined two spatially consistent groups of stations showing similar patterns when based on physical (SST, Chl-a, and bottom depth) and community structure (abundance, biomass, and slope of the size spectra) descriptors, each broadly distributed on one of two previously described hydrographic domains formed by the interaction of tidal circulation, coastal morphology, bottom topography, and seasonal vertical stratification. Examination of the slope of the mesozooplankton size spectra revealed that the stratified waters of the East Domain sustain higher proportions of small organisms and higher biomass, suggesting potentially low trophic transfer efficiency compared to its vertically-mixed West counterpart. Three-clustering analyses resulted in still spatially consistent groups of stations when based on the community descriptors, revealing the existence of a transition zone, presumably resulting from intermediate hydrodynamic conditions. Principal component analysis revealed that biomass of cladocerans modulates the size spectra and is related with distances from sampling stations to SJG's mouth. Overall, a consistent spatial correlate was found between physical conditions of water masses and the structure of the mesozooplancton community contained within.

  16. 40Ar/ 39Ar dating of the Jurassic volcanic province of Patagonia: migrating magmatism related to Gondwana break-up and subduction

    Science.gov (United States)

    Féraud, G.; Alric, V.; Fornari, M.; Bertrand, H.; Haller, M.

    1999-10-01

    The Mesozoic large igneous province (LIP) of Patagonia (southern South America), which is one of the largest silicic provinces on Earth has been investigated by the 40Ar/ 39Ar method. Twenty-seven ages considered as valid, including twenty plateau ages, show that the volcanic activity, ranging from 187 to 144 Ma, occurred between and contemporaneously with the initial break-up of Gondwana (starting with the Karoo-Antarctic-Tasmanian (KAT) flood basalt province) in the east, and a subduction in the west. The data display a regular decreasing of ages from the ENE (187 Ma) to the WSW (144 Ma) along about 650 km, apparently related to the tectonic structure in half-grabens oriented NNW-SSE. The good fitting of this trend with the opening of the Rocas Verdes-Sarmiento marginal basin favors a space time evolution of this continental volcanism culminating towards the SSW in a continental disruption behind the magmatic arc. The observed age progression of volcanism may be the result of the variations of the physical characteristics of the subduction. The spreading and thermal effect of the KAT plume may have an additional effect and also could account for the unusually large volume of magma.

  17. First records of three species of Oxycraspedus Kuschel (Coleóptera: Belidae in Argentina and use of a predictive model to compare their potential distribution with the range of their host-plant, Araucaria araucana Primera cita de las tres especies de Oxycraspedus Kuschel (Coleóptera: Belidae en Argentina y uso de un modelo predictivo para comparar su distribución potencial con el rango de su planta huésped, la Araucaria araucana

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    M.S. FERRER

    2007-09-01

    Full Text Available The first records of the three known species of Oxycraspedus Kuschel (Belidae: Oxycoryninae in Argentina are reported, and added to their known distribution in Chile. These weevils are of interest because of their association with the pehuén or monkey puzzle tree, Araucaria araucana, a species of conservation concern. Their distribution data are of value for the protection of biodiversity in natural areas of Patagonia. The potential distribution of Oxycraspedus, as predicted by a model using bioclimatic variables, is coincident as expected, with the geographic range of the araucaria host-plantSe reportan por primera vez en Argentina las tres especies de Oxycraspedus Kuschel (Belidae: Oxycoryninae y se añaden a su distribución en Chile. Estos gorgojos son de interés debido a su asociación con el pehuén Araucaria araucana, una especie de gran interés en temas de conservación. Los datos sobre su distribución son valiosos para proteger la biodiversidad en áreas de la Patagonia. La distribución potencial de Oxycraspedus predicha por un modelo a partir de variables bioclimáticas, es coincidente, como se esperaba, con el rango geográfico de su planta huésped, la araucaria

  18. Paleoecología: el uso de los quironómidos fósiles (Diptera: Chironomidae en reconstrucciones paleoambientales durante el Cuaternario en la Patagonia

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    Julieta MASSAFERRO

    2009-01-01

    Full Text Available Entre los indicadores biológicos lacustres más utilizados en las reconstrucciones ambientales, se encuentran el polen, los ostrácodos y las diatomeas, y entre los insectos, los coleópteros y los quironómidos. Este grupo ha cobrado gran importancia en los últimos tiempos, debido a los resultados prometedores que se han obtenido en reconstrucciones climáticas realizadas en América del Norte y Europa. En América del Sur, el uso de los quironómidos fósiles en estudios cuaternarios es relativamente limitado, principalmente por su escaso conocimiento taxonómico regional. La mayor parte de estos estudios fueron realizados en lagos glaciares patagónicos de Argentina y Chile. Las larvas de quironómidos constituyen una valiosa herramienta paleolimnológica, por ser un grupo de organismos altamente sensible a cambios ambientales, tanto naturales como artificiales. Además, es un grupo de insectos ampliamente distribuido y con una abundancia y diversidad relativamente altas. Sus cápsulas cefálicas se preservan en los sedimentos lacustres y poseen caracteres importantes que permiten identificar géneros y muchas veces especies. El estudio de los ensambles de quironómidos en sedimentos lacustres puede ser utilizado con distintos objetivos, por ejemplo, para estudios de eutrofización, ya que responden rápidamente a cambios en la concentración de nutrientes, materia orgánica y otros elementos, como metales pesados. No obstante, uno de los potenciales más importantes de este grupo de insectos es su sensibilidad a los cambios de temperatura, por este motivo, la aplicación más importante de su estudio en sedimentos se centra en las reconstrucciones climáticas. Esta contribución es una síntesis de los resultados de los trabajos publicados en la Patagonia argentina y chilena, sobre la base del uso de los quironómidos fósiles en reconstrucciones paleoambientales.

  19. Diversidad de helechos y licofitas del Parque Nacional Lago Puelo (Chubut-Argentina Diversity of ferns and licophytes of the National Park Lago Puelo (Chubut- Argentina

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    Liliana A. Cassá de Pazos

    2010-12-01

    Full Text Available Se estudiaron los helechos y licofitas presentes en el Parque Nacional Lago Puelo, Chubut, Argentina. Se determinó la presencia de 47 taxa, de los cuales 12 constituyen nuevos registros para la Provincia de Chubut y 1 para la Región Patagónica. Se observó una elevada diversidad taxonómica, representando más del 50 % de la flora patagónica. Varios de los taxa crecen exclusivamente en el área y en Chile a iguales latitudes. El paso Puelo, que conecta Argentina y Chile, es el más bajo de la Cordillera de los Andes en Norpatagonia y es vía de ingreso de especies valdivianas. La presencia de animales de pastoreo, invasión de plantas exóticas y el riesgo latente de incendios, significan un peligro para la supervivencia de la flora del Parque. Todas estas características hacen que estas áreas de los Bosques Subantárticos merezcan una especial atención para su conservación. Se presentan claves para la determinación de los taxa y un mapa de ubicación de las áreas de mayor diversidad de helechos y licofitas dentro del parque. Para cada taxón registrado se da la distribución geográfica y datos ecológicos en el área de estudio.The ferns and licophytes from the National Park Lago Puelo, Chubut, Argentina were studied. We registered 47 taxa with 12 of them new records for the province of Chubut and 1new to Patagonia. A high taxonom-ic diversity was observed, with about 50 % of the Patagonian fern flora represented. Some of the taxa are growing exclusively in this area and in Chile at the same latitudes. The Puelo pass, which is connect-ing Argentina and Chile, at the lowest altitude of the North- Patagonian Andes, constituted a penetrating route of Valdivian species. The presence of pasture livestock, the invasion of exotic plants and the latent fires, are the principals dangers for the survival of the Flora in this area. Therefore these areas of the Subantartic Forest merit special attention for conservation. A taxonomic key is

  20. Health at the time of Native-European contact in Southern Patagonia: First steps, results, and prospects

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    Ricardo Aníbal Guichón

    2006-12-01

    Full Text Available The objective of this paper is to present the first steps into the study of health in southern Patagonia during pre and post Native-European contact. Thus, our work has a double purpose. First, to discuss characteristics and relevance of human bone records of southern Patagonia, in order to study health in a population context. Second, to show some new lines of information, which include paleoparasitology, nutritional paleopathologies, and the study of lifestyles from human remains. In this context, we have started working on the first Spanish settlement "Nombre de Jesus", founded in 1584, and with historical documentation of "La Candelaria" Mission in Rio Grande (1896-1931.

  1. Area Handbook Series: Argentina: A Country Study

    Science.gov (United States)

    1985-08-01

    Etchepareborda, Roberto, Ricardo M. Ortiz, and Juan V. Orona, La crisis de 1930: Ensayos (I). ( Biblioteca Politica Argentina, 15.) Buenos Aires: Centro...Roots of Dependency in Peru and Argentina. Boulder: Westview Press, 1984. Gambini, Hugo. Las presidencias peronistas: La primera pre- sidencia de...in Bagü Pinedo et al, (eds.). La crisis de 1930: Testimonios (H). Argentina: Biblioteca Politica Argentina, 1983. Goldwert, Marvin. Democracy

  2. Coccocypselum pulchellum (Rubiaceae, nuevo registro para Argentina

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    Elsa L. Cabral

    2007-01-01

    Full Text Available Se cita Coccocypselum pulchellum por primera vez para Argentina, en Predio Guaraní, Misiones. Esta es la tercera especie de Coccocypselum registrada para la flora de Argentina junto con C. hasslerianum y C. lanceolatum. Se incluyen descripciones, ilustraciones y una clave para reconocer las tres especies argentinas de Coccocypselum.

  3. Outburst floods of glacial lakes in Patagonia: is there an increasing trend?

    Science.gov (United States)

    Casassa, Gino; Wendt, Jens; Wendt, Anja; López, Paulina; Schuler, Thomas; Maas, Hans-Gerd; Carrasco, Jorge; Rivera, Andrés.

    2010-05-01

    Glaciers in Patagonia are temperate and many of them are receding at an accelerated rate, with a consequent enlargement of glacial lakes. We will review the occurrence of Glacial Lake Outburst Floods (GLOFs) recorded during the last century in Patagonia (Northern and Southern Patagonia icefields), and analyse them in view of the general warming of 0.5°C affecting the region during the last 40 years. Special attention will be devoted to Lake Cachet 2 (47°12' S, 73°15' W, 422 m a.s.l.) which has experienced 6 GLOF events during the last 2 years: April 6-7 2008, October 7-8 2008, 21-22 December 2008, 5 March 2009, 16 September 2009 and 5-6 January 2010. Lake Cachet 2 has an area of 4 km2, located on the eastern margin of the Northern Patagonia Icefield, being dammed on its southern margin by Colonia Glacier. Prior to the April 2008 event there had been no historical record of catastrophic flooding of this lake. Each event resulted in a flood wave of which travelled down Colonia River to the confluence with Baker River in a period of less than 48 hours, where it reached peak flows of approximately 2,000 m3/s. Here we present airborne and ground explorations carried out in the period 2008-2009 which confirm that the Lake Cachet 2 floods drain through an englacial tunnel under Colonia Glacier for a distance of 8 km, emerging at the front of the glacier. We propose that the lake started draining in 2008 as a result of the weakening of the ice dam produced by long-term thinning of Colonia Glacier. Measurements of the empty lake bed were performed with the CECS airborne laser scanner onboard a helicopter, which show that the maximum water volume of the lake is 200 x 106 m3. Modelling of the flood events has been carried out based on the subglacial flood model of Clarke (2003), showing that a semi-circular subglacial tunnel attaining a maximum dimension of 15 m can evacuate Lake Cachet 2 in approximately 48 hours, with peak flows on the order of 4000 m3/s. Preliminary

  4. Los mallines en Patagonia: una perspectiva histórico cultural de los recursos naturales

    OpenAIRE

    Alexandra Bruce; Ana Cecilia Dufilho

    2002-01-01

    El presente estudio es parte de un proyecto marco implementado por la Cátedra de Hidráulica e Hidrología Agrícola de la Facultad de Ciencias Agrarias y de la Cátedra de Riego y Drenaje del Asentamiento Universitario San Martín de los Andes, ambos de la Universidad Nacional del Comahue, que tiene como eje los estudios hidrológicos asociados a los mallines y a los recursos hídricos de la Patagonia. Se partió con la convicción que la historia y la cultura social, resultan los factores indisp...

  5. Amaryllidaceae adventicias en la Argentina Amaryllidaceae adventitious in Argentina

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    Julio A. Hurrell

    Full Text Available Este trabajo incluye el estudio de las Amaryllidaceae adventicias para la Argentina, representadas por 4 géneros: Amaryllis, Crinum, Leucojum y Narcissus y 6 especies, 3 de ellas son nuevas citas: Crinum asiaticum , Leucojum aestivum y Narcissus poeticus ; y se actualizan los datos disponibles sobre Amaryllis belladonna , Crinum x powellii y Narcissus tazetta .This paper includes an abstract for adventive Amaryllidaceae for Argentina, 4 genera are represented: Amaryllis, Crinum, Leucojum and Narcissus, with 6 species; 3 of them are new records: Crinum asiaticum, Leucojum aestivum and Narcissus poeticus ; and updated observations of the previously cited: Amaryllis belladonna , Crinum x powellii and Narcissus tazetta.

  6. Crisis de la prensa Argentina

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    Federico Rey Lennon

    2015-01-01

    Full Text Available La magnitud de la crisis económica Argentina es enorme y difícil saber hasta cuando se extenderá, agravada por una situación política frágil. La actual recesión ha hecho caer la inversión publicitaria a los niveles más bajos de los últimos años. De 1997 al 2001 la circulación de la prensa Argentina cayó en el 36 por ciento. El riesgo en Argentina es la eventual extranjerización de casi todos los medios de comunicación.

  7. Cuerpos para experimentar. Objetivación médica, positivismo y eliminación étnica en Argentina (1860-1890

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    Di Liscia, María Silvia

    2002-06-01

    Full Text Available This paper analises the ways used by the physicians to support scientifically the inferior condition of the native people of the Pampa and Patagonia. Several physicians, like Paolo Mantegazza, Benjamin Dupont, José Franceschi and Lucio Meléndez, had a typical positivist ideology about the middle of the XIXª Century in Argentina, conected with the aplication of the biological theory for the elimination of native people.

    Este trabajo analiza los mecanismos utilizados por determinados especialistas en medicina para determinar científicamente la inferioridad de las etnias nativas, especialmente las de la Pampa y Patagonia. Se trata de un fenómeno común al pensamiento posivista argentino de la segunda mitad del siglo XIX que se refleja fundamentalmente en los trabajos de varios médicos, como Paolo Mantegazza, Benjamín Dupont, José Franceschi y Lucio Meléndez, cuyo discurso ejemplifica el etnocentrismo y la aplicación de teorías biologicistas en el ámbito nacional, consecuentes con el exterminio paralelo de los indígenas.

  8. División social del espacio residencial y migraciones: El caso de San Carlos de Bariloche, Argentina

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    Brenda Matossian

    2015-09-01

    Full Text Available El espacio intraurbano en las ciudades contemporáneas de América Latina acusa profundas divisiones sociales, dado el tipo de desarrollo que han tenido bajo los modelos neoliberales imperantes. En este artículo se analiza la ciudad como parte de un devenir histórico-político particular, desde un enfoque multidimensional en el que se hace especial énfasis en la relación establecida entre las divisiones territoriales internas y el componente migratorio de la población. San Carlos de Bariloche (Patagonia argentina posee una heterogénea composición étnico-cultural, fruto de diversos flujos migratorios internos e internacionales. Profundas y complejas distancias materiales y simbólicas separan la ciudad turística (la "Suiza argentina" asociada a una elite nutrida por migrantes internos urbanos y europeos, de la ciudad de "El Alto", donde migrantes internos rurales y chilenos se han asentado en barrios populares. La relación clase-origen se entrelaza en una división social del espacio residencial, que se profundiza y produce segregación urbana y refuerza las tensiones.

  9. New postcranial remains of large toxodontian notoungulates from the late Oligocene of Mendoza, Argentina and their systematic implications

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    Santiago Hernández Del Pino

    2017-03-01

    Full Text Available During the last decade, the Deseadan (late Oligocene Quebrada Fiera locality, Mendoza Province, Argentina, has provided a large amount of mammal remains. Taxonomic studies have shown the presence of faunal elements common with other Deseadan associations from Patagonia and lower latitudes (Salla, Bolivia, as well as endemic taxa of different groups of mammals (Notohippidae, Leontiniidae, Homalodotheriidae, Hegetotheriidae, and Metatheria and even a gastropod. In this work, we present a taxonomic and phylogenetic analysis of a set of postcranial fossils of three families of the suborder Toxodontia (Notoungulata. The postcranial elements are assigned to taxa previously recognized at Quebrada Fiera, such as the leontiniid Gualta cuyana and the homalodotheriid Asmodeus petrasnerus, but also to the family Toxodontidae that is represented by Proadinotherium sp. and another larger toxodontid; a few dental remains of Proadinotherium are also included as this is the first time that toxodontids from Quebrada Fiera are described. In the case of A. petrasnerus, an almost complete calcaneum allows us to expand the diagnosis of this taxon. The bones assigned to G. cuyana enlarge the anatomical knowledge of this species. In turn, the presence of the genus Proadinotherium extends its geographic distribution in Argentina and adds to the extra-Patagonian record of P. saltoni from Salla, Bolivia. Phylogenetic results do not differ much from previous analyses using postcranial characters, and the obtained consensus trees show low node supports. The various phylogenetic analyses performed here provide a more robust framework to interpret the relationships of the studied taxa.

  10. Diet composition and feeding habits of the eyespot skate, Atlantoraja cyclophora (Elasmobranchii: Arhynchobatidae, off Uruguay and northern Argentina

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    Santiago A. Barbini

    Full Text Available ABSTRACT The eyespot skate, Atlantoraja cyclophora, is an endemic species from the southwestern Atlantic, occurring from Rio de Janeiro, Brazil, to northern Patagonia, Argentina. The feeding habits of this species, from off Uruguay and north Argentina, were evaluated using a multiple hypothesis modelling approach. In general, the diet was composed mainly of decapod crustaceans, followed by teleost fishes. Molluscs, mysidaceans, amphipods, isopods, lancelets and elasmobranchs were consumed in lower proportion. The consumption of shrimps drecreased with increasing body size of A. cyclophora. On the other hand, the consumption of teleosts increased with body size. Mature individuals preyed more heavily on crabs than immature individuals. Teleosts were consumed more in the south region (34º - 38ºS and crabs in the north region (38º - 41ºS. Shrimps were eaten more in the warm season than in the cold season. Prey size increased with increasing body size of A. cyclophora , but large individuals also consumed small teleosts and crabs. Atlantoraja cyclophora has demersal-benthic feeding habits, shifts its diet with increasing body size and in response to seasonal and regional changes in prey availability and distribution.

  11. The Odonata (Insecta) of Patagonia: a synopsis of their current status with illustrated keys for their identification.

    Science.gov (United States)

    Muzón, Javier; Pessacq, Pablo; Lozano, Federico

    2014-03-31

    Patagonia is a vast landmass with a distinctive environmental and biotic heterogeneity. Its Odonata biodiversity is the best known of South America, and it is composed of 36 species, of which more than 50% are endemic. We summarize the main taxonomic, distributional and biological information including illustrated keys for adults and known larvae, and distributional maps.

  12. Inter-subjectivity and Domestication in the Making of a Global Region: Territorialization of Salmon in the Chilean Patagonia.

    NARCIS (Netherlands)

    Blanco, Gustavo; Arce, A.M.G.; Fisher, E.F.

    2016-01-01

    This article examines transformations in the Chilean Patagonia, a region that has become a world leader in Salmon production for global markets. Employing ethnographic methods, this study examines the possibilities of considering inter-subjectivities in the processes of conforming important regions

  13. Tandil, Buenos Aires, Argentina

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    María L. Bakker

    2006-01-01

    Full Text Available Se coleccionaron hojas maduras de ejemplares adultos de Populus alba, Populus deltoides, Robinia pseudoacacia, Ulmus pumila y Fraxinus americana del Campus Universitario, Tandil, Buenos Aires, Argentina (37° 19’S, 59° 08’O en febrero de 2004. La cera cuticular fue extraída, purificada, y el contenido y proporción relativa de n-alcanos de número impar de carbonos (C23C35 fue cuantificado mediante cromatografía gas-líquido capilar. La concentración total de n-alcanos (mg/kg MS fue P. alba (6935 > Robinia (1571 > P. deltoides (1379 > Ulmus (880 > Fraxinus (467. Los n-alcanos más abundantes en todas las especies fueron C27 y C29 que constituyeron entre 10 y 51% y entre 35 y 76% del total respectivamente, excepto en Fraxinus donde los más abundantes fueron C29 y C31 que constituyeron el 31 y 49% del total respectivamente. P. alba y P. deltoides difirieron no solo en la concentración total de n-alcanos sino también en la proporción relativa de C27 y C29, siendo C29 el n-alcano más abundante en la segunda especie (76% igual que en Robinia (75%. La presencia de nalcanos de número par de carbonos no fue detectable o resultó muy baja en general en todas las especies, con excepción de C26, C28 y C30, este último se destacó particularmente en Fraxinus.

  14. Episodic Jurassic to Lower Cretaceous intraplate compression in Central Patagonia during Gondwana breakup

    Science.gov (United States)

    Navarrete, César; Gianni, Guido; Echaurren, Andrés; Kingler, Federico Lince; Folguera, Andrés

    2016-12-01

    From Lower Jurassic to Lower Cretaceous, several intraplate compression events affected discrete sectors of Central Patagonia, under a general context of crustal extension associated with Gondwana breakup. This was demonstrated by means of 2D and 3D seismic and borehole data, which show partial inversion of Lower and Middle Jurassic extensional structures of the Chubut and Cañadón Asfalto basins, during the earliest stages of breakup. A comparison with surrounding areas in Patagonia, where similar Jurassic intraplate compression was described, allowed the discrimination of three discrete pulses of subtle compression (C1: ∼188-185 Ma; C2: ∼170-163; C3: ∼157-136? Ma). Interestingly, episodic intraplate compressional events are closely followed by high flux magmatic events linked to the westward expansion of the Karoo-Ferrar thermal anomaly, which impacted on the lithosphere of southwest Gondwana in Lower Jurassic. In addition, we determined the approximate direction of the main compressive strain (σ1) compatible with other Jurassic intraplate belts of South America. These observations led us to propose a linkage between a thermo mechanically weakened continental crust due to LIPs activity, changes in plate motions and ridge-push forces generated by the opening of the Weddell Sea, in order to explain intraplate shortening, interrupted while Karoo LIPs magmatic invigoration took place.

  15. Solar ultraviolet radiation and its impact on aquatic systems of Patagonia, South America

    Energy Technology Data Exchange (ETDEWEB)

    Villafane, Virginia E.; Helbling, E. Walter [Estacion de Fotobiologia Playa Union, Trelew, Chubut (Argentina); Zagarese, Horacio E. [Univ. Nacional del Comahue, San Carlos de Bariloche, Rio Negro (Argentina). Centro Regional Universitario Bariloche

    2001-03-01

    Solar ultraviolet radiation (UVR, 280-400 nm) is known to cause a number of detrimental effects in aquatic organisms. The area of Patagonia, which is sometimes under the influence of the Antarctic ozone 'hole', occasionally receives enhanced levels of ultraviolet B radiation (UV-B, 280-315 nm). Great efforts have been put into creating a database for UVR climatology by installing a variety of instruments in several localities in the region. However, no comparable effort has been made to determine the impact of normal and enhanced levels of solar UVR upon organisms. Most of the photobiological research in aquatic systems of Patagonia has focused on determining the effects of solar UVR in phytoplankton photosynthesis, DNA damage, and mortality, fecundity and repair mechanisms in zooplanktonic species. Some work has also been done with fish larvae and interactions between species at low trophic levels of the aquatic food web. The results of these studies indicate that in order to assess the overall impact of UVR in a certain water body, it is also necessary to consider other variables, such as changes in cloudiness, ozone concentrations, differential sensitivity of organisms, and depth of the upper mixed layer/epilimnion. All factors that can preclude or benefit the acclimation of species to solar radiation.

  16. PALEOCLIMAS Y PALEOESCENARIOS EN LA PATAGONIA AUSTRAL Y EN TIERRA DEL FUEGO DURANTE EL CUATERNARIO

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    Andrea Coronato

    2007-12-01

    Full Text Available Se presentan evidencias geomorfológicas y palinológicas indicadoras de paleoescenarios existentes en los últimos dos millones de años en el extremo sur de Patagonia y Tierra del Fuego. Estos procesos indican la ocurrencia de cambios climáticos no forzados por intervención humana en la atmósfera. Los períodos fríos habrían sido progresivamente menos intensos desde la Gran Glaciación Patagónica, ocurrida hace 1 millón de años. Durante el Holoceno y los tiempos históricos, las glaciaciones se restringieron a las zonas superiores a los 900 m s.n.m. y el deterioro climático no habría afectado significativamente al ecosistema bosque ubicado a menos de 400 m s.n.m. Un importante período cálido ocurrido en tiempos históricos fue registrado en las zonas de altura en Patagonia Norte y en las cercanías al nivel del mar en Tierra del Fuego

  17. Saccharomyces eubayanus and Saccharomyces uvarum associated with the fermentation of Araucaria araucana seeds in Patagonia.

    Science.gov (United States)

    Rodríguez, M Eugenia; Pérez-Través, Laura; Sangorrín, Marcela P; Barrio, Eladio; Lopes, Christian A

    2014-09-01

    Mudai is a traditional fermented beverage, made from the seeds of the Araucaria araucana tree by Mapuche communities. The main goal of the present study was to identify and characterize the yeast microbiota responsible of Mudai fermentation as well as from A. araucana seeds and bark from different locations in Northern Patagonia. Only Hanseniaspora uvarum and a commercial bakery strain of Saccharomyces cerevisiae were isolated from Mudai and all Saccharomyces isolates recovered from A. araucana seed and bark samples belonged to the cryotolerant species Saccharomyces eubayanus and Saccharomyces uvarum. These two species were already reported in Nothofagus trees from Patagonia; however, this is the first time that they were isolated from A. araucana, which extends their ecological distribution. The presence of these species in A. araucana seeds and bark samples, led us to postulate a potential role for them as the original yeasts responsible for the elaboration of Mudai before the introduction of commercial S. cerevisiae cultures. The molecular and genetic characterization of the S. uvarum and S. eubayanus isolates and their comparison with European S. uvarum strains and S. eubayanus hybrids (S. bayanus and S. pastorianus), allowed their ecology and evolution us to be examined. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  18. Argentina: Nationality, Demography and Security

    Science.gov (United States)

    1993-04-22

    improve the industries, and introduce and teach both sciences and arts". Reform would aim at selecting immigrants. Reviewing Argentine history S•d the...1978. 4. Palacio H. "Historia de la Argentina", Ed. Pefiatillo, Buenos Aires, 1973. 5. Randle, P.H. and others. "La Conciencia Territorial Ed. Oikos

  19. Sessea regnellii (Solanaceae en Argentina

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    Héctor A. Keller

    2006-01-01

    Full Text Available Se cita por primera vez a Sessea regnelli para la flora argentina. Se presenta una descripción de la especie sobre la base de los ejemplares examinados, como así también ilustraciones y observaciones ecológicas.

  20. Respuesta dietaria de tres rapaces frente a una presa introducida en Patagonia Dietary response of three raptor species to an introduced prey in Patagonia

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    ANA L. MONSERRAT

    2005-09-01

    Full Text Available Los depredadores de marcada respuesta funcional pueden poseer la capacidad de estabilizar las poblaciones de sus presas, lo cual es destacable en el caso de presas introducidas, que suelen causar impactos negativos en los ecosistemas nativos y las actividades agropecuarias. La situación actual de la Patagonia es crítica respecto a la introducción de especies. Estudios previos indican que los depredadores nativos exhiben un cambio general en sus dietas debido a la introducción de presas exóticas que están reemplazando a sus presas originales. Determinamos los hábitos alimenticios del águila (Geranoaetus melanoluecus, el búho magallánico (Bubo magellanicus y el aguilucho común (Buteo polyosoma, tres de las principales aves depredadoras de la liebre europea (Lepus europaeus, introducida en el noroeste de Patagonia. Para esto analizamos 321, 115 y 78 egagrópilas de águila, búho y aguilucho respectivamente. Evaluamos las respuestas funcionales a la densidad de liebre europea y comparamos las dietas entre sitios diferentes. Las principales presas del aguilucho y del búho fueron los roedores sigmodontinos y en segundo lugar los tuco-tucos (Ctenomys spp.. El águila consumió principalmente liebres y en segundo lugar tuco-tucos, presentando una respuesta funcional significativa para la presa introducida. La dieta de este rapaz fue diferente entre sitios con alta y baja densidad de liebres. Para los otros dos rapaces no encontramos una respuesta funcional significativa para la liebre europea, pero la dieta del aguilucho varió en función del sitio geográfico. Concluimos que tanto el águila mora como el aguilucho se alimentan de manera generalista, siendo el búho el único de los tres rapaces con tendencia especialista sobre pequeños roedores. Por otra parte, la variación de la dieta del águila en función de la densidad de liebre europea le brinda el potencial de contribuir a la regulación de las poblaciones de la misma

  1. Nueva especie de Planorbidae (Gastropoda: Basommatophora en la Patagonia chilena: Biomphalaria cristiani sp. nov. First record of Planorbidae (Mollusca: Basommatophora in Chilean Patagonia: Biomphalaria cristiani sp. nov.

    Directory of Open Access Journals (Sweden)

    Carmen Fuentealba

    2012-11-01

    Full Text Available En Chile la familia Planorbidae está representada por el género Biomphalaria Preston, 1910, compuesta por siete especies distribuidas desde Isluga hasta el río Puelo. De estas especies, solo B.peregrina, ampliamente distribuida en el neotrópico, y Biomphalaria aymara de Isluga, han sido reconocidas sobre la base de la morfología del sistema reproductor y la rádula, caracteres que fueron utilizados en el presente estudio para diferenciar a Biomphalaria cristiani como nueva especie del grupo y primer registro de la familia en la Patagonia chilena, ampliando su actual rango de distribución. Los caracteres que permiten la diagnosis de B. cristiani son el saco vaginal vestigial truncado, ausencia del desarrollo de los músculos suspensores del pene, vaina del pene corta en relación al prepucio, oviducto largo en relación al espermioducto y vaso deferente más delgado y largo que la vaina del pene, de tamano similar al prepucio. La localidad tipo de Biomphalaria cristiani sp. nov. es Laguna Cisnes (47°7'10.02"S, 72°27'40.65"W, región de Aysén.The family Planorbidae in Chile is represented by the genus Biomphalaria Preston, 1910, consisting of seven species distributed from Isluga to Puelo River. Of these species, only Biomphalaria peregrina widely distributed in the neotropical and Biomphalaria aymara from Isluga are recognized based on the morphology of the reproductive system and radula, characters that were used in the following study to differentiate Biomphalaria cristiani as a new species of this group and first record of the family in Chilean Patagonia, extending its current distribution range. The characters for the diagnosis of B. cristiani are: truncated vestigial vaginal pouch, lack of development of the penis retractor muscles, penis sheath shorter than the prepuce, oviduct longer than the spermiduct and vas deferens thinner and longer than the penis sheath, similar size to the prepuce. The type locality of B. cristiani nov. sp

  2. Discursos de alteridad en la dramaturgia regional de la posdictadura argentina

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    Mauricio Tossi

    2016-01-01

    Full Text Available Las secuelas de la última dictadura militar en Argentina se observan en diversos aspectos culturales, entre otros, en la concepción de “alteridad sospechosa” que el régimen instaló en los campos sociales para justificar sus políticas represivas y genocidas. De este modo, con la reapertura democrática, el arte en general y el teatro en particular, asumieron, con responsabilidad estética, la tarea de resignificar aquellos discursos sobre la otredad ominosa legada. Por consiguiente, en el presente artículo abordaremos las respuestas poé- ticas que la dramaturgia regional ha enunciado como estrategias de resistencia, con el fin de aportar a los nuevos procesos comunitarios e intersubjetivos sobre el pasado reciente. Para indagar en este problema, apelaremos a herramientas hermenéuticas de la literatura comparada y la sociología de la cultura, aplicadas al análisis de las obras teatrales de Alejandro Finzi y Carlos María Alsina, escritas en la Patagonia y el noroeste argentinos, en el periodo1983-2003.

  3. Paleoparasitologia en coprolitos del Parque Nacional Perito Moreno, provincia de Santa Cruz, Argentina

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    Fugassa, Martín H.

    2005-01-01

    Full Text Available El objetivo del trabajo fue conocer algunas de las parasitosis que existían en América precolombina y discutir diversos aspectos ecológico-culturales. El coprolito examinado provino del sitio Cerro Casa de Piedra 5 (CCP5, Parque Nacional Perito Moreno, Santa Cruz, Argentina. Las muestras fueron rehidratadas con fosfato trisódico acuoso y procesadas por sedimentación espontánea. Existieron dificultades para la determinación del origen zoológico del coprolito-cánido o humano-y el análisis de los restos macroscópicos y pelos presentes resultó decisivo. Los resultados evidenciaron un caso de poliparasitismo entre los que se hallaron huevos correspondientes al género Trichuris y a especies del género Capillaria. Otros hallazgos corresponden a huevos atribuibles a ascarididos, eucestodes y ooquistes de coccidios. Se hallaron huevos que no pudieron determinarse si correspondían a ácaros o pentastómidos. La muestra analizada ha aportado información inédita sobre el parasitismo en Patagonia Austral precolombina. Se discute su significado bioantropológico. Los resultados presentados permiten demostrar el valor de la recuperación de coprolitos y sedimentos arqueológicos.

  4. Sauropod and theropod dinosaur tracks from the Upper Cretaceous of Mendoza (Argentina): Trackmakers and anatomical evidences

    Science.gov (United States)

    González Riga, Bernardo Javier; Ortiz David, Leonardo Daniel; Tomaselli, María Belén; dos Anjos Candeiro, Carlos Roberto; Coria, Juan Pedro; Prámparo, Mercedes

    2015-08-01

    New findings of dinosaur ichnites from Agua del Choique section (Mendoza Province, Argentina) provides ichnological and anatomical information about the Cretaceous sauropods and theropods. Around 330 tracks distributed in six footprint levels were identified in this area, one of most important of South America. Two ichnocenoses are located in different paleoenvironmental contexts. In the Anacleto Formation (early Campanian) around 20 titanosaurian tracks were found in floodplain and ephemeral channel deposits. Herein, one pes track shows three claw impressions and this is congruent to two new titanosaur specimens recently discovered in Mendoza Province that have articulated and complete pedes. In this context, for the first time to titanosaurs, ichnological evidences are supported by skeletal elements. In the Loncoche Formation (late Campanian-early Maastrichtian) titanosaurian tracks of Titanopodus mendozensis are abundant (around 310 tracks) and were produced by titanosaurs that walked in a very wet substrate of tidally dominated deltas related with the first Atlantic transgression for northern Patagonia. In this facies association, three different trydactl tracks indicate the presence of small theropods (1-2 m long), expanding the knowledge about the faunistic components that lived in these marine marginal environments.

  5. Mapuche y ranqueles en la Argentina: relatos sobre su pasado y presente

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    Graciana Pérez Zavala

    2008-07-01

    Full Text Available En este artículo se planteo la reconstrucción de los relatos del pasado por parte de indígenas que viven en el territorio argentino, particularmente los mapuche y ronqueles. Para explicar estos variaciones en la interpretación del pasado por parte de las diferentes organizaciones indigenas, se examina la "Conquista del Desierto" (1878-1885, en tanto acontecimiento nodal en la estructuración de las relaciones interétnicas actuales en Argentina. En primer lugar, se sintetizan varios elementos de la historia de los indígenas de Pampa y Patagonia en los años previos a su sometimiento. Posteriormente, se describen los acontecimientos ligados a la "Conquista del Desierto", teniendo en cuenta al Estado argentino y a las diferentes "tribus". Luego, se caracteriza la situación de los indigenas después de 1885, y para finalizar, se analizan los relatos de los mapuche y ranqueles contemporaneos en el marco de su resurgimiento como pueblos preexistentes al Estado Nacional argentino.

  6. Chemical and Antioxidant Properties of Wild Edible Mushrooms from Native Nothofagus spp. Forest, Argentina.

    Science.gov (United States)

    Toledo, Carolina V; Barroetaveña, Carolina; Fernandes, Ângela; Barros, Lillian; Ferreira, Isabel C F R

    2016-09-08

    This study addresses issues regarding chemical and bioactive properties of nine wild edible mushrooms from native Nothofagus forest from Patagonia, Argentina. Macronutrients, sugars, fatty acids, tocopherols, organic acids, phenolic compounds and antioxidant properties were determined. Protein was found in high levels and varied between 3.35 g/100 g dw in Cyttaria hariotii and 22.29 g/100 g dw in Lepista nuda. All of them presented mannitol and trehalose as main sugars. Mannitol was significantly higher in Ramaria patagonica, although absent in Fistulina endoxantha, whereas trehalose predominated in Aleurodiscus vitellinus, Hydropus dusenii, Cortinarius magellanicus, C. hariotii, Grifola gargal and L. nuda, ranging from 1.15 to 10.26 g/100 g dw; it was absent in R. patagonica. The major fatty acid found was linoleic acid, followed by oleic acid and palmitic acid. All species presented oxalic and fumaric acids, while some also had malic, quinic and citric acids. Tocopherols composition was variable. Cortinarius magellanicus presented significantly higher contents of both α-tocopherol and β-tocopherol. R. patagonica presented the best results in all the antioxidant activity assays (EC50 values ≤ 1 mg/mL) and the highest content of phenolic compounds presenting gallic, p-hydroxybenzoic, p-coumaric and cinnamic acids. This study constitutes the first report on chemical composition and nutritional value of most of these edible mushroom species. Furthermore, it provides important information necessary to characterize and define the use of these species as gastronomic delicacies, functional foods and sources of bioactive compounds.

  7. Levaduras fermentadoras aisladas de Cyttaria hariotii (Fungi en bosques Andino-Patagónicos (Argentina Fermenting yeasts isolated from Cyttaria hariotii (Fungi in the Andean Patagonic Forest

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    José Ulloa

    2009-12-01

    Full Text Available Las levaduras han estado asociadas al hombre desde épocas muy tempranas. Entre estas se destacan las fermentadoras debido a su importancia en la industria de los alimentos. Las implicancias biotecnológicas de estas levaduras han sido extensamente estudiadas, sin embargo la distribución en la naturaleza y la ecología de estas no se encuentra igualmente documentada. El presente estudio se realizó en el Parque Nacional Nahuel Huapi (Noroeste Patagónico, Argentina sobre Cyttaria hariotii, hongo ascomicético parásito de árboles del género Nothofagus. Mediante el uso de un medio selectivo con etanol 8 % se obtuvieron 72 aislamientos. Los mismos fueron ordenados en cinco grupos en base a pruebas morfológicas y fisiológicas, tres de los cuales fueron asignados a los géneros Saccharomyces, Pichia y Kloeckera. El grupo Saccharomyces presentó el mayor número de aislamientos y se subdividió en tres subgrupos, dos de ellos presentan alta afinidad con S. bayanus y/ó S. uvarum. La totalidad de los aislamientos fueron psicrotolerantes y la temperatura máxima de crecimiento osciló entre 35 y 37 _C. El presente trabajo contribuye al conocimiento de la biodiversidad de levaduras de la Patagonia y representa el primer aislamiento masivo de levaduras sacaromicéticas en ambientes naturales de la región.Yeasts have been associated with mankind from early ages. Among these, fermentative yeasts played the most relevant role, due to its importance in the food industry. The biotechnological implications of these yeasts have been extensively studied. However there is a lack of information about its distribution in nature and ecology. In this study samples of Cyttaria hariotii, ascomycete fungus parasite of trees of the genus Nothofagus, were collected in Nahuel Huapi National Park (Northwestern Patagonia, Argentina. 72 isolates were obtained using a selective culture medium with 8% ethanol. Identification of the isolates was based on morphological and

  8. Una tortuga Chelidae (Testudines: Pleurodira de cuello largo en el Grupo Neuquén, Río Negro, Argentina: Significado cronológico y paleobiogeográfico A long-necked Chelidae turtle (Testudines: Pleurodira from the Neuquén Group, Río Negro, Argentina: Chronological and paleobiogeographical significance

    Directory of Open Access Journals (Sweden)

    Marcelo S de la Fuente

    2010-07-01

    Full Text Available Diferentes restos de una tortuga Chelidae cuellilarga de la Formación Anacleto (Santoniano tardío-Campaniano temprano, aflorante en la localidad de Valle de la Luna Rojo, Provincia de Río Negro, Argentina, son conferidos a la especie Yaminuechelys cf. gasparinii De la Fuente, De Lapparent de Broin y Manera de Bianco, 2001. Ellos representan el registro más antiguo para el género y los Chelidae de cuello largo. Se sugiere que el ancestro común de Yaminuechelys e Hydromedusa habitó en Gondwana meridional con anterioridad a la separación de Australia. La presencia de este taxón en el Cretácico Tardío en Patagonia y algunos de los resultados de los análisis filogenéticos previos apoyan la hipótesis sobre una temprana diferenciación y diversificación de los quélidos en dicha región de Gondwana.A long necked chelid turtle species from the Anacleto Formation (late Santonian-early Campanian cropping out at Valle de La Luna Rojo, Río Negro Province, Argentina, is assigned to Yaminuechelys cf. gasparinii De la Fuente, De Lapparent de Broin and Manera de Bianco, 2001 and it represents the oldest record of a long-necked chelid. We suggest that the common ancestor of Yaminuechelys and Hydromedusa lived in Southern Gondwana before the separation of Australia from the remaining Southern Gondwanan landmasses. The presence of this chelid taxon in the Late Cretaceous of Patagonia and some previous phylogenetic analyses support the hypothesis of an early differentiation and diversification of chelids on Southern Gondwana.

  9. Timing of the deglaciation in southern Patagonia: Testing the applicability of K-Feldspar IRSL

    DEFF Research Database (Denmark)

    Blomdin, Robin; Murray, Andrew S.; Thomsen, Kristina Jørkov

    2012-01-01

    during deglaciation of the PIS, with an expected age range of 17 and 22 ka, and from recently deposited sediment. We measure small aliquots and single grain distributions using an IR50 SAR protocol with IRSL stimulation at 50 °C following a preheat at 250 °C (held for 60 s). Uncertainties are assigned......The timing of the ice margin retreat of the Late Glacial Patagonian Ice Sheet (PIS) in southern Patagonia has been the object of discussion for many years. In order to resolve questions about the complex response of the PIS to past climate change, any geological interpretation and data modelling...... environmental ODs between 30 and 130% and mean residual doses between ∼30 and 80 Gy. Minimum age models are used to identify the part of the dose population that is most likely to have been well-bleached and results from these models are compared. The models give ages that are consistent with each other...

  10. Alien invasions and the game of hide and seek in Patagonia.

    Directory of Open Access Journals (Sweden)

    Martin Lindegren

    Full Text Available The introduction, establishment and spread of alien species is a major threat to biodiversity and the provision of ecosystem services for human wellbeing. In order to reduce further loss of biodiversity and maintain productive and sustainable ecosystems, understanding the ecological mechanisms underlying species invasions and avoiding potentially harmful effects on native communities is urgently needed, but largely lacking. We here demonstrate, by means of hydroacoustics and advanced spatial modelling, how native fish species as a result of previous exposure to native predators may successfully respond to invasive novel predators through a complicated game of hide and seek, minimizing spatio-temporal overlap with predators, and potentially facilitating coexistence between native prey species (Galaxiids and introduced novel predators (Salmonids in a deep Andean lake, Patagonia.

  11. Eocene lantern fruits from Gondwanan Patagonia and the early origins of Solanaceae.

    Science.gov (United States)

    Wilf, Peter; Carvalho, Mónica R; Gandolfo, María A; Cúneo, N Rubén

    2017-01-06

    The nightshade family Solanaceae holds exceptional economic and cultural importance. The early diversification of Solanaceae is thought to have occurred in South America during its separation from Gondwana, but the family's sparse fossil record provides few insights. We report 52.2-million-year-old lantern fruits from terminal-Gondwanan Patagonia, featuring highly inflated, five-lobed calyces, as a newly identified species of the derived, diverse New World genus Physalis (e.g., groundcherries and tomatillos). The fossils are considerably older than corresponding molecular divergence dates and demonstrate an ancient history for the inflated calyx syndrome. The derived position of these early Eocene fossils shows that Solanaceae were well diversified long before final Gondwanan breakup. Copyright © 2017, American Association for the Advancement of Science.

  12. El cariotipo fundamental de Alstroemeria patagonica (Alstroemeriaceae The fundamental karyotype of Alstroemeria patagonia (Alstroemeriaceae

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    Carlos M Baeza

    2011-12-01

    Full Text Available Se describe el cariotipo de Alstroemeria patagonica Phil. a partir de material de Chile. Esta especie presenta un cariotipo 2n = 2x = 16, y una fórmula haploide de 1m + 2sm + 1sm-sat + 2st + 1st-sat + 1t. El cariotipo encontrado es muy asimétrico (AsK % = 76,0.The karyotype of Alstroemeria patagonia Phil. from Chile was described. The species had a karyotype 2n = 2x = 16, and the haploid formula was 1m + 2sm + 1sm-sat + 2st + 1st-sat + 1t. The reported karyotype was very asymmetric (AsK % = 76.0.

  13. Linked canopy, climate, and faunal change in the Cenozoic of Patagonia.

    Science.gov (United States)

    Dunn, Regan E; Strömberg, Caroline A E; Madden, Richard H; Kohn, Matthew J; Carlini, Alfredo A

    2015-01-16

    Vegetation structure is a key determinant of ecosystems and ecosystem function, but paleoecological techniques to quantify it are lacking. We present a method for reconstructing leaf area index (LAI) based on light-dependent morphology of leaf epidermal cells and phytoliths derived from them. Using this proxy, we reconstruct LAI for the Cenozoic (49 million to 11 million years ago) of middle-latitude Patagonia. Our record shows that dense forests opened up by the late Eocene; open forests and shrubland habitats then fluctuated, with a brief middle-Miocene regreening period. Furthermore, endemic herbivorous mammals show accelerated tooth crown height evolution during open, yet relatively grass-free, shrubland habitat intervals. Our Patagonian LAI record provides a high-resolution, sensitive tool with which to dissect terrestrial ecosystem response to changing Southern Ocean conditions during the Cenozoic. Copyright © 2015, American Association for the Advancement of Science.

  14. Ethical and Civic Education. Difficulties during the Curricular Reform in Argentine Patagonia

    Directory of Open Access Journals (Sweden)

    Isabelino Siede

    2015-04-01

    Full Text Available DOI: http://dx.doi.org/10.17227/01234870.41folios51.68 What type of ethical and civic education is effectively provided at school? This article analyzes the curricular prescriptions of Ethical and Citizenship Education in primary schools of the Argentine Patagonia, as well as its relations and contradictions with the school practices of moral education It inquires the process of definition of the area in the context of the Educational Reform in the 90s. Also, it pursuits to remake the way it was incorporated in the provincial curriculum design. Throughout focus groups and interviews to teachers from different public and private schools of three towns from de north of Santa Cruz, we analyze the descriptions and expectative of the teachers about their teaching practice in the moral area, as well as the possible causes of the differences and the contradictions between the policies of the curricular statement and educational proposals offered at school.

  15. Respiratory function in voluntary participating Patagonia sea lions in sternal recumbency

    Directory of Open Access Journals (Sweden)

    Andreas Fahlman

    2016-11-01

    Full Text Available We measured esophageal pressures (n=4, respiratory flow rates (n=5, and expired O2 and CO2 (n=4 in five adult Patagonia sea lions (Otaria flavescens, body mass range 94.3-286.0 kg during voluntary breaths while laying down. The data were used to estimate the dynamic specific lung compliance (sCL, cmH2O-1, the O2 consumption rate (VO2 and CO2 production rates (VCO2 during rest. Our results indicate that the resting tidal volume in Patagonia sea lions is approximately 47-73% of the estimated total lung capacity. The esophageal pressures indicated that expiration is passive during voluntary breaths. The average sCL of dolphins was 0.41±0.11 cmH2O−1, which is similar to those measured in anesthetized sea lions and awake cetaceans, and significantly higher as compared with humans (0.08 cmH2O−1. The average estimated and using breath-by-breath respirometry were 1.023 ± 0.327 L O2 min-1 (range: 0.695-1.514 L O2 min−1 and 0.777 ± 0.318 L CO2 min-1, (range: 0.510-1.235 L CO2 min-1, respectively, which is similar to previously published metabolic measurements from California and Steller sea lions using conventional flow-through respirometry. Our data provide end-tidal gas composition and provide novel data for respiratory physiology in pinnpeds, which may be important for clinical medicine and conservation efforts.

  16. Radiocarbon chronology of the last glacial maximum and its termination in northwestern Patagonia

    Science.gov (United States)

    Moreno, Patricio I.; Denton, George H.; Moreno, Hugo; Lowell, Thomas V.; Putnam, Aaron E.; Kaplan, Michael R.

    2015-08-01

    We examine the timing and magnitude of the last glacial maximum (LGM) and the last glacial termination (LGT) in northwestern Patagonia, situated in the middle latitudes of South America. Our data indicate that the main phase of the LGT began with abrupt warm pulses at 17,800 and 17,100 cal yrs BP, accompanied by rapid establishment of evergreen temperate rainforests and extensive deglaciation of the Andes within 1000 years. This response shows that South American middle-latitude temperatures had approached average interglacial values by 16,800 cal yrs BP. The temperature rise in northwestern Patagonia coincides with the beginning of major warming and glacier recession in the Southern Alps of New Zealand at southern mid-latitudes on the opposite side of the Pacific Ocean. From this correspondence, the warming that began at 17,800 cal yrs BP appears to have been widespread in middle latitudes of the Southern Hemisphere, accounting for at least 75% of the total temperature recovery from the LGM to the Holocene. Moreover, this warming pulse is coeval with the first half of the Heinrich Stadial 1 (HS1) in the North Atlantic region. HS1 featured a decline of North Atlantic meridional overturning circulation, a southward shift of the westerly wind belt in both hemispheres and of the Intertropical Convergence Zone, as well as a weakening of the Asian monsoon. Along with the initiating trigger, identifying the mechanisms whereby these opposing climate signals in the two polar hemispheres interacted -whether through an oceanic or an atmospheric bipolar seesaw, or both- lies at the heart of understanding the LGT.

  17. Luminescence dating of glacial advances at Lago Buenos Aires (∼46 °S), Patagonia

    Science.gov (United States)

    Smedley, R. K.; Glasser, N. F.; Duller, G. A. T.

    2016-02-01

    Understanding the timing of past glacial advances in Patagonia is of global climatic importance because of the insight this can provide into the influence on glacier behaviour of changes in temperature and precipitation related to the Southern Westerlies. In this paper we present new luminescence ages determined using single grains of K-feldspar from proglacial outwash sediments that were deposited by the Patagonian Ice Sheet around Lago Buenos Aires (∼46 °S), east of the contemporary Northern Patagonian Icefield. The new luminescence ages indicate that major outwash accumulations formed around ∼110 ± 20 ka to 140 ± 20 ka and that these correspond to the Moreno I and II moraine ridges, which were previously dated using cosmogenic isotope dating to 150 ± 30 ka. Luminescence dating at Lago Buenos Aires has also identified outwash sediments that were deposited during glacial advances ∼30.8 ± 5.7 ka and ∼34.0 ± 6.1 ka (MIS 3) that are not recorded in the moraine record. Younger outwash accumulations were then deposited between ∼14.7 ± 2.1 and 26.2 ± 1.6 ka which correspond to the Fenix I - V moraine ridges. The combined chronology suggests that glacial advances occurred ∼110 ± 20 ka to 150 ± 30 ka (MIS 6), ∼30.8 ± 5.7 ka to ∼34.0 ± 6.1 ka (MIS 3), and ∼14.7 ± 2.1 to 26.2 ± 1.6 ka (MIS 2) at Lago Buenos Aires. Overall luminescence dating using single grains of K-feldspar has excellent potential to contribute towards the ever-increasing geochronological dataset constraining the timings of glacial advances in Patagonia.

  18. Wind modulation of upwelling at the shelf-break front off Patagonia: Observational evidence

    Science.gov (United States)

    Carranza, M. M.; Gille, S. T.; Piola, A. R.; Charo, M.; Romero, S. I.

    2017-03-01

    The South-Atlantic Patagonian shelf is the largest chlorophyll-a (Chl-a) hot spot in Southern Ocean color images. While a persistent 1500 km long band of high Chl-a along the shelf-break front (SBF) is indicative of upwelling, the mechanisms that drive it are not entirely known. Along-front wind oscillations can enhance upwelling and provide a nutrient pumping mechanism at shelf-break fronts of western boundary currents. Here we assess wind-induced upwelling at the SBF off Patagonia from daily satellite Chl-a and winds, historical hydrographic observations, cross-shelf Chl-a fluorescence transects from two cruises, and in situ winds and water column structure from a mooring site. Satellite Chl-a composites segregated by along-front wind direction indicate that surface Chl-a is enhanced at the SBF with southerly winds and suppressed with northerly winds. Northerly winds also result in enhanced Chl-a further offshore (˜25-50 km). Synoptic transects as well as mean hydrographic sections segregated by along-front winds show isopycnals tilted upward for southerly winds. Spring observations from the mooring also suggest that southerly winds destratify the water column and northerly winds restratify, in agreement with Ekman transport interacting with the front. Moreover, changes in water column temperature lag along-front wind forcing by 2-4 days. Our results suggest that oscillations in along-front winds, on timescales typical of atmospheric storms (2-10 days), can significantly modulate the upwelling and Chl-a concentrations at the SBF off Patagonia, revealing the importance of wind-induced upwelling for shelf-slope exchange at shelf-break fronts of western boundary currents.

  19. Detection of Salmonella enterica in Magellanic penguins (Spheniscus magellanicus) of Chilean Patagonia: evidences of inter-species transmission.

    Science.gov (United States)

    Dougnac, C; Pardo, C; Meza, K; Arredondo, C; Blank, O; Abalos, P; Vidal, R; Fernandez, A; Fredes, F; Retamal, P

    2015-04-01

    Patagonia in southern South America is among the few world regions where direct human impact is still limited but progressively increasing, mainly represented by tourism, farming, fishing and mining activities. The sanitary condition of Patagonian wildlife is unknown, in spite of being critical for the assessment of anthropogenic effects there. The aim of this study was the characterization of Salmonella enterica strains isolated from wild colonies of Magellanic penguins (Spheniscus magellanicus) located in Magdalena Island and Otway Sound, in Chilean Patagonia. Eight isolates of Salmonella were found, belonging to Agona and Enteritidis serotypes, with an infection rate of 0·38%. Resistance to ampicillin, cefotaxime, ceftiofur and tetracycline antimicrobials were detected, and some of these strains showed genotypic similarity with Salmonella strains isolated from humans and gulls, suggesting inter-species transmission cycles and strengthening the role of penguins as sanitary sentinels in the Patagonian ecosystem.

  20. Random inbreeding, isonymy, and population isolates in Argentina.

    Science.gov (United States)

    Dipierri, José; Rodríguez-Larralde, Alvaro; Barrai, Italo; Camelo, Jorge López; Redomero, Esperanza Gutiérrez; Rodríguez, Concepción Alonso; Ramallo, Virginia; Bronberg, Rubén; Alfaro, Emma

    2014-07-01

    Population isolates are an important tool in identifying and mapping genes of Mendelian diseases and complex traits. The geographical identification of isolates represents a priority from a genetic and health care standpoint. The purpose of this study is to analyze the spatial distribution of consanguinity by random isonymy (F ST) in Argentina and its relationship with the isolates previously identified in the country. F ST was estimated from the surname distribution of 22.6 million electors registered for the year 2001 in the 24 provinces, 5 geographical regions, and 510 departments of the country. Statistically significant spatial clustering of F ST was determined using the SaTScan V5.1 software. F ST exhibited a marked regional and departamental variation, showing the highest values towards the North and West of Argentina. The clusters of high consanguinity by random isonymy followed the same distribution. Recognized Argentinean genetic isolates are mainly localized at the north of the country, in clusters of high inbreeding. Given the availability of listings of surnames in high-capacity storage devices for different countries, estimating F ST from them can provide information on inbreeding for all levels of administrative subdivisions, to be used as a demographic variable for the identification of isolates within the country for public health purposes.

  1. Relaciones polen-vegetación de algunos taxa de la estepa patagónica (Argentina Pollen-vegetation relationships of some taxa from the Patagonian steppe (Argentina

    Directory of Open Access Journals (Sweden)

    LIDIA S. BURRY

    2001-06-01

    Full Text Available La aplicación de un análisis de regresión lineal simple a datos de lluvia de polen y de vegetación, en una zona de la Patagonia (Provincia de Chubut, Argentina permitió relacionar cuantitativamente los porcentajes de lluvia polínica y de cobertura de la vegetación para los taxa Poaceae, Papilionoideae, tipo Senecio y Mulinum spinosum. Se obtuvo un buen ajuste de las rectas de regresión para cada uno de los taxa considerados, con coeficientes de correlación r de Pearson altos para M. spinosum (0,82 y tipo Senecio (0,81 y coeficientes algo menores en el caso de Poaceae (0,66 y Papilionoideae (0,61. Estas regresiones permitieron inferir la presencia o ausencia de polen regional y el valor predictivo de la presencia de polen en ausencia de la vegetación que lo produce. Al respecto, la lluvia de polen estudiada incluye el aporte regional (excepto Papilionoideae aun cuando M. spinosum tiene una baja contribución. Esta sobrerrepresentación es atribuible al transporte de larga distancia, a través de los vientos que provienen del oeste. Estas relaciones cuantitativas nos permitirán extrapolar cambios vegetacionales pasados en estos taxa a partir de espectros de polen fósil para el área de estudioThe use of simple linear regression to data of pollen rain and vegetation cover in Patagonia (Province of Chubut, Argentina allowed us to develop quantitative relationships between modern pollen rain perecentages and vegetation cover for the taxa Poaceae, Papilionoideae, Senecio type, and Mulinum spinosum. The analysis revealed a good fit of data to regression lines for all taxa, with high Pearson r coefficient values in the case of M. spinosum (0.82 and Senecio type (0.81, and somewhat lower values in the case of Poaceae (0.66 and Papilionoideae (0.61. These regressions allowed us to infer the presence or absence of regional pollen and predict the quantity of pollen in the absence of the vegetation producing it. In this regard, the studied pollen

  2. Exploring the Diversity and Antimicrobial Potential of Marine Actinobacteria from the Comau Fjord in Northern Patagonia, Chile

    OpenAIRE

    Agustina Undabarrena; Fabrizio Beltrametti; Fernanda Paz Claverías Ramos; Myriam González; Moore, Edward R. B.; Michael Seeger; Beatriz Patricia Cámara

    2016-01-01

    Bioprospecting natural products in marine bacteria from fjord environments are attractive due to their unique geographical features. Although, Actinobacteria are well known for producing a myriad of bioactive compounds, investigations regarding fjord-derived marine Actinobacteria are scarce. In this study, the diversity and biotechnological potential of Actinobacteria isolated from marine sediments within the Comau fjord, in Northern Chilean Patagonia, were assessed by culture-based approache...

  3. A Tenebrionid beetle’s dataset (Coleoptera, Tenebrionidae from Peninsula Valdés (Chubut, Argentina

    Directory of Open Access Journals (Sweden)

    German Cheli

    2013-12-01

    Full Text Available The Natural Protected Area Peninsula Valdés, located in Northeastern Patagonia, is one of the largest conservation units of arid lands in Argentina. Although this area has been in the UNESCO World Heritage List since 1999, it has been continually exposed to sheep grazing and cattle farming for more than a century which have had a negative impact on the local environment. Our aim is to describe the first dataset of tenebrionid beetle species living in Peninsula Valdés and their relationship to sheep grazing. The dataset contains 118 records on 11 species and 198 adult individuals collected. Beetles were collected using pitfall traps in the two major environmental units of Peninsula Valdés, taking into account grazing intensities over a three year time frame from 2005–2007. The Data quality was enhanced following the best practices suggested in the literature during the digitalization and geo-referencing processes. Moreover, identification of specimens and current accurate spelling of scientific names were reviewed. Finally, post-validation processes using DarwinTest software were applied. Specimens have been deposited at Entomological Collection of the Centro Nacional Patagónico (CENPAT-CONICET. The dataset is part of the database of this collection and has been published on the internet through GBIF Integrated Publishing Toolkit (IPT (http://data.gbif.org/datasets/resource/14669/. Furthermore, it is the first dataset for tenebrionid beetles of arid Patagonia available in GBIF database, and it is the first one based on a previously designed and standardized sampling to assess the interaction between these beetles and grazing in the area. The main purposes of this dataset are to ensure accessibility to data associated with Tenebrionidae specimens from Peninsula Valdés (Chubut, Argentina, also to contribute to GBIF with primary data about Patagonian tenebrionids and finally, to promote the Entomological Collection of Centro Nacional Patag

  4. The Usefulness of Edible and Medicinal Fabaceae in Argentine and Chilean Patagonia: Environmental Availability and Other Sources of Supply

    Directory of Open Access Journals (Sweden)

    Soledad Molares

    2012-01-01

    Full Text Available Fabaceae is of great ethnobotanical importance in indigenous and urban communities throughout the world. This work presents a revision of the use of Fabaceae as a food and/or medicinal resource in Argentine-Chilean Patagonia. It is based on a bibliographical analysis of 27 ethnobotanical sources and catalogues of regional flora. Approximately 234 wild species grow in Patagonia, mainly (60% in arid environments, whilst the remainder belong to Sub-Antarctic forest. It was found that 12.8% (30 species, mainly woody, conspicuous plants, are collected for food or medicines. Most of the species used grow in arid environments. Cultivation and purchase/barter enrich the Fabaceae offer, bringing it up to a total of 63 species. The richness of native and exotic species, and the existence of multiple strategies for obtaining these plants, indicates hybridization of knowledge and practices. Only 22% of the total species used are mentioned in bothcontexts of food and medicine, reflecting low-use complementation. This study suggests a significant ecological appearance and a high level of availability in shops and exchange networks in Patagonia, highlighting the need to consider the full set of environmental and socioeconomic factors in research related to the use and cultural importance of plants in regional contexts.

  5. Mida õpetab Argentina finantskriis? / Karsten Staehr

    Index Scriptorium Estoniae

    Staehr, Karsten, 1962-

    2002-01-01

    Norra majandusanalüütik kirjeldab Argentina majanduspoliitikat, analüüsib tehtud vigu ning hoiatab avatud majandusega Eestit võimalike tulevaste välisshokkide eest. Diagramm: SKP kasv ja üleüldine riigieelarve tasakaal 1991-2001 Argentinas

  6. The Stenopodainae (Hemiptera, Heteroptera) of Argentina

    Science.gov (United States)

    Diez, Fernando; Coscarón, María del Carmen

    2014-01-01

    Abstract In Argentina, 10 genera and 33 species of Stenopodainae (Hemiptera: Reduviidae) have been recorded. Diagnoses of the genera, subgenera and species are given, and an illustrated key to genera is provided. Six species are new records for Argentina and an additional seven species represent new records for provinces. PMID:25493054

  7. Development and application of a low-cost, portable DOAS system for stratospheric composition monitoring over the Argentinean Patagonia and Antarctic stations.

    Science.gov (United States)

    Raponi, Marcelo; Jiménez, Rodrigo; Ristori, Pablo; Wolfram, Elian; Tocho, Jorge; Quel, Eduardo

    2010-05-01

    A significant fraction of the Argentinean population is seasonally exposed to elevated UV radiation, particularly during severe stratospheric ozone destruction episodes in Antarctica. In order to provide early alert, global monitoring and to improve our understanding of these phenomena, various Argentinean and international organizations maintain stratospheric composition remote sensing sites from the southern tip of Argentina (Patagonia) to Antarctica. The understating of the ozone destruction dynamics will be significantly improved if more sites were available. For instance, the Laser and Applications Research Center, CEILAP (CITEFA-CONICET, Argentina) carries out systematic measurements of stratospheric ozone and tropospheric water vapor profiles at Rio Gallego (51° 36' S, 69° 19' W, 15 m asl) by means of LIDAR systems. Besides the active systems, the site possesses different passive instruments (GUV-541, UV-B and UV-A radiometers, SAOZ spectrometer, CIMEL sunphotometer) all of them working in synergy. The goal of this work is to present the design and development of a new compact atmospheric remote sensing system, able to determine the vertical column concentration in column (VCD) of multiple trace gases. We have developed a low-cost, portable passive DOAS system, ERO-DOAS, wich circumvents the cost limitations associated with new fixed monitoring sites. It is composed of commercial spectrophotometer (HR4000, Ocean Optics), a 400-μm core, 6-m long optic fiber, and a home-made automatic external shutter. We have developed a LabVIEW® based software for spectrometer/shutter control and data acquisition, and a MATLAB® based software for spectral data reduction. In the work we highlight the main characteristics of the system's components and we describe the visual interface implemented to controls the operation of the whole system, and the calculation algorithms to process the measured zenithal spectra, postulating the strategies implemented to solve the

  8. Estado del conocimiento de humedales del norte patagónico (Argentina: aspectos relevantes e importancia para la conservación de la biodiversidad regional State of the knowledge of north Patagonian wetlands (Argentina: major aspects and importance for regional biodiversity conservation

    Directory of Open Access Journals (Sweden)

    MARÍA G PEROTTI

    2005-12-01

    Full Text Available Las áreas de humedal ocupan casi el 5 % del territorio de la Patagonia argentina. En la zona extrandina y el desierto patagónico estos ecosistemas son esenciales para sostener numerosas especies de fauna y flora silvestre. Además, los humedales del norte patagónico permiten el desarrollo de comunidades acuáticas complejas y constituyen el hábitat crítico de grupos de organismos como los peces y los anfibios incluidos en listados de conservación prioritaria. Estos ecosistemas tienen un funcionamiento complejo que depende estrechamente de las fluctuaciones de las variables meteorológicas y son por lo tanto muy sensibles a los efectos del cambio climático. En la actualidad el uso de la tierra, la introducción de especies y la interacción de estos aspectos con el cambio climático constituyen las variables de mayor impacto sobre estos ambientes patagónicos. En este trabajo se presenta información geográfica, geomorfológica y climática de un número de humedales del norte de la Patagonia argentina. Por otra parte, se sintetiza información sobre la flora y la distribución de peces y anfibios con el propósito de enfatizar la importancia de estos ambientes en el mantenimiento de la biodiversidad regional. Por último, se señalan los procesos que actualmente afectan a estos sistemas poniendo en evidencia la necesidad de obtención de conocimientos básicos para el diseño de planes de manejo y conservación de sus comunidades biológicasAlmost 5 % of the lansdscape of Patagonia is occupied by wetlands. In the extra-andean region and the patagonian desert, wetlands are essential for sustaining biodiversity and wildlife. Besides, North patagonian wetlands present complex aquatic communities and provide habitat for threatened species of fishes and amphibians. These ecosystems have complex dynamics mostly driven by climatic fluctuations which make them vulnerable to the effect of climate change. Nowadays, the main impact on patagonian

  9. ¿El contexto geográfico importa en la mortalidad por diabetes mellitus? Tendencias espacio-temporales en Argentina, 1990-2012

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    Carlos M. Leveau

    Full Text Available Resumen: El objetivo de esta investigación fue identificar conglomerados espacio-temporales de alta y baja mortalidad por diabetes mellitus durante el período 1990-2012 en Argentina. Se realizó un estudio ecológico retrospectivo espacio-temporal. Se consideró la población mayor de 34 años residente en Argentina, según sexo, durante el período 1990-2012. Las unidades espaciales de análisis estuvieron conformadas por departamentos más la Ciudad Autónoma de Buenos Aires. Se empleó la técnica de exploración espacio-temporal para la detección de conglomerados de alta y baja mortalidad. Se encontraron áreas de elevada mortalidad por diabetes mellitus en el centro-oeste del país, y zonas de baja mortalidad en la región costera de la provincia de Buenos Aires y Patagonia. Los conglomerados de alta mortalidad ocuparon un período comprendido entre 1995 y 2008; los de baja mortalidad se desplazaron hacia los años 2002-2012. El descenso reciente en la mortalidad por diabetes mellitus no fue geográficamente homogéneo, con una disminución marcada en el este de la Provincia de Buenos Aires y la Ciudad Autónoma de Buenos Aires.

  10. West Nile Virus

    Science.gov (United States)

    West Nile virus (WNV) is an infectious disease that first appeared in the United States in 1999. Infected mosquitoes ... and usually go away on their own. If West Nile virus enters the brain, however, it can be life- ...

  11. Tortugas marinas en aguas argentinas

    OpenAIRE

    Gonzalez Carman, V.; Mianzan, H.; Bruno, I.; Prosdocimi, L.; Albareda, D.; Campagna, C.

    2012-01-01

    Con la ayuda de los sensores remotos y los sistemas de posicionamiento geográfico, los científicos están descubriendo varias facetas sobre las vida de las tortugas marinas. Se describe el método para realizar el siguimiento satelital, sus migraciones, y se dan las características de las especies de tortugas marinas encontradas en aguas costeras de la Argentina. Este trabajo de divulgación científica hace hincapié en la importancia de su conservación, según la Unión Internacional para la Conse...

  12. Argentina. Libertad de Prensa recortada

    Directory of Open Access Journals (Sweden)

    Alexis Socco

    2007-10-01

    Full Text Available A decir del autor y la opinión de la SIP la libertad de prensa y la empresa en Argentina están bastante limitadas. Señala la trayectoria vivida por la libertad de prensa en los diferentes gobiernos. Acusa de que no existe Legislación para obtener información de los distintos poderes del Estado no hay ley para la publicidad etc. Comenta además sobre el caso de Gustavo Sierra y el Clarín.

  13. Bioceres: AG Biotechnology from Argentina

    Directory of Open Access Journals (Sweden)

    Roberto Feeney

    2016-04-01

    Full Text Available In this case we present a business decision-making situation in which the CEO of an Argentine Ag Biotech company, Bioceres, has to decide the best way to commercialize a new drought-tolerant transgenic technology. The company was founded by twenty three farmers, who shared a common dream that Argentina could become a benchmark in the development of Ag biotechnology. The case has strategic and financial implications, as well as decision-making situation involving a joint venture with an American biotechnology company. It also introduces to discussion the business models of Ag biotechnology companies in developing countries.

  14. Invasion status of the common carp Cyprinus carpio in inland waters of Argentina.

    Science.gov (United States)

    Maiztegui, T; Baigún, C R M; Garcia de Souza, J R; Minotti, P; Colautti, D C

    2016-07-01

    This study documents the presence of Cyprinus carpio in 119 natural environments and 49 artificial habitats in Argentina, showing an exponential increment of invaded locations over time since it was introduced in the nineteenth century. Geographic expansion patterns revealed that since its initial introduction, species records demonstrate an increment in the central portion of the country only after 1970 and subsequent expansion after 1990 to the north, west and south. Using an environmental similarity index it was determined that more than half the country offers good conditions for C. carpio establishment. Environmental factors and anthropogenic impacts are relevant drivers that can account for the current and future distribution of C. carpio in Argentina. © 2016 The Fisheries Society of the British Isles.

  15. What's West Nile Virus?

    Science.gov (United States)

    ... OK for Kids? Your Teeth Heart Murmurs What's West Nile Virus? KidsHealth > For Kids > What's West Nile Virus? Print A A A en español ¿Qué es ... Virus del Nilo Occidental? What exactly is the West Nile virus? And why is everyone talking about mosquitoes ? Even ...

  16. Uncoupled vs. coupled thrust belt-foreland deformation: a model for northern Patagonia inferred from U-Th/He and apatite fission track dating

    Science.gov (United States)

    Savignano, Elisa; Mazzoli, Stefano; Zattin, Massimiliano; Gautheron, Cécile; Franchini, Marta

    2017-04-01

    The study of the Cretaceous - Cenozoic evolution of the Patagonian Andes represents a great opportunity to investigate the effects of coupling between deep lithospheric processes and near-surface deformation. Low-temperature thermochronological systems are ideally suited for detecting events involving rocks in the uppermost part of the crust because they record time and rates of cooling related to exhumation of the top few kilometers of the crust. The Patagonia region, although characterized by a general continuity of the Andean orogen along its strike, shows an appreciable internal tectonic segmentation (marked by a variable position of the magmatic arc and of the deformation front in the retroarc area) at various latitudes. This complex structural architecture has been interpreted as the result of different processes acting since the Late Cretaceous. The present-day configuration of the southern Andes is interpreted to have been controlled by alternating stages of flat- and steep-slab subduction, which produced shortening and upper plate extension episodes,, respectively. Furthermore, the deformation in this whole retroarc sector varied not only in time (i.e. with major 'cycles' of mountain building and orogenic collapse), but also in space, due to the variable transmission of horizontal compressive stress away from the orogen, that produced an irregular unroofing pattern. In this study, we have integrated field structural observations with new apatite (U-Th)/He data (AHe) and apatite fission-track (AFT) ages in the north Patagonia region (at latitudes between 40° and 44°S) in order to analyse and compare the exhumation patterns from the frontal part of the orogen and from the adjacent foreland sector, as well as to gain new insights into the timing and modes of coupling vs. uncoupling of the deformation between the northern Patagonian fold and thrust belt and its foreland. The obtained data indicate a markedly different unroofing pattern between the 'broken

  17. Filogenia y biogeografía de los peces teleósteos (Actinopterygii, Teleostei) de la Formación Cañadón Calcáreo (Jurásico; Provincia del Chubut, Argentina)

    OpenAIRE

    Sferco, Marta Emilia

    2013-01-01

    En esta tesis se aborda el estudio sistemático y paleobiogeográfico de los teleósteos del Jurásico Tardío de la Fm. Cañadón Calcáreo de Patagonia, Argentina. A fin de poner a prueba el estatus taxonómico de las dos especies nominales †‘Tharrhias’ feruglioi Bordas, 1942 y †Luisiella inexcutata Bocchino, 1967, descriptas previamente para la formación, se llevaron a cabo un estudio anatómico comparativo detallado y análisis merísticos y morfométricos lineales de los especímenes de teleósteos dis...

  18. Sistema de salud de Argentina The health system of Argentina

    Directory of Open Access Journals (Sweden)

    Mariana Belló

    2011-01-01

    Full Text Available En este artículo se describe el sistema de salud de Argentina, que está compuesto por tres sectores: público, de seguridad social y privado. El sector público está integrado por los ministerios nacional y provincial, y la red de hospitales y centros de salud públicos que prestan atención gratuita a toda persona que lo demande, fundamentalmente a personas sin seguridad social y sin capacidad de pago. Se financia con recursos fiscales y recibe pagos ocasionales de parte del sistema de seguridad social cuando atiende a sus afiliados. El sector del seguro social obligatorio está organizado en torno a las Obras Sociales (OS, que aseguran y prestan servicios a los trabajadores y sus familias. La mayoría de las OS operan a través de contratos con prestadores privados y se financian con contribuciones de los trabajadores y patronales. El sector privado está conformado por profesionales de la salud y establecimientos que atienden a demandantes individuales, a los beneficiarios de las OS y de los seguros privados. Este sector también incluye entidades de seguro voluntario llamadas Empresas de Medicina Prepaga que se financian sobre todo con primas que pagan las familias y/o las empresas. En este trabajo también se describen las innovaciones recientes en el sistema de salud, incluyendo el Programa Remediar.This paper describes the health system of Argentina.This system has three sectors: public, social security and private.The public sector includes the national and provincial ministries as well as the network of public hospitals and primary health care units which provide care to the poor and uninsured population. This sector is financed with taxes and payments made by social security beneficiaries that use public health care facilities. The social security sector or Obras Sociales (OS covers all workers of the formal economy and their families. Most OS operate through contracts with private providers and are financed with payroll

  19. Melt Patterns and Dynamics in Alaska and Patagonia Derived from Passive Microwave Brightness Temperatures

    Directory of Open Access Journals (Sweden)

    Kathryn Semmens

    2014-01-01

    Full Text Available Glaciers and icefields are critical components of Earth’s cryosphere to study and monitor for understanding the effects of a changing climate. To provide a regional perspective of glacier melt dynamics for the past several decades, brightness temperatures (Tb from the passive microwave sensor Special Sensor Microwave Imager (SSM/I were used to characterize melt regime patterns over large glacierized areas in Alaska and Patagonia. The distinctness of the melt signal at 37V-GHz and the ability to acquire daily data regardless of clouds or darkness make the dataset ideal for studying melt dynamics in both hemispheres. A 24-year (1988–2011 time series of annual Tb histograms was constructed to (1 characterize and assess temporal and spatial trends in melt patterns, (2 determine years of anomalous Tb distribution, and (3 investigate potential contributing factors. Distance from coast and temperature were key factors influencing melt. Years of high percentage of positive Tb anomalies were associated with relatively higher stream discharge (e.g., Copper and Mendenhall Rivers, Alaska, USA and Rio Baker, Chile. The characterization of melt over broad spatial domains and a multi-decadal time period offers a more comprehensive picture of the changing cryosphere and provides a baseline from which to assess future change.

  20. Latest Pleistocene and Holocene glacial events in the Colonia valley, Northern Patagonia Icefield, southern Chile

    Science.gov (United States)

    Nimick, David A.; Mcgrath, Daniel; Mahan, Shannon; Friesen, Beverly A.; Leidich, Jonathan

    2016-01-01

    The Northern Patagonia Icefield (NPI) is the primary glaciated terrain worldwide at its latitude (46.5–47.5°S), and constraining its glacial history provides unique information for reconstructing Southern Hemisphere paleoclimate. The Colonia Glacier is the largest outlet glacier draining the eastern NPI. Ages were determined using dendrochronology, lichenometry, radiocarbon, cosmogenic 10Be and optically stimulated luminescence. Dated moraines in the Colonia valley defined advances at 13.2 ± 0.95, 11.0 ± 0.47 and 4.96 ± 0.21 ka, with the last being the first constraint on the onset of Neoglaciation for the eastern NPI from a directly dated landform. Dating in the tributary Cachet valley, which contains an ice-dammed lake during periods of Colonia Glacier expansion, defined an advance at ca. 2.95 ± 0.21 ka, periods of advancement at 810 ± 49 cal a BP and 245 ± 13 cal a BP, and retreat during the intervening periods. Recent Colonia Glacier thinning, which began in the late 1800s, opened a lower-elevation outlet channel for Lago Cachet Dos in ca. 1960. Our data provide the most comprehensive set of Latest Pleistocene and Holocene ages for a single NPI outlet glacier and expand previously developed NPI glacial chronologies.

  1. Discovery of a short-necked sauropod dinosaur from the Late Jurassic period of Patagonia.

    Science.gov (United States)

    Rauhut, Oliver W M; Remes, Kristian; Fechner, Regina; Cladera, Gerardo; Puerta, Pablo

    2005-06-02

    Sauropod dinosaurs are one of the most conspicuous groups of Mesozoic terrestrial vertebrates. They show general trends towards an overall increase in size and elongation of the neck, by means of considerable elongation of the length of individual vertebrae and a cervical vertebra count that, in some cases, increases to 19 (ref. 1). The long neck is a particular hallmark of sauropod dinosaurs and is usually regarded as a key feeding adaptation. Here we describe a new dicraeosaurid sauropod, from the latest Jurassic period of Patagonia, that has a particularly short neck. With a neck that is about 40% shorter than in other known dicraeosaurs, this taxon demonstrates a trend opposite to that seen in most sauropods and indicates that the ecology of dicraeosaurids might have differed considerably from that of other sauropods. The new taxon indicates that there was a rapid radiation and dispersal of dicraeosaurids in the Late Jurassic of the Southern Hemisphere, after the separation of Gondwana from the northern continents by the late Middle Jurassic.

  2. Malvinas-slope water intrusions on the northern Patagonia continental shelf

    Directory of Open Access Journals (Sweden)

    A. R. Piola

    2010-03-01

    Full Text Available The Patagonia continental shelf located off southeastern South America is bounded offshore by the Malvinas Current, which extends northward from northern Drake Passage (~55° S to nearly 38° S. The transition between relatively warm-fresh shelf waters and Subantarctic Waters from the western boundary current is characterized by a thermohaline front extending nearly 2500 km. We use satellite derived sea surface temperature, and chlorophyll-a data combined with hydrographic and surface drifter data to document the intrusions of slope waters onto the continental shelf near 41° S. These intrusions create vertically coherent localized negative temperature and positive salinity anomalies extending onshore about 150 km from the shelf break. The region is associated with a center of action of the first mode of non-seasonal sea surface temperature variability and also relatively high chlorophyll-a variability, suggesting that the intrusions are important in promoting the local development of phytoplankton. The generation of slope water penetrations at this location may be triggered by the inshore excursion of the 100 m isobath, which appears to steer the Malvinas Current waters over the outer shelf.

  3. Spatial dynamics of Fabiana imbricata shrublands in northwestern Patagonia in relation to natural fires

    Directory of Open Access Journals (Sweden)

    L. Ghermandi

    2010-05-01

    Full Text Available Fire is a critical disturbance in the structuring and functioning of most Mediterranean ecosystems. In northwestern Patagonia, vegetation patterns are strongly influenced by fire and environmental heterogeneity. Dendroecology, together with satellite imagery and GIS, have been demonstrated to be useful tools in studies that relate to fire effects with patches, patterns and species dynamics at landscape scale. Such studies can be approached from landscape ecology, which has evolved in the last years supported by the development of remote sensing and GIS technologies. This study evaluates the spatial dynamic of F. imbricata in response to fire using remote sensing, GIS and dendrochronology techniques, at landscape scale. Two sites were evaluated and one of them was affected by fire in the year 1999. The digital processing images (using the NBR spectral index and the dendroecological analysis verified this. A fire, occurring in 1978, was also detected by the analysis of F. imbricata growth rings. The relation between F. imbricata shrubland dynamics and spatial configuration with fire, land topography and hydrography was established in the study area.

  4. Spatial dynamics of Fabiana imbricata shrublands in northwestern Patagonia in relation to natural fires

    Science.gov (United States)

    Oddi, F. J.; Dudinszky, N.; Ghermandi, L.

    2010-05-01

    Fire is a critical disturbance in the structuring and functioning of most Mediterranean ecosystems. In northwestern Patagonia, vegetation patterns are strongly influenced by fire and environmental heterogeneity. Dendroecology, together with satellite imagery and GIS, have been demonstrated to be useful tools in studies that relate to fire effects with patches, patterns and species dynamics at landscape scale. Such studies can be approached from landscape ecology, which has evolved in the last years supported by the development of remote sensing and GIS technologies. This study evaluates the spatial dynamic of F. imbricata in response to fire using remote sensing, GIS and dendrochronology techniques, at landscape scale. Two sites were evaluated and one of them was affected by fire in the year 1999. The digital processing images (using the NBR spectral index) and the dendroecological analysis verified this. A fire, occurring in 1978, was also detected by the analysis of F. imbricata growth rings. The relation between F. imbricata shrubland dynamics and spatial configuration with fire, land topography and hydrography was established in the study area.

  5. A systematic overview of Descolea (Agaricales) in the Nothofagaceae forests of Patagonia.

    Science.gov (United States)

    Kuhar, Francisco; Smith, Matthew E; Mujic, Alija; Truong, Camille; Nouhra, Eduardo

    2017-10-01

    The descolea clade includes species of ectomycorrhizal basidiomycetes in the genera Descolea, Setchelliogaster, Descomyces, and Timgrovea that are known primarily from the Southern Hemisphere. Taxa in this group produce basidiomes that range in morphology from typical epigeous mushrooms (Descolea) and secotioid taxa (Setchelliogaster) to fully gasteroid species (Descomyces and Timgrovea). High intraspecific morphological variation has been reported in several species within this clade, suggesting that careful morphological and molecular studies are needed to refine species concepts. Molecular analyses of fresh Patagonian collections in conjunction with taxonomic studies have confirmed high variability in key morphological features, including overall sporocarp form, spore shape and dimensions, universal veil remnants, and cuticle configuration. Based on our synthesis, we emend the genus Descolea to include sequestrate species. We describe the new sequestrate taxon Descolea inferna sp. nov. from Nothofagaceae forests in Patagonia and we propose Cortinarius squamatus as a synonym of our new combination Descolea brunnea. We also formalize the identity of Descolea pallida as a synonym of Descolea antarctica and provide new specimens of Cortinarius archeuretus, a species that has not been encountered since the original discovery during the expeditions of Roland Thaxter in 1905-1906. Here we re-describe and transfer this species to Descolea as D. archeureta. We also discuss diagnostic features that can be used to delimitate the four known South American taxa in the descolea clade. Copyright © 2017 British Mycological Society. All rights reserved.

  6. Late Pleistocene ecological, environmental and climatic reconstruction based on megafauna stable isotopes from northwestern Chilean Patagonia

    Science.gov (United States)

    González-Guarda, Erwin; Domingo, Laura; Tornero, Carlos; Pino, Mario; Hernández Fernández, Manuel; Sevilla, Paloma; Villavicencio, Natalia; Agustí, Jordi

    2017-08-01

    Stable isotope analyses have been performed on the bioapatite (δ13C; δ18O) and collagen (δ13C; δ15N) of four late Pleistocene South American megafaunal taxa (Notiomastodon platensis, Equus andium, cf. Hemiauchenia paradoxa and Xenarthra indet.) to evaluate paleoclimatic and paleoenvironmental conditions as well as paleoecological features of this time period. The analyzed megafauna was found at several locations in the northwestern Chilean Patagonia (38°-42°S, 74°-71°W). The bioapatite δ13C values indicated the presence of C3 vegetation ranging from forestal to woodland areas. The collagen δ15N values pointed to temperate and humid ecosystems, and to the consumption of shrubs, trees, grasses and sedges. Mean annual temperatures estimated from bioapatite δ18OPO4 values show a similarity to modern temperatures and suggested that the megafauna under study may have lived during warm stages (interstadials) of the late Pleistocene. When comparing our results with those obtained from other South American regions, we find that the diet of this particular Chilean megafauna appears to have been more influenced by resource availability than by the potential dietary range of the taxa.

  7. The sea anemone Bunodactis octoradiata (Anthozoa: Actiniaria from southern Patagonia: morphological study and new records

    Directory of Open Access Journals (Sweden)

    Agustín Garese

    2014-10-01

    Full Text Available Bunodactis Verril, 1899 comprises at present 19 nominal species of sea anemones. The validity of the genus is under discussion. The description of the species, Bunodactis octoradiata Carlgren, 1899, is insufficient for reliable identification, and although subsequent works have provided additional information on the species, its description still needs to be complemented. Herein we describe B. octoradiata based on histological sections of the internal anatomy, and give a complete and detailed description of the external anatomy. The cnidom is composed of spirocysts, basitrichs and microbasic p-mastigophores; their distribution in the organism, sizes and relative abundances are provided. The presence of zooxanthellae is reported for the first time. Bunodactis octoradiata is distributed in groups that vary from 5.6 to 45 ind./m² in the field. Additionally, our data extends the distribution of the species along the coast of southern Patagonia (47°44'36"-49°15'13"S and 65°50'26"-67°39'45"W.

  8. A Middle Jurassic abelisaurid from Patagonia and the early diversification of theropod dinosaurs.

    Science.gov (United States)

    Pol, Diego; Rauhut, Oliver W M

    2012-08-22

    Abelisaurids are a clade of large, bizarre predatory dinosaurs, most notable for their high, short skulls and extremely reduced forelimbs. They were common in Gondwana during the Cretaceous, but exceedingly rare in the Northern Hemisphere. The oldest definitive abelisaurids so far come from the late Early Cretaceous of South America and Africa, and the early evolutionary history of the clade is still poorly known. Here, we report a new abelisaurid from the Middle Jurassic of Patagonia, Eoabelisaurus mefi gen. et sp. nov., which predates the so far oldest known secure member of this lineage by more than 40 Myr. The almost complete skeleton reveals the earliest evolutionary stages of the distinctive features of abelisaurids, such as the modification of the forelimb, which started with a reduction of the distal elements. The find underlines the explosive radiation of theropod dinosaurs in the Middle Jurassic and indicates an unexpected diversity of ceratosaurs at that time. The apparent endemism of abelisauroids to southern Gondwana during Pangean times might be due to the presence of a large, central Gondwanan desert. This indicates that, apart from continent-scale geography, aspects such as regional geography and climate are important to reconstruct the biogeographical history of Mesozoic vertebrates.

  9. New evidence of the sabertooth cat Smilodon (Carnivora: Machairodontinae in the late Pleistocene of southern Chilean Patagonia Nueva evidencia del gato dientes de sable Smilodon (Carnivora: Machairodontinae en el Pleistoceno tardío de Patagonia meridional chilena

    Directory of Open Access Journals (Sweden)

    ALFREDO PRIETO

    2010-06-01

    Full Text Available Southern Patagonia is rich in late Pleistocene mammals, especially herbivores such as Camelids, Equids and Xenarthrans. Carnivores, on the other hand, are not commonly found in the paleontological record. One genus, Smilodon, is of particular interest because its presence in the region has not been demonstrated. In this paper, we present new fossil dental evidence that supports the presence of Smilodon populator (Lund in the region. This evidence corresponds to the most southern record of the genus in the world, and the final step in the colonization of South America after the Great American Biotic Interchange. An AMS radiocarbon date on teeth indicates that the remains from Southern Chilean Patagonia are the most recent record for the genus in South America.Surpatagonia es particularmente rica en mamíferos finiplesitocenos, particularmente camélidos, équidos y xenartros. Los carnívoros, por su parte, se encuentran representados en menor número en el registro paleontológico. Dentro de estos, el género Smilodon, es de particular interés debido a que su presencia en la región no ha sido convincentemente demostrada. En este trabajo presentamos evidencia dental que permite confirmar la presencia de Smilodon populator (Lund en la región. Esta evidencia corresponde al registro más sureño de este taxón y al paso final en la colonización de América del Sur después del Gran Intercambio Biótico Americano. Un fechado radiocarbónico directo AMS indica que los restos de Patagonia del Sur corresponden a los registros más tardíos para este género en el subcontinente.

  10. Argentina: entre o Mercosul e a Alca

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    Raúl Bernal-Meza

    2001-12-01

    Full Text Available Este artigo procura mostrar que a Argentina não está numa encruzilhada na sua política externa, tendo que escolher entre Mercosul ou Alca. Ao contrário, a Argentina vê o Mercosul como um caminho que leva à Alca, afirmando uma posição que se tornou possível depois da confluência de outros fatores, como a posição brasileira frente a Alca e o modelo de integração regional proposta para o Mercosul.This article seeks to show that Argentina is not in crossroads in your foreign policy, having to choose between Mercosur and FTAA. In contrast, Argentina sees Mercosur as a way that leads to FTAA, affirming a position that become possible after a confluence of others factors, as the Brazilian position front Alca and the model of regional integration proposal for Mercosur.

  11. Range expansion of Oligoryzomys longicaudatus (Rodentia, Sigmodontinae in Patagonian Chile, and first record of Hantavirus in the region Ampliación del rango de distribución de Oligoryzomys longicaudatus (Rodentia, Sigmodontinae en la Patagonia de Chile y primer registro de Hantavirus en la región

    Directory of Open Access Journals (Sweden)

    SEBASTIÁN BELMAR-LUCERO

    2009-06-01

    Full Text Available At present, 20 species of Oligoryzomys (Rodentia, Sigmodontinae are recognized in the Neotropical region, most of them distinguished by their karyotypes, which fluctuates between 46-70 chromosomes. Two species are currently recognized in Chile, Oligoryzomys longicaudatus (Bennet, 1832; "colilargo" or the long-tailed pygmy rice rat; 2n = 56, which ranges from 27° to approximately 51° S, and O. magellanicus (Bennet, 1836; Magellanic pygmy rice rat; 2n = 54, south of 51° S in the Patagonian region of Chile and Argentina. As part of an ongoing research on the southern Patagonia of Chile, we report the results of small mammal samplings in six localities. We karyotyped 28 specimens and we also sequenced the hypervariable mtDNA region I in 22 individuals, aligning these sequences with an under development phylogeny of O. longicaudatus. We also evaluated the serology and viral charge in all captured specimens to detect the presence of antibodies to Andes virus (ANDV through Strip Immunoblot Assay (SIA, and of viral genome by RT-PCR. The results consistently showed that the karyotype of southern Patagonia specimens was 2n = 56, equal to that of O. longicaudatus, and that individuals from this area do not differentiate phylogenetically from those of the northern range of distribution. In addition, the serology showed the presence of antibodies IgG anti-ANDV and of viral genome in heart, kidney, spleen, and lungs of a single specimen of Oligoryzomys from the locality of Fuerte Bulnes in the Magallanes region. We conclude that all specimens trapped south of 51° S correspond to Oligoryzomys longicaudatus, thus expanding the distribution of this specie! from 51° to at least 55° S. The results also extended the disiribution of the Andes strain of Hantavirus to southernmost Patagonia.Actualmente se reconocen 20 especies de Oligoryzomys (Rodentia, Sigmodontinae en la región Neotropical, la mayoría de ellas distinguidas por sus cariotipos, los que fluct

  12. National Labor Administration and Democracy in Argentina

    Science.gov (United States)

    1987-08-01

    Thompson, eds., Sindicalismo y Reimenes Militares en Argentina Y Chile. Amsterdam: CEDLA, 1982. 4 2 p.C. Schmitter, "Organized Interests and Democratic... Mexicanos Unidos, 1964; R. Alexander, La-or Relations in Argentina, Brazil, and Chile. New York: McGraw-Hill, 1962; S M Dais and L.W. Goodman, eds. Workers...Carri, Sindicatos y Poder en la A-gentina. Buenos Aires: Editorial Sudestaba, 1967; R. Rotundaro, Realidad y Cambio en el Sindicalismo . Buenos Aires

  13. Che cosa impariamo dalla crisi argentina

    OpenAIRE

    Bianchi Patrizio

    2002-01-01

    This article explores the industrial roots of the present Argentina's crisis. Since the mid of 19th century, Argentina developed a model of social modernization without industrialization, based on export of primary commodity to Western developed countries. This model was exhausted during the 1930s; crisis, because of the ring of protectionism in the Western countries and replaced by an import-substitution approach, which promoted a wide range of small sub-optimal plants. In the mid-1970s, the...

  14. Occurrence of Meloidogyne spp. in Argentina.

    Science.gov (United States)

    Doucet, M E; Pinochet, J

    1992-12-01

    A record of 84 plant species in 32 families that are hosts to the root-knot nematode species found in Argentina is presented. The genus Meloidogyne appears to be widely distributed in the country, with Meloidogyne incognita and M. javanica the most frequently detected species. Other species found in Argentina include M. arenaria, M. cruciani, M. decalineata, M. hapla, and M. ottersoni. The present survey is supplemented with existing published information.

  15. Hyptis uliginosa (lamiaceae en la Argentina

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    Sara G. Tressens

    2003-01-01

    Full Text Available Se cita por primera vez para la Argentina a Hyptis uliginosa, perteneciente a la sección Plagiotis. Ninguna de las tres especies de esta sección había sido mencionada aún para nuestro país. Se describe e ilustra la nueva cita y se incluye una clave para identificar las especies de Hyptis de Argentina

  16. Hyptis uliginosa (lamiaceae) en la Argentina

    OpenAIRE

    Sara G. Tressens; Keller, Héctor A.

    2003-01-01

    Se cita por primera vez para la Argentina a Hyptis uliginosa, perteneciente a la sección Plagiotis. Ninguna de las tres especies de esta sección había sido mencionada aún para nuestro país. Se describe e ilustra la nueva cita y se incluye una clave para identificar las especies de Hyptis de Argentina

  17. Transient simulations, empirical reconstructions and forcing mechanisms for the Mid-holocene hydrological climate in southern Patagonia

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Sebastian; Widmann, Martin; Jones, Julie [Institute for Coastal Research, GKSS Research Centre, Geesthacht (Germany); Haberzettl, Torsten; Ohlendorf, Christian; Zolitschka, Bernd [University of Bremen, Institute of Geography, Bremen (Germany); Luecke, Andreas; Mayr, Christoph [Research Centre Juelich, Institute of Chemistry and Dynamics of the Geosphere V, Juelich (Germany); Schaebitz, Frank [University of Cologne, Seminar for Geography and its Didactics, Cologne (Germany)

    2007-09-15

    This study investigates the atmospheric circulation in transient climate simulations with a coupled atmosphere-ocean general circulation model (GCM) for the mid-Holocene (MH) period 7-4.5 ka BP driven with combinations of orbital, solar and greenhouse gas forcings. The focus is on southern South America. Statistical downscaling models are derived from observational data and applied to the simulations to estimate precipitation in south-eastern Patagonia during the MH. These estimates are compared with lake level estimates for Laguna Potrok Aike (LPA) from sediments. Relative to pre-industrial conditions (i.e. 1550-1850), which show extraordinarily high lake levels, the proxy-based reconstructed lake levels during the MH are lower. The downscaled simulated circulation differences indicate higher LPA precipitation during the MH from March to August, higher annual means, and reduced precipitation from September to February. Thus the reconstructed lower LPA lake levels can not be explained solely by the simulated precipitation changes. Possible reasons for this discrepancy are discussed. Based on proxy data from southern South America hypotheses have also been proposed on the latitudinal position of the southern hemispheric westerlies (SHWs). In agreement with some of these hypotheses our simulations show an increased seasonal cycle of the latitudinal position of the SHWs during the MH, which can be explained by the orbital forcing. The simulations also show stronger SHWs over southern Patagonia during austral summer and weaker SHWs during winter. The downscaling model associates weaker SHWs with increased precipitation in the LPA region. However, this relationship is only moderate, and therefore the downscaling model does not support the assumption of a strong link between mean SHWs and precipitation over south-eastern Patagonia, which is the basis of many proxy-based hypotheses about the SHWs. (orig.)

  18. Comunidades de invertebrados acuáticos de mallines de Patagonia, bajo distintos niveles de antropización

    OpenAIRE

    Epele, Luis Beltrán

    2014-01-01

    En Patagonia los humedales se denominan “mallines”, palabra que en Mapuche significa área inundada o bajo donde se acumula el agua. Son una fuente importante de recursos para especies nativas terrestres y acuáticas y por ser los ambientes patagónicos de mayor productividad forrajera presentan un uso ganadero generalizado que sustenta gran parte la economía regional. Con el objetivo de evaluar las respuestas de las comunidades de invertebrados acuáticos a los diferentes niveles de antropizació...

  19. Un primitivo Notonychopidae (Litopterna del Paleoceno inferior de Punta Peligro, Chubut, Argentina

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    Morales, J.

    1997-12-01

    Full Text Available The discovery of a new ungulate species, Requisia vidmari gen. nov., nov. sp. in the lower Paleocene of Punta Peligro, Chubut (Argentine represents the earliest known record of Litopterna. The dental morphology of this new genus is very similar to that known for Notonychops powelli Soria, 1989, differing mainly by its more primitive M3, which is less elongated and less selenodont. Requisia vidmari, together with Wainka tshotshe Simpson, 1948, can be included in the family Notonychopidae, which appear to represent an ancestral grade in the evolution of Litopterna. Because cladogenesis of South American ungulates clearly took place prior to the Punta Peligro fauna and was apparently rapid, phylogenetic interpretation is difficult.Se comunica un nuevo ungulado con dentición pre-selenodonta del Paleoceno inferior, Peligrense, de Patagonia, Argentina. Su morfología dentaria es muy similar a la de Notonychops powelli Soria, 1989, pero con caracteres más primitivos. La morfología de las cúspides, el tipo de desgaste y los caracteres crescentiformes del M3 indican que Requisia vidmari gen. nov., sp. nov. presenta fuertes evidencias del desarrollo de caracteres selenodontos, por lo que se lo considera como el más primitivo representante del orden Litopterna. Requisia vidmari y probablemente Wainka tshotshe Simpson, 1948, son primitivos en relación a Notonychops, pero su similitud morfológica justificaría su inclusión en la misma familia Notonychopidae. Se considera que la radiación adaptativa de los ungulados paleocenos de América del Sur fue precoz, eventualmente rápida, lo que dificulta encontrar un modelo filogenético suficientemente explicativo.

  20. Millimeter wave radiometer installation in Río Gallegos, southern Argentina

    Science.gov (United States)

    Orte, P. F.; Salvador, J.; Wolfram, E.; D'Elia, R.; Nagahama, T.; Kojima, Y.; Tanada, R.; Kuwahara, T.; Morihira, A.; Quel, E.; Mizuno, A.

    2011-05-01

    With the aim of contribution to the study of atmospheric ozone layer, a new sensitive radiometer for atmospheric minor constituents has been installed in the Observatorio Atmosférico de la Patagonia Austral, División LIDAR, CEILAP (CITEDEF-CONICET), in October 2010. This observatory is established in the city of Rio Gallegos (51° 36' S, 69° 19' W), Argentina, close to the spring ozone hole. The millimeter wave radiometer was developed in STEL (Solar Terrestrial Environment Laboratory), Nagoya University, Japan. This passive remote sensing instrument is able to measure the ozone (O3) amount in the high stratosphere and mesosphere continuously and automatically with a high time resolution. The millimeter wave radiometer ozone profiles will be supplemented with the ozone profiles obtained from the DIAL system existent in the observatory. The millimeter wave radiometer is based on the spectral signal detection from the atmosphere due to the molecular rotational transition of molecules under study. The operation is based on a superheterodyne system which uses a Superconductor-Insulator-Superconductor (SIS) mixer receiver operating at 203.6GHz. The SIS mixer junction consists of a sandwich structure of Nb/AlOx/Nb, and is cooled to 4.2K with a closed cycle He-gas refrigerator. Two additional heterodyne-mixed stages are realized with the aim to shift the measured spectral line until a frequency around of 500 MHz. A FFT (Fast Fourier Transform) spectrometer system is used as a back end. The aims of this work are to show the potential of the millimeter wave radiometer installed in the subpolar latitudes close to the polar ozone hole and to present the preliminary result of the first measurements.

  1. Chemical and Antioxidant Properties of Wild Edible Mushrooms from Native Nothofagus spp. Forest, Argentina

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    Carolina V. Toledo

    2016-09-01

    Full Text Available This study addresses issues regarding chemical and bioactive properties of nine wild edible mushrooms from native Nothofagus forest from Patagonia, Argentina. Macronutrients, sugars, fatty acids, tocopherols, organic acids, phenolic compounds and antioxidant properties were determined. Protein was found in high levels and varied between 3.35 g/100 g dw in Cyttaria hariotii and 22.29 g/100 g dw in Lepista nuda. All of them presented mannitol and trehalose as main sugars. Mannitol was significantly higher in Ramaria patagonica, although absent in Fistulina endoxantha, whereas trehalose predominated in Aleurodiscus vitellinus, Hydropus dusenii, Cortinarius magellanicus, C. hariotii, Grifola gargal and L. nuda, ranging from 1.15 to 10.26 g/100 g dw; it was absent in R. patagonica. The major fatty acid found was linoleic acid, followed by oleic acid and palmitic acid. All species presented oxalic and fumaric acids, while some also had malic, quinic and citric acids. Tocopherols composition was variable. Cortinarius magellanicus presented significantly higher contents of both α-tocopherol and β-tocopherol. R. patagonica presented the best results in all the antioxidant activity assays (EC50 values ≤ 1 mg/mL and the highest content of phenolic compounds presenting gallic, p-hydroxybenzoic, p-coumaric and cinnamic acids. This study constitutes the first report on chemical composition and nutritional value of most of these edible mushroom species. Furthermore, it provides important information necessary to characterize and define the use of these species as gastronomic delicacies, functional foods and sources of bioactive compounds.

  2. Estructura genética en poblaciones prehispánicas del centro de Argentina

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    Fabra, Mariana

    2007-01-01

    Full Text Available Se analizan, a partir de nuevos datos craneométricos, las relaciones interpoblacionales y los roles relativos cumplidos por las fuerzas evolutivas sistemáticas vs las aleatorias en la diferenciación biológica de las poblaciones que ocuparon el actual territorio de Córdoba y otras que habitaron otras regiones geográfico-ecológicas de Argentina. La muestra está compuesta por 14 poblaciones, incluyendo 274 adultos masculinos, analizados en 10 variables craneofaciales. Se utiliza el análisis de componentes principales (PCA y el análisis de Relethford y Blangero (1990, basado en el modelo de Harpending y Ward (1982, para datos morfológicos. De acuerdo a este modelo, bajo presión sistemática uniforme, existe una correlación lineal y negativa entre la diversidad genética observada (en el caso de rasgos morfológicos se toma la variación fenotípica de forma análoga y la distancia genética de cada población a un hipotético antecesor común. El PCA muestra a Córdoba en una posición intermedia, cercana a San Luís y a otras poblaciones de las regiones pampeana y centro de Patagonia. El análisis de Relethford-Blangero ubica a Córdoba muy cercana al origen y sobre la línea de regresión, lo cual sugiere un tamaño poblacional grande y/o una separación reciente de la población ancestral, o bien la existencia de alto flujo genético con las poblaciones de las regiones mencionadas en el PCA.

  3. Guanaco’s diet and forage preferences in Nothofagus forest environments of Tierra del Fuego, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Quinteros, C.P.; Bava, J.; Gobbi, M.E.; Defossé, G.E.

    2017-11-01

    Aim of study: Guanaco (Lama guanicoe Müller), is a South American native ungulate widely distributed in Patagonia, which in the island of Tierra del Fuego (TF), extends its habitat into Nothofagus spp. forests. Within these forests, guanacos consume lenga (Nothofagus pumilio) leaves and twigs, and other understory species. The aim of this work was to determine: 1) the spring and summer diet of free ranging guanacos, and 2) which plants, grown in the forest understory, guanacos do prefer, or avoid, in these seasons of great forage abundance. Area of study: Tierra del Fuego (Argentina), on three representative areas which combined Nothofagus forests and adjacent meadows (vegas). Material and Methods: uanacos’ diet was determined by comparing epidermal and non-epidermal plant fragments with micro-histological analyses of feces. The analysis was made from composite samples of fresh feces, collected at the seasons of maximum forage productivity (spring and summer). Main results: During spring, 48% of guanacos’ diet was composed of lenga leaves, 30% of grass-like species, 15% of grasses, and less than 7% of herbs, shrubs, and lichens. In summer, 40% of the diet was composed of grasses, 30% of lenga leaves, 25% of grass-like species and the rest corresponded to herbs, shrubs, and lichens. Within the forest understory, guanaco selected lenga leaves and twigs, grass species were consumed according to their availability (or sometimes rejected), while other herbs were not consumed at all. Research highlights: Guanacos’ consumption preference for lenga, even considering the high availability of other forages, could adversely affect forest regeneration.

  4. Factors related to the attraction of flies at a biosolids composting facility (Bariloche, Argentina).

    Science.gov (United States)

    Laos, F; Semenas, L; Labud, V

    2004-07-26

    The composting process is used to treat biosolids from the Wastewater Treatment Plant of Bariloche (NW Patagonia, Argentina). Since 1998, an odourless, innocuous and stable organic amendment has been produced at the Biosolids Composting Plant of Bariloche. However, volatile compounds produced during this process, attract different vectors, mainly insects belonging to the Order Diptera, particularly in summer. To evaluate factors associated with the attraction of Diptera to composting windrows, volatile compounds, wind velocity, ambient and windrow temperatures were measured and their relationships with the taxa of flies found were determined. Sampling was conducted several months on newly formed windrows during 3 weeks of the thermophilic composting period. Composite samples from each windrow were taken on the first day of each sampling week, from November 1999 to March 2000 to analyze volatile compounds using an 'electronic nose'. Windrow and ambient temperatures and wind velocity were recorded on three consecutive days of each week, from January to March 2000; also the capture of flies was performed in this period. A weekly mean value was calculated for each environmental variable. Canonical Correspondence Analysis was employed to determine relationships between taxa of flies and the studied factors. The electronic nose discriminated among odours emitted, differentiating windrows by the bulking agent employed and by week of the thermophilic composting period. Ambient temperatures increased slightly during the sampling weeks; the highest values of wind velocity were registered during the second sampling week while windrow temperatures were sustained approximately 60 degrees C. Canonical Correspondence Analysis showed that attraction of flies to composting windrows was related to minimum and maximum ambient temperatures and volatile compounds for Muscina stabulans, Fannia sp. and Acaliptratae and to wind velocity for Ophyra sp., Sarcophaga sp., Cochliomyia

  5. Factors related to the attraction of flies at a biosolids composting facility (Bariloche, Argentina)

    Energy Technology Data Exchange (ETDEWEB)

    Laos, F.; Semenas, L.; Labud, V

    2004-07-26

    The composting process is used to treat biosolids from the Wastewater Treatment Plant of Bariloche (NW Patagonia, Argentina). Since 1998, an odourless, innocuous and stable organic amendment has been produced at the Biosolids Composting Plant of Bariloche. However, volatile compounds produced during this process, attract different vectors, mainly insects belonging to the Order Diptera, particularly in summer. To evaluate factors associated with the attraction of Diptera to composting windrows, volatile compounds, wind velocity, ambient and windrow temperatures were measured and their relationships with the taxa of flies found were determined. Sampling was conducted several months on newly formed windrows during 3 weeks of the thermophilic composting period. Composite samples from each windrow were taken on the first day of each sampling week, from November 1999 to March 2000 to analyze volatile compounds using an 'electronic nose'. Windrow and ambient temperatures and wind velocity were recorded on three consecutive days of each week, from January to March 2000; also the capture of flies was performed in this period. A weekly mean value was calculated for each environmental variable. Canonical Correspondence Analysis was employed to determine relationships between taxa of flies and the studied factors. The electronic nose discriminated among odours emitted, differentiating windrows by the bulking agent employed and by week of the thermophilic composting period. Ambient temperatures increased slightly during the sampling weeks; the highest values of wind velocity were registered during the second sampling week while windrow temperatures were sustained approximately 60 degree sign C. Canonical Correspondence Analysis showed that attraction of flies to composting windrows was related to minimum and maximum ambient temperatures and volatile compounds for Muscina stabulans, Fannia sp. and Acaliptratae and to wind velocity for Ophyra sp., Sarcophaga sp

  6. Argentina

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    Guillermina Fernández Zambón

    2005-01-01

    Full Text Available La actividad industrial, de cualquier época, tiene una gran importancia para el hombre, pues al igual que el resto de los procesos económicos, es el reflejo del accionar cotidiano de la sociedad sobre el espacio. Considerando esto, el presente articulo tiene como objetivo presentar al patrimonio industrial como recurso para organizar rutas turísticas que permitan en algunos casos recuperar espacios industriales abandonados o usar establecimientos industriales en funcionamiento pero que pueden incorporarse a este tipo de desarrollo turístico. La creación de rutas turísticas puede permitir la reactivación de las economías locales, por constituirse en definitiva en una nueva actividad económica. Para lograr esto es necesario articular el sector público y el privado. De esta forma es posible, a través de la creación de rutas turísticas del patrimonio industrial, generar un desarrollo turístico local sustentable.

  7. Geology of the epithermal Ag-Au Huevos Verdes vein system and San José district, Deseado massif, Patagonia, Argentina

    Science.gov (United States)

    Dietrich, Andreas; Gutierrez, Ronald; Nelson, Eric P.; Layer, Paul W.

    2012-03-01

    The San José district is located in the northwest part of the Deseado massif and hosts a number of epithermal Ag-Au quartz veins of intermediate sulfidation style, including the Huevos Verdes vein system. Veins are hosted by andesitic rocks of the Bajo Pobre Formation and locally by rhyodacitic pyroclastic rocks of the Chon Aike Formation. New 40Ar/39Ar constraints on the age of host rocks and mineralization define Late Jurassic ages of 151.3 ± 0.7 Ma to 144.7 ± 0.1 Ma for volcanic rocks of the Bajo Pobre Formation and of 147.6 ± 1.1 Ma for the Chon Aike Formation. Illite ages of the Huevos Verdes vein system of 140.8 ± 0.2 and 140.5 ± 0.3 Ma are 4 m.y. younger than the volcanic host rock unit. These age dates are among the youngest reported for Jurassic volcanism in the Deseado massif and correlate well with the regional context of magmatic and hydrothermal activity. The Huevos Verdes vein system has a strike length of 2,000 m, with several ore shoots along strike. The vein consists of a pre-ore stage and three main ore stages. Early barren quartz and chalcedony are followed by a mottled quartz stage of coarse saccharoidal quartz with irregular streaks and discontinuous bands of sulfide-rich material. The banded quartz-sulfide stage consists of sulfide-rich bands alternating with bands of quartz and bands of chlorite ± illite. Late-stage sulfide-rich veinlets are associated with kaolinite gangue. Ore minerals are argentite and electrum, together with pyrite, sphalerite, galena, chalcopyrite, minor bornite, covellite, and ruby silver. Wall rock alteration is characterized by narrow (220°C. Kaolinite occurring with the late sulfide-rich veinlet stage indicates pH 315°, whereas strike directions of <315° are predicted with an induced dextral strike-slip movement. The components of the structural model appear to be present on a regional scale and are not restricted to the San José district.

  8. Sedimentology and palaeontology of the Upper Jurassic Puesto Almada Member (Cañadón Asfalto Formation, Fossati sub-basin), Patagonia Argentina: Palaeoenvironmental and climatic significance

    Science.gov (United States)

    Cabaleri, Nora G.; Benavente, Cecilia A.; Monferran, Mateo D.; Narváez, Paula L.; Volkheimer, Wolfgang; Gallego, Oscar F.; Do Campo, Margarita D.

    2013-10-01

    Six facies associations are described for the Puesto Almada Member at the Cerro Bandera locality (Fossati sub-basin). They correspond to lacustrine, palustrine, and pedogenic deposits (limestones); and subordinated alluvial fan, fluvial, aeolian, and pyroclastic deposits. The lacustrine-palustrine depositional setting consisted of carbonate alkaline shallow lakes surrounded by flooded areas in a low-lying topography. The facies associations constitute four shallowing upward successions defined by local exposure surfaces: 1) a Lacustrine-Palustrine-pedogenic facies association with a 'conchostracan'-ostracod association; 2) a Palustrine facies association representing a wetland subenvironment, and yielding 'conchostracans', body remains of insects, fish scales, ichnofossils, and palynomorphs (cheirolepidiacean species and ferns growing around water bodies, and other gymnosperms in more elevated areas); 3) an Alluvial fan facies association indicating the source of sediment supply; and 4) a Lacustrine facies association representing a second wetland episode, and yielding 'conchostracans', insect ichnofossils, and a palynoflora mainly consisting of planktonic green algae associated with hygrophile elements. The invertebrate fossil assemblage found contains the first record of fossil insect bodies (Insecta-Hemiptera and Coleoptera) for the Cañadón Asfalto Formation. The succession reflects a mainly climatic control over sedimentation. The sedimentary features of the Puesto Almada Member are in accordance with an arid climatic scenario across the Upper Jurassic, and they reflect a strong seasonality with periods of higher humidity represented by wetlands and lacustrine sediments.

  9. Intertidal macrozoobenthos in sandy beaches of Bahía Nueva (Patagonia, Argentina and their use as bioindicators of environmental impact

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    Agustina Ferrando

    2010-04-01

    Full Text Available Macrozoobenthos were collected from urban sandy beaches of Puerto Madryn and adjacent areas in November 2005. Multivariate analysis techniques (ANOVA, nMDS, ANOSIM, SIMPER and RDA were used to characterize the area based on the relationships among biological and environmental variables. The areas affected by outfall of fishery factories and pluvial effluent were defined as “perturbed zones” due to the dominance of the pollution indicator polychaetes Boccardia polybranchia and Capitella “capitata” sp., which are associated with high values of ammonium, phosphates and organic matter. However, sandy beaches located 15 km from the city were considered as “unperturbed zones” because Psammodrilidae and Puelche orensanzi dominated, and they had high values of nitrates and dissolved oxygen. These taxa seem to be good candidates as indicators of clean zones for further studies. This is the first record of the family Psammodrilidae in the South Atlantic.

  10. New species of Liolaemus (Reptilia, Squamata, Liolaemini) of the Liolaemus donosobarrosi clade from northwestern Patagonia, Neuquén province, Argentina.

    Science.gov (United States)

    Avila, Luciano Javier; Perez, Cristian Hernán Fulvio; Minoli, Ignacio; Medina, Cintia Debora; Sites, Jack W Jr; Morando, Mariana

    2017-12-07

    Two new species of the Liolaemus donosobarrosi clade are described. Liolaemus tirantii sp. nov. and Liolaemus calliston sp. nov. differ from other members of their clade by a combination of coloration characters, morphometric and molecular traits. Liolaemus tirantii sp. nov. is known from three localities separated only a few kilometers from each other and Liolaemus calliston sp. nov. is known only from the type locality. Both species inhabit a region strongly impacted by oil and gas extraction but their conservation status is unknown.

  11. Comparison between remotely-sensed sea-surface temperature (AVHRR and in situ records in San Matías Gulf (Patagonia, Argentina

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    Gabriela N Williams

    2014-03-01

    Full Text Available In situ records of sea surface temperature collected between 2005 and 2009 were used to compare, for the first time, the temperature estimated by the Multichannel algorithms (MCSST of the Advanced Very High Resolution Radiometer (AVHRR sensors in San Matías Gulf, in the north of the Argentinean Patagonian Continental Shelf (between 40°47'-42°13'S. Match-ups between in situ records and satellite sea surface temperature (SST were analyzed. In situ records came from fixed stations and oceanographic cruises, while satellite data came from different NOAA satellites. The fitting of temperature data to a Standard Major Axis (SMA type II regression model indicated that a high proportion of the total variance (0.53< r² <0.99 was explained by this model showing a high correlation between in situ data and satellite estimations. The mean differences between satellite and in situ data for the full data set were 1.64 ± 1.49°C. Looking separately into in situ data from different sources and day and night estimates from different NOAA satellites, the differences were between 0.30 ± 0.60°C and 2.60 ± 1.50°C. In this paper we discuss possible reasons for the above-mentioned performance of the MCSST algorithms in the study area.

  12. The Marianas-San Marcos vein system: characteristics of a shallow low sulfidation epithermal Au-Ag deposit in the Cerro Negro district, Deseado Massif, Patagonia, Argentina

    Science.gov (United States)

    Vidal, Conrado Permuy; Guido, Diego M.; Jovic, Sebastián M.; Bodnar, Robert J.; Moncada, Daniel; Melgarejo, Joan Carles; Hames, Willis

    2016-08-01

    The Cerro Negro district, within the Argentinian Deseado Massif province, has become one of the most significant recent epithermal discoveries, with estimated reserves plus resources of ˜6.7 Moz Au equivalent. The Marianas-San Marcos vein system contains about 70 % of the Au-Ag resources in the district. Mineralization consists of Upper Jurassic (155 Ma) epithermal Au- and Ag-rich veins of low to intermediate sulfidation style, hosted in and genetically related to Jurassic intermediate composition volcanic rocks (159-156 Ma). Veins have a complex infill history, represented by ten stages with clear crosscutting relationships that can be summarized in four main episodes: a low volume, metal-rich initial episode (E1), an extended banded quartz episode with minor mineralization (E2), a barren waning stage episode (E3), and a silver-rich late tectonic-hydrothermal episode (E4). The first three episodes are interpreted to have formed at the same time and probably from fluids of similar composition: a 290-230 °C fluid dominated by meteoric and volcanic waters (-3‰ to -0‰ δ18Owater), with sulfur (-1 to -2 ‰ δ34Swater). Metal was mainly precipitated at the beginning of vein formation (episode 1) due to a combination of boiling at ˜600 to 800 m below the paleowater table, and associated mixing/cooling processes, as evidenced by sulfide-rich bands showing crustiform-colloform quartz, adularia, and chlorite-smectite banding. During episodes 2 and 3, metal contents progressively decrease during continuing boiling conditions, and veins were filled by quartz and calcite during waning stages of the hydrothermal system, and the influx of bicarbonate waters (-6 to -8.5 ‰ δ18Owater). Hydrothermal alteration is characterized by proximal illite, adularia, and silica zone with chlorite and minor epidote, intermediate interlayered illite-smectite and a distal chlorite halo. This assemblage is in agreement with measured fluid inclusion temperatures. A striking aspect of the Marianas-San Marcos vein system is that the high-grade/high-temperature veins are partially covered by breccia and volcaniclastic deposits of acidic composition, and are spatially associated with hot spring-related deposits and an advanced argillic alteration blanket. A telescoped model is therefore proposed for the Marianas-San Marcos area, where deeper veins were uplifted and eroded, and then partially covered by non-explosive, post-mineral rhyolitic domes and reworked volcaniclastic deposits, together with shallow geothermal features. The last tectonic-hydrothermal mineralization episode (E4), interpreted to have formed at lower temperatures, could be related to this late tectonic and hydrothermal activity.

  13. Variability of Soil Types in Wetland Meadows in the South of the Chilean Patagonia Variabilidad de Tipos de Suelos en Las Vegas del Sur de la Patagonia Chilena

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    Ladislava Filipová

    2010-06-01

    Full Text Available The wetland meadows and pastures (vegas of the agricultural zone of the Magallanes Region and the Chilean Patagonia are productive and intensively exploited ecosystems. However, there is scarce data about the typology and the physical and chemical properties of the soils that determine the agricultural potential of vegas sites. Sampling of the main horizons of 47 soil profiles was conducted throughout the area. The profiles were described in the field and consequently classified according to the soil typology system of the WRB (IUSS Working Group WRB, 2006. Analyses of bulk and particle densities, capillary water capacity, pH (H2O, pH (CaCl2, texture, organic material, C:N ratio, electrical conductivity, effective cation exchange capacity, N, P, Ca-Mg-K-Na, exchangeable Al,  extractable Al, sulfur SO4(2-, B, and micronutrients (Cu-Zn-Mn-Fe were carried out.  The most frequently recorded groups of soil types in the studied vegas were Histosols - peat soils (20 profiles, and Fluvisols (19. Gleysols (3, Vertisols (1, Regosols (3, Solonchaks (1 and Solonetzs (1 were detected with much less frequency. There is also considerable variability in soil properties among and within the groups of soil types. The principal differences between the Histosols and the Fluvisols are the content of organic matter (often peat, pH level (related to the absence/presence of carbonates and associated soil properties. Fluvisols are more susceptible to salinization under conditions of aridity, whereas the main threat to Histosols is artificial drainage.Las praderas húmedas (vegas de la zona de uso agropecuario de la Región de Magallanes y la Antártica Chilena son ecosistemas productivos e intensamente explotados. No obstante, los conocimientos de los factores edáficos que determinan el potencial de las vegas son escasos. En este trabajo se realizó el muestreo de los horizontes principales de 47 perfiles del suelo de distintos tipos de vegas de la zona. Los perfiles

  14. Distribución del diseño de las cabezas mascariformes en las representaciones rupestres del centro oeste argentino y del norte chico chileno: estilo, identidad y paisaje = Distribution of mask-like forms design in rock art of centre west of Argentina and

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    Gabriela Inés Sabatini

    2015-11-01

    Full Text Available Se llevó a cabo un análisis sobre las representaciones rupestres del sitio Tunduqueral emplazado en el Valle de Uspallata, N.O de la Provincia de Mendoza, Argentina, ubicado en el periodo agroalfarero temprano-medio (siglos IV y X d.C.Basándonos en la relación entre arte y paisaje y en los conceptos teóricos sobre estilos tecnológicos buscamos comprender la materialidad de lo ritual a través del análisis comparativo de las cabezas mascariformes del Cerro Tunduqueral con las representaciones de sitios de San Juan: Los Colorados de Barreal, Quebrada de Aguas Blancas, Villa Dominguito en Sierra Pie de Palo y Quebrada La Chilca, y los hallados en el Norte Chico de Chile: Valle El Encanto (Ovalle, Llano - Pabellón de San Agustín (Valle del río Hurtado Superior y Río Grande (Cuenca del río Limarí.Consideramos que la recurrencia de los diseños a ambos lados de la cordillera de los Andes estaría mostrando ciertos vínculos  (lazos comunitarios, de parentesco o vecindad entre los grupos que ocuparon esta macrorregión, que persistieron y fueron recreados, pero que con el tiempo cobraron significaciones diferentes al ser incorporados a contextos políticos, económicos e ideológicos disímiles del original. Esto nos hablaría de una estrategia de comunicación visual entre puntos distantes a través de códigos simbólicos comunes.Rock art analysis had made of Tunduqueral site locate in Uspallata’s valley, NW of Mendoza, Argentina, during farmland-pottery early-late period (4th and 10th centuries AC.Based on the relationship between art, landscape and theoretical concepts of technological styles we expect to understand the ritual material by the comparative analysis of mask-like forms in Tunduqueral’ hill with the San Juan representations: Los Colorados de Barreal, Quebrada de Aguas Blancas, Villa Dominguito in Sierra Pie de Palo y Quebrada La Chilca, and Small North of Chile: Valle El Encanto (Ovalle, Llano–Pabellón de San

  15. Mountain frozen grounds as small amplitude thermal proxy in southern continental Patagonia

    Science.gov (United States)

    Ruiz, Sebastian; Beriain, Eneko; Izagirre, Eñaut; Bockheim, James; Pedro, Cid-Agüero

    2015-04-01

    Frozen grounds are an important element of the cryosphere, covering between a 20-25% of the global area. Frozen grounds are becoming a relevant object of research in the southern hemisphere, being most studies focused mainly on Antarctica. With the exception of seasonally frozen grounds, perennially frozen ground is found in continental South America, for example, in high altitude terrains from 4.600m a.s.l. in central Chile. However, scarce or not information regarding permafrost on Southern Patagonia has been reported. One of the aims of this study was to establish mountain permafrost existence at 1.200m in the southern limit of the Southern Patagonian Ice-Field, a geographically active area surrounded by different kinds of glaciers on fast retreat. The area of study presents several features of past cryogenic activity such as undefined polygonal grounds with a thick clast border and sandy-loam interior. A scarce vegetal cover is limited to lichen and moss communities. The analyzed soil does not represent a thermal barrier that may avoid heat wave dynamic along the ground profile. There was neither significant snow-cover during winter nor a vegetation layer enough to consider as insulation for the analyzed ground. Oscillations above 0°C were evidenced down to 1.8m depth during winter of 2014, ruling out the existence of permafrost at that lower limit. Year round thermal dynamic down to 1.8m in the ground profile is presented as one result of the monitoring. Small amplitude temperature fluctuations were registered upon monitoring. These minimal amplitudes were stable throughout several months and as such serve as an interesting proxy for recent and long-term climatic thermal fluctuation. The influence of winds coming from nearby glaciers highly affects near-surface amplitude. This interaction was studied. The present work is part of an ongoing monitoring network along South America that intends to fill the gap between tropical Andes and the Antarctic Peninsula.

  16. Pleistocene glaciation leaves deep signature on the freshwater crab Aegla alacalufi in Chilean Patagonia.

    Science.gov (United States)

    Xu, Jiawu; Pérez-Losada, Marcos; Jara, Carlos G; Crandall, Keith A

    2009-03-01

    Quaternary glacial cycles have played an important role in shaping the biodiversity in temperate regions. This is well documented in Northern Hemisphere, but much less understood for Southern Hemisphere. We used mitochondrial DNA and nuclear elongation factor 1α intron sequences to examine the Pleistocene glacial impacts on the phylogeographical pattern of the freshwater crab Aegla alacalufi in Chilean Patagonia. Phylogenetic analyses, which separated the glaciated populations on eastern continent into a north group (seven populations) and a south group (one population), revealed a shallow phylogenetic structure in the north group but a deep one in the non-glaciated populations on western islands, indicating the significant influence of glaciation on these populations. Phylogenies also identified the Yaldad population on Chiloé Island as a potentially unrecognized new species. The non-glaciated populations showed higher among population genetic divergence than the glaciated ones, but lower population genetic diversity was not detected in the latter. The two glaciated groups, which diverged from the non-glaciated populations at ~96,800-29,500 years ago and ~104,200-73,800 years ago, respectively, seem to have different glacial refugia. Unexpectedly, the non-glaciated islands did not serve as refugia for them. Demographic expansion was detected in the glaciated north group, with a constant population increase after the last glacial maximum. Nested clade analyses suggest a possible colonization from western islands to eastern continent. After arriving on the continent and surviving the last glacial period there, populations likely have expanded from high to low altitude, following the flood of melting ice. Aegla alacalufi genetic diversity has been primarily affected by Pleistocene glaciation and minimally by drainage isolation.

  17. INCORPORACIÓN DEL PAISAJE EN LA GESTIÓN DEL TERRITORIO DE LA PATAGONIA CHILENA

    Directory of Open Access Journals (Sweden)

    MARÍA DOLORES MUÑOZ

    2014-01-01

    Full Text Available Este artículo presenta una metodología para el análisis y gestión del paisaje en la Patagonia chilena, un territorio que se destaca por la belleza y diversidad de los paisajes del agua generados por la presencia de grandes lagos, ríos, fiordos, humedales y campos de hielo. El primer caso de estudio es una investigación para evaluar las potencialidades turísticas y territoriales de los paisajes del agua en la cuenca del río Baker. Se utiliza una metodología interdisciplinaria y técnicas de medición, cualitativa y cuantitativa, que permitieran analizar los valores espaciales, ambientales, territoriales y culturales asociados al paisaje. Un aspecto esencial fue incorporar la valoración social del paisaje. El segundo caso, ubicado en el estrecho de Magallanes, corresponde a una metodología de análisis territorial como base para diseñar un Plan de Manejo Turístico en el Área Marina Protegida Francisco Coloane (que incluye al Parque Marino Francisco Coloane. Comprende el análisis de las condiciones ambientales, las características del paisaje y potencialidades del turismo de intereses especiales asociado al paisaje para respaldar la propuesta de gestión. En ambos casos, la metodología considera al paisaje como principal recurso territorial y plantea una forma de gestión respaldada por principios de sustentabilidad ambiental y social.

  18. Biomarkers of environmental stress in gills of ribbed mussel Aulacomya atra atra (Nuevo Gulf, Northern Patagonia).

    Science.gov (United States)

    Giarratano, Erica; Gil, Mónica N; Malanga, Gabriela

    2014-09-01

    In this study, we assessed in gills of native ribbed mussels Aulacomya atra atra from three sites within Nuevo Gulf (Northern Patagonia) several biomarkers such as reactive oxygen species (ROS), lipid radicals (LR), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST) and metallothionein (MT). Furthermore, concentrations of main trace metals (Fe, Al, Zn, Cu, Cd and Pb) were quantified in mussel tissue. Results showed significant induction of SOD, GST, MT and MDA, as well as, higher concentration of Fe, Al and Cd in winter than in summer. The high MDA content measured in mussels from Folías Wreck seemed to be caused by the very high levels of Fe that would come from the corrosion of the vessel. Mussels from the control site Punta Cuevas presented the lowest levels of Cd and the highest of Al in winter. Despite positive correlations were found between Al and GST and MT, no spatial differentiation was detected in those biomarkers. On the other hand, MT was only related to Al been most likely influenced by environmental variables than by the trace metals. It has to be highlighted that the relationship detected among water temperature, nutrients and antioxidant responses in gills is probably related to the fact that this tissue is in direct contact with water and it is sensitive to its fluctuations. Taking into account that mussel gill is a tissue actively proliferating and the first target of contaminants present in water, so that changes in its antioxidant system can provide an earlier warning signal than in other tissues. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Novel aromatic ring-hydroxylating dioxygenase genes from coastal marine sediments of Patagonia

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    Ferrero Marcela A

    2008-03-01

    Full Text Available Abstract Background Polycyclic aromatic hydrocarbons (PAHs, widespread pollutants in the marine environment, can produce adverse effects in marine organisms and can be transferred to humans through seafood. Our knowledge of PAH-degrading bacterial populations in the marine environment is still very limited, and mainly originates from studies of cultured bacteria. In this work, genes coding catabolic enzymes from PAH-biodegradation pathways were characterized in coastal sediments of Patagonia with different levels of PAH contamination. Results Genes encoding for the catalytic alpha subunit of aromatic ring-hydroxylating dioxygenases (ARHDs were amplified from intertidal sediment samples using two different primer sets. Products were cloned and screened by restriction fragment length polymorphism analysis. Clones representing each restriction pattern were selected in each library for sequencing. A total of 500 clones were screened in 9 gene libraries, and 193 clones were sequenced. Libraries contained one to five different ARHD gene types, and this number was correlated with the number of PAHs found in the samples above the quantification limit (r = 0.834, p nahAc-like genes, phnAc-like genes as identified in Alcaligenes faecalis AFK2, and phnA1-like genes from marine PAH-degraders from the genus Cycloclasticus. Conclusion These results show the presence of hitherto unidentified ARHD genes in this sub-Antarctic marine environment exposed to anthropogenic contamination. This information can be used to study the geographical distribution and ecological significance of bacterial populations carrying these genes, and to design molecular assays to monitor the progress and effectiveness of remediation technologies.

  20. Lake-level variations and tides in Lago Argentino, Patagonia: insights from pressure tide gauge records

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    Andreas Richter

    2015-08-01

    Full Text Available Based on precise pressure tide gauge observations lake-level records are derived for two sites in Lago Argentino, southern Patagonia, of 2.5 and 1 years of duration. Applying the tools of time series analysis, the principal processes affecting the lake level are identified and quantified. Lake-level changes reflecting variations in lake volume are dominated by a seasonal cycle of 1.2 m in amplitude. Lake-volume changes occur in addition with a daily period in response to melt water influx from surrounding glaciers. Sporadic lake-volume jumps are caused by bursting of the ice dam of Perito Moreno glacier. Water movements in Lago Argentino are dominated by surface seiches reaching 20 cm in amplitude. Lake tides reach a maximum amplitude of 3 mm. The comparison of the tidal signal extracted from the lake-level observations with a model composed of the contributions of body tide and ocean tidal loading indicates a phase shift of 23° which is most likely explained by an 1 hour phase lag of global ocean tide models in the region of the highly fragmented Pacific coast. The comparison of the obtained results with those of a previous study of Lago Fagnano, Tierra del Fuego, allows to relate differences in the hydrological and hydrodynamic processes between both lakes to morphological properties. This leads to a tentative prediction of the lake-level variability to be expected from other great Patagonian lakes. The presented geodetic results shall serve as a starting point for a detailed limnological investigation of these aquatic ecosystems.

  1. Toxigenic potential of Fusarium graminearum isolated from maize of northwest Argentina

    Science.gov (United States)

    Sampietro, D.A.; Apud, G.R.; Belizán, M.M.E.; Vattuone, M.A.; Catalán, C.A.N.

    2013-01-01

    Twenty six isolates of Fusarium graminearum from grains of maize hybrids harvested in ±west Argentina were grown on autoclaved rice grain to assess their ability to produce type B trichothecenes. Chemical analysis indicated that 38% of isolates were nivalenol (NIV) producers only, 31% were major NIV producers with high DON(deoxynivalenol)/NIV ratios, 8% were major DON producers with minor NIV production, and 23% were DON producers only. Isolates showed a high variability in their toxigenic potential which was not related to fungal biomass. The distribution of the different chemotypes as well as the high and the low trichothecene-producing Fusarium isolates could not be associated to a geographical origin. Our results confirmed for the first time that isolates of Fusarium graminearum from maize of northwest Argentina are able to produce DON and NIV. A substancial contamination with both NIV and DON is likely in maize from northwest Argentina. Their contents should be quantified in regional surveillances for mycotoxin contamination. PMID:24294230

  2. Spatial distribution of the daily rainfall concentration index in Argentina: comparison with other countries

    Science.gov (United States)

    Llano, María Paula

    2017-08-01

    The precipitation is a meteorological variable studied in Argentina mainly in annual, seasonal and monthly scales. Its variability is a significant climate element and also a critical socioeconomic factor. This study aims to contribute to the knowledge of daily rainfall in Argentina. Daily records of precipitation for 66 stations provided by the Servicio Meteorológico Nacional are used (period 1991-2014). The spatial distribution of the annual precipitation presents an east-west gradient in the north of the country. In monthly scale, there are different precipitation distributions such as a double maximum in the centre-east zone or a single maximum in the northwest in summer time and in the southern Andes range during the winter. To carry out the study, the concentration index (CI) of daily precipitation with a resolution of 1 mm is used. Precipitation in Argentina, given its vast territory, presents a great variability with a wide range of rainfall regimes; CI values are found between 0.54 and 0.68. These values are categorized as high (greater than 0.61) and low (less than 0.58). The north of the country and the Atlantic coast show the highest CI values. The lower values are present in the Andes range and in the south of the country. The results are compared with other studies in the world.

  3. Molecular phylogeography of the Chagas' disease vector Triatoma infestans in Argentina

    Science.gov (United States)

    Pérez de Rosas, A R; Segura, E L; García, B A

    2011-01-01

    Triatoma infestans is the main vector of Chagas' disease in South America between latitudes 10°S and 46°S. A multilocus microsatellite data set of 836 individuals from 27 populations of T. infestans, from all its range of distribution in Argentina, was analyzed. Our results favor the hypothesis of two independent migration events of colonization in Argentina and secondary contacts. The majority of the populations of the western provinces of Catamarca, La Rioja, San Juan and the west of Cordoba province, had almost no shared ancestry with the rest of the populations analyzed. Probably those populations, belonging to localities close to the Andean region, could have been established by the dispersal line of T. infestans that would have arrived to Argentina through the Andes, whereas most of the rest of the populations analyzed may have derived from the dispersal line of T. infestans in non-Andean lowlands. Among them, those from the provinces of Formosa, Chaco, Santiago del Estero and Santa Fe shared different percentages of ancestry and presented lower degree of genetic differentiation. The migratory movement linked to regional economies and possibly associated with passive dispersal, would allow a higher genetic exchange among these populations of T. infestans. This study, using microsatellite markers, provides a new approach for evaluating the validity of the different hypotheses concerning the evolutionary history of this species. Two major lineages of T. infestans, an Andean and non-Andean, are suggested. PMID:21224874

  4. A review of genus Nysius Dallas in Argentina (Hemiptera: Heteroptera: Orsillidae).

    Science.gov (United States)

    Pall, José Luis; Kihn, Romina Gisela; Diez, Fernando

    2016-06-29

    The orsillid genus Nysius Dallas is a complex and large genus with more than 100 described species worldwide, and includes many species of agricultural importance, one such example is N. simulans (Stål) from Argentina. Three species of Nysius are found in this country: N. simulans (Stål), N. irroratus (Spinola) and N. puberulus Berg. The material available for the present study, consisting of over 610 specimens, was collected by sweep-net, G-Vac and light trap in the provinces of Chubut (42° to 46°S; 63.5° to 72° W), La Pampa (35º to 39º south; 63º to 68º West), Neuquén (36° to 41° S; 68° to 71°W) and Río Negro (37° to 42°S; 62° to 71°W), in the central region of Argentina, during the years 2010-2014. Although the species N. simulans is frequently recorded as a pest of soybean crop, there exist no detailed description but only a brief general diagnosis. In the present contribution, therefore, we provide a detailed redescription as well as an updated distribution of N. simulans and N. irroratus, and a key for species of genus Nysius present in Argentina.

  5. Toxigenic potential of Fusarium graminearum isolated from maize of northwest Argentina

    Directory of Open Access Journals (Sweden)

    D.A. Sampietro

    2013-01-01

    Full Text Available Twenty six isolates of Fusarium graminearum from grains of maize hybrids harvested in ±west Argentina were grown on autoclaved rice grain to assess their ability to produce type B trichothecenes. Chemical analysis indicated that 38% of isolates were nivalenol (NIV producers only, 31% were major NIV producers with high DON(deoxynivalenol/NIV ratios, 8% were major DON producers with minor NIV production, and 23% were DON producers only. Isolates showed a high variability in their toxigenic potential which was not related to fungal biomass. The distribution of the different chemotypes as well as the high and the low trichothecene-producing Fusarium isolates could not be associated to a geographical origin. Our results confirmed for the first time that isolates of Fusarium graminearum from maize of northwest Argentina are able to produce DON and NIV. A substancial contamination with both NIV and DON is likely in maize from northwest Argentina. Their contents should be quantified in regional surveillances for mycotoxin contamination.

  6. Net accumulation rates derived from ice core stable isotope records of Pío XI glacier, Southern Patagonia Icefield

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    M. Schwikowski

    2013-10-01

    Full Text Available Pío XI, the largest glacier of the Southern Patagonia Icefield, reached its neoglacial maximum extent in 1994 and is one of the few glaciers in that area which is not retreating. In view of the recent warming it is important to understand glacier responses to climate changes. Due to its remoteness and the harsh conditions in Patagonia, no systematic mass balance studies have been performed. In this study we derived net accumulation rates for the period 2000–2006 from a 50 m (33.2 4 m weq ice core collected in the accumulation area of Pío XI (2600 m a.s.l., 49°16'40"S, 73°21'14"W. Borehole temperatures indicate near temperate ice, but the average melt percent is only 16 ± 14%. Records of stable isotopes are well preserved and were used for identification of annual layers. Net accumulation rates range from 3.4–7.1 water equivalent (m weq with an average of 5.8 m weq, comparable to precipitation amounts at the Chilean coast, but not as high as expected for the Icefield. Ice core stable isotope data correlate well with upper air temperatures and may be used as temperature proxy.

  7. Southern Annular Mode-like changes in southwestern Patagonia at centennial timescales over the last three millennia

    Science.gov (United States)

    Moreno, Patricio I.; Vilanova, I.; Villa-Martínez, R.; Garreaud, R. D.; Rojas, M.; de Pol-Holz, R.

    2014-07-01

    Late twentieth-century instrumental records reveal a persistent southward shift of the Southern Westerly Winds during austral summer and autumn associated with a positive trend of the Southern Annular Mode (SAM) and contemporaneous with glacial recession, steady increases in atmospheric temperatures and CO2 concentrations at a global scale. However, despite the clear importance of the SAM in the modern/future climate, very little is known regarding its behaviour during pre-Industrial times. Here we present a stratigraphic record from Lago Cipreses (51°S), southwestern Patagonia, that reveals recurrent ~200-year long dry/warm phases over the last three millennia, which we interpret as positive SAM-like states. These correspond in timing with the Industrial revolution, the Mediaeval Climate Anomaly, the Roman and Late Bronze Age Warm Periods and alternate with cold/wet multi-centennial phases in European palaeoclimate records. We conclude that SAM-like changes at centennial timescales in southwestern Patagonia represent in-phase interhemispheric coupling of palaeoclimate over the last 3,000 years through atmospheric teleconnections.

  8. La expedición de Ramón de Clairac a la Patagonia en 1798

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    Juan Alfonso Maeso Buenasmañanas

    1999-01-01

    Full Text Available El siglo XVIII presenció la organización y ejecución por parte de las potencias europeas de ambiciosos viajes marítimos intercontinentales con finalidades científicas, estratégicas y de prestigio. España no permaneció ajena a este fenómeno, y la dinastía borbónica con Carlos III a la cabeza, promovió un vasto plan de expediciones que abarcaron amplias regiones del planeta y pretendieron atender a un complejo conjunto de intereses y necesidades. La Patagonia, situada en el extremo austral del continente americano, a pesar de pertenecer teóricamente a la corona española, era un territorio virtualmente vacío de presencia europea.In the Eighteenth century, European powers organized and carried out some ambitious maritime expeditions, aiming at scientific, strategic and prestige-getting goals. Spain did not stand aside in this question, and the Bourbon dinasty, especially Caries III, prometed a vast plan of expeditions, many of them embracing large regions of the worid, and intended to meet a complex series of needs and interests. Patagonia, situated in the southern end of the American continent, was, although theorically a Spanish possession, an empty territory lacking and European population.

  9. 77 FR 45653 - Lemon Juice From Argentina and Mexico

    Science.gov (United States)

    2012-08-01

    ...)] Lemon Juice From Argentina and Mexico Institution of five-year reviews concerning the suspended investigations on lemon juice from Argentina and Mexico. AGENCY: United States International Trade Commission... the suspended investigations on lemon juice from Argentina and Mexico would be likely to lead to...

  10. A promising location in Patagonia for paleoclimate and paleoenvironmental reconstructions revealed by shallow firn core from Monte San Valentin (Northern patagonia Icefield, Chile)

    DEFF Research Database (Denmark)

    Vimeux, F.; de Angelis, M.; Ginot, P.

    2008-01-01

    The study of past climate variability from ice core investigations has been largely developed both in polar areas over the past decades and, more recently, in tropical regions, specifically along the South American Andes between 0° and 20°S. However a large gap still remains at mid...... is that the San Valentín site is not only influenced by air masses originating from the southern Pacific and directly transported by the prevailing west winds but also by inputs from South American continental sources from the E-NE, sometimes mixed with circumpolar aged air masses, the relative influence...

  11. Mycorrhizal compatibility and symbiotic reproduction of Gavilea australis, an endangered terrestrial orchid from south Patagonia.

    Science.gov (United States)

    Fracchia, Sebastián; Aranda-Rickert, Adriana; Flachsland, Eduardo; Terada, Graciela; Sede, Silvana

    2014-11-01

    Gavilea australis is a terrestrial orchid endemic from insular south Argentina and Chile. Meeting aspects of mycorrhizal fungi identity and compatibility in this orchid species is essential for propagation and conservation purposes. These knowledge represent also a first approach to elucidate the mycorrhizal specificity of this species. In order to evaluate both the mycorrhizal compatibility and the symbiotic seed germination of G. australis, we isolated and identified its root endophytic fungal strains as well as those from two sympatric species: Gavilea lutea and Codonorchis lessonii. In addition, we tested two other strains isolated from allopatric terrestrial orchid species from central Argentina. All fungal strains formed coilings and pelotons inside protocorms and promoted, at varying degrees, seed germination, and protocorm development until seedlings had two to three leaves. These results suggest a low mycorrhizal specificity of G. australis and contribute to a better knowledge of the biology of this orchid as well as of other sympatric Patagonian orchid species, all of them currently under serious risk of extinction.

  12. Soil and Terrain Database for Argentina, primary data (version 1.0) - scale 1:1 million (SOTER_Argentina)

    NARCIS (Netherlands)

    Dijkshoorn, J.A.; Huting, J.R.M.

    2014-01-01

    The Soil and Terrain database for Argentina primary data (version 1.0), at scale 1:1 million (SOTER_Argentina), was compiled of enhanced soil information within the framework of the FAO's program Land Degradation Assessment in Drylands (LADA). Primary soil and terrain data for Argentina were

  13. de la Argentina y notas nomenclaturales

    Directory of Open Access Journals (Sweden)

    Zulma E. Rúgolo de Agrasar

    2006-01-01

    Full Text Available En esta primera revisión del género Deyeuxia para la Argentina se reconocen 58 taxones nativos de América, tres de ellos son endémicos de la Argentina, y los restantes también crecen en Bolivia, Brasil y Chile. Se describen tres nuevos taxones para la ciencia: Deyeuxia alba subsp. breviaristata (Argentina, Brasil y Uruguay; Deyeuxia heterophylla var. puberilemma (Perú; Deyeuxia trichodonta var. hirsuta (Argentina: Salta. Se establece un nuevo nombre: Deyeuxia nana, para en Agrostis caespitosa. Las siguientes once entidades constituyen nuevas citas para Argentina, Bolivia, Chile y Ecuador: Deyeuxia brevifolia var. brevifolia y Deyeuxia brevifolia var. expansa (Chile; Deyeuxia cabrerae var. cabrerae, D. cabrerae var. aristulata (Chile; D. cabrerae var. trichopoda (Chile; Deyeuxia curta (Ecuador; Deyeuxia filifolia (Chile; D. diemii (Chile; Deyeuxia filifolia (Chile; Deyeuxia hackelii (Chile; Deyeuxia minima (Argentina y Ecuador; Deyeuxia sclerantha (Ecuador; Deyeuxia spicigera var. spicigera (Chile; Deyeuxia spicigera var. cephalotes (Argentina y Deyeuxia trichodonta var. trichodonta (Bolivia. Se establecen cinco nuevas combinaciones: Deyeuxia reitzii, Deyeuxia rupestris f. pilosa., Deyeuxia rupestris var. minor, D. tarmensis var. macrochaeta y Deyeuxia velutina var. nardifolia. Se adicionan nuevos sinónimos en las siguientes entidades: Deyeuxia heterophylla (Calama grostis mulleri, Calamagrostis macbridei; Deyeuxia rupestris f. pilosa (Calamagrostis leonardii, Calamagrostis longearistata f. pilosa y Calamagrostis epigeios (Calamagrostis chilensis. Esta revisión incluye una evaluación crítica de los caracteres morfológicos (algunos estudiados con MEB con valor taxonómico para Deyeuxia y sus especies aquí estudiadas, como también una discusión de las relaciones de Deyeuxia con sus géneros más afines. Se presentan en detalle consideraciones nomenclaturales sobre taxones problemáticos, claves dicotómicas para distinguir Deyeuxia de

  14. Peat decomposition records in three pristine ombrotrophic bogs in southern Patagonia

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    T. Broder

    2012-04-01

    Full Text Available Ombrotrophic bogs in southern Patagonia have been examined with regard to paleoclimatic and geochemical research questions but knowledge about organic matter decomposition in these bogs is limited. Therefore, we examined peat humification with depth by Fourier Transformed Infrared (FTIR measurements of solid peat, C/N ratio, and δ13C and δ15N isotope measurements in three bog sites. Peat decomposition generally increased with depth but distinct small scale variation occurred, reflecting fluctuations in factors controlling decomposition. C/N ratios varied mostly between 40 and 120 and were significantly correlated (R2 > 0.55, p < 0.01 with FTIR-derived humification indices. The degree of decomposition was lowest at a site presently dominated by Sphagnum mosses. The peat was most strongly decomposed at the driest site, where currently peat-forming vegetation produced less refractory organic material, possibly due to fertilizing effects of high sea spray deposition. Decomposition of peat was also advanced near ash layers, suggesting a stimulation of decomposition by ash deposition. Values of δ13C were 26.5 ± 2‰ in the peat and partly related to decomposition indices, while δ15N in the peat varied around zero and did not consistently relate to any decomposition index. Concentrations of DOM partly related to C/N ratios, partly to FTIR derived indices. They were not conclusively linked to the decomposition degree of the peat. DOM was enriched in 13C and in 15N relative to the solid phase probably due to multiple microbial modifications and recycling of N in these N-poor environments. In summary, the depth profiles of C/N ratios, δ13C values, and FTIR spectra seemed to reflect changes in environmental conditions affecting decomposition, such as bog wetness, but were dominated by site s