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Sample records for chubut patagonia argentina

  1. 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.

  2. Depositional Environments of Late Danian Plant Localities: Chubut Provice, Patagonia, Argentina

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    Comer, E.; Slingerland, R. L.; Wilf, P.

    2010-12-01

    Diverse, well-preserved macroflora are observed within Cretaceous and Paleocene sediments of Chubut Province, Patagonia, Argentina. These macroflora are the most well preserved early Paleocene flora from Gondwana and add new insight into the diversity and environments of that epoch. Two major sites of fossil preservation, Palacio de los Loros and Parque Provincial Ormachea, sit near the top of the Late Danian (65.5-61.7 Ma) Salamanca Formation. Understanding the depositional history of the Salamanca is important in characterizing paleoenvironments in which these flora lived and relating these Patagonian macroflora to concurrent Paleocene flora within the Gondwanan supercontinent. During a two week field season, twenty stratigraphic sections were measured along the outcrop belt at Palacio de los Loros and Ormachea Park as well as two minor sites; Las Flores, and Rancho Grande. Photo mosaics, laser ranger data, and stratigraphic columns were merged with elevated geologic maps and imported into Fledermaus to generate a 3-D visualization of facies relationships. Rock samples were also collected and will be thin sectioned and analyzed for petrography and grain size. The Salamanca Fm. consists of 7 facies, listed here in stratigraphically ascending order: 1)Transgressive sands, 2)Wispy-bedded claystone, 3)Banco Verde, 4)White Cross bedded sandstone, 5)Accretion set siltstone, 6)Transitional silty claystone and 7)Banco Negro. Based on these facies, the Salamanca Fm. is interpreted as a marine-shelf to brackish, tide-dominated, estuarine deposit. The base of the Salamanca Fm. rests on an unconformity representing a marine flooding surface and lower sections of the Salamanca, facies 1 and 2, contain abundant glauconite and fossils indicative of a marine shelf environment. These facies give way upwards to bi-directional trough cross bedded sandstones interspersed with flaser bedded sandy siltstones (facies 3 and 4) indicating a less marine estuary with strong flow regimes

  3. Plantas Medicinales en el Parque Nacional los alerces, Chubut, Patagonia Argentina

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    Carolina Toledo

    2012-12-01

    Full Text Available El objetivo de este estudio fue identificar las plantas con valor medicinal empleadas por los antiguos pobladores del Parque Nacional Los Alerces y relacionarlas con la riqueza específica de plantas medicinales presentes en el área. Se entrevistaron 16 pobladores asentados en la Reserva Nacional que tenían conocimiento de las plantas medicinales, más allá de que hicieran uso o no de las mismas. Las entrevistas fueron semiestructuradas, completadas de manera escrita e individual por el entrevistador. Las mismas incluían diez preguntas que recopilaban información respecto a las especies usadas como medicina, modo de preparación y aplicación, frecuencia de uso, localización de las plantas en el ámbito del área protegida, forma de obtención de las especies, y el modo de adquisición de los conocimientos respecto a las plantas. Los pobladores mencionaron el uso de 42 especies con valor medicinal, distribuidas en 24 familias, de las cuales las mejor representadas fueron Lamiaceae (21,4% y Asteraceae (14,2%. En cuanto al origen de las plantas medicinales citadas por los pobladores, el 58, 5% correspondió a especies exóticas. Los usos más frecuentes fueron para trastornos del sistema digestivo, seguido en orden decreciente y en menor proporción para tratar afecciones respiratorias, cardiovasculares y de la piel. Al comparar la riqueza total de especies medicinales presentes en el Parque y las registradas a partir de las entrevistas, se observa que se hace uso de un 28,6% de lo disponible en el área.Medicinal plants in The Alerces National Park, Chubut, Argentinean Patagonia. The aim of this study was to identify the medicinal plants used by the old residents in The Alerces National Park and to relate this information with medicinal species richness in the area. An interview was employed with 16 local people settled in the National Reserve who had knowledge of medicinal plants, past or not to make use of them. The interviews were semi

  4. Avulsion at a drift-dominated mesotidal estuary: The Chubut River outlet, Patagonia, Argentina

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    Isla, Federico; Espinosa, Marcela; Rubio, Belén; Escandell, Alejandra; Gerpe, Marcela; Miglioranza, Karina; Rey, Daniel; Vilas, Federico

    2015-10-01

    The Chubut River flows from the Andes to the Atlantic Ocean, and is interrupted by a single dam built at the middle valley. The lower valley is dominated by the aggradation of an alluvial plain induced by a complex of spits that enclosed the inlet in the last 5000 years. The river has reduced its flow because the blocking of the upper basin by terminal moraines during the Upper Pleistocene. At least the last two marine transgressions have flooded this estuary, and contributed to the aggradation during regressions. The area is of particular interest in regard to irrigation channels practiced since the XIX century. Today, the mean monthly flow is less than 10 m3/s although peaks of 95 m3/s have been recorded in Gaiman in July 2001. The dynamics of the estuary is dominated by waves (wave-dominated estuary) as tidal effects attenuate in less than 5 km. Three vibracores were collected within this floodplain: (a) at Gaiman, an area without any effect of the sea (35 km from the coast); (b) at Trelew, at the former avulsion plain of the river (18 km from the coast); and (c) at Playa Magagna, a saltmarsh located 0.4 km from the beach. At the Gaiman core (1.54 m long) fresh-water epiphytic diatoms dominate (Epithemia sorex, Cocconeis placentula, Ulnaria ulna) suggesting the aggradation of an alluvial plain. The Trelew core (2.19 m long) was collected from a deltaic plain. It was composed by fine sand with organic matter at the base that evolved into silty layers to the top. Several unconformities and laminae with heavy minerals were detected by their geochemical composition analysed by micro X-ray fluorescence (Itrax XRF core scanner). Fine-sand laminated layers were perfectly detected by their high content in S and Cl. On the other hand, mud layers presented lower content in Mg and Al with increments in Ca and V. The core from the marsh area (1.67 m long) was analysed in terms of the diatom evolution in order to detect Holocene sea-level and salinity effects. The sand flats

  5. 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.

  6. Patagonia Argentina

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    A.J. Acuña

    2008-01-01

    Full Text Available 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 los que se les realizó tratamientos diferentes. En uno se monitoreo la atenuación natural del sistema, en otro la fertilización con nitrógeno (N, fósforo (P y potasio (K, y en el último la fertilización con P y K. Durante el seguimiento se determinaron mineralización y medición de hidrocarburos, y se realizaron recuentos bacterianos y determinación de nitrato, nitrito y amonio. Los resultados indican que es posible la biodegradación de hidrocarburos en el suelo deficiente de nitrógeno de la Patagonia estudiado en tiempos mas prolongados que en aquellos que se realiza una fertilización con nitrógeno. El nitrógeno necesario para el proceso sería obtenido por los microorganismos del suelo por fijación biológica.

  7. Circulación, intercambio y uso de obsidianas en la costa de la provincia del Chubut (Patagonia argentina, durante el Holoceno tardío

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    Julieta Gómez Otero

    2005-12-01

    Full Text Available Se presentan los resultados de un nuevo análisis de elementos traza en 26 artefactos de 19 sitios arqueológicos de la costa de la provincia del Chubut. Dieciocho sitios son del sector norte, entre las desembocaduras del Arroyo Verde y del río Chubut y el último está situado al sur, en Cabo Dos Bahías. Seis diferentes tipos de obsidiana fueron identificados; tres de ellos de fuentes conocidas: los tipos T/SCI de la fuente de Telsen y SI de la fuente Sacanana, ambas del centro-norte de la provincia del Chubut y el tipo PDAI de la fuente de Pampa del Asador, en la provincia de Santa Cruz. Los tipos de fuente desconocida son: CC? anteriormente determinado en un sitio arqueológico de Cerro Castillo, margen suroeste de la Meseta de Somuncurá; el tipo T/SCII, en principio considerado como subtipo de la fuente de Telsen, pero según estos nuevos análisis pertenece a una fuente distinta; y un tipo nuevo, MSI, cuya fuente estaría en la Meseta de Somuncurá. La información aquí presentada indica que los seis diferentes tipos de obsidiana llegaron a la costa central de Patagonia desde centros de aprovisionamiento independientes y desde distancias variables entre 100 km y 800 km.The results of analyses of trace-elements in twenty-six samples of obsidian from 19 archaeological sites along the Atlantic coast, between Golfo San Matías Oeste (41°55´58.8´´S and Cabo Dos Bahías (44°54´77.9´´S are presented as a contribution to studies of sources and distribution of obsidian in archaeological sites in central Patagonia, specifically the province of Chubut, Argentina. Six different types of obsidian occur in this collection, three of which come from known obsidian sources. Four of the samples are chemically similar to obsidian type T/SCI, which is derived from near Sierra Negra (42°21'S - 66°36´W, northeast of the town of Telsen, and is located between 100 and 235 km linear distance west of the sites along the coast in which this obsidian

  8. Determination of Quality Chemical Parameters of Honey from Chubut (Argentinean Patagonia Determinación de Parámetros Químicos de Calidad de las Mieles de Chubut (Patagonia Argentina

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    Pia Valeria Aloisi

    2010-12-01

    Full Text Available This study was intended to evaluate the quality chemical parameters of 62 Apis mellifera L. honey samples, from the Province of Chubut, Argentine. Samples were obtained from the three melliferous areas of this province: Andean region, lower Chubut River valley and plains of Senguerr River. The average values obtained for electrical conductivity (0.33 mS cm-1 and pH (4.17 indicate that the analyzed honeys came mainly from nectar. Electrical conductivity was higher in honeys from the Andean region than in honeys from the other two regions. Moisture (water content was low, with an average value of 14.67%. The hydroxymethylfurfural (HMF content was very low and ranged between 0.0 and 14.70 mg kg-1. Moisture, HMF and free acidity values show good maturity and absence of undesirable fermentation in all the samples. Diastase activity had a mean value of 13.50 units on the Gothe scale. Color parameter presented variations between honeys from different areas. The analytical values for the samples from the Andean region, the lower Chubut River valley and the plains of the Senguerr River respectively were: 67.73, 40.33 and 23.26 mm Pfund. Results obtained in this study, indicate that honeys produced in Chubut present excellent quality properties according to international standards.Este estudio se realizó para evaluar los parámetros químicos de calidad de 62 muestras de mieles de Apis mellifera L., provenientes de la Provincia de Chubut. Las muestras de mieles se obtuvieron de las tres regiones melíferas de esta provincia: la Región Andina, el valle inferior del Río Chubut y la llanura del Río Senguerr. Los valores promedio obtenidos para conductividad eléctrica (0,33 mS cm-1 y pH (4,17 indican que las mieles fueron principalmente de néctar. Los valores de conductividad eléctrica fueron mayores en las mieles de la Región Andina que en las mieles de las otras regiones. La humedad (contenido de agua fue baja, con un valor medio de 14,67%. El

  9. Trichothurgus bolithophilus sp. n. (Hymenoptera, Megachilidae a bee nesting in horse manure pads in Patagonia, Argentina

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    Laura Sarzetti

    2012-10-01

    Full Text Available A new species of Trichothurgus, described herein, T. bolitophilus sp. n., nests in dry horse manure pads in Chubut, Patagonia, Argentina. The simplest nests consisted of one main tunnel ending in a series of 2 cells without partitions between them. In the more complex ones up to 6 cells were connected laterally to the main tunnel. Nests showed signs of reutilization. The behavior of nesting in horse manure is described for the first time in bees.

  10. Presence of Pleurotus ostreatus in Patagonia, Argentina.

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    Lechner, Bernardo Ernesto; Petersen, Ronald; Rajchenberg, Mario; Albertó, Edgardo

    2002-06-01

    Specimens belonging to the genus Pleurotus were collected growing on fallen trunks of Araucaria araucana, a native tree with a poorly known mycoflora, which grows in Patagonia, Argentina. Fruitbodies were produced in culture on sawdust from an isolated strain. Interspecific pairing tests performed between mating types of Pleurotus from Patagonia and tester strains of P. pulmonarius and P. ostreatus showed the Patagonia strain to be 100% compatible with P. ostreatus and incompatible with P. pulmonarius. Dikaryons obtained on sawdust were fertile, since they were able to produce fruitbodies and viable spores. This is the first documented record of P. ostreatus from Argentina and the first gilled fungus found growing on Araucaria araucana. PMID:12828514

  11. Sifonápteros parásitos de los roedores Sigmodontinos de la Patagonia norte de la Argentina: estudios sistemáticos y ecológicos

    OpenAIRE

    2013-01-01

    El objetivo del presente trabajo fue contribuir al conocimiento de la diversidad de los sifonápteros parásitos de roedores sigmodontinos de la provincia del Chubut (Patagonia Norte, Argentina), con énfasis sistemático y con el fin de interpretar las relaciones parásito-hospedador-ambiente

  12. Tourism, Transnationality and Ethnolinguistic Vitality: The Welsh in the Chubut Province, Argentina

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    Johnson, Ian

    2010-01-01

    This article aims to develop the concept of ethnolinguistic vitality by adopting a qualitative approach to vitality rather than the statistical approach traditionally used. Ten small-size focus group style interviews were held with members of the Welsh-Argentinean community in the Chubut Province in the south of Argentina in order to explore…

  13. 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.

  14. Geophysical characterization of circular structures in Chubut and Mendoza (Argentina): Impact vs. Volcanism

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    Prezzi, C.; Orgeira, M. J.; Risso, C.; Acevedo, R.; Ponce, F.; Nullo, F.; Martinez, O.; Rabassa, J.; Margonari, L.; Corbella, H.

    2013-05-01

    This work focuses on two main objectives. One of them is to provide information to discern the genesis of the circular structures present in Bajada del Diablo (Chubut, Argentina) considered as impact craters, and the other one is to contribute to a better knowledge of the circular structures located in the volcanic fields of Llancanelo and Payunia (Mendoza, Argentina). Chubut circular structures have been attributed to the collision of an extraterrestrial body, possibly an asteroid. However, doubts persist about their genesis because of the lack of direct geological evidences. Since detailed geomorphological studies have ruled out an origin by wind deflation, the prevailing alternative hypothesis attributes these circular structures to a volcanic process. On the other hand, the study of the volcanic fields of Payunia and Llancanelo (Mendoza) will contribute to the knowledge of the mechanics of hydromagmatic processes in the area, and the origin of circular structures morphologically similar to those located in Chubut. In the Payunia volcanic field at least 27 cones with evidences of hydromagmatism, in a field of more than 800 pure magmatic cones, have been recognized. This study tries to determine if a relationship between the observed volcanic circular structures and participation of water during the eruption exists. Magnetic and gravity field surveys of the circular volcanic structures in Llancanelo and Payunia volcanic fields were performed in order to determine their relationship with the type of eruption. Electromagnetic, magnetic and gravity field surveys were also carried out in Chubut circular structures. The comparative analysis of geological and geophysical results obtained in the circular structures of Chubut and those obtained in the circular structures in the volcanic areas of Llancanelo and Payunia suggest an impact origin for the circular structures of Chubut.

  15. Un ejemplo excepcional de brechamiento (sismita? en el grupo Chubut, Patagonia An exceptional example of brecciation (seismite? in the Chubut Group, Patagonia

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    Edgardo Navarro

    2010-10-01

    Full Text Available Un brechamiento excepcional en unidades sedimentarias pelíticas del Grupo Chubut en la cercanía de la localidad de Telsen, provincia de Chubut, muestra que han sido afectadas por una etapa de telodiagénesis (diagénesis de exhumación. Presentan evidencias de deformación frágil relacionadas con mecanismos de sobrepresurización. Estos depósitos de edad aptiana, se disponen subhorizontales y constituyen asociaciones fluviales lateralmente extendidas. Un continuo de estructuras sedimentarias deformacionales se desarrollan enteramente sobre los depósitos pelíticos correspondientes a la asociación de facies de llanura de inundación. Cuatro intervalos fueron reconocidos de manera continua: 1 fracturado in situ, 2 brechado, 3 brechado fangosostenido y 4 homogeneizado. Conductos de escape potenciales de diversos tamaños, tienen desarrollo en el intervalo fangosostenido, que en ocasiones llegan a atravesar el intervalo superior homogéneo. El mecanismo de sobrepresurización, se habría visto favorecido por la presencia de cuerpos de areniscas conglomerádicas tobáceas confinantes (capa sello, que impidieron el escape de fluidos, permitiendo la licuefacción parcial a total y fluidización de la rocas sedimentarias de la llanura aluvial. Fallas normales reconocidas en el área, que afectan al Grupo Chubut, constituirían un elemento de juicio para establecer un origen sísmico a estas fábricas brechadas, cuya magnitud habría superado M>5 de la escala Mercalli modificada. La característica reológica frágil del material a partir del cual se originaron, convierte a estas estructuras en un ejemplo natural excepcional de brechamiento a partir de un mecanismo de sobrepresurización fosilizado.Sedimentary units of the Chubut Group in the proximity of the Telsen locality, in Chubut province affected by a telodiagenesis stage, display evidence of brittle deformation related to over-pressurizing mechanisms. These sub-planar deposits of Aptian age

  16. Primer registro de diplostomiasis ocular en trucha arco iris cultivada en Patagonia (Argentina First record of diplostomiasis in cultured rainbow trout in Patagonia (Argentina

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    L. SEMENAS

    1998-01-01

    Full Text Available Se describe por primera vez para la Patagonia argentina un caso de diplostomiasisocular o catarata verminosa en peces de un establecimiento de críaen estanques en la provincia de Chubut. Para el diagnóstico se analizaroncaracoles (Chilina dombeiana por técnica de aplastamiento y truchasarco iris (Oncorhynchus mykiss por técnica de necropsia con microdisecciónde ojos. El hallazgo de esporocistos de Diplostomidae en el hepatopáncreasde los caracoles y de metacercarias de Diplostomum sp. en los cristalinosde los peces, permitió diagnosticar que la catarata era de origenparasitario. Se detallan las recomendaciones dadas para el control y laprevención de la enfermedad, basadas en métodos ecológicosteniendo en cuenta fundamentalmente el ciclo del parásito y lascaracterísticas de las instalaciones de la piscicultura. Este trabajoamplía la distribución de esta enfermedad en trucha arcoiris cultivada hasta el sur de ArgentinaA case of ocular diplostomiasis (parasite cataract in fish or eyefluke disease is described for the first time in a pisciculture with earth ponds in the province of Chubut. Snails (Chilina dombeiana were analysed by squashing and rainbow trout (Oncorhynchus mykiss by necropsy with microdissection of eyes, for the diagnosis. The findings of sporocysts of Diplostomidae in the hepatopancreas of snails and metacercariae of Diplostomum sp. in the lens of fish confirm the cataract as parasitic. Detailed recommendations for the control and prevention of the disease, based mainly on ecological methods, taking into account the cycle of the parasite and the characteristics of the building of the pisciculture are given. This paper amplifies the distribution of this disease in cultured rainbow trout, including the southern part of South America

  17. A Tenebrionid beetle’s dataset (Coleoptera, Tenebrionidae from Peninsula Valdés (Chubut, Argentina

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    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

  18. Mortalidad en la población galesa de Gaiman, provincia de Chubut, Argentina

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    Caratini, Alicia Liliana

    2005-01-01

    Full Text Available El objetivo de este trabajo es analizar la evolución en el tiempo de las defunciones y de las causas de muerte por edad y sexo de la población galesa de Gaiman, provincia de Chubut, Argentina. Los datos fueron obtenidos de las Actas de Defunción del Archivo del Registro Civil de la ciudad de Rawson, Chubut. El período de estudio se extendió de 1892 a 1961 y para su descripción y análisis se lo dividió en decenios. Se registraron 2103 defunciones de las cuales 1039 (49% correspondieron a galeses y sus descendientes, lo cual representa un promedio de 14.6 muertes por año. Se detectó una sobremortalidad masculina (59%, esperable en una población colonizadora con predominio de varones. Se observó un incremento, en el tiempo, de la edad media de defunción, lo que indica mejoras en las condiciones socioeconómicas y de salud de la población. La mortalidad infantil y los natimortos representaron el 20% y el 11%, respectivamente, de las defunciones y se constató una transición desde una mortalidad provocada por enfermedades de naturaleza exógena a otra de causalidad endógena. Al compararse nuestros datos con los de la provincia de Chubut y el país, se comprobó, en todos los casos, un descenso de la mortalidad en el tiempo, aunque en Gaiman esa disminución fue más significativa, probablemente por la atención que la comunidad le dedicaba a la educación y a la salud.

  19. Un ejemplo excepcional de brechamiento (sismita? en el grupo Chubut, Patagonia

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    Edgardo Navarro

    2010-10-01

    Full Text Available Un brechamiento excepcional en unidades sedimentarias pelíticas del Grupo Chubut en la cercanía de la localidad de Telsen, provincia de Chubut, muestra que han sido afectadas por una etapa de telodiagénesis (diagénesis de exhumación. Presentan evidencias de deformación frágil relacionadas con mecanismos de sobrepresurización. Estos depósitos de edad aptiana, se disponen subhorizontales y constituyen asociaciones fluviales lateralmente extendidas. Un continuo de estructuras sedimentarias deformacionales se desarrollan enteramente sobre los depósitos pelíticos correspondientes a la asociación de facies de llanura de inundación. Cuatro intervalos fueron reconocidos de manera continua: 1 fracturado in situ, 2 brechado, 3 brechado fangosostenido y 4 homogeneizado. Conductos de escape potenciales de diversos tamaños, tienen desarrollo en el intervalo fangosostenido, que en ocasiones llegan a atravesar el intervalo superior homogéneo. El mecanismo de sobrepresurización, se habría visto favorecido por la presencia de cuerpos de areniscas conglomerádicas tobáceas confinantes (capa sello, que impidieron el escape de fluidos, permitiendo la licuefacción parcial a total y fluidización de la rocas sedimentarias de la llanura aluvial. Fallas normales reconocidas en el área, que afectan al Grupo Chubut, constituirían un elemento de juicio para establecer un origen sísmico a estas fábricas brechadas, cuya magnitud habría superado M>5 de la escala Mercalli modificada. La característica reológica frágil del material a partir del cual se originaron, convierte a estas estructuras en un ejemplo natural excepcional de brechamiento a partir de un mecanismo de sobrepresurización fosilizado.

  20. Influencia de Especies Arbóreas Implantadas sobre Parámetros Biológicos y Bioquímicos en un Suelo Forestal de Chubut, Argentina Influence of Implanted tree Species on Biological and Biochemical Parameters in a Forest soil of Chubut, Argentina

    Directory of Open Access Journals (Sweden)

    Diana N Effron

    2012-01-01

    Full Text Available Se estudió la influencia de algunas especies forestales sobre propiedades biológicas y bioquímicas de un suelo, con el propósito de contribuir a establecer criterios que logren un desarrollo sustentable para un sistema forestal. El sitio de estudio es un suelo forestal de Chubut, en la Patagonia Argentina. Se tomaron muestras superficiales de suelo de tres parcelas con una especie dominante cada una: Roble (Quercus robur, Fresno (Fraxinus excelsior L. y Pino radiata (Pinus radiata D. Don.. En ellas se determinaron carbono de respiración, actividad deshidrogenasa, actividad fosfatasa ácida, número de bacterias totales y amilolíticas, actinomicetes y hongos totales, mientras que en las hojas se determinó fósforo. Los resultados mostraron diferencias importantes de estos parámetros para las diferentes especies estudiadas, diferencias que son explicadas por la composición química de las diferentes especies vegetales.The influence of some tree species on biological and biochemical properties of a forest soil was studied with the purpose of establishing criteria to achieve a sustainable development of a forest system. The study site is a forest soil of Chubut, in the Argentinean Patagonia. Surface soil samples were taken of three plots with a dominant species each one: Oak (Quercus robur, Ash (Fraxinus excelsior L. and Radiata Pine (Pinus radiata D. Don.. Microbial respiration, dehydrogenase and acid phosphatase activities, counts of aerobic and amylolytic bacteria, actinomyces and fungi were determined in soil samples, while phosphorous was determines in leaves. The results showed important differences of these parameters for the different species considered in the study, differences that are explained by the different chemical composition of the vegetal species.

  1. Wind regime and wind power in North Patagonia, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Palese, C.; Laessig, J.L.; Cogliati, M.G.; Bastanski, M.A. [Universidad Nacional del Comahue, Buenos Aires (Argentina). Facultad de Ingenieria

    2000-07-01

    The present paper discusses wind and wind power characteristics in a region north of 40{sup o}S (North Patagonia, Argentina) as well as wind power projects sustainability. Extreme wind episodes influence most economic and social regional activities. Mean flow pattern was studied in three North Patagonia sites: Neuquen, Mari Menuco and Cutral-Co, by sampling analysis of wind direction and intensity during a year. Gusts were quantified and strong winds were studied. Available meteorological power was also estimated. It was observed that North Patagonia is a place of great wind power potential. However, the energy available, which is related to prevailing strong winds, is also associated to high gust occurrence which certainly restricts exploitation. (Author)

  2. Notes on Erysiphales (Ascomycetes) from Patagonia, Argentina

    OpenAIRE

    Havrylenko, Maria; Takamatsu, Susumu

    2005-01-01

    Fifteen Erysiphaceous taxa found on 20 host plant species in Patagonia are documented. A new species Oidium maculatae (type host: Viola maculata) is described. Berberis linearifolia, Buddleja globosa, Prosopis alpataco and Viola maculata, are new host plants for Erysiphales.Three new combinations on fungi and host plant species were founded: Erysiphe howeana – Fuchsia magellanica; E.patagoniaca – Nothofagus pumilio and N. antarctica. The genus Sawadaea and the species S. bicornis on Acer negu...

  3. Change in the meiofauna community structure of sandy beaches of the Nuevo Gulf (Chubut, Argentina

    Directory of Open Access Journals (Sweden)

    Carlos A. Harguinteguy

    2012-01-01

    Full Text Available The composition and distribution of the benthic meiofauna assemblages of the Nuevo Gulf (Chubut, Argentina are described in relation to abiotic variables. The meiofauna and sediment samples were collected in the intertidal zone of four sandy beaches with different anthropic disturbances in June 2005. The samples were obtained at 20 sampling sites using a 2.5 cm diameter core tube at a depth of 10 cm. A total of 13 meiofauna taxa were identified, with the meiofauna being primarily represented by nematodes, gastrotrichs, ciliates and polychaetes and the meiofauna abundances ranging from 1.5 × 10³ to 6.5 × 10³ ind. 10 cm‑2. Univariate (one-way ANOVA test and multivariate (ANOSIM/MDS test analyses showed clear dissimilarities in community structures between sites with anthropic effects and those in pristine condition, revealed by the significant differences were found between beaches near to and far way from a city with port activity. The meiofaunal assemblage varied in abundance and diversity, and these changes in the community structure may have been related to environmental gradients on the shore. The BIO‑ENV analysis showed that the redox potential discontinuity depth might be the main factor in the spatial distribution of organisms.

  4. 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

    2016-01-01

    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). PMID:27395893

  5. Eriocóccidos (Hemiptera: Coccoidea encontrados en la Patagonia Argentina Eriococcidae (Hemiptera: Coccoidea found in Patagonia Argentina

    Directory of Open Access Journals (Sweden)

    Patricia González

    2004-07-01

    Full Text Available Se listan cuatro géneros y nueve especies de eriocóccidos presentes en la Patagonia argentina, sobre distintos huéspedes. Chilecoccus browni Miller & González, Chilecoccus spinossus Miller & González, Eriococcus novarinoensis Hoy, Eriococcus rhadinothrix Miller & González, Icelococcus nothofagi Miller & González, sobre Nothofagus dombeyi (Fagaceae. Eriococcus chilensis Miller & González, Eriococcus eurythrix Miller & González, Icelococcus charlini Miller & González, sobre Nothofagus antarctica. Eriococcus eurythrix Miller & González sobre Nothofagus alpina. Icelococcus charlini Miller & González sobre Nothofagus obliqua. Stibococcus cerinus Miller & González sobre Myrceugenia exsucca (Myrtaceae.We list four genera and nine species of eriococcid present in the Patagonia Argentina, on different hosts. Chilecoccus browni Miller & González, Chilecoccus spinossus Miller & González, Eriococcus novarinoensis Hoy, Eriococcus rhadinothrix Miller & González, Icelococcus nothofagi Miller & González, on Nothofagus dombeyi (Fagaceae. Eriococcus chilensis Miller & González, Eriococcus eurythrix Miller & González, Icelococcus charlini Miller & González, on Nothofagus antarctica. Eriococcus eurythrix Miller & González on Nothofagus alpina. Icelococcus charlini Miller & González on Nothofagus obliqua. Stibococcus cerinus Miller & González on Myrceugenia exsucca (Myrtaceae.

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

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    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.

  7. 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. PMID:25148081

  8. Root proliferation in native perennial grasses of arid Patagonia, Argentina

    Institute of Scientific and Technical Information of China (English)

    Yanina A. TORRES; Mara M. MUJICA; Sandra S. BAIONI; Jos ENTO; Mara N. FIORETTI; Guillermo TUCAT; Carlos A. BUSSO; Oscar A. MONTENEGRO; Leticia ITHURRART; Hugo D. GIORGETTI; Gustavo RODRGUEZ; Diego BENTIVEGNA; Roberto E. BREVEDAN; Osvaldo A. FERNNDEZ

    2014-01-01

    Pappophorum vaginatum is the most abundant C4 perennial grass desirable to livestock in rangelands of northeastern Patagonia, Argentina. We hypothesized that (1) defoliation reduce net primary productivity, and root length density and weight in the native species, and (2) root net primary productivity, and root length density and weight, are greater in P. vaginatum than in the other, less desirable, native species (i.e., Aristida spegazzinii, A. subulata and Sporobolus cryptandrus). Plants of all species were either exposed or not to a severe defoliation twice a year during two growing seasons. Root proliferation was measured using the cylinder method. Cylindrical, iron structures, wrapped up using nylon mesh, were buried diagonally from the periphery to the center on individual plants. These structures, initially filled with soil without any organic residue, were dug up from the soil on 25 April 2008, after two successive defoliations in mid-spring 2007. During the second growing season (2008-2009), cylinders were destructively harvested on 4 April 2009, after one or two defoliations in mid-and/or late-spring, respectively. Roots grown into the cylinders were obtained after washing the soil manually. Defoliation during two successive years did reduce the study variables only after plants of all species were defoliated twice, which supported the first hypothesis. The greater root net primary productivity, root length den-sity and weight in P. vaginatum than in the other native species, in support of the second hypothesis, could help to explain its greater abundance in rangelands of Argentina.

  9. 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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Variation in external morphology of resident bottlenose dolphins (Tursiops truncatus) in Bahia San Antonio, Patagonia, Argentina.

    OpenAIRE

    Vermeulen, Els; Cammareri, Alejandro

    2010-01-01

    Two geographic variations of bottlenose dolphins were described in Argentina (Bastida & Rodriguez, 2003); bottlenose dolphins characterized by their triangular dorsal fin shape (coast of the province of Buenos Aires), and bottlenose dolphins characterized by their falcate dorsal fin shape (coast of the province of Chubut). It was stated that `their clear difference would indicate that both geographic forms are isolated¿ (Bastida & Rodriguez, 2003 p.137). A photo-identification study carrie...

  12. Mineralogical data on angelaite, Cu2AgPbBiS4, from the Los Manantiales District, Chubut, Argentina

    DEFF Research Database (Denmark)

    Topa, D.; Paar, W.H.; Putz, H.;

    2010-01-01

    0.97Pb1.05Bi1.00S3.91. The ideal formula (on the basis of nine atoms) is Cu2AgPbBiS4, which requires Cu 16.31, Ag 13.84, Pb 26.58, Bi 26.81, S 16.45, total 100 wt.%. Angelaite is orthorhombic, with a 12.734(5), b 4.032(1), c 14.633(5) Å, V 751.8(5) Å3, space group Pnma and Z = 4. The calculated......Angelaite, ideally Cu2AgPbBiS4, occurs as a hypogene mineral in polymetallic ores at the Ángela groups of veins in the mining district of Los Manantiales, in the province of Chubut, Argentina. The new mineral species is predominantly associated with pyrite, sphalerite, chalcopyrite, hematite...

  13. La Formación Continua de los docentes alfabetizadores: la evolución de sus planteamientos didácticos de atención a la diversidad en el aula. Análisis de un colectivo docente de la Escuela Municipal 3 de Puerto Madryn, Patagonia Argentina

    OpenAIRE

    Contín, Silvia

    2006-01-01

    Consultable des del TDX Títol obtingut de la portada digitalitzada Esta tesis doctoral estudia desde un paradigma naturalista interpretativo la evolución del pensamiento de un grupo de profesores alfabetizadores que desarrollan su tarea en una escuela urbano marginal de la ciudad de Puerto Madryn, Chubut, Patagonia Argentina. Cuenta con la dirección académica del Dr Arturo Noguerol Rodrigo, del departamento de didáctica de la Lengua, la Literatura y las Ciencias Sociales de la Universid...

  14. Mercury in the biotic compartments of Northwest Patagonia lakes, Argentina.

    Science.gov (United States)

    Rizzo, A; Arcagni, M; Arribére, M A; Bubach, D; Guevara, S Ribeiro

    2011-06-01

    We report on total mercury (THg) concentrations in the principal components of food webs of selected Northern Patagonia Andean Range ultraoligotrophic lakes, Argentina. The THg contents were determined using Instrumental Neutron Activation Analysis in muscle and liver of four fish species occupying the higher trophic positions (the introduced Salmo trutta, Oncorhynchus mykiss and Salvelinus fontinalis, and the native Percichthys trucha) accounted for eight lakes belonging to Nahuel Huapi and Los Alerces National Parks. We studied the food web components of both the West and East branches of Lake Moreno, including benthic primary producers such as biofilm, mosses, and macrophytes, three plankton fractions, fish, riparian tree leaves, and benthic invertebrates, namely decapods, molluscs, insect larvae, leeches, oligochaetes, and amphipods. Mercury concentrations in fish muscle varied in a wide range, from less than 0.05 to 4 μg g(-1) dry weight (DW), without a distribution pattern among species but showing higher values for P. trucha and S. fontinalis, particularly in Lake Moreno. The THg contents of the food web components of Lake Moreno varied within 4 orders of magnitude, with the lower values ranging from 0.01 to 0.5 μg g(-1) DW in tree leaves, some macrophytes, juvenile salmonids or benthic macroinvertebrates, and reaching concentrations over 200 μg g(-1) DW in the plankton. Juvenile Galaxias maculatus caught in the pelagic area presented the highest THg contents of all fish sampled, reaching 10 μg g(-1) DW, contents that could be associated with the high THg concentrations in plankton since it is their main food source. Although Lake Moreno is a system without local point sources of contamination, situated in a protected area, some benthic organisms presented high THg contents when compared with those from polluted ecosystems. PMID:21421254

  15. Age and composition of granulite xenoliths from Paso de Indios, Chubut province, Argentina

    NARCIS (Netherlands)

    Castro, Antonio; Aragon, Eugenio; Diaz-Alvarado, Juan; Blanco, Idael; Garcia-Casco, Antonio; Vogt, Katharina; Liu, D-Y.

    2011-01-01

    Granulite xenoliths enclosed in Paleogene alkali basalts from the locality of Paso de Indios in The Argentinean Patagonia, have been studied for petrology, geochemistry and U–Pb SHRIMP zircon geochronology. These are lower crust xenoliths composed of pyroxene and plagioclase dominantly. Symplectitic

  16. 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.

  17. AN IDENTIFICATION STUDY ON BOTTLENOSE DOLPHINS (TURSIOPS TRUNCATUS) IN NORTHEAST PATAGONIA, ARGENTINA

    OpenAIRE

    Vermeulen, Els; Cammareri, Alejandro; Failla, Mauricio; Holsbeek, Ludo

    2008-01-01

    In Argentina, bottlenose dolphin (Tursiops truncatus) sightings decreased notably since the late 80s in regions where it used to be frequent to observe them. Nowadays, Northeast Patagonia is one of the few regions where they still can be seen frequently, although local increasing human activities result in increasing need for information. In general, photo-identification has been established as a helpful tool in cetacean research. However, only few studies have applied this method to bottlen...

  18. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. 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

  1. Mosasaurs (Reptilia) from the late Maastrichtian (Late Cretaceous) of northern Patagonia (Río Negro, Argentina)

    Science.gov (United States)

    Fernández, Marta; Martin, James; Casadío, Silvio

    2008-03-01

    A diverse assemblage of mosasaurs was recently recovered from the Jagüel Formation (late Maastrichtian) exposed at three localities of northern Patagonia (Río Negro, Argentina). Four taxa (three mosasaurines and a plioplatecarpine) have been identified, and three of these marine reptiles can be identified at lower taxonomic levels: Mosasaurus sp. aff. M. hoffmanni, Plioplatecarpus sp., and Prognathodon sp. These occurrences are significant because they represent the first diagnostic material at generic level exhumed from Patagonia and include one of the youngest mosasaurs found worldwide. One of the specimens described herein was found only 1.5 m below the Cretaceous/Tertiary boundary. Only mosasaurs from Antarctica found within a meter of the boundary are known to occur higher in the geologic section.

  2. Colonization potential of the genus Ulva (Chlorophyta, Ulvales in Comodoro Rivadavia Harbor (Chubut, Argentina

    Directory of Open Access Journals (Sweden)

    2005-01-01

    Full Text Available Temporal and spatial changes in the coverage of five Ulva L. species (U. prolifera O.F. Müller, U. intestinalis L., U. hookeriana (Kützing Hayden et al., U. compressa L. and U. linza L. were analyzed on rocky substrata experimentally immersed in Comodoro Rivadavia Harbor (Argentina. Colonization was studied during an annual period at three levels: upper intertidal, middle intertidal and subtidal. Coverage was significantly higher in the middle intertidal and subtidal levels than in the upper intertidal level, where all species of Ulva were absent. Seasonal changes were also significant: coverage in summer and spring was significantly higher than in autumn and winter. Most species showed high spatial variability among replicates from the same level and season. Zonation patterns within the harbor differed from those observed in natural areas, probably due to low wave exposure and its interaction with herbivory and desiccation stress. Colonization patterns observed in this study indicate niche segregation in closely related species of the genus Ulva.

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

    Directory of Open Access Journals (Sweden)

    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

  4. A widespread devonian methamorphic episode in northern Patagonia, Argentina

    International Nuclear Information System (INIS)

    One of the greatest difficulties in Rb-Sr dating on metamorphic rocks is the lack of evidences of complete re-homogenization and the assumption of a common initial ratio for all the samples analyzed. The redistribution of parent-daughter elements and the concomitant partial or complete equilibration of the isotopic system could occur on mineral or regional size domains. This fact led to many authors to discard or disapprove the use of this method in metamorphic terranes. However, recent papers suggested that this opinion has been premature and that additional information could be obtained by the Rb-Sr method despite the difficulties that it implies (Patel et al., 1999). Many reports on well fitted Rb-Sr isochrons giving the age of metamorphism in regionally metamorphosed rocks, suggest that the Sr isotopic equilibrium can take place at different scales. This paper presents data and the Rb-Sr system behaviour from a metamorphic unit (Cushamen Formation) in the Northern Patagonia, as a contribution to elucidate the evolution of the North Patagonian Massif (au)

  5. Exploring options for farm-level strategic and tactical decision-making in fruit production systems of South Patagonia Argentina

    NARCIS (Netherlands)

    Cittadini, E.D.; Lubbers, M.T.M.H.; Ridder, de N.; Keulen, van H.; Claassen, G.D.H.

    2008-01-01

    In South Patagonia, Argentina, sweet cherry is the main fruit-tree crop grown for export, resulting in a highly seasonal labour demand. Managers of deciduous perennial fruit orchards must consider both biological and economic relationships in selecting crop species and orchard design. This makes dec

  6. Evaluation of an indirect elisa for the diagnosis of bovine brucellosis in Patagonia, Argentina

    International Nuclear Information System (INIS)

    Control and eradication of bovine brucellosis is usually based on the serological detection of antibodies. In Argentina, the Rose Bengal test (RB) and the Buffered Plate antigen test (BPA) are the two screening test officially recognized, while the 2-mercaptoethanol test (2ME) and the Tube Agglutination test (SAT) are the confirmatory assays currently in use. In order to improve the serological diagnosis of bovine brucellosis in Patagonia, Argentina, an indirect ELISA kit produced by the Joint FAO/IAEA Division was evaluated. Sera from negative non-vaccinated, negative but vaccinated and positive animals were tested by all the above techniques. The specificity of the I-ELISA (99.6% and 99.7%) was similar to that of the BPA, RB, 2ME and Complement Fixation test (CF) when used to test sera from non-vaccinated, negative and vaccinated, negative animals, respectively. The sensitivity of the I-ELISA (98%) was higher than the BPA test (96%) and the CF test (95,2%). The I-ELISA kit evaluated in this study was thought to be a valuable tool for the diagnosis of bovine brucellosis in Patagonia region where little epidemiological information is available about this disease and where large numbers of sera should be tested to obtain such information. (author)

  7. Rehabilitation of oiled magellanic penguins (Spheniscus magellanicus) in Patagonia, Argentina

    International Nuclear Information System (INIS)

    On September 10, 1991, the International Bird Rescue Research Center (IBRRC) was contacted by Dee Boersma, professor of zoology at the University of Washington. An oil spill from an unknown source had affected large numbers of magellanic penguins (Spheniscus magellanicus) returning to breeding colonies along the coast of southern Argentina. Dr. Boersma had been studying the penguins at Punta Tombo since 1982. It wasn't unusual for some of the penguins to arrive oiled, but this year the numbers of oiled birds were up considerably. In the week of September 14 to 20, a survey of 239 kilometers of coastline (about one-third of the affected area) spotted 16,350 penguins with some degree of oiling

  8. 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

    Directory of Open Access Journals (Sweden)

    C.A. Robles

    2000-01-01

    Full Text Available 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 inmunofluorescencia. De este mismo órgano se aisló posteriormente Clostridium novyi tipo B. Ante la falta del predisponente más comúnmente citado, Fasciola hepatica, se postula que el severo parasitismo por Thysanosoma actinioides fue el factor desencadenante de este brote de hepatitis infecciosa necrosanteAn outbreak of Black disease in Argentinean Patagonia where 80 sheep out of 1200 Merino ewes suddenly died, is reported. Big amounts of fluid in the thoracic and abdominal cavities, the presence of focal coagulative necrosis in the liver parenchyma and plenty Thysanosoma actinioides specimens in bile ducts were the most important findings observed at necropsy. Clostridium novyi was early detected in liver smears through immunofluorescence. Later, Clostridium novyi type B was isolated from liver cultures. Due to the absence of the commonest predisposing agent, i.e. Fasciola hepatica, the severe parasitism by Thysanosoma actinioides is proposed as the predisposing factor of the present outbreak of Black disease

  9. Angelaíta en la paragénesis del distrito Los Manantiales, provincia del Chubut: Una nueva especie mineral Angelaite in the paragenesis of Los Manantiales district, Chubut, Argentina: a new mineral species

    Directory of Open Access Journals (Sweden)

    M.K. de Brodtkorb

    2004-12-01

    Full Text Available Angelaíta, Cu2AgPbBiS2 , una nueva especie mineral, fue localizada en la mina Ángela, mineralización de tipo IS del distrito Los Manantiales, Chubut, Argentina. La paragénesis incluye esfalerita, pirita, calcopirita, galena y en menor cantidad arsenopirita, betekhtinita, bornita, matildita, oro, plata, electrum, telurio, cervelleíta y hematita. La galena presenta numerosas inclusiones de angelaíta, aikinita, wittichenita y miharaíta. Esta paragénesis se presenta en vetas asociada a diferentes rocas volcánicas de la Formación Lonco Trapial de edad jurásica. La composición química de angelaíta fue obtenida con una microsonda electrónica. Se presenta en granos anhedrales de 10-100mm, es de color gris verdoso, moderadamente pleocroica y anisótropa.Angelaíte Cu2AgPbBiS2, a new mineral species, occurs in Mina Ángela, an IS type mineralization at the Los Manantiales district. The assemblage contains sphalerite, pyrite, chalcopyrite, galena with numerous inclusions of angelaíte, aikinite, miharaíte, and in smaller amounts arsenopyrite, betekhtinite, bornite, matildite, gold, silver, electrum, tellurium cervelleíte and hematite. Galena presents numerous inclusions of angelaíta, aikinita, wittichenita y miharaíta. This paragenesis occurs in veins associated with different volcanic rocks of the jurassic Lonco Trapial Formation. Angelaíte was observed as anhedral grains of 10-100mm, greenish grey in colour, moderately pleochroic and anisotropic.

  10. 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?

    Directory of Open Access Journals (Sweden)

    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.

  11. Benthic methylmercury production in lacustrine ecosystems of Nahuel Huapi National Park, Patagonia, Argentina

    Science.gov (United States)

    Ribeiro, Guevara S.; Catan, S.P.; Marvin-DiPasquale, M.

    2009-01-01

    Seasonal trends of benthic methylmercury (methyl-Hg) production were examined in both littoral and open water sites of three lakes (Escondido, Moreno, and Morenito) in the North Andean Patagonia region of Argentina. Potentials of methyl-Hg production were measured by amending sediment samples with inorganic 197Hg(II), incubating for either 24 and 32 h at room temperature, and subsequently assaying the radiolabelled organomercury produced. Seasonal variations of benthic methyl-Hg production were studied but no significant correlation was observed. Lake littoral sites exhibited up to two fold higher methyl-Hg production potentials in most cases. Sediment from lakes Moreno and Morenito generally exhibited much lower (up to 10 fold) methyl-Hg production potentials than those from Lake Escondido, possibly due to differences in particulate and dissolved organic matter quantity and quality, which is higher in Lake Escondido and primarily allochthonous, whereas in lakes Moreno and Morenito is primarily autochthonous. This study represents the first to directly examine benthic microbial Hg(II)-methylation in aquatic ecosystems of Patagonia. ?? 2009 Elsevier Ltd. All rights reserved.

  12. A gigantic, exceptionally complete titanosaurian sauropod dinosaur from southern Patagonia, Argentina.

    Science.gov (United States)

    Lacovara, Kenneth J; Lamanna, Matthew C; Ibiricu, Lucio M; Poole, Jason C; Schroeter, Elena R; Ullmann, Paul V; Voegele, Kristyn K; Boles, Zachary M; Carter, Aja M; Fowler, Emma K; Egerton, Victoria M; Moyer, Alison E; Coughenour, Christopher L; Schein, Jason P; Harris, Jerald D; Martínez, Rubén D; Novas, Fernando E

    2014-09-04

    Titanosaurian sauropod dinosaurs were the most diverse and abundant large-bodied herbivores in the southern continents during the final 30 million years of the Mesozoic Era. Several titanosaur species are regarded as the most massive land-living animals yet discovered; nevertheless, nearly all of these giant titanosaurs are known only from very incomplete fossils, hindering a detailed understanding of their anatomy. Here we describe a new and gigantic titanosaur, Dreadnoughtus schrani, from Upper Cretaceous sediments in southern Patagonia, Argentina. Represented by approximately 70% of the postcranial skeleton, plus craniodental remains, Dreadnoughtus is the most complete giant titanosaur yet discovered, and provides new insight into the morphology and evolutionary history of these colossal animals. Furthermore, despite its estimated mass of about 59.3 metric tons, the bone histology of the Dreadnoughtus type specimen reveals that this individual was still growing at the time of death.

  13. First paleoparasitological record of acanthocephalan eggs from Northwestern Patagonia (Late Holocene, Argentina).

    Science.gov (United States)

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

    2015-06-01

    Eggs representative of an acanthocephalan were found in an ancient fragment of raptor pellet, probably belonged to the barn owl, Tyto alba, from the archeological site named "Epullán Chica cave." This site is a cave located at the southern of Neuquén Province, Patagonia, Argentina. The fragment of pellet was found in a layer with charcoals dated at 1980±80 years B.P. A total of 56 eggs were found. Eggs were brown colored and thick-shelled, and presented four membranes, the outer lightly sculpted. The embryos presented hooks in one extremity. Measurements ranged from 87.5 to 107.5μm long and 50 to 57.5μm wide. Eggs were very well-preserved, and were identified as belonged to Class Archiacanthocephala, Order Oligacanthorhynchida, Family Oligacanthorhynchidae, probably Macracanthorhynchus Travassos, 1917, or an unidentified species. This is the first report of small mammal acanthocephalans from ancient material worldwide.

  14. 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

  15. Parasites in rodent coprolites from the historical archaeological site Alero Mazquiarán, Chubut Province, Argentina

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    Norma Haydée Sardella

    2009-02-01

    Full Text Available The aim of this study was to examine the parasitic remains that were found in rodent coprolites collected from the archaeological site Alero Mazquiarán (Chubut Province, 45º44'15"S, 70°25'9"W, which is assigned to the interface of the Araucanian and Tehuelche cultures, dated at 212 ± 35 years B.P. The faecal material from two unidentified rodent species (X-10 and X-11 was collected from one human pelvic cavity found in a multiple burial. The faecal samples were processed and examined using paleoparasitological procedures. The X-10 coprolites were positive for eggs of Monoecocestus sp. (Cestoda: Anoplocephalidae and the X-11 faeces were positive for Pterygodermatites sp. (Nematoda: Rictulariidae, Trichosomoides sp. (Nematoda: Trichosomoididae and Monoecocestus sp. In this study, we discuss parasitic life cycles, the zoonotic importance of parasites and the behaviour of the aboriginal people.

  16. Parasites in rodent coprolites from the historical archaeological site Alero Mazquiarán, Chubut Province, Argentina.

    Science.gov (United States)

    Haydée Sardella, Norma; Horacio Fugassa, Martín

    2009-02-01

    The aim of this study was to examine the parasitic remains that were found in rodent coprolites collected from the archaeological site Alero Mazquiarán (Chubut Province, 45 degrees 44'15''S, 70 degrees 25'9''W), which is assigned to the interface of the Araucanian and Tehuelche cultures, dated at 212 +/- 35 years B.P. The faecal material from two unidentified rodent species (X-10 and X-11) was collected from one human pelvic cavity found in a multiple burial. The faecal samples were processed and examined using paleoparasitological procedures. The X-10 coprolites were positive for eggs of Monoecocestus sp. (Cestoda: Anoplocephalidae) and the X-11 faeces were positive for Pterygodermatites sp. (Nematoda: Rictulariidae), Trichosomoides sp. (Nematoda: Trichosomoididae) and Monoecocestus sp. In this study, we discuss parasitic life cycles, the zoonotic importance of parasites and the behaviour of the aboriginal people.

  17. Análisis de la diversidad biológica y mestizaje en la ciudad de Puerto Madryn (Prov. de Chubut, Argentina

    Directory of Open Access Journals (Sweden)

    Parolín, María Laura

    2013-12-01

    Full Text Available En el marco del estudio de la composición genética de las poblaciones cosmopolitas de Argentina, se analizó una muestra poblacional de la localidad de Puerto Madryn (PM con la finalidad de evaluar su diversidad biológica mediante la utilización de marcadores biparentales y uniparentales y comparar los resultados con los obtenidos previamente por nuestro equipo de investigación en seis poblaciones cosmopolitas de distintas regiones de la Argentina, aunque poniendo el énfasis en las correspondientes a la Región Patagónica.Las muestras biológicas fueron tomadas con consentimiento informado a 82 dadores de sangre no emparentados que concurrieron al Banco de Sangre y al Hospital Subzonal de dicha localidad, a quienes también se les realizó una encuesta genealógica. A partir de los datos proporcionados por los marcadores autosómicos, se registró una contribución europea de 67.2%, amerindia de 29.4% y africana de 3.4%. A un origen amerindio fueron adscriptos el 59.9% y 8.7% de los linajes maternos y paternos, respectivamente, revelando un desigual aporte autóctono por género.El aporte europeo se vio representado principalmente por el Hg H (19.5% y se detectaron sólo dos linajes subsaharianos.En PM las migraciones desde el centro del país han generado un fuerte impacto, reflejado en la mayor contribución de marcadores europeos respecto de dos muestras estudiadas previamente en Chubut (Comodoro Rivadavia y Esquel. Estas diferencias al interior de una misma provincia nos advierten que no puede abordarse el análisis de la constitución genética de las poblaciones sin dar cuenta de las particularidades regionales.

  18. Composición corporal de escolares pertenecientes a diferentes contextos socioeconómicos de Puerto Madryn, Chubut, Argentina

    Directory of Open Access Journals (Sweden)

    Dahinten, Silvia Lucrecia

    2007-01-01

    Full Text Available El desigual desarrollo del tejido muscular y de la distribución de tejido adiposo que tiene lugar durante el crecimiento humano presenta dimorfismo sexual (DS, en condiciones de vida saludables. Esta variación ha sido traducida en algoritmos utilizando la circunferencia y pliegues subcutáneos del brazo y se han elaborado ecuaciones para calcular áreas. El objetivo fue evaluar el DS observado en el crecimiento corporal de escolares de 6 a 14 años de hogares con diferente NBI -(NBI alto y (NBI bajo-. Se estudió transversalmente una muestra de 500 mujeres y 570 varones de la ciudad de Puerto Madryn, Chubut. Se relevaron: perímetro braquial y pliegues subcutáneos tricipital y subescapular y se calcularon las áreas adiposa (AAB y muscular (AMB. Se utilizaron pruebas de Wilcoxon, p= 0.05. El AAB de las mujeres fue a casi todas las edades superior a la de los varones (NBI bajo p=0.09; NBI alto p=0.02. A edades tempranas, el AMB mostró que los varones presentaron cifras similares a las mujeres. A partir de los 12 años, sin embargo, los varones comenzaron a incrementar la masa muscular. En las niñas este aumento se hizo mucho más lento (NBI alto p=0.01; NBI bajo p=0.03. La ausencia de DS en el NBI bajo, para los caracteres considerados, se relaciona con el aumento de tejido adiposo en los varones de este sector que muestra la adopción dentro de la comunidad, de dietas de alto contenido en grasas y carbohidratos acompañadas de altas tasas de obesidad.

  19. 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.

  20. 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.

  1. New species of dictyostelids from Patagonia and Tierra del Fuego, Argentina.

    Science.gov (United States)

    Vadell, Eduardo M; Cavender, James C; Romeralo, Maria; Edwards, Sally M; Stephenson, Steven L; Baldauf, Sandra L

    2011-01-01

    In late Jan and early Feb 2005 samples for isolation of dictyostelid cellular slime molds (dictyostelids) were collected in five different provinces and from six national parks (all located 39-55°S) in Patagonia and Tierra del Fuego, Argentina. Southern beech (Nothofagus) forests represented the primary vegetation type investigated, but some samples were obtained from Patagonian steppe, alpine meadows, Valdivian temperate rainforests and coniferous forests dominated by Araucaria, Austrocedrus and Fitzroya. Among the dictyostelids isolated from the samples we collected were seven species new to science. These species (Dictyostelium austroandinum, D. chordatum, D. fasciculoideum, D. gargantuum, D. leptosomopsis, D. valdivianum and Polysphondylium patagonicum) are described herein on the basis of both morphology and molecular (SSU rDNA) data. One of the new species, D. gargantuum, is one of the largest representatives of the group reported to date. Another unusual species, D. chordatum, produces long interwoven sorocarps that do not appear to respond to a spacing gas similar to the condition first noted in D. implicatum. PMID:20943559

  2. Iridium, platinum and rhodium baseline concentration in lichens from Tierra del Fuego (South Patagonia, Argentina).

    Science.gov (United States)

    Pino, Anna; Alimonti, Alessandro; Conti, Marcelo Enrique; Bocca, Beatrice

    2010-10-01

    Lichen samples of Usnea barbata were used as possible biomonitors of the atmospheric background level of iridium (Ir), platinum (Pt) and rhodium (Rh) in the remote region of Tierra del Fuego (South Patagonia, Argentina). Lichens were collected in 2006 at 53 sites covering 7 different areas of the region (24 transplanted lichens of the northern region and 29 native lichen samples of the central-southern region). A microwave acidic digestion procedure was used to mineralize the samples and a sector field inductively coupled plasma mass spectrometry method was developed to quantify the elements. The study of the influence of interferences on analyte signals and a quality control procedure were carried out. The analytical protocol was further applied to evaluate Ir, Pt and Rh bioaccumulation in lichens. The detection limits obtained were 0.010 ng g⁻¹, 0.013 ng g⁻¹ and 0.030 ng g⁻¹ for Ir, Pt and Rh, respectively. Recoveries at different fortification levels were between 96.3% and 106% and precision was 3.3% on average. The metals concentration (as dry weight) spanned the following ranges: Ir, Tierra del Fuego. Values detected are more likely influenced by the long-range atmospheric transport of these pollutants and, in comparison with densely populated areas in the world, they can represent the baseline for low impacted areas. PMID:20830409

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

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    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.

  4. MAMÍFEROS INVASORES EN LA PATAGONIA ARGENTINA: EL CONEJO SILVESTRE EUROPEO COMO CASO EMBLEMÁTICO

    OpenAIRE

    Never Antonio Bonino Vassallo

    2010-01-01

    Se brinda una reseña de los estudios biológicos y ecológicos realizados sobre el conejo silvestre europeo (Oryctolagus cuniculus), tal vez el más emblemático de los mamíferos exóticos introducidos en Argentina. En el sector continental argentino el conejo se encuentra establecido, y en proceso de dispersión, principalmente en las provincias de Mendoza y Neuquén (NO de la Patagonia). En esta región, el conejo ha demostrado tener un efecto negativo sobre la economía regional, especialmente e...

  5. Allocreadium pichi n. sp. (Trematoda: Allocreadiidae) in Galaxias maculatus (Osteichthyes: Galaxiidae) from Lake Moreno in Patagonia (Argentina).

    Science.gov (United States)

    Flores, Verónica R; Brugni, Norma; Ostrowski de Núñez, Margarita

    2004-07-01

    Allocreadium pichi n. sp. (Trematoda: Allocreadiidae) is described from the intestine of Galaxias maculatus (Osteichthyes: Galaxiidae) from Moreno Lake in Patagonia, Argentina. This species is distinguished from A. patagonicum Shimazu, Urawa & Coria, 2000, the other species recorded in the area, by its smaller body size, the diagonal position of the testes and different ratios of the suckers, testes and cirrus-sac in relation to body size. In addition, the synonymy of A. patagonicum with Polylekithum percai Ostrowski de Núñez, Brugni & Viozzi, 2000 is proposed herein. PMID:15218369

  6. Abundance estimates of southern right whales (Eubalaena australis) in Bahía San Antonio, Patagonia, Argentina

    OpenAIRE

    Vermeulen, Els; Cammareri, Alejandro

    2012-01-01

    Aerial surveys were conducted to estimate the abundance of southern right whales in Bahía San Antonio, a bay located in the north-western region of the San Matías Gulf (40°50¿S 64°50¿W), Rio Negro, Patagonia Argentina. The transect for the realization of aerial surveys was designed using the program DISTANCE 6.0 and consisted out of 14 North-South (up to S 40.9°) parallel transect lines with a 2.5km separation, covering a total surface of 418km² (mean coverage probability=0.78). Transect leng...

  7. Patagonian and Antarctic dust as recorded in the sediments of Laguna Potrok Aike (Patagonia, Argentina)

    Science.gov (United States)

    Haberzettl, Torsten; Stopp, Annemarie; Lisé-Pronovost, Agathe; Gebhardt, Catalina; Ohlendorf, Christian; Zolitschka, Bernd; von Eynatten, Hilmar; Kleinhanns, Ilka; Pasado Science Team

    2010-05-01

    Although an increasing number of terrestrial paleoclimatic records from southern South America has been published during the last decade, these archives mostly cover the Lateglacial and/or the Holocene. Only little is known about the Patagonian climate before the Last Glacial Maximum. Here, we present a continuous, high-resolution magnetic susceptibility record for the past 48 ka from the maar lake Laguna Potrok Aike (51°58' S, 70°23' W, southern Patagonia, Argentina). Magnetic susceptibility serves as an excellent parameter for the parallelization of sediment cores all over Laguna Potrok Aike including sediment cores taken within the ICDP (International Continental Scientific Drilling Program) project PASADO (Potrok Aike maar lake Sediment Archive Drilling prOject). Additionally, magnetic susceptibility is assumed to be a proxy for dust deposition in this lake. Distinct similarities were found between the independently dated magnetic susceptibility record from Laguna Potrok Aike and the non-sea-salt calcium (nss-Ca) flux from the EPICA Dome C ice core record (75°06'S, 123°24'E) the latter being a proxy for mineral dust deposition in Antarctica [1]. Comparison of the two records and variations in grain size of the Laguna Potrok Aike sediment records indicate a relatively high aeolian activity in southern South America during the glacial period. During the Holocene climatic conditions driving sediment deposition seem to have been more variable and less dominated by wind compared to glacial times. Although the source of the dust found in Antarctic ice cores often has been attributed to Patagonia [2], we present the first evidence for contemporaneity of aeolian deposition in both the target area (Antarctica) and the major source area (Patagonia). Considering the similarities of the two records, magnetic susceptibility might yield the potential for chronological information: transfer of the ice core age model to a lacustrine sediment record. This would be important

  8. 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

  9. 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

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

    Directory of Open Access Journals (Sweden)

    Sebastián Apesteguía

    Full Text Available 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.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.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.

  11. 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. PMID:26091542

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

    Directory of Open Access Journals (Sweden)

    Guillermo Martín Svendsen

    Full Text Available 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.

  13. 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)

  14. Parasitological findings of lesser rhea, Pterocnemia pennata (D´ ORBIGNY in faeces FROM NORTHERN PATAGONIA, ARGENTINA Hallazgos parasitológicos en deposiciones de Lesser Rhea, Pterocnemia Pennata (D'orgiby, del norte de la patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    E. Chang Reissig

    2001-01-01

    Full Text Available La información acerca de parásitos que afectan a la producción de choiques criados en granjas en Argentina es escasa. El objetivo de este estudio fue determinar la prevalencia de enfermedades parasitarias en granjas de choiques. Durante un año se realizaron muestreos periódicos en 10 granjas de choiques (Pterocnemia pennata localizadas en el norte de la Patagonia Argentina. Un total de 310 muestras de materia fecal fresca de pichones, juveniles y adultos fueron recolectadas y analizadas por las técnicas de Willis y McMaster. De 310 muestras de material fecal analizadas, 31.3% de las muestras presentaron ooquistes de Eimeria spp, 1.9% huevos de Capillaria sp y 8.7% huevos de Trichostrongylus sp. Los recuentos de huevos y ooquistes por gramo de materia fecal resultaron bajos en la mayoría de los análisis. Se registró infección por Capillaria sp (Nematoda en 32% de las aves de una granja. De acuerdo a nuestros resultados, las infecciones parasitarias en choiques no constituirían un grave problema en los sistemas productivos de Argentina. Este es el primer estudio realizado en Argentina que reporta el nivel de parasitismo en choiques criados en granjas

  15. 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

  16. Ozone and Temperature Lidar observations in mid-latitude NDACC station at Río Gallegos (51°36‘ S, 69° 19‘ W), Patagonia Argentina

    OpenAIRE

    2013-01-01

    The CEILAP Lidar group joined with Japanese and French researchers, with the financial support from Japan International Cooperation Agency (JICA) has carried out a modern observational site at southern America. The Atmospheric Observatory of Austral Patagonia (OAPA) is a remote sensing site located near the Río Gallegos city in South Patagonia-Argentina (51º 55’S, 69º 14’W), in subpolar region affected by the polar vortex. It is a convenient monitoring site of the atmosphere in the southern h...

  17. El patrimonio industrial petrolero en la Patagonia: Comodoro Rivadavia (Argentina y Cerro Sombrero (Chile. Una perspectiva comparada

    Directory of Open Access Journals (Sweden)

    Pía Acevedo Méndez

    2016-01-01

    Full Text Available El hallazgo de petróleo en Comodoro Rivadavia (Chubut, Argentina y en Manantiales (Tierra del Fuego, lado chileno, motivó la construcción de espacios socioproductivos bajo el modelo de Company Towns. En el caso argentino la empresa estatal Yacimientos Petrolíferos Fiscales (Y.P.F creó el Campamento Central y la Empresa Nacional del Petróleo (ENAP creó Cerro Sombrero en Chile, los que en la década de 1970 formaron dos tejidos urbanos (barrio en el caso argentino y pueblo en el caso chileno. En esta dinámica se transformó el modo de habitar de ambos espacios, que se convirtieron en potenciales elementos turísticos, teniendo en cuenta que desde el año 2014 poseen reconocimiento patrimonial relacionado con su pasado petrolero y su arquitectura moderna. El objetivo es comparar cómo ambas empresas petroleras estatales construyeron dichos espacios “urbanos” y sus comunidades sociolaborales e indagar en la relación identidad/ patrimonio de ypefeanos y enapinos.

  18. Geophysical characterization of two circular structures at Bajada del Diablo (Patagonia, Argentina): Indication of impact origin

    Science.gov (United States)

    Prezzi, Claudia B.; Orgeira, María Julia; Acevedo, Rogelio D.; Ponce, Juan Federico; Martinez, Oscar; Rabassa, Jorge O.; Corbella, Hugo; Vásquez, Carlos; González-Guillot, Mauricio; Subías, Ignacio

    2012-02-01

    An impact origin has been proposed for the circular structures found in Bajada del Diablo, Patagonia, Argentina. Taking into account its extension and the number of impact structures, Bajada del Diablo would be the largest meteoritic impact areas known on Earth, being an extremely interesting area for the research of impact events and processes. Moreover, the global distribution of known impact structures shows a surprising asymmetry. Particularly, South America has only seven described areas. It is evident that this situation is an artifact, highlighting the importance of intensifying the research in the least studied areas such as Argentina. Circular structures in Bajada del Diablo have been identified on two rock types: the Quiñelaf eruptive complex and Pampa Sastre Formation. In the first case, circular structures are placed in olivine basalts. On the other hand, Pampa Sastre Formation (late Pliocene/early Pleistocene) corresponds to conglomerate layers with basalt clasts boulder and block in size in a coarse sandy matrix. With the aim of further the investigation of the proposed impact origin for these circular structures, we carried out detailed topographic, magnetic and electromagnetic ground surveys in two circular structures ("8" and "A") found in Pampa Sastre conglomerates. Both circular structures are simple, bowl-shaped with rim diameters of 300 m and maximum depths of 10 m. They have been partially filled in by debris flows from the rims and wind-blown sands. Two preliminary magnetic profiles have also been carried out in circular structure "G" found in Quiñelaf basalts. The magnetic anomalies show a circular pattern with a slightly negative and relatively flat signal in the circular structures' bases. Furthermore in the circular structures' rims, high-amplitude, conspicuous and localized (short wavelength) anomalies are observed. Such large amplitude and short wavelength anomalies are not detected outside the circular structures. For all used

  19. Revision of Plumarius Philippi 1873 (Hymenoptera: Chrysidoidea, Plumariidae) from Argentina north of Patagonia, with description of eighteen new species.

    Science.gov (United States)

    Diez, Patricia A; Roig-Alsina, Arturo

    2016-01-01

    Twenty six species of Plumarius from Argentina north of Patagonia are revised. Eighteen new species: Plumarius politus sp. nov., P. sarophorus sp. nov., P. globulosus sp. nov., P. angulatus sp. nov., P. noa sp. nov., P. divergens sp. nov., P. malaris sp. nov., P. gracilior sp. nov., P. riojanus sp. nov., P. exophthalmus sp. nov., P. planatus sp. nov., P. albinervis sp. nov., P. truncatus sp. nov., P. mikrommatus sp. nov., P. obscurus sp. nov., P. gracilis sp. nov., P. fidalgoi sp. nov., and P. ocellulatus sp. nov. are described and illustrated. A new record for known species as well as a key to 26 known species in the region is given. A redescription of P. tumidulus Papp, 2000, which is the first record of the family Plumariidae from Uruguay, is done. PMID:27394595

  20. Temperature and foliage quality affect performance of the outbreak defoliator Ormiscodes amphimone (F.) (Lepidoptera: Saturniidae) in northwestern Patagonia, Argentina La temperatura y la calidad del follaje afectan el desempeño del defoliador epidémico Ormiscodes amphimone (F.) (Lepidoptera: Saturniidae) en el noroeste de la Patagonia argentina

    OpenAIRE

    JUAN PARITSIS; Veblen, Thomas T

    2010-01-01

    In the temperate forests of Chile and Argentina the phytophagous moth Ormiscodes amphimone (F.) causes severe defoliation on the southern beech tree Nothofagus pumilio (Poepp. & Endl.) Krasser. The recent increase in defoliation frequency in some áreas appears to be influenced by a warmer climate. To evalúate the effects of temperature and the spatial heterogeneity of foliage quality on the performance and relative consumption rate of O. amphimone in northwestern Patagonia, Argentina we condu...

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Presencia de una nueva avispa social exótica, Polistes dominulus (Hymenoptera: Vespidae en la Patagonia argentina Presence of a new exotic social wasp in Patagonia, Argentina

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    Paula Sackmann

    2003-07-01

    Full Text Available La presencia de la avispa social Polistes dominulus (Christ (Hymenoptera: Vespidae fue detectada en el jardkn de una vivienda de la localidad de El Bolsón (Rko Negro, siendo el primer registro para la Argentina. Esta especie de origen Paleirtico, se encuentra establecida en Chile desde hace 20 años.We report the presence of the social wasp Polistes dominulus (Christ (Hymenoptera: Vespidae in El Bolsón (Rko Negro. This is the first record of the species in Argentina. All specimens were found in a garden within an urban area. The species is of Paleartic origin, but has been established in Chile for at least 20 years.

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

    OpenAIRE

    Monserrat, V. J.; Freitas, S

    2005-01-01

    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 Ch...

  4. An apparent outbreak of cutaneous papillomatosis in merino sheep in patagonia, Argentina.

    Science.gov (United States)

    Uzal, F A; Latorraca, A; Ghoddusi, M; Horn, M; Adamson, M; Kelly, W R; Schenkel, R

    2000-04-01

    A retrospective study was performed on skin samples from an outbreak of cutaneous papillomatosis in Merino sheep that occurred in 1995. The samples were processed for routine histology, electron microscopy and immunocytochemistry for papilloma viruses. Particles of approximately 55 nm diameter were found in some nuclei of the stratum granulosum cells, while immunocytochemistry gave positive staining of cell nuclei in this layer. This study confirms that papillomas associated with papillomaviruses occur in sheep in Patagonia. PMID:10836278

  5. Multi-century tree-ring based reconstruction of the Neuquén River streamflow, northern Patagonia, Argentina

    Science.gov (United States)

    Mundo, I. A.; Masiokas, M. H.; Villalba, R.; Morales, M. S.; Neukom, R.; Le Quesne, C.; Urrutia, R. B.; Lara, A.

    2012-04-01

    In most cases, gauged river flow records in southern South America extend for only a few decades, hampering the detection of long-term, decadal to centennial-scale cycles and trends. Long streamflow series can be reconstructed from tree-ring records, offering the opportunity of extending the limited hydrological instrumental data to several centuries. In northern Patagonia, Argentina, the Neuquén River has great importance for local and national socio-economic activities such as hydroelectric power generation, agriculture and tourism. In this study, new and updated tree-ring chronologies from Araucaria araucana and Austrocedrus chilensis are used to reconstruct the October-June mean streamflow for the Neuquén River and place the period of gauged flows (1903-2009), in a long-term, multi-century context. The reconstruction covers the period 1346-2000 AD and was developed from a network of 43 tree-ring chronologies, grouped in composite series, using a nested principal component regression approach. Analyses of the frequency, intensity, and duration of droughts and pluvial events indicate that the 20th century contains some of the driest and wettest annual to decadal-scale events in the last 654 yr, but longer and more severe events were recorded in previous centuries. Blackman-Tukey and singular spectral analyses identified quasiperiodic oscillations from 3.5 to 17.5 yr. A dominant 6.8-yr cycle explains ca. 23.6% of the total variance in the Neuquén River streamflow reconstruction. Correlation analyses showed that discharges of the Neuquén River are related to variations in the Southern Annular Mode (SAM), a measure of air mass exchanges between middle and high latitudes in the Southern Hemisphere. This association is consistent with previous studies that indicate a strong correlation between rainfall in northern Patagonia and SAM variations.

  6. 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

  7. Multi-century tree-ring based reconstruction of the Neuquén River streamflow, northern Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    I. A. Mundo

    2011-10-01

    Full Text Available In most cases, gauged river flow records in southern South America exist for only a few decades, hampering the detection of long-term, decadal to centennial-scale cycles and trends. Long streamflow series can be reconstructed from tree-ring records, offering the opportunity of extending the limited hydrological instrumental data for several centuries or millennia. In northern Patagonia, Argentina, the Neuquén River has great importance for local and national socio-economic activities such as hydroelectric power generation, agriculture and tourism. In this study, new and updated tree-ring chronologies from Araucaria araucana and Austrocedrus chilensis are used to reconstruct the October–June mean streamflow for the Neuquén River and place the period of gauged flows, 1903–2009, in a long-term, multi-century context. The reconstruction covers the period 1346–2000 AD and was developed through a nested principal components regression approach using a network of 43 tree-ring chronologies grouped in composite series. Analyses of the frequency, intensity, and duration of droughts and pluvial events indicate that the 20th century contains some of the driest and wettest annual to decadal-scale events in the past millennium, but longer and more severe events can also be observed in previous centuries. Blackman-Tukey and Singular Spectral Analyses identified various multi-decadal quasiperiodic oscillations with a dominant 6.8-year cycle explaining ca. 23.6% of the total variance in the Neuquén River streamflow reconstruction. We also found that the Neuquén River discharges are related to variations in the Southern Annular Mode (SAM, a measure of air mass exchanges between middle and high latitudes in the Southern Hemisphere. This association is consistent with previous studies which indicate a strong connection between rainfall patterns in northern Patagonia and SAM activity.

  8. Multi-century tree-ring based reconstruction of the Neuquén River streamflow, northern Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    I. A. Mundo

    2012-04-01

    Full Text Available In most cases, gauged river flow records in southern South America extend for only a few decades, hampering the detection of long-term, decadal to centennial-scale cycles and trends. Long streamflow series can be reconstructed from tree-ring records, offering the opportunity of extending the limited hydrological instrumental data to several centuries. In northern Patagonia, Argentina, the Neuquén River has great importance for local and national socio-economic activities such as hydroelectric power generation, agriculture and tourism. In this study, new and updated tree-ring chronologies from Araucaria araucana and Austrocedrus chilensis are used to reconstruct the October–June mean streamflow for the Neuquén River and place the period of gauged flows (1903–2009, in a long-term, multi-century context. The reconstruction covers the period 1346–2000 AD and was developed from a network of 43 tree-ring chronologies, grouped in composite series, using a nested principal component regression approach. Analyses of the frequency, intensity, and duration of droughts and pluvial events indicate that the 20th century contains some of the driest and wettest annual to decadal-scale events in the last 654 yr, but longer and more severe events were recorded in previous centuries. Blackman-Tukey and singular spectral analyses identified quasiperiodic oscillations from 3.5 to 17.5 yr. A dominant 6.8-yr cycle explains ca. 23.6% of the total variance in the Neuquén River streamflow reconstruction. Correlation analyses showed that discharges of the Neuquén River are related to variations in the Southern Annular Mode (SAM, a measure of air mass exchanges between middle and high latitudes in the Southern Hemisphere. This association is consistent with previous studies that indicate a strong correlation between rainfall in northern Patagonia and SAM variations.

  9. 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

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    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

  10. Movilidad Espacial, Ocupación y Empleo en el Valle Inferior del Río Chubut Spatial mobility, Occupation and Employment in the Inferior Valley of the River Chubut

    Directory of Open Access Journals (Sweden)

    M. Marcela Crovetto

    2011-12-01

    Full Text Available Desde una perspectiva que propone una serie de críticas a la tipología dicotómica de clasificación demográfica del espacio habitado, rural y urbano, se ha indagado sobre las formas que adquiere la movilidad espacial cotidiana en relación al empleo y a la ocupación en el Valle Inferior del Río Chubut -patagonia argentina-, atendiendo a una situación especial de movilidad espacial cotidiana como es la referida a la producción de cerezas en el Valle. Se utilizaron fuentes secundarias estadísticas, históricas y documentales en articulación con la construcción de datos primarios mediante relevamientos operados por distintas técnicas. Fundamentalmente se aplicó una encuesta a hogares (200 casos de barrios periféricos de las localidades involucradas en el Valle Inferior del Río Chubut El centro del ejercicio de la investigación estuvo en contraponer los resultados de una encuesta realizada en campo de acuerdo tanto a la clasificación clásica de la zona de residencia (rural o urbana como a una propuesta alternativa para la investigación. Así se evaluaron los matices escondidos dentro de las homogeneizantes ideas de rural y urbano, sintetizadas por la cantidad de habitantes -en Argentina con 2000 o más se considera un espacio urbano, con menos un espacio rural- observándose, especialmente, que muchas trayectorias cotidianas de actores sociales considerados clásicamente urbanos se acercaban mucho a las de los actores de las zonas rurales.From a perspective that proposes a number of criticisms of the dichotomous typology of demographic classification of living space, rural and urban, has inquired about the forms that everyday spatial mobility in relation to employment in the Valle Inferior del Río Chubut - Patagonia-Argentina, following a special situation of everyday spatial mobility as that concerning the production of cherries in the Valley. Were used statistics, historical and documentary in coordination with the construction

  11. 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

  12. 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.

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

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    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.

  14. Life-cycle stages of a Posthodiplostomum species (Digenea: Diplostomidae) from Patagonia, Argentina.

    Science.gov (United States)

    Ritossa, Luciano; Flores, Verónica; Viozzi, Gustavo

    2013-10-01

    In Patagonia, populations of the galaxiid fish Galaxias maculatus are parasitized by metacercariae of a species of Posthodiplostomum (Digenea: Diplostomidae). The aim of this work was to describe larval and adult stages of this species in experimental and natural hosts from an Andean Patagonian lake. Specimens of G. maculatus and the pulmonate snail, Anisancylus obliquus, were collected in Patagua Lake. The snails were isolated in individual containers to observe emergence of cercariae, dissected, and examined under a stereoscopic microscope to record sporocysts and cercariae. Fish were examined to obtain metacercariae, and uninfected fish from Gutiérrez Lake were exposed to cercariae from A. obliquus to obtain experimental metacercariae. Chicks and mice were infected with metacercariae from naturally infected G. maculatus to obtain experimental adults. Specimens recovered belong to Posthodiplostomum sp. on the basis of morphological features. This is the first description of sporocysts, cercariae, metacercariae, and adults stages of a Posthodiplostomum species in Patagonia, including data about its natural intermediate hosts. PMID:23628085

  15. Modeling volcanic ash resuspension – application to the 14–18 October 2011 outbreak episode in Central Patagonia, Argentina

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    A. Folch

    2013-09-01

    Full Text Available Volcanic fallout deposits from the June 2011 Cordón Caulle eruption in Central Patagonia were remobilized in several occasions months after their emplacement. In particular, during 14–18 October 2011, an intense outbreak episode generated huge volcanic clouds that were dispersed across Argentina, causing multiple impacts in the environment, affecting the air quality and disrupting airports. Fine ash particles in volcanic fallout deposits can be resuspended under favourable meteorological conditions, particularly during strong wind episodes in arid environments having low soil moisture and poor vegetation coverage. In opposition to eruption-formed ash clouds, modeling of resuspension-formed ash clouds has received little attention. In consequence, there are no emission schemes specially developed and calibrated for volcanic ash, and no operational product exists to model and forecast the formation and dispersal of resuspension ash clouds. Here we implement three dust emission schemes of increasing complexity in the FALL3D tephra dispersal model and use the 14–18 October 2011 outbreak episode as a model test case. We calibrate the emission schemes and validate the results of the coupled WRF-ARW/FALL3D modeling system using satellite imagery and measurements of visibility (a quantity related to total suspended particle concentration at surface and particulate matter (PM10 concentration at several meteorological and air quality stations sparse across Argentina and Uruguay. Our final goal is to test the capability of the modeling system to become, in the near future, an operational forecast product for volcanic ash resuspension events.

  16. 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.

  17. PRIMEROS POBLADORES ESPAÑOLES EN EL FUERTE-POBLADO DE EL CARMEN, PATAGONIA ARGENTINA (FINALES DEL SIGLO XVIII

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    María Laura Casanueva

    2009-12-01

    Full Text Available In this work we present our current historic- anthropologic investigation aboutthe first Spanish settlers installed on the end of 18th century in Fuerte de El Carmen town (Buenos Aires province, Argentina. The objective to colonize this territory was toconsolidate Spanish possessions in the South Atlantic, threatened by constant foreigner presence. This is how Spanish people arrived from different regions, attracted by promises of lands, work and inhabitation. Nevertheless, once arrived, authorities did not complywith those promises and families had to build their houses digging caves in the Rio Negroscarps, known today as Maragatos caves.Nowdays, our work is focused on those first homes and face to the main objective of the project, which is to: access to the knowledge of the historic change processes,the restructuration and continuity of those populations of creole-european origin, and to study their link with aboriginal inhabitants during XVIIIth and XIXth centuries in thePampa-Patagonia region. Besides, our objective is to investigate the maragato’s popular origin myth of these home-caves dig in the north cliff of Rio Negro.

  18. MAMÍFEROS INVASORES EN LA PATAGONIA ARGENTINA: EL CONEJO SILVESTRE EUROPEO COMO CASO EMBLEMÁTICO

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    Never Antonio Bonino Vassallo

    2010-04-01

    Full Text Available Se brinda una reseña de los estudios biológicos y ecológicos realizados sobre el conejo silvestre europeo (Oryctolagus cuniculus, tal vez el más emblemático de los mamíferos exóticos introducidos en Argentina. En el sector continental argentino el conejo se encuentra establecido, y en proceso de dispersión, principalmente en las provincias de Mendoza y Neuquén (NO de la Patagonia. En esta región, el conejo ha demostrado tener un efecto negativo sobre la economía regional, especialmente en áreas ganaderas y en plantaciones comerciales de árboles frutales y maderables. No existen programas oficiales para controlar la dispersión geográfica y/o el impacto de esta especie exótica. La gente que se siente perjudicada por el conejo recurre a intentos individuales para controlar sus efectos negativos. Es necesario implementar monitoreos regulares de la dispersión del conejo para la detección temprana y el manejo de poblaciones recién establecidas; además, se requieren estudios comparativos tendientes a determinar los métodos más adecuados para controlar el impacto del conejo.

  19. A new genus of Cystidicolid nematode from the stomach of Galaxias maculatus (Osmeriformes: Galaxiidae) in Patagonia (Argentina).

    Science.gov (United States)

    Brugni, Norma L; Viozzi, Gustavo P; Fernández, María V; Vega, Rocío M

    2009-02-01

    During a parasitological survey of Galaxias maculatus (Jenyns) from Patagonian Andean Lakes, specimens of a new species of nematode were collected from the stomach of fish and studied by light and scanning electron microscopy. This species is described as the only member of a newly proposed genus of Cystidicolidae by having oral opening dorsoventrally elongated, 2 lateral pseudolabia, 4 cephalic papillae, stoma (vestibule) elongated, esophagus divided into anterior muscular and posterior glandular sections, and caudal alae in males. Placonema n. gen. (Habronematoidea, Cystidicolidae) is characterized by the combination of the following features: oral opening dorsoventrally elongated demarcated by 4 sclerotized plates and 2 well-developed pseudolabia projected to the buccal cavity, each pseudolabium with conspicuous, conical, anterior protuberances. Four cephalic papillae and deirids simple. Male with caudal alae, area rugosa absent, 4 pairs of preanal papillae, unpaired papilla present on anterior cloacal lip, and 6 pairs of postanal papillae. Larvigerous eggs without filaments. Placonema pataguense n. gen. n. sp. infects the stomach of G. maculatus from Lake Patagua (Patagonia, Argentina) and is the first species of Cystidicolidae described from G. maculatus. PMID:18652524

  20. Population structure of the snail Buccinanops globulosum (Prosobranchia, Nassariidae) in San Matías Gulf, Patagonia Argentina: Isolated enclaves?

    Science.gov (United States)

    Narvarte, Maite; Willers, Valeria; Avaca, María Soledad; Echave, María Eugenia

    2008-10-01

    In San Matías Gulf (Patagonia, Argentina), Buccinanops globulosum is typically distributed in two different areas: the intertidal-subtidal zone of Playa Villarino, where conch length reaches up to 60 mm, and the inner channel of San Antonio Bay, where individuals are not larger than 30 mm. It is suggested that both populations of B. globulosum constitute independent enclaves adapted to the local conditions and with a different population structure. This comparative study focuses on the population structure, sex ratios, growth, and size at maturity at the two sites. The data collected reveal that the individuals in San Antonio ranged from 5 to 29 mm whereas those in Villarino ranged from 4 to 61 mm. It was also observed that in San Antonio Bay, generally males outnumbered females whereas exactly the opposite occurred in Villarino. In addition, females were larger and showed a faster growth than males in both study areas. The number of egg capsules on each female ranged from 8 to 25 in San Antonio Bay and from 5 to 66 in Villarino. Size at maturity of females in San Antonio Bay was estimated at 14.47 mm and maximum estimated length at 6 years old was 33 mm. The same parameters in the individuals from Villarino were 45 and 65 mm, respectively. The comparative analysis of the above-mentioned features poses the question of whether these two populations represent either different species or different forms of the same species.

  1. 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

  2. Myxidium biliare sp. n. (Myxozoa) from gall bladder of Galaxias maculatus (Osmeriformes: Galaxiidae) in Patagonia (Argentina).

    Science.gov (United States)

    Viozzi, Gustavo P; Flores, Verónica R

    2003-09-01

    Myxidium biliare sp. n., a new myxosporean species parasitizing the gall bladder of Galaxias maculatus (Jenyns), in Patagonia, is described. Its coelozoic plasmodia were floating free in the bile. Spores are fusiform 13.7 +/- 0.9 microm long and 6.9 +/- 0.6 microm wide, with rounded ends in frontal view and slightly pointed ends in sutural view; shell with ridges and sinuous sutural line. Both maximum prevalence and maximum percentage of immature plasmodia occurred in summer. In winter the prevalence and the percentage of immature plasmodia fell to their lowest values. Prevalence was independent of host sex but increased with host length. Prevalence in 15 Patagonian Andean lakes (situated from 39 degrees 25'S to 41 degrees 30'S) ranged between 4.2% and 70%. PMID:14535344

  3. Seasonal Variation in Abundance and Time-Budget of Bottlenose Dolphins (Tursiops truncatus) in Bahía San Antonio, Patagonia, Argentina

    OpenAIRE

    Vermeulen, Els; Cammareri, Alejandro; Holsbeek, Ludo; Das, Krishna

    2012-01-01

    The abundance and time-budget of bottlenose dolphins (Tursiops truncatus) was assessed in Bahía San Antonio, Patagonia (Argentina) in the years 2009 and 2010. A total of 366.4 boat-based survey hours resulted in 64 contact hours with a total of 88 dolphin groups. Mark-recapture abundance estimations, based on 63 identified dolphins, resulted in a corrected maximum estimate of 97 and 83 individuals during winter, and a minimum of 34 and 38 individuals during autumn of 2009 and 2010 respectivel...

  4. A photo-identification catalogue of bottlenose dolphins (Tursiops truncatus) in Northeast Patagonia, Argentina: A tool for the conservation of the species

    OpenAIRE

    Vermeulen, Els; Cammareri, Alejandro; Failla, Mauricio

    2008-01-01

    A photo-identification study of bottlenose dolphins (Tursiops truncatus) was performed in the northern Gulf of San Matías, Patagonia Argentina, during the period 2006-2008. In total, 199 surveys were conducted with an average observation effort of 4.2h (SD=1.5) per survey. These surveys resulted in a total observation effort of 824.7h of which 105.7h was spend with 158 dolphin groups. Over 12,500 pictures were analysed using the automatic identification systems FinEx and FinMatch ...

  5. Abundance estimates of southern right whales (Eubalaena australis) in Bahía San Antonio, Patagonia, Argentina

    OpenAIRE

    Vermeulen, E

    2013-01-01

    The abundance of southern right whales (Eubalaena australis) was estimated by the means of aerial line-transect surveys for the area of Bahía San Antonio, a bay located in the north-western region of the San Matías Gulf (40°50’S 64°50’W), Rio Negro, Patagonia Argentina. In total, seven aerial surveys were conducted in the first week of August and September 2009, September, October and November 2010, and August, September 2011. Survey effort equalled a total flight time of 12.4h, during which ...

  6. 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.

  7. Origin of the DUPAL anomaly in mantle xenoliths of Patagonia (Argentina) and geodynamic consequences

    Science.gov (United States)

    Mazzucchelli, Maurizio; Cipriani, Anna; Hémond, Christophe; Zanetti, Alberto; Bertotto, Gustavo Walter; Cingolani, Carlos Alberto

    2016-04-01

    The sub-continental lithospheric mantle of South America has been known for some time to carry the DUPAL isotope anomaly as seen in volcanics from the Paraná volcanic province. However, this has not allowed discriminating whether the DUPAL anomaly is a primary feature of the mantle source or acquired during the upwelling and emplacement of the primary magmas. We discovered mantle xenoliths from the Tres Lagos location in Patagonia that carry evidence of percolation by metasomatic melts that imparted the DUPAL isotope anomaly signature. We discuss a model that requires four isotope components (LCC, EM2, HIMU and DM) to account for the Sr, Nd and Pb isotope variability of our samples. We propose that upwelling of hot astenosphere during the Miocene could have triggered the melting of the LCC and EM2 components carrying the DUPAL anomaly, previously entrained in the subcontinental mantle by subduction. These ascending melts would have then metasomatised the local SCLM characterised by DMM and HIMU geochemical affinity generating the hybrid DUPAL-bearing mantle sampled by the Tres Lagos xenoliths.

  8. Atmospheric background trace elements deposition in Tierra del Fuego region (Patagonia, Argentina), using transplanted Usnea barbata lichens.

    Science.gov (United States)

    Conti, Marcelo Enrique; Finoia, Maria Grazia; Bocca, Beatrice; Mele, Giustino; Alimonti, Alessandro; Pino, Anna

    2012-01-01

    Lichen, Usnea barbata, transplants taken from Tierra del Fuego (south Patagonia, Argentina) were tested as potential biomonitors of atmospheric airborne deposition in an apparently pristine environment. In 2005, lichens were sampled in a reference site (n = 31) and transplanted in the northern Region of Tierra del Fuego. After, respectively, 1 month and 1 year of exposure, we collected them. The aim of the study was to determine the bioaccumulation of 26 elements in order to evaluate the background levels in the selected area. Samples were analyzed by the sector field inductively coupled plasma mass spectrometry. Discriminant analysis on principal component analysis factors was applied in order to explore the relationship among the different elements as far as time and spatial variation in transplants regards. The analysis was tested by Monte Carlo test based on 999 replicates. The most important contamination source resulted to be the atmospheric soil particle deposition. Furthermore, the results were compared with those obtained from the lichens collected in central and southern Tierra del Fuego. This study confirms the ability of U. barbata to reflect the background levels of the 26 elements in that environment. Compared with other background sites in the world, we did confirm that Tierra del Fuego lichens have a low content of the studied elements. Tierra del Fuego turned out not to be a pristine environment as supposed, but it can be considered as a reference basal ecosystem for useful comparisons among different geographical areas. These findings can be very relevant and useful for environmental conservation programs. PMID:21409357

  9. Bajada de rahue, province of neuquen, Argentina: an interstadial deposit in northern Patagonia

    Science.gov (United States)

    Markgraf, Vera; Bradbury, J.P.; Fernandez, J.

    1986-01-01

    Pollen and diatom analyses of a radiocarbon dated lacustrine section in the temperate Andean region of Argentina (Rahue, Province Neuquen) suggest interglacial type climatic conditions between 27,000 and 33,000 yr B.P., with environments that resemble the modern conditions at the locality. This finding correlates with a woodland record from central Chile, interpreted as reflecting conditions substantially warmer and drier prior to 27,000 yr B.P. than during the following full-glacial period. It also appears to relate to the global paleoclimatic scheme derived from deep-sea records, suggesting interhemispheric synchroneity of such broad-scale palaeoclimatic phases. ?? 1986.

  10. Análisis de la diversidad biológica y mestizaje en la ciudad de Puerto Madryn (Prov. de Chubut, Argentina)

    OpenAIRE

    Parolín, María Laura; Avena, Sergio Alejandro; Fleischer, Silvina; Pretell, Mariana; Di Fabio Rocca, Francisco; Rodríguez, Debora A.; Dejean, Cristina Beatriz; Postillone, María Bárbara; Dahinten, Silvia Lucrecia; Manera, Guillermo; Carnese, Francisco R.; Vaccaro, María S.

    2013-01-01

    En el marco del estudio de la composición genética de las poblaciones cosmopolitas de Argentina, se analizó una muestra poblacional de la localidad de Puerto Madryn (PM) con la finalidad de evaluar su diversidad biológica mediante la utilización de marcadores biparentales y uniparentales y comparar los resultados con los obtenidos previamente por nuestro equipo de investigación en seis poblaciones cosmopolitas de distintas regiones de la Argentina, aunque poniendo el énfasis en las correspond...

  11. 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.

  12. 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.

  13. Analysis of admixture and genetic structure of two Native American groups of Southern Argentinean Patagonia.

    Science.gov (United States)

    Sala, Andrea; Corach, Daniel

    2014-03-01

    Argentinean Patagonia is inhabited by people that live principally in urban areas and by small isolated groups of individuals that belong to indigenous aboriginal groups; this territory exhibits the lowest population density of the country. Mapuche and Tehuelche (Mapudungun linguistic branch), are the only extant Native American groups that inhabit the Argentinean Patagonian provinces of Río Negro and Chubut. Fifteen autosomal STRs, 17 Y-STRs, mtDNA full length control region sequence and two sets of Y and mtDNA-coding region SNPs were analyzed in a set of 434 unrelated individuals. The sample set included two aboriginal groups, a group of individuals whose family name included Native American linguistic root and urban samples from Chubut, Río Negro and Buenos Aires provinces of Argentina. Specific Y Amerindian haplogroup Q1 was found in 87.5% in Mapuche and 58.82% in Tehuelche, while the Amerindian mtDNA haplogroups were present in all the aboriginal sample contributors investigated. Admixture analysis performed by means of autosomal and Y-STRs showed the highest degree of admixture in individuals carrying Mapuche surnames, followed by urban populations, and finally by isolated Native American populations as less degree of admixture. The study provided novel genetic information about the Mapuche and Tehuelche people and allowed us to establish a genetic correlation among individuals with Mapudungun surnames that demonstrates not only a linguistic but also a genetic relationship to the isolated aboriginal communities, representing a suitable proxy indicator for assessing genealogical background.

  14. Resistance of Fasciola hepatica against triclabendazole in cattle in Patagonia (Argentina).

    Science.gov (United States)

    Olaechea, F; Lovera, V; Larroza, M; Raffo, F; Cabrera, R

    2011-06-10

    In the winter of 2008, cattle on a farm in the province of Neuquen, Argentina died from subacute and chronic liver fluke disease despite four previous treatments with Triclabendazole (TCBZ). In the spring of 2009, a preliminary efficacy test revealed good performance using nitroxynil, whereas TCBZ efficacy was only 18% by egg counts of Fasciola eggs in the faeces. Resistance to Fasciola hepatica to TCBZ has never been reported in South America, so in January of 2010 a controlled trial was conducted to confirm and to define the degree of resistance in this herd. In a clinical trial, the fluke egg output was monitored on Days 14 and 21 and serum enzymes gamma-glutamyl transpeptidase (GGT) and glutamic-oxaloacetic transaminase (GOT) on Days 0 and 21 in 36 calves treated with TCBZ or with closantel. The results showed a reduction of 100% in fluke egg output at Days 14 and 21 for closantel. The mean epg in the TCBZ-treated groups did not decrease. Because of the fact that in this study TCBZ treatment in cattle had no effect, even at double the recommended dose, it is highly indicative that resistance of F. hepatica against TCBZ is present on this farm. The GGT and GOT levels decreased in the closantel-treated group as a result of the treatment at 21 days after dosing. To evaluate the importance of TCBZ resistance in F. hepatica in Argentina, a study on more farms from endemic areas is needed.

  15. Mortality of the outbreak defoliator Ormiscodes amphimone (Lepidoptera: Saturniidae) caused by natural enemies in northwestern Patagonia, Argentina Mortalidad del defoliador epidémico Ormiscodes amphimone (Lepidoptera: Saturniidae) causada por enemigos naturales en el noroeste de la Patagonia Argentina

    OpenAIRE

    JUAN PARITSIS; CAROLINA QUINTERO; THOMAS KITZBERGER; Veblen, Thomas T

    2012-01-01

    Outbreaks of the defoliator moth Ormiscodes amphimone are occurring more frequently in numerous Nothofagus forests of Patagonia. However, little is known about the life history of this species including its natural enemies as mortality agents. In this work we quantified mortality by parasitoids and generalist predators at the egg, larval and pupal life stages of O. amphimone in a Nothofagus pumilio (Poepp. & Endl.) Krasser forest in northwestern Patagonia. Parasitism of eggs was relatively lo...

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

    Directory of Open Access Journals (Sweden)

    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.

  17. 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.

  18. 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. PMID:22350107

  19. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Local extinctions in the small mammal’s assemblages between late Holocene and historical times in Talagapa mountains (Patagonia, Argentina: The role of land use changes

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    Analia Andrade

    2016-07-01

    Full Text Available The aim of this work was to evaluate possible changes in the small mammal composition in the Patagonian arid Extra-Andean steppes between the late Holocene and historical times. A bone sequence accumulated by the disintegration of owl pellets deposited inside a cave in the Talagapa mountains (Chubut province, Argentina was analyzed. The paleontological sequence encompasses a time span since 2.857 ± 50 years BP and 2.285 ± 40 years BP and was covered by a thick and compact layer of sheep feces that set the boundaries of historical times. Rodent prey were identified and quantified on the basis of skulls and mandible pairs and Holocene and historical assemblages were compared with those recovered from modern owl pellets collected in the area. The sharpest change appears in recent times, after the modification in the land use in the area, with local extinction of Loxodontomys micropus, a species associated with mesic habitats, and the apparent modification in the frequencies of certain species. Hypotheses about climatic, anthropic, and environmental factors that may have influenced those variations are discussed.

  2. 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

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

    OpenAIRE

    Isabelino A Siede; Elizabeth Guglielmino; Julia Alcain; Gabriela Fernández; Diana Guinao

    2015-01-01

    ¿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 provi...

  4. Formas terminales de Hippidion (Mammalia, Perissodactyla de los yacimientos del Pleistoceno Tardio-Holoceno de la Patagonia (Argentina y Chile

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    Prado, J. L.

    1987-04-01

    Full Text Available The present study is a revision of the terminal forms of the South-American horses coming from the archeological sites of Patagonia. They are compared with those from the Northwest of Argentine. The study also includes paleoenvironmental and cronological related aspects.El presente estudio comprende una revisión de las formas terminales de caballos sudamericanos recuperados de sitios arqueológicos de la Patagonia. Se comparan con las formas del noroeste argentino. Incluye aspectos paleoambientales y cronológicos relacionados.

  5. A Paleocene lowland macroflora from Patagonia reveals significantly greater richness than North American analogs

    Science.gov (United States)

    Iglesias, Ari; Wilf, Peter; Johnson, Kirk R.; Zamuner, Alba B.; Rubén Cúneo, N.; Matheos, Sergio D.; Singer, Bradley S.

    2007-10-01

    Few South American macrofloras of Paleocene age are known, and this limits our knowledge of diversity and composition between the end-Cretaceous event and the Eocene appearance of high floral diversity. We report new, unbiased collections of 2516 compression specimens from the Paleocene Salamanca Formation (ca. 61.7 Ma) from two localities in the Palacio de los Loros exposures in southern Chubut, Patagonia, Argentina. Our samples reveal considerably greater richness than was previously known from the Paleocene of Patagonia, including 36 species of angiosperm leaves as well as angiosperm fruits, flowers, and seeds; ferns; and conifer leaves, cones, and seeds. The floras, which are from siltstone and sandstone channel-fills deposited on low-relief floodplain landscapes in a humid, warm temperate climate, are climatically and paleoenvironmentally comparable to many quantitatively collected Paleocene floras from the Western Interior of North America. Adjusted for sample size, there are >50% more species at each Palacio de los Loros quarry than in any comparable U.S. Paleocene sample. These results indicate more vibrant terrestrial ecosystems in Patagonian than in North American floodplain environments ˜4 m.y. after the end-Cretaceous extinction, and they push back the time line 10 m.y. for the evolution of high floral diversity in South America. The cause of the dis parity is unknown but could involve reduced impact effects because of greater distance from the Chicxulub site, higher latest Cretaceous diversity, or faster recovery or immigration rates.

  6. Entre el "deber" y el "derecho": patrimonio arqueológico y obligaciones sociales en Patagonia Argentina Among "duty" and "rights": Archaeological heritage and social obligations in Argentine

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    Carolina Crespo

    2006-12-01

    Full Text Available En años recientes, los restos arqueológicos de varias provincias de la Patagonia han sido legislados bajo la categoría de "patrimonio cultural" de las mismas, regulándose su uso científico, cultural y, en ciertos casos, turístico. Sin embargo, más allá de los comportamientos reglados por el texto legal coexiste toda una serie de comportamientos y lazos sociales que se rigen bajo otras reglas o principios que trascienden el marco normativo. Motiva así, a este artículo, analizar los intercambios sociales que se entretejen por fuera del andamiaje institucional y jurídico alrededor de los bienes arqueológicos, específicamente del arte rupestre, en una ciudad de Patagonia. La importancia del análisis reside en el tipo de relaciones que se actualiza hoy alrededor de este patrimonio, el desplazamiento de sentidos que éstas impulsan sobre este bien y los efectos que generan en la gestión del mismo. El examen de las prestaciones y contraprestaciones, esto es, de las obligaciones mutuas que expresan, pretende servir como un ejemplo de la resignificación que en los últimos años adquieren los bienes arqueológicos y, específicamente el arte rupestre en la Patagonia Argentina, así como de las complejidades que reviste su gestión.In recent years the archaeological remains from several Patagonian provinces were legislated under the category of "cultural heritage," regulating their scientific, cultural and, in some cases, touristic use. Nevertheless, beyond the behaviors regulated by the legal text an entire series of behaviors and social connections coexist that is governed by other rules or principles which transcend the normative framework. As such, the goal of this paper is to analyze the social exchanges that are woven together beyond the institutional and legal scaffolding erected around archaeological goods - specifically rock art - in a Patagonian city. The relevance of the analysis lies in the type of relationships that are now

  7. 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 swe

  8. Un suelo referible al periodo calido medieval en Patagonia Austral y Tierra del Fuego (Argentina. Aspectos cronologicos y paleoclimaticos

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    Favier Dubois, C. M.

    2002-08-01

    Full Text Available Geoarchaeological work done in Southernmost Patagonia and in the north of Tierra del Fuego, have revealed the recurrent presence of a paedogenesis interval represented by a soil of an A-AC-C profile, with a mollic epipedon, in the upper section of eolian and colluvial deposits of the late Holocene. This soil is today buried in the sites that have been analyzed, while it remains exposed in other areas of the landscape. Radiocarbon dates obtained on materials placed below it (maximum ages and those obtained by OCR (Oxidizable Carbon Ratio in the AC horizon of this soil (minimum ages, indicate the beginning of its development around the year 1000 BP. Its chronology and environmental implications suggest a relationship with the medieval climatic fluctuations called Medieval Warm Period or Medieval Optimum in Europe. This period has correlates detected in Patagonia by dendroclimatic studies.Estudios geoarqueológicos realizados en 5 localidades de Patagonia austral y norte Tierra del Fuego han revelado la recurrente presencia de un suelo de perfil A-AC-C, de epipedon mólico, en depósitos eólicos y coluviales del Holoceno tardío. Este suelo se observa sepultado en los yacimientos arqueológicos analizados, mientras que permanece expuesto en otras posiciones del paisaje. Numerosas edades máximas y mínimas obtenidas por 14C y por la técnica de OCR (Oxidizable Carbon Ratio indican el comienzo de su desarrollo hacia el 1000 AP. Su cronología e implicancias ambientales permiten vincularlo con fluctuaciones climáticas desarrolladas durante el denominado Período Cálido Medieval u Optimo Medieval Europeo, con correlatos detectados en Patagonia a través de estudios dendroclimáticos.

  9. Mortality of the outbreak defoliator Ormiscodes amphimone (Lepidoptera: Saturniidae caused by natural enemies in northwestern Patagonia, Argentina Mortalidad del defoliador epidémico Ormiscodes amphimone (Lepidoptera: Saturniidae causada por enemigos naturales en el noroeste de la Patagonia Argentina

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    JUAN PARITSIS

    2012-03-01

    Full Text Available Outbreaks of the defoliator moth Ormiscodes amphimone are occurring more frequently in numerous Nothofagus forests of Patagonia. However, little is known about the life history of this species including its natural enemies as mortality agents. In this work we quantified mortality by parasitoids and generalist predators at the egg, larval and pupal life stages of O. amphimone in a Nothofagus pumilio (Poepp. & Endl. Krasser forest in northwestern Patagonia. Parasitism of eggs was relatively low (ca. 11 %, and we did not record significant larval predation by insectivorous birds. However, we recorded elevated mortality caused by larval parasitoids (ca. 50 % in third instar larvae and pupal predators (ca. 75 %, which suggests that these natural enemies could play a significant role in regulating O. amphimone populations. Our research is an initial step towards understanding the influence of natural enemies on O. amphimone population dynamics.Las irrupciones poblacionales de la polilla defoliadora Ormiscodes amphimone están ocurriendo de manera más frecuente en numerosos bosques de Nothofagus de la Patagonia. Sin embargo, se sabe poco de la historia natural de esta especie y, particularmente, de sus enemigos naturales. En este estudio se cuantificó la depredación de huevos, larvas y pupas de O. amphimone por parasitoides y otros depredadores en un bosque de Nothofagus pumilio (Poepp. & Endl. Krasser en el noroeste de la Patagonia. Se encontró que el parasitismo de huevos fue relativamente bajo (ca. 11 % y no se registró depredación significativa de larvas por aves insectívoras. No obstante, registramos niveles elevados de mortalidad causada por parasitoides de larvas (ca. 50 % en larvas en tercer instar y por depredadores de pupas (ca. 75 %, lo que parece indicar que estos enemigos naturales desempeñan un papel significativo en la regulación de poblaciones de O. amphimone. Este estudio representa un paso inicial hacia el entendimiento de la

  10. 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

    Full Text Available En los sistemas forestales, la hojarasca es generalmente la principal fuente de nutrientes para la vegetación y microorganismos, pudiendo variar éstos en relación a la biomasa y calidad de los materiales aportados por diferentes especies. Las raíces de los árboles ejercen influencia en el desarrollo y actividad de la microflora. El objetivo de este trabajo fue evaluar la influencia sobre el suelo de dos especies arbóreas implantadas, con distinta composición del residuo vegetal aportado al suelo. El suelo está clasificado como un Andisol y está ubicado en la Estación Forestal Trevelín, Chubut, Argentina, Lat. 43º Sur, Long 71º31´ Oeste. Se extrajeron muestras superficiales de suelo de dos parcelas de bosque con una especie dominante cada una: Pino radiata (Pinus radiata D. Don. y Roble europeo (Quercus robur. Se determinó carbono orgánico, respiración microbiana, actividad deshidrogenasa, diversidad funcional de comunidades microbianas asociadas y se calculó el índice de diversidad de Shanon Weaver (H. Se cuantificaron bacterias totales, bacterias amilolíticas, actinomicetes y hongos. Los valores de respiración microbiana y carbono orgánico resultaron significativamente superiores en el suelo debajo de Roble. No se encontraron diferencias significativas entre valores de deshidrogenasa. Los recuentos de flora bacteriana total y de bacterias amilolíticas dieron significativamente superiores en el suelo asociado a Roble, mientras que los actinomicetes y hongos no mostraron diferencias significativas entre especies. El análisis de componentes principales mostró variaciones significativas en la fisiología de las comunidades microbianas asociadas a estas dos especies. El índice de diversidad H de la microflora fue significativamente mayor para Pino. Los residuos de Roble por ser una especie latifoliada y por lo tanto poseer menor contenido de sustancias recalcitrantes que una conífera, asociado al mayor desarrollo de

  11. Juan Valentin: un gelogo que supo resumir la geologa argentina Juan Valentin: a geologist that compiled the geology of Argentina

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    Florencio Gilberto Aceolaza

    2011-09-01

    Full Text Available Juan Valentin fue un destacado gelogo alemn que arrib a nuestra patria en 1894 para integrarse a los equipos que entonces desarrollaban investigaciones desde el Museo de La Plata y el Museo Nacional de Buenos Aires. Su trabajo lo llev, inicialmente, a estudiar las sierras de Buenos Aires y luego tambin lo hizo en Crdoba, San Luis, Salta y Jujuy. Fue grande su actividad, motivo por el cual, se lo incorpor a la Sociedad Cientfica Argentina asumiendo la revisin y compaginacin de los Anales que en ese tiempo editaba la mencionada institucin. Esta actividad ms el conocimiento de campo logrado, lo llev a confeccionar un extenso artculo donde describi la geologa de la Argentina, el cual fue agregado a la edicin del Segundo Censo Nacional. A este trabajo se lo considera una importante sntesis sobre la constitucin geolgica del pas. Entusiasmado con el apoyo que vena logrando planific un programa de investigacin para desarrollar en el norte de la Patagonia e incrementar el conocimiento de la estratigrafa regional. As fue que, en octubre de en 1897, se dirigi a Puerto Madryn donde llev adelante sus primeros trabajos en el valle del ro Chubut y la zona de Cabo Raso. Revisando afloramientos en las cercanas de Aguada de Reyes muri en un fatal accidente, como dice la crnica, con sus bolsillos repletos de los fsiles que haba coleccionado. Haca poco ms de dos aos que se desempeaba en el pas y contaba con 30 aos recin cumplidos. La mencin histrica narra que su cuerpo fue sepultado en la ciudad de Rawson.Juan Valentin was a German geologist that arrived to Argentina in 1894 to join the staff members of the Museum of La Plata and the National Museum of Buenos Aires. His work initially took him to explore the Buenos Aires ranges, and then those of Crdoba, San Luis, Salta and Jujuy. He joined the Argentine Scientific Society, assuming the edition of the Annals. His activities and the achieved knowledge in the field led him to prepare a lengthy article describing the

  12. Cerro Bombero: registro de Hippidion saldiasi Roth, 1899 (Equidae, Perissodactyla en el Holoceno temprano de Patagonia (Santa Cruz, Argentina

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    Alberdi, M. T.

    2008-06-01

    Full Text Available A new record of Hippidion saldiasi with new radiocarbon data referred to early Holocene (8,850 ± 80 year C-14 B.P of Patagonia is reported. Both its peculiar geographic location in a scarcely prospected zone and its radiocarbon age, provide new elements to discuss the previous hypotheses about the extinction of the horses and its relations with the human beings that inhabited the different environments of South America.Presentamos un nuevo registro de Hippidion saldiasi con datación radiocarbónica directa correspondiente al Holoceno temprano de Patagonia (8.850 ± 80 años C-14 AP. Su particular ubicación temporal y geográfica en una zona poco estudiada hasta ahora y su registro reciente, aportan nuevos elementos para discutir las hipótesis previas sobre la extinción de los caballos y su relación con los grupos humanos que colonizaron los diferentes ambientes de América del Sur.

  13. 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. PMID:26089256

  14. 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.

  15. 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.

  16. Relative paleointensity of the geomagnetic field over the last 4,500 years BP from sediment cores of Laguna Chaltel (Patagonia, Argentina)

    Science.gov (United States)

    Gogorza, C. G.; Irurzun, M. A.; Sinito, A. M.; Aldana, M.; Fey, M.; Ohlendorf, C.; Zolitschka, B.

    2013-05-01

    One motivation to investigate the magnetism of rocks is to study the behaviour of Earth's magnetic field of the past. The magnetic field is a vector field, having both direction and intensity. A complete understanding of it requires the study of all vector properties. However, paleointensity determinations are much more difficult than directions alone. This is one reason why the majority of paleomagnetic studies is concerned only with the directional variability of the magnetic field. Four short gravity cores from Laguna Chaltel in Patagonia, Argentina (49° 57'S, 71° 06'W) have been used to estimate the regional geomagnetic paleointensity. Measurements of intensity and directions of Natural Remanent Magnetization (NRM), magnetic susceptibility (k), isothermal remanent magnetization (IRM), saturation isothermal remanent magnetization (SIRM), as well as back field and anhysteretic remanent magnetization at 100 mT (ARM100mT) were performed and associated parameters calculated (ARM100mT/k, SIRM/ ARM100mT). In order to identify the magnetic mineralogy of the samples, IRM curves of a group of pilot samples were decomposed applying a Direct Signal Analysis (DSA) (Aldana et al., 2011). Results indicate the presence of magnetite, with logB1/2=1.8 and a relative proportion of 80%. Two other magnetic phases are observed at lower and higher logB1/2 values, probably greigite and goethite, respectively. DSA also indicates that the relative proportion of these minerals is the same in all samples analyzed. Studies also show that the magnetic grain size varies between 1 and 8 μm and that their concentration is between 0.01 and 0.08%. This range of the studied parameters indicates that our samples are suitable for paleointensity studies. The remanent magnetization at 15 mT (NRM15mT) has been normalized using the anhysteretic remanent magnetization at 15 mT (ARM15 mT), the saturation of isothermal remanent magnetization at 15 mT (SIRM15mT) and low field magnetic susceptibility (k

  17. 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

  18. Temperature and foliage quality affect performance of the outbreak defoliator Ormiscodes amphimone (F. (Lepidoptera: Saturniidae in northwestern Patagonia, Argentina La temperatura y la calidad del follaje afectan el desempeño del defoliador epidémico Ormiscodes amphimone (F. (Lepidoptera: Saturniidae en el noroeste de la Patagonia argentina

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    JUAN PARITSIS

    2010-12-01

    Full Text Available In the temperate forests of Chile and Argentina the phytophagous moth Ormiscodes amphimone (F. causes severe defoliation on the southern beech tree Nothofagus pumilio (Poepp. & Endl. Krasser. The recent increase in defoliation frequency in some áreas appears to be influenced by a warmer climate. To evalúate the effects of temperature and the spatial heterogeneity of foliage quality on the performance and relative consumption rate of O. amphimone in northwestern Patagonia, Argentina we conducted a factorial experiment. Larval performance was measured as relative growth rate, developmental time, larval survival, and pupal weight. Larvae of O. amphimone were reared under two constant temperature regimes (15 °C and 20 °C and fed with two N. pumilio foliage types (from a mesic and from a xeric site. Larvae at the higher temperature and fed with leaves from the mesic site showed higher performance and consumption rate than larvae in the other treatments. Higher temperature and mesic foliage had positive effects on O. amphimone's relative growth rate, development time and relative consumption rate. However, pupal weight was positively influenced by mesic foliage but not by temperature, and larval survival did not show significant differences among treatments. Our results preliminarily suggest that O. amphimone performance and consumption rate may increase under higher temperature conditions, especially in the mesic portions of the precipitation gradient. However, these findings should be carefully interpreted as further research is necessary to assess the influence of higher temperatures on the foliar quality of N. pumilio.En los bosques templados de Chile y Argentina la polilla fitófaga Ormiscodes amphimone (F. genera severas defoliaciones sobre la lenga (Nothofagus pumilio [Poepp. & Endl.] Krasser. El reciente aumento en la frecuencia de defoliación en algunas áreas de la Patagonia parecería estar influenciada por un clima más cálido. Para

  19. 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

    OpenAIRE

    VALERIA OJEDA; MARIANO GELAIN; LORENZO SYMPSON; ANA TREJO

    2003-01-01

    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 mo...

  20. 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

  1. Characterization of black volcanites from the Limay river basin, Patagonia, Argentina, using energy dispersive X-ray fluorescence spectrometry: an aid to infer human group mobility

    International Nuclear Information System (INIS)

    The investigation of hunter-gatherers archaeological sites in the Limay river basin, Patagonia, Argentina, raised questions concerning the lithic technology. The chemical characterization of artifacts, rocks and possible sources of provenances could help to elucidate the hunter-gatherer mobility. In three archaeological sites-Rincon Chico 2 (RCh2/87; 14C 710 ± 60 BP), Cueva Traful I (CTI; 14C 9430 ± 230 BP) and Casa de Piedra de Ortega (CPO; 14C 2840 ± 80 BP), tools and debitage or discarded flakes made in black volcanic rock have been found. Nearby an extensive rock outcrop of black volcanite, Paso Limay quarry (CPL), with similar characteristics was located. Samples coming from these four sites were analyzed by energy dispersive X-ray fluorescence spectrometry. This characterization allowed the geochemical classification of the lithic material and to correlate the samples with the suspected source after a previous statistical analysis. The majority of the samples were classified as dacites and rhyolites. Only samples coming from CPO site, the closest place to CPL were made exclusively with the quarry rocks. A set of five samples from RCh2/87 and two samples from CTI appear to have same chemical composition as CPL in spite of this site is placed in the opposite bank of the Limay river suggesting that hunter-gatherers could accede to the quarry, eventually. Finally, only a set of five samples coming from RCh2/87 and CTI do not group with the quarry. This fact evidences the existence of secondary sources of supply. The information of this research allowed inferring ancient human mobility patterns in the region. (author)

  2. Vulnerability to climate warming of Liolaemus pictus (Squamata, Liolaemidae), a lizard from the cold temperate climate in Patagonia, Argentina.

    Science.gov (United States)

    Kubisch, Erika Leticia; Fernández, Jimena Beatriz; Ibargüengoytía, Nora Ruth

    2016-02-01

    The vulnerability of populations and species to global warming depends not only on the environmental temperatures, but also on the behavioral and physiological abilities to respond to these changes. In this sense, the knowledge of an organism's sensitivity to temperature variation is essential to predict potential responses to climate warming. In particular, it is interesting to know how close species are to their thermal limits in nature and whether physiological plasticity is a potential short-term response to warming climates. We exposed Liolaemus pictus lizards, from northern Patagonia, to either 21 or 31 °C for 30 days to compare the effects of these treatments on thermal sensitivity in 1 and 0.2 m runs, preferred body temperature (T pref), panting threshold (T pant), and critical minimum temperature (CTMin). Furthermore, we measured the availability of thermal microenvironments (operative temperatures; T e) to measure how close L. pictus is, in nature, to its optimal locomotor performance (T o) and thermal limits. L. pictus showed limited physiological plasticity, since the acclimation temperature (21 and 31 °C) did not affect the locomotor performance nor did it affect T pref, the T pant, or the CTMin. The mean T e was close to T o and was 17 °C lower than the CTMax. The results suggest that L. pictus, in a climate change scenario, could be vulnerable to the predicted temperature increment, as this species currently lives in an environment with temperatures close to their highest locomotor temperature threshold, and because they showed limited acclimation capacity to adjust to new thermal conditions by physiological plasticity. Nevertheless, L. pictus can run at 80 % or faster of its maximum speed across a wide range of temperatures near T o, an ability which would attenuate the impact of global warming.

  3. Relationship between Bajo Pobre and Chon Aike formations (Deseado Massif, Patagonia, Argentina):a melt inclusions study

    Science.gov (United States)

    Busà, T.; Bellieni, G.; Fernandez, R.; Hecheveste, H.; Piccirillo, E. M.

    2003-04-01

    The Deseado Massif covers the centre-east of the Santa Cruz Province, in the extra-Andean Patagonia. Although the Deseado Massif is mainly composed of silicic volcanic rocks (Chon Aike Formation, CA; 151.5 ±0.5 - 177.8 ±0.4 Ma), mafic and intermediate volcanites (Bajo Pobre Formation, BP; 152.7 ±0.5 and 164 ±0.3 Ma) outcrop largely in the central part of the Massif. In this paper quarz-trapped melt inclusions (rhyolitic in composition) from selected samples of the BP and the CA are analysed. On the basis of major elements content, for BP the sequence from andesite (BP whole rock) to ryholite (trapped as inclusions in quartz) can be modelled by simple fractional crystallisation of ortho- and clinopyroxene, plagioclase, quartz and apatite. As regards trace elements, a good calculated/measured ratio (around 1 ±0.2) is obtained assuming only a relatively high apatite fractionation. Since the apatite fractionation amount is not acceptable for major elements, the evolution of BP Formation cannot be modelled by a simple process of fractional crystallisation, and a contamination process probably occurred. The sequence from BP to CA cannot be modelled by fractional crystallisation. 30% batch melting of BP andesite (BP whole rock) produces a magma from which the CA ryholites (trapped as inclusions in quartz) can be obtained by Rayleigh fractional crystallisation of ortho- and clinopyroxene, plagioclase, magnetite, quartz, apatite and small amounts of zircon and minor allanite. Since the latter one was not observed in the analysed sample, a contamination process during magma evolution cannot be completely excluded. Finally, on the basis of the different trace elements concentration (Nb anomaly, different content in LILE, B/Be and B/Nb), it is possible to suppose that, at the time of the BP and CA emplacement, a changing in the tectonic setting, from subduction to a lithospheric extension, was active.

  4. Meltwater palaeohydrology of the Baker River basin (Chile/Argentina) during Late Pleistocene deglaciation of the Northern Patagonia Icefield

    Science.gov (United States)

    Thorndycraft, Varyl; Bendle, Jacob; Benito, Gerardo; Sancho, Carlos; Palmer, Adrian; Rodríguez, Xavier

    2016-04-01

    The Late Pleistocene deglaciation of the Northern Patagonia Icefield (NPI) was characterised by rapid ice sheet thinning and retreat, and the development of large proglacial lake systems characterised by continental scale drainage reversals. In this region, research has focused primarily on the identification of former ice-limits (e.g. moraine ridges) for geochronological analyses, with little attention given to the meltwater palaeohydrology of major river valleys. The Baker River catchment drains the majority of the eastern ice shed of the NPI, with a basin area of 29,000 km2 that includes the large transboundary lakes of General Carrera/Buenos Aires and Cochrane/Puerreydón. The Baker River valley is aligned north to south, crossing the east-west valleys of the main NPI outflow glaciers, and thus represents an important aspect of regional Late Pleistocene palaeogeography. The Baker River valley therefore has the potential to refine regional models of deglaciation through better understanding of relationships between glacier dynamics, ice dammed lakes and meltwater pathways. Here we present geomorphological mapping from the Atlantic-Pacific drainage divide (over 150 km east of the Cordillera) to the lower Baker valley, in order to reconstruct Late Pleistocene palaeohydrology. We provide new mapping of palaeolake shoreline elevations and evidence for glacial lake outburst flood (GLOF) pathways that require a re-evaluation of the currently accepted palaeogeographic models. For example, the palaeohydrological evidence does not support existing models of a unified Buenos Aires/Puerreydón mega-lake at ca. 400m elevation. We propose a relative chronology of palaeohydrological events that help refine the published moraine chronology derived from cosmogenic nuclide exposure dating. Controls on Late Pleistocene meltwater palaeohydrology of the Baker catchment are discussed, including the interplay of glacial processes and regional tectonics, in particular, dynamic

  5. The Bajada del Diablo astrobleme-strewn field, central Patagonia Argentina: Extending the exploration to surrounding areas

    Science.gov (United States)

    Acevedo, R. D.; Rabassa, J.; Ponce, J. F.; Martínez, O.; Orgeira, M. J.; Prezzi, C.; Corbella, H.; González-Guillot, M.; Rocca, M.; Subías, I.; Vásquez, C.

    2012-10-01

    The Bajada del Diablo astrobleme-strewn field is a huge domain of enigmatic circular structures located in central Patagonia. Three more localities are herein described, adding to the first area studied so far. Taking into consideration the four areas, a single, blurred crater dispersion ellipse has been identified. The four sectors now have been investigated, mapped, and georreferenced. Their circular structures, with a total of 185 (some of which are partially obliterated by erosion or sediment accumulation), were identified by remote sensing techniques, but many have been evaluated in situ and interpreted as impact craters. Moreover, two of the structures have been surveyed in detail in the field using a total station instrument. In addition to the previously known occurrence of circular structures on the Eruptive Complex Quiñelaf (Miocene basalts), the Pampa Sastre Fm. (Pliocene conglomerates), and of the Pleistocene pediment gravels and sands, and the geomorphological inferences that have suggested the extra-terrestrial origin of this event, we should now add that the recurrent absence of the cited Pliocene stratigraphic unit at the bottom of the craters is found in the pediment gravel and sands. Its removal has been interpreted as directly related to the impact, according to the magnetometric record of existing magnetic anomalies. Other preliminary observations on the collected samples (glass, breccias, and, most relevant, Fe-Ni-bearing spherules picked up within the impact zones) are herein discussed. Two hypotheses have been put forward about the nature of the possible impacting object that formed these astroblemes which, fragmented into hundreds of pieces, hit the surface of the Earth most likely in middle Pleistocene times. One of these hypotheses is related to the impact of a disintegrated asteroid of the rubble pile type, whereas a second hypothesis refers to the collision of a split comet with the Earth surface. The latter hypothesis is favoured since

  6. ON THE UNDERSTANDING OF AEOLIAN SEQUENCE STRATIGRAPHY: AN EXAMPLE FROM MIOCENE-PLIOCENE DEPOSITS IN PATAGONIA, ARGENTINA

    Directory of Open Access Journals (Sweden)

    CARLOS ZAVALA

    2001-07-01

    Full Text Available Upper Tertiary aeolian strata (Río Negro Formation outcrop in extensive sea cliffs at the Northeast of Patagonia. These outcrops show deposits corresponding to a complete suite of aeolian and aeolian related sub-environments, and also provide excellent exposures to analyse the sedimentology and internal architecture from a sequence stratigraphic point of view. Field studies, supplemented withline-drawings of oblique photographs, allowed the recognition of seven aeolian depositional sequences within the succession, each one bounded by regional super surfaces (or deflation surfaces. Internally these aeolian sequences display a cyclic recurrence in facies, that yields a tentative genetic model for their evolution. As documented from field examples, each basic aeolian depositional sequence was deposited during a single aggradational period, and is bounded by unconformities related to degradational periods. Degradational periods are regional deflationary events, that resulted in deep-scoured to flat surfaces, characterised by erosion / non deposition in which the only recognised accumulation is isolated and large angular blocks of fine-grained aggregates, interpreted as residual remnants of deposits of the previous sequence. Aggradational periods are characterised by a near- continuous accumulations responsible for the sequence building. Differences in the aeolian sediment budget to the area and the rising rate of water table control the related facies types, and allow to discriminateearly and late aggradational sub-periods. Early aggradational sub-periods form under conditions of relatively fast rising water tables associated with moderate aeolian sediment budget, thus resulting in the development of extended wet interduneslaterally associated with aeolian dunes and dry interdunes. During late aggradational sub-periods, the depositional surface outdistanced the water table, and aeolian dunes and dry interdunes tend to predominate. This sub

  7. Borrelia burgdorferi sensu lato in Ixodes cf. neuquenensis and Ixodes sigelos ticks from the Patagonian region of Argentina.

    Science.gov (United States)

    Sebastian, Patrick S; Bottero, Maria Noelia Saracho; Carvalho, Luis; Mackenstedt, Ute; Lareschi, Marcela; Venzal, José M; Nava, Santiago

    2016-10-01

    This study was conducted to detect Borrelia burgdorferi sensu lato infection in ixodid ticks from the Patagonia region in the south of Argentina. Therefore, ticks were collected on rodents in the provinces of Chubut, Río Negro and Santa Cruz. These ticks were identified as nymphs of Ixodes cf. neuquenensis and Ixodes sigelos. The B. burgdorferi s.l. infection was tested by a battery of PCR methods targeting the gene flagellin (fla) and the rrfA-rrlB intergenic spacer region (IGS). Three pools of I. sigelos nymphs from Chubut and Santa Cruz provinces as well as one pool of I. cf. neuquenensis nymphs from Río Negro province were tested positive in the fla-PCR. The samples of I. sigelos were also positive for the IGS-PCR. Phylogenetically, the haplotypes found in the positive ticks belong to the B. burgdorferi s.l. complex, and they were closely related to Borrelia chilensis, a genospecies isolated from Ixodes stilesi in Chile. The pathogenic relevance of the Borrelia genospecies detected in both I. neuquenensis and I. sigelos is unknown. PMID:27372197

  8. Infestación de Megastigmus aculeatus (Hymenoptera: Chalcidoidea en las semillas de rosas exóticas invasoras de comunidades naturales de la Patagonia andina de Argentina Megastigmus aculeatus infestation on seeds of exotic roses invading wild communities of Andean Patagonia from Argentina

    Directory of Open Access Journals (Sweden)

    KAREN D LEDIUK

    2012-03-01

    Full Text Available Megastigmus aculeatus Swederus (Hymenoptera: Chalcidoidea infesta las semillas de especies de Rosa tanto en las áreas de origen como en las de invasión. La larva de la avispa se desarrolla consumiendo la totalidad de la semilla. Se analizó la infestación de M. aculeatus en diferentes poblaciones de Rosa rubiginosa L. y Rosa canina L. y en plantas aisladas de Rosa multiflora Thunb. en áreas naturales del Noroeste de la Patagonia, Argentina. En R. rubiginosa, la especie más abundante, estudiamos la prevalencia y éxito de infestación por la avispa y el posible efecto sobre el tamaño del fruto. En este trabajo se presentan los primeros registros de R. rubiginosa y R. canina como especies hospedadoras de M. aculeatus en Argentina y se verifica su ausencia en las semillas de R. multiflora. En R. canina, el porcentaje de frutos infestados por M. aculeatus fue bajo (0-1 % por sitio, no siendo probablemente un factor condicionante de la reducida distribución de la planta. En R. rubiginosa, ese porcentaje fue alto (31-75 % de frutos infestados por sitio, pero solo el 2-8 % de los aquenios estaban infestados. Considerando los sitios analizados, la distribución a nivel regional de la infestación por M. aculeatus en las especies de rosas estudiadas es reducida. El tamaño del fruto no es afectado por la infestación del insecto. Los resultados de este trabajo muestran un bajo impacto actual de M. aculeatus en el control natural de la invasión de las rosas en la región andina de Argentina. Sin embargo, dado que las poblaciones de M. aculeatus podrían ser afectadas por la temperatura, un cambio en esta variable podría incrementar la prevalencia de infestación de las semillas de estos arbustos a mediano y largo plazo.Megastigmus aculeatus Swederus (Hymenoptera: Chalcidoidea infest Rosa species seeds both at the origin and invasion areas. The wasp larvae develop by consuming the entire seed. The M. aculeatus infestation was analyzed at different

  9. Lichen Usnea barbata as biomonitor of airborne elements deposition in the Province of Tierra del Fuego (southern Patagonia, Argentina).

    Science.gov (United States)

    Conti, Marcelo Enrique; Pino, Anna; Botrè, Francesco; Bocca, Beatrice; Alimonti, Alessandro

    2009-05-01

    Lichen Usnea barbata was tested as a possible biomonitor of atmospheric deposition in a supposedly pristine environment Tierra del Fuego (Argentina). Lichen samples were collected in 2005 and again in 2006 in 71 sites covering almost the entire region. The aim of the study was to evaluate the bioaccumulation of 26 elements in order to define the background levels in the region. The quantification was carried out by the sector field inductively coupled plasma mass spectrometry. No relevant temporal accumulation patterns between 2005 and 2006 sampling campaigns were observed. Then, the results were submitted to multivariate statistical analysis (cluster and principal component analyses). Cluster analysis produced a dendrogram where the 71 sites were divided into four clusters at (Dlink/Dmax)100Ushuaia-Road 3 (E area) and it was characterized by high levels of Cd, Co, Ni, Pb, Sb, and W in lichens. The present study has revealed the good capacity of U. barbata to reflect the baseline levels of elements in the environment at a regional scale level. The presence of certain level of elements in lichens agrees with the hypothesis that Tierra del Fuego is not a relatively pristine environment as occasionally supposed. However, when comparing our results with other countries, Tierra del Fuego lichens have a very low content of the measured elements. PMID:19232724

  10. A new lizard species of the Phymaturus patagonicus group (Squamata: Liolaemini) from northern Patagonia, Neuquén, Argentina.

    Science.gov (United States)

    Marín, Andrea González; Pérez, Cristian Hernán Fulvio; Minoli, Ignacio; Morando, Mariana; Avila, Luciano Javier

    2016-01-01

    The integrative taxonomy framework allows developing robust hypotheses of species limits based on the integration of results from different data sets and analytical methods. In this work, we test a candidate species hypothesis previously suggested based on molecular data, with geometric and traditional morphometrics analyses (multivariate and univariate). This new lizard species is part of the Phymaturus patagonicus group (payuniae clade) that is distributed in Neuquén and Mendoza provinces (Argentina). Our results showed that Phymaturus rahuensis sp. nov. differs from the other species of the payuniae clade by a higher number of midbody scales, and fewer supralabials scales, finger lamellae and toe lamellae. Also, its multidimensional spaces, both based on continuous lineal variables and geometric morphometrics (shape) characters, do not overlap with those of the other species in this clade. The results of the morphometric and geometric morphometric analyses presented here, coupled with previously published molecular data, represent three independent lines of evidence that support the diagnosis of this new taxon. PMID:27395232

  11. Estratigrafía y petrología del sector noreste de sierra de Apas. Provincia del Chubut Stratigraphy and petrology of the Northeastern sector of Sierra de Apas. Chubut Province

    OpenAIRE

    M. Remesal; F.M. Salani; G.I. Massaferro; M.E. Cerredo

    2004-01-01

    La sierra de Apas, ubicada entre las provincias de Rio Negro y Chubut, forma parte del magmatismo de intraplaca emplazado durante el Paleogeno-Neógeno en el norte de la Patagonia extrandina. En el sector noreste se ha definido una estratigrafía integrada por: traquitas oscuras, flujos piroclásticos, traquitas claras, domos riolíticos y basaltos porfíricos y afíricos. Las traquitas oscuras, son relativamente más antiguas, tienen bajo porcentaje de fenocristales, y clasifican como traquitas- be...

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

    Directory of Open Access Journals (Sweden)

    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

  13. Estratigrafía y petrología del sector noreste de sierra de Apas. Provincia del Chubut

    OpenAIRE

    M. Remesal; F.M. Salani; G.I. Massaferro; M.E. Cerredo

    2004-01-01

    La sierra de Apas, ubicada entre las provincias de Rio Negro y Chubut, forma parte del magmatismo de intraplaca emplazado durante el Paleogeno-Neógeno en el norte de la Patagonia extrandina. En el sector noreste se ha definido una estratigrafía integrada por: traquitas oscuras, flujos piroclásticos, traquitas claras, domos riolíticos y basaltos porfíricos y afíricos. Las traquitas oscuras, son relativamente más antiguas, tienen bajo porcentaje de fenocristales, y clasifican como traquitas- be...

  14. Salud bucal y nutrición en cazadores-recolectores del nordeste del Chubut en el Holoceno

    OpenAIRE

    Novellino, Paula; Gómez Otero, Julieta

    2009-01-01

    Investigaciones arqueológicas llevadas a cabo en Patagonia centro-septentrional (costa atlántica y valle inferior del río Chubut) demostraron que el área fue utilizada desde por lo menos el Holoceno medio. Estudios de isótopos estables ( 13C y 15N) en muestras óseas humanas indican que los cazadores-recolectores que la ocuparon mantuvieron una dieta mixta que combinó el consumo de guanacos, plantas terrestres, moluscos y pinnípedos. No obstante esta tendencia general, se observó variabilidad ...

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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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

    Directory of Open Access Journals (Sweden)

    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.

  17. Peat-bog accumulation rate in the Andes of Tierra del Fuego and Patagonia (Argentina and Chile) during the last 43,000 years

    Energy Technology Data Exchange (ETDEWEB)

    Rabassa, J.; Heusser, C.J.; Coronato, A. (CADIC-CONICET, Ushuaia (Argentina))

    1989-01-01

    Profiles of biogenic deposits formed in peat-bogs and lakes of Tierra del Fuego and Patagonia have been analysed in order to ascertain their internal structure and the accumulation rate of organic matter. This rate, estimated between 0.5 y 0.7 mm/yr for the Late Quaternary, reflects, among other factors, climatic changes and the compaction processes of the sediments. 9 refs., 3 tabs., 3 figs.

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

    OpenAIRE

    Rocio Loizaga de Castro; Silvana Laura Dans; Mariano Alberto Coscarella; Enrique Alberto Crespo

    2013-01-01

    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...

  19. Unravelling the collapse mechanisms at a Jurassic caldera of the Chon Aike silicic LIP in Southern Patagonia (47° 15 'S, 71° 40'W), Argentina

    Science.gov (United States)

    Sruoga, P.; Japas, S.; Salani, F.; Kleiman, L.; Graffigna, M.

    2008-10-01

    La Peligrosa Caldera is located at Sierra Colorada (47° 15'S, 71° 40' W) in the Chon-Aike silicic LIP. It represents an unique window to understand the eruptive mechanisms that prevailed throughout the ignimbritic flare-up in Southern Patagonia during middle to late Jurassic times. Key pieces of lithologic and structural evidences are taken into account to reconstruct the volcanic structure.

  20. Nacionalismo territorialista en textos escolares: representaciones de la Patagonia en la dictadura militar argentina (1966-1983 Territorialist nationalism in school textbooks: representations of Patagonia in Argentinian military dictatorship (1966-1983

    Directory of Open Access Journals (Sweden)

    Jesús Jaramillo

    2012-03-01

    Full Text Available Los textos escolares desde hace tiempo se han constituido en una de las fuentes primarias para el campo de la Historia de la Educación en tanto son instrumentos de socialización formal básica. Sea considerado registro escrito editorial, herramienta didáctica o registro de memoria escolar, los textos escolares instituyen - y, en ocasiones, eternizan - concepciones e intereses reflejados en sus contenidos "oficiales". Investigaciones recientes en la búsqueda de la realidad escolar han enfatizado la importancia de los mismos en la construcción de las identidades nacionales, pero también de las identidades de grupos socio-culturales, socio-étnicos y regionales. Este artículo, a partir de una indagación historiográfica sobre libros de lectura, intenta reconstruir las diferentes tramas discursivas textuales e iconográficas en que ha sido representada la Patagonia durante los periodos dictatoriales argentinos 1966-1973 y 1976-1983, en escuelas primarias de Río Negro y Neuquén. En principio, puede advertirse un conjunto de relatos de la Patagonia y sus habitantes sobre la base de tres núcleos de sentido: el de territorio indígena, desierto e inculto; el de promisión para el progreso y el turismo; y el de soberanía nacional. A través de sus argumentos daremos cuenta que los libros escolares de edición nacional con rasgos eminentemente políticos pero también étnicos y raciales fueron medios de formación y, sobre todo, dispositivos que coadyuvaron a la conformación de una línea ideológica, política y pedagógica propia del nacionalismo católico militar.School textbooks have long been taken as one of the primary sources for the field of the History of Education, since they are instruments of basic formal socializing. Either as editorial written records, as didactic tools, or as records of school memory, school textbooks institute - and sometimes crystallize - conceptions and interests reflected in their "official" contents

  1. Argentina

    International Nuclear Information System (INIS)

    The history of Argentina nuclear development can be summarized into two periods: 'splendour' and 'stand-by'. The former starting in the decade of the 1950s until the late 1970s while the latter period goes from the late 1970s to 2006. The first period (1950-1980) was characterized by a national policy of scientific and technological development; State intervention in the area of industrial production. The military aspects, if any, were marginal in the context of the overall development. During this period, important public scientific technological projects were carried out: the production and sale of experimental reactors, nuclear plants (Atucha I and Embalse), and some projects aimed to developing national industry. The stimulus experienced in the country in this period accompanied the role of nuclear technology worldwide due to the Cold War and the persuasion factor among the main powers. However, during the 1970s and 1980s the whole world started questioning these technologies which ran parallel to the liberalization of the countries economies. The second period (1980s onwards) was characterized by many economic problems and the consequent transitory stop of national nuclear projects; e.g. Argentina transitory stopped its third nuclear plant (at present under construction). At that moment, neoliberal politics were aimed at reducing the role of the State and promoting privatization, separating nuclear projects from governmental control, trying to privatize the nuclear plants, and cutting scientific budgets. Argentina has two nuclear power plants in operation providing 8.6% of the total country's electricity. A third one, 692 MW(e) power reactor PHWR Atucha-2 construction was stopped in the 1990s and re-started in 2007 it is expected to be in commercial operation by 2011). Argentina nuclear power plants utility, NA S.A. is preparing the refurbishment of its CANDU-6 reactor. Argentina Atomic Energy Commission (CNEA) has a prototype of its CAREM nuclear power plant

  2. 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.

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

    Science.gov (United States)

    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.

  4. Precipitation origin and evaporation of lakes in semi-arid Patagonia (Argentina) inferred from stable isotopes ( δ18O, δ2H)

    Science.gov (United States)

    Mayr, Christoph; Lücke, Andreas; Stichler, Willibald; Trimborn, Peter; Ercolano, Bettina; Oliva, Gabriel; Ohlendorf, Christian; Soto, Julio; Fey, Michael; Haberzettl, Torsten; Janssen, Stephanie; Schäbitz, Frank; Schleser, Gerhard H.; Wille, Michael; Zolitschka, Bernd

    2007-02-01

    Stable isotope approaches are often used for estimating water balances of lakes. Such studies require regional background information about hydrogen and oxygen isotope variability of lakes and their potential inflows. Here, a stable isotope database ( δ2H and δ18O) is presented for estimating evaporation to inflow ratios ( E/ I) of lakes in semi-arid southern Patagonia. Water samples of 23 lakes and ponds located in the Patagonian steppe at about 52°S were sampled during three subsequent austral summers. Two deep crater lakes, Laguna Azul and Laguna Potrok Aike, were studied in more detail during a two-years monitoring. Furthermore, precipitation, groundwater and atmospheric water vapor were sampled for isotope analyses. Presented data imply that the isotopic composition of rainfall in southeastern Patagonia is predominantly determined by precipitation amount and moisture source area. For the investigated area, the first meteoric water and evaporation lines in δ2H vs. δ18O space are presented. The database was further used to estimate the water balances of the two crater lakes, Laguna Azul and Laguna Potrok Aike, which are in the focus of recent paleoclimatic investigations. According to that approach about 50% and 60%, respectively, of the water entering Laguna Azul and Laguna Potrok Aike via surface and subsurface inflow evaporates. These results testify a considerable flow of lake waters into the groundwater.

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

    Directory of Open Access Journals (Sweden)

    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.

  6. 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

    Directory of Open Access Journals (Sweden)

    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

  7. 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

  8. Juan Valentin: un gelogo que supo resumir la geologa argentina

    Directory of Open Access Journals (Sweden)

    Florencio Gilberto Aceolaza

    2011-09-01

    Full Text Available Juan Valentin fue un destacado gelogo alemn que arrib a nuestra patria en 1894 para integrarse a los equipos que entonces desarrollaban investigaciones desde el Museo de La Plata y el Museo Nacional de Buenos Aires. Su trabajo lo llev, inicialmente, a estudiar las sierras de Buenos Aires y luego tambin lo hizo en Crdoba, San Luis, Salta y Jujuy. Fue grande su actividad, motivo por el cual, se lo incorpor a la Sociedad Cientfica Argentina asumiendo la revisin y compaginacin de los Anales que en ese tiempo editaba la mencionada institucin. Esta actividad ms el conocimiento de campo logrado, lo llev a confeccionar un extenso artculo donde describi la geologa de la Argentina, el cual fue agregado a la edicin del Segundo Censo Nacional. A este trabajo se lo considera una importante sntesis sobre la constitucin geolgica del pas. Entusiasmado con el apoyo que vena logrando planific un programa de investigacin para desarrollar en el norte de la Patagonia e incrementar el conocimiento de la estratigrafa regional. As fue que, en octubre de en 1897, se dirigi a Puerto Madryn donde llev adelante sus primeros trabajos en el valle del ro Chubut y la zona de Cabo Raso. Revisando afloramientos en las cercanas de Aguada de Reyes muri en un fatal accidente, como dice la crnica, con sus bolsillos repletos de los fsiles que haba coleccionado. Haca poco ms de dos aos que se desempeaba en el pas y contaba con 30 aos recin cumplidos. La mencin histrica narra que su cuerpo fue sepultado en la ciudad de Rawson.

  9. 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 ...

  10. Argentina.

    Science.gov (United States)

    1993-02-01

    Background notes on Argentina provide a profile of the geography, selected demographic features, government and economic conditions. Descriptive text includes a discussion of the people, their history and political conditions, the government and officials, the state of the economy, their defense, foreign relations, and relations with the US. The 1992 estimated population was about 33 million of whom 97% are European (mostly Spanish and Italian). Religions represented are Roman Catholic (92%), Protestant (2%), Jewish (2%), and other (4%). Adult literacy is 95%. 36% are engaged in industry and commerce, 20% in services, 19% in agriculture, 6% in transport and communications, and 19% other. Per capita gross domestic product was $4,500. There are only 50,000 native Indians remaining in peripheral provinces. The population enjoys a high standard of living and a low growth rate. The country was shaped by dominant forces: modern agricultural techniques and the integration of the country into the world economy. Foreign investment aided the economic revolution. Conservative and radical rule has swung the country back and forth politically since 1916. Colonel Juan Domingo Peron led a successful military coup in 1943 and was elected in 1946. Policies were instituted to give a greater voice to the working class, and with the influences of his wife, women's groups. In 1955, he was ousted by the military, which failed to revive the economy and quiet increasing terrorism. After a number of difficult elections, Peron was reinstated as president in 1973. Extremists on the left and right threatened public order; the military as a consequence imprisoned persons indefinitely. Peron's wife succeeded him after his death, but was removed from office in the military coup of 1976. Basic human rights were violated during this period. By 1983, a fair election was held and support increased for a democratic system. In 1989, Carlos Saul Menem, a Peronist candidate, won and established

  11. 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...

  12. Philureter trigoniopsis, a new genus and species (Dactylogyridae, Ancyrocephalinae) from the ureters and urinary bladder of Galaxias maculatus (Osmeriformes: Galaxiidae) in Patagonia (Argentina).

    Science.gov (United States)

    Viozzi, G P; Gutiérrez, P A

    2001-04-01

    The monotypic Philureter n. gen. (Ancyrocephalinae; Dactylogyridae) is proposed to accommodate Philureter trigoniopsis n. sp. with the following features: presence of a cuplike ventral haptor armed with 14 hooks and 2 anchor/bar complexes; dorsal pair of anchors poorly defined and variable in shape, 1 frequently absent; tandem, intercecal gonads, testis bilaterally lobulated. Philureter trigoniopsis n. sp. is described from the ureters and urinary bladder of Galaxias maculatus (Jenyns, 1842) (Osmeriformes) in Patagonian Andean lakes, Argentina. PMID:11318570

  13. Argentina

    Directory of Open Access Journals (Sweden)

    Hernan Galperin

    2004-01-01

    Full Text Available En este trabajo se analizan las bases sobre las que se está desarrollando el proceso de transición hacia la TV digital en Brasil y Argentina, y se discuten las posibilidades que la transición presenta para replantear la estructura de mercado y el modelo de regulación de la TV abierta en los países del Mercosur. La principal hipótesis es que la TV digital abre una oportunidad única para reformar el actual modelo de radiodifusión basado en la concesión de un número reducido de licencias a operadores de tipo generalista. Al multiplicar la capacidad de transmisión y facilitar el desarrollo de servicios interactivos tanto de entretenimiento como educativos y de información, la transición a la TV digital se ofrece como instrumento de política pública para alcanzar objetivos clave en materia de comunicación, como el pluralismo, la apertura del mercado y el achicamiento de la llamada brecha digital.

  14. Argentina

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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.

  17. 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

  18. 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

  19. Plan de comercialización Heliraid Patagonia

    OpenAIRE

    Mella, Natalia

    2012-01-01

    La Patagonia Argentina Austral, es considerada un icono a nivel mundial, reúne un conjunto de provincias y aspectos naturales únicos en el mundo1. La Cordillera de los Antes, sus paisajes, su geografía, y su historia. Muchos han sido los aventureros que dieron su vida por explorar y conocer esta zona. Y no todos vivieron para contarlo. Tradicionalmente, la Patagonia se caracterizaba por un escaso desarrollo comercial a raíz de los altos costos y su inaccesibilidad geográfica. Hoy, el desarrol...

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Comparación de condiciones de cultivo para el aislamiento y recuento simultáneo de levaduras de suelos de bosques nativos de Nothofagus spp. (Fagaceae de la Patagonia Argentina Comparison of culture conditions for isolation and count of soil yeasts from Nothofagus spp. (Fagaceae native forest of Argentinean Patagonia

    Directory of Open Access Journals (Sweden)

    María Cecilia Mestre

    2009-12-01

    Full Text Available Se compararon las condiciones de cultivo para aislar y contar levaduras del suelo de los bosques nativos de Nothofagus spp. en la Patagonia de Argentina. En este trabajo se propone la utilización de medios de cultivo adicionados con Rosa de Bengala 25 >g/mL y 200 >g/mL de Cloranfenicol. En estas condiciones se obtuvieron recuentos de levaduras que rondan 10³ UFC/g de suelo (aproximadamente 4% de la flora microbiana detectada. Se compararon los resultados de aislamientos por el método enriquecimiento-remoción utilizando las condiciones sin-enriquecimiento y con-enriquecimiento. Las levaduras aisladas fueron clasificadas en 7 grupos por características morfológicas y fisiológicas. Utilizando la técnica de MSP-PCR se obtuvieron 10 perfiles de bandas diferentes, que indicarían la presencia de al menos 10 especies en el suelo. La obtención de perfiles de bandas diferentes en los ensayos sin-enriquecimiento y con-enriquecimiento revelan la necesidad de utilizar estas dos formas de cultivo de manera complementaria para la recuperación de otras cepas, inhibidas o subestimadas por el cultivo directo sin-enriquecimiento.This research proposes the use of culture medium added with 25 >g/mL of Rose Bengal and 200 >g/mL of Chloramphenicol. Under these culture conditions the yeast counts were about 10³ CFU/g of soil (approximately 4% of detected microflora. Isolation with and without a previous enrichment step was compared. Isolated yeasts were classified into 7 groups based on morphological and physiological characteristics. 10 different banding patterns were observed using MSP-PCR technique, which indicate the presences of at least 10 species. Different banding pattern was observed between cultures with and without enrichment, this revealed the need of using both isolation techniques in a complementary way to recover strains inhibited or underestimated by direct non-enrichment methods.

  2. 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.

  3. Programa provincial de lectura del Chubut

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    Natalia Alejandra Alaniz

    2014-10-01

    Full Text Available En el marco del proyecto “Dispositivos pedagógicos en las dinámicas de lavida escolar en contexto de pobreza urbana” lo que se propuso investigar es la forma de implementación del Programa de Lectura de la provincia de Chubut. El mismo fue creado por Resolución Ministerial N° 1044/ 08, a partir de diversos trabajos que comenzaron en el año 2003 a través de la Ley de Educación 26. 026, y que posteriormente se incorporaron a nivel provincial mediante la Resolución N ° 174/12 para revalorizar las trayectorias escolares de cada niño/a. El programa consiste en poner el énfasis en el vínculo pedagógico mediante la adecuación de los espacios curriculares, de tal modo que se pueda lograr una articulación entre los diferentes niveles educativos, desde el nivel inicial al secundario. Articulando para ello recursos materiales y humanos que posibiliten el acompañamiento del proceso de enseñanza y aprendizaje de lectura.A partir de esto, el objetivo de este trabajo fue indagar cómo perciben los docentes de una escuela pública la implementación del Programa Provincial de Lectura, lo que implico utilizar metodologías y técnicas de investigación apropiadas para obtener las experiencias actuales en el territorio y en la cotidianidad de los propios actores escolares. Teniendo en consideración que el dispositivo pedagógico es una construcción histórica, que produce subjetividades, y por consiguiente formas de ver y entender el mundo.

  4. 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

    Directory of Open Access Journals (Sweden)

    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.

  5. La Patagonia galesa entre el tablero estatal y la idealización naturalista: aportes desde una perspectiva paisajística

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    Fernando Williams

    2014-11-01

    Full Text Available El presente artículo estudia la apropiación física y simbólica del territoriodesplegada desde la Colonia Chubut, primera colonia agrícola de la Patagonia,fundada en 1865 por un grupo de galeses. El interés del trabajo es la gestióndel territorio puesta en práctica por las instituciones formadas en el valledel Chubut por los colonos, en particular, por el “Municipio del Chubut” consede en Gaiman. Se han problematizado las coordenadas desde las que eraconcebido lo político y lo público y se ha incorporado al análisis un conjuntode registros que dan cuenta de una gestión informada no sólo por una legislaciónsino también por las prácticas y las miradas sobre ese territorio.

  6. DE GESTAS, DE SALVAJES Y DE MÁRTIRES. EL RELATO MAESTRO SOBRE EL FUERTE SAN JOSÉ RECONSIDERADO DESDE LA ARQUEOLOGÍA HISTÓRICA (PENÍNSULA VALDÉS, PCIA. DE CHUBUT, SIGLO XVIII / Savages, Epics and Martyrs. The Master Narrative about San Jose Fort reconside

    Directory of Open Access Journals (Sweden)

    Marcia Bianchi Villelli

    2015-06-01

    Full Text Available Desde inicios del siglo XX hasta el presente, la historiografía tradicional argentina se ha ocupado de estudiar la colonización española de costa patagónica de fines del siglo XVIII. La perspectiva desarrollada hasta 1980 se vinculaba principalmente a ámbitos conservadores de la historia que generaron una imagen fuertemente eurocéntrica y colonialista tanto del proceso de poblamiento como de cada uno de los tres asentamientos instalados sobre la costa patagónica entre 1779 y 1780 (el Fuerte Nuestra Señora del Carmen -Carmen de Patagones, Pcia. de Buenos Aires-, la Nueva Colonia y Fuerte de Floridablanca -Puerto San Julián, Pcia. de Santa Cruz- y el Fuerte San José -Península Valdés, Pcia. de Chubut.A partir de nuevas investigaciones realizadas en el Fuerte San José, el presente trabajo discutelas aproximaciones históricas tradicionales al mismo. Desde una perspectiva descolonial, se busca mostrar cómo el relato maestro historiográfico es solidario con la construcción del estado nación argentino, apoyándose en una mirada retrospectiva para legitimar su profundidad temporal y extensión espacial. De este modo, proponemos desde la arqueología histórica exponer la materialidad de nuevas tramas de sentidos para comprender proceso colonial en Patagonia, visibilizando otros espacios, actores, procesos y materialidades que habían quedado desdibujados en el relato maestro de la historiografía provincial y nacional.   Abstract  From the beginnings of the twentieth century up to present day, Argentinian traditional historiography has studied the late eighteenth century Spanish colonization of the Patagonian coast. The viewpoint developed until 1980 was mainly linked to conservative environmentsof historythat generated a strong Eurocentric and colonialist image of both, the process of settlement andof each of the three installed settlements on the Patagonian coast between 1779 and 1780 (Nuestra Señora del Carmen Fort -Carmen de

  7. 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

  8. Patagonia: nature and territories

    Directory of Open Access Journals (Sweden)

    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.

  9. Nueva edad de la base del grupo Chubut en la mena uranífera Cerro Solo, provincia del Chubut

    Directory of Open Access Journals (Sweden)

    Nilda Marveggio

    2013-09-01

    Full Text Available En este trabajo se analizan las características litológicas de la roca hospedante de la mineralización de uranio del yacimiento Cerro Solo, que corresponde al miembro inferior de la Formación Los Adobes, unidad basal del Grupo Chubut en su sector norte. Se analiza la asociación de polen angiospérmico de allí recuperada, y en base a ese análisis, se establece una edad albiana temprana para la asociación polínica, que determina una edad más joven que la considerada hasta el momento para el inicio de la depositación de las sedimentitas del Grupo Chubut en el depocentro del yacimiento Cerro Solo.

  10. Telón de fondo: Paisajes de desierto y alteridad en la fotografía de la Patagonia (1880-1900 Backdrop: Desert and Alterity Landscapes in the Photography of Patagonia (1880-1900

    Directory of Open Access Journals (Sweden)

    Carlos Masotta

    2009-12-01

    Full Text Available El paisaje patagónico construido por la fotografía del período 1880-1900 fue un marco en donde se llevó a cabo el ingreso civilizatorio. Luego de una caracterización general del problema (el paisaje desierto como «escenificación de ausencia» en torno a los primeros álbumes de Estado sobre la región, centro el análisis de este artículo en dos obras que describieron el Territorio de Chubut: Viaje a la Patagonia Austral (1886 del Coronel Luis Fontana y la Excursión a la Patagonia y a los Andes de Aarón Anchorena (1902. Entre ellas puede observarse la articulación de una mirada militar y civil donde el paisaje fotográfico del desierto se involucra en la toma material y simbólica del territorio como un escenario donde se «naturaliza» la actuación de un ingreso civilizatorio y la desaparición de los pueblos indígenas.The Patagonian landscape built up by photography during the 1880-1900 periods was the framework in which the civilizing entrance took action. After a general description of the problem (the deserted landscape as the staging of absence about the first State's albums on the region, I focus the analysis on two works describing the Territory of Chubut: Viaje a la Patagonia Austral (Trip to Southern Patagonia by Coronel Luis Fontana (1886 and Excursion a la Patagonia y a los Andes (Tour to Patagonia and the Andes, de Aaron Anchorena (1902. The articulation of a military and civil glance can be observed between them, where the photographic landscape of the desert is involved in the material and symbolic shot of the territory as a stage where the acting of a civilizing entrance and the disappearance of the indigenous peoples is naturalized.

  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. Estado actual del conocimiento del orden Odonata en la Patagonia Current knowledge of Patagonian Odonata

    OpenAIRE

    Javier Muzón

    2009-01-01

    El orden Odonata se encuentra representado en la Patagonia por 36 especies, reunidas en nueve familias y 18 géneros. El nivel de endemismo de esta taxocoenosis es alto, aproximadamente el 60% de las especies y casi el 40% de los géneros endémicos. La riqueza específica en la Patagonia decrece de Oeste a Este y de Norte a Sur, las áreas de mayor riqueza resultan ser las cordilleras de Nahuel Buta (Chile) y de los Andes entre 38° y 41° S, y la meseta de Somuncurá (Argentina) en la estepa. Se br...

  13. Patagonia, naturaleza y territorios

    OpenAIRE

    Schweitzer, Alejandro Fabián

    2014-01-01

    La Patagonia es desde fines del siglo XIX espacio de provisión de recursos de la naturaleza. Las políticas nacionales y provinciales para la región llevaron a significativos procesos de desarrollo geográfico desigual, con espacios en general muy poco poblados. Actualmente pervive y se acentúa el modelo primario-exportador de la mano del neoextractivismo, con el Estado buscando participar en el reparto de la renta por la explotación del subsuelo, suelo y litoral marítimo. En el articulo se ana...

  14. The first geological mapof Patagonia

    Directory of Open Access Journals (Sweden)

    Eduardo O. Zappettini

    2009-04-01

    Full Text Available 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.

  15. Corrales de piedra, campos abiertos y pampas de camaruco: Memorias de relacionalidad en la meseta central de Chubut Stone yards, open fields and sacred places: Memories of relatedness in the Chubut´s central plateau

    Directory of Open Access Journals (Sweden)

    Ana Ramos

    2008-12-01

    Full Text Available La "cuestión indígena" como política de estado en Argentina ha estado acompañada por la elaboración académica de mapas étnicos. Las definiciones hegemónicas de estas entidades han presupuesto generalmente algún elemento "esencial" como, por ejemplo, fenotipos, uso de una lengua, o la aglutinación en torno a linajes consanguíneos. A partir de las reformulaciones de las teorías del parentesco desde el modelo heurístico de las sociedades de casas y las teorías sobre la relacionalidad proponemos una aproximación a la memoria social como marco alternativo de interpretación histórica. Esta contempla las prácticas sociales del parentesco y la objetivación de la continuidad de los grupos de pertenencia en las políticas y lugares de la memoria -corrales de piedra, actividades productivas y pampas de camaruco- en la región de la "meseta" de Chubut. Dichas relaciones con el espacio físico cuestionan tanto las definiciones académicas tradicionales de parentesco y de cacicazgo como las clasificaciones étnicas-nacionales.The "Indigenous issue" as a state policy in Argentina has been accompanied by an academic production of ethnic maps. Hegemonic definitions of these entities used to presume some "essential" elements like the phenotype, the use of language or consanguineous lineage membership. Based on the reformulation of kinship theory, which came from the heuristic model of houses and relatedness theory, we propose an approach to social memory as an alternative framework for historical interpretation. This includes kinship social practices as well as the materialization of group membership's continuity in policies and places of memory -such as stone yards, productive activities, open fields and sacred places- in the Chubut central plateau. Finally, we argue that regarding a physical space, these relations question not only the ethnic-national classifications but also the traditional academic definitions of kinship and chieftaincy.

  16. Estratigrafía y petrología del sector noreste de sierra de Apas. Provincia del Chubut Stratigraphy and petrology of the Northeastern sector of Sierra de Apas. Chubut Province

    Directory of Open Access Journals (Sweden)

    M. Remesal

    2004-12-01

    Full Text Available La sierra de Apas, ubicada entre las provincias de Rio Negro y Chubut, forma parte del magmatismo de intraplaca emplazado durante el Paleogeno-Neógeno en el norte de la Patagonia extrandina. En el sector noreste se ha definido una estratigrafía integrada por: traquitas oscuras, flujos piroclásticos, traquitas claras, domos riolíticos y basaltos porfíricos y afíricos. Las traquitas oscuras, son relativamente más antiguas, tienen bajo porcentaje de fenocristales, y clasifican como traquitas- benmoreítas. Las traquitas claras son porfíricas, y clasifican como comenditas. Su ubicación estratigráfica es confirmada por una edad K/Ar de 19 ± 2 Ma. Los flujos piroclásticos son predominantemente vítreos, cubren a las traquitas oscuras y tienen composiciones traquiandesíticas. La petrografía y geoquímica establecen una estrecha relación con las traquitas claras. El único cuerpo dómico en el área es el cerro Colorado, cuya composición corresponde a una riolita peralcalina ó comendita; una edad K/Ar de 24 ± 1 Ma establece por primera vez su relación temporal. La unidad efusiva más joven corresponde a lavas basálticas, agrupadas en afíricas y porfíricas. Se propone designar a las primeras como basaltos olivínicos transicionales en tanto que los basaltos porfíricos se subdividen en basaltos olivínicos alcalinos y hawaiitas. Los datos estratigráficos y geoquímicos sugieren que la asociación volcánica estudiada es el resultado de al menos dos etapas evolutivas. Una de ellas incluye los basaltos, traquitas claras, flujos claros y comenditas que muestran un patrón de cristalización fraccionada. Las traquitas oscuras, más viejas, corresponderían a otro estadio evolutivo.The volcanic building of Sierra de Apas (located on the limit between the Rio Negro and Chubut provinces is part of the Paleogene-Neogene intraplate magmatism of the northern Extrandean Patagonia. This contribution is focused on the northeastern of the Sierra

  17. Angelaíta en la paragénesis del distrito Los Manantiales, provincia del Chubut: Una nueva especie mineral

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    M.K. de Brodtkorb

    2004-12-01

    Full Text Available Angelaíta, Cu2AgPbBiS2 , una nueva especie mineral, fue localizada en la mina Ángela, mineralización de tipo IS del distrito Los Manantiales, Chubut, Argentina. La paragénesis incluye esfalerita, pirita, calcopirita, galena y en menor cantidad arsenopirita, betekhtinita, bornita, matildita, oro, plata, electrum, telurio, cervelleíta y hematita. La galena presenta numerosas inclusiones de angelaíta, aikinita, wittichenita y miharaíta. Esta paragénesis se presenta en vetas asociada a diferentes rocas volcánicas de la Formación Lonco Trapial de edad jurásica. La composición química de angelaíta fue obtenida con una microsonda electrónica. Se presenta en granos anhedrales de 10-100mm, es de color gris verdoso, moderadamente pleocroica y anisótropa.

  18. Estado actual del conocimiento del orden Odonata en la Patagonia Current knowledge of Patagonian Odonata

    Directory of Open Access Journals (Sweden)

    Javier Muzón

    2009-06-01

    Full Text Available El orden Odonata se encuentra representado en la Patagonia por 36 especies, reunidas en nueve familias y 18 géneros. El nivel de endemismo de esta taxocoenosis es alto, aproximadamente el 60% de las especies y casi el 40% de los géneros endémicos. La riqueza específica en la Patagonia decrece de Oeste a Este y de Norte a Sur, las áreas de mayor riqueza resultan ser las cordilleras de Nahuel Buta (Chile y de los Andes entre 38° y 41° S, y la meseta de Somuncurá (Argentina en la estepa. Se brinda una actualización del estado de conocimiento y un análisis de los principales patrones de distribución.The Odonata order is represented in Patagonia by 36 species belonging to nine families and 18 genera. The endemicity level is high being approximately 60% of the species and 40% of genera endemic. The specific richness in Patagonia decreases from West to East and from North to South, being Nahuel Buta (Chile and Andes mountains between 38° and 41° S on the forest area, and the Somuncurá plateau (Argentina on the steppe the richest areas. An update of its records and an analysis of the main distribution patterns are provided in this paper.

  19. 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.

  20. El “Hombre Fósil de Mata Molle” (Neuquén, Argentina: cronología y variación craneofacial en el contexto de las poblaciones de Patagonia y Sudamérica

    Directory of Open Access Journals (Sweden)

    Gordón, Florencia

    2013-12-01

    Full Text Available Los restos óseos del sitio Mata Molle (Provincia de Neuquén han constituido una importante referencia en los estudios sobre el poblamiento de la región Patagónica debido a la elevada antigüedad y las características morfológicas singulares que le fueron asignadas. En este trabajo se presentan los resultados del análisis de la morfología craneofacial en el contexto de los restos humanos tempranos de Sudamérica, junto con la primera datación radiocarbónica obtenida directamente sobre material óseo. Por medio del análisis osteológico se determinó que el entierro corresponde a dos individuos adultos, uno masculino (Ind. 1 y otro femenino (Ind. 2. El Ind. 1 presentó un elevado grado de desgaste dental y marcadores de estrés músculo esqueletal en el radio derecho y huesos de los miembros inferiores, compatibles con elevados niveles de actividad física. La estatura y masa corporal estimadas se encuentran dentro del rango observado en muestras del Norte de Patagonia de similar cronología. La morfología craneana del Ind. 1 exhibe gran similitud con la de las muestras más tempranas de Sudamérica y de la región Pampeana y se caracteriza por una mayor longitud anteroposterior y una reducción en el ancho y la altura. Sin embargo, la datación radiocarbónica indica que el entierro de Mata Molle corresponde al Holoceno tardío inicial (3270±46 años AP y no al Holoceno medio o temprano como había sido señalado previamente. Los valores de d13C y de d15N se encuentran dentro de los rangos esperados para dietas terrestres.

  1. Petrogénesis de los thundereggs en domos riolíticos del centro del Chubut, Patagonia Petrogenesis of thundereggs in Eocene rhyolite domes of central Chubut, Patagonia

    Directory of Open Access Journals (Sweden)

    E. Aragón

    2006-09-01

    Full Text Available Se describen los thundereggs que se encuentran en domos vitrofíricos de la caldera de Piedra Parada. Tanto las características geológicas, petrológicas como geoquímicas sugieren que estos crecen a partir de gotas de líquidos inmiscibles que se desvitrificaron como esferulitas de anortoclasa. La expansión de la fase vapor segregada al desvitrificarse las gotas inmiscibles, rompieron las esferulitas y desarrollaron grandes vesículas tapizadas por los pedazos rotos de la esferulita. El inmediato enfriamiento del resto del magma dio lugar a la formación de un domo vítreo con textura perlítica. Posteriormente, agua a baja temperatura lixivió al vidrio esferulítico y rellenó las cavidades de las vesículas y esferulitas con ópalo y/o calcedonia.Thundereggs at the glass domes of Piedra Parada Caldera are described. Their geological, petrological and geochemical characteristics suggest growth from immiscible liquid drops that devitrified as anorthoclase spherulites. The expansion of the segregated vapor phase of the devitrified immiscible drops broke the spherulites and made large vesicles lined with the broken pieces of the spherulite. Further cooling of the rest of the magma yielded a glass dome with perlitic texture. Low temperature water lixiviated the perlitic glass and spherulites, filling the cavities within the vesicles and broken spherulite with opal and/or chalcedony.

  2. Un género nuevo de Eriococcidae (Hemiptera: Coccoidea de la Argentina A new genus of Eriococcidae (Hemiptera: Coccoidea from Argentina

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    Patricia González

    2008-12-01

    Full Text Available Se describe un género nuevo, Poliloculus gen. nov. Se brinda una clave de los géneros de Eriococcidae de la Argentina. Se describe e ilustra la hembra adulta de Poliloculus stipae sp. nov., encontrada sobre Stipa sp. en la Patagonia.Poliloculus gen. nov. is described. A key to the genera of Eriococcidae of Argentina is given. The adult female of Poliloculus stipae sp. nov. collected in Stipa sp. in the Patagonia is described and illustrated

  3. Petrogénesis de los thundereggs en domos riolíticos del centro del Chubut, Patagonia

    Directory of Open Access Journals (Sweden)

    E. Aragón

    2006-09-01

    Full Text Available Se describen los thundereggs que se encuentran en domos vitrofíricos de la caldera de Piedra Parada. Tanto las características geológicas, petrológicas como geoquímicas sugieren que estos crecen a partir de gotas de líquidos inmiscibles que se desvitrificaron como esferulitas de anortoclasa. La expansión de la fase vapor segregada al desvitrificarse las gotas inmiscibles, rompieron las esferulitas y desarrollaron grandes vesículas tapizadas por los pedazos rotos de la esferulita. El inmediato enfriamiento del resto del magma dio lugar a la formación de un domo vítreo con textura perlítica. Posteriormente, agua a baja temperatura lixivió al vidrio esferulítico y rellenó las cavidades de las vesículas y esferulitas con ópalo y/o calcedonia.

  4. Photovoltaic systems in Patagonia

    Energy Technology Data Exchange (ETDEWEB)

    Lawand, T.A. [McGill Univ., Ste. Anne de Bellevue, PQ (Canada). Brace Research Inst., Macdonald Coll; Rapallini, A. [MR Consultores, Buenos Aires, (Argentina); Pedro, G. [Ente Provincial de Energia del Neuquen, Neuquen, (Argentina)

    1998-05-01

    The feasibility of using of solar photovoltaic (PV) systems in the remote cold areas of the Neuquen province in Argentina was discussed. A program was developed by the local public utility to provide schools with electricity using photovoltaic panels. The PV systems have replaced expensive diesel generators which had become unreliable. In the first phase of the program, 27 schools were electrified using photovoltaic panels, battery storage systems and simple control panels. A review of the performance of the system components under the harsh climatic conditions of the region was discussed. The program has been expanded to include about 50 family systems. Another 150 are projected for the near future. 3 refs., 2 figs., 3 tabs.

  5. Latest Pleistocene and Holocene Glacier Fluctuations in southernmost Patagonia

    Science.gov (United States)

    Menounos, B.; Maurer, M.; Clague, J. J.; osborn, G.; Ponce, F.; Davis, P. T.; Rabassa, J.; Coronato, A.; Marr, R.

    2011-12-01

    Summer insolation has been proposed to explain long-term glacier fluctuations during the Holocene. If correct, the record of glacier fluctuations at high latitudes in the Southern Hemisphere should differ from that in the Northern Hemisphere. Testing this insolation hypothesis has been hampered by dating uncertainties of many Holocene glacier chronologies from Patagonia. We report on our ongoing research aimed at developing a regional glacier chronology at the southern end of the Andes north and west of Ushuaia, Argentina. We have found evidence for an advance of cirque glaciers at the end of the Pleistocene; one or locally two closely spaced moraines extend up to 2 km beyond Little Ice Age moraines. Radiocarbon dating of terrestrial macrofossils recovered from basal sediments behind two of these moraines yielded ages of 10,320 ± 25 and 10,330 ± 30 14C yr BP. These moraines may record glacier advances coeval with the Antarctic Cold Reversal; surface exposure dating of these moraines is currently in progress to test this hypothesis. We find no evidence of Holocene moraines older than 6800 14C yr BP, based on the distribution of Hudson tephra of that age. At some sites, there is evidence for an early Neoglacial advance of glaciers slightly beyond (Ushuaia. Ten radiocarbon ages on these wood mats range in age from 3510 ± 15 to 135 ± 15 14C yr BP. The mats decrease in age up-section; many overlap with published age ranges for Neoglacial advances in western Canada. Taken together, these data: a) do not support the summer insolation hypothesis for Holocene glacier fluctuations in southernmost Patagonia; b) confirm paleobotanical evidence for a warm, dry early Holocene; and c) suggest that many Neoglacial advances in southernmost Patagonia and western North America were synchronous.

  6. 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

  7. Phytoseiid mites (Acari: Phytoseiidae) from Patagonia and Tierra del Fuego.

    Science.gov (United States)

    Ferragut, Francisco; Navia, Denise

    2015-01-01

    Predatory phytoseiid mites have been intensively studied and surveyed in the last decades because of their economic importance as biocontrol agents of agricultural pests. However, many regions of the world remain unexplored and the diversity of the family worldwide is still fragmentary. Up to date no phytoseiid species have been collected in the southernmost part of the Earth down to latitude 45º S. In this study Phytoseiidae were sampled from native vegetation in southern Argentina and Chile in the regions of Patagonia and Tierra del Fuego Island. Thirteen species were collected, five of which were previously described and eight, Chileseius australis n. sp., Neoseiulus mapuche n. sp., Typhlodromips valdivianus n. sp., T. fissuratus n. sp., Amblyseius grandiporus n. sp., A. caliginosus n. sp., Typhlodromus (Anthoseius) anomalos n. sp. and Metaseiulus parabrevicollis n. sp. are proposed as new to science and are described and diagnosed. PMID:26250248

  8. Estratigrafía y petrología del sector noreste de sierra de Apas. Provincia del Chubut

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    M. Remesal

    2004-12-01

    Full Text Available La sierra de Apas, ubicada entre las provincias de Rio Negro y Chubut, forma parte del magmatismo de intraplaca emplazado durante el Paleogeno-Neógeno en el norte de la Patagonia extrandina. En el sector noreste se ha definido una estratigrafía integrada por: traquitas oscuras, flujos piroclásticos, traquitas claras, domos riolíticos y basaltos porfíricos y afíricos. Las traquitas oscuras, son relativamente más antiguas, tienen bajo porcentaje de fenocristales, y clasifican como traquitas- benmoreítas. Las traquitas claras son porfíricas, y clasifican como comenditas. Su ubicación estratigráfica es confirmada por una edad K/Ar de 19 ± 2 Ma. Los flujos piroclásticos son predominantemente vítreos, cubren a las traquitas oscuras y tienen composiciones traquiandesíticas. La petrografía y geoquímica establecen una estrecha relación con las traquitas claras. El único cuerpo dómico en el área es el cerro Colorado, cuya composición corresponde a una riolita peralcalina ó comendita; una edad K/Ar de 24 ± 1 Ma establece por primera vez su relación temporal. La unidad efusiva más joven corresponde a lavas basálticas, agrupadas en afíricas y porfíricas. Se propone designar a las primeras como basaltos olivínicos transicionales en tanto que los basaltos porfíricos se subdividen en basaltos olivínicos alcalinos y hawaiitas. Los datos estratigráficos y geoquímicos sugieren que la asociación volcánica estudiada es el resultado de al menos dos etapas evolutivas. Una de ellas incluye los basaltos, traquitas claras, flujos claros y comenditas que muestran un patrón de cristalización fraccionada. Las traquitas oscuras, más viejas, corresponderían a otro estadio evolutivo.

  9. Migración y movilidad mapuche entre Araucanía y nor Patagonia

    OpenAIRE

    Hans Gunderman; Héctor González; Larisa de Ruyt

    2009-01-01

    El artículo presenta antecedentes acerca de la migración y movilidad campesina e indígena mapuche desde las regiones de Araucanía, Los Ríos y Los Lagos a la Patagonia argentina, especialmente al Neuquén y Río Negro, durante la segunda mitad del siglo XX. Se establece lo anterior como parte de un proceso mucho más amplio de redistribución espacial que incluye el centro de Chile, Magallanes y la Patagonia trasandina. Se describe su condición de migración económica y los cambios que en ella han ...

  10. Gondwanide continental collision and the origin of Patagonia

    Science.gov (United States)

    Pankhurst, R. J.; Rapela, C. W.; Fanning, C. M.; Má; rquez, M.

    2006-06-01

    A review of the post-Cambrian igneous, structural and metamorphic history of Patagonia, largely revealed by a five-year programme of U-Pb zircon dating (32 samples), geochemical and isotope analysis, results in a new Late Palaeozoic collision model as the probable cause of the Gondwanide fold belts of South America and South Africa. In the northeastern part of the North Patagonian Massif, Cambro-Ordovician metasediments with a Gondwana provenance are intruded by Mid Ordovician granites analogous to those of the Famatinian arc of NW Argentina; this area is interpreted as Gondwana continental crust at least from Devonian times, probably underlain by Neoproterozoic crystalline basement affected by both Pampean and Famatinian events, with a Cambrian rifting episode previously identified in the basement of the Sierra de la Ventana. In the Devonian (following collision of the Argentine Precordillera terrane to the north), the site of magmatism jumped to the western and southwestern margins of the North Patagonian Massif, although as yet the tectonics of this magmatic event are poorly constrained. This was followed by Early Carboniferous I-type granites representing a subduction-related magmatic are and Mid Carboniferous S-type granites representing crustal anatexis. The disposition of these rocks implies that the North Patagonian Massif was in the upper plate, with northeasterly subduction beneath Gondwana prior to the collision of a southern landmass represented by the Deseado Massif and its probable extension in southeastern Patagonia. This 'Deseado terrane' may have originally rifted off from a similar position during the Cambrian episode. Intense metamorphism and granite emplacement in the upper plate continued into the Early Permian. Known aspects of Late Palaeozoic sedimentation, metamorphism, and deformation in the Sierra de la Ventana and adjacent Cape Fold Belt of South Africa are encompassed within this model. It is also compatible with modern geophysical and

  11. Caracterización geológica del skarn "El Abuelo" Alto Río Senguerr, Chubut

    Directory of Open Access Journals (Sweden)

    M.E. Lanfranchini

    2004-12-01

    Full Text Available El skarn "El Abuelo" está situado en el extremo sudoccidental de la Provincia del Chubut, República Argentina. Se desarrolla en un ambiente tectónico de arco magmático, en corteza continental. Está emplazado en sedimentitas silicoclásticas con intercalaciones carbonáticas y se vincula a cuerpos intrusivos riodacíticos, conjunto atribuido al Cretácico inferior. En esta manifestación se reconocieron anomalías en elementos metalíferos (Fe, Cu, Pb, Zn, Ag que le confieren interés como guía para la exploración de recursos minerales en esta región. La presente contribución tiene por finalidad tipificar al skarn a través de una caracterización geológica y mineralógica. La asociación paragenética de minerales reconocidos permitió identificar dos episodios: uno metasomático y otro hidrotermal, ambos desarrollados en las sedimentitas (exoskarn. El primero fue originado por fluidos de derivación magmática, que provocaron la formación de minerales calcosilicáticos. Posteriormente la incorporación de agua en el sistema facilitó el desarrollo de minerales hidratados, retrogradando parcialmente al skarn, proceso que fue seguido por la depositación de hematita, magnetita y sulfuros, acompañados de sílice. La asociación de minerales calcosilicáticos, junto a la variación en la composición química de piroxenos y granates y la mineralización identificada, permiten tipificar al skarn "El Abuelo" como cálcico, con hierro como metal dominante.

  12. Caracterización geológica del skarn "El Abuelo" Alto Río Senguerr, Chubut Geological characterization of "El Abuelo" skarn deposit, Alto Rio Senguerr, Chubut

    Directory of Open Access Journals (Sweden)

    M.E. Lanfranchini

    2004-12-01

    Full Text Available El skarn "El Abuelo" está situado en el extremo sudoccidental de la Provincia del Chubut, República Argentina. Se desarrolla en un ambiente tectónico de arco magmático, en corteza continental. Está emplazado en sedimentitas silicoclásticas con intercalaciones carbonáticas y se vincula a cuerpos intrusivos riodacíticos, conjunto atribuido al Cretácico inferior. En esta manifestación se reconocieron anomalías en elementos metalíferos (Fe, Cu, Pb, Zn, Ag que le confieren interés como guía para la exploración de recursos minerales en esta región. La presente contribución tiene por finalidad tipificar al skarn a través de una caracterización geológica y mineralógica. La asociación paragenética de minerales reconocidos permitió identificar dos episodios: uno metasomático y otro hidrotermal, ambos desarrollados en las sedimentitas (exoskarn. El primero fue originado por fluidos de derivación magmática, que provocaron la formación de minerales calcosilicáticos. Posteriormente la incorporación de agua en el sistema facilitó el desarrollo de minerales hidratados, retrogradando parcialmente al skarn, proceso que fue seguido por la depositación de hematita, magnetita y sulfuros, acompañados de sílice. La asociación de minerales calcosilicáticos, junto a la variación en la composición química de piroxenos y granates y la mineralización identificada, permiten tipificar al skarn "El Abuelo" como cálcico, con hierro como metal dominante."El Abuelo" skarn deposit is located in southwest Chubut province. It was formed in a magmatic arc tectonic environment, developed in continental crust. The skarn is hosted in low cretaceous silicoclastic sands interbedded with limestones, and it is related to small rhyodacitic sub-volcanic bodies. Anomalous contents of metals (Fe, Cu, Pb, Zn, Ag provide an interesting exploration guide. This paper is devoted to give a geological and a mineralogical characterization of the skarn, in order

  13. Estado de conocimiento del orden Ephemeroptera en la Patagonia Current knowledge of Patagonian Ephemeroptera

    Directory of Open Access Journals (Sweden)

    Pablo Pessacq

    2009-06-01

    Full Text Available El conocimiento actual del orden Ephemeroptera en la Patagonia se debe en gran parte a la labor original y compilatoria de M.L. Pescador, W.L. Peters y E. Domínguez, llevada a cabo en la década del 80 del siglo pasado. Se suman a ésta, importantes contribuciones que han conducido a un adecuado conocimiento del grupo en la cordillera norte y centro de la Patagonia, aunque menor en la zona austral de esta región (Santa Cruz y Tierra del Fuego y las áreas de estepa. Merced al trabajo de campo realizado en 80 sitios de muestreo relevados en el marco del "Darwin Initiative Project" en el Parque Nacional Nahuel Huapi, se incluyen aquí nuevos registros para la Argentina (Hapsiphlebia anastomosis Demoulin, la región Andina (Apobaetis Day y la provincia de Río Negro (Chaquihua bullocki (Navás, Andesiops ardua (Lugo-Ortíz & McCafferty, Murphyella needhami Lestage y Dactylophlebia carnulenta Pescador & Peters. Con estos registros, la riqueza de Ephemeroptera de la Patagonia alcanza 43 especies y 24 géneros, de las cuales 33 (en 20 géneros se conocen para la Argentina.The current knowledge of the Patagonian Ephemeroptera is due to the original and compiling work by M.L. Pescador, W.L. Peters and E. Domínguez during last Century's 80´s . Besides, other previous publications exist that contributed to achieve a reasonable knowledge of its taxonomy for the norhtern and central Patagonian Andes, though poor for the southernmost mountain areas (Santa Cruz and Tierra del Fuego provinces and the steppe. From the field work carried in 80 collecting sites during the development of the "Darwin Initiative Project" in the Nahuel Huapi Nacional Park, some species are recorded for the first time in Argentina (Hapsiphlebia anastomosis Demoulin, the Andean region (Apobaetis Day and the province of Río Negro (Chaquihua bullock (Navás, Andesiops ardua (Lugo-Ortíz & McCafferty, Murphyella needhami Lestage, Dactylophlebia carnulenta Pescador & Peters. With

  14. Un género nuevo de Eriococcidae (Hemiptera: Coccoidea de la Argentina

    Directory of Open Access Journals (Sweden)

    Patricia GONZÁLEZ

    2008-01-01

    Full Text Available Se describe un género nuevo, Poliloculus gen. nov. Se brinda una clave de los géneros de Eriococcidae de la Argentina. Se describe e ilustra la hembra adulta de Poliloculus stipae sp. nov., encontrada sobre Stipa sp. en la Patagonia.

  15. In situ impact of solar ultraviolet radiation on photosynthesis and DNA in temperate marine phytoplankton

    NARCIS (Netherlands)

    Helbling, E.W; Buma, A.G.J.; de Boer, M.K.; Villafane, V

    2001-01-01

    In situ experiments were conducted at various depths in the water column to determine the impact of solar UV radiation (280 to 400 nm) upon photosynthesis and DNA of natural phytoplankton assemblages from mid-latitudes of Patagonia (Bahia Bustamante, Chubut, Argentina; 45 degreesS, 66.5 degreesW). T

  16. The Genus Austroleptis from South Chile and Patagonia (Diptera, Rhagionidae)

    OpenAIRE

    NAGATOMI, Akira; NAGATOMI, Hisako; ナガトミ, アキラ; ナガトミ, ヒサコ; 永冨, 昭; 永冨, 尚子

    1988-01-01

    The genus Austroleptis from South Chile and Patagonia is revised and three new species are added. So, there are eight known species, five of which are from South Chile and Patagonia and three from Australia and Tasmania.

  17. El caso del Outburst Flood histórico de la laguna Derrumbe, Cholila, Chubut: Colapso de dique Morénico en la Cordillera Norpatagónica The historic outburst flood of the laguna Derrumbe, Cholila, Chubut: Fast glacier retreat and moraine dam failure in North Patagonian Cordillera

    Directory of Open Access Journals (Sweden)

    Bruno Colavitto

    2012-09-01

    Full Text Available La laguna Derrumbe es un cuerpo de agua ubicado en los Andes Norpatagónicos en la provincia de Chubut, Argentina. Está contenida en un circo glaciario y endicada por una morena frontal del glaciar homónimo. A través del reconocimiento de campo se pudo describir a esta laguna y a un importante depósito rocoso que se halla aguas abajo de la misma, interpretado como un depósito de outburst flood. Estos depósitos son generados por procesos de alta energía relacionados con la rotura de un dique natural, en este caso un dique morénico. El estudio realizado permitió concluir que la morena frontal del glaciar Derrumbe sufrió una rotura parcial en tiempos históricos, desatando así una inundación súbita aguas abajo de la laguna, a través del valle del río Tigre, en la localidad de Cholila. En este trabajo se analizaron las posibles causas que dieron lugar a la rotura, la cual probablemente sea producto del rápido retroceso que el glaciar experimentó durante la década del ´50 y principios del ´60. Retroceso comparable con el ocurrido en muchos de los cuerpos glaciares de los Andes Patagónicos durante el último siglo.The Laguna Derrumbe is a body of water located in the North Patagonian Andes, in Chubut province, Argentina. This lake is contained in a glacial cirque and dammed by the terminal moraine of the namesake glacier. Through field survey it was possible to describe this lake and an important rocky deposit downstream of it, which is interpreted as an outburst flood deposit. These deposits are generated by high-energy processes related to the failure of a natural dam, in this case a moraine dam. The study made allowed to conclude that the frontal moraine of the Derrumbe glacier suffered a partial rupture in historic times, unleashing a flash flood downstream to the lake, through the Tigre river valley in the town of Cholila. In this work the possible causes that led to the failure are discussed, concluding that the main cause

  18. Migración y movilidad mapuche entre Araucanía y nor Patagonia

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    Hans Gunderman

    2009-12-01

    Full Text Available El artículo presenta antecedentes acerca de la migración y movilidad campesina e indígena mapuche desde las regiones de Araucanía, Los Ríos y Los Lagos a la Patagonia argentina, especialmente al Neuquén y Río Negro, durante la segunda mitad del siglo XX. Se establece lo anterior como parte de un proceso mucho más amplio de redistribución espacial que incluye el centro de Chile, Magallanes y la Patagonia trasandina. Se describe su condición de migración económica y los cambios que en ella han tenido lugar, tanto por los vaivenes de las economías y las relaciones entre Chile y Argentina, como por la formación de redes sociales de parentesco y comunalidad entre áreas de origen y de destino. Lo anterior se pone en relación con la pauta de integración regional que el pueblo mapuche ha construido en la época moderna y las relaciones translocalizadas que siguen favoreciendo una notable dinámica movilidad, vinculando sus segmentos rurales y urbanos, peri o semi urbanos.This article offers background information on the migration and mobility of peasants and Mapuche people from the Araucanía, Los Rios and Los Lagos regions to the Argentinian Patagonia, especially to Neuquén and Río Negro, during the second half of the 20th century. This event is part of a larger process of spatial redistribution that includes central Chile, Magallanes and the Patagonia region across the Andes. We describe this economic migration as well as the changes that have taken place because of the oscillation of economies and the relations between Chile and Argentina, or because of the formation of kinship and community social nets between the areas of origin and destination. This idea is related to the regional integration pattern that the Mapuche people have created in the modern era as well as to the translocated relationships that keep favoring mobility between rural, urban and semi urban components.

  19. 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 (18.000Precambrian basement. The geographic trend in lead isotope compositions of both galena and whole rocks indicates a crustal contribution which increases eastwards, also reflected in the strontium-neodymium isotope systematics of the host lavas. Finally, due to the lack of precise age determinations for the central Patagonian polymetallic deposits, a potential link with Andean porphyry copper systems remains an open question.

  20. Environmental Determinants of the Distribution and Abundance of the Ants, Lasiophanes picinus and L. valdiviensis, in Argentina

    OpenAIRE

    Fergnani, Paula; Sackmann, Paula; Cuezzo, Fabiana

    2008-01-01

    The distribution and abundance variation of the terrestrial ants, Lasiophanes picinus and Lasiophanes valdiviensis Emery (Formicinae: Lasiini), which are endemic in Patagonia (Argentina and Chile), are described and a set of environmental factors are examined to explain the observed patterns. Ants were collected using 450 pitfall traps arranged in 50, 100 m2 grid plots each with nine traps within a roughly 150 × 150 km area representative of the subantartic-patagonian transition of Argentina....

  1. Hydrogen energy demonstration plant in Patagonia: Description and safety issues

    Energy Technology Data Exchange (ETDEWEB)

    Aprea, Jose Luis [CNEA (Argentine Atomic Energy Commission), AAH, IRAM, Comahue University, CC 805, 8300 Neuquen (Argentina)

    2009-05-15

    Hydrogen safety issues and especially hydrogen hazard's address are key points to remove any safety-related barrier in the implementation process of hydrogen energy systems. Demonstrative systems based on hydrogen technologies represent a clear contribution to the task of showing the feasibility of the new technologies and their beneficial capabilities among the public. In this paper, the safety features of the first hydrogen energy demonstrative plant conceived in Latin America are analyzed. The facilities, located in the village of Pico Truncado, Patagonia, Argentina, serve to gain day-to-day experience in the production, storage, distribution, conversion and use of hydrogen in several applications. The plant uses electrolysis to generate pure hydrogen from renewable primary sources, taking advantage of the installed wind power capacity that is continually growing in the region. The installations were designed to accomplish with two primary objectives: total safety assurance and minimization of human errors. Some details of the plant, including a general layout, are presented here, in addition with design criteria, hydrogen hazards, structural precautions, gas monitoring system, existing regulations and safety requirements. (author)

  2. Circular structures of Bajada del Diablo (Argentina): geophysical signatures

    Science.gov (United States)

    Prezzi, C. B.; Orgeira, M. J.; Martinez, O.; Acevedo, R. D.; Ponce, F.; Goldmann, G.; Magneres, I.; Rabassa, J.

    2016-05-01

    Bajada del Diablo is located in the Northern Patagonian Massif, Chubut, Argentina. The study area includes several circular structures found in Miocene olivine basalts of the Quiñelaf Eruptive Complex and in the Late Pliocene/Early Pleistocene Pampa Sastre conglomerates. An impact origin has been proposed for these circular structures. With the aim of further investigate the proposed impact origin, topographic, gravimetric, magnetic, resistivity, palaeomagnetic and electromagnetic surveys in two circular structures (`8' and `G') located in Pampa Sastre conglomerates and in basalts of the Quiñelaf Eruptive Complex were carried out. The new geophysical results support the hypothesis of an impact origin. However, the confirmation of such an origin through the findings of shock metamorphism evidences and/or the recovery of meteorites remains elusive.

  3. Lesiones traumáticas y marcas taxonómicas en una muestra de cráneos del norte de Patagonia

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    Gordón, Florencia

    2007-01-01

    Full Text Available Actualmente se está llevando a cabo una investigación orientada a evaluar la frecuencia y el tipo de lesiones traumáticas atribuibles a situaciones de violencia interpersonal en muestras de restos óseos humanos del norte de Patagonia asignables al Holoceno tardío. Para dicho estudio, resulta indispensable un análisis de tipos e intensidad de variables postdepositacionales con el fin de estimar su impacto sobre la visibilidad de las huellas culturales. Sería esperable que en las submuestras que exhiben un grado mayor de alteración postdepositacional el registro de traumas sea menor y viceversa. El tamaño mínimo de la muestra analizada es de 400 cráneos procedentes de las cuencas inferiores de los ríos Negro y Chubut, pertenecientes a las colecciones del Museo de Ciencias Naturales de La Plata. Los resultados obtenidos hasta el presente indican que la muestra de Río Negro es la que mayor frecuencia de traumas y alteraciones tafonómicas presenta, mientras que la de Chubut exhibe baja frecuencia tanto de marcas tafonómicas como de traumas. Las variables postdepositacionales no parecen estar afectando significativamente a las observaciones de traumas culturales, por lo que las diferencias regionales en la frecuencia de este tipo de lesiones parecen reflejar diferencias reales en la exposición a factores causantes de lesiones traumáticas, entre las que se cuenta la violencia interpersonal.

  4. Revisión sistemática del género Halictillus (Hymenoptera: Halictidae: Augochlorini en la Argentina Systematic revision of the genus Halictillus (Hymenoptera: Halictidae: Augochlorini in Argentina

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    Rocío A. González-Vaquero

    2010-06-01

    Full Text Available Entre los grupos basales de la tribu Augochlorini, se encuentra el género de abejas Halictillus Moure, con sólo dos especies descriptas y ninguna revisión sistemática hasta el momento. En este trabajo, se describen cuatro especies nuevas de Halictillus de la Argentina y Chile. Las especies nuevas son: H. amplilobus sp. nov. (de Buenos Aires, Córdoba y Río Negro, H. peninsularis sp. nov. (de la Península de Valdés, Chubut, H. badiclypeus sp. nov. (de Mendoza, La Rioja y Catamarca y H. reticulatus sp. nov. (de las zonas occidentales de Chubut, Neuquén y Río Negro en la Argentina, y las regiones de La Araucanía y Los Lagos en Chile. Se presenta una clave para la determinación de las seis especies que componen el género, así como descripciones detalladas, imágenes de microscopio electrónico de barrido y un mapa de distribución geográfica de las especies nuevas.Among the basal genera of the tribe Augochlorini is the bee genus Halictillus Moure, which comprises only two described species and has no systematic revision at the moment. Four new species of Halictillus from Argentina and Chile are described in this contribution: H. amplilobus sp. nov. (from Buenos Aires, Córdoba and Río Negro Provinces, H. peninsularis sp. nov. (from Península Valdés, Chubut Province, H. badiclypeus sp. nov. (from Mendoza, La Rioja and Catamarca Provinces and H. reticulatus sp. nov. (from western Chubut, Neuquén and Río Negro Provinces in Argentina, and the regions of La Araucanía and Los Lagos in Chile. A key to the six species of the genus, as well as detailed descriptions, scanning electron microscope images and a map with distributional data of the new species are provided.

  5. Origen del tsunami de mayo de 1960 en el LagoNahuel Huapi, Patagonia: aplicación de técnicas batimétricasy sísmicas de alta resolución Origin of the tsunami of may 1960 in the LakeNahuel Huapi, Patagonia: application of the high-resolutionbathymetric and seismic techniques

    OpenAIRE

    Gustavo Villarosa; Valeria Outes; Eduardo A. Gomez; Emmanuel Chapron; Daniel Ariztegui

    2009-01-01

    El tsunami ocurrido en el lago Nahuel Haupi, PatagoniaArgentina, el 22 de Mayo de 1960, constituye el primer ejemplo de tsunami enlagos continentales en Argentina. La batimetría de detalle obtenida con sonarbatimétrico por medición de fase (SBMF) y dos perfiles sísmicos de altaresolución junto con tres testigos sedimentarios cortos del lago permitieronvincular al tsunami con el gran movimiento sísmico conocido como el terremotode Valdivia, el sismo más fuerte registrado instrumentalmente a es...

  6. Geología de la quebrada Honda, cuenca del lago La Plata, Chubut Geology of the Quebrada Honda, basin of Lago La Plata, Chubut

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    G.V. Depine

    2004-12-01

    Full Text Available La quebrada Honda, situada en el sur de la cuenca de los lagos La Plata y Fontana, en la provincia de Chubut, presenta una columna estratigráfica que comienza en el Jurásico superior con rocas calcoalcalinas de arco volcánico intermedias a ácidas de la Formación Lago La Plata. Las rocas sedimentarias que rellenan la cuenca de intraarco neocomiana corresponden al Grupo Coyhaique, dentro del cual se encuentran las Formaciones Tres Lagunas y Katterfeld, que se ubican dentro de un modelo paleoambiental como cortejo sedimentario de borde de plataforma, sucedido por un cortejo transgresivo, cuya edad es acotada al Hauteriviano inferior, debido al hallazgo de restos de Favrella americana en pelitas de la Formación Katterfeld. Vinculados con la extensión que da lugar a la cuenca se registran los cuerpos hipabisales calcoalcalinos básicos del Gabro Quebrada Honda y se los relaciona con un volcanismo de características más evolucionadas de la Formación Don Rueda, de edad neocomiana tardía. Si bien este magmatismo de arco volcánico es subaéreo, presenta indicios de interacción con cuerpos de agua por lo que corrobora la concomitancia de este evento con la sedimentación póstuma de Grupo Coyhaique. Se registra un evento de inversión tectónica que tendría una edad máxima de 80 Ma.The quebrada Honda is situated in the Lago La Plata-Fontana basin in Chubut. The stratigraphy of the area begins in the Upper Jurassic with the calc-alkaline intermediate to acidic Lago La Plata Formation rocks. The Neocomian Coyhaique Group, which includes the Tres Lagunas and Katterfeld Formations, is the sedimentary filling of the intraarc basin that was developed by that time. These units are included in a paleoenviromental model as a shelf-margin system tract followed by a transgressive system tract. The discovery of Favrella americana in the Katterfeld Formation constrains to the Early Hauterivian the age of these sequences. The hypabissal calc

  7. 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.

  8. Marine reptiles from the Late Cretaceous of northern Patagonia

    Science.gov (United States)

    Gasparini, Z.; Casadio, S.; Fernández, M.; Salgado, L.

    2001-04-01

    During the Campanian-Maastrichtian, Patagonia was flooded by the Atlantic and reduced to an archipelago. Several localities of northern Patagonia have yielded marine reptiles. Analysis of several assemblages suggests that the diversity and abundance of pelagic marine reptiles in northern Patagonia was higher by the end of the Cretaceous than previously thought. Several plesiosaurids, including Aristonectes parvidens and the polycotylid Sulcusuchus, and the first remains of mosasaurinae have been found. The Cretaceous marine reptile record from South America is scanty. Nevertheless, materials described here suggest that Tethyan and Weddelian forms converged in northern Patagonia, as seen with invertebrates.

  9. Representaciones imaginarias en la dramaturgia argentina de la postdictadura: Camino de cornisa de Alejandro Finzi

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    Mauricio Tossi

    2013-07-01

    Full Text Available Con este artículo nos proponemos indagar en determinados lineamientos poéticos desarrollados en la dramaturgia de la Patagonia Argentina durante los años de la postdictadura. Para lograr este objetivo, tomaremos como eje de estudio las representaciones imaginarias evidenciadas en los textos teatrales del período 1986-2003, y a su vez acotaremos nuestro análisis a un caso testigo: Camino de cornisa de Alejandro Finzi. With this article, we propose to investigate certain guidelines developed poetic drama of Patagonia Argentina during the years of the post-dictatorship. To achieve this goal, we will take as the axis of imaginary representations study evidenced in the texts of the period 1986-2003 and, in turn, delimit our analysis on a test case: Camino de cornisa by Alejandro Finzi.

  10. 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. PMID:27284012

  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. Hydrographic data from the GEF Patagonia cruises

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    M. Charo

    2014-02-01

    Full Text Available The hydrographic data reported here were collected within the framework of the Coastal Contamination, Prevention and Marine Management project (GEF Patagonia, which was part of the scientific agenda of the United Nations Development Program (UNDP. The project goal was to strengthen efforts to improve sustainable management of marine biodiversity and reduce pollution of the Patagonia marine environment. The observational component of the project included three multi-disciplinary oceanographic cruises designed to improve the knowledge base of the marine environment and to determine the seasonal variability of physical, biological and chemical properties of highly productive regions in the southwest South Atlantic continental shelf. The cruises were carried out on board R/V Ara Puerto Deseado, in October 2005 and March and September 2006. In each cruise, hydrographic stations were occupied along cross-shelf sections spanning the shelf from near-shore to the western boundary currents between 38° and 55° S. This paper reports the quasi-continuous vertical profiles (CTD and underway surface temperature and salinity data collected during the GEF Patagonia cruises. These data sets are available at the National Oceanographic Data Center, NOAA. US, doi:10.7289/V5RN35S0.

  13. Diversidad de musgos en ambientes degradados sujetos a restauración en el Parque Nacional Lago Puelo (Chubut, Argentina Moss diversity in degraded environments under restoring in the Lago Puelo National Park (Chubut, Argentina

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    ADRIANA E ROVERE

    2011-12-01

    Full Text Available La restauración ecológica es una disciplina que intenta recuperar atributos perdidos en un ecosistema (diversidad de especies, estructura y función. El objetivo de este trabajo fue evaluar la diversidad de musgos y sus formas de vida en tres ambientes con diferentes niveles de degradación y los sustratos en los que estos se desarrollan. El área de estudio corresponde a un sector que se está restaurando dentro de la Reserva Nacional Lago Puelo. En ella se encuentran tres ambientes distintos: (1 área remanente de bosque maduro de Nothofagus dombeyi, (2 bosque secundario de Austrocedrus chilensis, y (3 matorral dominado por especies exóticas. Se recorrió cada uno de los ambientes, registrando los sustratos con musgos, formas de vida y géneros. Los resultados evidencian una reducción de los sustratos disponibles y de las especies presentes conforme avanza el grado de alteración, desde el área de bosque maduro de N. dombeyi (9 sustratos: 17 géneros: 7 formas de vida, al sector de bosque secundario de A. chilensis (6 sustratos: 8 géneros: 5 formas de vida, siendo menor en el matorral dominado por especies exóticas (1 sustrato: 4 géneros: 3 formas de vida. Los musgos desempeñan funciones importantes en los ecosistemas, son fundamentales en el balance hídrico, pioneros en suelos inestables controlando la erosión y colonizando sitios alterados, sirven como hábitat y alimento para invertebrados, y también constituyen sitios propicios para la germinación de plantas vasculares. Si bien algunas especies leñosas ven afectada su germinación por la presencia de musgos, estos facilitan la germinación de otras especies arbóreas de los bosques templados. Los resultados podrían ser utilizados en restauración, ya sea recreando los sustratos ausentes o realizando traslado de sustratos con musgos, a fin de favorecer la recuperación de áreas boscosas degradadas considerando la biodiversidad original.Ecological restoration is a discipline that seeks to recover the attributes of an ecosystem which have been lost (species diversity, structure and function. The objective of this work was to evaluate the diversity and different life forms of mosses in three environments with varying levels of degradation, as well as the different substrates they grow on. Our study area lies within Lago Puelo National Reserve, in a sector undergoing restoration. Three different environments are found in this sector: (1 a remnant of mature Nothofagus dombeyi forest, (2 secondary Austrocedrus chilensis forest and (3 scrubland dominated by exotic species. Each of these environments was analyzed, and substrates with mosses, life forms and genera were registered. Our results showed a decrease in available substrates and species present as the level of disturbance increased, from the area of mature N. dombeyi forest (9 substrates; 17genera; 7 life forms, followed by the A. chilensis secondary forest (6 substrates: 8 genera: 5 life forms , to the scrubland dominated by exotic species (1 substrate; 4 genera; 3 life forms. Mosses carry out important functions in ecosystems, as they are essential to the water balance, they are pioneers in unstable soils, where they control erosion and colonize disturbed sites, they provide habitat and food for invertebrates, and also constitute suitable sites for the germination of vascular plants. Although the germination of some woody species is negatively affected by the presence of mosses, the germination of other temperate forest tree species is favored. These results can be useful in restoration, whether for the recreation of absent substrates or the transfer of substrates with mosses, in order to promote the recovery of degraded forest areas to their original levels of biodiversity.

  14. Geoquímica dela zona caolinizada de Mina Estrella Gaucha, provincia de Chubut Geochemistryof the kaolinized zone of Estrella Gaucha mine, Province of Chubut

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    Pedro J. Maiza

    2009-06-01

    Full Text Available Mina Estrella Gaucha es un yacimiento de caolínubicado a 70 km de la localidad de Alto Río Senguerr, provincia de Chubut,emplazado en areniscas tobáceas y conglomerádicas de la Formación Apeleg deedad cretácica inferior. La mineralogía de la zona estudiada es muy homogénea yestá constituida por dickita prácticamente pura con muy escasa cantidad dealunita y un contenido variable de cuarzo. A escala del yacimiento sedesarrolla una zonación en la que se distinguen cuatro zonas de alteración,distribuidas de techo a piso de la forma siguiente: 1 nivel superior silicificado;2 zona alunitizada; 3 zona caolinizada y 4 zona de sericita-clorita. Con elfin de determinar el origen del depósito se ha llevado a cabo un estudiomineralógico, de geoquímica de elementos mayores, menores y traza y de losisótopos estables de O y H de la zona caolinizada. Los análisis químicos deelementos mayoritarios confirman que se trata de caolín prácticamente puro. Elcontenido de elementos traza y las relaciones (P vs. S, Zr vs.Ti, Cr + Nb vs. Ti + Fe, y Ce + Y + La vs. Ba + Sr sugieren queel caolín se ha formado por alteración hidrotermal de las tobas volcánicas encajantes.La composición isotópica de los caolines muestran valores de δ18Oentre +5,1 y +8.8 ‰ y de D entre -82 y -89‰, compatibles con unorigen hidrotermal de los mismos.Estrella Gaucha mine is situated 70 km of Alto Río Senguerr(Province of Chubut.It is a kaolin deposit hosted by sandy and conglomeratic tuffs of the ApelegFormation (Lower Cretaceous. The mineralogy of the zone is very homogeneousand it is characterized by dickite almost pure, traces of alunite and quartz.There are four alteration zones. 1 silicification; 2 zone with alunite; 3 kaolinizedzone and 4 zone with sericite - chlorite. In order to know the origin of thedeposit a mineralogical, geochemical (major and trace elements and stableisotope study (O and H of the kaolinized zone was carried out. Trace elementcontent and

  15. El caso del Outburst Flood histórico de la laguna Derrumbe, Cholila, Chubut: Colapso de dique Morénico en la Cordillera Norpatagónica

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    Bruno Colavitto

    2012-09-01

    Full Text Available La laguna Derrumbe es un cuerpo de agua ubicado en los Andes Norpatagónicos en la provincia de Chubut, Argentina. Está contenida en un circo glaciario y endicada por una morena frontal del glaciar homónimo. A través del reconocimiento de campo se pudo describir a esta laguna y a un importante depósito rocoso que se halla aguas abajo de la misma, interpretado como un depósito de outburst flood. Estos depósitos son generados por procesos de alta energía relacionados con la rotura de un dique natural, en este caso un dique morénico. El estudio realizado permitió concluir que la morena frontal del glaciar Derrumbe sufrió una rotura parcial en tiempos históricos, desatando así una inundación súbita aguas abajo de la laguna, a través del valle del río Tigre, en la localidad de Cholila. En este trabajo se analizaron las posibles causas que dieron lugar a la rotura, la cual probablemente sea producto del rápido retroceso que el glaciar experimentó durante la década del ´50 y principios del ´60. Retroceso comparable con el ocurrido en muchos de los cuerpos glaciares de los Andes Patagónicos durante el último siglo.

  16. 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

    OpenAIRE

    Fernando Ballejo; Fernando Fernández; Luciano J. M. De Santis

    2012-01-01

    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 ...

  17. Estratigrafía, análisis de facies y paleoambientes de la formación cañadón asfalto en el depocentro jurásico cerro Cóndor, provincia del Chubut Stratigraphy, facies analysis and paleoenvironments of the Cañadón Asfalto Formation, Jurassic Cerro Cóndor depocenter, Chubut province

    Directory of Open Access Journals (Sweden)

    Nora Cabaleri

    2010-05-01

    Full Text Available El depocentro Cerro Cóndor representa la secuencia estratigráfica del Jurásico continental más completa de la cuenca de Cañadón Asfalto y de Sudamérica austral. Se sitúa en la Patagonia extraandina, en ambas márgenes del río Chubut medio. La sedimentación en esta cuenca pull apart, acompañada por efusiones de basalto olivínico, comenzó en el Jurásico Medio temprano. Predominan en la Formación Cañadón Asfalto los depósitos lacustres caracterizados por asociaciones de facies carbonáticas y siliciclásticas intercaladas con rocas lávicas en la base y depósitos piroclásticos hacia el techo de la unidad. Se describe el desarrollo de facies a lo largo de un corte norte-sur que abarca las secciones de estancia El Torito y de los cañadones Los Loros, Las Chacritas, Carrizal, Asfalto y Lahuincó. Las facies/microfacies carbonáticas están representadas por mudstones, wackestones,packstones, grainstones y calizas microbialíticas características de ambientes litorales, marginales y palustres. En la Formación Cañadón Asfalto se distinguen un miembro inferior (Las Chacritas, constituido por calizas, lutitas, areniscas y conglomerados, intercalados con basaltos olivínicos y por otro superior (Puesto Almada compuesto por tobas, tufitas, lutitas y areniscas. El primero es portador de una asociación palinológica de edad bajociano-bathoniana y el segundo de dinosaurios de edad tithoniana. Se describen detalladamente e ilustran las secciones estratigráficas de ambos miembros de la formación en sus localidades tipo, cañadón Las Chacritas y estancia el Torito y se reconstruyen los paleoambientes del depocentro desde el Aaleniano al Tithoniano. La edad del miembro Puesto Almada en su localidad tipo se obtuvo mediante una datación radimétrica (K/Ar de biotitas provenientes de una delgada capa de toba volcánica (147,1 ± 3,3 Ma, Tithoniano proveniente de la parte superior de la unidad.The Cerro Cóndor depocenter represents the

  18. International Uranium Resources Evaluation Project (IUREP) national favourability studies: Argentina

    International Nuclear Information System (INIS)

    Argentina is a predominantly lowland area of 2,789,240 square kilometers. The capital is Buenos Aires. The entire length of Argentina is bordered on the west by the Andes Mountains. Tile Northwest Andes-Piedmont region consists of deep valleys containing salt basins and volcanoes, and is an earthquake zone. Patagonia, in the south, is essentially an arid region of windy plateaus and valleys. The southern Andes are narrower and lower than the northern Andes and in the extreme south contain glaciers and ice fields. The east-central plain (Pampa) of Argentina has dry and humid sectors and contains most of the population. The largest rivers are chiefly in the northeast, many having only seasonal flow. There has been extensive surface and subsurface exploration for uranium in Argentina for over 20 years. Although most of the work has been performed by the CNEA, advisors from the U.S. and from the IAEA have also taken part. Private industry has been involved, but apparently only on a small scale. In the OECD report of 1970, it was stated that 400,000 square kilometers of Argentina appear very favorable for uranium while an additional 900,000 square kilometers offer fair possibilities. Uranium exploration to date suggests that sandstones of Permian and Cretaceous ages exposed in Western Argentina in the Cordillera are very promising for discovery of new deposits. Past CNEA estimates have indicated that there is considerable hope for new discoveries in those areas where reserves are now known. In addition to the known uraniferous provinces which are indeed favorable for further exploration, there are several other large areas that warrant attention. There are, for example, in the Santa Cruz area of about 15,500 square kilometers Cretaceous and Tertiary sediments with favorable facies for uranium deposition. In the Patagonia Cordillera, Jurassic, Cretaceous, and Tertiary sediments are of interest for prospecting, These rocks contain carbonaceous material and have been

  19. en Argentina

    Directory of Open Access Journals (Sweden)

    Patricia Davolos

    2005-01-01

    Full Text Available Hacia finales de la década pasada comienza a cobrar dinamismo la protesta social en Argentina como respuesta a la crisis resultante de las políticas neoliberales que dominaron la escena nacional en los noventa. En ese contexto, grupos de trabajadores ocupan empresas en riesgo de cerrar sus puertas, organizándose para operarlas en forma autogestionaria. Aquí se estudian las características del mercado de trabajo, así como las tradiciones y los recursos que permitieron a los trabajadores llevar adelante este tipo de acciones, delineando distintas trayectorias que otorgaron inteligibilidad al fenómeno analizado.

  20. 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. PMID:26637301

  1. 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.

  2. 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

  3. Morfometría dental aplicada al análisis de los procesos de diferenciación poblacional en el sudeste de la Región Pampeana y norte de Patagonia durante el Holoceno Tardío

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    Bernal, Valeria

    2005-01-01

    Full Text Available El objetivo del presente trabajo es analizar la variabilidad en la morfometría dental en muestras de restos óseos humanos del SE de la Región Pampeana asignables a distintos momentos del Holoceno tardío y comparar, desde un punto de vista espacial, el grado de similitud morfológica con muestras procedentes del NE de Patagonia (valles de Río Negro y Chubut, San Blas, Isla Gama. Se relevaron los diámetros mesiodistal y bucolingual medidos a nivel del margen cervical en la totalidad de las piezas dentales permanentes correspondientes a 130 individuos de ambos sexos. Las medidas obtenidas fueron empleadas en análisis estadísticos multivariados con el fin de evaluar el grado similitud morfológica entre las muestras. Los resultados obtenidos indican que: 1- hay diferencias entre las muestras procedentes del SE de la Región Pampeana correspondientes al Holoceno tardío inicial y final, caracterizándose estas últimas por un mayor tamaño dental; 2- la muestra del SE de la Región Pampeana correspondiente al Holoceno tardío final presenta mayor similitud morfológica con la muestra más tardía del valle de Río Negro; 3- existen variaciones cronológicas en el tamaño dental entre las muestras procedentes del NE de Patagonia.

  4. 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

  5. Evolución geomorfológica y cronología relativa de los niveles aterrazados del área adyacente a la desembocadura del río Chubut al Atlántico (Provincia del Chubut Geomorphological evolution and relative chronology of terrace levels adjacent to the Chubut River mouth to the Atlantic (Chubut Province.

    Directory of Open Access Journals (Sweden)

    Emilio F González Díaz

    2011-12-01

    Full Text Available Se describe un antiguo abanico aluvial y su posterior evolución. Las acumulaciones del antiguo abanico aluvial han sido interpretadas como la continuidad septentrional de los rodados patagónicos de la meseta Montemayor, una propuesta que es rebatida. La base metodológica del reconocimiento del antiguo abanico aluvial y su distinción genética y temporal, la constituyó el análisis geomórfico y la evaluación altimétrica. Su asignación temporal es un problema aún no resuelto. La metodología condujo a diferenciar tres sistemas geomórficos o niveles, relacionados con sucesivos episodios de agradación y erosión, los que ocupan posiciones cada vez más inferiores, coincidiendo con el complejo paleodrenaje del antiguo abanico aluvial. Sus desarrollos sucesivos son vinculados con protoríos Chubut 1, 2, 3 propuestos y el correspondiente a un paleovalle Simpson. Pese a las limitaciones apuntadas, se propone que el modelo evolutivo del antiguo abanico aluvial responde a una estructura de corte y relleno, que avalaría una composición poliformacional del antiguo abanico aluvial y además la migración progresiva del paleodrenaje hacia el sur. Un análisis geomorfológico y altimétrico diferenció un nivel superior integrado por restos de tres planicies (Pa, Pm y Pb, un nivel medio con dos terrazas (T1 y T2 y un complejo nivel inferior de cinco terrazas (T3, T4, T5 T6 y T7. Evidencias relícticas de los paleodrenajes propuestos son los paleovalles Estancia Paz y Don Morgan-Saraza del nivel superior. La edad del antiguo abanico aluvial basada en la evolución geomórfica del área de estudio, es tentativamente asignada a un incierto lapso del Pleistoceno superior entre el interglacial Sangamon y fines de la última glaciación.An ancient alluvial fan and its subsequent evolution are described. Ancient alluvial fan accumulations have been interpreted as the northern continuation of the rodados patagónicos of the Montemayor Plateau, a proposal

  6. Monitorieo de DDI en el noreste de la provincia de Chubut (2004

    Directory of Open Access Journals (Sweden)

    G. S. Zarza

    2008-06-01

    Full Text Available Un total de 668 alumnos de escolaridad primaria, de ambos sexos, fue estudiado en este monitoreo de bocio endémico en dos ciudades del noreste de la provincia de Chubut: Puerto Madryn (493 niños y Trelew (175 niños. La edad de los escolares osciló entre 5 y 15 años. La palpación tiroidea fue hecha por el conjunto de los médicos participantes. Sin embargo, con la finalidad de aunar criterios con lo realizado previamente (1-18, se tomó como única referencia la palpación de H. N., que se llevó a cabo en la totalidad de los niños estudiados. La definición del grado de bocio fue similar a la utilizada en los otros relevamientos (1. Se determinó la yoduria en muestras casuales de orina emitidas por los niños una vez que fueron palpados (161 de Puerto Madryn y 139 de Trelew. Se midió el contenido de yodo en 467 muestras de sal de consumo hogareño de Puerto Madryn y en 161 de Trelew. El examen palpatorio de los niños reveló la existencia de bocio grado 1 solamente. La prevalencia de bocio encontrada fue de 3,9 % en Puerto Madryn y de 2,9 % en Trelew. Los niveles de yoduria alcanzaron, en Puerto Madryn, una media de 188±95,8(DS μg/L y una mediana de 171 μg/L, al tiempo que en Trelew la media fue de 245±102,3 μg/L y la mediana de 196 μg/L. El contenido de yodo de las sales que aportaron los alumnos, si bien varió según la marca de sal utilizada, tuvieron un nivel relativamente adecuado de yodo en aquellas de consumo masivo. De esta manera, observamos que en la localidad de Puerto Madryn el promedio de yodo en la sal, tomada en conjunto, fue de 32,0 ± 10,9 mg/Kg, mientras que para Trelew fue de 31,5 ± 8,5 mg/Kg. Al analizar las concentraciones de yodo <15 mg/Kg, observamos que fue del 9 % en Puerto Madryn y del 5 % en Trelew. Teniendo en cuenta la línea de corte del 10 % que fija el ICCIDD (19 como valor óptimo, podemos observar que la situación de ambas poblaciones es satisfactoria. Concluimos que en estas dos ciudades del

  7. Geología de la quebrada Honda, cuenca del lago La Plata, Chubut

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    G.V. Depine

    2004-12-01

    Full Text Available La quebrada Honda, situada en el sur de la cuenca de los lagos La Plata y Fontana, en la provincia de Chubut, presenta una columna estratigráfica que comienza en el Jurásico superior con rocas calcoalcalinas de arco volcánico intermedias a ácidas de la Formación Lago La Plata. Las rocas sedimentarias que rellenan la cuenca de intraarco neocomiana corresponden al Grupo Coyhaique, dentro del cual se encuentran las Formaciones Tres Lagunas y Katterfeld, que se ubican dentro de un modelo paleoambiental como cortejo sedimentario de borde de plataforma, sucedido por un cortejo transgresivo, cuya edad es acotada al Hauteriviano inferior, debido al hallazgo de restos de Favrella americana en pelitas de la Formación Katterfeld. Vinculados con la extensión que da lugar a la cuenca se registran los cuerpos hipabisales calcoalcalinos básicos del Gabro Quebrada Honda y se los relaciona con un volcanismo de características más evolucionadas de la Formación Don Rueda, de edad neocomiana tardía. Si bien este magmatismo de arco volcánico es subaéreo, presenta indicios de interacción con cuerpos de agua por lo que corrobora la concomitancia de este evento con la sedimentación póstuma de Grupo Coyhaique. Se registra un evento de inversión tectónica que tendría una edad máxima de 80 Ma.

  8. La identidad en la encrucijada: la comunidad galesa del Chubut y las conmemoraciones del Centenario y Bicentenario de la Revolución de Mayo

    Directory of Open Access Journals (Sweden)

    Geraldine Lublin

    2013-12-01

    Full Text Available El presente artículo se propone rastrear a grandes rasgos la relación ―especial‖ entre el estado nacional argentino y, a partir de 1958, la provincia de Chubut por una parte y los colonos galeses que se establecieron en Chubut desde 1865 y sus descendientes por otra, a través del análisis de la posición de la colectividad galesa del Chubut en dos momentos históricos destacados: el Centenario y el Bicentenario de la Revolución de Mayo (1810. Al corresponderse el perfil de los galeses con la idea de poblaciones "civilizadas" que las autoridades pretendían impulsar en desmedro de los legítimos pobladores originales, estas políticas dieron lugar a una fuerte identificación histórica de la Provincia de Chubut con la llamada "gesta galesa". Se generó asimismo una peculiar dinámica triangular de las relaciones estatales, cuya evolución a través del tiempo ha desembocado en la actual promoción de la identidad chubutense como el resultado de la fusión de las culturas de los tehuelches originarios y los colonos galeses.

  9. 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 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.

  10. Liver fluke (Fasciola hepatica) naturally infecting introduced European brown hare (Lepus europaeus) in northern Patagonia: phenotype, prevalence and potential risk.

    Science.gov (United States)

    Cuervo, Pablo F; Cataldo, Sophia Di; Fantozzi, M Cecilia; Deis, Erika; Isenrath, Gabriela Diaz; Viberti, Gabriela; Artigas, Patricio; Peixoto, Raquel; Valero, M Adela; Sierra, Roberto Mera Y; Mas-Coma, Santiago

    2015-09-01

    Fascioliasis has recently been included in the WHO list of Neglected Zoonotic Diseases. Besides being a major veterinary health problem, fascioliasis has large underdeveloping effects on the human communities affected. Though scarcely considered in fascioliasis epidemiology, it is well recognized that both native and introduced wildlife species may play a significant role as reservoirs of the disease. The objectives are to study the morphological characteristics of Fasciola hepatica adults and eggs in a population of Lepus europaeus, to assess liver fluke prevalence, and to analyze the potential reservoir role of the European brown hare in northern Patagonia, Argentina, where fascioliasis is endemic. Measures of F. hepatica found in L. europaeus from northern Patagonia demonstrate that the liver fluke is able to fully develop in wild hares and to shed normal eggs through their faeces. Egg shedding to the environment is close to the lower limit obtained for pigs, a domestic animal whose epidemiological importance in endemic areas has already been highlighted. The former, combined with the high prevalence found (14.28%), suggest an even more important role in the transmission cycle than previously considered. The results obtained do not only remark the extraordinary plasticity and adaptability of this trematode species to different host species, but also highlight the role of the European brown hare, and other NIS, as reservoirs capable for parasite spillback to domestic and native cycle, representing a potentially important, but hitherto neglected, cause of disease emergence.

  11. Jurassic Paleoclimates in Argentina, a review

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    Wolfgang Volkheimer

    2008-12-01

    Full Text Available New paleoclimatic evidence from palynologic and vertebrate proxies provides more detailed data on climatic change during the Jurassic in Argentina. Comparison with paleomagnetic data shows that the Neuquén basin shifted from the highest paleolatitudes (50ºS, by the end of the Triassic until the end of the Sinemurian. During the Pliensbachian-Toarcian it moved northward, reaching the lowermost paleolatitudes (25ºS, and subsequently (Middle to Late Jurassic the area moved again and attained eventually a position similar to its present-day position (30ºS. These movements are reflected in the Jurassic palynofloras. The high frequency of the pollen genus Classopollis (Cheirolepidiacean gymnosperms is of special paleoclimatic importance in the Argentinian Jurassic, as it is indicative of seasonal aridity or semiarid conditions during large intervals of this Period. During the shift of the South American continent to the northernmost position, the arrival of an important group of Araucariaceae, represented by Callialasporites spp., in the Toarcian could indicate an amelioration related to more humid conditions. Jurassic dinocyst assemblages studied in the Neuquén basin have proved to be useful paleoclimatic and paleobiogeographic proxies. Abundant remains of marine crocodiles in the Mid- and Late Jurassic of the Neuquén basin indicate warm water temperatures for this basin, probably in excess of 20° C. The occurrence of abundant turtles and other ectothermic vertebrates in the Middle Jurassic Cañadón Asfalto Formation of Chubut is in general accordance with the warm climate indicated for this unit by geologic evidence.

  12. 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.

  13. Primer registro de Hypercompe indecisa (Lepidoptera: Noctuidae: Arctiinae en perales y álamos en la Patagonia First record of Hypercompe indecisa (Lepidoptera: Noctuidae: Arctiinae on pear trees and poplars in Patagonia

    Directory of Open Access Journals (Sweden)

    Graciela Dapoto

    2010-06-01

    Full Text Available La región del Alto Valle de Río Negro y Neuquén es la zona más importante de producción de frutas de pepita de la Argentina. La principal plaga de estos cultivos es Cydia pomonella L. (Lepidoptera:Tortricidae. Los cambios implementados en las estrategias de control, principalmente la generalización del uso de la Técnica de Confusión Sexual, han causado en los últimos años cambios en la biodiversidad en esos cultivos. Durante la temporada 2008/09, en un establecimiento frutícola de producción orgánica en Vista Alegre (Neuquén, fue detectada Hypercompe indecisa (Walker (Lepidoptera: Noctuidae, produciendo graves daños en frutos y hojas de perales y sobre el follaje de Populus spp. Se cita por primera vez H. indecisa para la Patagonia y el primer hallazgo de esta especie sobre Populus spp. y Pyrus communis L.The Alto Valle of Río Negro and Neuquén is the main production zone of pomme fruits from Argentina. The main pest is Cydia pomonella L. (Lepidoptera: Tortricidae. Changes operated in control strategies in the last years have brought changes in the biodiversity of fruit orchards. During the season 2008/09, Hypercompe indecisa (Walker (Lepidoptera: Noctuidae was detected in a fruit establishment of Vista Alegre (Neuquén under organic production causing serious damages on fruits and leaves of pear trees and in the leaves of Populus spp. Hypercompe indecisa is reported for the first time in Patagonia and is the first record of this species on Populus spp.and Pyrus communis L.

  14. Estratigrafía, análisis de facies y paleoambientes de la formación cañadón asfalto en el depocentro jurásico cerro Cóndor, provincia del Chubut

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    Nora Cabaleri

    2010-05-01

    Full Text Available El depocentro Cerro Cóndor representa la secuencia estratigráfica del Jurásico continental más completa de la cuenca de Cañadón Asfalto y de Sudamérica austral. Se sitúa en la Patagonia extraandina, en ambas márgenes del río Chubut medio. La sedimentación en esta cuenca pull apart, acompañada por efusiones de basalto olivínico, comenzó en el Jurásico Medio temprano. Predominan en la Formación Cañadón Asfalto los depósitos lacustres caracterizados por asociaciones de facies carbonáticas y siliciclásticas intercaladas con rocas lávicas en la base y depósitos piroclásticos hacia el techo de la unidad. Se describe el desarrollo de facies a lo largo de un corte norte-sur que abarca las secciones de estancia El Torito y de los cañadones Los Loros, Las Chacritas, Carrizal, Asfalto y Lahuincó. Las facies/microfacies carbonáticas están representadas por mudstones, wackestones,packstones, grainstones y calizas microbialíticas características de ambientes litorales, marginales y palustres. En la Formación Cañadón Asfalto se distinguen un miembro inferior (Las Chacritas, constituido por calizas, lutitas, areniscas y conglomerados, intercalados con basaltos olivínicos y por otro superior (Puesto Almada compuesto por tobas, tufitas, lutitas y areniscas. El primero es portador de una asociación palinológica de edad bajociano-bathoniana y el segundo de dinosaurios de edad tithoniana. Se describen detalladamente e ilustran las secciones estratigráficas de ambos miembros de la formación en sus localidades tipo, cañadón Las Chacritas y estancia el Torito y se reconstruyen los paleoambientes del depocentro desde el Aaleniano al Tithoniano. La edad del miembro Puesto Almada en su localidad tipo se obtuvo mediante una datación radimétrica (K/Ar de biotitas provenientes de una delgada capa de toba volcánica (147,1 ± 3,3 Ma, Tithoniano proveniente de la parte superior de la unidad.

  15. La extensa zona de deslizamientos de la escarpa oriental de la Pampa de Salamanca, Chubut, entre los 45°00´S y 45°45´S The extensive zone of slides on the eastern erosion scarp of Pampa de Salamanca, Chubut

    Directory of Open Access Journals (Sweden)

    E.F. González Díaz

    2004-12-01

    Full Text Available Durante la ejecución del mapa geomorfológico de la provincia del Chubut, se identificó entre las latitudes de los 45°00´S y 45°45´S y a lo largo de unos 70-75 km, una extensa faja de deslizamientos adyacente y prácticamente paralela a la escarpa oriental de la Pampa de Salamanca. Los deslizamientos, con marcado predominio de deslizamientos rotacionales, perturban el tramo superior de la secuencia sedimentaria terciaria. En los niveles arcillosos de la Formación Chenque (= Formación Patagonia, se localizarían las superficies de despegue o corte (shear para su ocurrencia. Diferencias entre sus rasgos morfológicos, tipológicos y el promotor sugerido permiten proponer cuatro zonas (I, II, III y IV de deslizamientos. La tipología aquí propuesta es provisoria, siendo sólo una base de futuras elaboraciones. Cronológicamente se diferenciaron dos conjuntos de deslizamientos: unos antiguos, más extensos y de mayor volumen, con marcadas evidencias de erosión y aquellos modernos, más reducidos, que con excelente conservación de su morfología primaria, son producto de posteriores removilizaciones acontecidas en sectores de los antiguos, que se expresan esencialmente bajo la forma de flujos (corrientes de tierra o earthflows y más ocasionalmente como deslizamientos rotacionales secundarios (slumps. Entre los de mayor edad, los de la zona I, son definidos como afines en general a un deslizamiento rotacional con una fase distal de flujo; ocasionalmente habrían superado los límites del actual acantilado marino. A pesar de esta primera apreciación, no se descarta su consideración como ejemplos de expansiones laterales (lateral spreads. Los de la zona II, son definidos como deslizamientos rotacionales múltiples retrogradantes. Aquellos de la zona III integran un conjunto de deslizamientos con un marcado control estructural (N50°E, en sus desprendimientos. La zona IV, compone una estrecha y continua faja adyacente a la Pampa de

  16. Crecimiento y desarrollo de una población infanto juvenil de la provincia de Chubut

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    Torres, María Fernanda

    1999-01-01

    Full Text Available La diferenciación y adaptación ontogenética son temas centrales en antropología biológica por cuanto su modificación puede afectar la dinámica evolutiva poblacional. Numerosos factores estresantes actúan provocando variación en la expresión fenotípica y nuevas respuestas adaptativas. En el presente trabajo se determinó el crecimiento de niños de 5 a 14 años contrastando con estándares internacionales. La muestra se constituyó con 473 escolares de Río Mayo (Chubut, de ambos sexos. Se relevaron y calcularon variables corporales. Para la comparación con los estándares los datos fueron convertidos a escores z y contrastados además mediante pruebas de Wilcoxon. La estadística empleada consistió en análisis multifactorial de la varianza y pruebas de LSD. Si bien hubo crecimiento en todos los grupos etáreos analizados, los valores obtenidos difirieron significativamente de los correspondientes al estándar. En varones, a excepción del pliegue subescapular, que presentó escores z superiores al estándar las restantes variables se ubicaron entre 0 y -2 DS, siendo más afectadas las estaturas total y sentado y el área muscular. En mujeres, se observó una situación similar a excepción del área adiposa y la masa corporal, con valores mayores al estándar. Estos resultados evidencian la presencia de una desnutrición que abarca toda la franja etárea. La disminución de la talla y el aumento del tejido adiposo constituyen sin duda, respuestas adaptativas que permiten la supervivencia de los individuos frente a la injuria nutricional.

  17. Petrología de la secuencia volcánica cenozoica en el área del arroyo Ranquil Huao: Meseta de Somún Curá. Patagonia Extraandina

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    M. B. Remesal

    2002-09-01

    Full Text Available En el norte de la Patagonia extraandina, involucrando parte de las provincias geográficas de Río Negro y Chubut se extiende un amplio derrame basáltico tipo plateau. El valle del arroyo Ranquil Huao, en el sector austral del plateau, en las proximidades de la localidad de Telsen, expone una secuencia interesante y bastante completa de esa asociación volcánica cenozoica. En este corte es posible estudiar no sólo los flujos basálticos correspondientes a la Formación Somún Curá, sino también los derrames denominados Basalto La Mesada, incluidos en la Superunidad Quiñelaf y los depósitos tobáceos del Grupo Sarmiento. Los basaltos de la Formación Somún Curá presentan rasgos petrográficos y geoquímicos similares a los del Basalto La Mesada (Superunidad Quiñelaf. El flujo piroclástico que se intercala en la parte más alta de la Formación Somún Curá complementa la estratigrafía conocida para esta unidad. Las características de las basanitas aflorantes en el tramo medio del valle del arroyo Ranquil Huao permiten diferenciarlas de las rocas que constituyen las otras unidades basálticas en la secuencia.

  18. Límites naturales del norte de la Patagonia Natural boundaries of Northern Patagonia

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    V.A. Ramos

    2004-12-01

    Full Text Available En esta nota se presenta el consenso alcanzado por la Comisión de la Carta del Servicio Geológico Minero Argentino para definir los límites geológicos de la Patagonia. Este se estableció a lo largo de la dorsal de Huincul, rasgo estructural de primer orden que separa dos sectores de diferente comportamiento cortical. Este límite ha sido trazado sobre la base de numerosas observaciones geológicas y geofísicas, que marcan una importante división en el Engolfamiento Neuquino, y que hacia el oeste se puede seguir a través de la Cordillera de Los Andes. Hacia el este se extiende por el valle del río Negro hasta costa afuera de la plataforma continental.This note presents the consensus obtained by the Comisión de la Carta del Servicio Geológico Minero Argentino to define the geological boundaries of Patagonia. This was established along the Huincul High, a first order structural feature that separates two sectors of different crustal behaviour. This boundary was established based on numerous geological and geophysical observations, that points out to an important division of the Neuquén Embayment, and that to the west it can be traced across the Andean Cordillera. This boundary extends to the east along the Río Negro valley until off-shore of the continental platform.

  19. Indigenous identity and textiles: an economic policy strategies in the province of Chubut La identidad indígena y sus textiles: estrategias de una política económica en la provincia de Chubut

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    Patricia María Méndez

    2010-01-01

    Full Text Available From the conception of the identity of individuals and of the groups as an elaboration, arises that the current indigenous identity employed by the state in the province of Chubut is functional to a policy which aims to prevent the emigration of the few people in rural areas of the province. It affirms that such a strategy is not new and that in the past other versions of this identity have also been useful to legitimate power projects. Through ethnographic and historical work, we explore some physical and social characteristics of rural areas of that province, some provincial regulations of government agencies, and certain attributes, preterits and present, of the indigenous identity employed by the state and of one of its symbols, Mapuche tissues. Laterally it refers in what way this identity is considered by some identified.A partir de la concepción de la identidad de las personas y de los grupos como una elaboración, se plantea que la actual identidad indígena empleada por el Estado en la provincia de Chubut resulta funcional a una política que pretende evitar la emigración de los escasos pobladores de las zonas rurales de la provincia. Se afirma que tal estrategia no es novedosa y que en el pasado otras versiones de esa identidad también han resultado útiles a los proyectos del poder legítimo. Mediante un trabajo etnográfico e histórico, se analizan algunas características físicas y sociales de la zona rural de esa provincia, algunas normativas de organismos gubernamentales provinciales, y ciertos atributos pretéritos y actuales de la identidad indígena empleada por el Estado y de uno de sus símbolos, los tejidos mapuches. Lateralmente se refiere de qué manera esa identidad es considerada por algunos identificados.

  20. 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.

  1. Airborne laser altimetry survey of Glaciar Tyndall, Patagonia

    DEFF Research Database (Denmark)

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

    2007-01-01

    of - 3.2 m a(-1) [Raymond, C., Neumann, T.A., Rignot, E., Echelmeyer, K.A., Rivera, A., Casassa, G., 2005. Retreat of Tyndall Glacier, Patagonia, over the last half century. Journal of Glaciology 173 (51), 239-247.]. A good agreement was also found between ice elevation changes measured with laser data...... and previous results obtained with Shuttle Radar Topography Mission (SRTM) data. We conclude that airborne laser altimetry is an effective means for accurately detecting glacier elevation changes in Patagonia, where an ice thinning acceleration trend has been observed during recent years, presumably...

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

    OpenAIRE

    Esperanza C Iranzo; Juan Traba; Pablo Acebes; Benito A González; Cristina Mata; 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 19(th) 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 displac...

  3. 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

    Directory of Open Access Journals (Sweden)

    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.

  4. Drainage network over the migrating front of dynamic uplift in Patagonia

    Science.gov (United States)

    Jeandet, Louise; Robert, Xavier; Audin, Laurence; Husson, Laurent; Guillaume, Benjamin

    2016-04-01

    Dynamic topography disturbs the regional morphology at long wavelength and with very low topographic gradients. Nevertheless, fluvial erosion and the drainage pattern should respond to the spatial and temporal topographic variations. In Patagonia, the mid-Miocene, opening and northward migration of an asthenospheric window beneath the South American plate triggered a northward propagating wave of dynamic topography. Based on a morphometric analysis, we explore the long-wavelength response of the drainage system to the recent dynamics of the continental lithosphere. Our analysis of Patagonian rivers (stream profile analysis) and basins (R/Sr analysis) shows a transient state of the drainage network responding to a likely recent signal that prevails at the latitudes of the Chile Triple Junction in Argentina. Moreover, the distribution of the perturbation signal among the drainage network shows a South-to-North gradient, with the low Strahler order tributaries more affected with increasing latitudes. We interpret this observation as the differential timing of response to a Northward propagating signal of dynamic topography. We further use the geometry of the drainage network combined to numerical model predictions to infer the characteristic response time of the surface processes. While the main tributaries respond within ~1-3 Ma, the lower order remain disturbed for longer times. This observation is further supported by the persistently high mean elevation where incision is high, which we take as indicative of the fact that erosion has not yet thoroughly achieved its resurfacing action.

  5. 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.

  6. 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)

  7. 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).

  8. Interactions among four parasite species in an amphipod population from Patagonia.

    Science.gov (United States)

    Rauque, C A; Semenas, L

    2013-03-01

    Parasites commonly share their hosts with specimens of the same or different parasite species, resulting in multiple parasites obtaining resources from the same host. This could potentially lead to conflicts between co-infecting parasites, especially at high infection intensities. In Pool Los Juncos (Patagonia, Argentina), the amphipod Hyalella patagonica is an intermediate host to three parasites that mature in birds (the acanthocephalan Pseudocorynosoma sp. and larval stages of two Cyclophyllidea cestodes), in addition to a microsporidian (Thelohania sp.), whose life cycle is unknown, but very likely to be monoxenous. The aim of this study was to describe interactions between these parasite species in their amphipod host population. Amphipods were collected monthly between June 2002 and January 2004 to assess parasite infection. Infection prevalence and mean intensity were greatest in larger male amphipods for all parasite species. We also found a positive association between Thelohania sp. and both Pseudocorynosoma sp. and Cyclophyllidea sp. 1 infections, though Pseudocorynosoma sp. and Cyclophyllidea sp. 1 were negatively associated with each other. We conclude that contrasting associations between parasite species may be associated with competition for both food intake and space in the haemocoel.

  9. Muscular reconstruction and functional morphology of the forelimb of early Miocene sloths (Xenarthra, Folivora) of Patagonia.

    Science.gov (United States)

    Toledo, Néstor; Bargo, M Susana; Vizcaíno, Sergio F

    2013-02-01

    Early Miocene sloths are represented by a diversity of forms ranging from 38 to 95 kg, being registered mainly from Santacrucian Age deposits in southern-most shores of Patagonia, Argentina. Their postcranial skeleton differs markedly in shape from those of their closest living relatives (arboreal forms of less than 10 kg), Bradypus and Choloepus. In order to gain insight on functional properties of the Santacrucian sloths forelimb, musculature was reconstructed and a comparative, qualitative morphofunctional analysis was performed, allowing proposing hypotheses about biological role of the limb in substrate preferences, and locomotor strategies. The anatomy of the forelimb of Santacrucian sloths resembles more closely extant anteaters such as Tamandua and Myrmecophaga, due to the robustness of the elements, development of features related to attachment of ligaments and muscles, and conservative, pentadactylous, and strong-clawed manus. The reconstructed forelimb musculature was very well developed and resembles that of extant Pilosa (especially anteaters), although retaining the basic muscular configuration of generalized mammals. This musculature allowed application of powerful forces, especially in adduction of the forelimb, flexion and extension of the antebrachium, and manual prehension. These functional properties are congruent with both climbing and digging activities, and provide support for proposed Santacrucian sloths as good climbing mammals, possibly arboreal or semiarboreal, being also capable diggers. Their climbing strategies were limited, thus these forms relied mainly on great muscular strength and curved claws of the manus to move cautiously on branches.

  10. Distribution and hybridization between Culex pipiens and Culex quinquefasciatus (Diptera: Culicidae in Argentina

    Directory of Open Access Journals (Sweden)

    Walter R. Almirón

    1995-08-01

    Full Text Available To better undesrtand the distribution of Culex pipiens and Cx. quinquefasciatus in Argentina, samples were collected from six localities situated in a North-South line from Castelli (Chaco Province to Puerto Madryn (Chubut Province. Identification was based on the morphology of male genitalia. Only Cx. quinquefasciatus was found in Castelli and Esperanza, while in Rosario, 95.3% belonged to this species and 4.7% represented hybrid forms. Southern samples included only Cx. pipiens. With the purpose of verfying if Cx. pipiens and Cx. quinquefasciatus hybridize, different crosses between the two species were perfomed. All crosses produced viable egg rafts. Hatching ranged from 70 to 100%, except in one cross, female Cx. pipiens x male Cx. quinquefasciatus, where a high incompatibility was observed (11.1%hatch. The F1 hybrids obtained all crosses were fertile. The finding of hybrid forms in nature can be interpreted as evidence for subspecific status of Cx. pipiens and Cx. quinquefasciatus in Argentina.

  11. Variación regional del crecimiento y estado nutricional: Chubut

    Directory of Open Access Journals (Sweden)

    Dahinten, Silvia Lucrecia

    2005-01-01

    Full Text Available La descripción y el análisis del crecimiento humano han ocupado gran parte de las investigaciones de antropobiólogos, médicos y biólogos humanos, entre otros. En Argentina si bien se dispone de información de prevalencias de malnutrición, existe dificultad en la comparación debido a que en la mayor parte de los casos hay disparidad en las técnicas y/o metodologías empleadas. El objetivo del presente trabajo es analizar el estado nutricional de la población de Puerto Madryn a fin de disponer de elementos diagnósticos que permitan su contrastación con otras provincias argentinas. Peso corporal (kg. y talla (cm. fueron medidos en una muestra de 3042 niños y adolescentes (1575 varones y 1467 mujeres durante 2003- 2004. Con los datos obtenidos se analizaron los indicadores Peso/Edad (P/E, Peso/Talla (P/T, Talla/Edad (T/E e Indice de Masa Corporal (IMC. La prevalencia de cada indicador se calculó siguiendo los puntos de corte recomendados por la OMS: para bajo P/E, T/E y P/T se utilizó el percentilo 5, para sobrepeso (S el intervalo percentilar 85-95 (>P85 IMC P95. Los resultados obtenidos indicaron las siguientes prevalencias totales: Desnutrición: 5.6%, Bajo P/E: 4.7%, Baja T/E: 10.2.% Bajo P/T: 1.8%, S: 16.2% y O: 9.1%. Los resultados obtenidos indican niveles moderados de desnutrición, siendo altos los porcentajes de sobrepeso y obesidad.

  12. 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

  13. Argentina Welcomes Chinese Enterprises

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ On July 13,China-Argentina Entrepreneur Luncheon Meeting was held in Beijing.Cristina Fernandez de Kirchner,President of Argentina,Hui Liangyu,Vice Prime Minister of China and Wan Jifei,President of CCPIT attended the meeting.

  14. Isotopic studies on detrital zircons of Silurian-Devonian siliciclastic sequences from Argentinean North Patagonia and Sierra de la Ventana regions: comparative provenance

    Science.gov (United States)

    Uriz, Norberto J.; Cingolani, Carlos A.; Chemale, Farid; Macambira, Moacir B.; Armstrong, Richard

    2011-04-01

    The Silurian-Devonian siliciclastic sedimentary units known as Sierra Grande Formation and the upper part of the Ventana Group crop out in the eastern area of the North Patagonian Massif and in the Ventania system, toward the Atlantic border of Argentina. Both sequences show similar stratigraphical characteristics and were deposited in a shallow marine platform paleoenvironment. Previous contributions have provided evidence of an allochthonous Patagonia terrane that amalgamate to Gondwana during the Permian-Triassic. However, other lines of research support a crustal continuity southward, where the Pampean and Famatinian events extend into the northern Patagonia. In either case, the detrital input to the Eo-Mesopaleozoic basins generated along the passive margin tectonic setting should reflect the sedimentary sources. In this contribution, new age data on the sedimentary provenance of these units is provided by U-Pb and Lu-Hf isotopic studies on detrital zircons, using LA-ICP-MS and SHRIMP methodologies. The main sedimentary sources of detrital zircons for both regions are of Cambrian-Ordovician and Neoproterozoic age, while a secondary mode is Mesoproterozoic. Zircons from older cratonic sources (Mesoarchean-Paleoproterozoic ages) are scarcely recorded. The sample from the upper section of the Devonian Lolén Formation (Ventana Group) shows an important change in the sedimentary provenance, with a main mode of Mesoproterozoic detrital zircons. Detrital source areas considering the orogenic cycles known for southwest South America (Famatinian, Pampean-Brasiliano, Mesoproterozoic-`Grenvillian' and Paleoproterozoic-`Transamazonian') are proposed.

  15. 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

  16. Quantifying mass balance processes on the Southern Patagonia Icefield

    DEFF Research Database (Denmark)

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

    2014-01-01

    We present surface mass balance simulations of the Southern Patagonia Icefield driven by downscaled reanalysis data. The simulations were validated and interpreted using geodetic mass balances, measured point balances and a complete velocity field of 5 the Icefield from spring 2004. The high...... measured accumulation of snow as well as the high measured ablation is reproduced by the model. The overall modeled surface mass balance was positive and increasing during 1975–2011. Subtracting the surface mass balance from geodetic balances, calving fluxes were inferred. Mass losses of the SPI due to...... spatially distributed accumulation measurements can help to reduce the uncertainties of the different terms in the mass balance of the Southern Patagonia Icefield....

  17. Paleoparasitological analysis of a raptor pellet from southern Patagonia.

    Science.gov (United States)

    Fugassa, M H; Sardella, N H; Denegri, G M

    2007-04-01

    Organic remains attributable to one regurgitated pellet were examined. The pellet, belonging to a bird of prey and collected from a cave of Southern Patagonia, was dated at 6,540 +/- 110 yr. With standard paleoparasitological procedures, eggs of Capillaria sp. and a mite, Demodex sp., were found. The parasites found in the pellet belong to a rodent ingested by the bird. The present report constitutes the first paleoparasitological study of a regurgitated pellet. PMID:17539429

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

    OpenAIRE

    Kozameh, Livia Febes; Benítez, Ana María

    2005-01-01

    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 dentici...

  19. Estudio de quitridiomicosis por Batrachochytrium dendrobatidis en anfibios anuros del Litoral, Cuyo y Patagonia Argentina

    OpenAIRE

    Ghirardi, Romina

    2012-01-01

    La quitridiomicosis es una enfermedad emergente que en los últimos años ha sido vinculada a la muerte masiva de los anfibios. Esta enfermedad es causada por el hongo acuático zoospórico Batrachochytrium dendrobatidis -Bd- (Orden Rhyzophydiales). La infección de los anfibios comienza cuando las zoosporas móviles contactan un animal susceptible y penetran en su piel. Las alteraciones producidas por esta infección interfieren con varias funciones epiteliales de los anfibios como la circulación y...

  20. Identification of Calderas Associated With The Acidic Jurassic Volcanism of Southern Patagonia, Argentina

    Science.gov (United States)

    Chernicoff, C. J.; Salani, F. M.

    During the Jurassic, the Patagonian region was subject to a predominantly acidic volcanism locally known as the Chon Aike Volcanic Province, related to the breakup of Gondwana. It comprises ignimbrites, breccias and agglomerates, and a minor component of rhyolitic and dacitic lava domes. In the study area (Río Seco region, Santa Cruz Province), the Jurassic volcanics are largely overlain by Neogene and Quaternary sediments. However, the aeromagnetic survey of this region has unravelled the magnetic pattern of the volcanics, notably two conspicuous calderas, since the young cover sediments are non-magnetic. The magnetic susceptibility of the volcanic rocks ranges 50 to 80 x 10-5 S.I., as oppossed to the nearly null values of the overlying sediments. The geological interpretation of the aeromagnetic survey is mostly based on the analytic signal of the total magnetic intensity, where two distinct sub-circular magnetic lineaments have been recognized and regarded as calderic structures. The eastern caldera, 30 km wide, is centered at 48º 52' S.L./ 68º 02' W.L., and the western caldera, 23 km wide, is centered at 48º 53' S.L. / 68º 29' W.L.. In addition, a number of smaller, high gradient magnetic anomalies have been identified and interpreted as intra- and extracaldera domes. In the eastern caldera, a number of domes follow an anular pattern of fractures regarded as the boundary of an older, outer caldera. A magnetic circular lineament located within the latter structure has been interpreted as a younger, inner caldera which presents a number of small domes in its central depression; additional domes are also located in between the two calderic structures. The western caldera is less complex since it comprises a single structure with intra-caldera domes. The total magnetic gradient (analytic signal) associated with the domes is one order of magnitude higher (0.1 to 0.2) than the mean value of the region (0.03). In addition to the anular fractures and domes, a small number of radial fractures/faults have also been identified. The depth of the magnetic sources (top of the domes), as estimated from the Euler deconvolution of the magnetic data, is 350 to 550 m, depending on the structural index utilized, therefore indicating the local thickness of the non-magnetic cover.

  1. 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 and fluvioglacial deposits). Al

  2. Assessing the performance of macroinvertebrate metrics in the Challhuaco-Ñireco System (Northern Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Melina Mauad

    2015-09-01

    Full Text Available ABSTRACT Seven sites were examined in the Challhuaco-Ñireco system, located in the reserve of the Nahuel Huapi National Park, however part of the catchment is urbanized, being San Carlos de Bariloche (150,000 inhabitants placed in the lower part of the basin. Physico-chemical variables were measured and benthic macroinvertebrates were collected during three consecutive years at seven sites from the headwater to the river outlet. Sites near the source of the river were characterised by Plecoptera, Ephemeroptera, Trichoptera and Diptera, whereas sites close to the river mouth were dominated by Diptera, Oligochaeta and Mollusca. Regarding functional feeding groups, collector-gatherers were dominant at all sites and this pattern was consistent among years. Ordination Analysis (RDA revealed that species assemblages distribution responded to the climatic and topographic gradient (temperature and elevation, but also were associated with variables related to human impact (conductivity, nitrate and phosphate contents. Species assemblages at headwaters were mostly represented by sensitive insects, whereas tolerant taxa such as Tubificidae, Lumbriculidae, Chironomidae and crustacean Aegla sp. were dominant at urbanised sites. Regarding macroinvertebrate metrics employed, total richness, EPT taxa, Shannon diversity index and Biotic Monitoring Patagonian Stream index resulted fairly consistent and evidenced different levels of disturbances at the stream, meaning that this measures are suitable for evaluation of the status of Patagonian mountain streams.

  3. Munida casadioi (Schweitzer & Feldmann, 2000) from the Eocene of the Bariloche area, Patagonia (Argentina)

    NARCIS (Netherlands)

    Garassino, Alessandro; Angeli, De Antonio

    2003-01-01

    New material forces a reconsideration of Austromunida casadioi Schweitzer & Feldmann, 2000. Originally the type species of a new genus, we find that this is only a species of the genus Munida Leach, 1820.

  4. 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...

  5. 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-

  6. Eupsophus calcaratus (Anura, Leptodactilydae: ampliación de su distribución geográfica y hábitats en Argentina

    Directory of Open Access Journals (Sweden)

    Úbeda, Carmen A.

    2000-03-01

    Full Text Available Argentina, Provincia de Chubut, Departamento de Futaleufú: 1 Parque Nacional Los Alerces, margen NE del Lago Menéndez, proximidad desembocadura Arroyo Zanjón Hondo, (42°42' S, 71°41' O, 520 m snm, 14/febrero/1997. Un ejemplar macho adulto, colector: Carmen A. MACN 37034. 2 Parque Nacional Los Alerces, Arroyo Torrecillas, Lago Menéndez, 18/enero/1972. Colector: Monaglio. MACN 29946. 3 Parque Nacional Los Alerces, Lago Futalaufquen, 25/abril/1969. Colector: Foerster. CENAI 7163. 4 Parque Nacional Los Alerces, margen norte del Lago 1 [actualmente parte del Lago Amutui Quimei], (43°01' S, 71°46' O, 1-2/1971. Colectores: Monadio, Garrido y Bianchini. MACN 29723/28.

  7. El volcanismo del complejo Marifil en Arroyo Verde, vertiente suroriental del Macizo de Somún Cura, Chubut

    Directory of Open Access Journals (Sweden)

    Marcelo J Márquez

    2010-05-01

    Full Text Available Se describen en este trabajo las facies volcánicas pertenecientes al Complejo Marifil que afloran en la localidad de Arroyo Verde, vertiente suroriental del macizo de Somún Cura, provincia del Chubut. Se discriminan facies de ignimbritas riolíticas, brechas piroclásticas, domos y domos vítreos traquíticos y diques riolíticos. Las relaciones de campo indican que las ignimbritas fueron el primer evento eruptivo que se alternaron con esporádicas coladas de bloques y cenizas. Luego se produjo la intrusión de las facies dómicas y por último la de los diques riolíticos. Las facies descriptas tienen composiciones que varían entre riolitas y traquitas con altos contenidos de K, característicos de las rocas pertenecientes a este complejo. Teniendo en cuenta las características observadas se propone un mecanismo fisural de erupción en esta localidad.

  8. Equinococosis canina en un sector del Departamento de Río Cuarto,Provincia de Córdoba, Argentina Canine echinococcosis in an area of Río Cuarto Department(Córdoba, Argentina)

    OpenAIRE

    J. GONZALEZ PERALTA; Gonzalez, G.; A. SBAFFO; A. BESSONE; M. CHASSAGNADE; L UGNIA; A. Weyers; N. ESPOSITO; G. BERNARDES; A. Alcoba; C. GUENDULAIN; Flores, P

    1998-01-01

    La hidatidosis es una zoonosis parasitaria de distribución universal,producida por un céstode del género Equinococus granulosus,que tiene como huésped definitivo de mayor importancia epidemiológicaal canino. El hombre y los animales de producción son huéspedesintermediarios. En Argentina las zonas que muestran altas tasas de transmisiónde hidatidosis al hombre son: La Patagonia, la Pampa Húmeda y elLitoral. En el resto del país los casos de hidatidosis humana senotifican sólo esporádicamente,...

  9. Revisión taxonómica y estratigráfica de esporas cicatricosas del Cretácico Inferior de Patagonia: 1. Géneros Appendicisporites Weyland & Krieger, Nodosisporites Deák y Plicatella Maljavkina Taxonomic and stratigraphic revision of Lower Cretaceous cicatricose spores from Patagonia: 1. Genera Appendicisporites Weyland & Krieger, Nodosisporites Deák and Plicatella Maljavkina

    Directory of Open Access Journals (Sweden)

    Sergio Archangelsky

    2010-06-01

    Full Text Available Sedimentitas del Cretácico Inferior halladas en distintas localidades de la Cuenca Austral, Patagonia, incluyen numerosos tipos de esporas cicatricosas de helechos que pertenecen a la familia Anemiaceae. En esta contribución inicial se presenta el estudio taxonómico de 13 especies que se refieren a los géneros Appendicisporites Weyland & Krieger, Nodosisporites Deák y Plicatella Maljavkina. Se discuten los criterios más actualizados sobre la caracterización de estos géneros, los que permiten sugerir varios cambios sistemáticos de taxones descriptos previamente en Argentina. El material procede de perfiles de superficie y de sondeos de la Plataforma Continental, y corresponde a varias unidades litoestratigráficas cuyas edades oscilan entre el Valanginiano y Albiano. Por primera vez se citan para Argentina las especies Nodosisporites cf. N. genuinus (Bolkhovitina Davies, Appendicisporites cf. N. unicus (Markova Singh, Plicatipollenites jansonii (Pocock Davies, P. cf. P. degenerata (Thiergart Davies y P. pseudotripartita (Bolkhovitina como una nueva combinación. Además se aceptan las combinaciones realizadas por otros autores de las siguientes especies argentinas: P. archangelskyi Davies (por Cicatricosisporites giganteus Archangelsky & Gamerro y Plicatipollenites baqueroensis (Archangelsky & Gamerro Davies. Finalmente, se efectúan comentarios sobre la distribución estratigráfica de las especies estudiadas en perfiles y secciones de subsuelo.Lower Cretaceous sediments found in different localities of the Austral Basin in Patagonia, contain several cicatricose fern spore types belonging to the family Anemiaceae. This initial contribution is a taxonomic study of 13 species referred to the genera Appendicisporites Weyland & Krieger, Nodosisporites Deák and Plicatella Maljavkina. The most recent criteria to characterise these genera are discussed and systematic changes of taxa previously described in Argentina are suggested. The

  10. Prácticas poscoloniales y resistencias locales: el caso de la mina de oro de Esquel (Argentina)

    OpenAIRE

    Yannopoulos, Alexis

    2012-01-01

    Este artículo constituye un esbozo de investigación sobre el conflicto social que se produjo entre 2002 y 2003 en la localidad de Esquel (Patagonia argentina): se propone una síntesis no exhaustiva de los trabajos realizados sobre el tema y se dibujan algunas líneas de reflexión respecto a eventuales futuras investigaciones. Establecida la cronología de los acontecimientos del conflicto, se abordan los riesgos medioambientales y sociales acarreados por la minería de oro a cielo abierto con ut...

  11. La extensa zona de deslizamientos de la escarpa oriental de la Pampa de Salamanca, Chubut, entre los 45°00´S y 45°45´S

    Directory of Open Access Journals (Sweden)

    E.F. González Díaz

    2004-12-01

    Full Text Available Durante la ejecución del mapa geomorfológico de la provincia del Chubut, se identificó entre las latitudes de los 45°00´S y 45°45´S y a lo largo de unos 70-75 km, una extensa faja de deslizamientos adyacente y prácticamente paralela a la escarpa oriental de la Pampa de Salamanca. Los deslizamientos, con marcado predominio de deslizamientos rotacionales, perturban el tramo superior de la secuencia sedimentaria terciaria. En los niveles arcillosos de la Formación Chenque (= Formación Patagonia, se localizarían las superficies de despegue o corte (shear para su ocurrencia. Diferencias entre sus rasgos morfológicos, tipológicos y el promotor sugerido permiten proponer cuatro zonas (I, II, III y IV de deslizamientos. La tipología aquí propuesta es provisoria, siendo sólo una base de futuras elaboraciones. Cronológicamente se diferenciaron dos conjuntos de deslizamientos: unos antiguos, más extensos y de mayor volumen, con marcadas evidencias de erosión y aquellos modernos, más reducidos, que con excelente conservación de su morfología primaria, son producto de posteriores removilizaciones acontecidas en sectores de los antiguos, que se expresan esencialmente bajo la forma de flujos (corrientes de tierra o earthflows y más ocasionalmente como deslizamientos rotacionales secundarios (slumps. Entre los de mayor edad, los de la zona I, son definidos como afines en general a un deslizamiento rotacional con una fase distal de flujo; ocasionalmente habrían superado los límites del actual acantilado marino. A pesar de esta primera apreciación, no se descarta su consideración como ejemplos de expansiones laterales (lateral spreads. Los de la zona II, son definidos como deslizamientos rotacionales múltiples retrogradantes. Aquellos de la zona III integran un conjunto de deslizamientos con un marcado control estructural (N50°E, en sus desprendimientos. La zona IV, compone una estrecha y continua faja adyacente a la Pampa de

  12. Variación morfométrica postcraneal en muestras tardías de restos humanos de Patagonia: una aproximación biogeográfica Postcranial morphometric variation in late Holocene human remains from Patagonia: a biogeographic approach

    Directory of Open Access Journals (Sweden)

    Marien Béguelin

    2006-12-01

    Full Text Available Durante los últimos cinco años se está llevando a cabo una serie de estudios orientados a discutir diferentes hipótesis acerca de la dinámica de las poblaciones cazadoras-recolectoras tardías de las regiones pampeana y patagónica en base a evidencia morfológica y desde la perspectiva de la denominada geografía evolutiva. Continuando con esta línea de investigación, en este trabajo se consideran algunos aspectos de la variación fenotípica postcraneal en muestras de Patagonia continental y Tierra del Fuego en relación con expectativas derivadas de la biogeografía. Se analizaron muestras de esqueletos masculinos y femeninos procedentes de diferentes sitios y localidades del área de estudio, agrupadas en cuatro conjuntos correspondientes a franjas latitudinales de 5° de ancho cada una. Se consideraron variables vinculadas con el tamaño corporal (longitud máxima del fémur y con las proporciones corporales (índices braquial y crural. Los resultados obtenidos indican la existencia de un patrón de variación geográfica que puede ser explicado por la convergencia de diferentes procesos y factores, tales como la adaptación climática local y movimientos migratorios de pequeño y mediano rango (centro y sur de Patagonia continental y Tierra del Fuego, migraciones de mediano y largo rango (norte de Patagonia e insularidad (Tierra del Fuego.During the last five years a number of studies have been carried out that examined different hypotheses regarding the evolutionary dynamics of late Holocene human populations in the Pampas and Patagonia in central and southern Argentina. This research is primarily based on morphological evidence and has its theoretical roots in evolutionary geography. Following this line of inquiry, the aim of the present paper is to perform an exploratory analysis -taking into account some general biogeographic premises- of some aspects of postcranial phenotypic variation using skeletal samples from Patagonia and

  13. Astronomy in Argentina

    CERN Document Server

    Muriel, Hernán

    2013-01-01

    This article analyses the current state of Astronomy in Argentina and describes its origins. We briefly describe the institutions where astronomical research takes place, the observational facilities available, the training of staff and professionals, and the role of the institutions in scientific promotion. We also discuss the outreach of Astronomy towards the general public, as well as amateur activities. The article ends with an analysis of the future prospects of astronomy in Argentina.

  14. El volcanismo del complejo Marifil en Arroyo Verde, vertiente suroriental del Macizo de Somún Cura, Chubut The volcanism of the Marifil Complex in Arroyo Verde, Southeastern slope of the Somun Cura Massif, Chubut

    Directory of Open Access Journals (Sweden)

    Marcelo J Márquez

    2010-05-01

    Full Text Available Se describen en este trabajo las facies volcánicas pertenecientes al Complejo Marifil que afloran en la localidad de Arroyo Verde, vertiente suroriental del macizo de Somún Cura, provincia del Chubut. Se discriminan facies de ignimbritas riolíticas, brechas piroclásticas, domos y domos vítreos traquíticos y diques riolíticos. Las relaciones de campo indican que las ignimbritas fueron el primer evento eruptivo que se alternaron con esporádicas coladas de bloques y cenizas. Luego se produjo la intrusión de las facies dómicas y por último la de los diques riolíticos. Las facies descriptas tienen composiciones que varían entre riolitas y traquitas con altos contenidos de K, característicos de las rocas pertenecientes a este complejo. Teniendo en cuenta las características observadas se propone un mecanismo fisural de erupción en esta localidad.Marifil Complex volcanic facies that crop out in the locality of Arroyo Verde, SE slope of Macizo de Somún Cura, are described here. Rhyolitic ignimbrite facies, pyroclastic breccias, traquitic domes and vitreous domes, and rhyolitic dikes are distinguished. Field relationships point out the ignimbrites as the first effusive event. Some sporadically block and ash flows are intercalated within the ignimbrites. These deposits were intruded by domes; the latest event is represented by the intrusion of the rhyolitic dykes. Chemical composition of these rocks varies between high K rhyolites and traquites, which correspond to typical characteristics of the Marifil Complex rocks. The observations allow proposing a fissural mechanism of eruption for these facies in this locality.

  15. El cambio climático global en la Patagonia desde el viaje de Charles Darwin hasta nuestros días The global climatic change in Patagonia and Tierra del Fuego since voyage of Charles Darwin until present times

    Directory of Open Access Journals (Sweden)

    Jorge Rabassa

    2010-08-01

    todos, los glaciares de circo de la Patagonia y Tierra del Fuego desaparecerán durante las próximas dos décadas, y tanto los glaciares de valle como los mantos de hielo de la Patagonia se verán severamente reducidos en su superficie y espesor. Como consecuencia de la desaparición paulatina de los glaciares, se esperan significativos cambios en las condiciones ambientales, hidrológicas, geomorfológicas, turísticas y del patrimonio natural de estas regiones, que afectarán severamente a aquellas comunidades que viven en ellas.The Voyage of the Beagle that brought Charles Darwin to South America in AD 1832- 1835 and particularly, to the present territory of Argentina, was developed under very unfavorable climatic conditions, much colder, drier and windier than today. These circunstances correspond to the dominant conditions during the last phase of the little ice age, which was a global, cold event that characterized the 17th to the 19th centuries. This phase is known as the Dalton Minimum, in reference to the relative small amount of solar spots, which generated a diminution of the solar radiation and in consequence, the lowering of the global mean temperatures in that period. Darwin was perfectly conscious of those climatic conditions, which were clearly shown in Europe at those times and particularly in the Alps, and therefore he is clearly showing that in his writings. Since Darwin's Voyage to Patagonia, the climatic and environmental conditions have changed substantially, particularly after AD 1850 and finally, after the middle portion of the AD 1970's decade. Some of the most important consequences of global climate change are rising mean annual or seasonal temperature, rising or diminishing precipitations at the regional level, rising global sea level, and an increase in the frequency of extreme meteorological events. The impact of these changes has been observed in the glaciers of Patagonia and Tierra del Fuego, at least since AD 1978 and, particularly, in

  16. Los dueños del rebaño. Origen étnico y capacidad ovina en Chubut

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    Fernando Coronato

    2015-04-01

    Full Text Available Continuando la línea de investigación inaugurada por Elsa Barbería en “Los dueños de la tierra” en Santa Cruz, avanzamos sobre la distribución de las diferentes comunidades étnicas y su parte en el poblamiento patagónico a partir del análisis cartográfico diacrónico. Para el último período del proceso utilizamos la base de datos del catastro del Chubut (2006 para evaluar « la capacidad ganadera» (entendida como la acumulación de hectáreas y ovinos de cada comunidad étnica. Estas fueron asociadas a los grupos patronímicos identificados previamente, a saber: alemán, bóer, británico (inglés y escocés, español, francés, galés, italiano, mapuche, polaco, tehuelche y vasco. Las Sociedades Anónimas se consideraron como un grupo aparte. Del tratamiento estadístico de los datos se obtuvo la superficie media de las (más de 2000 propiedades, la talla media del rebaño y la cosecha de lana de cada grupo, detectándose diferencias significativas entre algunos de ellos. Las Sociedades Anónimas se despegan solitarias hacia los latifundios, mientras que en el extremo opuesto se ubican los grupos aborígenes, arrinconados en los minifundios y la subsistencia. Estos datos relativamente actuales muestran la continuidad de los procesos identificados en el análisis catastral de etapas previas del poblamiento que se remontan a más de un siglo.

  17. Diversity of cingulate xenarthrans in the middle-late Eocene of Northwestern Argentina

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    Martín R. Ciancio

    2016-08-01

    Full Text Available The study of Paleogene mammals of intermediate and low latitudes has increased in the last decades and has been clearly demonstrated their importance in the comprehension of the evolution and faunistic changes outside Patagonia. The study of these faunas permits establishing new comparisons among contemporaneous faunistic associations, completing the distributional patterns, and evaluating evolutionary changes in the lineages in relation to climatic conditions prevailing in each of the different regions. In this work we study the diversity of Dasypodidae recovered from the Geste Formation (Northwestern Argentina. Bearing levels of Geste Formation were referred alternatively to a Barrancan subage of Casamayoran SALMA (middle Eocene, Lutetian–Bartonian or a Mustersan SALMA (middle–late Eocene, Bartonian–Priabonian on faunistic comparations with their equivalent in Patagonia, although absolute isotopic data indicates ca. 37–35 Ma (late Eocene, Priabonian. We described the following taxa of Dasypodidae: (i Dasypodinae Astegotheriini: cf. Astegotherium sp., ?Prostegotherium sp., Parastegosimpsonia cf. P. peruana; (ii Dasypodinae indet.; (iii Euphractinae Euphractini: Parutaetus punaensis sp. nov.; (iv Dasypodidae incertae sedis: Pucatherium parvum, Punatherium catamarcensis gen. et sp. nov. In comparison with other beds bearing Eocene cingulate faunas from Northwestern Argentina, Geste Formation presents the greatest diversity of dasypodids. This association is consistent with a late Eocene age and shows a taxonomic and biogeographic relevant features given by a unique specific composition: (i it differs from that known for contemporaneous faunas from Southern latitudes and younger associations from more tropical areas; (ii it includes genera with close affinities to those distant areas; (iii it presents unique taxa typical from Eocene units exposed at Northwestern Argentina. This highlights the evolutionary and biogeographic meaning of the

  18. Current situation of the facilities, equipments and human resources in nuclear medicine in Argentina

    International Nuclear Information System (INIS)

    The current situation of nuclear medicine in Argentina, taking into account the facilities, their equipment and human resources available is presented in this paper. A review and analysis of the equipment, including technical characteristics and a survey of the professionals and technicians of the area, was carried out. In Argentina, there are 266 centers of nuclear medicine distributed all over the country. The operating licenses are granted by the Nuclear Regulatory Authority (Autoridad Regulatoria Nuclear - ARN). Forty four percent of the installed equipment are SPECT of 1 or 2 heads and 39,4 % are gamma camera. Besides, there are eleven PET operating in Argentina. There are 416 nuclear medicine physicians with individual permit for diagnostic purposes and 50% of them has also individual permit for treatment purposes. With the purpose of analyzing the regional distribution of the available resources in nuclear medicine, the country was divided into 7 geographical regions: City of Buenos Aires, Province of Buenos Aires, Pampa, Cuyo, Northeast, Northwest and Patagonia. From the analysis of the gathered information it is possible to conclude that the nuclear medicine equipment as well as the personnel present an irregular distribution, with a major concentration in the City of Buenos Aires and Province of Buenos Aires. The Northeast region presents the lowest number of Nuclear Medicine centers and the Patagonia region has the lowest number of medicine nuclear physicians with individual permits. The number of SPECT and gamma cameras is 7,3 per million of inhabitants. The information about the available resources in nuclear medicine presented in this paper and its comparison with the international information available provide elements for a better planning of the future activities in the area not only for the operators but also from the regulatory point of view. (author)

  19. Primer registro de Hypercompe indecisa (Lepidoptera: Noctuidae: Arctiinae en perales y álamos en la Patagonia

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    Graciela DAPOTO

    2010-01-01

    Full Text Available La región del Alto Valle de Río Negro y Neuquén es la zona más importante de producción de frutas de pepita de la Argentina. La principal plaga de estos cultivos es Cydia pomonella L. (Lepidoptera: Tortricidae. Los cambios implementados en las estrategias de control, principalmente la generalización del uso de la Técnica de Confusión Sexual, han causado en los últimos años cambios en la biodiversidad en esos cultivos. Durante la temporada 2008/09, en un establecimiento frutícola de producción orgánica en Vista Alegre (Neuquén, fue detectada Hypercompe indecisa (Walker (Lepidoptera: Noctuidae, produciendo graves daños en frutos y hojas de perales y sobre el follaje de Populus spp. Se cita por primera vez a H. indecisa para la Patagonia y el primer hallazgo de esta especie sobre Populus spp. y Pyrus communis L.

  20. Optical Flow Applied to Time-Lapse Image Series to Estimate Glacier Motion in the Southern Patagonia Ice Field

    Science.gov (United States)

    Lannutti, E.; Lenzano, M. G.; Toth, C.; Lenzano, L.; Rivera, A.

    2016-06-01

    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.

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

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    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.

  2. Contaminants in the southern tip of South America: Analysis of organochlorine compounds in feathers of avian scavengers from Argentinean Patagonia.

    Science.gov (United States)

    Martínez-López, E; Espín, S; Barbar, F; Lambertucci, S A; Gómez-Ramírez, P; García-Fernández, A J

    2015-05-01

    The aim of this study was to assess the exposure to organochlorine compounds (OC) in 91 primary wing feathers of avian scavengers, Turkey vulture (Cathartes aura), American black vulture (Coragyps atratus) and Southern crested caracaras (Polyborus plancus) from the southern tip of South America, in the Argentinean Patagonia. We analyzed for a series of OC including hexachlorocyclohexane (HCH) isomers, endosulfan, aldrin, dieldrin, endrin, dichlorodiphenyltrichloroethane (p,p'-DDT), dichlorodiphenyldichloroethane (p,p'-DDD), dichlorodiphenyldichloroethylene (p,p'-DDE), heptachlor and heptachlor-epoxide. This is the first study on OC in feathers of three terrestrial top carnivores from South America. OC concentrations found in the studied species were much higher than those found in feathers of raptors from Europe and Asia, which likely indicate their high use in the region, specifically in agriculture, and other possible uses of OC in this area. ∑HCH had the highest median concentration, followed by ∑Drins, ∑DDT, ∑Heptachlor, and ∑Endosulfan, similar to those reported in several food samples in Argentina. On the other hand, differences in OC profiles between species and areas may be related to feeding and migratory habits, as well as the molt period. Three individuals showed ∑DDT (DDT, DDD and DDE) concentrations in feathers related to sublethal effects. However, this comparison should be used with caution due to problems with extrapolating such data across tissues and species.

  3. A new species of Haplosporidium Caullery & Mesnil, 1899 in the marine false limpet Siphonaria lessonii (Gastropoda: Siphonariidae) from Patagonia.

    Science.gov (United States)

    Ituarte, Cristián; Bagnato, Estefanía; Siddall, Mark; Cremonte, Florencia

    2014-05-01

    A new species of Haplosporidium Caullery & Mesnil, 1899 parasitising the pulmonate gastropod Siphonaria lessonii Blainville in Patagonia, Argentina, is described based on morphological (scanning and transmission electron microscopy) and sequence (small subunit ribosomal RNA gene) data. Different stages of sporulation were observed as infections disseminated in the digestive gland. Haplosporidium patagon n. sp. is characterised by oval or slightly subquadrate spores with an operculum that is ornamented with numerous short digitiform projections of regular height, perpendicular to and covering its outer surface. The operculum diameter is slightly larger than the apical diameter of the spore. Neither the immature nor mature spores showed any kind of projections of the exosporoplasm or of the spore wall. Regarding phylogenetic affinities, the new species was recovered as sister to an undescribed species of Haplosporidium Caullery & Mesnil, 1899 from the polychaete family Syllidae Grube from Japanese waters. The morphological characters (ornamentation of the operculum, spore wall structure, shape and size of spores, and the lack of spore wall projections) corroborate it as an as yet undescribed species of Haplosporidium and the first for the phylum in marine gastropods of South America. Siphonaria lessonii is the only known host to date.

  4. Persistence of a Mesozoic, non-therian mammalian lineage (Gondwanatheria) in the mid-Paleogene of Patagonia

    Science.gov (United States)

    Goin, Francisco J.; Tejedor, Marcelo F.; Chornogubsky, Laura; López, Guillermo M.; Gelfo, Javier N.; Bond, Mariano; Woodburne, Michael O.; Gurovich, Yamila; Reguero, Marcelo

    2012-06-01

    We describe two isolated molariforms recovered from early-middle Eocene (early Lutetian) levels of northwestern Patagonia, Argentina. Comparisons with major lineages of therian and non-therian mammals lead us to refer them to a new genus and species of Gondwanatheria (Allotheria). There is a single root supporting each tooth that is very short, wide, rounded, and covered by cementum; the steep sidewalls, lack of a neck between the crown and root, and the heavily worn stage in both molariforms suggest that they were of a protohypsodont type. Both teeth are strongly worn at their centers, all along their length, with the labial edge less worn than the lingual; they show strong transverse crests that alternate with lingual grooves. The protohypsodont aspect of the teeth, as well as the strong, transverse crests, are suggestive of sudamericid affinities; on the other hand, the thin enamel layer and the occlusal pattern formed by the crests and grooves shows more similarities to molariform teeth of the Ferugliotheriidae. The new taxon adds evidence regarding the (1) extensive radiation of the Gondwanatheria throughout the Southern Hemisphere, (2) persistence of several lineages well after the Cretaceous/Paleogene boundary, and (3) early evolution of hypsodont types among South American herbivorous mammals.

  5. Craniofacial variation, body size and ecological factors in aboriginal populations from central Patagonia (2000-200 years B.P.).

    Science.gov (United States)

    Bernal, Valeria; Béguelin, Marien; Gordón, Florencia; Cobos, Virginia A; Gonzalez, Paula N; Lotto, Federico P

    2014-04-01

    Previous studies have shown that ecological factors had a significant role in shaping the patterns of craniofacial variation among South American populations. Here, we evaluate whether temperature and diet contributed to facial diversification in small geographic areas. Facial size and shape of 9 osteological samples from central Patagonia (Argentina) were described using 2D landmarks and semilandmarks. Data on mean annual temperature, diet composition (δ(13)C and δ(15)N values) and femoral head maximum breadth, used as a proxy of body mass, were obtained for each sample. We then tested the association of body mass and the ecological variables with facial morphology using spatial regression techniques and a model selection approach. Akaike Information Criterion produced disparate results for both components of facial morphology. The best model for facial size included temperature and body mass proxy, and accounted for more than 80% of variation in size. Lower temperatures were related to larger facial sizes. Body mass was negatively associated with facial size and showed no relationship with the temperature. This suggests a relatively independent variation of cranial traits and body mass at the spatial scale studied here. Facial shape was not associated with the temperature or diet composition, contrasting with the patterns observed at larger spatial scales. Our results point out that the effect of climatic variables on cranial traits might be a source of morphological differentiation not only at large scales but also in small geographic areas, and that size and shape display a differential preservation of environmental signals. PMID:24462195

  6. Quantifying mass balance processes on the Southern Patagonia Icefield

    OpenAIRE

    Schaefer, M.; Machguth, H.; M. Falvey; Casassa, G.; Rignot, E

    2015-01-01

    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 measured accumulation of snow of up to 15.4 m w.e. yr−1 (meters water equivalent per year) as well as the high measured ablation of up to 11 m w.e. yr−1 is reproduced by the model. Th...

  7. Revisión taxonómica y estratigráfica de esporas cicatricosas del Cretácico Inferior de Patagonia: 2. Géneros Cicatricosisporites Potonié & Gelletich y Ruffordiaspora Dettmann & Clifford Taxonomic and stratigraphic revision of Lower Cretaceous cicatricose spores from Patagonia: 2. Genera Cicatricosisporites Potonié & Gelletich and Ruffordiaspora Dettmann & Clifford

    Directory of Open Access Journals (Sweden)

    Sergio Archangelsky

    2010-12-01

    Full Text Available Se estudian 9 especies del género Cicatricosisporites y 5 especies del género Ruffordiaspora, halladas en diferentes perfiles que abarcan sedimentitas referidas al Cretácico Inferior del subsuelo y superficie en la Cuenca Austral, Patagonia, Argentina. Dos especies son nuevas, Cicatricosisporites pramparoana y Ruffordiaspora cardielensis mientras que 5 especies se describen por primera vez en Argentina, Cicatricosisporites cf. C. hallei, C. minutaestriatus, C. venustus, R. cf. R. crassiterminatus y Ruffordiaspora ludbrookiae. Se resumen en un cuadro las principales características de cada taxón con el fin de facilitar las comparaciones y determinaciones, dada la aparente similitud que existe entre algunos. Se concluye que en el Cretácico Inferior las esporas de la familia Anemiaceae fueron componentes comunes en las asociaciones palinológicas de la Cuenca Austral. Se reconocen tres grupos de especies de ambos géneros aquí estudiados: 1 especies que están presentes en todo el Cretácico Inferior (Cicatricosisporites annulatus, C. cuneiformis, C. hughesii, C. sp. 2, Ruffordiaspora australiensis, R. ludbrookiae y R. ticoensis, 2 especies que se presentan en el Aptiano y Albiano (Cicatricosisporites cf. C. hallei, C. pramparoana y Ruffordiaspora cardielensis, y 3 especies exclusivamente albianas (Cicatricosisporites venustus, C. minutaestriatus y Ruffordiaspora cf. R. crassiterminatus.Nine species of the genus Cicatricosisporites and five species of the genus Ruffordiaspora were found in several surface and subsurface sections of Lower Cretaceous sediments from the Austral Basin, Patagonia, Argentina. Two new species: Cicatricosisporites pramparoana and Ruffordiaspora cardielensis, are described, while 5 species: Cicatricosisporites cf. C. hallei, C. minutaestriatus, C. venustus, Ruffordiaspora cf. R. crassiterminatus nov. comb. and R. ludbrookiae are mentioned for the first time in Argentina. In view of the similarities that may be found

  8. 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.

  9. Yacimientos de Halloysita en Mamil Choique,provincia de Río Negro, Patagonia Halloysite deposits in Mamil Choique, provinceof Río Negro, Patagonia

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    Fernanda Cravero

    2009-11-01

    Full Text Available En la provincia de Río Negro, al norte de la localidadde Mamil Choique, se explotan depósitos minerales cuyo material secomercializacomo caolín. Mediante estudios mineralógicos se determinó que el mineralprincipal es halloysita-(10 Å acompañado por cantidades menores de esmectita ycristobalita, siendo el primer yacimiento en la Argentina de este mineral y unode los pocos en el mundo. La halloysita se presenta en cristales tubulares,cilíndricos, menores a 0,5 µm de largo y condiámetros menores a 0,2 µm. Laidentificación de la halloysita-(10Å, corroborada mediante la intercalacióncon formamida, fue además posible debido al cuidado puesto en el embalaje ytraslado de las muestras pues este mineral se deshidrataa temperatura ambientetransformándose en halloysita- (7 Å, la cual es fácilmente confundida concaolinita. El mineral se presenta en zonas alteradas, sobre rocas ignimbritas decomposición riolítica pertenecientes a la Formación Huitrera de edad eocena.Este proceso se caracteriza principalmente por una intensa lixiviación de loselementos alcalinos y alcalinos térreos, y un incremento en la concentraciónrelativa de alúmina. El origen de la alteración no se ha establecido conprecisión, pero la mineralogía simple, la ausencia de minerales característicosy de elementos minoritarios o trazas de ambientes epitermales, sumado a laexistencia de un clima templado húmedo a partir del Eoceno, permite suponer unaformación de tipo meteórico. La determinación de halloysita plantea la revisiónen la utilización de material de este depósito, ya que este mineral poseepropiedades muy diferentes a las de los otros minerales del grupo del caolín.A white material in RíoNegro Province, Patagonia, has been mined as kaolin. Through mineralogicalstudies, the main mineral has been identified as halloysite-(10 Å with minoramounts of smectite and cristobalite. Halloysite tubes and cylinders are about0.5 µm long and 0.2 µm in diameter

  10. 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 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.

  11. Chilenia y Patagonia: ¿un mismo continente a la deriva? Chilenia and Patagonia, the same continent adrift?

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    Renata Nela Tomezzoli

    2012-06-01

    Full Text Available La zona de estudio está ubicada a lo largo del margen sudoccidental del Gondwana y abarca desde las Sierras Australes hasta el Bloque de San Rafael y el Macizo Nordpatagónico. A partir de la integración de los datos obtenidos en trabajos de campo, estudios paleomagnéticos, de anisotropía de susceptibilidad magnética, e información obtenida por otros autores, se concluye en este trabajo que la deformación en esta región del Gondwana podría haber comenzado durante el Devónico Medio y se relacionaría con la colisión de Patagonia desde el sur y de Chilenia desde el oeste. Siendo que Chilenia y Patagonia habrían comenzado a colisionar con Gondwana al mismo tiempo, se plantea la posibilidad de que hayan sido parte de un mismo terreno alóctono a la deriva. Posteriormente, en el Carbonífero, colisionó desde el sur el Macizo del Deseado. La deformación post-colisional asociada a estos procesos habría continuado hasta el Pérmico, produciendo movimientos latitudinales, como parte del ajuste y acople final de los bloques continentales que configuraron la Pangea Triásica en conjunto con el núcleo cratónico principal del Gondwana.The study area is located along the southwestern margin of Gondwana, ranging from Sierra de la Ventana (Sierras Australes to the San Rafael Block and the North Patagonian Massif. From the integration of data from feld work, paleomagnetic studies, anisotropy of magnetic susceptibility, and information obtained by other authors in this paper is concluded that the deformation in this part of Gondwana may have begun during the Middle Devonian and would relate to the collision of Patagonia from the south and Chilenia from the west. Since Chilenia and Patagonia have begun to collide with Gondwana at the same time raises the possibility that they were part of the same allochthonous drif terrain. Later in the Carboniferous, from the south collided the Deseado Massif. The post-collisional deformation associated with

  12. El origen y evolución temprana de las serpientes : Análisis anatómico y filogenético de los ofidios cretácicos y paleógenos de la Patagonia y Bolivia

    OpenAIRE

    Scanferla, Carlos Agustín

    2010-01-01

    Este trabajo de tesis doctoral tiene como objetivo principal el análisis de dos relevantes escamados procedentes del Cretácico Superior de la Patagonia Argentina, Najash rionegrina y Dinilysia patagonica, como así también dos nuevas serpientes avanzadas del grupo de los Macrostomata, (denominados Taxón A y B) procedentes de la localidad del Terciario Inferior (Paleoceno) de Tiupampa, Bolivia. Se realizó un análisis anatómico detallado de estos taxones fósiles en conjunto con un gran número de...

  13. Evolución geomorfológica y cronología relativa de los niveles aterrazados del área adyacente a la desembocadura del río Chubut al Atlántico (Provincia del Chubut

    Directory of Open Access Journals (Sweden)

    Emilio F González Díaz

    2011-12-01

    Full Text Available Se describe un antiguo abanico aluvial y su posterior evolución. Las acumulaciones del antiguo abanico aluvial han sido interpretadas como la continuidad septentrional de los rodados patagónicos de la meseta Montemayor, una propuesta que es rebatida. La base metodológica del reconocimiento del antiguo abanico aluvial y su distinción genética y temporal, la constituyó el análisis geomórfico y la evaluación altimétrica. Su asignación temporal es un problema aún no resuelto. La metodología condujo a diferenciar tres sistemas geomórficos o niveles, relacionados con sucesivos episodios de agradación y erosión, los que ocupan posiciones cada vez más inferiores, coincidiendo con el complejo paleodrenaje del antiguo abanico aluvial. Sus desarrollos sucesivos son vinculados con protoríos Chubut 1, 2, 3 propuestos y el correspondiente a un paleovalle Simpson. Pese a las limitaciones apuntadas, se propone que el modelo evolutivo del antiguo abanico aluvial responde a una estructura de corte y relleno, que avalaría una composición poliformacional del antiguo abanico aluvial y además la migración progresiva del paleodrenaje hacia el sur. Un análisis geomorfológico y altimétrico diferenció un nivel superior integrado por restos de tres planicies (Pa, Pm y Pb, un nivel medio con dos terrazas (T1 y T2 y un complejo nivel inferior de cinco terrazas (T3, T4, T5 T6 y T7. Evidencias relícticas de los paleodrenajes propuestos son los paleovalles Estancia Paz y Don Morgan-Saraza del nivel superior. La edad del antiguo abanico aluvial basada en la evolución geomórfica del área de estudio, es tentativamente asignada a un incierto lapso del Pleistoceno superior entre el interglacial Sangamon y fines de la última glaciación.

  14. 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

  15. Niche segregation between wild and domestic herbivores in Chilean Patagonia.

    Directory of Open Access Journals (Sweden)

    Esperanza C Iranzo

    Full Text Available 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 19(th 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.

  16. 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.

  17. Paleosuelos en Cordones litorales de la formación Caleta Valdés, pleistoceno superior, noreste de Chubut

    Directory of Open Access Journals (Sweden)

    Pablo J Bouza

    2014-03-01

    Full Text Available El objetivo de este trabajo es evaluar los cambios climáticos y ecológicos registrados en los paleosuelos de la Formación Caleta Valdés (Pleistoceno superior y determinar las propiedades pedogenéticas que pueden ser utilizadas como indicadores paleopedológicos. El área de estudio se encuentra en el NE de la provincia del Chubut, en el ámbito de la Península Valdés. La estratigrafía superficial presenta tres unidades de sedimentación que fueron alternativamente edafizadas. El paleosuelo más antiguo (3Btkb-3Bkmb, formado en los depósitos gravosos de los cordones pleistocenos, presenta un mayor contenido de Fe pedogenético -presumiblemente hematita - un predominio de esmectitas y menores contenidos de δ13C y de δ18O, lo que indica una mayor proporción de plantas C3 y un clima estacionalmente contrastante de tipo mediterráneo (régimen xérico. Considerando que los cordones se habrían depositado en el MIS 5e, la formación del paleosuelo habría ocurrido durante el final de ese piso isotópico interglacial. Este paleosuelo habría sido erosionado y sepultado por episodios sedimentológicos, posiblemente asociados a los procesos periglaciares de los pisos isotópicos 4-2. Estos depósitos constituyeron -conjuntamente con adiciones eólicas- los materiales parentales de un nuevo suelo que evolucionó a la secuencia de horizontes 2Btb-2Btkb-2Bkb-2Ck durante un lapso de estabilidad ambiental. Este evento pedogenético probablemente esté asociado al lapso más húmedo y con marcada estacionalidad de las precipitaciones, ocurrido durante el Tardiglacial - Holoceno temprano, que fue seguido de un período de mayor sequía y aumento de temperaturas durante el Holoceno medio registrado en la región. El tercer evento pedogenético está representado por las secuencias de horizontes A-C.

  18. Efectos de la instalación de un gasoducto sobre algunas propiedades del suelo superficial y la cobertura vegetal en el NE de Chubut Gas-pipeline installation effects on superficial soil properties and vegetation cover in Northeastern Chubut

    Directory of Open Access Journals (Sweden)

    Esteban Kowaljow

    2008-07-01

    Full Text Available En este trabajo describimos el impacto del tendido de un gasoducto y de la reposición parcial del material removido, sobre algunas propiedades físicas y químicas del suelo y sobre la cobertura vegetal en tres sitios ecológicos del nordeste de Chubut. En cada sitio se identificaron 4 zonas diferentes: zona 1, faja desmontada y compactada por el tránsito de maquinaria pesada; zona 2, faja desmontada, con posterior reposición del suelo y la vegetación removidos; y otras dos zonas correspondientes a la estepa adyacente no disturbada: montículos asociados a arbustos y espacios entre montículos. Los mayores valores de densidad aparente se encontraron en los suelos de la zona 1 y en los del entremontículo (1,43 Mg m-3. La resistencia a la penetración fue significativamente mayor en las zonas 1 y 2, ambas zonas presentaron valores de resistencia a la penetración superiores a 1 MPa. La tasa de infiltración fue mucho mayor en el montículo (261 mm h-1 que en el resto de las zonas. La velocidad de infiltración de la zona 2 (85 mm h-1 fue mayor a la de la zona 1 (35 mm h-1 y el entremontículo (50 mm h-1. Los contenidos de carbono orgánico y nitrógeno de los suelos de las zonas 1 y 2 fueron similares a los del entremontículo y significativamente inferiores a los del montículo, excepto en la zona 2 de uno de los sitios ecológicos. La remoción de la vegetación y el suelo superficial, y el posterior tránsito de maquinaria pesada durante la instalación del gasoducto produjeron un fuerte impacto sobre las propiedades físicas del suelo. La mayor limitación de los suelos disturbados fue su baja capacidad para incorporar agua, derivada principalmente de su elevada compactación y baja porosidad, lo que explicaría en parte la lenta recuperación de la cobertura vegetal en la zona 1. En ninguno de los tres sitios estudiados, la reposición del material removido por la actividad del desmonte significó una medida de recuperación eficaz

  19. Jurassic tetrapods and flora of Cañadón Asfalto Formation in Cerro Cóndor area, Chubut Province Flora y tetrápodos del Jurásico de la Formación Cañadón Asfalto en el área de Cerro Cóndor, provincia de Chubut

    OpenAIRE

    Ignacio H. Escapa; Juliana Sterli; Diego Pol; Laura Nicoli

    2008-01-01

    The plant and tetrapod fossil record of the Cañadón Asfalto Formation (Middle to Late Jurassic) found in Cerro Cóndor area (Chubut Province) is summarized here. The flora is dominated by conifers (Araucariaceae, Cupressaceae sensu lato) but also includes ferns and equisetaleans. The tetrapod fauna is composed of dinosaur taxa described in the 70's as well as other remains recently described and other vertebrate groups such as amphibians, turtles, and mammals. The amphibian remains have been i...

  20. Procedencia de areniscas del Grupo Chubut en el área central de la Sierra de San Bernardo. Análisis preliminar Provenance of the Chubut Group Sandstones in the central area of the Sierra de San Bernardo. Preliminary analysis

    Directory of Open Access Journals (Sweden)

    M.A. Tunik

    2004-12-01

    Full Text Available Se llevaron a cabo análisis petrográficos de detalle que permitieron determinar las modas detríticas en areniscas del Grupo Chubut con el fin de inferir el marco tectónico del área de aporte de las mismas. Sobre la base de las muestras estudiadas, se observan características petrográficas distintivas entre areniscas de las Formaciones Matasiete, Castillo y Bajo Barreal. La presencia de trizas dentro de las areniscas de las Formaciones Castillo y Bajo Barreal sugeriría una depositación concomitante con volcanismo de arco activo. El ploteo de las modas detríticas en diagramas de discriminación de ambiente de procedencia mostró una diferenciación entre las unidades del Grupo Chubut. La Formación Matasiete presenta una procedencia de arco magmático no disectado, mientras que las muestras correspondientes a las Formaciones Castillo y Bajo Barreal sugieren una procedencia de arco magmático transicional o disectado. Esto último sumado a la presencia de trizas de caída directa podría explicarse por la migración del arco volcánico hacia el oeste y a la exposición de las raíces del arco volcánico del Cretácico inferior por deformación en la faja plegada concomitante con un volcanismo activo ubicado hacia el oeste de la zona de estudio.Petrographic studies were performed in order to characterize the detrital modes of the Chubut Group sandstones. Matasiete, Castillo and Bajo Barreal Formation showed distinctive petrographic characteristics. The presence of shards on the Castillo and Bajo Barreal Formations suggests that the deposition took place on an active volcanic setting. The detrital modes indicates derivation from three different environments among the Chubut Group. The Matasiete Formation shows a provenance from a non-dissected magmatic arc. Meanwhile, the detrital modes of the Castillo and Bajo Barreal Formations suggest derivation from a transitional to dissected arc. A westward migration of the volcanic arc and the

  1. La depresión del "bajo" del diablo" (NE del Chubut: Una propuesta geomórfica acerca de su origen y su evolución

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    Emilio F González Díaz

    2013-06-01

    Full Text Available El Bajo del Diablo está situado en el NE de Chubut. Se analizan sus geoformas internas y marginales, proponiéndose su génesis por deflación y se presenta un esquema de su evolución, que está íntimamente influenciada por los cambios climáticos cuaternarios. Se carece de datos para establecer con precisión la temporalidad de los hechos. Un protorío Chubut generó un abanico aluvial local ó nivel superior durante el Interglacial Sangamon (± 120.000 años. Su degradación y el desarrollo del nivel medio (T1 y T2 por un prerío Chubut, causó la exposición de un sector del débil sustrato terciario, un núcleo marginado por las resistentes psefitas de los niveles. El establecimiento local de las frías, secas y ventosas condiciones de la Última Glaciación, condujo a una progresiva exhondación por deflación (asociada a meteorización del núcleo, proceso que culminó en una depresión poco profunda y de pendientes suaves (Pfannen. Un húmedo intervalo pluvial, facilitó la formación de un efímero lago en ella. Su progresiva reducción -expresada por cordones litorales en posiciones cada vez más bajas- estuvo motivada por un retorno a las frías y secas condiciones previas. La coetánea reactivación de la deflación, llevó a la consiguiente mayor profundización de la depresión. Durante este proceso, se produjo la exhumación del paleorelieve del basamento regional, compuesto por las volcanitas jurásicas de la Formación Marifil. Finalizado el período glaciario, el proceso fluvial y el de remoción en masa ampliaron más aun la depresión, que hoy aparece caracterizada por abruptas pendientes y mayor profundidad (Wannen. Dos perfiles expresan la relaciones entre las distintas geoformas reconocidas.

  2. Conflictividad socioambiental en América Latina. El escenario post crisis de 2001 en Argentina

    Directory of Open Access Journals (Sweden)

    Lorena Bottaro

    2012-01-01

    Full Text Available En este artículo presentamos una aproximación a los casos que inauguraron un nuevo ciclo de conflictos relacionados con la defensa de los "recursos naturales" y los territorios en Argentina. Para ello realizaremos, en la primera parte del texto, una breve descripción de los primeros momentos de los conflictos socioambientales que tuvieron lugar, por un lado, alrededor de la instalación de plantas de procesamiento de celulosa al margen del Río Uruguay -en la localidad de Gualeguaychú, litoral argentino-, y por otro, en torno a la llegada de un proyecto para la explotación minera a cielo abierto en la localidad de Esquel, patagonia argentina. En un segundo momento, presentaremos una caracterización de los movimientos sociales de la década de 1990 en Argentina con el objeto de identificar similitudes y divergencias entre estos actores y los movimientos socioambientales propios de principio de siglo.

  3. 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…

  4. A lab in Argentina

    Science.gov (United States)

    2016-06-01

    Mauricio Erben, a researcher at the National University of La Plata and the National Scientific and Technical Research Council, talks to Nature Chemistry about his experience of research in Argentina, and how it is inherently linked to the country's political climate.

  5. Albert Einstein visits Argentina

    CERN Document Server

    Gangui, A; Gangui, Alejandro; Ortiz, Eduardo L.

    2005-01-01

    This is a detailed, day by day, account of Albert Einstein's activities, both social and scientific, during his 30-day stay in Argentina in 1925, including his lectures on relativity at the various local universities and his visit to the National Academy of Sciences, as follows from his personal Diary of the trip to South-America and other contemporary documents.

  6. ON THE PRESENCE OF PYRAMIODONTHERIUM (MAMMALIA, XENARTHRA, MEGATHERIIDAE IN THE LATE MIOCENE OF NORTHEASTERN ARGENTINA AND ITS BIOGEOGRAPHICAL IMPLICATIONS

    Directory of Open Access Journals (Sweden)

    DIEGO BRANDONI

    2009-03-01

    Full Text Available The biochron of the subfamily Megatheriinae, large to very large terrestrial sloths typified by Megatherium Cuvier, in Argentina extends from the middle Miocene of Patagonia to the late Pleistocene-early Holocene. Megatheriines reached their highest diversity in the lower levels (="conglomerado osífero", late Miocene of the Ituzaingó Formation in Entre Ríos Province, northeastern Argentina. Among the four megatheriines that occur in this unit, the genera Promegatherium Ameghino, Eomegatherium Kraglievich and Pliomegatherium Kraglievich represent relatively small to medium-sized taxa. Here we describe new material assigned to Pyramiodontherium, the largest of the four genera from the same bed and comparable in size to some Quaternary species of Megatherium. Three valid species of Pyramiodontherium have been recognized, all distributed mainly in northwestern Argentina, from the late Miocene in Catamarca Province (and probably also in Tucumán Province, and the late Pliocene in La Rioja Province. The presence of this genus in northeastern Argentina extends its known paleobiogeographical distribution. 

  7. Sediment records of highly variable mercury inputs to mountain lakes in Patagonia during the past millennium

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    M. Arribére

    2009-12-01

    Full Text Available High Hg levels in the pristine lacustrine ecosystems of the Nahuel Huapi National Park, a protected zone situated in the Andes of Northern Patagonia, Argentina, have initiated further investigations on Hg cycling and source identification. Here we report Hg records in sedimentary sequences aiming at identifying atmospheric sources during the past millennium. In addition to global transport and deposition, a potential atmospheric Hg source to be considered is the local emissions associated with volcanic activity, considering that the Park is situated in the Southern Volcanic Zone. Two sediment cores were extracted from Lake Tonček, a small, high-altitude system reflecting mainly direct inputs associated with atmospheric contributions, and Lake Moreno Oeste, a much larger and deeper lake having an extended watershed covered mostly by native forest.

    The sedimentary sequences were dated based on both 210Pb and 137Cs profiles. In addition, tephra layers were identified and geochemically characterized for chronological application and to investigate any association of volcanic eruptions with Hg records. Hg concentrations in sediments were measured along with 32 other elements, as well as organic matter, fossil chironomids, and biogenic silica. Observed background Hg concentrations, determined from the sequence domains with lower values, ranged from 50 to 100 ng g−1 DW (dry weight, whereas the surficial layers reached 200 to 500 ng g−1 DW. In addition to this traditional pattern, however, two deep domains in both sequences showed dramatically increased Hg levels reaching 400 to 650 ng g−1 DW; the upper dated to the 18th to 19th centuries, and the lower around the 13th century. These concentrations are not only elevated in the present profiles but also many-fold above the background values determined in other fresh water sediments, as were also the Hg fluxes, reaching 120 to 150

  8. Sediment records of highly variable mercury inputs to mountain lakes in Patagonia during the past millennium

    Directory of Open Access Journals (Sweden)

    S. Ribeiro Guevara

    2010-04-01

    Full Text Available High Hg levels in the pristine lacustrine ecosystems of the Nahuel Huapi National Park, a protected zone situated in the Andes of Northern Patagonia, Argentina, have initiated further investigations on Hg cycling and source identification. Here we report Hg records in sedimentary sequences to identify atmospheric sources during the past millennium. In addition to global transport and deposition, a potential atmospheric Hg source to be considered is the local emissions associated with volcanic activity, because the Park is situated in the Southern Volcanic Zone. Two sediment cores were extracted from Lake Tonček, a small, high-altitude system reflecting mainly direct inputs associated with atmospheric contributions, and Lake Moreno Oeste, a much larger and deeper lake having an extended watershed covered mostly by native forest.

    The sedimentary sequences were dated based on both 210Pb and 137Cs profiles. In addition, tephra layers were identified and geochemically characterized for chronological application and to investigate any association of volcanic eruptions with Hg records. Hg concentrations in sediments were measured along with 32 other elements, as well as organic matter, subfossil chironomids, and biogenic silica. Observed background Hg concentrations, determined from the sequence domains with lower values, ranged from 50 to 100 ng g−1 dry weight (DW, whereas the surficial layers reached 200 to 500 ng g−1 DW. In addition to this traditional pattern, however, two deep domains in both sequences showed dramatically increased Hg levels reaching 400 to 650 ng g−1 DW; the upper dated to the 18th to 19th centuries, and the lower around the 13th century. These concentrations are not only elevated in the present profiles but also many-fold above the background values determined in other fresh water sediments, as were also the Hg fluxes, reaching 120 to 150 μg m−2

  9. Evaluation of the Cerro Solo nuclear ore, province of Chubut. Geological characteristics of the deposit and of the basin. Pt. 2

    International Nuclear Information System (INIS)

    The Cerro Solo uranium ore deposit, is located 420 km west from Trelew city, Chubut province, in the extra-andean. The geologic environment belongs to the northwest edge portion of the intracratonic San Jorge Gulf Basin. The uraniferous district is named Pichinanes Ridge district. The mineralization lies 25 to 130 m depth, and is hosted by Los Adobes formation aged Aptian-Albian, made up by conglomerates, sandstones, coarse-sandstones and less abundant siltstones and claystones. The Cerro Solo ore deposit that belongs to the sandstone type-uranium occurrences are lenticular or tabular shaped, associated with organic material and pyrite, generally roughly parallel to the bedding (Trend-Type). The uranium minerals are uraninite and coffinite associated with organic material and pyrite, and frequently hematite, goethite, calcite, siderite and barite are observed. (Author)

  10. 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.

  11. Vajilla para la gastronomía de la Patagonia

    OpenAIRE

    Rodandelli, Julieta

    2012-01-01

    La Patagonia es una de las reglones más ricas del país, con atractivos turísticos que la hacen reconocida lnternacionalmente. La comida forma parte de su cultura, refleja su identidad. Hoy en día, la gastronomía expandió su mercado y se especializa en comidas típicas de diferentes etnias y regiones. Por esta razón, al proponer como proyecto el desarrollo de una linea de vajilla, la primera pregunta que surgió fue: ¿existe una asociación entre la comida típica de la región y los utensilios en ...

  12. Quantifying mass balance processes on the Southern Patagonia Icefield

    DEFF Research Database (Denmark)

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

    2015-01-01

    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...... 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...... 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...

  13. Helosis (Balanophoraceae) en Argentina Helosis (Balanophoraceae) in Argentina

    OpenAIRE

    José Luis Fontana; Orlando Fabián Popoff

    2006-01-01

    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 ilustra...

  14. 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. 

  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. 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.

  17. Procedencia de areniscas del Grupo Chubut en el área central de la Sierra de San Bernardo. Análisis preliminar

    Directory of Open Access Journals (Sweden)

    M.A. Tunik

    2004-12-01

    Full Text Available Se llevaron a cabo análisis petrográficos de detalle que permitieron determinar las modas detríticas en areniscas del Grupo Chubut con el fin de inferir el marco tectónico del área de aporte de las mismas. Sobre la base de las muestras estudiadas, se observan características petrográficas distintivas entre areniscas de las Formaciones Matasiete, Castillo y Bajo Barreal. La presencia de trizas dentro de las areniscas de las Formaciones Castillo y Bajo Barreal sugeriría una depositación concomitante con volcanismo de arco activo. El ploteo de las modas detríticas en diagramas de discriminación de ambiente de procedencia mostró una diferenciación entre las unidades del Grupo Chubut. La Formación Matasiete presenta una procedencia de arco magmático no disectado, mientras que las muestras correspondientes a las Formaciones Castillo y Bajo Barreal sugieren una procedencia de arco magmático transicional o disectado. Esto último sumado a la presencia de trizas de caída directa podría explicarse por la migración del arco volcánico hacia el oeste y a la exposición de las raíces del arco volcánico del Cretácico inferior por deformación en la faja plegada concomitante con un volcanismo activo ubicado hacia el oeste de la zona de estudio.

  18. Variabilidad interanual a interdecádica de la precipitación en Patagonia norte

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    Germán F Russián

    2010-12-01

    Full Text Available Se estudia la variabilidad interanual e interdecádica de la precipitación de verano y de invierno en la región norte de la Patagonia argentina, denominada Pampa Amarilla (RPA, para el período 1969-2006. El régimen anual muestra un marcado cambio del ciclo anual sobre una transecta noreste-sudoeste que atraviesa RPA. Hacia el noreste el ciclo anual de precipitación presenta los mayores registros, y muestra marcado mínimo invernal junto con máximo estival equinoccial (marzo. Hacia el sudoeste, los registros son menores, con uniforme distribución a lo largo del ciclo anual, presentando mínimos invernales ligeros. La distribución de frecuencia observada de las anomalías de precipitación, para verano e invierno, tienden a mostrar una mayor ocurrencia de frecuencias negativas en el intervalo (-100; 0mm, con una ligera mayor probabilidad de ocurrencia de extremos positivos. Las tendencias de las series del semestre cálido son positivas y significativas hacia el norte, con excepción en la zona centro. Para el semestre frío, las tendencias son positivas y significativas en el norte y sudeste de la RPA. Es posible caracterizar toda la RPA mediante dos índices de precipitación para verano e invierno, respectivamente. Estos índices de precipitación regional no presentan tendencia significativa. El verano puede subdividirse en dos subregiones, norte y sur, con diverso comportamiento interanual. En el norte los ciclos dominantes son de 5 años a 8 años; y en el sur, en las bandas 2-4 años, ca. 11 años y ca. 15 años. El invierno presenta una variabilidad interanual espacialmente homogénea con cuasi-ciclos significativos en torno a 4-5 años y 11 años. En ambas estaciones, los procesos de baja frecuencia de entre 2 y 6 años podrían estar relacionados al Modo Anular del Sur (MAS. El cuasi-ciclo solar podría estar involucrado también. Para veranos, la circulación troposférica de capas bajas, asociada a precipitación, también es

  19. Hantavirus reservoir Oligoryzomys longicaudatus spatial distribution sensitivity to climate change scenarios in Argentine Patagonia

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    González Paula LM

    2009-07-01

    Full Text Available Abstract Background Oligoryzomys longicaudatus (colilargo is the rodent responsible for hantavirus pulmonary syndrome (HPS in Argentine Patagonia. In past decades (1967–1998, trends of precipitation reduction and surface air temperature increase have been observed in western Patagonia. We explore how the potential distribution of the hantavirus reservoir would change under different climate change scenarios based on the observed trends. Methods Four scenarios of potential climate change were constructed using temperature and precipitation changes observed in Argentine Patagonia between 1967 and 1998: Scenario 1 assumed no change in precipitation but a temperature trend as observed; scenario 2 assumed no changes in temperature but a precipitation trend as observed; Scenario 3 included changes in both temperature and precipitation trends as observed; Scenario 4 assumed changes in both temperature and precipitation trends as observed but doubled. We used a validated spatial distribution model of O. longicaudatus as a function of temperature and precipitation. From the model probability of the rodent presence was calculated for each scenario. Results If changes in precipitation follow previous trends, the probability of the colilargo presence would fall in the HPS transmission zone of northern Patagonia. If temperature and precipitation trends remain at current levels for 60 years or double in the future 30 years, the probability of the rodent presence and the associated total area of potential distribution would diminish throughout Patagonia; the areas of potential distribution for colilargos would shift eastwards. These results suggest that future changes in Patagonia climate may lower transmission risk through a reduction in the potential distribution of the rodent reservoir. Conclusion According to our model the rates of temperature and precipitation changes observed between 1967 and 1998 may produce significant changes in the rodent

  20. Monitoreo ambiental de aguas superficiales y subterráneas, consideración de áreas sensibles, distrito uranífero Pichiñán Este, departamento Paso de Indios, provincia del Chubut

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    Humberto O Nievas

    2013-09-01

    Full Text Available En el ámbito de los estudios ambientales los sitios de localización de pobladores son considerados como áreas sensibles frente a una posible explotación del recurso uranífero. Se analiza la hidroquímica de los alrededores del distrito uranífero Pichiñán Este, sector central de la provincia del Chubut, por medio de un monitoreo que, desde el 2007, se realiza aplicando la metodología de muestreo de la comunidad europea. Se caracteriza la calidad del agua considerando elementos mayoritarios, minoritarios y trazas, estableciendo de esta manera sus potenciales usos. Estos resultados son informados a los pobladores y a la autoridad de control ambiental de la provincia del Chubut. Aunque, en general, la calidad del agua en cada punto de muestreo se mantiene relativamente constante, se observan variaciones naturales en los contenidos químicos.

  1. The Huillin in Argentina

    OpenAIRE

    Chehebar C.

    1986-01-01

    We recommend re-introduction of huillines in Lanin, Puelo and Los Alerces National Parks, through translocations of animals, so as to minimize the risks involved in the present dependence on Nahuel Huapi and Staten Island (as far as we know) for the conservation of the species in Argentina. Also, we recommend careful monitoring and protection of the Nahuel Huapi population and protection of the Staten Island ecosystems.

  2. Psychology In Argentina

    OpenAIRE

    Modesto M. Alonso

    2016-01-01

    A summary on Psychology as science and profession in Argentina is presented. The report includes a historical review on places, criteria and results of psychologists'education, aspects of their professional practices; quantitative data on universities, graduates and students related to sociodemographic variables; characteristics of research activities, publications, legal frameworks and types of institutions where psychologists work. Some distinctive features of Argentine psychology are menti...

  3. Apicultura en la Patagónia Argentina

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    L. Scatturice, R. Christiansen, L.Cañari.

    2005-04-01

    Full Text Available En la Patagonia Argentina la producción melífera, por debajo del paralelo 50 de latitud sur, con un clima, totalmente adverso, significa un verdadero desafío. La búsqueda de alternativas productivas, pensando una producción, con buena aceptación en el mercado y el aprovechamiento de ventajas comparativas como la imagen patagónica y la exigua contaminación ambiental. llevó a investigar la factibilidad de la producción melífera. El clima de la región, se viene contrarrestando fundamentalmente con genética, sanidad, y nutrición de las abejas, mas el ajuste minucioso del paquete tecnológico,Luego de 4 años de ensayos experimentales, se puede hablar de que la producción melífera es factible, optimizando al máximo todas las actividades del proceso productivo.

  4. Unexpected primitive rodents in the Quaternary of Argentina

    Science.gov (United States)

    Vucetich, María G.; Vieytes, Emma C.; Verzi, Diego H.; Noriega, Jorge I.; Tonni, Eduardo P.

    2005-10-01

    This article describes the first fossils recorded in the Hernandarias Formation (Pleistocene) in Entre Ríos province (eastern Argentina). They are represented by three teeth assigned to the caviomorph rodents (Rodentia, Mammalia) Aenigmys diamantensis gen. et sp. nov. and Eumysops. To establish the phylogenetic affinities of the two most enigmatic teeth, their enamel microstructure was studied. Aenigmys diamantensis is considered the most primitive taxon of a clade formed by Dinomyidae-Neoepiblemidae-Heptaxodontidae. Evidence of the close relationships among these families also is presented herein. The new fossils reinforce previous hypotheses about the survival of primitive Brazilian taxa after their extinction in the Pampas and Patagonia of southern South America. They also show that the diversity of caviomorph rodents during the Quaternary was greater than supposed and that an important Quaternary extinction, not previously detected, affected several lineages. With the available evidence, it is not possible to determine if these rodents indicate a warm pulse or a particular biogeographic situation in Entre Ríos.

  5. 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

  6. Distribución de macroinvertebrados (Plecoptera y Aeglidae en ecosistemas fluviales de la Patagonia chilena: ¿Muestran señales biológicas de la evolución geomorfológica postglacial? Distribution of macroinvertebrates (Plecoptera and Aeglidae in fluvial ecosystems of the Chilean Patagonia: Do they show biological signals of the postglacial geomorphological evolution?

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    CLAUDIO VALDOVINOS

    2010-06-01

    Full Text Available La Patagonia chilena incluye uno de los sistemas hídricos más complejos de Sudamérica y uno de los menos intervenidos del mundo, los cuales fueron intensamente modelados por la actividad glacial del Cuaternario. El objetivo de este estudio fue determinar si en esta área existen zonas de endemismo de macroinvertebrados bentónicos fluviales y analizar los patrones de diversidad de organismos de alta (Plecoptera y baja vagilidad (Aeglidae. Entre el 2006 y 2009 se muestrearon 183 sitios entre 42°50' y 54°43' S, focalizándose en las principales cuencas. Los muéstreos se realizaron con una red "kicknet", cubriendo una superficie de fondo de 8 m². En toda el área se registraron 30 especies de Plecoptera y dos de Aeglidae. Se identificó una zona de endemismo en la cuenca del río Aysén, sustentada por el plecóptero Ceratoperla fazi y el cangrejo Aegla neuquensis. Esta última especie correspondería a una población relictual procedente de los ríos de la estepa Argentina, que habría quedado atrapada en la Patagonia chilena, luego que se invirtiera el flujo del cauce del río que originalmente fluía hacia el Atlántico. Un marcado cambio latitudinal en la diversidad de especies fue evidente a lo largo del área de estudio (R² = 0.72, P The Chilean Patagonia includes one of the most complex hydrological systems of South America and one of the least modified systems of the world. These systems were intensely modified by the glacial activity of the Quaternary. The objectives of this study were to determine whether or not in this area exists zones of endemic benthic fluvial macroinvertebrates, and to analyze the patterns of diversity of species composed by organisms of high (Plecoptera and low (Aeglidae vagility. A collection of 183 selected sites, located between the latitude 42° 50' and 54°43' S, were sampled during 2006 and 2009. The sampling was focused on the main river basins and a "kicknet" was used to cover a surface of 8 m² at

  7. 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. PMID:24844168

  8. Case study - Argentina

    International Nuclear Information System (INIS)

    Antecedents and experience of nuclear activities in Argentina; the Atomic Energy Commission (CNEA). First development and research activities. Research reactors and radioisotopes plants. Health physics and safety regulations. - Feasibility studies for the first nuclear power plant. Awarding the first plant CNA I (Atucha I). Relevant data related to the different project stages. Plant performance. - Feasibility study for the second nuclear power plant. Awarding the second plant CNE (Central Nuclear Embalse). Relevant data related to established targets. Differences compared with the first station targets. Local participation. Plant performance. (orig./GL)

  9. 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.

  10. Estimating Hantavirus Risk in Southern Argentina: A GIS-Based Approach Combining Human Cases and Host Distribution

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    Veronica Andreo

    2014-01-01

    Full Text Available We use a Species Distribution Modeling (SDM approach along with Geographic Information Systems (GIS techniques to examine the potential distribution of hantavirus pulmonary syndrome (HPS caused by Andes virus (ANDV in southern Argentina and, more precisely, define and estimate the area with the highest infection probability for humans, through the combination with the distribution map for the competent rodent host (Oligoryzomys longicaudatus. Sites with confirmed cases of HPS in the period 1995–2009 were mostly concentrated in a narrow strip (~90 km × 900 km along the Andes range from northern Neuquén to central Chubut province. This area is characterized by high mean annual precipitation (~1,000 mm on average, but dry summers (less than 100 mm, very low percentages of bare soil (~10% on average and low temperatures in the coldest month (minimum average temperature −1.5 °C, as compared to the HPS-free areas, features that coincide with sub-Antarctic forests and shrublands (especially those dominated by the invasive plant Rosa rubiginosa, where rodent host abundances and ANDV prevalences are known to be the highest. Through the combination of predictive distribution maps of the reservoir host and disease cases, we found that the area with the highest probability for HPS to occur overlaps only 28% with the most suitable habitat for O. longicaudatus. With this approach, we made a step forward in the understanding of the risk factors that need to be considered in the forecasting and mapping of risk at the regional/national scale. We propose the implementation and use of thematic maps, such as the one built here, as a basic tool allowing public health authorities to focus surveillance efforts and normally scarce resources for prevention and control actions in vast areas like southern Argentina.

  11. Activities with Argentina

    International Nuclear Information System (INIS)

    In 1989, the US Department of Energy (DOE) responded to the need to redirect resources from weapons production to environmental restoration and waste management by establishing the Office of Environmental Management (EM) and delegated to this office the responsibility of cleaning up the US nuclear weapons complex. Now in its eight year, EM's mission has three central facets: (1) to assess, remediate, and monitor contaminated sites and facilities; (2) to store, treat, and dispose of waste from past and current operations; and (3) to develop and implement innovative technologies for environmental cleanup. To this end, EM has established domestic and international cooperative technology development programs, including one with the Republic of Argentina. Cooperating with Argentine scientific institutes and industries meets US cleanup objectives by: (1) identifying and accessing Argentine EM-related technologies, thereby leveraging investments and providing cost-savings; (2) improving access to technical information, scientific expertise, and technologies applicable to EM needs; and (3) fostering the development of innovative environmental technologies by increasing US private sector opportunities in Argentina in EM-related areas

  12. Modalidades y uso del material leñoso entre grupos cazadores-recolectores patagónicos (Argentina). Métodos y técnicas de estudio del material leñoso arqueológico

    OpenAIRE

    Caruso Fermé, Laura

    2012-01-01

    Este trabajo tiene por objetivo caracterizar las modalidades de adquisición y uso del recurso leñoso y establecer qué factores intervinieron en la organización de las mismas. En este sentido se pretende definir los criterios que rigieron la selección de este recurso, para ser utilizado como combustible y materia prima para la fabricación de instrumentos, por parte de las sociedades cazadoras-recolectoras que habitaron distintas zonas de la Patagonia (Argentina). Se entiende por modalidades de...

  13. Las especies de Leptohyphidae (Ephemeroptera de las yungas de Argentina y Bolivia: diagnosis, distribución y claves

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    Carlos MOLINERI

    2010-01-01

    Full Text Available Se estudiaron las especies de Leptohyphidae presentes en la selva de neblina de las yungas. Se conocen, de esta región, dieciocho especies en cinco géneros, incluyendo los siguientes nuevos registros: Leptohyphes liniti Wang, Sites & McCafferty, L. maculatus Allen, L. nigripennis Molineri & Zúñiga, L. setosus Allen y Tricorythodes hiemalis Molineri para Bolivia; Leptohyphes hirsutus Allen & Roback y L. petersi Allen para Bolivia y Argentina y Tricorythodes quizeri Molineri para Argentina. Se presentan diagnosis, ilustraciones y claves para distinguir todas las especies tratadas. El estudio de la distribución de las especies presentes en las yungas reveló tres grupos: 1 un grupo formado por cinco especies restringidas a las yungas, 2 un grupo de ocho especies que extienden sus rangos a través de selvas montanas hacia el norte y 3 un grupo de tres especies también presentes en otras áreas hacia el sur (centro de Argentina y norte de la Patagonia.

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

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    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.

  15. Rock Magnetic Properties of Laguna Carmen (Tierra del Fuego, Argentina): Implications for Paleomagnetic Reconstruction

    Science.gov (United States)

    Gogorza, C. G.; Orgeira, M. J.; Ponce, F.; Fernández, M.; Laprida, C.; Coronato, A.

    2013-05-01

    We report preliminary results obtained from a multi-proxy analysis including paleomagnetic and rock-magnetic studies of two sediment cores of Laguna Carmen (53°40'60" S 68°19'0" W, ~83m asl) in the semiarid steppe in northern Tierra del Fuego island, Southernmost Patagonia, Argentina. Two short cores (115 cm) were sampled using a Livingstone piston corer during the 2011 southern fall. Sediments are massive green clays (115 to 70 cm depth) with irregularly spaced thin sandy strata and lens. Massive yellow clay with thin sandy strata continues up to 30 cm depth; from here up to 10 cm yellow massive clays domain. The topmost 10 cm are mixed yellow and green clays with fine sand. Measurements of intensity and directions of Natural Remanent Magnetization (NRM), magnetic susceptibility, isothermal remanent magnetization, saturation isothermal remanent magnetization (SIRM), back field and anhysteretic remanent magnetization at 100 mT (ARM100mT) were performed and several associated parameters calculated (ARM100mT/k and SIRM/ ARM100mT). Also, as a first estimate of relative magnetic grain-size variations, the median destructive field of the NRM (MDFNRM), was determined. Additionally, we present results of magnetic parameters measured with vibrating sample magnetometer (VSM). The stability of the NRM was analyzed by alternating field demagnetization. The magnetic properties have shown variable values, showing changes in both grain size and concentration of magnetic minerals. It was found that the main carrier of remanence is magnetite with the presence of hematite in very low percentages. This is the first paleomagnetic study performed in lakes located in the northern, semiarid fuegian steppe, where humid-dry cycles have been interpreted all along the Holocene from an aeolian paleosoil sequence (Orgeira et el, 2012). Comparison between paleomagnetic records of Laguna Carmen and results obtained in earlier studies carried out at Laguna Potrok Aike (Gogorza et al., 2012

  16. 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.

  17. 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

    Directory of Open Access Journals (Sweden)

    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.

  18. 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

  19. 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

    OpenAIRE

    ESTEBAN G BALSEIRO; CLAUDIA P. QUEIMALIÑOS; BEATRIZ E. MODENUTTI

    2004-01-01

    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 di...

  20. 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.

  1. 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

    OpenAIRE

    MARIANO DEVOTO; DIEGO MEDAN

    2006-01-01

    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 f...

  2. Jurassic tetrapods and flora of Cañadón Asfalto Formation in Cerro Cóndor area, Chubut Province

    Directory of Open Access Journals (Sweden)

    Ignacio H. Escapa

    2008-12-01

    Full Text Available The plant and tetrapod fossil record of the Cañadón Asfalto Formation (Middle to Late Jurassic found in Cerro Cóndor area (Chubut Province is summarized here. The flora is dominated by conifers (Araucariaceae, Cupressaceae sensu lato but also includes ferns and equisetaleans. The tetrapod fauna is composed of dinosaur taxa described in the 70's as well as other remains recently described and other vertebrate groups such as amphibians, turtles, and mammals. The amphibian remains have been interpreted as representatives of a new species of Notobatrachus, considered one of the most basal members of the anuran lineage. Similarly, turtle remains have been recently recognized as a new species of basal turtle, bringing valuable information about the early evolution of this group. The dinosaur remains are largely dominated by saurischian taxa, represented by basal forms of Eusauropoda and Tetanurae. In addition, three different mammalian species have been identified and considered as early representatives of an endemic Gondwanan mammalian fauna. The fossil record of this formation represents the most completely known biota from the continental Middle to Late Jurassic of the Southern Hemisphere and one of the most complete of the entire world.

  3. 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.

  4. Operating practical experience at Argentina

    International Nuclear Information System (INIS)

    Operating experiences of Atucha-1 and Embalse Nuclear Power Plants were discussed in this work. The technical and economic aspects, such as reliability, availability, personnel training, operating costs, prices and market, which exercise influence upon Argentina nuclear energy policy, mainly on the power electric generation by nuclear power plants were considered. Finally the current status of the nucleoelectric sector in Argentina and forecasting were analysed

  5. A search for Potential Impact Sites in Southern Argentina

    Science.gov (United States)

    Rocca, M. C. L.

    The Southern part of Argentina is composed of five Provinces; Tierra del Fuego, Santa Cruz, Chubut, Rio Negro and Neuquen. A search for potential impact sites was performed by the author through the examination of 76 color LANDSAT satellite images ( 1:250,000 - resolution = 250 meters ) at the Instituto Geografico Militar ( IGM ) of Buenos Aires city. When a potential candidate was found a more detailed study of the site was done. If available the radar X-SAR satellite images of the Deutsche Forschungsanstalt fur Luft-und Raumfahrt, (DLR), Berlin, Germany , were also examined. The final step was to perform a review of the available published geologic information of each site at the Servicio Geologico y Minero Argentino ( SEGEMAR ), ( =Geological Survey of Argentina ), in Buenos Aires. The resulting catalogue contains information about sites where possible simple crater or complex impact structures could be present. Each case demands future detailed and `in situ' research by an impact cratering specialist. --Tierra del Fuego: TF1 ) Ushuaia 5569-II, No 218. Cerro Taarsh, Estancia San Justo. Possible complex structure. Semi-circular area of concentric low ridges. Estimated diameter : 12 km. Probably very eroded. --Santa Cruz: SC1 ) Gobernador Gregores 4969-I, No 127. Estancia La Aragonesa Possible eroded complex structure. Circular area of low ridges, estimated diameter: 10 km.. Bull's eye like morphology. SC2 ) Gobernador Gregores 4969-I, No 127. Gran Altiplanicie Central. Possible simple crater in basalts. Diameter: 1 km.. SC3 ) Tres Lagos 4972-IV, No 106. Meseta del Bagual Chico. Possible perfectly circular simple crater in basalts. Diameter: 1.0 km.. SC4 )Paso Rio Bote 5172-II, No 20. Rio Pelque, Ruta Provincial No 5. A circular bowl-shaped structure is present on fluvial deposits of pleistocenic age. Diameter: 3.5 km.. SC5 ) Caleta Olivia 4769-II, No 28. North of Cerro Doce Grande. Possible complex structure of concentric circular rings of ridges. SC6 ) Caleta

  6. 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

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

    NARCIS (Netherlands)

    Lenaerts, J.T.M.; van den Broeke, M.R.; van Wessem, J.M.; van de Berg, W.J.; 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 i

  8. gobierno dividido en Argentina

    Directory of Open Access Journals (Sweden)

    María Elisa Alonso García

    2008-01-01

    Full Text Available Este artículo es una reflexión sobre el gobierno dividido en Argentina, y un análisis sobre las consecuencias negativas que tiene el binomio presidencialismo –multipartidismo para la gobernabilidad y el desarrollo institucional del país. El estudio del caso argentino permite comprobar que el gobierno en minoría no constituye un obstáculo para el desarrollo institucional, y que los problemas que de él se derivan, como el bloqueo legislativo y el conflicto institucional pueden solventarse, evitando la crisis. En este sentido, se analiza el papel jugado por los partidos provinciales, que han sido determinantes para evitar los problemas vinculados con el gobierno dividido

  9. Soft rocks in Argentina

    Institute of Scientific and Technical Information of China (English)

    Giambastiani; Mauricio

    2014-01-01

    Soft rocks are a still fairly unexplored chapter in rock mechanics. Within this category are the clastic sedimentary rocks and pyroclastic volcanic rocks, of low to moderate lithification (consolidation, cemen-tation, new formed minerals), chemical sedimentary rocks and metamorphic rocks formed by minerals with Mohs hardness less than 3.5, such as limestone, gypsum, halite, sylvite, between the first and phyllites, graphitic schist, chloritic shale, talc, etc., among the latter. They also include any type of rock that suffered alteration processes (hydrothermal or weathering). In Argentina the study of low-strength rocks has not received much attention despite having extensive outcrops in the Andes and great impact in the design criteria. Correlation between geomechanical properties (UCS, deformability) to physical index (porosity, density, etc.) has shown promising results to be better studied. There are many studies and engineering projects in Argentina in soft rock geological environments, some cited in the text (Chihuído dam, N. Kirchner dam, J. Cepernic Dam, etc.) and others such as International Tunnel in the Province of Mendoza (Corredor Bioceánico), which will require the valuable contribution from rock mechanics. The lack of consistency between some of the physical and mechanical parameters explored from studies in the country may be due to an insufficient amount of information and/or non-standardization of criteria for testing materials. It is understood that more and better academic and professional efforts in improv-ing techniques will result in benefits to the better understanding of the geomechanics of weak rocks.

  10. Patrones geográficos de diferenciación craneofacial entre poblaciones de la región central del país y otras de Argentina: aportes desde la genética del paisaje

    Directory of Open Access Journals (Sweden)

    Mariana Fabra

    2008-09-01

    Full Text Available In this study we analyze the patterns of spatial variation of a population sample from the pre-Hispanicinhabitants of the central territory of Argentina (Córdoba and San Luis provinces archaeologically known as«Sierras Centrales», and 13 other samples from different ecological and geographical regions from Argentina.Additionally, we searched for the existence of genetic barriers in the geographic landscape. The study is based on10 craniometric measurements. Results from principal component analysis reveal that the pre-Hispanic inhabitantsof the Central Mountains of Argentina were biologically more related to the Patagonian groups than to thenortheast, central western and northwestern populations. Monmonier`s algorithm reveals that the pre-Hispanicinhabitants of the Central Mountains of Argentina were biologically more related to the Patagonian groups thanto the central and northern populations. These results support our hypothesis that the peopling of the centralregion of Argentina most likely took place as a migratory wave proceeding from the northeast, and continuedsouthward to Patagonia and Tierra del Fuego.

  11. Test de toxicidad sobre la especie Atriplex lampa, su aplicación para la evaluación de riesgo asociado a derrames de petróleo en suelos de la Patagonia

    Directory of Open Access Journals (Sweden)

    M Barquín

    2011-01-01

    Full Text Available Se estudiaron suelos contaminados con hidrocarburos del petróleo, en cercanías de la ciudad de Comodoro Rivadavia (Chubut, Argentina. Además de cuantificar el contenido de hidrocarburos totales en suelo (TPH, se realizaron bioensayos, utilizando especies vegetales como organismos de prueba. Los índices utilizados fueron: el porcentaje de germinación (G, la elongación de la radícula (R y del hipocotilo (H en Lactuca sativa L y dos especies autóctonas de la región patagónica, Atriplex lampa y Prosopis denudans. Se consideró, además, el efecto de la salinidad sobre los bioensayos, en base a la medición de la conductividad eléctrica del suelo (CE. Los resultados obtenidos del análisis por componentes principales, muestran que la primera componente explica el 58,3 % de la variabilidad total con un gradiente de toxicidad al cual contribuyen, principalmente, el porcentaje de germinación de Lactuca sativa L (GL y Atriplex lampa (GA, en este orden de significancia. La segunda componente explica el 16,9 % y la misma está caracterizada por TPH y CE. Además, no se ha encontrado una correlación simple y directa entre TPH y toxicidad, lo cual sugiere que TPH, en conjunción con ensayos ecotóxicos, parece ser una herramienta más adecuada para definir el punto final de una remediación. La especie autóctona Atriplex lampa mostró tener una sensibilidad similar a la especie Lactuca sativa L por lo que podría considerarse su utilidad como una especie fitoindicadora en las evaluaciones de riesgo ambiental.

  12. Moraine-dammed lake failures in Patagonia and assessment of outburst susceptibility in the Baker Basin

    Directory of Open Access Journals (Sweden)

    P. Iribarren Anacona

    2014-07-01

    Full Text Available Glacier retreat since the Little Ice Age has resulted in the development or expansion of hundreds of glacial lakes in Patagonia. Some of these lakes have produced large (≥106 m3 Glacial Lake Outburst Floods (GLOFs damaging inhabited areas. GLOF hazard studies in Patagonia have been mainly based on the analysis of short-term series (≤50 years of flood data and until now no attempt has been made to identify the relative susceptibility of lakes to failure. Power schemes and associated infrastructure are planned for Patagonian basins that have historically been affected by GLOFs, and we now require a thorough understanding of the characteristics of dangerous lakes in order to assist with hazard assessment and planning. In this paper, the conditioning factors of 16 outbursts from moraine dammed lakes in Patagonia were analysed. These data were used to develop a classification scheme designed to assess outburst susceptibility, based on image classification techniques, flow routine algorithms and the Analytical Hierarchy Process. This scheme was applied to the Baker Basin, Chile, where at least 7 moraine-dammed lakes have failed in historic time. We identified 386 moraine-dammed lakes in the Baker Basin of which 28 were classified with high or very high outburst susceptibility. Commonly, lakes with high outburst susceptibility are in contact with glaciers and have moderate (>8° to steep (>15° dam outlet slopes, akin to failed lakes in Patagonia. The proposed classification scheme is suitable for first-order GLOF hazard assessments in this region. However, rapidly changing glaciers in Patagonia make detailed analysis and monitoring of hazardous lakes and glaciated areas upstream from inhabited areas or critical infrastructure necessary, in order to better prepare for hazards emerging from an evolving cryosphere.

  13. Cambios globales e institucionales en política exterior: el caso del IIRSA, UNASUR y la patagonia argentina

    OpenAIRE

    Seitz, Ana Mirka

    2013-01-01

    La instalación del proyecto IIRSA, su perfil de toma de decisiones y sus objetivos, en el contexto de UNASUR para ser su Consejo de Infraestructura y Planificación instala lo dilemático del vínculo entre representación política y representación de intereses. La región lleva casi 50 años construyendo sus caminos de integración y resulta impactada por la lógica de la globalización, el mercado y el derrotado proyecto ALCA que se transforma, apareciendo parte de su lógica en el conjunto de proyec...

  14. Sources and distribution of aliphatic and polyaromatic hydrocarbons in coastal sediments from the Ushuaia Bay (Tierra del Fuego, Patagonia, Argentina).

    Science.gov (United States)

    Commendatore, Marta G; Nievas, Marina L; Amin, Oscar; Esteves, José L

    2012-03-01

    The environmental quality of Ushuaia Bay, located at the southernmost tip of South America, is affected by the anthropogenic pressure of Ushuaia city. In this study, levels and sources of hydrocarbons in coastal sediments were assessed. Aliphatic hydrocarbon fractions ranged between 5.5 and 1185.3 μg/g dry weight and PAHs from not detected to 360 ng/g. Aliphatic diagnostic indices, the nalkanes homologous series occurrence, Aliphatic Unresolved Complex Mixtures (AliUCMs), and pristane and phytane isoprenoids indicated a petrogenic input. Some sites showed biogenic features masked by the anthropogenic signature. Particularly in port areas biodegradation processes were evident. PAH ratios showed a mixture of petrogenic and pyrogenic sources. Aliphatic and aromatic UCMs were strongly correlated, reflecting chronic pollution. Three areas were distinguished inside the bay: (1) east, with low hydrocarbons impact; (2) central, where hydrocarbons accumulation was related to source proximity and sediment characteristics; (3) south-west, where sediment characteristics and current circulation favour hydrocarbons accumulation. PMID:22189069

  15. A new hedrurid species (Nematoda) from galaxiid fishes in Patagonia (Argentina) and infection of amphipods as intermediate host.

    Science.gov (United States)

    Brugni, Norma L; Viozzi, Gustavo P

    2010-02-01

    During a parasite survey of galaxiid fishes (Galaxiidae) from Patagonian Andean lakes, a new species of nematode, Hedruris suttonae n. sp. was collected from the stomach of the native Galaxias maculatus (Jenyns) and G. platei (Steindachner). Specimens were examined by light and scanning electron microscopy, especially head morphology, female caudal prehensile structure, and distribution of spines. The new species is distinguished by body and tail size, morphology and size of spicules, the arrangement of caudal papillae in the male, the female caudal hook, and size of eggs. Hyalella patagonica (Ortmann), a Neotropical species of Amphipoda, is reported as its natural intermediate host. Data regarding prevalence and mean intensity in the intermediate and definitive hosts are included. The diet and habitat of the hosts, the percentage of gravid females, the high values of prevalence, and mean intensity in galaxiid fishes, as well as the wide distribution of H. suttonae , collectively indicate that, in these oligotrophic Andean lakes, G. maculatus and G. platei are true definitive hosts of this nematode. PMID:19737026

  16. Tree-ring growth patterns and temperature reconstruction from Nothofagus pumilio (Fagaceae forests at the upper tree line of southern Chilean Patagonia Patrones de crecimiento arbóreo y reconstrucción de la temperatura en bosques de Nothofagus pumilio (Fagaceae en el límite arbóreo superior de la Patagonia austral de Chile

    Directory of Open Access Journals (Sweden)

    JUAN C. ARAVENA

    2002-06-01

    Full Text Available Nothofagus pumilio (Poepp. et Endl. Krasser is a deciduous species that dominates the upper tree line of the Chilean and Argentinean Andes between 35º 36' and 55º 31' S. In this study we describe the development of 21 tree-ring width chronologies of N. pumilio across its southernmost range of distribution (51-55º S in Chile, and analyze the relationship between N. pumilio tree-growth and climate. Ten of the tree-ring chronologies in our study, show an increasing trend and/or above average tree-ring growth since ca. 1960 to 1996, which coincides with the increase in temperatures shown by instrumental records from southern Patagonia. Another dominant pattern in tree-growth is a remarkable ca. 7-year cycle present in three of the study sites from Isla Navarino, the southernmost of our study areas (ca. 55º S. These two dominant tree-growth patterns, represent the main modes of variation of the N. pumilio tree-ring records in the southern Chilean Patagonia, accounting for 14 and 28 % of its total variance, respectively. Based on the positive correlation between tree growth and temperature in several of the study sites analyzed in this work, we developed a reconstruction of the Punta Arenas minimum annual temperatures from the seven tree-ring records with the highest correlation with temperature, covering the 1829-1996 period. The reconstruction shows that during most of the 19th century, minimum annual temperatures remained below-average and increased to values fluctuating around the mean during the 1900-1960 period, followed by a clear trend with above-average values after 1963Nothofagus pumilio (Poepp. et Endl. Krasser es una especie caducifolia que domina el límite arbóreo superior de los Andes de Chile y Argentina entre los 35º 36' y 55º 31' S. En este trabajo describimos el desarrollo de 21 cronologías de ancho de anillos de N. pumilio para su rango más austral de distribución (51-55º S en Chile, así como el análisis de su relaci

  17. 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

  18. 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

  19. Physically Based Mountain Hydrological Modelling using Reanalysis Data in Patagonia

    Science.gov (United States)

    Krogh, S.; Pomeroy, J. W.; McPhee, J. P.

    2013-05-01

    Remote regions in South America are often characterized by insufficient observations of meteorology for robust hydrological model operation. Yet water resources must be quantified, understood and predicted in order to develop effective water management policies. Here, we developed a physically based hydrological model for a major river in Patagonia using the modular Cold Regions Hydrological Modelling Platform (CRHM) in order to better understand hydrological processes leading to streamflow generation in this remote region. The Baker River -with the largest mean annual streamflow in Chile-, drains snowy mountains, glaciers, wet forests, peat and semi-arid pampas into a large lake. Meteorology over the basin is poorly monitored in that there are no high elevation weather stations and stations at low elevations are sparsely distributed, only measure temperature and rainfall and are poorly maintained. Streamflow in the basin is gauged at several points where there are high quality hydrometric stations. In order to quantify the impact of meteorological data scarcity on prediction, two additional data sources were used: the ERA-Interim (ECMWF Re-analyses) and CFSR (Climate Forecast System Reanalysis) atmospheric reanalyses. Precipitation temporal distribution and magnitude from the models and observations were compared and the reanalysis data was found to have about three times the number of days with precipitation than the observations did. Better synchronization between measured peak streamflows and modeled precipitation was found compared to observed precipitation. These differences are attributed to: (i) lack of any snowfall observations (so precipitation records does not consider snowfall events) and (ii) available rainfall observations are all located at low altitude (<500 m a.s.l), and miss the occurrence of high altitude precipitation events. CRHM parameterization was undertaken by using local physiographic and vegetation characteristics where available and

  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. Physically Based Mountain Hydrological Modelling using Reanalysis Data in Patagonia

    Science.gov (United States)

    Krogh, S.; Pomeroy, J. W.; McPhee, J. P.

    2013-05-01

    Remote regions in South America are often characterized by insufficient observations of meteorology for robust hydrological model operation. Yet water resources must be quantified, understood and predicted in order to develop effective water management policies. Here, we developed a physically based hydrological model for a major river in Patagonia using the modular Cold Regions Hydrological Modelling Platform (CRHM) in order to better understand hydrological processes leading to streamflow generation in this remote region. The Baker River -with the largest mean annual streamflow in Chile-, drains snowy mountains, glaciers, wet forests, peat and semi-arid pampas into a large lake. Meteorology over the basin is poorly monitored in that there are no high elevation weather stations and stations at low elevations are sparsely distributed, only measure temperature and rainfall and are poorly maintained. Streamflow in the basin is gauged at several points where there are high quality hydrometric stations. In order to quantify the impact of meteorological data scarcity on prediction, two additional data sources were used: the ERA-Interim (ECMWF Re-analyses) and CFSR (Climate Forecast System Reanalysis) atmospheric reanalyses. Precipitation temporal distribution and magnitude from the models and observations were compared and the reanalysis data was found to have about three times the number of days with precipitation than the observations did. Better synchronization between measured peak streamflows and modeled precipitation was found compared to observed precipitation. These differences are attributed to: (i) lack of any snowfall observations (so precipitation records does not consider snowfall events) and (ii) available rainfall observations are all located at low altitude (Canada. Some soil moisture parameters were calibrated from streamflow observations. Model performance was estimated through comparison with observed streamflow records. Simulations using observed

  2. 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

    Directory of Open Access Journals (Sweden)

    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

  3. Occupational health in Argentina.

    Science.gov (United States)

    Werner, A F

    2000-07-01

    Argentina is within the denominated "new industrialised countries", with the characteristic of having high contrasts in the urban population, based on service and industry, and in the rural population, based on agriculture and cattle, still the main sources of wealth in the country. The process of globalisation and the need to compete hard in international markets have provoked high unemployment and the transfer of workers from a formal market to an informal one. Legislation on occupational health is old and it is in the process of being updated. The system of prevention, assistance and compensation for accidents at work and for occupational illnesses has changed from being optative for employers, to the compulsory hiring of private insurance companies. The Government keeps the role of supervisor of the system. There are enough professionals in occupational health, hygiene and safety but not occupational nurses. The teaching is given by many universities and professional associations, some of which have an active profile in the occupational health of the country. PMID:10963410

  4. Postfire encroachment of Fabiana imbricata is real? Assessing changes of shrubland occupation during 40 years in NW Patagonia steppe

    Science.gov (United States)

    Lasaponara, Rosa; Oddi, Facundo; Ghermandi, Luciana

    2014-05-01

    Landscapes are dynamic in space and time, being spatio-temporal processes of particular interest for landscape ecology. In particular, grasslands can change their structure through the expansion of shrubs in the landscape matrix. Shrub encroachment affect biodiversity as well as forage availability that is the key component of the productive use of rangelands. However, despite its recognition as a global problem, knowledge on the rates, dynamics and encroachment patterns is even scarce. For example, although it is generally accepted that fire control shrub encroachment, certain shrubby species could be favored by the occurrence of fire. In northwestern Patagonian steppe, Fabiana imbricata form large monospecific shrublands that are part of the landscape mosaic and its dynamics of regeneration is strongly related to fire. This long-lived shrub (≡ 150 years) is a typical seeder that is killed by fire and recruits seedlings almost exclusively in post-fire, establishing even-age patches. Our objective was to determine whether F. imbricata shrublands have expanded during the last 40 years in a landscape fire prone. The study area corresponds to San Ramon ranch (22,000 ha) located in northwestern Patagonia steppe, Argentina (latitude -41° 04'; longitude -70° 51'). Two distribution maps of the species were made that corresponds to the study area in 1968 and 2011. The 1968 map was elaborated from the digitalization of aerial photographs (1:45000) while the 2011 map was produced with very high resolution satellite images, current aerial photographs and GPS field data. Both maps were loaded into a GIS environment, in which landscape metrics at patch and class level were determined and then compared. From remote sensing and dendroecological techniques, we know that the study area was almost entirely affected by fires during the study period. Therefore, the comparison of both maps allows us to know post-fire changes in the shrublands spatial configuration at the landscape

  5. 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

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

    International Nuclear Information System (INIS)

    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 δ13C 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 (−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 δ13C 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: ► Pelagic allochthonous indicators were detected in two Patagonian

  7. 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

    Directory of Open Access Journals (Sweden)

    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

  8. Hungry China Shops in Argentina

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    @@ Chinese investment is flooding into Argentina as the Asian giant expands its global commodity hunt from the raw materials used in industry to the foodstuffs needed to feed its 1.3 billion citizens. China's investment in Latin America hit USI15.6 billion during the 12-month period through the end of May, nearly three times greater than the year-ago period, consulting firm Deloitte said in a report.Of that amount, Brazil received about 60% and Argentina close to 40%.

  9. Tick paralysis cases in Argentina

    Directory of Open Access Journals (Sweden)

    Carlos Remondegui

    2012-08-01

    Full Text Available Tick paralysis (TP occurs worldwide and is caused by a neurotoxin secreted by engorged female ticks that affects the peripheral and central nervous system. The clinical manifestations range from mild or nonspecific symptoms to manifestations similar to Guillain-Barré syndrome, bulbar involvement, and death in 10% of the patients. The diagnosis of TP is clinical. To our knowledge, there are no formal reports of TP in humans in South America, although clusters of TP among hunting dogs in Argentina have been identified recently. In this paper, clinical features of two cases of TP occurring during 1994 in Jujuy Province, Argentina, are described.

  10. 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.

  11. Investigación geohidrológica en un sector de Península Valdés, provincia de Chubut

    OpenAIRE

    Álvarez, María del Pilar

    2010-01-01

    La zona de estudio pertenece a la región septentrional de la Patagonia extrandina, se localiza en el sector Sur de la Península Valdés entre los paralelos 42º 32’ S y 42º 53’ S y los meridianos 63º 34’ W y 64º 22’ W, cubriendo una superficie de 1700 km2 y está delimitada al Norte por una divisoria de aguas subterráneas, al Oeste por el Golfo Nuevo y al Sur y Este por el Océano Atlántico. El régimen climático es de tipo árido mesotermal, con precipitaciones pluviales que apenas superan los ...

  12. The late Oligocene flora from the Río Leona Formation, Argentinian Patagonia

    OpenAIRE

    Césari, Silvia N.; Panti, Carolina; Roberto R Pujana; Francis, Jane E.; Sergio A Marenssi

    2015-01-01

    A late Oligocene plant macrofossil assemblage is described from the Río Leona Formation, Argentinian Patagonia. This includes a fern, “Blechnum turbioensis” Frenguelli, one species of conifer, and sixteen angiosperm taxa. Rosaceae, Myrtaceae, Proteaceae, Lauraceae, Anacardiaceae and Typhaceae are represented by one species in each family. Five species are considered to be members of the Fabales. Three leaf taxa together with Carpolithus seeds are placed in the Nothofagaceae. Palynomorphs and ...

  13. Food habits of the great horned owl in northwestern Argentine Patagonia: the role of introduced lagomorphs

    OpenAIRE

    Donázar, José A.; Travaini, Alejandro; Ceballos, Olga; Delibes, M.; Hiraldo, F.

    1997-01-01

    —Pellets of adult and nestling Great Horned Owls (Bitho tirginianus) were collected at 12 owl territories nearJunin de los Andes (Neuquen, Argentine Patagonia) during the breeding seasons of 1991— 92 and 1994—95. Mammals represented 69% of the total prey items (N = 1324) identified and Reithrodon auritus (16%), Lepuseuwpaeus (12%) and Ctenomys haigi (12%) were the most common species. Anhropods aecounted for 27% of the total prey by numbers. The two main prey items b...

  14. Paisajes del agua y trayectorias del arraigo en la Patagonia chilena

    OpenAIRE

    Muñoz Rebolledo, Mª Dolores

    2011-01-01

    El artículo analiza las dificultades de asentarase en los paisajes de la vastedad en la Patagonia chilena, en la zona del río Baker y lago General Carrera. Toma como referencia la definicíión de paisaje contenida en el marco teórico y otros antecedentes expuestos en el capítulo 2 de la tesis doctoral

  15. 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.

  16. Estado nutricional infanto juvenil en seis provincias de Argentina: variación regional

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    Oyhenart, Evelia Edith

    2008-01-01

    Full Text Available En Argentina si bien se dispone de información de prevalencias de malnutrición (desnutrición y exceso de peso, existe dificultad en la comparación debido a que en la mayor parte de los casos hay disparidad en las técnicas y/o metodologías empleadas. El objetivo del presente trabajo es analizar el estado nutricional de la población infanto-juvenil de seis provincias: Buenos Aires (Brandsen y La Plata, Catamarca (Catamarca, Chubut (Puerto Madryn, Jujuy (San Salvador de Jujuy, La Pampa (Santa Rosa y Toay y Mendoza (General Alvear, empleando la misma metodología de estudio a fin de disponer de elementos diagnósticos que permitan su contrastación. Se midieron, en el período 2003-2005, peso corporal (kg y talla (cm en una muestra de 15011 escolares asistentes a 102 establecimientos escolares comprendidos entre los 3 y 18 años de edad. Con los datos obtenidos se analizaron los indicadores Talla/Edad, Peso/Talla, Peso/Edad e Indice de Masa Corporal (IMC. Los indicadores de desnutrición fueron comparados con los valores de referencia provenientes del NCHS y las prevalencias de baja talla para la edad (BT/E, bajo peso para la talla (BP/T y bajo peso para la edad (BP/E se calcularon tomando como punto de corte el percentilo 5 de dicha referencia. Para sobrepeso (S y obesidad (O se tomaron puntos de corte proyectados sobre los valores adultos de 25 y 30 Kg/m2 según edad y sexo propuestos por la referencia Internacional Obesity Task Force. A fin de disponer de información socio-ambiental de las zonas de estudio se analizaron indicadores demográficos, económicos, sociales y ambientales. Cuando fue posible, se utilizaron los datos provenientes del Censo Nacional de Población y Vivienda (CNPyV 2001, de las Encuestas Permanentes de Hogares (EPH, INDEC, de la Dirección de Estadísticas de Salud del Ministerio de Salud de la Nación (DEIS, MSyA y de otros organismos oficiales. Las prevalencias generales de desnutrición (BT/E, BP/T y BP/E y

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

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    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.

  18. Deterioro ambiental y micromamíferos durante el Holoceno en el nordeste de la estepa patagónica (Argentina Environmental deterioration and micromammals during the Holocene in northeastern Patagonian steppe (Argentina

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    ULYSES F. J. PARDIÑAS

    2000-03-01

    Full Text Available Se estudió la composición taxonómica cualitativa y cuantitativa de una muestra de micromamíferos proveniente del paraje Lle cul (43º 20' S, 65º 35' W, en el valle del río Chubut (Argentina, con una antigüedad de 1830 ± 70 años radiocarbónicos AP. La asociación está integrada por roedores sigmodontinos (6 especies, caviomorfos (dos especies, quirópteros (dos especies y marsupiales marmosinos (dos especies, destacándose por su abundancia Calomys cf. C. laucha-C. musculinus (35,2% y Eligmodontia sp. (33,4%. El estudio de la frecuencia esqueletaria y marcas de corrosión sobre los restos óseos indican que el agregado ha sido generado por una estrigiforme poco destructiva, quizás Tyto alba, y depositado probablemente en época invernal. La comparación con los micromamíferos de una muestra actual de egagrópilas de T. alba de la misma localidad (correspondiente a un año, revela una disminución importante en la diversidad específica, con una dominancia cercana al 95% para Calomys cf. C. laucha-C. musculinus. La discusión efectuada a base de muestras actuales representativas de diferentes distritos fitogeográficos patagónicos y evidencias paleoambientales para el Holoceno superior, indican como causas más probables de este empobrecimiento al impacto antrópico durante los últimos 100 años. Actividades como la expansión de agroecosistemas habrían favorecido la dispersión y abundancia de Calomys en detrimento de otros micromamíferosThe qualitative and quantitative taxonomic composition of a micromammal sample from Lle cul (43º 20' S, 65º 35' W, in the lower valley of the Chubut River (Argentina, was analyzed. The age of the sample was 1,830 ± 70 yr BP. The association includes 6 species of sigmodontine rodents, two species of caviomorphs, two species of chiropterans, and two species of marmosine marsupials, including Calomys cf. C. laucha-C. musculinus (35.2% and Eligmodontia sp. (33.4% as the most abundant taxa. The

  19. 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.

  20. IMÁGENES DE AUTOR E IMÁGENES DE PATAGONIA: TRELEW DE MARCELO ECKHARDT Images of author and images of Patagonia: Trelew by Marcelo Eckhardt

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    Luciana Andrea Mellado

    2010-12-01

    Full Text Available Trelew (1997 del escritor argentino Marcelo Eckhardt está compuesto por ensayos, relatos y una novela que se desarrollan de modo intercalado. Caracterizado por la mixtura genérica, así como por una insistente descripción del espacio geográfico y cultural de PatagoniaTrelew despliega la mitografía de la ciudad homónima a la vez que construye la del propio autor que expande y diversifica su enunciación en otras voces, convirtiendo el texto en un texto plural no sólo en cuanto a las formas sino, también, en cuanto a las voces que lo configuran.Trelew (1997 of the Argentine writer Marcelo Eckhardt is composed by essays, stories and a novel that they develop in an inserted way. Characterized by the generic mixture, and by a insistent description of the geographic and cultural space of the Patagonia, Trelew develops the mitografìa of the city homonym simultaneously that constructs that of the own author who expands and diversifies his speech in other voices, turning the text in a plural text by the forms and by the voices that form it.

  1. 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

  2. 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

  3. Occurrence of Hirudinea species in a post urban reach of a Patagonian mountain stream

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    M. Laura Miserendino

    2014-09-01

    Full Text Available Temporal (May 2005 to February 2006 and habitat distribution (pools and riffles of Hirudinea species was analyzed at a post urban reach from Esquel stream (Chubut province, Patagonia, Argentina. Site was located 5.7 km downstream a Waste Treatment Plant. Mean values of nutrients: ammonia, nitrates and soluble reactive phosphate, as well water conductivity, turbidity and total suspended solids indicated physical and organic pollution. Leeches assemblage was composed by the glossiphonids: Helobdella scutifera Blanchard, 1900, H. michaelseni (Blanchard, 1900, H. simplex (Moore, 1911, Helobdella sp., H. hyalina Ringuelet, 1942, H. obscura Ringuelet, 1942 and the semiscolecid Patagoniobdella variabilis (Blanchard, 1900. From these H. hyalina and H. obscura are new records for Chubut province. Helobdella hyalina (810 ind.m-2 and H. simplex (465 ind. m-2 clearly dominated the assemblage at the reach. Only H. simplex displayed a spatial preference being significantly more abundant in pools than in riffle habitats (p<0.001. Species recruitment occurred mostly at September, December and March when juveniles were very abundant. Although several species of Helobdella were able to live in the disturbed section of the stream, only H. simplex and H. hyalina sustained large populations at the site and can be considered as tolerant to organic enrichment. This information is valuable to future studies on stream condition assessment in mountainous areas in Patagonia, and in other areas in which these species are present.

  4. Pathology of Haplosporidium patagon affecting siphonariid gastropods in Patagonia.

    Science.gov (United States)

    Di Giorgio, Gisele; Gilardoni, Carmen; Ituarte, Cristián

    2014-11-13

    Haplosporidium patagon was found parasitizing Siphonaria lessonii and S. lateralis, 2 siphonariid gastropods co-occurring on the littoral rocky shore at Puerto Deseado, Santa Cruz, Argentina. Gastropods from 2 habitats representing 2 different levels of environmental harshness were studied. In both cases, S. lessonii showed a higher prevalence of infection (3.78%) over the entire 14 mo study period than S. lateralis (0.13%). Very different values of prevalence of infection were observed at the different sampling sites: Site 1, the more restrictive habitat (exposed for long periods to desiccation during low tides, higher ultraviolet exposure, and high ranges of temperature variation) showed a higher prevalence value (5.99%) than Site 2 (1.46%). Statistical differences in prevalence were also found between values corresponding to the austral spring (3.35% at Site 1 and 0.74% at Site 2) and winter (13.79% at Site 1 and 2.13% at Site 2). The presence/absence of H. patagon did not vary significantly with gastropod shell length. Infection affected the digestive gland, whose normal histology was greatly modified. The hermaphroditic gonads were also affected; the female germinal cells disappeared or only a few primary or previtellogenic oocytes were present, and vitellogenesis was inhibited. The function of the male germinal epithelium, as well as spermatogenesis and spermiogenesis processes and associated organs (seminal vesicles and seminal receptacles), were not affected. However, the glandular pallial complex of the reproductive systemwas affected, and we observed a significant reduction in development in parasitized gastropods. H. patagon sporocysts also invaded the supporting connective tissues of both the kidney and pseudobranch. PMID:25392043

  5. Pathology of Haplosporidium patagon affecting siphonariid gastropods in Patagonia.

    Science.gov (United States)

    Di Giorgio, Gisele; Gilardoni, Carmen; Ituarte, Cristián

    2014-11-13

    Haplosporidium patagon was found parasitizing Siphonaria lessonii and S. lateralis, 2 siphonariid gastropods co-occurring on the littoral rocky shore at Puerto Deseado, Santa Cruz, Argentina. Gastropods from 2 habitats representing 2 different levels of environmental harshness were studied. In both cases, S. lessonii showed a higher prevalence of infection (3.78%) over the entire 14 mo study period than S. lateralis (0.13%). Very different values of prevalence of infection were observed at the different sampling sites: Site 1, the more restrictive habitat (exposed for long periods to desiccation during low tides, higher ultraviolet exposure, and high ranges of temperature variation) showed a higher prevalence value (5.99%) than Site 2 (1.46%). Statistical differences in prevalence were also found between values corresponding to the austral spring (3.35% at Site 1 and 0.74% at Site 2) and winter (13.79% at Site 1 and 2.13% at Site 2). The presence/absence of H. patagon did not vary significantly with gastropod shell length. Infection affected the digestive gland, whose normal histology was greatly modified. The hermaphroditic gonads were also affected; the female germinal cells disappeared or only a few primary or previtellogenic oocytes were present, and vitellogenesis was inhibited. The function of the male germinal epithelium, as well as spermatogenesis and spermiogenesis processes and associated organs (seminal vesicles and seminal receptacles), were not affected. However, the glandular pallial complex of the reproductive systemwas affected, and we observed a significant reduction in development in parasitized gastropods. H. patagon sporocysts also invaded the supporting connective tissues of both the kidney and pseudobranch.

  6. 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.

  7. LUIS SEPÚLVEDA: UN VIAJE EXPRESS AL CORAZÓN DE LA PATAGONIA Luis Sepúlveda: an express travel to Patagonia’s heart

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    Silvia Casini

    2004-12-01

    Full Text Available En este artículo se analizan las formas de representación de la Patagonia en la novela Patagonia Express de Luis Sepúlveda. Con mucho de intertextualidad y algo de novela sentimental, los relatos de viaje del escritor chileno en los que aparece la Patagonia están armados como narraciones por espacios de la imaginación destinados a seducir al lector para instalarlo en un espacio misterioso, mitad legendario, mitad histórico, trazando un recorrido apasionado con el que logra un vínculo empático muy fuerte con el lector. Nuestra hipótesis es que el de Patagonia Express no es un espacio aferrado al referente sino que lo que interesa es re-visitar y revitalizar una matriz legendaria y textual ya existente sobre la Patagonia. Por ese apego a lo construido literariamente, al describir el referente, el relato se deja influir por los estereotipos del texto fundador.This article will analyze forms of representation of the Patagonia in the novel Patagonia Express by the Chilean author Luis Sepulveda. Characterized by intertextuality as well as aspects of the sentimental novel, these travel tales of the Patagonia are structured as narratives by spaces of the imagination. These spaces are designed to seduce the reader, installing him in a mysterious space, both legendary and historical; whose passionate exploration will create a strong bond between text and reader. Our hypothesis is that the Patagonia of Patagonia Express is not a space established by its referent; rather, the emphasis is upon revisiting and revitalizing originative legends and texts. Because of this attachment to literary constructions, descriptions of the referent allow the reader to be influenced by stereotypes of the foundational text.

  8. Exploration for uranium in Argentina: New policies of reactivation

    International Nuclear Information System (INIS)

    Full text: The policy established by the National Government of Argentina in August 2006 related to resuming the Nuclear activity in the country, lead the CNEA trough the Exploration of Raw Materials Manager (ERMM) to establish working strategies for the next 10 years. These strategies together with the assignment of an adequate budget will contribute to define new uranium resources, which together with the already known ones, will be used to supply the requirements of Nuclear Power and Research Plants in the future. Thus, the ERMM is applying a policy of human resources hiring new personnel in order to count with the minimum necessary workforce to reach these tasks. In Argentina known U resources are related to sedimentary, igneous and metamorphic environments. Considering the geology of the different regions, Argentina has been divided into 57 units in which the geological, geochemical, mineralogical and structural information is evaluated in order to estimate the uranium geological favorability of each unit. The final pursuit of this regional study is to circumscribe new areas with anomalous uranium contents in which prospection and exploration should be carried out. These studies together with prospection and exploration works are performed in the country by four exploration centers based in Salta (RN), Cordoba (R.Ce), Mendoza (R.Cu) and Trelew (RP). The works planned for each exploration center includes: Regional Noroeste, Mina Franca Deposit: peri-granitic vein- type mineralization: 25% of surface exploration has been performed. Mineralized areas: Istataco and San Buenaventura correspond to an igneous-metamorphic environment, Sierra de Vaqueria to a sedimentary one: Prospection stage. Regional Centro, Mineralized areas: El Gallo: drilling stage and Donato: prospection stage, correspond to an igneous-metamorphic environment with intra and peri-granitic anomalies. Noya: prospection stage, sedimentary environment. Regional Cuyo, Mineralized area: Western Sierra

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

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    Núñez Paula Gabriela

    2013-12-01

    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.Palabras clave: urbanización simbólica, xenofobia, turismo, religión, San Carlos de Bariloche.Urban Marks and Social Senses at Issue. San Carlos de Bariloche, 1966-1983AbstractSan Carlos de Bariloche is the main tourist town in the Argentinean Patagonia. It is also the biggest city in the Province of Río Negro, and the third largest in Patagonia. Its demographic growth has been nurtured by national and international migrations, the most

  10. Trace elements have limited utility for studying migratory connectivity in shorebirds that winter in Argentina

    Science.gov (United States)

    Torres-Dowdall, J.; Farmer, A.H.; Abril, M.; Bucher, E.H.; Ridley, I.

    2010-01-01

    Trace-element analysis has been suggested as a tool for the study of migratory connectivity because (1) trace-element abundance varies spatially in the environment, (2) trace elements are assimilated into animals' tissues through the diet, and (3) current technology permits the analysis of multiple trace elements in a small tissue sample, allowing the simultaneous exploration of several elements. We explored the potential of trace elements (B, Na, Mg, Al, Si, P, S, K, Ca, Ti, Cr, Mn, Ni, Cu, Zn, As, Sr, Cs, Hg, Tl, Pb, Bi, Th, and U) to clarify the migratory connectivity of shorebirds that breed in North America and winter in southern South America. We collected 66 recently replaced secondary feathers from Red Knots (Calidris canutus) at three sites in Patagonia and 76 from White-rumped Sandpipers (C. fuscicollis) at nine sites across Argentina. There were significant differences in trace-element abundance in shorebird feathers grown at different nonbreeding sites, and annual variability within a site was small compared to variability among sites. Across Argentina, there was no large-scale gradient in trace elements. The lack of such a gradient restricts the application of this technique to questions concerning the origin of shorebirds to a small number of discrete sites. Furthermore, our results including three additional species, the Pectoral Sandpiper (C. melanotos), Wilson's Phalarope (Phalaropus tricolor), and Collared Plover (Charadrius collaris), suggest that trace-element profiles change as feathers age. Temporal instability of trace-element values could undermine their application to the study of migratory connectivity in shorebirds. ?? The Cooper Ornithological Society 2010.

  11. Hilvanando opuestos: lecturas identitarias a partir de la conformación de una comunidad mapuche en Lago Puelo, Provincia de Chubut

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    Alma Tozzini

    2007-03-01

    Full Text Available El incremento de los negocios inmobiliarios que se viene dando en Patagonia en forma sostenida desde los '90 impacta fuertemente en Lago Puelo sobre los reclamos de tenencia de la tierra de descendientes de antiguos pobladores llegados a la región a fines del S. XIX. El siguiente artículo se propone analizar desde una perspectiva turneriana, y a partir de la reciente conformación de una Comunidad Mapuche en la localidad, como se relacionan las luchas por la tenencia de la tierra, la identidad étnico - nacional de los actores en pugna y el rol jugado por el Estado provincial y local vía su política territorial. Analizar dichos sucesos en clave de "drama social" nos permitirá no sólo comprender las diferentes etapas que se vienen dando en esta lucha ya centenaria, sino proveer de un marco desde el cual repensar, a partir del análisis de esta pequeña localidad, la historia "oficial" de las identidades de los pueblos cordilleranos.The supported increase in real - estate business in Patagonia since the decade of 1990, has a strong impact in Lake Puelo on the claims to possession of the land of descendants of former settlers came to the region at the end of the nineteenth century. The following article proposes to analyse from a turnerian perspective, and starting from the recent conformation of a Mapuche Community in the area, how the struggles for possession of the land, the ethnic - national identity of the involved actors and the role played by the provincial and local State through its territorial politics are related to one another. To analyse these events in key of "social dramas" will allow us not only to understand the different stages that had been occurring in this centenarian struggle but also will provide us with a frame from which rethink, starting from the analysis of this small area, the "official" story of the identities of the people of the (Andes mountain chain.

  12. Home Financing Institutions in Argentina

    OpenAIRE

    Marcela Cristini; Ramiro Moya

    2004-01-01

    (Available only in Spanish) This work analyses the case of the deepening of mortgage lending in Argentina in the 1990s and compares it with the failure of the 1980s. It shows that macroeconomic stability determines the development of the market and that a rapid takeoff can be achieved with the appropriate legal and market institutions (competition between banks and dollar contracts). The real price of property, and unemployment influence the performance of the market, which expands at the rat...

  13. 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.

  14. Mapuche y ranqueles en la Argentina: relatos sobre su pasado y presente

    Directory of Open Access Journals (Sweden)

    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.

  15. Discursos de alteridad en la dramaturgia regional de la posdictadura argentina

    Directory of Open Access Journals (Sweden)

    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.

  16. Jurassic tetrapods and flora of Cañadón Asfalto Formation in Cerro Cóndor area, Chubut Province Flora y tetrápodos del Jurásico de la Formación Cañadón Asfalto en el área de Cerro Cóndor, provincia de Chubut

    Directory of Open Access Journals (Sweden)

    Ignacio H. Escapa

    2008-12-01

    Full Text Available The plant and tetrapod fossil record of the Cañadón Asfalto Formation (Middle to Late Jurassic found in Cerro Cóndor area (Chubut Province is summarized here. The flora is dominated by conifers (Araucariaceae, Cupressaceae sensu lato but also includes ferns and equisetaleans. The tetrapod fauna is composed of dinosaur taxa described in the 70's as well as other remains recently described and other vertebrate groups such as amphibians, turtles, and mammals. The amphibian remains have been interpreted as representatives of a new species of Notobatrachus, considered one of the most basal members of the anuran lineage. Similarly, turtle remains have been recently recognized as a new species of basal turtle, bringing valuable information about the early evolution of this group. The dinosaur remains are largely dominated by saurischian taxa, represented by basal forms of Eusauropoda and Tetanurae. In addition, three different mammalian species have been identified and considered as early representatives of an endemic Gondwanan mammalian fauna. The fossil record of this formation represents the most completely known biota from the continental Middle to Late Jurassic of the Southern Hemisphere and one of the most complete of the entire world.Se resume brevemente el registro de plantas y tetrápodos fósiles de la Formación Cañadón Asfalto (Jurásico Medio a Superior en el área de Cerro Cóndor, provincia de Chubut. La flora está conformada por coníferas de las familias Araucariaceae y Cupressaceae sensu lato dominando la asociación, la cual se completa con helechos y equisetales en proporciones menores. La fauna de tetrápodos se compone por los clásicos dinosaurios descriptos en los 70`s, a los que se suman nuevos restos pertenecientes a este grupo, así como anfibios, tortugas y mamíferos coleccionados en la última década. Los restos de anfibios han sido interpretados como representantes de una nueva especie de Notobatrachus, considerado

  17. Glaciares de escombros fósiles en el cordón Leleque, Noroeste del Chubut: significado paleoclimático y paleográfico

    Directory of Open Access Journals (Sweden)

    Lucas Ruiz

    2012-09-01

    Full Text Available Este trabajo analiza la relación actual y pasada del ambiente periglacial y glaciario en los Andes de la Patagonia norte (41°- 43° L.S.. Es la primera vez que un estudio de estas características es llevado a cabo en esta región. A partir del análisis y caracterización de geoformas relacionadas con el permafrost de montaña y el ambiente glaciario, el análisis de las condiciones climáticas y el uso de análogos actuales, se presenta una reconstrucción paleogeográfica y paleoclimática del Cordón Leleque. El Cordón del Plata, en los Andes Centrales, con glaciares convencionales y glaciares de escombros, se utiliza como análogo actual de las condiciones pasadas en el Cordón Leleque. A partir de la ubicación espacial de las diferentes geoformas reconocidas en el Cordón Leleque se reconocieron cuatro grupos. Utilizando la relación entre la altura de la línea de equilibrio regional y la altura del límite de permafrost de montaña, se derivaron las variaciones climáticas necesarias que pudieron generar los diferentes grupos. Estos resultados son comparados con trabajos previos.

  18. Levaduras fermentadoras aisladas de Cyttaria hariotii (Fungi en bosques Andino-Patagónicos (Argentina Fermenting yeasts isolated from Cyttaria hariotii (Fungi in the Andean Patagonic Forest

    Directory of Open Access Journals (Sweden)

    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

  19. Extensive MIS 3 glaciation in southernmost Patagonia revealed by cosmogenic nuclide dating of outwash sediments

    Science.gov (United States)

    Darvill, Christopher M.; Bentley, Michael J.; Stokes, Chris R.; Hein, Andrew S.; Rodés, Ángel

    2015-11-01

    The timing and extent of former glacial advances can demonstrate leads and lags during periods of climatic change and their forcing, but this requires robust glacial chronologies. In parts of southernmost Patagonia, dating pre-global Last Glacial Maximum (gLGM) ice limits has proven difficult due to post-deposition processes affecting the build-up of cosmogenic nuclides in moraine boulders. Here we provide ages for the Río Cullen and San Sebastián glacial limits of the former Bahía Inútil-San Sebastián (BI-SSb) ice lobe on Tierra del Fuego (53-54°S), previously hypothesised to represent advances during Marine Isotope Stages (MIS) 12 and 10, respectively. Our approach uses cosmogenic 10Be and 26Al exposure dating, but targets glacial outwash associated with these limits and uses depth-profiles and surface cobble samples, thereby accounting for surface deflation and inheritance. The data reveal that the limits formed more recently than previously thought, giving ages of 45.6 ka (139.9/-14.3) for the Río Cullen, and 30.1 ka (+45.6/-23.1) for the San Sebastián limits. These dates indicate extensive glaciation in southern Patagonia during MIS 3, prior to the well-constrained, but much less extensive MIS 2 (gLGM) limit. This suggests the pattern of ice advances in the region was different to northern Patagonia, with the terrestrial limits relating to the last glacial cycle, rather than progressively less extensive glaciations over hundreds of thousands of years. However, the dates are consistent with MIS 3 glaciation elsewhere in the southern mid-latitudes, and the combination of cooler summers and warmer winters with increased precipitation, may have caused extensive glaciation prior to the gLGM.

  20. 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

  1. Audio-magnetotelluric survey to characterize the Sunnyside porphyry copper system in the Patagonia Mountains, Arizona

    Science.gov (United States)

    Sampson, Jay A.; Rodriguez, Brian D.

    2010-01-01

    The Sunnyside porphyry copper system is part of the concealed San Rafael Valley porphyry system located in the Patagonia Mountains of Arizona. The U.S. Geological Survey is conducting a series of multidisciplinary studies as part of the Assessment Techniques for Concealed Mineral Resources project. To help characterize the size, resistivity, and skin depth of the polarizable mineral deposit concealed beneath thick overburden, a regional east-west audio-magnetotelluric sounding profile was acquired. The purpose of this report is to release the audio-magnetotelluric sounding data collected along that east-west profile. No interpretation of the data is included.

  2. Rime Mushrooms - Extreme Rime Ice Buildup on Mountain Summits of Southern Patagonia

    Science.gov (United States)

    Whiteman, C. D.

    2015-12-01

    The Southern Patagonian Andes are known among mountain climbers for a meteorological phenomenon that occurs there but is unknown in many other mountain areas. The phenomenon is the buildup of rime ice in large bulbous or mushroom-shaped accretions on the windward side of projecting mountain summits, ridges and exposed near-vertical rock faces. These "ice mushrooms" have never been investigated scientifically. This talk will introduce the audience to ice mushrooms, describe where they are found, consider the meteorological factors leading to their formation, and illustrate how they are negotiated by mountain climbers using photographs and descriptions from Southern Patagonia.

  3. El cariotipo fundamental de Alstroemeria patagonica (Alstroemeriaceae) The fundamental karyotype of Alstroemeria patagonia (Alstroemeriaceae)

    OpenAIRE

    Carlos M Baeza; Gloria Rojas; Eduardo Ruiz

    2011-01-01

    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 % = ...

  4. 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

    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 ....../single grain fading rates. The third age is supported by an alternative geological interpretation, and the two ages consistent with the existing chronology imply that in the Strait of the Magellan the hills of the Brunswick peninsula (>70 m.a.s.l) were deglaciated at around 22 ka....

  5. 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

  6. Food habits of common barn-owls along an elevational gradient in Andean Argentine Patagonia

    OpenAIRE

    Travaini, Alejandro; Donázar, José A.; Ceballos, Olga; Rodríguez, Alejandro; Hiraldo, F.; Delibes, M.

    1997-01-01

    We evaluated the diet of Common Barn-owls (Tyto alba) along an elevational gradient in Argentine Patagonia. Small mammals (mainly rodents) were the main prey accounting for 93.2% of total prey items. Consumption of rodents appeared to be dependent on their availability. Sizes of mam­ malian prey were variable but most ranged from 10—100 g in body mass. We concluded that the diet of these barn owls could be used as an index of cricetid rodent populations along ...

  7. Ocupación urbana de espacios litorales: gestión del riesgo e iniciativas de manejo en una comunidad patagónica automotivada (Playa Magagna, Chubut, Argentina

    Directory of Open Access Journals (Sweden)

    Alejandro Monti

    2008-01-01

    Full Text Available Playa Magagna es un pequeño asentamiento urbano para recreación estival y de fin de semana, instalado en una típica planicie de acumulación marina de la costa patagónica, sujeta a fuerte influencia de la erosión marina y remoción en masa. Este artículo describe el modo en que los habitantes han procurado mitigar el efecto de ambas funciones forzantes sobre sus casas y otros bienes del entorno doméstico, y muestra que las respuestas individuales han tenido que ser progresivamente complementadas por acciones colectivas y gestiones intersectoriales, a medida que el uso local y regional del espacio fue creciendo. Nuestro trabajo reconstruye la historia socio ambiental a lo largo de 40-50 años, y la interpreta en términos de gestión del riesgo, y del manejo costero, mostrando que la vulnerabilidad física de los contextos expuestos al peligro fue reducida mediante medidas estructurales, y que la vulnerabilidad social, política e institucional fue disminuida incrementando la cohesión interna y el liderazgo. Esta secuencia de eventos es esperable únicamente bajo dos condiciones específicas: espacios habitables con limitada capacidad portante, y una comunidad local automotivada. De no existir una comunidad local con capacidad de autoajuste, deberán esperarse resultados muy diferentes, aun con similares restricciones del medio físico.

  8. Ocupación urbana de espacios litorales: gestión del riesgo e iniciativas de manejo en una comunidad patagónica automotivada (Playa Magagna, Chubut, Argentina)

    OpenAIRE

    Alejandro Monti; Anamaría Escofet

    2008-01-01

    Playa Magagna es un pequeño asentamiento urbano para recreación estival y de fin de semana, instalado en una típica planicie de acumulación marina de la costa patagónica, sujeta a fuerte influencia de la erosión marina y remoción en masa. Este artículo describe el modo en que los habitantes han procurado mitigar el efecto de ambas funciones forzantes sobre sus casas y otros bienes del entorno doméstico, y muestra que las respuestas individuales han tenido que ser progresivamente complementada...

  9. 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

  10. 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.

  11. en Argentina en los noventa

    Directory of Open Access Journals (Sweden)

    Marcelo Fabián Delfini

    2005-01-01

    Full Text Available Se analizan los efectos de la implantación de las políticas económicas neoliberales desde 1990 en Argentina sobre la distribución del ingreso y la pobreza, en un marco en que el crecimiento económico no provocó disminuciones sustantivas sobre las variables en estudio. Se emplea el concepto de “estancamiento dinámico ” para analizar las variables propuestas, pues éste sí permite dar cuenta de las regulaciones vigentes durante la década en estudio.

  12. Argentina en el sistema internacional

    OpenAIRE

    Tini, María Natalia

    2002-01-01

    El presente trabajo apunta a analizar cuál es el lugar "real" que ocupa la Argentina en el Sistema Internacional, en contraste, con el lugar "ideal" en que lo ha ido posicionando nuestra dirigencia en los últimos 10 años. Para ello, es esencial realizar un breve repaso de la política exterior llevada a cabo por las administraciones Menem y De La Rúa, como sustento empírico de dicho análisis. La hipótesis plantea que para proyectar una adecuada política exterior es necesario formular un ...

  13. Eastern Andean environmental and climate synthesis for the last 2000 years BP from terrestrial pollen and charcoal records of Patagonia

    Science.gov (United States)

    Sottile, G. D.; Echeverria, M. E.; Mancini, M. V.; Bianchi, M. M.; Marcos, M. A.; Bamonte, F. P.

    2015-06-01

    The Southern Hemisphere Westerly Winds (SWW) constitute an important zonal circulation system that dominates the dynamics of Southern Hemisphere mid-latitude climate. Little is known about climatic changes in the Southern South America in comparison to the Northern Hemisphere due to the low density of proxy records, and adequate chronology and sampling resolution to address environmental changes of the last 2000 years. Since 2009, new pollen and charcoal records from bog and lakes in northern and southern Patagonia at the east side of the Andes have been published with an adequate calibration of pollen assemblages related to modern vegetation and ecological behaviour. In this work we improve the chronological control of some eastern Andean previously published sequences and integrate pollen and charcoal dataset available east of the Andes to interpret possible environmental and SWW variability at centennial time scales. Through the analysis of modern and past hydric balance dynamics we compare these scenarios with other western Andean SWW sensitive proxy records for the last 2000 years. Due to the distinct precipitation regimes that exist between Northern (40-45° S) and Southern Patagonia (48-52° S) pollen sites locations, shifts on latitudinal and strength of the SWW results in large changes on hydric availability on forest and steppe communities. Therefore, we can interpret fossil pollen dataset as changes on paleohydric balance at every single site by the construction of paleohydric indices and comparison to charcoal records during the last 2000 cal yrs BP. Our composite pollen-based Northern and Southern Patagonia indices can be interpreted as changes in latitudinal variation and intensity of the SWW respectively. Dataset integration suggest poleward SWW between 2000 and 750 cal yrs BP and northward-weaker SWW during the Little Ice Age (750-200 cal yrs BP). These SWW variations are synchronous to Patagonian fire activity major shifts. We found an in phase

  14. 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. PMID:25041507

  15. Flavonols, alkaloids, and antioxidant capacity of edible wild berberis species from patagonia.

    Science.gov (United States)

    Ruiz, Antonieta; Zapata, Moises; Sabando, Constanza; Bustamante, Luis; von Baer, Dietrich; Vergara, Carola; Mardones, Claudia

    2014-12-24

    There are 20 species of the Berberidaceae family described in Chile, whose fruits are edible and show high anthocyanin and hydroxycinnamic acid levels. Berberis microphylla G. Forst, commonly known as calafate, is the most extensively distributed. Flavonols and alkaloids in seed, pulp, skin, and whole calafate berry extracts and other Berberis were studied using HPLC-DAD-ESI-MS/MS and HPLC with fluorescence detector. Berry samples from different locations in Chilean Patagonia, including different phenological stages, were systematically addressed. Results were compared with other organs of the plant and with other Berberis species. Total flavonol concentration in calafate (n = 65) was 1.33 ± 0.54 μmol/g. Glycosyl metabolites of quercetin and isorhamnetin were the most abundant. Similar profiles were observed in calafate from distinct locations, but important differences were observed for the other edible Berberis species. Calafate pulp and skin have higher flavonol concentrations than seeds, and the maturation process reduced its levels. TEACCUPRAC and TEACABTS of whole calafate extracts and fractions are also explored. Finally, only berberine was detected in the fruit (0.001%), mainly in seeds. Results contribute to the promotion of this berry as a superfruit from Patagonia. PMID:25495577

  16. Last glacial maximum environments in northwestern Patagonia revealed by fossil small mammals

    Science.gov (United States)

    Tammone, Mauro N.; Hajduk, Adan; Arias, Pablo; Teta, Pablo; Lacey, Eileen A.; Pardiñas, Ulyses F. J.

    2014-07-01

    Comparisons of historical and modern assemblages of mammals can yield important insights into patterns and processes of environmental change. Here, we present the first analyses of small mammal assemblages present in northern Patagonia during the last glacial maximum (LGM). Using remains obtained from owl pellets excavated from an archeological cave site (Arroyo Corral I, levels VII-V, carbon dates of 22,400-21,530 cal yr BP), we generate estimates of the minimum number of individuals for all species detected; these estimates, in turn are used to determine relative species abundances. Comparisons of these data with similar analyses of small mammal remains obtained from a second archeological site (ACoII, levels IV-V, carbon dates of 10,010-9220 cal yr BP) as well as from modern owl pellets reveal pronounced changes in relative species abundance since the LGM. In particular, Euneomys chinchilloides and Ctenomys sociabilis - the predominant species during the LGM - declined markedly, suggesting a change from open, bare habitat punctuated by patches of wet meadows and shrubs to the more densely vegetated mosaic of ecotone habitats found in this region today. These data provide important new insights into the environmental changes that have occurred in northern Patagonia over the last 20,000 years.

  17. [The health system of Argentina].

    Science.gov (United States)

    Belló, Mariana; Becerril-Montekio, Victor M

    2011-01-01

    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 contributions of employers and employees. Finally, the private sector includes all those private providers offering services to individuals, OS beneficiaries and all those with private health insurance.This sector also includes private insurance agencies called Prepaid Medicine Enterprises, financed mostly through premiums paid by families and/or employers.This paper also discusses some of the recent innovations implemented in Argentina, including the program Remediar.

  18. [The health system of Argentina].

    Science.gov (United States)

    Belló, Mariana; Becerril-Montekio, Victor M

    2011-01-01

    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 contributions of employers and employees. Finally, the private sector includes all those private providers offering services to individuals, OS beneficiaries and all those with private health insurance.This sector also includes private insurance agencies called Prepaid Medicine Enterprises, financed mostly through premiums paid by families and/or employers.This paper also discusses some of the recent innovations implemented in Argentina, including the program Remediar. PMID:21877098

  19. Confederações indígenas em luta por participação política, comercial e territorial: Argentina, 1852 - 1859 Argentinean native-american confederations in action: politics, commerce and territories (1852-1859

    Directory of Open Access Journals (Sweden)

    Gabriel Passetti

    2009-01-01

    Full Text Available Entre 1852 e 1859, a atual Argentina se encontrava politicamente dividida entre Buenos Aires e a Confederação, que congregava as demais Províncias. Nesse período, diferentes grupos étnicos dos pampas, dos Andes e da Patagônia se organizaram em confederações indígenas com o objetivo de enfrentar os avanços territoriais, defender suas autonomias e a participação em lucrativas redes de comércio. Nesta luta por autonomia política, territorial e comercial, negociaram com os grupos criollos em luta pelo poder, avaliaram seus projetos e aderiram a aquele que os reconheceu enquanto interlocutores políticos e aliados militares. Participantes ativos da política argentina, conseguiram reconquistar territórios e oferecer intensas resistências aos criollos.Argentina was divided, between 1852 and 1859 in two political groups: the Province of Buenos Aires and the Argentine Confederation. Strong native-american confederations from the pampas, the Andes and Patagonia, arose interested in political autonomy, deffence of territories and commerce. They dealed with the criollos, evaluated their project for the nation and joined those who recognized them as political and military allies. Active members of the Argentinean politics in that time, they re-conquered lands and offered intense resistances to the criollos.

  20. 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

  1. 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

  2. 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

  3. 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

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    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

  4. 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.

  5. Combined impact of ultraviolet radiation and increased nutrients supply: A test of the potential anthropogenic impacts on the benthic amphipod Amphitoe valida from Patagonian waters (Argentina

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    Macarena S. Valiñas

    2014-08-01

    Full Text Available Experiments were conducted during the Austral Summer of 2014 to determine the effects of increased nutrient input and ultraviolet radiation (UVR on the food consumption rate (FCR and food preference in the amphipod Amphitoe valida. We collected specimens from the Patagonian coast (Argentina, from beaches close (Barrancas Blancas; BB and further away (Cangrejales; C from the Chubut River, which constitutes the potential source of eutrophication. Organisms were exposed to different radiation regimes (full radiation vs. PAR only and fed with different macroalgae diets (i.e., from different geographical location and with different quality in terms on nutrient content. Males collected from C showed food compensation, consuming more food under low-nutrient diets, while no compensation was observed in males from BB. Regardless of their origin, UVR decreased the FCR when males where fed on ambient nutrient diets, but not when males fed on high-quality diets indicating that in the former case, individuals were in worse physiological conditions to cope with UVR; food quality, however, significantly counteracted the deleterious effects of UVR on FCR. Females collected from the two beaches showed similar FCR under high-nutrient diet and had no food compensation when fed in low-nutrient diets. Females were more vulnerable to UVR, since their FCR were lower when exposed to UV radiation independent of the diet. Our results show that under anthropogenic eutrophication and high solar UVR levels an increase in the nutrient input could favor only males of A. valida, by reducing the negative effects of UVR on their FCR. Nevertheless, these nutrient inputs might cause additional problems like anoxia, as a result of an unusual macroalgal growth, thus affecting amphipod’s survival.

  6. Argentina: toward energy self-sufficiency

    International Nuclear Information System (INIS)

    Argentina has one operating nuclear power plant, the 367 MWe Atucha I supplied by Kraftwerk Union. The second plant, at Rio Tercero, is a standard 600 MWe CANDU, expected to be in service in 1981. Contractors are Atomic Energy of Canada Ltd. for the nuclear steam supply, and Italimpianti for the balance of the plant. Bids are being considered for a third plant, Atucha II. Argentina is moving gradually towards developing a nuclear industry based on its own uranium and manpower resources. (LL)

  7. Argentina en el MERCOSUR (2007-2011)

    OpenAIRE

    Gentile, María Elisa

    2012-01-01

    En este trabajo se analizan los principales aportes de Argentina en el MERCOSUR, bajo el primer gobierno de Cristina Fernández de Kirchner teniendo en cuenta que el gobierno de la Argentina hizo del bloque regional uno de los ejes principales de su política exterior. Como resultado, en los últimos años han aparecido indicadores de resurgimiento del MERCOSUR, a pesar de lo cual aún persisten algunos conflictos.

  8. La materia orgánica particulada: comparación de métodos para su determinación y su valor como indicador de calidad de suelos del Chubut Particulate organic-matter: a comparison of methods for its determination and its role as an indicator of soil quality for some soils in the province of Chubut

    Directory of Open Access Journals (Sweden)

    Lina Sonia Videla

    2008-12-01

    Full Text Available La materia orgánica particulada (MOP es un componente dinámico del suelo, que responde selectiva y rápidamente a los cambios de manejo y distintos tipos de disturbios. El objetivo de este estudio fue comparar dos técnicas de determinación de MOP en distintos suelos y evaluar el potencial de esta variable como indicadora de calidad de los mismos. Se estudiaron tres sitios ecológicos de la provincia del Chubut con distinto manejo o afectados por distintos disturbios: Media Luna Clausura (ML C, Media Luna Pastoreo (ML P, Puerto Madryn bioperturbado (PM B, Puerto Madryn no bioperturbado (PM NB, Punta Ninfas no erosionado (PN NE y Punta Ninfas erosionado (PN E. En muestras de suelos extraídas de 0 a 5 cm (PM y PN y de 0 a 10 cm (ML de profundidad se determinó la materia orgánica total (MOT y la MOP por vía húmeda (MOPh (Método Walkley y Black y por ignición en mufla (MOPi a 430 °C. En los Molisoles de ML y en los Aridisoles de PM la MOPi fue mayor que la MOPh, mientras que para los Aridisoles de PN no se registraron diferencias significativas entre los dos métodos. Para los suelos con carbonatos (PM o con alofanos (ML, el método por ignición sobreestimó los contenidos de MOP. La MOT presentó una alta correlación con la MOPh y con la MOPi para todos los suelos en conjunto (r² = 0,89 y r² = 0,73, respectivamente. El suelo que presentó una mayor relación MOP/MOT fue PN NE. En contraste, el suelo PN E, mostró los valores más bajos para esta relación, lo que indicaría, por un lado, que la poca MO que contienen estos suelos está predominantemente asociada a la fracciónParticulate organic-matter (MOP is a dynamic soil component that quickly and selectively responds to management changes and to different disturbance regimes. We compared two techniques to determine the MOP content in different soils and assessed the potential of this variable as an indicator of soil quality. We studied the soils of three ecological sites located

  9. XI Simposio de Investigación en Enseñanza de la Física : 26 al 28 de octubre de 2012. Esquel (Chubut)

    OpenAIRE

    Cordero, Silvina

    2012-01-01

    La “enseñanza de la Física”, como área de conocimientos, conjuga aportes de diversas disciplinas para el análisis de los procesos de (re)construcción de conocimientos físicos en espacios educativos. Es un campo de investigación específico, considerado en Argentina una “didáctica específica”, y por eso frecuentemente sólo denominado Didáctica de la Física. Su historia ha estado muy impregnada de una visión psicologista de los fenómenos educativos. También es un campo muy complejo, por ser u...

  10. Poverty and Health in Argentina

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    Maria Alejandra Silva

    2009-06-01

    Full Text Available This article examines health conditions in the rural areas of Central Argentina, the country’s main region for soy-bean production and export. Health conditions are analyzed through the concepts of emerging and re-emerging diseases in a context of increasing poverty. Data on poverty and health was obtained from both primary sources (trade union, government officials, rural doctors and the South Watch/FA/FODEPAL/UNR working group and secondary sources (IPEC/INDEC, IDESA, Consultora Equis, the Argentine Ministry of Employment, ILO, the Ministry of Health, the Ministry of the Environment, toxicology centers and rural doctors. Analysis of rural health conditions gives cause for concern. There is evidence of deterioration in the social determinants of health such as an increase in rural and urban poverty associated with informal employment and child labor. At the same time lack of government epidemiological and toxicological data appears to hide or distort the reality of health conditions.

  11. Soybean biomass produced in Argentina

    DEFF Research Database (Denmark)

    Semino, Stella; Paul, Helena; Tomei, Julia;

    Soybean biomass for biodiesel, produced in Argentina amongst other places, is considered by some to reduce greenhouse gas emissions and mitigate climate change when compared with fossil fuel. To ensure that the production of biofuels is ‘sustainable', EU institutions and national governments are...... been demonstrated in several studies, but the atmospheric impact of soybean cultivation has not been tested in situ. Some of the models for climate impact (N2O emissions etc) are based on in vitro studies, while field data are scarce. The situation, which is outside the control of the EU, has not been...... environmental sustainability. This is exemplified by soy, whose cultivation undermines the climate benefit claimed for soy-based biodiesel. This paper concludes that to certify soy monocultures as sustainable would exacerbate existing climatic and environmental problems....

  12. Mecanismos de tribalización en la patagonia: desde la gran crisis al primer gobierno peronista.

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    Walter Delrio

    2005-12-01

    Full Text Available En 1937 el gobierno argentino decide desalojar y trasladar a la tribu Nahuelpán bajo acusaciones de extranjería e in-civilización. Luego de seis años, la medida es revisada y se inicia un proceso de restitución parcial de las tierras involucradas seleccionándose desde el estado a quienes se continuaría reconociendo como "tribu" Nahuelpán. A partir de este caso enmarcado en el contexto de las relaciones establecidas por las comunidades indígenas del territorio nacional de Chubut con las autoridades nacionales y las redes locales de poder, se propone un análisis del proceso de construcción del espacio social para los pueblos originarios en la matriz estado-nación-territorio en el período que va de la gran crisis del '30 al primer gobierno peronista. Se abordan en particular los mecanismos de tribalización en la interfase entre políticas oficiales y agencia aborigen.In 1937, the Argentine government decided to displace and remove the Nahuelpán tribe accused of foreign and uncivilized behavior. Six years later this measure was reviewed starting a process of partial land restitution in which the state selected who will continue to be considered as member of the above mentioned tribe. Focusing in that case, framed by the relationship established between indigenous communities of the national territory of Chubut and state authorities or local nets of power, this article analyzes the process leading to the construction of a social space in the state-nation-territory matrix since the 1930' great crisis until the first period of President Juan Perón.

  13. Paleoenvironmental reconstruction of the coastal Monte Léon and Santa Cruz formations (Early Miocene) at Rincón del Buque, Southern Patagonia: A revisited locality

    Science.gov (United States)

    Raigemborn, M. Sol; Matheos, Sergio D.; Krapovickas, Verónica; Vizcaíno, Sergio F.; Bargo, M. Susana; Kay, Richard F.; Fernicola, Juan C.; Zapata, Luciano

    2015-07-01

    Sedimentological, ichnological and paleontological analyses of the Early Miocene uppermost Monte León Formation and the lower part of the Santa Cruz Formation were carried out in Rincón del Buque (RDB), a fossiliferous locality north of Río Coyle in Santa Cruz Province, Patagonia, Argentina. This locality is of special importance because it contains the basal contact between the Monte Léon (MLF) and the Santa Cruz (SCF) formations and because it preserves a rich fossil assemblage of marine invertebrates and marine trace fossils, and terrestrial vertebrates and plants, which has not been extensively studied. A ˜90 m-thick section of the MLF and the SCF that crops out at RDB was selected for this study. Eleven facies associations (FA) are described, which are, from base to top: subtidal-intertidal deposits with Crassotrea orbignyi and bioturbation of the Skolithos-Cruziana ichnofacies (FA1); tidal creek deposits with terrestrial fossil mammals and Ophiomorpha isp. burrows (FA2); tidal flat deposits with Glossifungites ichnofacies (FA3); deposits of tidal channels (FA4) and tidal sand flats (FA5) both with and impoverish Skolithos ichnofacies associated; marsh deposits (FA6); tidal point bar deposits recording a depauperate mixture of both the Skolithos and Cruziana ichnofacies (FA7); fluvial channel deposits (FA8); fluvial point bar deposits (FA9); floodplain deposits (FA10); and pyroclastic and volcaniclastic deposits of the floodplain where terrestrial fossil mammal remains occur (FA11). The transition of the MLF-SCF at RDB reflects a changing depositional environment from the outer part of an estuary (FA1) through the central (FA2-6) to inner part of a tide-dominated estuary (FA7). Finally a fluvial system occurs with single channels of relatively low energy and low sinuosity enclosed by a broad, low-energy floodplain dominated by partially edaphized ash-fall, sheet-flood, and overbank deposits (FA8-11). Pyroclastic and volcaniclastic materials throughout the

  14. Preliminary K/Ar geochronology of the Crater Basalt volcanic field (CBVF, northern Patagonia

    Directory of Open Access Journals (Sweden)

    Z. Pécskay

    2007-03-01

    Full Text Available The Crater Basalt volcanic field is one of the Quaternary intraplate basaltic fields in northern Patagonia. A systematic geological, volcanological and geochronological study of CBVF indicates a multistage history of eruptions of basaltic volcanoes. K/Ar dating, using whole rock samples shows that the measured analytical ages are fully consistent with the available stratigraphic control. The radiometric ages fall into three distinct, internally consistent age groups, which give evidence that there were at least three major episodes of volcanic activity, at about 1.0 Ma, 0.6 Ma and 0.3 Ma ago. The age differences appear to be just significant, even although less than 10 % radiogenic argon was found in the isotope analysis of whole rock samples.

  15. 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.

  16. Linajes mitocondriales fundadores en restos humanos prehistóricos de Patagonia y Tierra del Fuego

    OpenAIRE

    Moraga, Mauricio; Barrientos, Gustavo; Mena, Francisco; Reyes, Omar; Goñi, Rafael; Franco, N.; Borrero, Luis Alberto

    2009-01-01

    El registro arqueológico de Patagonia cuenta con la evidencia más antigua de ocupación humana en América (Monte Verde, aprox.14.500 cal. AP), con un gran número de sitios del Holoceno, algunos de los cuales contienen huesos humanos tan antiguos como 8.800 años cal. AP (Baño Nuevo 1). ADN mitocondrial antiguo fue recuperado exitosamente desde más de 30 muestras óseas de un total superior a los 40 individuos. Las muestras corresponden a sitios de ambos lados de la cordillera entre los 45º y 54º...

  17. 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.

  18. Lack of founding Amerindian mitochondrial DNA lineages in extinct aborigines from Tierra del Fuego-Patagonia.

    Science.gov (United States)

    Lalueza, C; Pérez-Pérez, A; Prats, E; Cornudella, L; Turbón, D

    1997-01-01

    Ancient DNA from bones and teeth of 60 individuals from four extinct human populations from Tierra del Fuego-Patagonia (Selknam, Yamana, Kaweskar and Aonikenk) has been extracted and the mitochondrial DNA (mtDNA) amplified by using the polymerase chain reaction. High-resolution analysis of endonuclease restriction site variation in the mtDNA and sequencing of its hypervariable non-coding control region, revealed complete absence of two of the four primary mitochondrial haplotype groups present in contemporary Amerinds, namely A and B. In contrast, haplogroups C and D were found in all but one sample with frequencies of approximately 38% and 60%. These results, together with the decreasing incidence of group A in more southerly latitudes in the American continent and the absence of cluster B above 55 degrees North in America and Asia, argue that the first settlers entering America 21000-14000 years ago already lacked both mtDNA lineages.

  19. Edematogenic and myotoxic activities of the Duvernoy's gland secretion of Philodryas olfersii from the north-east region of Argentina.

    Science.gov (United States)

    Acosta de Pérez, Ofelia; Leiva de Vila, Laura; Peichoto, María Elisa; Maruñak, Silvana; Ruíz, Raquel; Teibler, Pamela; Gay, Carolina; Rey, Laura

    2003-12-01

    Philodryas olfersii is found in South America, from Amazonas to Patagonia. It is important to characterize the venom of P. olfersii, who inhabits the North-East region of Argentina, since snake venoms are known to exhibit considerable variability in composition and biological activities. In this work, mice weighing 18-20 g (n = 4 for each experimental group) were used. For the edematogenic activity mice were injected s.c. in the right foot pad with 50 microl of solutions containing different amounts of venom, whereas the left foot pad was injected with 50 microl of PBS. Two hours after injection mice were killed by cervical dislocation and both feet were cut off and weighed individually. For the myotoxic activity mice were injected i.m. with 100 microl of solutions containing 40 microg of venom. Blood samples were extracted after 1, 3, 6, 8, 10, 12, 14, 16 and 24 h of venom injection to determinate serum CPK activity and mice were sacrificed at the same time intervals to obtain the inoculated gastrocnemius muscle. They were fixed with Bouin solution and stained with Hematoxylin-Eosin. Results showed that P. olfersii venom exhibits a high edematogenic activity (MED = 0.31 microg) and a moderate myotoxic activity. Myonecrosis reached its highest level after 12 h of venom injection as shown by plasmatic CPK levels (5,401 +/- 330 IU/l) and microscopic assay. It demonstrates the potential toxicity of the venom of P. olfersii, who inhabits the North-East region of Argentina. It also reinforces the original warning concerning the potential danger of bites by colubrids. PMID:15002753

  20. Fire affects size and shape of Fabiana imbricata Shurblands in northwestern Patagonia

    Science.gov (United States)

    Oddi, Facundo; Ghermandi, Luciana

    2010-05-01

    Fire is a major environmental ecological agent acting in the landscape configuration and a factor that models vegetation in Mediterranean environments. Fire impacts differently in the landscape due to the intrinsic heterogeneity of the environments and the characteristics associated with each fire event. After fire, density of patches may be increased and the size of them may be reduced because fire generates areas of different successional stages. Landscape ecology seems to be the ideal theoretical approach to study the fire impact in fire prone environments. Landscape ecology has been greatly favoured by a significant progress in the last years of geographic information technologies (GIT) (remote sensing, GIS, GPS). The study area of this work is the San Ramon ranch (22,000 ha) located in Northwester Patagonia in the ecotone between the sub Antarctic forest in the West and the Patagonian steppe in the East. We studied sectors of the ranch with different fire recurrence in the last 40 years and we mapped Fabiana imbricata shrubland with GPS. This specie is a native shrub characteristic of Northwester Patagonia grasslands and its dynamic is not very known. Shrublands compete for the space with palatable grasses that are used for forage and livestock production, the main economic resource of the region. We analysed the mapped patches with GIS software, and we assessed landscape metrics to determine differences between sites with different fire recurrence. In the future we foresee the integrated use of satellite imagery with different resolution to add to GIS other important spatial variables (topography, hydrography, aspect, soil) to develop models that can explain landscape metrics, spatial configuration and the potential shrub invasion in the grassland.

  1. Preliminary K/Ar geochronology of the Crater Basalt volcanic field (CBVF, northern Patagonia

    Directory of Open Access Journals (Sweden)

    Z. Pécskay

    2007-11-01

    Full Text Available The Crater Basalt volcanic field is one of the Quaternary intraplate basaltic fields in northern Patagonia. A systematic geological, volcanological and geochronological study of CBVF indicates a multistage history of eruptions of basaltic volcanoes. K/Ar dating, using whole rock samples shows that the measured analytical ages are fully consistent with the available stratigraphic control. The radiometric ages fall into three distinct, internally consistent age groups, which give evidence that there were at least three major episodes of volcanic activity, at about 1.0 Ma, 0.6 Ma and 0.3 Ma ago. The age differences appear to be just significant, even although less than 10 % radiogenic argon was found in the isotope analysis of whole rock samples.El campo volcánico del Basalto Cráter (CVBC constituye uno de los campos basálticos cuaternarios de intraplaca de la Patagonia septentrional. El estudio sistemático de la geología, volcanología y geocronología del CVBC muestra una historia eruptiva multiepisódica de volcanes basálticos. Las dataciones K-Ar realizadas sobre roca total son coherentes con el control estratigráfico. Las edades obtenidas para el Basalto Cráter permiten distinguir tres episodios diferentes, pero individualmente coherentes, de actividad volcánica, ocurridos hace ~1,0 Ma; 0,6 Ma y 0,3 Ma. Las diferencias de edad parecen ser significativas, aún cuando el contenido de argón radiogénico determinado en los análisis de roca total resultó menor al 10 %.

  2. Historical records of mercury in southern latitudes over 1600 years: Lake Futalaufquen, Northern Patagonia.

    Science.gov (United States)

    Daga, Romina; Ribeiro Guevara, Sergio; Pavlin, Majda; Rizzo, Andrea; Lojen, Sonja; Vreča, Polona; Horvat, Milena; Arribére, María

    2016-05-15

    Mercury is released to the environment from natural and anthropogenic sources, and through atmospheric transport is distributed globally. Lake Futalaufquen (42.8°S) is an oligotrophic lake located in Los Alerces National Park (Northern Patagonia), providing a remote and unpolluted study system. A lacustrine sedimentary sequence revealed 1600 years of Hg deposition, identifying natural baselines and marked peaks not correlated with long-range atmospheric transport. Organic matter and catchment erosion were discarded as Hg drivers. Natural background, pre-1300 CE Hg concentrations, ranged between 27 and 47 ng g(-1) (accumulation rates from 8 to 15μg m(-2) y(-1)). From 1300 CE on, the Hg background profile did not follow the generally increasing Hg pattern observed in both Southern and Northern Hemisphere since pre-industrial times. It was not until the last century that a 1.6-fold increase is observed in the Hg accumulation rate, considered among the lowest increments in southern South America. Noteworthy local/regional sources of Hg for this area, along with global transport, are forest fires and volcanic activity. Between approx. 1340 and 1510 CE, sharp increase in Hg concentration and accumulation rate (up to 204 ng g(-1) and 51 μg m(-2) y(-1), respectively) were clearly associated with extended fire episodes. Furthermore, high Hg peaks during the last 300 years were associated with volcanic eruptions in northernmost Patagonia together with fairly irregular fire episodes, caused by anthropogenic burning by settling population in the Andes. PMID:26938317

  3. Patrones biogeográficos de los tenebriónidos epigeos (Coleoptera: Tenebrionidae del Área Natural Protegida Península Valdés, Argentina: implicaciones para su conservación Biogeographic patterns of epigean tenebrionids (Coleoptera: Tenebrionidae from Protected Natural Area Península Valdés, Argentina: implications for its conservation

    Directory of Open Access Journals (Sweden)

    Rodolfo Carrara

    2011-12-01

    Full Text Available Se realizó un estudio sobre los patrones biogeográficos de los tenebriónidos epigeos (Coleoptera: Tenebrionidae que habitan el Área Natural Protegida Península Valdés (Chubut, Argentina, basado en datos de colecciones y material recolectado en viajes a la zona. Se presenta una lista exhaustiva de las especies en la que se consigna el grado de adaptación a la aridez de cada una de ellas; un análisis de la calidad del inventario y la estimación de la riqueza total de especies; una evaluación de los patrones de distribución y riqueza, y la identificación de áreas de significativa mayor riqueza o hotspots. Los resultados indicaron que 25 especies con diferente grado de adaptación a la aridez habitan la península, aunque se estima que la riqueza total del área debería ser de 27. Además, se reconoció que los rangos de distribución de los tenebriónidos siguen una distribución log-normal y que sólo 3 especies son endémicas. Espacialmente, la riqueza se distribuyó de forma agregada en la península y se determinaron 10 hotspots. Finalmente, considerando que en la península Valdés están permitidas actividades productivas que originan una importante degradación del hábitat, se examina la implicancia de los resultados para la conservación de los tenebriónidos epigeos.We conducted a study of the biogeographic patterns of epigean tenebrionids (Coleoptera: Tenebrionidae that inhabit the Protected Natural Area Península Valdés (Chubut, Argentina, based on data obtained from collections and collecting trips. We present a comprehensive species list, where we detail the degree of adaptation to aridity shown by each species, an analysis of the quality of the inventory, an estimation of total species richness, and an evaluation of distribution and richness patterns, with the identification of areas of significantly greater richness or "hotspots". The results indicated that 25 species with different degrees of adaptation to aridity

  4. Control of nuclear materials and materials in Argentina

    International Nuclear Information System (INIS)

    A general view about the safeguards activities in Argentina is presented. The national system of accounting for and control of nuclear materials is described. The safeguards agreement signed by Argentina are presented. (E.G.)

  5. 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.

  6. 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. PMID:25148565

  7. Day and night feeding habitat of Red Knots in Patagonia : Profitability versus safety?

    NARCIS (Netherlands)

    Sitters, HP; Gonzalez, PM; Piersma, T; Baker, AJ; Price, DJ; Sitters, Humphrey P.; González, Patricia M.; Baker, Allan J.; Price, David J.

    2001-01-01

    By radio-tracking and recording the movements of flocks. the distribution of feeding Red Knots (Calidris canutus rufa) was studied day and night at a migration stopover site near San Antonio Oeste, Rio Negro, Argentina in March and April 1998. By day, the birds fed in dense flocks of 500-4000 on an

  8. Discourse Coalitions in the Controversy around the HydroAysen Project in the Patagonia Region of Chile

    OpenAIRE

    Mar¨ªa Eugenia Merino; Mar¨ªa Elena Bello

    2014-01-01

    This paper explores the discourse coalitions that became evident during the conflict around the HydroAysen hydroelectric megaproject in the Patagonia region of Chile. We explore three nodal concepts around which the coalitions were constructed and the argumentative and rhetoric strategies used. The analysis, inspired by a socio constructivist approach and based on Hajer¡¯s argumentative method (2005), studies 40 discourse allocutions from relevant leaders and social actors publically availabl...

  9. Invasive salmonids and lake order interact in the decline of puye grande Galaxias platei in western Patagonia lakes.

    Science.gov (United States)

    Correa, Cristian; Hendry, Andrew P

    2012-04-01

    Salmonid fishes, native to the northern hemisphere, have become naturalized in many austral countries and appear linked to the decline of native fishes, particularly galaxiids. However, a lack of baseline information and the potential for confounding anthropogenic stressors have led to uncertainty regarding the association between salmonid invasions and galaxiid declines, especially in lakes, as these have been much less studied than streams. We surveyed 25 lakes in the Aysén region of Chilean Patagonia, including both uninvaded and salmonid-invaded lakes. Abundance indices (AI) of Galaxias platei and salmonids (Salmo trutta and Oncorhynchus mykiss) were calculated using capture-per-unit-effort data from gillnets, minnow traps, and electrofishing. We also measured additional environmental variables, including deforestation, lake morphometrics, altitude, and hydrological position (i.e., lake order). An information-theoretic approach to explaining the AI of G. platei revealed that by far the strongest effect was a negative association with the AI of salmonids. Lake order was also important, and using structural equation modeling, we show that this is an indirect effect naturally constraining the salmonid invasion success in Patagonia. Supporting this conclusion, an analysis of an independent data set from 106 mountain lakes in western Canada showed that introduced salmonids are indeed less successful in low-order lakes. Reproductive failure due to insufficient spawning habitat and harsh environmental conditions could be the cause of these limits to salmonid success. The existence of this effect in Chilean Patagonia suggests that low-order lakes are likely to provide natural ecological refugia for G. platei. Finally, pristine, high-order lakes should be actively protected as these have become rare and irreplaceable unspoiled references of the most diverse, natural lake ecosystems in Patagonia. PMID:22645814

  10. 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

  11. Fossil forests in the Austral Basin (Argentina) marking a Cenomanian heterogeneous forced regressive surface.

    Science.gov (United States)

    Varela, A N; Iglesias, A; Poiré, D; Zamuner, A; Richiano, S; Brea, M

    2016-05-01

    The mid-Cretaceous greenhouse period in the southern Patagonia Argentina (Austral Basin) is represented by the Mata Amarilla Formation. It is composed of three informal sections which were deposited in littoral and continental environments. The boundary between the lower and middle sections of the Mata Amarilla Formation shows a drastic reduction in accommodation/sediment supply (A/S) ratio, interpreted as a forced regressive surface. This surface is characterized by a well-developed palaeosol, associated with the extensive preservation of a podocarp-dominated fossil forest over a vast area (more than 5400 km(2) ). Sedimentological and palaeopedological analyses, in conjunction with forest structure, tree density and growth ring analyses, indicate that the mid-Cenomanian forced regression can be distinguished as a non-uniform surface developed over a short period of time. This sequence boundary is recognized through a heterogeneous regional surface, delimited in the western part of the study area by an erosional surface generated by a large lateral channel migration recorded by sheet-like channel deposits with transported logs. By comparison, towards the eastern part of the study area, it appears as a paraconformity bounded by a very mature vertic Alfisol, which may have taken 40-100 ky to develop, and the preservation of a fossil forest in life position with a minimum age of 337 years. It is concluded that the extensive presence of these fossil forests at the same stratigraphic level in a vast region respond to changes in A/S ratio in a forced regressive surface at basin scale. PMID:26663258

  12. 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

    2016-01-01

    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. PMID:27617993

  13. 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.

  14. Psychiatry and humanism in Argentina.

    Science.gov (United States)

    Niño Amieva, Alejandra

    2016-04-01

    The authors of the present selection of Latin American Psychiatry texts were characterized by a common deep humanistic attitude. These prolific writers were able to establish or extend the scope of the discipline in which they chose to act, questioning the establishment of rigid boundaries within the framework of a rigorous epistemological reflection. Thus the systematizing spirit of Jose Ingenieros' in the context of positivist evolutionism, resulted in the act of founding a discipline that integrated the biological and the social. In the case of Guillermo Vidal his conception of mental health went beyond the biomedical to consider psychotherapies as an emotional commitment, continence and empathic understanding; with regard to César Cabral his formation and extensive clinical practice resulted in a work defined by the inquiring into the theoretical concepts underlying Psychiatry and Clinical Psychology. This brief selection does not exhaust the issues or the level of ideas and discussions of Psychiatry in Argentina, but constitutes a textual corpus representative of a disciplinary conception understood as scientific and humanistic endeavor.

  15. 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. PMID:19017262

  16. Crustal structure across the Colorado Basin, offshore Argentina

    Science.gov (United States)

    Franke, Dieter; Neben, Soenke; Schreckenberger, Bernd; Schulze, Albrecht; Stiller, Manfred; Krawczyk, Charlotte M.

    2006-06-01

    The geology of the wide shelves surrounding the South Atlantic is closely linked to the kinematics and history of the opening of the ocean. However, several wide sedimentary basins, which developed along the margins show peculiarities that are not yet understood in the context of the evolution of the South Atlantic. The Colorado Basin, a wide sedimentary basin on the broad shelf of Argentina, extends in EW direction. The basin's evolution oblique or orthogonal to the continent-ocean boundary indicates that it is not a product of simple progressive extension and crustal thinning. In addition a basement high, paralleling the continental margin and separating the Colorado Basin from the deep-sea basin is a common interpretation. These findings are hardly in accordance with the idea that the Colorado Basin is an extensional basin that developed in conjunction with the early E-W opening phase of the South Atlantic in the Late Jurassic/Early Cretaceous. The composition, type, and structure of the basement, key points for the evaluation of the basins evolution, are widely speculative. In this context multichannel seismic reflection data from the Argentine Shelf and a 665-km-long onshore-offshore refraction profile, running across the Colorado Basin onto the coast are discussed in combination with gravity data. The stratigraphy for the sedimentary successions was adopted from the literature and the reflection seismic marker horizons formed besides the interval velocities the input for the starting model for refraction seismic traveltime modelling. The modelling strategy was an iterative procedure between refraction seismic traveltime and gravity modelling. The preparation of the density models was coarsely orientated on published velocity-density relations. The modelling results are in favour of a continuation of the main onshore geological features beneath the sedimentary infill of the Colorado Basin. We interpret the basement along the line from west to east as offshore

  17. Noble gas composition of subcontinental lithospheric mantle: An extensively degassed reservoir beneath Southern Patagonia

    Science.gov (United States)

    Jalowitzki, Tiago; Sumino, Hirochika; Conceição, Rommulo V.; Orihashi, Yuji; Nagao, Keisuke; Bertotto, Gustavo W.; Balbinot, Eduardo; Schilling, Manuel E.; Gervasoni, Fernanda

    2016-09-01

    Patagonia, in the Southern Andes, is one of the few locations where interactions between the oceanic and continental lithosphere can be studied due to subduction of an active spreading ridge beneath the continent. In order to characterize the noble gas composition of Patagonian subcontinental lithospheric mantle (SCLM), we present the first noble gas data alongside new lithophile (Sr-Nd-Pb) isotopic data for mantle xenoliths from Pali-Aike Volcanic Field and Gobernador Gregores, Southern Patagonia. Based on noble gas isotopic compositions, Pali-Aike mantle xenoliths represent intrinsic SCLM with higher (U + Th + K)/(3He, 22Ne, 36Ar) ratios than the mid-ocean ridge basalt (MORB) source. This reservoir shows slightly radiogenic helium (3He/4He = 6.84-6.90 RA), coupled with a strongly nucleogenic neon signature (mantle source 21Ne/22Ne = 0.085-0.094). The 40Ar/36Ar ratios vary from a near-atmospheric ratio of 510 up to 17700, with mantle source 40Ar/36Ar between 31100-6800+9400 and 54000-9600+14200. In addition, the 3He/22Ne ratios for the local SCLM endmember, at 12.03 ± 0.15 to 13.66 ± 0.37, are higher than depleted MORBs, at 3He/22Ne = 8.31-9.75. Although asthenospheric mantle upwelling through the Patagonian slab window would result in a MORB-like metasomatism after collision of the South Chile Ridge with the Chile trench ca. 14 Ma, this mantle reservoir could have remained unhomogenized after rapid passage and northward migration of the Chile Triple Junction. The mantle endmember xenon isotopic ratios of Pali-Aike mantle xenoliths, which is first defined for any SCLM-derived samples, show values indistinguishable from the MORB source (129Xe/132Xe =1.0833-0.0053+0.0216 and 136Xe/132Xe =0.3761-0.0034+0.0246). The noble gas component observed in Gobernador Gregores mantle xenoliths is characterized by isotopic compositions in the MORB range in terms of helium (3He/4He = 7.17-7.37 RA), but with slightly nucleogenic neon (mantle source 21Ne/22Ne = 0.065-0.079). We

  18. Ticks infesting humans in Northern Misiones, Argentina.

    Science.gov (United States)

    Lamattina, Daniela; Nava, Santiago

    2016-01-01

    This work presents records of ticks infesting humans in northern Misiones Province, Argentina. Also, notes on potential transmission of tick-borne pathogens are included. A total of 282 ticks attached to researchers were collected and identified by their morphological characters. Eight tick species were found: Amblyomma brasiliense, Amblyomma coelebs, Amblyomma dubitatum, Amblyomma incisum, Amblyomma ovale, Haemaphysalis juxtakochi, Rhipicephalus sanguineus and Rhipicephalus microplus. Some of these species as A. dubitatum, A. ovale and R. sanguineus have been found infected with spotted fever group rickettsiae pathogenic to humans in Brazil and Argentina. The potential role as vectors of humans pathogens of the ticks found attached to humans in this study is discussed.

  19. El desarrollo nuclear de Argentina y Brasil

    OpenAIRE

    Quintanar, Silvia; Romegialli, Mónica

    2004-01-01

    En el Cono Sur Latinoamericano, Brasil y Argentina han concluido en materia de energía atómica una serie de acuerdos bilaterales, con jerarquía de tratados vinculatorios, que aseguran el uso exclusivamente pacífico de la energía nuclear. En los años 90 se profundiza el fortalecimiento de la confianza mutua, los gobiernos de Carlos Menem, en Argentina, Collor de Melho, Itamar Franco y Fernando H. Cardoso, en Brasil, siguen los lineamientos de las grandes potencias y en particular de Estados Un...

  20. Neogene kinematic history of Nazca-Antarctic-Phoenix slab windows beneath Patagonia and the Antarctic Peninsula

    Science.gov (United States)

    Breitsprecher, Katrin; Thorkelson, Derek J.

    2009-01-01

    The Patagonian slab window is a subsurface tectonic feature resulting from subduction of the Nazca-Antarctic spreading-ridge system (Chile Rise) beneath southern South America. The geometry of the slab window had not been rigorously defined, in part because of the complex nature of the history of ridge subduction in the southeast Pacific region, which includes four interrelated spreading-ridge systems since 20 Ma: first, the Nazca-Phoenix ridge beneath South America, then simultaneous subduction of the Nazca-Antarctic and the northern Phoenix-Antarctic spreading-ridge systems beneath South America, and the southern Phoenix-Antarctic spreading-ridge system beneath Antarctica. Spreading-ridge paleo-geographies and rotation poles for all relevant plate pairs (Nazca, Phoenix, Antarctic, South America) are available from 20 Ma onward, and form the mathematical basis of our kinematic reconstruction of the geometry of the Patagonia and Antarctic slab windows through Neogene time. At approximately 18 Ma, the Nazca-Phoenix-Antarctic oceanic (ridge-ridge-ridge) triple junction enters the South American trench; we recognize this condition as an unstable quadruple junction. Heat flow at this junction and for some distance beneath the forearc would be considerably higher than is generally recognized in cases of ridge subduction. From 16 Ma onward, the geometry of the Patagonia slab window developed from the subduction of the trailing arms of the former oceanic triple junction. The majority of the slab window's areal extent and geometry is controlled by the highly oblique (near-parallel) subduction angle of the Nazca-Antarctic ridge system, and by the high contrast in relative convergence rates between these two plates relative to South America. The very slow convergence rate of the Antarctic slab is manifested by the shallow levels achieved by the slab edge (< 45 km); thus no point on the Antarctic slab is sufficiently deep to generate "normal" mantle-derived arc-type magmas

  1. Fire history in western Patagonia from paired tree-ring fire-scar and charcoal records

    Directory of Open Access Journals (Sweden)

    A. Holz

    2011-10-01

    Full Text Available Fire history reconstructions are typically based on tree ages and tree-ring fire scars or on charcoal in sedimentary records from lakes or bogs, but rarely on both. In this study of fire history in western Patagonia (47–48° S in southern South America (SSA we compared three sedimentary charcoal records collected in bogs with tree-ring fire-scar data collected at 13 nearby sample sites. We examined the temporal and spatial correspondence between the two fire proxies and also compared them to published charcoal records from distant sites in SSA, and with published proxy reconstructions of regional climate variability and large-scale climate modes. Two of our three charcoal records show fire activity for the last 4ka yrs and one for the last 11 ka yr. For the last ca. 400 yr, charcoal accumulation peaks tend to coincide with high fire activity in the tree-ring fire scar records, but the charcoal records failed to detect some of the fire activity recorded by tree rings. Potentially, this discrepancy reflects low-severity fires that burn in herbaceous and other fine fuels without depositing charcoal in the sedimentary record. Periods of high fire activity tended to be synchronous across sample areas, across proxy types, and with proxy records of regional climatic variability as well as major climate drivers. Fire activity throughout the Holocene in western Patagonia has responded to regional climate variation affecting a broad region of southern South America that is teleconnected to both tropical- and high-latitude climate drivers – El Nino-Southern Oscillation and the Southern Annular Mode. An early Holocene peak in fire activity pre-dates any known human presence in our study area, and consequently implicates lightning as the ignition source. In contrast, the increased fire activity during the 20th century, which was concomitantly recorded by charcoal from all the sampled bogs and at all fire-scar sample sites, is attributed to human

  2. Fire history in western Patagonia from paired tree-ring fire-scar and charcoal records

    Directory of Open Access Journals (Sweden)

    A. Holz

    2012-03-01

    Full Text Available Fire history reconstructions are typically based on tree ages and tree-ring fire scars or on charcoal in sedimentary records from lakes or bogs, but rarely on both. In this study of fire history in western Patagonia (47–48° S in southern South America (SSA we compared three sedimentary charcoal records collected in bogs with tree-ring fire-scar data collected at 13 nearby sample sites. We examined the temporal and spatial correspondence between the two fire proxies and also compared them to published charcoal records from distant sites in SSA, and with published proxy reconstructions of regional climate variability and large-scale climate modes. Two of our three charcoal records record fire activity for the last 4 ka yr and one for the last 11 ka yr. For the last ca. 400 yr, charcoal accumulation peaks tend to coincide with high fire activity in the tree-ring fire scar records, but the charcoal records failed to detect some of the fire activity recorded by tree rings. Potentially, this discrepancy reflects low-severity fires that burn in herbaceous and other fine fuels without depositing charcoal in the sedimentary record. Periods of high fire activity tended to be synchronous across sample areas, across proxy types, and with proxy records of regional climatic variability as well as major climate drivers. Fire activity throughout the Holocene in western Patagonia has responded to regional climate variation affecting a broad region of southern South America that is teleconnected to both tropical- and high-latitude climate drivers-El Niño-Southern Oscillation and the Southern Annular Mode. An early Holocene peak in fire activity pre-dates any known human presence in our study area, and consequently implicates lightning as the ignition source. In contrast, the increased fire activity during the 20th century, which was concomitantly recorded by charcoal from all the sampled bogs and at all fire-scar sample sites, is attributed to human-set fires

  3. Range expansion and prey use of American mink in Argentinean Patagonia: dilemmas for conservation

    OpenAIRE

    Fasola, Laura; Muzio, Juan; Chehébar, Claudio; Cassini, Marcelo; Macdonald, David W.

    2010-01-01

    Abstract Following the establishment of American mink farms outside North America, the species has successfully invaded Europe and South America, and in some places, their presence demonstrably threatens native biodiversity. We surveyed for mink signs along the Andean Patagonian forest in Argentina from 38?52? S to 54?52? S, revealing that their range has now expanded to span 800 km of contiguous occupation on the continent including several types of wetlands and has also colonised...

  4. 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 (Swed