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Sample records for cbvf northern patagonia

  1. 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.

  2. 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 %.

  3. 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.

  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. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. New precipitation and temperature grids for northern Patagonia: Advances in relation to global climate grids

    Science.gov (United States)

    Bianchi, Emilio; Villalba, Ricardo; Viale, Maximiliano; Couvreux, Fleur; Marticorena, Rocio

    2016-02-01

    Climate data of mean monthly temperature and total monthly precipitation compiled from different sources in northern Patagonia were interpolated to 20-km resolution grids over the period 1997-2010. This northern Patagonian climate grid (NPCG) improves upon previous gridded products in terms of its spatial resolution and number of contributing stations, since it incorporates 218 and 114 precipitation and temperature records, respectively. A geostatistical method using surface elevation from a Digital Elevation Model (DEM) as the ancillary variable was used to interpolate station data into even spaced points. The maps provided by NPCG are consistent with the broad spatial and temporal patterns of the northern Patagonian climate, showing a comprehensive representation of the latitudinal and altitudinal gradients in temperature and precipitation, as well as their related patterns of seasonality and continentality. We compared the performance of NPCG and various other datasets available to the climate community for northern Patagonia. The grids used for the comparison included those of the Global Precipitation Climatology Project, ERAInterim, Climate Research Unit (University of East Anglia), and University of Delaware. Based on three statistics that quantitatively assess the spatial coherence of gridded data against available observations (bias, MAE, and RMSE), NPCG outperforms other global grids. NPCG represents a useful tool for understanding climate variability in northern Patagonia and a valuable input for regional models of hydrological and ecological processes. Its resolution is optimal for validating data from the general circulation models and working with raster data derived from remote sensing, such as vegetation indices.

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

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    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.

  9. [Cercarial dermatitis of bathers in northern Argentine Patagonia].

    Science.gov (United States)

    Veleizán, Aylén A; Flores, Verónica R; Viozzi, Gustavo P

    2016-01-01

    The cercarial dermatitis is a zoonotic, summer, skin-disease, caused by a swimming larva (cercaria) of a schistosomatid trematode. This larva accidentally penetrates the skin of people in the water, causing an allergic reaction, which is not always reported in health centers, so it is difficult to determine its incidence. Cases have been registered worldwide, including Argentina, although the epidemiological studies were performed only in the Northern Hemisphere. In this survey the epidemiology of cercarial dermatitis was studied in three Patagonian lakes watering places, Pellegrini, Mari Menuco, and Puelo, where surveys were conducted during summers of 2012-2013 and 2013-2014. The risk factors were analyzed and grouped in "personal characteristics", "use of the recreational resource", and "prevention measures". At the Pellegrini Lake, the people's sensitivity included in "personal characteristics" was the only determining factor for the occurrence of this zoonosis, mean while in Mari Menuco Lake, the bathing time and distance from the coast, and the use of lotions would affect the occurrence of swimmer's itch. In Puelo Lake, no cases were recorded during the study period. PMID:26826989

  10. A promising location in Patagonia for paleoclimate and paleoenvironmental reconstructions revealed by shallow firn core from Monte San Valentin (Northern patagonia Icefield, Chile)

    DEFF Research Database (Denmark)

    Vimeux, F.; de Angelis, M.; Ginot, P.;

    2008-01-01

    Southern Hemisphere. In this framework, a 15.3-m long shallow firn core has been extracted in March 2005 from the summit plateau of Monte San Valentín (3747 m, 46°35'S, 73°19'W) in the Northern Patagonia Icefield to test its potential for paleoclimate and paleoenvironmental reconstructions. The firn...... temperature is -11.9°C at 10-m depth allowing to expect well preserved both chemical and isotopic signals, unperturbed by water percolation. The dating of the core, on the basis of a multi-proxy approach combining annual layer counting and radionuclide measurements, shows that past environment and climate can...

  11. 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

  12. Shell shape variation in the Nassariid Buccinanops globulosus in northern Patagonia

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    Avaca, María Soledad; Narvarte, Maite; Martín, Pablo; van der Molen, Silvina

    2013-09-01

    Morphological variation among natural populations is a phenomenon commonly observed in marine invertebrates and well studied, particularly, in shelled gastropods. The nassariid Buccinanops globulosus is interesting to study shell shape variation because it exhibits strong interpopulation differences in life history features, including maximum size, fecundity and growth rate. In this study, we examined the pattern of variation in size and shell shape among populations and between sexes of B. globulosus (Bahía San Antonio 40°29'S 63°01'W, Playa Villarino 40°45'S 64°40'W and Bahía Nueva 42°46'S 65°02'W). In particular, we used geometric morphometric techniques to test: (1) whether the two components of shell morphology (size and shape) are independent and (2) whether shape differences between sexes are consistently found among populations, regardless of their body sizes. Our results show shell shape variation between the populations of B. globulosus of northern Patagonia. Intra-specific shell shape variation is affected by body size, indicating allometry. Regardless of the size differences, individuals from Playa Villarino have high-spired shells, and shorter apertures and wider columellar area than individuals from the other populations. Also, sex-related shape differences were consistently found at each population, thus suggesting a common sexual dimorphism in shell morphology for this species. The functional significance of the variability found is discussed in terms of the flexibility of developmental programmes for morphology as well as the evolution of phenotypic plasticity.

  13. Heavy metals bio indication in northern Patagonia lakes, Argentina, using native mussel Diplodon sp

    International Nuclear Information System (INIS)

    Full text: Native mussels Diplodon chilensis were sampled from lakes comprised in Nahuel Huapi National Park, Northern Patagonia, Argentina, and surrounding areas, in order to evaluate heavy metal distribution in the region, and to assess the contribution that this compartment of the trophic web transfers to the circulation of these elements in the food chain. Filter feeding organisms such as the hard shell Diplodon chilensis are ideal subjects for the study of bioaccumulation of contaminants in view of their feeding habits which imply that they become key link elements in the transfer of energy in the form of phyto, zooplankton and organic particulate matter from the water column into the water bodies food webs. The concentration of potential pollutants or elements that could affect human health or wildlife, namely Sb, Ag, As, Cr, Hg, and Se were determined in pooled samples of 15 similar length individuals, by Instrumental Neutron Activation Analysis. Digestive glands were analysed separately from soft tissues. Geological tracers Sc, Ta, Th, U, and Rare Earth elements, were also determined in order to discriminate the elements associated to detritical particulate matter included in mussels bodies from those incorporated by the organisms. No relevant differences were observed between elemental concentration in digestive glands and whole soft tissues except for Hg contents, that ranged from 0.7 to 12 μg.g-1 dry weight in digestive glands, and from 0.2 to 0.9 μg.g-1 dry weight in whole soft tissues. There was no correlation between Hg contents in both types of samples. Whole soft tissues were selected for long-term bio indication since the time residence of Hg in digestive gland is shorter and could not represent steady state conditions. (author)

  14. Ice elevation and areal changes of glaciers from the Northern Patagonia Icefield, Chile

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    Rivera, Andrés; Benham, Toby; Casassa, Gino; Bamber, Jonathan; Dowdeswell, Julian A.

    2007-10-01

    High thinning rates (up to - 4.0 ± 0.97 m a - 1 ) have been measured at Campo de Hielo Patagónico Norte (CHN) or Northern Patagonia Icefield, Chile between 1975 and 2001. Results have been obtained by comparing a Digital Elevation Model (DEM) derived from regular cartography compiled by Instituto Geográfico Militar of Chile (IGM) based upon 1974/1975 aerial photographs and a DEM generated from Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) satellite images acquired in September 2001. A complete cloud-free Landsat ETM+ satellite image mosaic acquired in March 2001 was used to update the available glacier inventory of the CHN, including all glaciers larger than 0.5 km 2 (48 new glaciers). A new delineation of ice divides was also performed over the accumulation areas of glaciers sharing the high plateau where the existing regular cartography exhibits poor coverage of topographic information. This updated glacier inventory produced a total ice area for 2001 of 3953 km 2, which represents a decrease of 3.4 ± 1.5% (140 ± 61 km 2 of ice) with respect to the total ice area of the CHN in 1979 calculated from a Landsat MSS satellite image. Almost 62% of the total area change between 1979 and 2001 took place in glaciers located at the western margin of the CHN, where the maximum area loss was experienced by Glaciar San Quintín with 33 km 2. At the southern margin, Glaciar Steffen underwent the largest ice-area loss (12 km 2 or 2.6% of the 1979 area), whilst at the eastern margin the greatest area loss took place in Glaciares Nef (7.9 km 2, 5.7% of the 1979 area) and Colonia (9.1 km 2, 2.7% of the 1979 area). At the northern margin of the CHN the lower debris-covered ablation area of Glaciar Grosse collapsed into a new freshwater lake formed during the late 1990s. The areal changes measured at the CHN are much larger than previously estimated due to the inclusion of changes experienced in the accumulation areas. The CHN as a whole is

  15. 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.

  16. 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.

  17. 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.

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

    OpenAIRE

    Stephen J. Brooks; Luis M. Hernández; Julieta Massaferro; Gustavo R. Spinelli; Malcolm Penn

    2009-01-01

    This project was funded from September 2006 for three years by the British Government's Darwin Initiative programme. The focus of our project is the study of aquatic insects from Nahuel Huapi National Park (NHNP) in Patagonia, Argentina. The park includes a wide range of wetlands, including montane streams, lowland lakes and marshes, distributed within temperate rainforest and arid steppe. The material will be identified and stored in a fully referenced and accessible collection at La Plata M...

  19. Are the oxygen isotopic compositions of Fitzroya cupressoides and Nothofagus pumilio cellulose promising proxies for climate reconstructions in northern Patagonia?

    Science.gov (United States)

    Lavergne, Aliénor; Daux, Valérie; Villalba, Ricardo; Pierre, Monique; Stievenard, Michel; Vimeux, Françoise; Srur, Ana Marina

    2016-03-01

    Tree ring δ18O chronologies from two native species (Fitzroya cupressoides and Nothofagus pumilio) in northern Patagonia were developed to assess their potential for paleoclimate reconstructions. The five annually resolved cellulose δ18O chronologies (two for F. cupressoides and three for N. pumilio) are located on the Andes along the steep west-to-east precipitation gradient. Over the common 60 years long interval, the five site-δ18Ocell chronologies exhibit a strong common signal as indicated by the significant mean intercorrelation (r = 0.61, p < 0.05) and the high percentage (65%) of total variance explained by the first empirical orthogonal function. Although correlation analyses reveal that the two mean species-δ18Ocell chronologies are mainly modulated by December-May temperature, the N. pumilio chronology shows a greater sensitivity to record temperature variations (r = 0.57, p < 0.05). The δ18Ocell of N. pumilio contains a regional temperature signal representative of a large area in southern South America under the influence of the Southern Annular Mode. This study indicates that δ18Ocell in N. pumilio is a promising proxy to reconstruct past variations in temperature in South America south of 38°S.

  20. New records of late Holocene tephras from Lake Futalaufquen (42.8°S), northern Patagonia

    Science.gov (United States)

    Daga, Romina; Ribeiro Guevara, Sergio; Arribére, María

    2016-03-01

    In regions with limited knowledge of the historical volcanic record, like remote areas in the Andean Southern Volcanic Zone, the definition of reliable age-depth models for lake sequences represents a valuable tool for tephra layers dating. In Lake Futalaufquen (42.8°S), Northern Patagonia, a short sedimentary sequence was extracted after the AD 2008 Chaitén eruption with the purpose to analyze the records of volcanic eruptions at these poorly studied latitudes. The sequence was dated by 210Pb, 137Cs, and 14C techniques. Five tephras were identified for the last 1600 years, restricted to the last 5 centuries. Sedimentology, morphology, and geochemical properties allowed the characterization of the tephras and their correlation with tephras recently identified proximal to the sources, mainly from Chaitén and Huequi volcanoes, and Michinmahuida accessory cones, representing the first distal records reported of these tephras. Furthermore, tephras modeled ages obtained by the sequence age-depth model shrink the ages for the volcanic events, like a potential cycle of activity from Michinmauida accessory cones during AD 1530 ± 55, one eruption from Huequi volcano at AD 1695 ± 50, and a possible recent eruption from Chaitén at AD 1775 ± 40. Additionally, the work contributes to improve the regional volcanic records knowledge, basic for volcanic hazard assessment.

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

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

    2010-08-01

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

  2. Late Holocene covariability of the southern westerlies and sea surface temperature in northern Chilean Patagonia

    Science.gov (United States)

    Bertrand, Sébastien; Hughen, Konrad; Sepúlveda, Julio; Pantoja, Silvio

    2014-12-01

    The climate of Chilean Patagonia is strongly influenced by the southern westerlies, which control the amount and latitudinal distribution of precipitation in the southern Andes. In austral summer, the Southern Westerly Wind Belt (SWWB) is restricted to the high latitudes. It expands northward in winter, which results in a strong precipitation seasonality between ˜35 and 45°S. Here, we present a new precipitation seasonality proxy record from Quitralco fjord (46°S), where relatively small latitudinal shifts of the SWWB result in large changes in precipitation seasonality. Our 1400 yr record is based on sedimentological and geochemical data obtained on a sediment core collected in front of a small river that drains the Patagonian Andes, which makes this site particularly sensitive to changes in river discharge. Our results indicate Fe/Al and Ti/Al values that are low between 600 and 1200 CE, increasing at 1200-1500 CE, and high between 1500 and 1950 CE. Increasing Fe/Al and Ti/Al values reflect a decrease in mean sediment grain-size from 30 to 20 μm, which is interpreted as a decrease in seasonal floods resulting from an equatorward shift of the SWWB. Our results suggest that, compared to present-day conditions, the SWWB was located in a more poleward position before 1200 CE. It gradually shifted towards the equator in 1200-1500 CE, where it remained in a sustained position until 1950 CE. This pattern is consistent with most precipitation records from central and southern Chile. The comparison of our record with published regional sea surface temperature (SST) reconstructions for the late Holocene shows that equatorward shifts of the SWWB are systematically coeval with decreasing SSTs and vice versa, which resembles fluctuations over glacial-interglacial timescales. We argue that the synchronicity between SST and SWWB changes during the last 1400 years represents the response of the SWWB to temperature changes in the Southern Hemisphere.

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

    Directory of Open Access Journals (Sweden)

    Stephen J. Brooks

    2009-06-01

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

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

    Science.gov (United States)

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

    2016-01-01

    Bioprospecting natural products in marine bacteria from fjord environments are attractive due to their unique geographical features. Although, Actinobacteria are well known for producing a myriad of bioactive compounds, investigations regarding fjord-derived marine Actinobacteria are scarce. In this study, the diversity and biotechnological potential of Actinobacteria isolated from marine sediments within the Comau fjord, in Northern Chilean Patagonia, were assessed by culture-based approaches. The 16S rRNA gene sequences revealed that members phylogenetically related to the Micrococcaceae, Dermabacteraceae, Brevibacteriaceae, Corynebacteriaceae, Microbacteriaceae, Dietziaceae, Nocardiaceae, and Streptomycetaceae families were present at the Comau fjord. A high diversity of cultivable Actinobacteria (10 genera) was retrieved by using only five different isolation media. Four isolates belonging to Arthrobacter, Brevibacterium, Corynebacterium and Kocuria genera showed 16S rRNA gene identity <98.7% suggesting that they are novel species. Physiological features such as salt tolerance, artificial sea water requirement, growth temperature, pigmentation and antimicrobial activity were evaluated. Arthrobacter, Brachybacterium, Curtobacterium, Rhodococcus, and Streptomyces isolates showed strong inhibition against both Gram-negative Pseudomonas aeruginosa, Escherichia coli and Salmonella enterica and Gram-positive Staphylococcus aureus, Listeria monocytogenes. Antimicrobial activities in Brachybacterium, Curtobacterium, and Rhodococcus have been scarcely reported, suggesting that non-mycelial strains are a suitable source of bioactive compounds. In addition, all strains bear at least one of the biosynthetic genes coding for NRPS (91%), PKS I (18%), and PKS II (73%). Our results indicate that the Comau fjord is a promising source of novel Actinobacteria with biotechnological potential for producing biologically active compounds. PMID:27486455

  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. A 1500 yr warm-season temperature record from varved Lago Plomo, Northern Patagonia (47° S) and implications for the Pacific Decadal Oscillation (PDO)

    Science.gov (United States)

    Elbert, J.; Jacques-Coper, M.; Van Daele, M.; Urrutia, R.; Grosjean, M.

    2013-04-01

    High-resolution records of calibrated proxy data for the past 2000 yr are fundamental to place current changes into the context of pre-industrial natural forced and unforced variability. Although the need for regional spatially explicit comprehensive reconstructions is widely recognized, the proxy data sources are still scarce, particularly for the Southern Hemisphere and South America. We provide a 1500 yr long warm season temperature record from varved Lago Plomo, a proglacial lake of the Northern Patagonian Ice field in southern Chile (46°59' S, 72°52' W, 203 m). The thickness of the bright summer sediment layer relative to the dark winter layer (measured as total brightness; % reflectance 400-730 nm) is calibrated against warm season SONDJF temperature (1900-2009; r = 0.58, p(aut) = 0.056, RE = 0.52; CE = 0.15, RMSEP = 0.28 °C; five-year triangular filtered data). In Lago Plomo, warm summer temperatures lead to enhanced glacier melt and suspended sediment transport, which results in a thicker light summer layer and to brighter sediments (% total brightness). Although Patagonia shows pronounced regional differences in decadal temperature trends and variability, the 1500 yr temperature reconstruction from Lago Plomo compares favourably with other regional/continental temperature records but also emphasizes significant regional differences for which no data and information existed so far. The reconstruction shows pronounced sub-decadal-multi-decadal variability with cold phases in the 5th, 7th and 9th centuries, during parts of the Little Ice Age chronozone (16th and 18th centuries) and in the beginning of the 20th century. The most prominent warm phase is the 19th century which is as warm as the second half of the 20th century, emphasizing a delayed recent global warming in the Southern Hemisphere. The comparison between winter precipitation and summer temperature (inter-seasonal coupling) from Lago Plomo reveals alternating phases with parallel and

  8. 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

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    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

  9. Patagonia: nature and territories

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    Alejandro Fabián Schweitzer

    2014-12-01

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

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

    Science.gov (United States)

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

    2015-10-01

    Wool production oriented sheep keeping is the most important rural activity in Patagonia, Argentina, followed by goat and at a lower extent cattle production. The existing perception on the smallholder production systems from most decision makers (e.g., policy) is that they are marginal, with low productivity and have negative returns. Since the Argentinean economic scenario has changed drastically in the last decade, the aim of this study was to analyze the economic and productive contribution of different livestock species in smallholdings. The results showed that the post-1990's economic scenario turned most smallholder livestock systems to have positive economic performance, but there were still productive restrictions that limited to fully benefit from these favorable circumstances. Goats were the most profitable livestock due to their higher productive performance, followed by sheep and cattle, with poorer performances. A strong cooperation between the intervention programs and research institutions is recommended to overcome the current production bottlenecks, by focusing on cattle and sheep production systems. PMID:26089256

  11. Evolution of the Neogene Andean foreland basins of the Southern Pampas and Northern Patagonia (34°-41°S), Argentina

    Science.gov (United States)

    Folguera, Alicia; Zárate, Marcelo; Tedesco, Ana; Dávila, Federico; Ramos, Victor A.

    2015-12-01

    The Pampas plain (30°-41°S) has historically been considered as a sector that evolved independently from the adjacent Andean ranges. Nevertheless, the study of the Pampas showed that it is reasonable to expect an important influence from the Andes into the extraandean area. The Pampas plain can be divided into two sectors: the northern portion, adjacent to the Pampean Ranges, has been studied by Davila (2005, 2007, 2010). The southern sector (34°-41°S) is the objective of the present work. The study of this area allowed to characterize two separate foreland basins: the Southern Pampa basin and the Northern Patagonian basin. The infill is composed of Late Miocene and Pliocene units, interpreted as distal synorogenic sequences associated with the late Cenozoic Andean uplift at this latitudinal range. These foreland basins have been defined based on facies changes, distinct depositional styles, along with the analysis of sedimentary and isopach maps. The basins geometries are proposed following De Celles and Gilles (1996) taking into account the infill geometry, distribution and grain size. In both cases, these depocenters are located remarkably far away from the Andean tectonics loads. Therefore they cannot be explained with short-wave subsidence patterns. Elastic models explain the tectonic subsidence in the proximal depocenters but fail to replicate the complete distal basins. These characteristics show that dynamic subsidence is controlling the subsidence in the Southern Pampas and Northern Patagonian basins.

  12. 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...

  13. The first geological mapof Patagonia

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    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.

  14. patagonia chilena. Punta Arenas

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    Luis Inostroza Pino

    2008-01-01

    Full Text Available Este trabajo trata sobre la forma de ocupación espacial de la región de magallanes, dado por el patrón de ocupación nativo, que corresponde al de las etnias locales, y el patrón que implanta la República a partir de 1843. Razones del contexto mundial apoyadas por adecuadas decisiones a nivel local, son las que permitieron el desarrollo de la Patagonia y de la ciudad de Punta Arenas fundamentalmente hasta fines del siglo XIX. La iniciación del tráfico regular entre Europa y el Pacífico, con recalada obligada en la colonia, y las medidas de Puerto libre y de incentivo a la inmigración de colonos nacionales y extranjeros, influirán decisivamente en ese desarrollo. El modesto pueblo se transforma en un importante centro urbano.

  15. 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

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

    OpenAIRE

    Patricio De los Ríos-Escalante; Enrique Hauenstein; Patricio Acevedo; Mario Romero-Miéres; Ivan Pandourski

    2012-01-01

    Chilean Patagonia has protected mountainous areas with evergreen native forests; in which the lakes and rivers, of volcanic or glacial origin, are oligotrophic. In Bulgaria, there are mountainous zones with native forests and associated lakes of volcanic origin. The aim of the present study is to carry out a preliminary comparison of zooplanktonic crustaceans in lake ecosystems associated with native forests of Chilean Patagonia and of Bulgarian mountains. The study revealed that the lakes st...

  17. 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

  18. Un cráneo del norte de Patagonia con modificaciones postmórtem: Aproximación mediante técnicas no invasivas A skull from northern Patagonia with postmortem modifications: an approach using non-invasive techniques

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    Mariano Del Papa

    2011-12-01

    Full Text Available En el contexto de la puesta en valor de las colecciones de restos óseos humanos del Museo de La Plata se halló un cráneo con evidencias de un complejo tratamiento post mórtem desconocido hasta el momento. Con el fin de obtener información acerca de la procedencia exacta y el contexto de inhumación del hallazgo, se implementaron una serie de técnicas y metodologías de análisis (revisión bibliográfica, análisis tafonómico y análisis de las huellas corte, que promueven al mismo tiempo la conservación del registro bioarqueológico (aplicación de técnicas de imágenes de carácter no invasivo. Como resultado, se presenta una práctica mortuoria particular y sin antecedentes en la bibliografía para la región norpatagónica. Asimismo, se revaloriza el tratamiento, preservación y estudio de colecciones bioarqueológicas.A skull with evidence of a form of mortuary disposal unknown in the study area was found in a human osteological collection from the Museo de La Plata. In order to get information about the exact provenance and context of discovery of the burial a number of techniques and methodologies of analysis were implemented (literature review, analysis of taphonomic and cut mark traces while promoting the conservation of the bioarchaeological record (by means of the application of non-invasive imaging techniques. As a result, a novel mortuary practice without precedents in the bibliography of north Patagonia is presented. Furthermore, the crucial importance of the treatment, preservation and study of bioarchaeological collections is emphasized.

  19. Late Quaternary evolution of Lago Castor (Chile, 45.6°S): Timing of the deglaciation in northern Patagonia and evolution of the southern westerlies during the last 17 kyr

    Science.gov (United States)

    Van Daele, Maarten; Bertrand, Sébastien; Meyer, Inka; Moernaut, Jasper; Vandoorne, Willem; Siani, Giuseppe; Tanghe, Niels; Ghazoui, Zakaria; Pino, Mario; Urrutia, Roberto; De Batist, Marc

    2016-02-01

    Even though Patagonia is ideally located to study climate of the southern mid-latitudes, many questions on the late Quaternary climate evolution remain unresolved. The timing of maximum glacier extent is still uncertain in vast areas, and the postglacial evolution of the Southern Westerly Wind Belt (SWWB) remains highly debated. Here, we study the sedimentary infill of a glacigenic lake (Lago Castor; 45.6°S, 71.8°W) located at the leeside of the Andes in Chilean Patagonia to i) reconstruct the deglacial evolution of the eastern flank of the Patagonian Ice Sheet (PIS), and ii) discuss postglacial changes in wind strength at a critical location where westerly wind records are critically lacking. A dense grid of high-resolution reflection-seismic data was used to reconstruct the large-scale infill history of the lake, and a radiocarbon dated sediment core penetrating all lacustrine seismic units, was retrieved. Results indicate that the deglaciation of the lake basin and its catchment occurred no later than ∼28 cal kyr BP (i.e. an early LGM), but possibly even already after MIS 4. Afterwards, the Lago Castor area was covered by a large proglacial lake that drained - possibly through an outburst flood - when the PIS outlet glaciers retreated to a critical location. Subsequently, very dry conditions caused the lake to desiccate, as evidenced by an unconformity visible on the seismic profiles and in the sediment core. This dry period likely resulted from the increased orographic effect of the PIS-covered Andes, accompanied by weaker westerlies. From ∼20 kyr BP onwards, the combination of a shrinking PIS and a southward shift of the SWWB resulted in increased precipitation, which caused the lake level to rise. After ∼17 cal kyr BP, lake sedimentation was more directly influenced by the southern westerlies, with the formation of sediment drifts resulting from strong bottom current during periods of intense westerly winds. Our results suggest a progressive increase

  20. Late Quaternary evolution of Lago Castor (Chile, 45.6°S): Timing of the deglaciation in northern Patagonia and evolution of the southern westerlies during the last 17 kyr

    Science.gov (United States)

    Van Daele, Maarten; Bertrand, Sébastien; Meyer, Inka; Moernaut, Jasper; Vandoorne, Willem; Siani, Giuseppe; Tanghe, Niels; Ghazoui, Zakaria; Pino, Mario; Urrutia, Roberto; De Batist, Marc

    2016-02-01

    Even though Patagonia is ideally located to study climate of the southern mid-latitudes, many questions on the late Quaternary climate evolution remain unresolved. The timing of maximum glacier extent is still uncertain in vast areas, and the postglacial evolution of the Southern Westerly Wind Belt (SWWB) remains highly debated. Here, we study the sedimentary infill of a glacigenic lake (Lago Castor; 45.6°S, 71.8°W) located at the leeside of the Andes in Chilean Patagonia to i) reconstruct the deglacial evolution of the eastern flank of the Patagonian Ice Sheet (PIS), and ii) discuss postglacial changes in wind strength at a critical location where westerly wind records are critically lacking. A dense grid of high-resolution reflection-seismic data was used to reconstruct the large-scale infill history of the lake, and a radiocarbon dated sediment core penetrating all lacustrine seismic units, was retrieved. Results indicate that the deglaciation of the lake basin and its catchment occurred no later than ˜28 cal kyr BP (i.e. an early LGM), but possibly even already after MIS 4. Afterwards, the Lago Castor area was covered by a large proglacial lake that drained - possibly through an outburst flood - when the PIS outlet glaciers retreated to a critical location. Subsequently, very dry conditions caused the lake to desiccate, as evidenced by an unconformity visible on the seismic profiles and in the sediment core. This dry period likely resulted from the increased orographic effect of the PIS-covered Andes, accompanied by weaker westerlies. From ˜20 kyr BP onwards, the combination of a shrinking PIS and a southward shift of the SWWB resulted in increased precipitation, which caused the lake level to rise. After ˜17 cal kyr BP, lake sedimentation was more directly influenced by the southern westerlies, with the formation of sediment drifts resulting from strong bottom current during periods of intense westerly winds. Our results suggest a progressive increase in

  1. Oceanography of the Chilean Patagonia

    Science.gov (United States)

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

    2011-03-01

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

  2. 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.

  3. 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

  4. 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.

  5. 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

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

    Directory of Open Access Journals (Sweden)

    N Rubén Cúneo

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

  7. The Argentinean Patagonia and the Martian landscape

    Science.gov (United States)

    Pacifici, Andrea

    2009-05-01

    Throughout the Cenozoic Era, the geological history of the Argentinean Patagonia was dominated by basaltic volcanism and glacial and periglacial environments. Several geological and geomorphological processes that concurred to the sculpting of the landscape of this area could have been similar to those responsible of the shaping of the Martian surface. In this work a survey of some high-resolution satellite images of the Argentinean Patagonia is performed in order to identify possible geomorphological analogs of the Martian surface. Several morphologies that resemble Martian features are presented and discussed. They consist of proglacial and periglacial features, relatively small circular depressions, gullies, fan-deltas, eolian streaks, and diluvial dunes. Results suggest that the Argentinean Patagonia appears to consist of an interesting terrestrial analog for the Martian landscape. Furthermore, the study area shows to be interesting in order to test robotic instruments and human missions equipment, to train astronauts of future human expeditions to Mars, and to perform astrobiological experiments.

  8. Presence of Pleurotus ostreatus in Patagonia, Argentina.

    Science.gov (United States)

    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

  9. 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

  10. Contribution of the Patagonia Icefields of South America to sea level rise.

    OpenAIRE

    E. Rignot; A. Rivera; G. Casassa

    2003-01-01

    Digital elevation models of the Northern and Southern Patagonia Icefields of South America generated from the 2000 Shuttle Radar Topography Mission were compared with earlier cartography to estimate the volume change of the largest 63 glaciers. During the period 1968/1975-2000, these glaciers lost ice at a rate equivalent to a sea level rise of 0.042 +/- 0.002 millimeters per year. In the more recent years 1995-2000, average ice thinning rates have more than doubled to an equivalent sea level...

  11. Breeding biology of Grey eagle-buzzard (Geranoaetus melanoleucos) population in Patagonia

    OpenAIRE

    Hiraldo, F.; Donázar, José A.; Ceballos, Olga; Travaini, Alejandro; Bustamante, Javier; Funes, Martín

    1995-01-01

    We studied the breeding performance of a Grey Eagle-Buzzard (Geranoaetus melanoleucus) population in a region of northern Argentinian Patagonia where two different habitats occur; the mountains near the Andean cordiBera and the plains where shrub-steppes predominate. Mean eagle density was I pair/I 9 km2 (N = 44), with higher densities occuring in the plains (1 pair/13.2 km2. N — 17) than in the mountains (1 pair/22.7 km2. N = 27). We located four communal roosts, with ...

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

    Directory of Open Access Journals (Sweden)

    María Cecilia Melo

    2009-06-01

    to Heteroptera from Patagonia (Río Negro. Since the early 60's the aquatic Heteroptera have been studied by A.O. Bachmann and his students. Up to now there are 36 recorded species belonging to the families Corixidae, Notonectidae, Belostomatidae, Gelastocoridae, Naucoridae, and Nepidae (Nepomorpha; Hydrometridae, Veliidae, and Mesoveliidae (Gerromorpha, and Saldidae (Leptopodomorpha. Most of these species extend their geographic distribution to northern Argentina except 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, P. paralia (Torres, P. angusta (Drake & Carvalho, P. sola (Drake & Carvalho, P. doeringi (Drake & Carvalho, and Saldula differata Drake & Carvalho (Saldidae, which are exclusive from Patagonia. The knowledge of the Patagonian aquatic and semiaquatic Heteroptera is accurate. According to the gathered data the state of conservation is acceptable; almost 40% of the species found in natural protected areas correspond to exclusive species from this region, representing almost the 40 % of the exclusive species from Patagonia.

  13. 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...

  14. Hydrographic data from the GEF Patagonia cruises

    Directory of Open Access Journals (Sweden)

    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.

  15. 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.

  16. Glacial Retreat in Chilean Patagonia

    Science.gov (United States)

    2002-01-01

    The San Quintin Glacier is the largest outflow glacier of the Northern Patagonian Ice Field in southern Chile. Its terminus is a piedmont lobe just short of the Golfo de Penas on the Pacific Ocean and just north of 47oS. Like many glaciers worldwide during the twentieth century, San Quintin appears to be losing mass and possibly retreating. Such a change is evident in these two photographs taken by astronauts only seven years apart. The first was taken by the crew of STS-068 in October1994 and the second by the Increment 4 crew of the International Space Station in February 2002. Even with the reversal of season and different lighting conditions of these two acquisitions, a loss of mass and change of structure, particularly in the lobe, are strikingly evident in these comparative photos. Glaciers are one of the special topics identified as scientific objectives for monitoring with photography from the International Space Station. Astronaut photography is a complimentary source of remote sensing data available for use with other sensor systems being used to monitor and study glaciers (see an ASTER image of the San Quintin Glacier). They also provide strong, visual context information on glacier environments and processes using a familiar medium, the camera. Images STS068-260-73 and ISS004-E-7267 were provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth.

  17. 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.

  18. Estudio comparado de la alimentación entre algunos predadores de alto nivel trófico de la comunidad marina del norte y centro de patagonia

    OpenAIRE

    Koen Alonso, M.

    1999-01-01

    The comparative analysis of the food habits between top predator allows the evaluation of how these species use the trophic resources. They also make possible the study of potentially competitive relationships and the role of these predators in the regulation and structure of the community. The marine community of northern and central Patagonia is structured on the tri-trophic system composed by the Argentine anchovy (Engraulis anchoita), the Argentine shortfin squid (Illex argent...

  19. 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

  20. 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

  1. 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

  2. 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.

  3. Proterozoic SCLM domains beneath Southern Patagonia

    Science.gov (United States)

    Mundl, Andrea; Ntaflos, Theodoros; Ackerman, Lukas; Bizimis, Michael; Bjerg, Ernesto

    2014-05-01

    Alkali basalt hosted mantle xenoliths from 3 different areas in South Patagonia were studied with regard to their petrography and chemical, as well as their Re-Os and Lu-Hf isotopic compositions. The Pali Aike Volcanic Field (PAVF) located in the very south of Patagonia comprises sample localities Salsa, El Ruido and Potrok Aike. About 300 km north, in the western part of Patagonia, samples were collected at Tres Lagos and further north-east, within and at the edge of the Deseado massif, are sample localities Gobernador Gregores and Don Camilo, respectively. The collected sample suite comprises sp-lherzolites, sp-harzburgites, one sp-dunite and exclusively within PAVF also sp-gt-lherzolites and sp-gt-harzburgites. Textures are mostly protogranular with very few samples showing weak foliation. Whole rock Al2O3 and CaO contents range from 0.63 to 3.54 wt.% and 0.24 to 3.44 wt.%, respectively and exhibit a linear correlation with MgO ranging from 39.2 to 49 wt.%. The more refractory peridotites are represented by samples from the PAVF while samples from the Deseado massif are generally more fertile. Indications for the formation age of SCLM domains can be provided using the Re-Os isotopic system. A suite of 24 modally unmetasomatised sp-lherzolites and sp-harzburgites analyzed for Re-Os isotopic composition reveals Neo- to Paleoproterozoic rhenium depletion ages. Don Camilo and Gobernador Gregores lherzolites indicate a SCLM formation in Mesoproterozoic times (0.9 to 1.3 Ga). Tres Lagos harzburgites reveal slightly older formation ages with a max. TRD of 1.7 Ga. Samples from within the PAVF vary more strongly in 187Os/188Os ratios with Neo- to late Paleoproterozoic TRDs. 3 refractory samples indicate an at least 2.4 Ga old formation age of the SCLM domain underneath PAVF. Hf isotopic data combined with the information obtained from Os isotopic analyses provide new information on potential metasomatic overprints and their probable timing. Negative to low positive

  4. 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...

  5. 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...

  6. 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

  7. Luminescence dating of glacial advances at Lago Buenos Aires (∼46 °S), Patagonia

    Science.gov (United States)

    Smedley, R. K.; Glasser, N. F.; Duller, G. A. T.

    2016-02-01

    Understanding the timing of past glacial advances in Patagonia is of global climatic importance because of the insight this can provide into the influence on glacier behaviour of changes in temperature and precipitation related to the Southern Westerlies. In this paper we present new luminescence ages determined using single grains of K-feldspar from proglacial outwash sediments that were deposited by the Patagonian Ice Sheet around Lago Buenos Aires (∼46 °S), east of the contemporary Northern Patagonian Icefield. The new luminescence ages indicate that major outwash accumulations formed around ∼110 ± 20 ka to 140 ± 20 ka and that these correspond to the Moreno I and II moraine ridges, which were previously dated using cosmogenic isotope dating to 150 ± 30 ka. Luminescence dating at Lago Buenos Aires has also identified outwash sediments that were deposited during glacial advances ∼30.8 ± 5.7 ka and ∼34.0 ± 6.1 ka (MIS 3) that are not recorded in the moraine record. Younger outwash accumulations were then deposited between ∼14.7 ± 2.1 and 26.2 ± 1.6 ka which correspond to the Fenix I - V moraine ridges. The combined chronology suggests that glacial advances occurred ∼110 ± 20 ka to 150 ± 30 ka (MIS 6), ∼30.8 ± 5.7 ka to ∼34.0 ± 6.1 ka (MIS 3), and ∼14.7 ± 2.1 to 26.2 ± 1.6 ka (MIS 2) at Lago Buenos Aires. Overall luminescence dating using single grains of K-feldspar has excellent potential to contribute towards the ever-increasing geochronological dataset constraining the timings of glacial advances in Patagonia.

  8. 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 ...

  9. 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....

  10. Geologic reconnaissance of Lautaro Volcano, Chilean Patagonia

    Directory of Open Access Journals (Sweden)

    Akihisa Motoki

    2006-01-01

    Full Text Available Lautaro is the volcano closest to the Chile Triple Junction in the Andean Austral Volcanic Zone. The volcanic edifice of 3,607 m a.s.l. stands out on the north-western part of the plateau of the South Patagonian Ice Field. The volcano basement is composed of low-grade meta-pelites that are cut by tabular intrusive bodies of hornblende-biotite granite. The volcano is almost completely covered by ice and the study was performed on volcanic detritus present in terminal moraines of the Lautaro Glacier and the tephra on the surface of the O'Higgins Glacier. The terminal moraines of Lautaro Glacier contain fragments of light grey dacite rich in plagioclase and hornblende phenocrysts. Some dacite blocks show prismatic jointing, suggesting an origin of hot emplacement and subsequent rapid cooling, possibly resulted from collapse of a steep lava front. Some samples have glassy groundmass and rhyolite-like flow texture, with presence of mafic inclusions and bread crust bomb texture. The surface of the O'Higgins Glacier is covered by lapilli-size pumice fallout deposit. There are many dirt cones covered by volcanic ash composed of pumice fragments, volcanic glass, quartz, plagioclase, biotite, hornblende, and orthopyroxene. The ash and pumice are similar in chemical composition, both indicating an adakitic signature. At least three layers of fallout deposits have been recognised in parts of the surface of the glacier, which may correspond to the latest known eruptionsReconocimiento geológico del volcán Lautaro, Patagonia chilena. El volcán Lautaro es el más próximo al Punto Triple de la dorsal de Chile en la Zona Volcánica Austral de los Andes. El edificio volcánico de 3.607 m s.n.m. se destaca como el punto más alto en la parte noroeste del plateau del Campo de Hielo Patagónico Sur. El basamento del volcán está compuesto por metapelitas de bajo grado metamórfico que están atravesadas por cuerpos tabulares constituidos por granitos de

  11. 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

  12. Scale-dependent analysis of an otter-crustacean system in Argentinean Patagonia

    Science.gov (United States)

    Cassini, Marcelo H.; Fasola, Laura; Chehébar, Claudio; MacDonald, David W.

    2009-05-01

    The Southern river otter or ‘huillin’, Lontra provocax, is an endangered species endemic of the Andean Patagonian region of Argentina and Chile. It feeds almost exclusively on the genera of macro-crustacea: Aegla and Sammastacus. The aim of this study was to analyse the role of food availability on the huillin’s distribution using a scale-dependent analysis of crustacean and otter distributions. We compared the distributions of otters and macro-crustaceans along a north-south regional gradient, between river basins of northern Patagonia, in an altitudinal gradient within a river basin, and between habitat types within a lake. We investigated the distribution of otters by sign surveys along lake shores, river banks and marine coasts, and of crustaceans using surveys in the water, undigested remains in mink ( Mustela vison) scats, presence of external skeletons at the waterside and through interviews with local people. Our results show that there were heterogeneities in the distributions of macro-crustaceans at four scales and these were generally reflected in the distributions of freshwater otters. We conclude that the main factor limiting the distributions of L. provocax in freshwater environments is the availability of macro-crustaceans. This paper shows how scale-dependent type analyses of population distribution serves as a method for identifying key environmental factors for species for which the use of long-term demographies is unfeasible.

  13. 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

  14. 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...

  15. 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.

  16. 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

  17. The origin of pyroxene megacrysts in alkali basalts from Patagonia, Argentina

    Science.gov (United States)

    Ntaflos, Theo; Bjerg, Ernesto; Gregoire, Michel

    2015-04-01

    Clinopyroxene and othopyroxene megacrysts have been brought to the surface together with mantle xenoliths by Neogene and Quaternary alkali basalts from the back-arc environment in Patagonia. The collected megacrysts are from Pali Aike Volcanic Field (El Ruido, maar) and the Gobernador Gregores cinder cone in southern Patagonia, and from the Laguna Fria outcrop in northern Patagonia. The most frequent pyroxene megacrysts are augites (twelve samples), one diopside and two enstatites. Enstatites were found in El Ruido and Laguna Fria. The augites are magnesian rich with MG# that vary from 73.1 to 75.3 in Gobernador Gregores, fairly constant at 76.6 in El Ruido and from 74.0 to 78.6 in Laguna Fria. The MG# of diopside is 91.1 and the two enstatites, one from Gobernador Gregores and the other from Laguna Fria, have MG#s 78.3 and 82.5 respectively. The Na2O and TiO2 contents in augites vary from 0.99 to 2.06 wt% and from 0.69 to 1.86 wt% repectively. Systematically, the Gobernador Gregores augites have the highest TiO2 and Na2O contents. The primitive mantle normalized REE abundances have concave upwards patterns. While the Gobernador Gregores augites have (La/Y)N ratios that vary from 2.4 to 3.8, the El Ruido and Laguna Fria augites have ratios that vary from 0.91 to 1.74. The enstatites from both localities have similar MREE but they differ markedly in their LREE (in GG LaN=0.04xPM and in El Ruido LAN=0.14) and in their HREE (in Gobernador Gregores YbN=0.25 and in El Ruido YBN=0.6). The AL IV/AL VI in all augites is high and vary from 0.75 to1.07 suggesting that they have been formed at - more than 30 km depth. The calculated minimum equilibrium temperatures vary between 1260 to 1320°C. Pressure estimates for augites, with exception of the El Ruido augites with a pressure of 1.65 GP, vary between 1.27 and 1.47 GPa. Especially the pressure estimates from Gobernador Gregores megacrysts vary within a small interval from 1.29 to 1.36 GPa indicating an isobaric

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

    Directory of Open Access Journals (Sweden)

    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

  19. MIGRACIÓN Y MOVILIDAD MAPUCHE A LA PATAGONIA ARGENTINA MAPUCHE MIGRATION AND MOBILITY TO ARGENTINIAN PATAGONIA

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    HANS GUNDERMANN

    2009-07-01

    Full Text Available El artículo presenta antecedentes acerca de la migración y movilidad campesina y mapuche desde las regiones de La Araucanía, Los Ríos y Los Lagos a la Patagonia argentina, especialmente al Neuquén y Río Negro, durante la segunda mitad del siglo XX, como parte de un proceso mucho más amplio de redistribución espacial que incluye el centro de Chile, Magallanes y la Patagonia trasandina. Se describen sus características 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 persistencia y transformación 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 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 persistence and transformation 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 its rural, urban and semi urban components.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. 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

    Tierra del Fuego. The samples, composed of adult male and female individuals, were arranged into four geographic groups corresponding to 5-degree wide latitudinal strips beginning at 40° South. Ten metric variables were measured on four bones (humerus, radius, femur and tibia. On the basis of femur maximum length and the brachial and crural indexes, several intra and intergroup statistical comparisons using one-way, two-way ANOVA and LSD were performed. The results obtained suggest that there is an intelligible pattern of geographic variation in the postcranial skeleton which can be explained by the convergence of different factors and processes, such as a climatic adaptation and low- to medium-range migratory movements (central and southern Patagonia and Tierra del Fuego; b medium- to long-range migration (northern Patagonia; and c insularity (Tierra del Fuego.

  5. Echoes of a distant time: effects of historical processes on contemporary genetic patterns in Galaxias platei in Patagonia.

    Science.gov (United States)

    Vera-Escalona, Iván; Habit, Evelyn; Ruzzante, Daniel E

    2015-08-01

    Interpreting the genetic structure of a metapopulation as the outcome of gene flow over a variety of timescales is essential for the proper understanding of how changes in landscape affect biological connectivity. Here we contrast historical and contemporary connectivity in two metapopulations of the freshwater fish Galaxias platei in northern and southernmost Patagonia where paleolakes existed during the Holocene and Pleistocene, respectively. Contemporary gene flow was mostly high and asymmetrical in the northern system while extremely reduced in the southernmost system. Historical migration patterns were high and symmetric in the northern system and high and largely asymmetric in the southern system. Both systems showed a moderate structure with a clear pattern of isolation by distance (IBD). Effective population sizes were smaller in populations with low contemporary gene flow. An approximate Bayesian computation (ABC) approach suggests a late Holocene colonization of the lakes in the northern system and recent divergence of the populations from refugial populations from east and west of the Andes. For the southern system, the ABC approach reveals that some of the extant G. platei populations most likely derive from an ancestral population inhabiting a large Pleistocene paleolake while the rest derive from a higher-altitude lake. Our results suggest that neither historical nor contemporary processes individually fully explain the observed structure and geneflow patterns and both are necessary for a proper understanding of the factors that affect diversity and its distribution. Our study highlights the importance of a temporal perspective on connectivity to analyse the diversity of spatially complex metapopulations. PMID:26147523

  6. 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.

  7. 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 ...

  8. 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

  9. 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...

  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. Tracing of mercury sources in Nahuel Huapi National Park, Patagonia, Argentina, using lichens as atmospheric bioindicators

    International Nuclear Information System (INIS)

    Full text: Usnea sp lichens were analysed in order to asses atmospheric sources of mercury in Nahuel Huapi National Park, Northern Patagonia, Argentina. Previous studies had shown that mercury contents in sediment and biota are high considering that within, or nearby, the region of study no relevant industrial or extensive agriculture activities exist. Pooled samples, made of at least 10 individuals, were analysed by Instrumental Neutron Activation Analysis. Sampling sites were defined following the steep precipitation gradient of the region, that ranges from 3000 mm.y-1 in the Western part of the park, to 500 mm.y-1 in the Eastern. Lithophile elements, associated with particulate matter entrapped by the lichen thalli, were identified, but mercury was not among these elements. Mercury contents range from (0.0558 ± 0.0083) to (1.38 ± 0.18) μg.g-1. The analysis of mercury contents determined in foliose lichens sampled from urban and periurban sites of Bariloche city, single relevant human settlement in the park, and from undisturbed regions, showed higher mercury contents in Bariloche air than in the surroundings. Transplanted thalli of fruticose Protousnea magellanica from undisturbed zones to urban sites confirmed this conclusion. 137Cs cumulative fluxes in the region were also determined from inventories of lake core sediments sampled nearby lichens sampling sites. Global transport followed by wet deposition is a potential source of mercury, and 137Cs is an anthropogenic isotope that can reach the Nahuel Huapi National Park only by atmospheric transport, stratospheric or tropospheric. Usnea sp mercury contents do not correlate with 137Cs cumulative fluxes along the precipitation gradient, leading to the conclusion that global transport and wet deposition is not the main mercury source in Nahuel Huapi National Park, and the analysis of the results suggests that more than one source are combined to impact the whole park area. (author)

  12. 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

  13. 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

  14. 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...

  15. Forest Typification to Characterize the Structure and Composition of Old-growth Evergreen Forests on Chiloe Island, North Patagonia (Chile

    Directory of Open Access Journals (Sweden)

    Jan R. Bannister

    2013-11-01

    Full Text Available The Evergreen forest type develops along the Valdivian and North-Patagonian phytogeographical regions of the south-central part of Chile (38° S–46° S. These evergreen forests have been scarcely studied south of 43° S, where there is still a large area made up of old-growth forests. Silvicultural proposals for the Evergreen forest type have been based on northern Evergreen forests, so that the characterization of the structure and composition of southern Evergreen forests, e.g., their typification, would aid in the development of appropriate silvicultural proposals for these forests. Based on the tree composition of 46 sampled plots in old-growth forests in an area of >1000 ha in southern Chiloé Island (43° S, we used multivariate analyses to define forest groups and to compare these forests with other evergreen forests throughout the Archipelago of North-Patagonia. We determined that evergreen forests of southern Chiloé correspond to the North-Patagonian temperate rainforests that are characterized by few tree species of different shade tolerance growing on fragile soils. We discuss the convenience of developing continuous cover forest management for these forests, rather than selective cuts or even-aged management that is proposed in the current legislation. This study is a contribution to forest classification for both ecologically- and forestry-oriented purposes.

  16. 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.

  17. Trophic ecology of Mustelus schmitti (Springer, 1939) in a nursery area of northern Patagonia

    Science.gov (United States)

    Molina, Juan Manuel; Cazorla, Andrea López

    2011-05-01

    Mustelus schmitti is an endangered endemic shark of the southwest Atlantic, and an important economical resource in Argentina, Brazil and Uruguay. The objective of this study was to describe the trophic ecology of M. schmitti in Anegada Bay, its feeding strategy and diet composition, along with the possible dietary shifts, due to season, sex, ontogeny and the different geographical features of the bay. Our results show that M. schmitti is a carnivorous opportunistic predator, feeding on a variety of benthic invertebrates. The diet presented seasonal and ontogenetic variations, while no differences in diet composition were observed between sexes or the different sampling sites. This species behave as a generalize feeder, with a wide trophic spectrum and a diverse diet.

  18. 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.

  19. Biology of Myliobatis goodei (Springer, 1939), a widely distributed eagle ray, caught in northern Patagonia

    Science.gov (United States)

    Molina, Juan Manuel; Lopez Cazorla, Andrea

    2015-01-01

    Chondrichthyans play an important role in structuring marine communities. Myliobatis goodie is an eagle ray reported from South Carolina in the USA (35°N) to Santa Cuz, Argentina (44°S), however little is known about this species, which is considered data deficient by the IUCN. In order to create adequate management strategies for this species, biological information is sorely needed. The objective of this study was to describe the biology of the population of M. goodei and its relationships with season, sex and the geographic features of Anegada Bay, Argentina (from 39.96°S to 40.60°S and from 62.10°W to 62.46°W) in 2008. Specifically, the population structure of M. goodie was studied by sex, seasons and sites, its food habits by seasons and sites, and the reproductive biology by seasons and sex. The results show that M. goodei exhibits seasonal migrations. Young-of-the-year remain in the bay all year long, while adults enter during spring and summer. Juveniles in spring are likely to become first-time mating individuals that migrate into open sea at the end of summer. These individuals would return to give birth for the first time and mate for the second time during the next year at summer. Anegada Bay would then be a mating and nursery area for the species. M. goodei behave as a generalist feeder with a uniform diet composed mainly of bivalves. Seasonal differences in the diet found arise from differences in prey diversity between summer and spring. Spatial differences, however, arise from the different abundances of caprellids and bivalves. Trophic level was 3.2 and it constitutes the first reference for this species, characterizing it as a secondary consumer.

  20. Reconstructing streamflow variation of the Baker River from tree-rings in Northern Patagonia since 1765

    Science.gov (United States)

    Lara, Antonio; Bahamondez, Alejandra; González-Reyes, Alvaro; Muñoz, Ariel A.; Cuq, Emilio; Ruiz-Gómez, Carolina

    2015-10-01

    The understanding of the long-term variation of large rivers streamflow with a high economic and social relevance is necessary in order to improve the planning and management of water resources in different regions of the world. The Baker River has the highest mean discharge of those draining both slopes of the Andes South of 20°S and it is among the six rivers with the highest mean streamflow in the Pacific domain of South America (1100 m3 s-1 at its outlet). It drains an international basin of 29,000 km2 shared by Chile and Argentina and has a high ecologic and economic value including conservation, tourism, recreational fishing, and projected hydropower. This study reconstructs the austral summer - early fall (January-April) streamflow for the Baker River from Nothofagus pumilio tree-rings for the period 1765-2004. Summer streamflow represents 45.2% of the annual discharge. The regression model for the period (1961-2004) explains 54% of the variance of the Baker River streamflow (R2adj = 0.54). The most significant temporal pattern in the record is the sustained decline since the 1980s (τ = -0.633, p = 1.0144 ∗ 10-5 for the 1985-2004 period), which is unprecedented since 1765. The Correlation of the Baker streamflow with the November-April observed Southern Annular Mode (SAM) is significant (1961-2004, r = -0.55, p River documented here for the 1980-2004 period is consistent with precipitation decrease associated with the SAM. Conversely, other studies have reported an increase of summer streamflow for a portion of the Baker River for the 1994-2008 period, explained by ice melt associated with temperature increase and glacier retreat and thinning. Future research should consider the development of new tree-ring reconstructions to increase the geographic range and to cover the last 1000 or more years using long-lived species (e.g. Fitzroya cupressoides and Pilgerodendron uviferum). Expanding the network and quality of instrumental weather, streamflow and other monitoring stations as well as the study and modeling of the complex hydrological processes in the Baker basin are necessary. This should be the basis for planning, policy design and decision making regarding water resources in the Baker basin.

  1. Reconstructing streamflow variation of the Baker River from tree-rings in Northern Patagonia since 1765

    Science.gov (United States)

    Lara, Antonio; Bahamondez, Alejandra; González-Reyes, Alvaro; Muñoz, Ariel A.; Cuq, Emilio; Ruiz-Gómez, Carolina

    2015-10-01

    The understanding of the long-term variation of large rivers streamflow with a high economic and social relevance is necessary in order to improve the planning and management of water resources in different regions of the world. The Baker River has the highest mean discharge of those draining both slopes of the Andes South of 20°S and it is among the six rivers with the highest mean streamflow in the Pacific domain of South America (1100 m3 s-1 at its outlet). It drains an international basin of 29,000 km2 shared by Chile and Argentina and has a high ecologic and economic value including conservation, tourism, recreational fishing, and projected hydropower. This study reconstructs the austral summer - early fall (January-April) streamflow for the Baker River from Nothofagus pumilio tree-rings for the period 1765-2004. Summer streamflow represents 45.2% of the annual discharge. The regression model for the period (1961-2004) explains 54% of the variance of the Baker River streamflow (R2adj = 0.54). The most significant temporal pattern in the record is the sustained decline since the 1980s (τ = -0.633, p = 1.0144 ∗ 10-5 for the 1985-2004 period), which is unprecedented since 1765. The Correlation of the Baker streamflow with the November-April observed Southern Annular Mode (SAM) is significant (1961-2004, r = -0.55, p network and quality of instrumental weather, streamflow and other monitoring stations as well as the study and modeling of the complex hydrological processes in the Baker basin are necessary. This should be the basis for planning, policy design and decision making regarding water resources in the Baker basin.

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

    OpenAIRE

    Alicia Forcone; José García; Gabriela Ayestarán

    2006-01-01

    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, Ranunculacea...

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

    Directory of Open Access Journals (Sweden)

    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

  4. 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

  5. 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

  6. Mineralogical association in the zone of argillic advanced alteration in a kaolin deposit of Patagonia Argentina

    International Nuclear Information System (INIS)

    This work is about the mineralogical and petrological relations of the para genetic association of advanced argillic zone in the kaolin deposit in Patagonia.This study allowed to establish the sequence of events that took place in the deposit as well as the conditions under which they were generated

  7. Ploidy levels and reproductive behaviour in invasive Hieracium pilosella in Patagonia

    Czech Academy of Sciences Publication Activity Database

    Krahulec, František; Krahulcová, Anna

    2011-01-01

    Roč. 11, - (2011), s. 25-31. ISSN 1619-0033 R&D Projects: GA ČR GA206/08/0890 Institutional research plan: CEZ:AV0Z60050516 Keywords : Patagonia * ploidy levels * hybridization Subject RIV: EF - Botanics

  8. 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.

  9. Sarcocystosis in wild red deer (Cervus elaphus) in Patagonia, Argentina.

    Science.gov (United States)

    Reissig, Elizabeth Chang; Moré, Gastón; Massone, Adriana; Uzal, Francisco A

    2016-05-01

    Sarcocystis spp. are protozoan parasites with a heteroxenous life cycle, which produce cysts in the muscle of herbivorous animals. In these animal species, sarcocystosis is frequently asymptomatic, although it may occur with high prevalence. Seven Sarcocystis spp. have been described in red deer (Cervus elephus). The aim of this study was to determine the prevalence of sarcocystosis, and to perform the morphological and molecular characterization of Sarcocystis spp. found in wild red deer of the Nahuel Huapi National Park (NHNP), Patagonia, Argentina. Full necropsies of 62 red deer killed by hunters in the NHNP and neighboring areas were performed. Samples of heart and skeletal muscle were examined histologically and selected samples were also examined by transmission electron microscopy (TEM), PCR and sequencing. Sarcocystis spp. thin walled cysts were detected in 62 % (38/62) of heart, and in 22 % (3/14) of skeletal muscle samples examined histologically. TEM revealed a smooth and thin cyst wall (≤1 μm), with scarce and separated ribbon-like protrusions. A total of three partial and one full 18S ribosomal RNA (rRNA) gene sequences were obtained, and showed the highest identity (≥99 %) with Sarcocystis taeniata, a species described in moose (Alces alces). The morphological and molecular results indicate that red deer in Argentina are frequently infected with S. taeniata, a species for which the definitive host is unknown. The present results also confirm that Sarcocystis spp. using cervids as intermediate host are not host-specific. Further studies are needed to improve the epidemiological knowledge of Sarcocystosis in red deer. PMID:26779923

  10. 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

  11. 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...

  12. 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

  13. 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

  14. 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 (data had reasonable model performance (NS ≈ 0.7). In spite of the better spatial resolution of the CFSR, the ability to simulate streamflow were not significantly different using either CFSR or ERA

  15. 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

  16. 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

  17. 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. PMID:26679700

  18. "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

  19. 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 ...

  20. 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...... need evaluation against an absolute chronology. The aim of this project is to investigate the applicability of OSL dating to sediments from southern Patagonia; in particular, we examine the dating potential of K-feldspar IRSL signals. Samples were collected from landforms interpreted as being deposited...... environmental ODs between 30 and 130% and mean residual doses between ∼30 and 80 Gy. Minimum age models are used to identify the part of the dose population that is most likely to have been well-bleached and results from these models are compared. The models give ages that are consistent with each other; this...

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

    Directory of Open Access Journals (Sweden)

    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.

  2. 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 ...

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

    OpenAIRE

    Lozada Mariana; Ladio Ana H; Eyssartier Cecilia

    2008-01-01

    Abstract Background In the present study we have investigated the cultural transmission of two types of traditional plant knowledge in two communities of North-western Patagonia, Argentina. In the Pilcaniyeu community, we studied the transmission of traditional knowledge related to horticultural practices in home-gardens, greenhouses and gardens; while in the community of Cuyin Manzano, we studied wild plant gathering customs. Methods Ethnobotanical fieldwork was conducted by means of semi-st...

  4. 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

  5. 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...

  6. 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...

  7. Metasomatism in the lithospheric mantle beneath southern Patagonia, Argentina

    Science.gov (United States)

    Kolosova-Satlberger, Olesya; Ntaflos, Theodoros; Bjerg, Ernesto

    2015-04-01

    Mantle xenoliths from Gobernador Gregores, southern Patagonia are spinel- lherzolites, harzburgites and wehrlites. Composite xenoliths consisting of websterites, olivine-websterites and spinel- lherzolites or harzburgites are present as well. The lithospheric mantle beneath Gobernador Gregores region was affected by multiple modal metasomatic events as can be inferred by the presence of amphibole, phlogopite and apatite. The existence of amphibole as inclusion in clinopyroxene suggests dehydration reaction of peridotites, which previously experienced modal metasomatism. This textural evidence records the earliest detectable metasomatic event. A second distinct modal metasomatic event consists of disseminated up to 6 mm in diameter coarse grained amphiboles (100*mg# =89.9) which show breakdown reactions and pseudomorphic replacement by glass and fine grained second generation of olivine, clinopyroxene and spinel. The intensity of the breakdown reaction is variable. In most cases amphibole occurs as a relict within these pseudomorphs. However, melt pockets of up to 10 mm in diameter are abundant, irregular in shape and having the same minerals such as in the pseudomorphs, indicate clearly amphibole breakdown because remnants of it were found enclosed by second generation clinopyroxene. Similar breakdown reactions experienced the phlogopite in the samples where is present. The Phlogopite (100*mg# =88.6) breakdown produces the same mineral phases as the amphibole. The second generation minerals formed after breakdown of amphibole and phlogopite show minor differences in their composition. However, the chemical composition of glass varies considerably. The glasses formed after breakdown of amphibole and phlogopite have trachyandesitic and tephriphonolitic composition, respectively. Some harzburgites and composite xenoliths reveal another metasomatic event: peridotite, enriched in orthopyroxene (mainly orthopyroxenite veinlets, rare websterite), suggests interaction with

  8. Northern employment

    International Nuclear Information System (INIS)

    Hiring practices and policies and employment opportunities that were available in the Beaufort Sea and MacKenzie Delta project for local residents and for people from southern Canada were dealt with in this chapter. Depending on the source, Northern hiring was a mere token, or a genuine and successful effort on the part of the companies to involve the native population and to share with them the benefits of the project. The fact remains that opening up job opportunities for Northerners was not easily attained, and would never have been realized without the involvement of government and community organizations. Government also played a major role in developing policies and training regimes. By the end of exploration operations, the hiring of Northern residents in the oil and gas industry had become a requirement of drilling applications. Training programs were also created to ensure that Northern residents received the means necessary to take advantage of Northern employment opportunities

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

    Directory of Open Access Journals (Sweden)

    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.

  10. 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.

  11. High Holocene lake levels in eastern Patagonia (Argentina) as a result of persistent Atlantic rainfall (Invited)

    Science.gov (United States)

    Ariztegui, D.; Compagnucci, R.; Agosta, E. A.

    2013-12-01

    Today's precipitation in central Patagonia, Argentina, mostly follows the intensity of the Westerlies. However, the extraordinary persistence of daily easterly winds can trigger episodes of intense rainfall reflected as water level variations in Lago Cardiel, a closed lacustrine basin located at 49°S. Meteorological data from 11-20 March 2002 at nearby Gobernador Gregores station recorded a heavy rain spell of 50mm accounting for 30% of the mean annual rainfall (167mm/year). The synoptic situation during this interval shows rainfall produced by wet air mass advection from the Atlantic. The weather surface maps for these days display a cyclone incoming at 45°S to the west of western Patagonia together with a concomitant anticyclone to the southwest, while a cyclogenesis initiates in eastern Patagonia. This pressure dipole produced east-north-eastern winds at the lake latitude and a generalized drop in the Westerlies intensity almost across the entire Patagonia. This is shown in distant stations such as Bariloche(41.9°S) and Rio Gallegos (51.4°S) in northwestern and southeastern Patagonia, respectively, as well as in Chilean stations such as Balmaceda (45.9°S) and Chile Chico (46.9°S). Similar pressure anomalies along with changes in wind intensity and direction have been previously simulated for the Austral winter (JJA) during the middle Holocene (7.0 to 4.5 kcal yrs BP). Thus, weaker Westerlies along with a higher frequency of the dipole-type atmospheric circulation than at present increased the described easterly winds-triggered rainfall. This inference agrees with high lake levels in the Lago Cardiel record along with more negative - Atlantic type - oxygen isotopic composition of authigenic carbonates. An increase in the frequency of this climatic configuration during longer time intervals could further explain the extreme lake highstands reconstructed for the early Holocene, and the contemporaneous negative isotopic signature of the carbonates. It could

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Quaternary volcanic activity of Hudson and Lautaro volcanoes, Chilean Patagonia: New constraints from K-Ar ages

    Directory of Open Access Journals (Sweden)

    Yuji Orihashi

    2004-12-01

    Full Text Available Twenty-nine K-Ar ages for lavas and juvenile ejecta obtained from Hudson volcano in the southern end of the Southern Volcanic Zone and Lautaro volcano in the northern end of the Austral Volcanic Zone, which are separated by a 350 km-long volcanic gap near the Chile ridge subduction zone, were determined using unspiked method that has significant sensitivity for dating young rocks (Actividad volcánica cuaternaria de los volcanes Hudson y Lautaro, Patagonia chilena: nuevas edades K-Ar. Mediante el uso del método K-Ar 'unspiked', el cual tiene notable sensibilidad para datar rocas jóvenes (<0,1 Ma, se obtuvieron 29 edades radiométricas de lavas y piroclastos juveniles de los volcanes Hudson y Lautaro. Separados por un 'gap' volcánico de 350 km, cercano a la zona de subducción de la dorsal de Chile, estos volcanes se ubican en los extremos sur de los Andes del Sur y norte de los Andes Australes, respectivamente. Estos datos indican que el volcán Hudson ha tenido un tiempo de desarrollo notablemente largo desde hace 1 Ma hasta el presente. Está formado por una caldera bien conservada de aproximadamente 10 km de diámetro, la cual, se pensaba había sido formada por sólo un evento eruptivo, probablemente a los 6700 años AP. Sin embargo, nuestros resultados revelan que los flancos nororiental y suroriental del volcán se originaron durante épocas diferentes, siendo más antigua la formación de la estructura norte. Observaciones fotogeológicas indican la presencia de dos o, eventualmente, tres bordes de caldera. Estos antecedentes indican que el volcán Hudson tuvo una evolución más bien compleja consistente en la sobreimposición o anidamiento parcial de estructuras, más que la formación de una caldera simple. De acuerdo con los primeros resultados de los presentes autores, en el caso del volcán Lautaro, la actividad que comenzó hace aproximadamente 0,17 Ma continúa hasta el presente. Aunque es un volcán relativamente grande

  14. Descripción de posibles híbridos naturales entre Nothofagus pumilio y N. antarctica en Patagonia Sur (Argentina) Description of possible natural hybrids between Nothofagus pumilio and N. antarctica at South Patagonia (Argentina)

    OpenAIRE

    Sarah Lilian Burns; Juan Manuel Cellini; María Vanessa Lencinas; Guillermo José Martínez Pastur; Stella Maris Rivera

    2010-01-01

    El género Nothofagus comprende alrededor de 35 especies nativas del Hemisferio Sur. En la Patagonia se han citado numerosos ejemplos de híbridos naturales entre varias especies de Nothofagus. El objetivo del presente trabajo fue analizar y describir la evidencia de la existencia de posibles híbridos naturales entre Nothofagus pumilio y N. antarctica en Patagonia Sur, mediante el estudio de caracteres morfológicos foliares. Se trabajó con 20 posibles híbridos recolectados en una zona de transi...

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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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

  17. Migración y movilidad mapuche entre Araucanía y nor Patagonia

    Directory of Open Access Journals (Sweden)

    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.

  18. 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 % = ...

  19. Pensando un museo de informática en la Patagonia austral

    OpenAIRE

    Sofía, Osiris; Hammar, Victoria

    2014-01-01

    Los avances en informática son tan vertiginosos y constantes que en muy poco tiempo el equipamiento utilizado entra en rápida obsolescencia. Existen numerosas tecnologías que han estado en uso hasta hace pocos años, pero que las nuevas generaciones no conocen e incluso no han oído nombrar (cintas, tarjetas perforadas, etc.). Por esto, la Universidad Nacional de la Patagonia Austral creó el Museo de Informática: un espacio para salvaguardar los objetos informáticos y utilizarlos como recurs...

  20. De Patagonia a Budapest: caminos europeos de fósiles santacrucenses (1845-1956)

    OpenAIRE

    Vizcaíno, Sergio Fabián; Bargo, M. Susana

    2013-01-01

    A fines del siglo XIX y principios del XX, acicateados por los descubrimientos de los hermanos Ameghino, los paleontólogos evolucionistas de América del Norte y Europa posaron sus ojos en los mamíferos fósiles de Patagonia. Mientras los primeros organizaron expediciones, los europeos se valieron mayormente de otras formas comunes en la época para hacer colecciones de historia natural, como el intercambio y la compra. En el viejo continente, el devenir de los fósiles patagónicos no escapó a la...

  1. 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

  2. Nuevos exámenes de sedimentos arqueológicos en Patagonia

    OpenAIRE

    Fugassa, Martín H.; Martínez, P. A.; Guichón, Ricardo Aníbal; Centeno, Néstor Daniel

    2007-01-01

    Se informa sobre nuevos estudios paleobiológicos en sedimentos arqueológicos de Patagonia. Se analizaron sedimentos pertenecientes a la cintura pélvica de uno de los cuerpos hallados en el sitio Alero Mazquiarán, Chubut, Argentina (212±5 años AP). Durante el estudio paleoparasitológico de los sedimentos se observaron diversos restos de artrópodos. Éstos se colectaron y se examinaron bajo lupa. Asimismo, se realizó flotación para recuperar restos microscópicos registrándose numerosos ácaros de...

  3. 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 ...

  4. 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.

  5. 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.

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

    OpenAIRE

    Belén Alvaro; Verónica Trpin

    2013-01-01

    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 dispos...

  7. 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.

  8. 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

  9. 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

  10. Eocene plant diversity at Laguna del Hunco and Río Pichileufú, Patagonia, Argentina.

    Science.gov (United States)

    Wilf, Peter; Johnson, Kirk R; Cúneo, N Rubén; Smith, M Elliot; Singer, Bradley S; Gandolfo, Maria A

    2005-06-01

    The origins of South America's exceptional plant diversity are poorly known from the fossil record. We report on unbiased quantitative collections of fossil floras from Laguna del Hunco (LH) and Río Pichileufú (RP) in Patagonia, Argentina. These sites represent a frost-free humid biome in South American middle latitudes of the globally warm Eocene. At LH, from 4,303 identified specimens, we recognize 186 species of plant organs and 152 species of leaves. Adjusted for sample size, the LH flora is more diverse than comparable Eocene floras known from other continents. The RP flora shares several taxa with LH and appears to be as rich, although sampling is preliminary. The two floras were previously considered coeval. However, (40)Ar/(39)Ar dating of three ash-fall tuff beds in close stratigraphic association with the RP flora indicates an age of 47.46+/-0.05 Ma, 4.5 million years younger than LH, for which one tuff is reanalyzed here as 51.91+/-0.22 Ma. Thus, diverse floral associations in Patagonia evolved by the Eocene, possibly in response to global warming, and were persistent and areally extensive. This suggests extraordinary richness at low latitudes via the latitudinal diversity gradient, corroborated by published palynological data from the Eocene of Colombia. PMID:15937744

  11. 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.

  12. 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)

  13. Anthropogenic mercury signals in lake sediments from southernmost Patagonia, Chile

    International Nuclear Information System (INIS)

    Atmospheric mercury fluxes to terrestrial and aquatic surfaces in the Northern Hemisphere have increased since the Industrial Revolution. However fluxes are not well characterized for the Southern Hemisphere, since environmental archives are comparatively scarce. Mercury records from 210Pb-dated sediment cores of three South Patagonian lakes were investigated in order to reveal the influence of anthropogenic activities on atmospheric mercury deposition in remote lakes of the Southern Hemisphere. Comparison with indicators of organic matter sources (carbon and nitrogen/carbon ratios) and a conservative mineral soil element (zirconium) in the sediments revealed that soil erosion is an important process contributing mercury to these lakes and influenced variation in concentrations through time. However, at ∼ 1900 AD mercury accumulation increased independent from soil erosion and peaked from 1980 to 2000 AD. We attribute this to an increase in atmospheric mercury deposition in this remote region of the Southern Hemisphere. Mean flux ratios, which reflect the increase in modern mercury accumulation compared to pre-1850 AD, lie within a range of 1.4 to 2.4. These values indicate an increase in atmospheric mercury deposition slightly lower than predictions derived from global mercury models that suggest an increase in Hg deposition by a factor of 2 to 3. - Highlights: ► Hg concentrations and accumulation rates were determined in South Patagonian lake sediments. ► Soil erosion was shown to account significantly for short-term variations in Hg accumulation. ► Increased Hg accumulation since 1900 AD (factor of 1.4–2.4) is attributed to a rise in atmospheric Hg. ► Accumulation of anthropogenic Hg peaked between 1980 and 2000 AD (∼ 3 μg m−2 yr−1)

  14. Anthropogenic mercury signals in lake sediments from southernmost Patagonia, Chile

    Energy Technology Data Exchange (ETDEWEB)

    Hermanns, Yvonne-Marie, E-mail: y-m.hermanns@tu-bs.de; Biester, Harald, E-mail: h.biester@tu-bs.de

    2013-02-15

    Atmospheric mercury fluxes to terrestrial and aquatic surfaces in the Northern Hemisphere have increased since the Industrial Revolution. However fluxes are not well characterized for the Southern Hemisphere, since environmental archives are comparatively scarce. Mercury records from {sup 210}Pb-dated sediment cores of three South Patagonian lakes were investigated in order to reveal the influence of anthropogenic activities on atmospheric mercury deposition in remote lakes of the Southern Hemisphere. Comparison with indicators of organic matter sources (carbon and nitrogen/carbon ratios) and a conservative mineral soil element (zirconium) in the sediments revealed that soil erosion is an important process contributing mercury to these lakes and influenced variation in concentrations through time. However, at ∼ 1900 AD mercury accumulation increased independent from soil erosion and peaked from 1980 to 2000 AD. We attribute this to an increase in atmospheric mercury deposition in this remote region of the Southern Hemisphere. Mean flux ratios, which reflect the increase in modern mercury accumulation compared to pre-1850 AD, lie within a range of 1.4 to 2.4. These values indicate an increase in atmospheric mercury deposition slightly lower than predictions derived from global mercury models that suggest an increase in Hg deposition by a factor of 2 to 3. - Highlights: ► Hg concentrations and accumulation rates were determined in South Patagonian lake sediments. ► Soil erosion was shown to account significantly for short-term variations in Hg accumulation. ► Increased Hg accumulation since 1900 AD (factor of 1.4–2.4) is attributed to a rise in atmospheric Hg. ► Accumulation of anthropogenic Hg peaked between 1980 and 2000 AD (∼ 3 μg m{sup −2} yr{sup −1})

  15. Is the prominent ericoid mycorrhizal fungus Rhizoscyphus ericae absent in the Southern Hemisphere's Ericaceae? A case study on the diversity of root mycobionts in Gaultheria spp. from northwest Patagonia, Argentina.

    Science.gov (United States)

    Bruzone, M Clara; Fontenla, Sonia B; Vohník, Martin

    2015-01-01

    Ericaceae diversity hotspots are in the mountains of the Neotropics and Papua New Guinea, South Africa's fynbos and Southeast Asia but majority of references to their root mycobionts come from the Northern Hemisphere. Here, typical cultivable ericoid mycorrhizal (ErM) fungi comprise Rhizoscyphus ericae, Meliniomyces variabilis, and Oidiodendron maius. It is however unclear whether this is true also for the Southern Hemisphere. Our study focused on cultivable mycobionts from hair roots of Gaultheria mucronata and Gaultheria poeppigii (Ericaceae) from two natural forests in NW Patagonia, Argentina, differing in mycorrhizal preferences of their tree dominants. We detected 62 well-defined OTUs mostly belonging to Helotiales and Hypocreales; the most frequent were Phialocephala fortinii s. l., Pochonia suchlasporia, and Ilyonectria radicicola. Only one out of 257 isolates showed ITS nrDNA similarity to members of the R. ericae aggregate (REA) but was not conspecific with R. ericae, and only five isolates were conspecific with O. maius. Microscopic observations showed that the screened roots were frequently colonized in a manner differing from the pattern typically produced by R. ericae and O. maius. A re-synthesis experiment with selected isolates showed that only O. maius formed colonization resembling ericoid mycorrhiza. Amplification of root fungal DNA with REA-specific and Sebacinaceae-specific primers showed that REA mycobionts were present in some of the screened samples while Sebacinaceae were present in all samples. These results suggest that Gaultheria spp. from NW Patagonia form ericoid mycorrhizae predominantly with the difficult-to-cultivate Sebacinaceae while the incidence of REA is relatively low and may be masked by other most likely non-mycorrhizal cultivable mycobionts. PMID:24838300

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

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    Alicia S. SANGUINETTI

    2009-12-01

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

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

    OpenAIRE

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

    2016-01-01

    The fish processing operations in Patagonia produce large amounts of waste. The main fishery resource in Argentina is the Argentine hake (Merluccius hubbsi). The ports of the province of Chubut (the most important of which are Puerto Madryn, Rawson and Comodoro Rivadavia), together with Caleta Paula Port (province of Santa Cruz), in the Argentine Patagonia, capture more than 82,000 tons of hake annualy, 80% of which are of M. hubbsi, which is mostly converted into fillets. From this capture, ...

  18. Historical records of southern right whales (Eubalaena australis) of the province Río Negro, North Patagonia, Argentina (1991-2008)

    OpenAIRE

    Failla, Mauricio; Vermeulen, Els; Cammareri, Alejandro

    2008-01-01

    The increase of the southern right whale (SRW Eubalaena australis) population might rise questions about the reoccupation of previous sites. This report is a compilation of historical records of SRWs along the coast of the Río Negro province, Northeast Patagonia, to evaluate the tendency of their occurrence in the area over the past decade. A total of 308 records (425 whales) were collected over distinct coastal regions in Northeast Patagonia. The majority of sightings were concentrated be...

  19. Respuesta dietaria de tres rapaces frente a una presa introducida en Patagonia Dietary response of three raptor species to an introduced prey in Patagonia

    Directory of Open Access Journals (Sweden)

    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

  20. 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

  1. 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.

  2. Environmental changes in two lakes of Northern Patagonia (Chile): A 1000 yr reconstruction based on pollen and charcoal

    Science.gov (United States)

    Nicole, Vargas; Laura, Torres; Alberto, Araneda; Fabiola, Cruces; Fernando, Torrejón; Denisse, Alvarez; G, Bizama; Nathalie, Fagel; Roberto, Urrutia

    2010-05-01

    We aim to reconstruct the environmental changes experimented in Patagonian ecosystems during the last 1000 years. We analyze sediment cores from two lakes (Thompson and Burgos), located in Aysen Region, Southern Chile. The samples were obtained using a gravity corer and sampled at intervals of 1 cm to 30 cm depth and every 5 cm until the end of the core. Thompson lake sediment core was sampled every 5 cm. Age model is based on radiocarbon datings on bulk sediments and macroremains. In Burgos lake we evidence two main climatic changes. A wet period between 876-1444 AD is marked by the presence of Pteridophytes. A colder and dryer period is then evidenced by an increase of Berberis sp between 1444 and 1656 AD. From 1834 AD to Present the sediment record is mainly affected by human activities. High concentrations of carbon particles and a sharp change in pollen assemblage (increase of Poaceae, decrease of Nothofagus dombeyi-Type) are indicators of two large fire events. The lacustrine sediment of Thompson is characterized by a wetter period, between 874 - 1168 AD, with abundance of Pteridophytes. Then from 1168 AD to Present the environmental conditions of the watershed were characterized by lower ferns and fire events. Two major fires were evidenced between 1850 AD and Present. Like in Burgos they are marked by major changes in plant associations (sharp increase in Poaceae, drastic loss of Nothofagus dombeyi-Type). Wet periods identified in both lakes at the base of the sediment record could correspond to manifestations of a warm climate anomaly like the Medieval Warm Period. The dry and cold period, especially obvious in the Burgos record, could be associated to a cold climate anomaly. Finally the great changes in vegetation that occurred from the year ~ 1830 in the basin of the two lakes were directly related to human activities (forest cutting) developed during the ninetheenth and twentieth centuries. This research is funded by both Chilean and Belgian projects (Fondecyt project N° 1070508; WBI Wallonie-Chile cooperation project, FNRS and ULg fundings).

  3. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  5. 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.

  6. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Glacial, fluvial and volcanic landscape evolution in the Laguna Potrok Aike maar area, Southern Patagonia, Argentina

    Science.gov (United States)

    Coronato, Andrea; Ercolano, Bettina; Corbella, Hugo; Tiberi, Pedro

    2013-07-01

    We describe the Pleistocene evolution of the landscape in the Laguna Potrok Aike area in southern Patagonia, Argentina, based on a geomorphological survey. Basaltic eruptions generated tablelands and scoria cones between the Late Miocene and Middle Pleistocene, and phreatomagmatic eruptions produced maars during Middle and Late Pleistocene time. The first glaciations during the Early Pleistocene generated a gently undulating to flat landscape that was affected by cryogenic processes; they are documented but not dated. Outwash surfaces indicate that the Greatest Patagonian Glaciation was multi-phased. The eruption that produced Potrok Aike maar truncated terrace levels dating to a Middle Pleistocene glaciation. The abundance of maars dating to this time may be linked to large amounts of water associated with meltwater streams and permafrost. The landscape in the Potrok Aike area has changed little since the Middle Pleistocene and only minor modifications of landforms have occurred due to cryogenesis, moderate fluvial incision, mass wasting and eolian activity.

  9. 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...

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

    Science.gov (United States)

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

    2015-02-28

    We compared the carapace shape and thickness as well as the energy density of Ovalipes trimaculatus inhabiting areas comprising a gradient of marine pollution: high, moderate and undetected, in the Nuevo gulf (Patagonia Argentina). The carapace shape was evaluated by means of individual asymmetry scores (=fluctuating asymmetry) whereas the carapace thickness was assessed by measuring the carapace dry weight. The energy density was analyzed through its negative relationship with water content in muscle tissue. The individual asymmetry scores as well as the percentage of water content in muscle tissue were proportional to the marine pollution gradient, whereas the carapaces thickness did not differ among sampling sites. Our results are consistent with previous findings and demonstrate the direct effect of marine pollution on other taxa different from gastropods, cephalopods and polyplacophora and add to long-standing concerns about detrimental effects caused by marine pollution on the benthic community of the Nuevo gulf. PMID:25293645

  11. Bonitasaura salgadoi gen. et sp. nov.: a beaked sauropod from the Late Cretaceous of Patagonia

    Science.gov (United States)

    Apesteguía, Sebastián

    2004-10-01

    Ornithischian and theropod dinosaurs were morphologically diverse during the Cretaceous. In contrast, sauropods were relatively more conservative. The anatomy of Bonitasaura salgadoi, a new 9-m titanosaurian sauropod from Upper Cretaceous beds of Patagonia, suggests that sauropod anatomical diversity would have included unexpected items. Its unusual, rectangular lower jaw possesses narrow, anteriorly restricted teeth and shows evidence of a sharp keratinous sheath over the non-dentigerous region that probably worked to guillotine plant material. This discovery definitely demonstrates that titanosaurs acquired a mandibular configuration similar to that of some basal diplodocoids, as had already been suggested by the lower jaw of the controversial genus Antarctosaurus. This oral configuration, plus the beak-like structure and the skull shape, resemble some traits more commonly seen in Laurasian ornithischians, mostly unexpressed in southern continents. A high sauropod morphological diversity seems to be in agreement with the poorly represented ornithischian clades of the southern hemisphere.

  12. Chronological study of the pre-jurassic basement rocks of southern Patagonia

    International Nuclear Information System (INIS)

    Southern Patagonia east of the Andes was the site of extensive rhyolite volcanism during the Jurassic rifting of Gondwana and subsequent shallow marine basin formation during the Cretaceous. Thus exposures of pre-Jurassic basement are extremely sparse. Nevertheless, extraction of the maximum amount of information from these scattered outcrops of granite and metamorphic rocks is crucial to assessment of the Palaeozoic and earliest Mesozoic history and crustal structure of the Pacific margin of the supercontinent. In particular, the identification and possible correlation of early terrane accretion on this margin depends on comparison of pre-Jurassic igneous and metamorphic events with adjacent areas. This is a preliminary report on work now in progress to this end (au)

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

    Directory of Open Access Journals (Sweden)

    Mariano Donato

    2009-06-01

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

  14. 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.

  15. Radiocarbon chronology of the last glacial maximum and its termination in northwestern Patagonia

    Science.gov (United States)

    Moreno, Patricio I.; Denton, George H.; Moreno, Hugo; Lowell, Thomas V.; Putnam, Aaron E.; Kaplan, Michael R.

    2015-08-01

    We examine the timing and magnitude of the last glacial maximum (LGM) and the last glacial termination (LGT) in northwestern Patagonia, situated in the middle latitudes of South America. Our data indicate that the main phase of the LGT began with abrupt warm pulses at 17,800 and 17,100 cal yrs BP, accompanied by rapid establishment of evergreen temperate rainforests and extensive deglaciation of the Andes within 1000 years. This response shows that South American middle-latitude temperatures had approached average interglacial values by 16,800 cal yrs BP. The temperature rise in northwestern Patagonia coincides with the beginning of major warming and glacier recession in the Southern Alps of New Zealand at southern mid-latitudes on the opposite side of the Pacific Ocean. From this correspondence, the warming that began at 17,800 cal yrs BP appears to have been widespread in middle latitudes of the Southern Hemisphere, accounting for at least 75% of the total temperature recovery from the LGM to the Holocene. Moreover, this warming pulse is coeval with the first half of the Heinrich Stadial 1 (HS1) in the North Atlantic region. HS1 featured a decline of North Atlantic meridional overturning circulation, a southward shift of the westerly wind belt in both hemispheres and of the Intertropical Convergence Zone, as well as a weakening of the Asian monsoon. Along with the initiating trigger, identifying the mechanisms whereby these opposing climate signals in the two polar hemispheres interacted -whether through an oceanic or an atmospheric bipolar seesaw, or both- lies at the heart of understanding the LGT.

  16. Geochemical evidence of past earthquakes in sediments of the Reloncaví fjord (Chilean Patagonia) during the last ˜ 1000 years

    Science.gov (United States)

    Rebolledo, Lorena; Lange, Carina; Muñoz, Práxedes; Salamanca, Marco

    2014-05-01

    The Chilean fjords are excellent archives of paleoearthquakes, tsunamis and landslides (St-Onge et al., 2012 in Sedimentary Geology 243-244: 89-107). Here we report on new sedimentological and geochemical evidence of past earthquakes in sediments of the Reloncavi fjord, Northern Patagonia (41° S, 72° W), during the last ~1000 years. We recovered four sediment cores from the Reloncaví fjord (RH-5B, RH-5C, RH-6B, RH7B, water depth range = 90-260 m; core length range = 45-75 cm). Age models were based on 210Pb, AMS-14C and the first appearance of the diatom Rhizosolenia setigera cf. pungens in the fossil record as statigraphic marker. The cores span the last ~122 to 800 years of sedimentation with sedimentation rates ranging between 0.1 and 0.24 cm yr-1. The cores revealed evidence of turbidites associated with the historical earthquakes of 1960, 1837, 1737 and 1575 AD, and an earlier period for which there is no historical information, 1200-1400 AD. The turbidites exhibit a grading-up pattern with sand layers, and are characterized by a decrease in organic carbon and biogenic opal, an increase in the C/N molar ratio, negative values of δ13Corg(average -27),and an increase in the relative abundance of Paralia sulcata, a diatom associated with sandy environments, being the turbite layers mainly freshwater in origen. We suggest that these turbidite layers were triggered by past earthquakes that produced movement of land from the cliff areas that surround the Reloncaví fjord. Funding: Project FONDECYT # 11110103 and COPAS Sur-Austral project PFB-31.

  17. 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

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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Rhizolith balls from the Lower Cretaceous of Patagonia: Just roots or the oldest evidence of insect agriculture?

    OpenAIRE

    Alonso-Zarza, Ana María; Genise, J.F.

    2010-01-01

    A new type of trace fossil from the Lower Cretaceous of Patagonia that may record the oldest evidence of insect agriculture is represented by biconvex, sub-spherical, carbonate balls composed of a dense mass of rhizoliths. The best preserved balls show an external wall, a tunnel entrance, and vertical, large rhizoliths crossing from top to base, from which a mass of smaller rhizoliths arise. In some cases there is a pelletal surface texture in internal layers of the wall. Some spe...

  1. 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...

  2. 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.

  3. 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

  4. 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

  5. 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

  6. OSTEOMETRÍA DE VICUGNA VICUGNA MOLINA, 1782 EN EL PLEISTOCENO FINAL DE PATAGONIA MERIDIONAL CHILENA: IMPLICANCIAS PALEOECOLÓGICAS Y BIOGEOGRÁFICAS / Osteometry of Vicugna vicugna Molina, 1782 in the late Pleistocene of southern chilean Patagonia

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    Rafael Labarca Encina

    2009-12-01

    Full Text Available  Se presenta un análisis osteométrico uni y multivariado con los materiales fósiles -principalmente huesos cortos y falanges- de Vicugna sp. del yacimiento Cueva Lago Sofía 4 (13500 – 11000 AP, ubicado en la provincia de Última Esperanza (Región de Magallanes, Chile. Los resultados indican que los elementos analizados poseen un tamaño compatible con los registrados para Vicugna vicugna, no superando en ningún caso a los especímenes conocidos para Vicugna gracilis del Pleistoceno de la región Pampeana. Esto confirma la información morfológica y de ADN antiguo que indicaba la presencia de Vicugna vicugna en la Patagonia meridional chilena. Se discuten los resultados en términos taxonómicos, biogeográficos y paleoecológicos sugiriendo que la presencia de este taxón fuera de su rango actual de distribución se debió a las condiciones ambientales compartidas entre la Puna y Patagonia austral durante la transición Pleistoceno-Holoceno. La extinción de V. vicugna se habría debido al impacto de los cambios climáticos ocurridos al inicio del Holoceno producto de su dieta pastadora y etología no migratoria y territorial, a lo que se habría sumado una caza por parte de depredadores humanos y no humanos.Palabras clave: género Vicugna, osteometría, Pleistoceno, Patagonia AbstractThis contribution presents the results of single and multi-variable osteometric analyses performed on a sample of short bones and phalanxes assigned to Vicugna sp. from Lago Sofía Cave 4 site (13500 – 11000 BP, Región de Magallanes, Chile. The elements analyzed show a similar size to the reference collections for Vicugna vicugna, and do not exceed the metrics for the pampean pleistocenic specimens of Vicugna gracilis. This confirms the morphological and ancient DNA data that indicated the presence of vicuña in southern Chilean Patagonia. The taxonomic, biogeographic and palaeoecologic discussion of these results, suggests that the presence of this

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

    OpenAIRE

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

    2008-01-01

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

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

    OpenAIRE

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

    2008-01-01

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

  9. 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...

  10. 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.

  11. Nuisance ecology: do scavenging condors exact foraging costs on pumas in Patagonia?

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    L Mark Elbroch

    Full Text Available Predation risk describes the energetic cost an animal suffers when making a trade off between maximizing energy intake and minimizing threats to its survival. We tested whether Andean condors (Vultur gryphus influenced the foraging behaviors of a top predator in Patagonia, the puma (Puma concolor, in ways comparable to direct risks of predation for prey to address three questions: 1 Do condors exact a foraging cost on pumas?; 2 If so, do pumas exhibit behaviors indicative of these risks?; and 3 Do pumas display predictable behaviors associated with prey species foraging in risky environments? Using GPS location data, we located 433 kill sites of 9 pumas and quantified their kill rates. Based upon time pumas spent at a carcass, we quantified handling time. Pumas abandoned >10% of edible meat at 133 of 266 large carcasses after a single night, and did so most often in open grasslands where their carcasses were easily detected by condors. Our data suggested that condors exacted foraging costs on pumas by significantly decreasing puma handling times at carcasses, and that pumas increased their kill rates by 50% relative to those reported for North America to compensate for these losses. Finally, we determined that the relative risks of detection and associated harassment by condors, rather than prey densities, explained puma "giving up times" (GUTs across structurally variable risk classes in the study area, and that, like many prey species, pumas disproportionately hunted in high-risk, high-resource reward areas.

  12. Origin of melt pockets in mantle xenoliths from southern Patagonia, Argentina

    Science.gov (United States)

    Aliani, Paola; Ntaflos, Theodoros; Bjerg, Ernesto

    2009-12-01

    Peridotite mantle xenoliths collected north of Gobernador Gregores, Patagonia, affected by cryptic and modal metasomatism bear melt pockets of unusually large size. Melt pockets consist of second generation olivine (ol2), clinopyroxene (cpx2) and spinel (sp2) ± relict amphibole (amph) immersed in a yellowish vesicular glass matrix. Amphibole breakdown was responsible for melt pocket generation as suggested by textural evidence and proved by consistent mass-balance calculations: amph → cpx2 + ol2 + sp2 + melt. Composition of calculated amphibole in amphibole-free melt pockets is very similar to that measured in amphibole-bearing melt pockets from the same xenolith, i.e. amphibole was consumed in the melt pocket generation process. In melt pockets devoid of relict amphibole, mass-balance calculations show remarkable differences between the calculated amphibole and the measured amphibole compositions in melt pockets from the same xenolith. The participation of minor proportions of a consumed reactant phase could be a reasonable explanation. In some samples the calculated phase proportion of glass is in excess compared to modal estimations based on backscattered electron images, probably because a portion of the generated melt was able to migrate out of the melt pockets. Compositional inhomogeneity of cpx2 and variable Ti Kd in cpx2 vs. glass in the same melt pocket reflect fast nucleation and growth and disequilibrium crystallisation, respectively. This and the difference between forsterite content in calculated equilibrium olivine and second generation olivine, suggest that mineral equilibrium was inhibited by rapid quenching of melt pockets.

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

    Directory of Open Access Journals (Sweden)

    L. Ghermandi

    2010-05-01

    Full Text Available Fire is a critical disturbance in the structuring and functioning of most Mediterranean ecosystems. In northwestern Patagonia, vegetation patterns are strongly influenced by fire and environmental heterogeneity. Dendroecology, together with satellite imagery and GIS, have been demonstrated to be useful tools in studies that relate to fire effects with patches, patterns and species dynamics at landscape scale. Such studies can be approached from landscape ecology, which has evolved in the last years supported by the development of remote sensing and GIS technologies. This study evaluates the spatial dynamic of F. imbricata in response to fire using remote sensing, GIS and dendrochronology techniques, at landscape scale. Two sites were evaluated and one of them was affected by fire in the year 1999. The digital processing images (using the NBR spectral index and the dendroecological analysis verified this. A fire, occurring in 1978, was also detected by the analysis of F. imbricata growth rings. The relation between F. imbricata shrubland dynamics and spatial configuration with fire, land topography and hydrography was established in the study area.

  14. 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)

  15. 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

  16. Microbial Life in a Fjord: Metagenomic Analysis of a Microbial Mat in Chilean Patagonia

    Science.gov (United States)

    Ugalde, Juan A.; Gallardo, Maria J.; Belmar, Camila; Muñoz, Práxedes; Ruiz-Tagle, Nathaly; Ferrada-Fuentes, Sandra; Espinoza, Carola; Allen, Eric E.; Gallardo, Victor A.

    2013-01-01

    The current study describes the taxonomic and functional composition of metagenomic sequences obtained from a filamentous microbial mat isolated from the Comau fjord, located in the northernmost part of the Chilean Patagonia. The taxonomic composition of the microbial community showed a high proportion of members of the Gammaproteobacteria, including a high number of sequences that were recruited to the genomes of Moritella marina MP-1 and Colwelliapsycherythraea 34H, suggesting the presence of populations related to these two psychrophilic bacterial species. Functional analysis of the community indicated a high proportion of genes coding for the transport and metabolism of amino acids, as well as in energy production. Among the energy production functions, we found protein-coding genes for sulfate and nitrate reduction, both processes associated with Gammaproteobacteria-related sequences. This report provides the first examination of the taxonomic composition and genetic diversity associated with these conspicuous microbial mat communities and provides a framework for future microbial studies in the Comau fjord. PMID:24015199

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

    Science.gov (United States)

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

    2007-02-01

    The occurrence of culturable yeasts in glacial meltwater from the Frías, Castaño Overo and Río Manso glaciers, located on Mount Tronador in the Nahuel Huapi National Park (Northwestern Patagonia, Argentina) is presented. Subsurface water samples were filtered for colony counting and yeast isolation. The total yeast count ranged between 6 and 360 CFU L(-1). Physiologic and molecular methods were employed to identify 86 yeast isolates. In agreement with yeast diversity data from studies for Antarctic and Alpine glaciers, the genera Cryptococcus, Leucosporidiella, Dioszegia, Rhodotorula, Rhodosporidium, Mrakia, Sporobolomyces, Udeniomyces and Candida were found. Cryptococcus and Leucosporidiella accounted for 50% and 20% of the total number of strains, respectively. Among 21 identified yeast species, Cryptococcus sp. 1 and Leucosporidiella fragaria were the most frequent. The typically psychrophilic Mrakia yeast strain and three new yeast species, yet to be described, were also isolated. All yeast strains were able to grow at 5, 10, and 15 degrees C. Among yeast strains expressing extracellular enzymatic activity, higher proteolytic and lipolytic activities were obtained at 4 degrees C than at 20 degrees C. PMID:17313582

  18. 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.

  19. Investigation of the characteristics of sandstone type uranium deposits in the Patagonia Region: Recent advances

    International Nuclear Information System (INIS)

    In the years 1995 and 1996, additional 16,300 m of drilling was carried out in the Cerro Solo area, Province of Chubut, Patagonia Region. This led to the improvement of the resource estimate of the main orebodies, in tonnes of recoverable uranium at costs of up to $ 80/kg U to the following: reasonable assured resources: 2,200 t U; estimated additional resources (C.I): 900 t U. Additionally, the gathering of specific information gave consideration to the possibility of recovering molybdenum as a byproduct, as well as allowing laboratory tests that provided better understanding on the uranium leachability. Moreover, the derived the geological model will help and facilitate the exploration of the Eastern Slope of the Sierra de Pichinan District, and the regional research programmes in the San Jorge Gulf Basin as a whole. CNEA current priority in relation to the country's uranium resources, is the adoption of a policy that will permit the offering of the final feasibility study of the known orebodies and its exploitation to the private sectors. (author)

  20. Glacial lake drainage in Patagonia (13-8 kyr) and response of the adjacent Pacific Ocean

    Science.gov (United States)

    Glasser, Neil F.; Jansson, Krister N.; Duller, Geoffrey A. T.; Singarayer, Joy; Holloway, Max; Harrison, Stephan

    2016-01-01

    Large freshwater lakes formed in North America and Europe during deglaciation following the Last Glacial Maximum. Rapid drainage of these lakes into the Oceans resulted in abrupt perturbations in climate, including the Younger Dryas and 8.2 kyr cooling events. In the mid-latitudes of the Southern Hemisphere major glacial lakes also formed and drained during deglaciation but little is known about the magnitude, organization and timing of these drainage events and their effect on regional climate. We use 16 new single-grain optically stimulated luminescence (OSL) dates to define three stages of rapid glacial lake drainage in the Lago General Carrera/Lago Buenos Aires and Lago Cohrane/Pueyrredón basins of Patagonia and provide the first assessment of the effects of lake drainage on the Pacific Ocean. Lake drainage occurred between 13 and 8 kyr ago and was initially gradual eastward into the Atlantic, then subsequently reorganized westward into the Pacific as new drainage routes opened up during Patagonian Ice Sheet deglaciation. Coupled ocean-atmosphere model experiments using HadCM3 with an imposed freshwater surface “hosing” to simulate glacial lake drainage suggest that a negative salinity anomaly was advected south around Cape Horn, resulting in brief but significant impacts on coastal ocean vertical mixing and regional climate. PMID:26869235

  1. Emisiones de gases desde el fondo del lago Nahuel Huapi, Patagonia

    Directory of Open Access Journals (Sweden)

    Pablo H Vigliano

    2011-12-01

    Full Text Available Emisiones de gas en el brazo Rincón del lago Nahuel Huapi, Patagonia, son descriptas y caracterizadas en función del análisis de señales blancos ecoicos que migran desde el fondo hacia la superficie. Dichos blancos identificados como burbujas de gas, provienen en apariencia de dos fuentes distintas. Una de las señales resulta consistente con emanaciones de gases de múltiples fuentes de emisión, las cuales conforman un campo sumergido que se extiende entre los 30 y 100 m de profundidad. La otra consistente en el surgimiento de burbujas, arrastre de fluidos restos orgánicos resuspendidos y sedimentos de fondo en zonas litorales someras. Para ambos casos se analiza el posible origen de las emisiones en relación con condiciones geológicas asociadas a procesos volcánicos locales y/o a procesos biológicos.

  2. Glacial lake drainage in Patagonia (13-8 kyr) and response of the adjacent Pacific Ocean.

    Science.gov (United States)

    Glasser, Neil F; Jansson, Krister N; Duller, Geoffrey A T; Singarayer, Joy; Holloway, Max; Harrison, Stephan

    2016-01-01

    Large freshwater lakes formed in North America and Europe during deglaciation following the Last Glacial Maximum. Rapid drainage of these lakes into the Oceans resulted in abrupt perturbations in climate, including the Younger Dryas and 8.2 kyr cooling events. In the mid-latitudes of the Southern Hemisphere major glacial lakes also formed and drained during deglaciation but little is known about the magnitude, organization and timing of these drainage events and their effect on regional climate. We use 16 new single-grain optically stimulated luminescence (OSL) dates to define three stages of rapid glacial lake drainage in the Lago General Carrera/Lago Buenos Aires and Lago Cohrane/Pueyrredón basins of Patagonia and provide the first assessment of the effects of lake drainage on the Pacific Ocean. Lake drainage occurred between 13 and 8 kyr ago and was initially gradual eastward into the Atlantic, then subsequently reorganized westward into the Pacific as new drainage routes opened up during Patagonian Ice Sheet deglaciation. Coupled ocean-atmosphere model experiments using HadCM3 with an imposed freshwater surface "hosing" to simulate glacial lake drainage suggest that a negative salinity anomaly was advected south around Cape Horn, resulting in brief but significant impacts on coastal ocean vertical mixing and regional climate. PMID:26869235

  3. New evidence of the sabertooth cat Smilodon (Carnivora: Machairodontinae in the late Pleistocene of southern Chilean Patagonia Nueva evidencia del gato dientes de sable Smilodon (Carnivora: Machairodontinae en el Pleistoceno tardío de Patagonia meridional chilena

    Directory of Open Access Journals (Sweden)

    ALFREDO PRIETO

    2010-06-01

    Full Text Available Southern Patagonia is rich in late Pleistocene mammals, especially herbivores such as Camelids, Equids and Xenarthrans. Carnivores, on the other hand, are not commonly found in the paleontological record. One genus, Smilodon, is of particular interest because its presence in the region has not been demonstrated. In this paper, we present new fossil dental evidence that supports the presence of Smilodon populator (Lund in the region. This evidence corresponds to the most southern record of the genus in the world, and the final step in the colonization of South America after the Great American Biotic Interchange. An AMS radiocarbon date on teeth indicates that the remains from Southern Chilean Patagonia are the most recent record for the genus in South America.Surpatagonia es particularmente rica en mamíferos finiplesitocenos, particularmente camélidos, équidos y xenartros. Los carnívoros, por su parte, se encuentran representados en menor número en el registro paleontológico. Dentro de estos, el género Smilodon, es de particular interés debido a que su presencia en la región no ha sido convincentemente demostrada. En este trabajo presentamos evidencia dental que permite confirmar la presencia de Smilodon populator (Lund en la región. Esta evidencia corresponde al registro más sureño de este taxón y al paso final en la colonización de América del Sur después del Gran Intercambio Biótico Americano. Un fechado radiocarbónico directo AMS indica que los restos de Patagonia del Sur corresponden a los registros más tardíos para este género en el subcontinente.

  4. 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

    Directory of Open Access Journals (Sweden)

    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

  5. Transient simulations, empirical reconstructions and forcing mechanisms for the Mid-holocene hydrological climate in southern Patagonia

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Sebastian; Widmann, Martin; Jones, Julie [Institute for Coastal Research, GKSS Research Centre, Geesthacht (Germany); Haberzettl, Torsten; Ohlendorf, Christian; Zolitschka, Bernd [University of Bremen, Institute of Geography, Bremen (Germany); Luecke, Andreas; Mayr, Christoph [Research Centre Juelich, Institute of Chemistry and Dynamics of the Geosphere V, Juelich (Germany); Schaebitz, Frank [University of Cologne, Seminar for Geography and its Didactics, Cologne (Germany)

    2007-09-15

    This study investigates the atmospheric circulation in transient climate simulations with a coupled atmosphere-ocean general circulation model (GCM) for the mid-Holocene (MH) period 7-4.5 ka BP driven with combinations of orbital, solar and greenhouse gas forcings. The focus is on southern South America. Statistical downscaling models are derived from observational data and applied to the simulations to estimate precipitation in south-eastern Patagonia during the MH. These estimates are compared with lake level estimates for Laguna Potrok Aike (LPA) from sediments. Relative to pre-industrial conditions (i.e. 1550-1850), which show extraordinarily high lake levels, the proxy-based reconstructed lake levels during the MH are lower. The downscaled simulated circulation differences indicate higher LPA precipitation during the MH from March to August, higher annual means, and reduced precipitation from September to February. Thus the reconstructed lower LPA lake levels can not be explained solely by the simulated precipitation changes. Possible reasons for this discrepancy are discussed. Based on proxy data from southern South America hypotheses have also been proposed on the latitudinal position of the southern hemispheric westerlies (SHWs). In agreement with some of these hypotheses our simulations show an increased seasonal cycle of the latitudinal position of the SHWs during the MH, which can be explained by the orbital forcing. The simulations also show stronger SHWs over southern Patagonia during austral summer and weaker SHWs during winter. The downscaling model associates weaker SHWs with increased precipitation in the LPA region. However, this relationship is only moderate, and therefore the downscaling model does not support the assumption of a strong link between mean SHWs and precipitation over south-eastern Patagonia, which is the basis of many proxy-based hypotheses about the SHWs. (orig.)

  6. 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

  7. A wide diversity of zoonotic intestinal parasites infects urban and rural dogs in Neuquén, Patagonia, Argentina

    OpenAIRE

    Soriano, Silvia Viviana; Pierángeli, Nora Beatriz; Roccia, Irene; Lazzarini, Lorena Evelina; Celescinco, Alejandra; Saiz, Mónica Susana; Kossman, Alejandra; Contreras, Pablo Adrián; Arias, Cecilia; Basualdo Farjat, Juan Ángel

    2010-01-01

    The presence of parasites was investigated by the examination of 1944 dog faecal samples collected from urban (n=646) and rural (n=1298) areas of the province of Neuquén, Patagonia, Argentina. Parasitic agents (PA) were found in 37.86% of samples. A total of 15 different PA were detected, including Toxocara canis (16.35%), Taenia spp./Echinococcus spp. (12.65%), Trichurisvulpis (6.06%), Giardia spp. (1.29%), Toxascaris leonina (0.56%), Ancylostomacaninum (0.41%), Dipylidium caninum (0.31%), D...

  8. 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...

  9. Análisis ontogénico de rasgos craneofaciales robustos en poblaciones humanas de Patagonia

    OpenAIRE

    González, Paula N.

    2007-01-01

    Las poblaciones humanas que habitaron el sur de Patagonia durante el Holoceno tardío presentan rasgos craneofaciales robustos que las diferencian del resto de los humanos modernos. El estudio de los factores causales de la robustez se ha basado en el análisis de individuos adultos, por lo tanto los mecanismos ontogénicos involucrados en la diferenciación de estas poblaciones son aún desconocidos. El objetivo de este trabajo es analizar la ontogenia de la robustez craneofacial en diversas pobl...

  10. Notes for a comparison of the projects of development poles in the brazilian Amazonia and the argentinean Patagonia

    Directory of Open Access Journals (Sweden)

    Gonzalo Pérez Álvarez

    2016-04-01

    Full Text Available In this paper, we try to draw lines of comparison between the processes of development plans of subsidized industrial, installing by the National State in two big regions of Latin America: the brazilian Amazon and the argentinean Patagonia. We discussed the notion of development, debating against the equalization which was built between this concept and the growth. For this, we performed a reading of the development plans in its structural dimension, also entering the field of social and political struggles, covering for this a large and complex historical period.

  11. Incorporación del paisaje en la gestión del territorio de la Patagonia Chilena

    OpenAIRE

    Maria Dolores Muñoz; Gerardo Azócar

    2014-01-01

    Este artículo presenta una metodología para el análisis y gestión del paisaje en la Patagonia chilena, un territorio que se destaca por la belleza y diversidad de los paisajes del agua generados por la presencia de grandes lagos, ríos, fiordos, humedales y campos de hielo. El primer caso de estudio es una investigación para evaluar las potencialidades turísticas y territoriales de los paisajes del agua en la cuenca del río Baker. Se utiliza una metodología interdisciplinaria y técnicas de ...

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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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

  14. Draft Whole-Genome Sequence of Sphingobium sp. 22B, a Polycyclic Aromatic Hydrocarbon–Degrading Bacterium from Semiarid Patagonia, Argentina

    Science.gov (United States)

    Macchi, M.; Morelli, I. S.; Coppotelli, B. M.

    2016-01-01

    Sphingobium sp. 22B is a polycyclic aromatic hydrocarbon–degrading strain isolated from Patagonia, Argentina, with capabilities to withstand the environmental factors of that semiarid region. The draft genome shows the presence of genes related with responses to carbon starvation and drying environmental conditions. PMID:27257204

  15. Lake-level variations and tides in Lago Argentino, Patagonia: insights from pressure tide gauge records

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    Andreas Richter

    2015-08-01

    Full Text Available Based on precise pressure tide gauge observations lake-level records are derived for two sites in Lago Argentino, southern Patagonia, of 2.5 and 1 years of duration. Applying the tools of time series analysis, the principal processes affecting the lake level are identified and quantified. Lake-level changes reflecting variations in lake volume are dominated by a seasonal cycle of 1.2 m in amplitude. Lake-volume changes occur in addition with a daily period in response to melt water influx from surrounding glaciers. Sporadic lake-volume jumps are caused by bursting of the ice dam of Perito Moreno glacier. Water movements in Lago Argentino are dominated by surface seiches reaching 20 cm in amplitude. Lake tides reach a maximum amplitude of 3 mm. The comparison of the tidal signal extracted from the lake-level observations with a model composed of the contributions of body tide and ocean tidal loading indicates a phase shift of 23° which is most likely explained by an 1 hour phase lag of global ocean tide models in the region of the highly fragmented Pacific coast. The comparison of the obtained results with those of a previous study of Lago Fagnano, Tierra del Fuego, allows to relate differences in the hydrological and hydrodynamic processes between both lakes to morphological properties. This leads to a tentative prediction of the lake-level variability to be expected from other great Patagonian lakes. The presented geodetic results shall serve as a starting point for a detailed limnological investigation of these aquatic ecosystems.

  16. Estado actual de las investigaciones bioarqueológicas en Patagonia centro-meridional

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    Barrientos, Gustavo

    2001-01-01

    Full Text Available Desde el año 1996 se encuentran en desarrollo investigaciones en diversos sectores de Patagonia Centro-Meridional orientadas a la obtención de información bioarqueológica para discutir distintos problemas arqueológicos de alcance regional. Las mismas se hallan centradas en el estudio de la cuenca del lago Salitroso (N.O. de la provincia de Santa Cruz, aunque también se han realizado prospecciones en el lago Cardiel y pampas intermedias (del Asador y de la Chispa, que condujeron al registro y excavación de distintos tipos de estructuras funerarias (v.g. chenques y entierros en hoquedades naturales sobre rocas. Hasta el presente, las muestras recuperadas corresponden en su totalidad al lapso comprendido entre ca. 2500 a 300 años AP. Uno de los objetivos centrales de esta investigación es obtener información que permita analizar el grado y la forma de las adaptaciones (a nivel morfológico, fisiológico y organizacional alcanzadas por las poblaciones cazadoras-recolectoras del área durante el Holoceno tardío, y evaluar las condiciones previas a la extinción de las mismas en momentos históricos. El objetivo de esta presentación es exponer el conjunto de los resultados parciales obtenidos hasta el presente, a partir de la realización de análisis distribucionales, tafonómicos, paleodemográficos, isotópicos y morfológicos.

  17. Mountain frozen grounds as small amplitude thermal proxy in southern continental Patagonia

    Science.gov (United States)

    Ruiz, Sebastian; Beriain, Eneko; Izagirre, Eñaut; Bockheim, James; Pedro, Cid-Agüero

    2015-04-01

    Frozen grounds are an important element of the cryosphere, covering between a 20-25% of the global area. Frozen grounds are becoming a relevant object of research in the southern hemisphere, being most studies focused mainly on Antarctica. With the exception of seasonally frozen grounds, perennially frozen ground is found in continental South America, for example, in high altitude terrains from 4.600m a.s.l. in central Chile. However, scarce or not information regarding permafrost on Southern Patagonia has been reported. One of the aims of this study was to establish mountain permafrost existence at 1.200m in the southern limit of the Southern Patagonian Ice-Field, a geographically active area surrounded by different kinds of glaciers on fast retreat. The area of study presents several features of past cryogenic activity such as undefined polygonal grounds with a thick clast border and sandy-loam interior. A scarce vegetal cover is limited to lichen and moss communities. The analyzed soil does not represent a thermal barrier that may avoid heat wave dynamic along the ground profile. There was neither significant snow-cover during winter nor a vegetation layer enough to consider as insulation for the analyzed ground. Oscillations above 0°C were evidenced down to 1.8m depth during winter of 2014, ruling out the existence of permafrost at that lower limit. Year round thermal dynamic down to 1.8m in the ground profile is presented as one result of the monitoring. Small amplitude temperature fluctuations were registered upon monitoring. These minimal amplitudes were stable throughout several months and as such serve as an interesting proxy for recent and long-term climatic thermal fluctuation. The influence of winds coming from nearby glaciers highly affects near-surface amplitude. This interaction was studied. The present work is part of an ongoing monitoring network along South America that intends to fill the gap between tropical Andes and the Antarctic Peninsula.

  18. INCORPORACIÓN DEL PAISAJE EN LA GESTIÓN DEL TERRITORIO DE LA PATAGONIA CHILENA

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    MARÍA DOLORES MUÑOZ

    2014-01-01

    Full Text Available Este artículo presenta una metodología para el análisis y gestión del paisaje en la Patagonia chilena, un territorio que se destaca por la belleza y diversidad de los paisajes del agua generados por la presencia de grandes lagos, ríos, fiordos, humedales y campos de hielo. El primer caso de estudio es una investigación para evaluar las potencialidades turísticas y territoriales de los paisajes del agua en la cuenca del río Baker. Se utiliza una metodología interdisciplinaria y técnicas de medición, cualitativa y cuantitativa, que permitieran analizar los valores espaciales, ambientales, territoriales y culturales asociados al paisaje. Un aspecto esencial fue incorporar la valoración social del paisaje. El segundo caso, ubicado en el estrecho de Magallanes, corresponde a una metodología de análisis territorial como base para diseñar un Plan de Manejo Turístico en el Área Marina Protegida Francisco Coloane (que incluye al Parque Marino Francisco Coloane. Comprende el análisis de las condiciones ambientales, las características del paisaje y potencialidades del turismo de intereses especiales asociado al paisaje para respaldar la propuesta de gestión. En ambos casos, la metodología considera al paisaje como principal recurso territorial y plantea una forma de gestión respaldada por principios de sustentabilidad ambiental y social.

  19. The origin of oriented lakes in the Andean foreland, Parque Nacional Torres del Paine (Chilean Patagonia)

    Science.gov (United States)

    Gonzales, Joseph; Aydin, Atilla

    2008-05-01

    The Parque Nacional Torres Del Paine and surrounding area in the Magallanes foreland basin in Chilean Patagonia is the site for numerous lakes fed by glaciers and rivers in the Andean highlands to the west. The lakes are elongate and have conspicuously systematic orientations. We hypothesize that the origin of the oriented lakes lies in the fault system, composed of a right-lateral strike-slip fault set oriented 58° from north, a left-lateral strike-slip set oriented 87°, and a thrust fault set oriented 167°, that exists within the underlying rocks. To test this hypothesis quantitatively, we determined the shape and orientation of the lakes by fitting each lake with an ellipse of appropriate aspect ratio, and later with multiple ellipses consistent with the composite geometry of some lakes. We then examined the faults in the area in terms of their kinematics, orientation and distribution. The distribution of lake orientations showed three distinct groups which appear to correspond to the three main fault groups. For lakes fitted with multiple ellipses, the difference in means between the right-lateral, left-lateral, and thrust faults and their corresponding groups of lakes are 3.05°, 1.57°, and 5.17°. Using a Kolmogorov-Smirnov (K-S) statistical test to compare the orientations of faults with respect to the lakes suggests that there is not a strongly significant difference between the fault orientations and the corresponding lake groups. These results indicate that the faults have a profound control on the orientation, shape, and distribution of the lakes. We attribute this to faults and their damage zones being weaker and therefore prone to a faster rate of erosion, and to stress perturbations associated with discontinuous faults resulting in localized high density fracturing and surface subsidence. These results have implications for lake and drainage system morphologies in other foreland basins along the Andes and other similar settings.

  20. 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)

  1. 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.

  2. Novel aromatic ring-hydroxylating dioxygenase genes from coastal marine sediments of Patagonia

    Directory of Open Access Journals (Sweden)

    Ferrero Marcela A

    2008-03-01

    Full Text Available Abstract Background Polycyclic aromatic hydrocarbons (PAHs, widespread pollutants in the marine environment, can produce adverse effects in marine organisms and can be transferred to humans through seafood. Our knowledge of PAH-degrading bacterial populations in the marine environment is still very limited, and mainly originates from studies of cultured bacteria. In this work, genes coding catabolic enzymes from PAH-biodegradation pathways were characterized in coastal sediments of Patagonia with different levels of PAH contamination. Results Genes encoding for the catalytic alpha subunit of aromatic ring-hydroxylating dioxygenases (ARHDs were amplified from intertidal sediment samples using two different primer sets. Products were cloned and screened by restriction fragment length polymorphism analysis. Clones representing each restriction pattern were selected in each library for sequencing. A total of 500 clones were screened in 9 gene libraries, and 193 clones were sequenced. Libraries contained one to five different ARHD gene types, and this number was correlated with the number of PAHs found in the samples above the quantification limit (r = 0.834, p nahAc-like genes, phnAc-like genes as identified in Alcaligenes faecalis AFK2, and phnA1-like genes from marine PAH-degraders from the genus Cycloclasticus. Conclusion These results show the presence of hitherto unidentified ARHD genes in this sub-Antarctic marine environment exposed to anthropogenic contamination. This information can be used to study the geographical distribution and ecological significance of bacterial populations carrying these genes, and to design molecular assays to monitor the progress and effectiveness of remediation technologies.

  3. 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.

  4. Linking geomorphology and hydrodynamics: a case study from Península Valdés, Patagonia, Argentina

    Science.gov (United States)

    Del Pilar Alvarez, María; Weiler, Nilda E.; Hernández, Mario A.

    2010-03-01

    A case study is presented to assess the relevance of geomorphology in hydrogeological phenomena in an arid coastal area in the Argentinean extra-Andean Patagonia (Península Valdés) with an average rainfall of 232 mm/year and a soil moisture deficit of about 472 mm/year. Various geomorphic units were identified by interpreting Landsat 7 satellite images processed with ER Mapper software and then surveyed in the field, as well as by geological characterization. The hydrodynamic analysis was based on a survey of 89 wells, the construction of equipotential maps, and the interpretation of pumping-test results by a non-equilibrium method. The hydrochemical characterization was based on chemical tests analyzed with the Easy_Quim 6.0 application. The combination of geomorphological, geological, hydrodynamic and hydrochemical elements allowed the definition of hydromorphological units that are typical of recharge, circulation and discharge areas, the latter both for coastal and inland areas in wetlands (salt pans) with elevations to -40 m relative to sea level. These units and the criteria used for their definition allow immediate recognition of hydrogeological phenomena in arid regions such as the extra-Andean Patagonia, with low information density but with near-optimal satellite imaging of landforms due to the lack of vegetation cover.

  5. 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

    Full Text Available El viaje del Beagle que trajo a Charles Darwin a América del Sur entre 1832 y 1835 AD y en particular, al territorio argentino, se desarrolló bajo condiciones climáticas muy desfavorables: frías, secas y ventosas, correspondientes a las condiciones predominantes en la última fase de la pequeña edad del hielo, un episodio frío global que caracterizó a los siglos XVII, XVIII y XIX. Esta fase es conocida como mínimo de Dalton, en referencia a la disminución relativa de la frecuencia de las manchas solares, lo cual redunda en una disminución de la radiación solar y como consecuencia, en menores temperaturas medias globales en ese período. Darwin fue perfectamente consciente de dichas condiciones climáticas, que se manifestaban fuertemente en Europa, en particular en los Alpes, y así lo transmite en sus escritos. Desde el viaje de Darwin a la Patagonia, las condiciones climáticas y ambientales cambiaron sustancialmente, especialmente luego de 1850 AD y, finalmente, después de mediados de la década de 1970 AD. Algunas de las más importantes consecuencias del cambio climático global son el aumento de la temperatura media anual o la temperatura estacional, la elevación o disminución de las precipitaciones al nivel regional, el continuo ascenso global del nivel del mar y un incremento significativo de la frecuencia de eventos meteorológicos extremos. El impacto de esos cambios ha sido observado en los glaciares de Patagonia y Tierra del Fuego, por lo menos desde 1978 AD, y particularmente en la última década del siglo XX. Los impactos más notables son la rápida recesión de las márgenes del hielo en los glaciares, el adelgazamiento de la cobertura glacial, la elevación de la línea de nieve regional y la reducción de las áreas andinas bajo condiciones de suelos permanentemente congelados (permafrost, como han demostrado estudios científicos recientes. A la tasa presente de recesión del hielo glacial, la mayoría, si no

  6. 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.

  7. Ignition probability of fine dead surface fuels in native Patagonia forests of Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, L.; Defosse, G. E.

    2014-06-01

    Aim of study: The Canadian Forest Fire Weather Index (FWI) is being implemented all over the world. This index is being adapted to the Argentinean ecosystems since the year 2000. With the objective of calibrating the Fine Fuel Moisture Code (FFMC) of the FWI system to Patagonian forests, we studied the relationship between ignition probability and fine dead surface fuel moisture content (MC) as an indicator of potential fire ignition. Area of study: The study area is located in northwestern Patagonia, Argentina, and comprised two main forest types (cypress and nire) grown under a Mediterranean climate, with a dry summer and precipitations during winter and autumn ({approx}500-800 mm per year). Material and methods: We conducted lab ignition tests fires to determine the threshold of fine dead fuel ignition at different MC levels. Moisture content of dead fine surface fuels in the field was measured every 10-15 days from November to March for three seasons. We calculated the FFMC during these seasons and correlated it with the measured MC by applying a logistic regression model. We combined the results of the ignition tests and of the regressions to suggest FFMC categories for estimating fire danger in Patagonian forests. Main results: The ignition threshold occurred at MC values of 21.5 and 25.0% for cypress and nire sites, respectively. The MC measured varied from 7.3 to 129.6%, and the calculated FFMC varied between 13.4 and 92.6. Highly significant regressions resulted when FFMC was related to MC. The ignition threshold corresponded to a FFMC = 85. We proposed to divide the FFMC scale in three fire danger categories: Low (FFMC {<=} 85), High (85 < FFMC{<=}89) and Extreme (FFMC > 89). Research highlights: Our results provide a useful tool for predicting fire danger in these ecosystems, and are a contribution to the development of the Argentinean Fire Danger Rating and a reference for similar studies in other countries where the FWI is being implemented. (Author)

  8. Silver contamination on abiotic and biotic compartments of Nahuel Huapi National Park lakes, Patagonia, Argentina

    International Nuclear Information System (INIS)

    The Ag contents of abiotic and biotic compartments of different lakes of Nahuel Huapi National Park, Patagonia, Argentina were analyzed. The water bodies studied were lakes Nahuel Huapi, Moreno, Escondido, Espejo Chico and Traful, the latter chosen as a reference lake. The Ag concentration profiles of short sediment cores, dated by 210Pb and 137Cs techniques, were analyzed, as well as suspended load collected from three sites of lake Nahuel Huapi. The biota studied were the native mussel Diplodon chilensis (digestive gland and total soft tissues pooled samples) and five species of fish, two native and three introduced (liver and muscle pooled samples). Ag contents were determined by Instrumental Neutron Activation Analysis (INAA). The upper layers of the sediment cores sampled in lake Nahuel Huapi were enriched in Ag contents compared to deep layers in accumulation periods corresponding to the second half of the 20th century, but this enrichment was neither observed in the reference lake Traful, nor in lakes Espejo Chico and Escondido. Ag was enriched over background level (0.1 μg g-1) also in suspended load collected in lake Nahuel Huapi. Ag fluxes to sediments were computed for suspended load and enriched sediment core layers. Highest Ag fluxes, from 350 to 470 μg m-2 year-1, were measured in Nahuel Huapi near the site where the liquid effluents of the Bariloche city sewage treatment plant are released to the lake. The spatial distribution of the other Ag fluxes suggests that this is the main source of Ag to lake Nahuel Huapi and lateral transport occurs within the water body. Ag concentrations on biota samples were consistent with these conclusions. Mussels collected in lake Nahuel Huapi showed higher Ag concentrations than in the other lakes, especially when compared to lake Traful. Ag contents in mussels were strongly associated with sediment intake, but enriched probably due to sediment grain size sorting during the intake processes. Evidence of food chain

  9. Peat decomposition records in three pristine ombrotrophic bogs in southern Patagonia

    Directory of Open Access Journals (Sweden)

    T. Broder

    2012-04-01

    Full Text Available Ombrotrophic bogs in southern Patagonia have been examined with regard to paleoclimatic and geochemical research questions but knowledge about organic matter decomposition in these bogs is limited. Therefore, we examined peat humification with depth by Fourier Transformed Infrared (FTIR measurements of solid peat, C/N ratio, and δ13C and δ15N isotope measurements in three bog sites. Peat decomposition generally increased with depth but distinct small scale variation occurred, reflecting fluctuations in factors controlling decomposition. C/N ratios varied mostly between 40 and 120 and were significantly correlated (R2 > 0.55, p < 0.01 with FTIR-derived humification indices. The degree of decomposition was lowest at a site presently dominated by Sphagnum mosses. The peat was most strongly decomposed at the driest site, where currently peat-forming vegetation produced less refractory organic material, possibly due to fertilizing effects of high sea spray deposition. Decomposition of peat was also advanced near ash layers, suggesting a stimulation of decomposition by ash deposition. Values of δ13C were 26.5 ± 2‰ in the peat and partly related to decomposition indices, while δ15N in the peat varied around zero and did not consistently relate to any decomposition index. Concentrations of DOM partly related to C/N ratios, partly to FTIR derived indices. They were not conclusively linked to the decomposition degree of the peat. DOM was enriched in 13C and in 15N relative to the solid phase probably due to multiple microbial modifications and recycling of N in these N-poor environments. In summary, the depth profiles of C/N ratios, δ13C values, and FTIR spectra seemed to reflect changes in environmental conditions affecting decomposition, such as bog wetness, but were dominated by site specific factors, and are further influenced by ash

  10. A Sedimentological Multi-Proxy Study of Late Holocene Climate Change in Southern Patagonia

    Science.gov (United States)

    Hutchinson, E. C.; Leroy, S. L.; Dunbar, R. B.

    2014-12-01

    The southern hemisphere westerlies force and respond to circulation and heat exchange with the Southern Ocean, which in turn plays a large role in global climate change. Southern Patagonia is the only significant land mass in the path of the southern westerlies, so it is an ideal location to examine variability of this wind system and its relation to regional and global climate. Precipitation and wind strength exhibit a strong positive correlation, and we take advantage of this relationship to use a paleoclimate archive to probe past changes in the wind field. We examined a 3.6m long sediment core from Lago Sarmiento (51.06˚S, 72.91˚W) in Torres del Paine National Park, Chile, for indicators of past environmental change. Here we present a high resolution, multi-proxy record of regional paleoclimate that includes physical, biological, and chemical data sets. We measured magnetic susceptibility, weight percent organic carbon and nitrogen, δ13C of bulk sediment, and weight percent carbonate of the core. These results provide information about precipitation, relative wind strength, volcanic activity, and biological productivity in and around Lago Sarmiento over the past 4,000 years. Our age model for the core is based in part on tephrochronology. We identified three tephras, or volcanic ashes, in the core at 68-71, 110-112, and 284-286cm that are supported visually and with magnetic susceptibility measurements. Analysis of the C:N ratio of the Lago Sarmiento core demonstrates a long-term increase in the deposition of terrestrial organic matter in Lago Sarmiento over time, perhaps indicating a change from grassland to woodland due to increased precipitation. The largest excursions in the C:N ratio occur at 20, 53, 139-140, 225-226, and 252cm. The average δ13C of organic carbon is -24.81‰, and large decreases occur at 9, 45, 180, 245-246, and 252-253cm, which could indicate overturning events in the lake. The average weight percent carbonate is 18%, with large

  11. A Combined Observational and Modeling Approach to Study Modern Dust Transport from the Patagonia Desert to East Antarctica

    Science.gov (United States)

    Gasso, S.; Stein, A.; Marino, F.; Castellano, E.; Udisti, R.; Ceratto, J.

    2010-01-01

    The understanding of present atmospheric transport processes from Southern Hemisphere (SH) landmasses to Antarctica can improve the interpretation of stratigraphic data in Antarctic ice cores. In addition, long range transport can deliver key nutrients normally not available to marine ecosystems in the Southern Ocean and may trigger or enhance primary productivity. However, there is a dearth of observational based studies of dust transport in the SH. This work aims to improve current understanding of dust transport in the SH by showing a characterization of two dust events originating in the Patagonia desert (south end of South America). The approach is based on a combined and complementary use of satellite retrievals (detectors MISR, MODIS, GLAS ,POLDER, OMI,), transport model simulation (HYSPLIT) and surface observations near the sources and aerosol measurements in Antarctica (Neumayer and Concordia sites). Satellite imagery and visibility observations confirm dust emission in a stretch of dry lakes along the coast of the Tierra del Fuego (TdF) island (approx.54deg S) and from the shores of the Colihue Huapi lake in Central Patagonia (approx.46deg S) in February 2005. Model simulations initialized by these observations reproduce the timing of an observed increase in dust concentration at the Concordia Station and some of the observed increases in atmospheric aerosol absorption (here used as a dust proxy) in the Neumayer station. The TdF sources were the largest contributors of dust at both sites. The transit times from TdF to the Neumayer and Concordia sites are 6-7 and 9-10 days respectively. Lidar observations and model outputs coincide in placing most of the dust cloud in the boundary layer and suggest significant de- position over the ocean immediately downwind. Boundary layer dust was detected as far as 1800 km from the source and approx.800 km north of the South Georgia Island over the central sub-Antarctic Atlantic Ocean. Although the analysis suggests the

  12. 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

  13. Distribución del ictioplancton en la Patagonia austral de Chile: potenciales efectos del deshielo de Campos de Hielo Sur Ichthyoplankton distribution in South Patagonia, Chile: potential effects of ice melting from the Southern Ice Field

    Directory of Open Access Journals (Sweden)

    Mauricio F Landaeta

    2011-07-01

    Full Text Available Durante octubre-noviembre de 2009 se realizó un crucero oceanográfico entre 50 y 53°S de Chile austral, en las cercanías del glaciar Campos de Hielo Sur. Las estaciones cercanas al glaciar presentaron baja temperatura (1-3°C y salinidad ( 0,1 ciclos s-1. Los principales taxa del ictioplancton fueron huevos y larvas de sardina fueguina Sprattus fuegensis, pez hacha Maurolicus parvipinnis, Macrouridae y merluza austral Merluccius australis. El desove principal de S. fuegensis (~ 8000 huevos 10 m-2 ocurrió en zonas mezcladas de la plataforma continental adyacente, mientras que el desove de M. parvipinnis ocurrió en canales intermedios asociado a valores intermedios de estabilidad (N~0,06 ciclos s-1. Se observó una nula o baja abundancia de huevos y larvas de peces en las cercanías del glaciar, y la abundancia de huevos de M. parvipinnis estuvo relacionada positivamente con la temperatura y salinidad de la columna de agua y negativamente con la estabilidad de la columna de agua. Además, hubo una relación negativa entre la densidad del agua de mar y el diámetro de los huevos de S. fuegensis. La relación entre deshielo e ictioplancton podría tener consecuencias en el transporte advectivo y mortalidad masiva de huevos y larvas de peces y el acople pelágico-bentónico en la Patagonia austral de Chile. Como el cambio climático global ha incrementado los deshielos de glaciares en latitudes altas, y el aumento del ingreso de aguas de baja temperatura y salinidad podría tener consecuencias en el ictioplancton de la Patagonia chilena.In October-November 2009, an oceanographic survey was carried out between 50 and 53°S off southern Chile, near the Southern Ice Field. The stations near the glacier showed low temperatures (1-3°C and salinity ( 0.1 cycles s-1. Main ichthyoplankton taxa were eggs and larvae of southern sprat Sprattus fuegensis, lightfish Maurolicus parvipinnis, Macrouridae, and southern hake Merluccius australis. The main

  14. Cenozoic back-arc magmatism of the southern extra-Andean Patagonia (44° 30' - 52° S: A review of geochemical data and geodynamic interpretations

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    M. D'Orazio

    2004-12-01

    Full Text Available Huge amounts of basaltic s.l. lavas were persistently erupted along the eastern side of the Andean Cordillera, throughout Cenozoic time, forming extensive plateaus, hundreds of monogenetic scoria cones and other volcanic structures in a continental back-arc setting. The igneous products exposed in the southern sector of the extra-Andean Patagonia (44° 30' - 52° S are dominantly mafic with minor slightly evolved compositions and rare highly differentiated products. The many published chemical analyses of these rocks, indicate that the mafic lavas range from strongly silica - undersaturated basanites to oversaturated basaltic andesites, and that most of the lavas have a typical within-plate geochemical signature. However, a number of lavas, generally erupted in the western-central sectors of Patagonia, are characterized by different distributions of the incompatible elements with high LILE/HFSE and LREE/HFSE ratios. The REE distribution modelling suggests a low degree of melting of a deep (> 70 km garnet-bearing source for the alkaline magmas, and a higher degree of melting of the same source, or an even higher degree of melting of an enriched source, for the subalkaline magmas. The available Sr-Nd-Pb isotope compositions clearly attest to a major geographic variation: the southernmost lavas have lower 87Sr/86Sr and higher 143Nd/144Nd and 206Pb/204Pb ratios with respect to those erupted to the north. On the whole, the Sr-Nd-Pb isotope compositions of the southern Patagonia lavas fall within the typical range of within-plate continental magmas; in addition the Pb isotope ratios fall in the range of the Southern Hemisphere Dupal Pb isotope anomaly. The geochemical variations of the southern Patagonia lavas are discussed in terms of different geochemical components: depleted and enriched sub-slab asthenosphere, enriched continental lithospheric mantle, continental crust and subducted materials. The geodynamic significance is interpreted with in the

  15. 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

  16. Dieta y dinámica poblacional del león marino del sur ("Otaria flavescens") en Patagonia

    OpenAIRE

    Drago, Massimiliano

    2010-01-01

    El león marino del sur (Otaria flavescens), al igual que otros pinnípedos, fue intensamente perseguido por su piel y grasa. En Patagonia se estima que en la década de 1960, cuando cesó la explotación, la población se había reducido a menos del 10% de su tamaño original y permaneció sin crecer hasta la década de 1980. La reducción drástica de la población de león marino del sur no fue el único impacto humano en el ecosistema marino, ya que simultáneamente al cese de su explotación se inició la...

  17. 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

  18. Charles Darwin and the oldestglacial events in Patagonia: the erratic blocks of the Río Santa Cruz valley

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    Jorge Strelin

    2009-04-01

    Full Text Available Althoughthe depositational environment assigned by Darwin to the large erratic blocksand gravels in the Río Santa Cruz valley has been reinterpreted, hisgeomorphological and stratigraphic observations are still in force. The largeerratic blocks he described as crowning the Condor Cliff terrace and spread atthe bottom of the valley just east of this locality (Sites 2 and 3, are nowinterpreted as indicators of the maximum glacial expansion in Patagonia.Similar blocks, though of a different lithology, accumulated over a lowerterrace located up-valley (Site 4, are now linked to moraines and glacifluvialterraces of the Penultimate Glaciation. Finally, in addition to the erraticblock discovered by Darwin in the lower Río Santa Cruz valley (Site 1, thereare others - recently discovered - which probably account for a catastrophicevent ascribed to a big glacier-lake outburst during the last interglacial.

  19. Genetics Home Reference: Northern epilepsy

    Science.gov (United States)

    ... Understand Genetics Home Health Conditions Northern epilepsy Northern epilepsy Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Northern epilepsy is a genetic condition that causes recurrent seizures ( ...

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

    Science.gov (United States)

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

    2016-02-01

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

  1. Análisis ontogénico de rasgos craneofaciales robustos en poblaciones humanas de Patagonia

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    González, Paula N.

    2007-01-01

    Full Text Available Las poblaciones humanas que habitaron el sur de Patagonia durante el Holoceno tardío presentan rasgos craneofaciales robustos que las diferencian del resto de los humanos modernos. El estudio de los factores causales de la robustez se ha basado en el análisis de individuos adultos, por lo tanto los mecanismos ontogénicos involucrados en la diferenciación de estas poblaciones son aún desconocidos. El objetivo de este trabajo es analizar la ontogenia de la robustez craneofacial en diversas poblaciones humanas. Se analizaron 5 muestras de individuos subadultos (Sad, de 5 a 15 años y adultos (Ad, procedentes del Noroeste Argentino y Patagonia (n=201. Se emplearon landmarks y semilandmarks con el fin de describir la glabela, los procesos frontal y zigomático, y el mastoides. Para establecer si los rasgos poblacionales específicos se encuentran presentes en Sad se compararon los patrones de ordenación de Ad y Sad obtenidos mediante un análisis de PROTEST. Los resultados indican que el patrón de variación morfológica se establece tempranamente en Sad. Se evaluó si la diferenciación en los Ad de las diversas poblaciones es atribuible al escalamiento ontogénico o a diferencias en las trayectorias. Los resultados muestran que si bien las poblaciones del sur alcanzan un mayor tamaño, las trayectorias ontogénicas entre las poblaciones estudiadas difieren significativamente. Por lo tanto, la robustez se establece tempranamente en la ontogenia postnatal y es modificada por la divergencia en los patrones de cambio en forma asociados a los cambios en tamaño.

  2. Vegetation, Fire and Climate Over the Last 2000 Yrs in Central West Patagonia (45°S)

    Science.gov (United States)

    Villa-Martinez, R. P.; Simi, E. I.; Moreno, P. I.

    2014-12-01

    We report high-resolution pollen and charcoal records from lake sediments obtained from Lago Mellizas and Lago Churrasco to reconstruct the history of vegetation, fire and past variations of the southern westerly winds (SWW) over the last 2000 years. Both sites are located near to the climate-modulated forest-steppe ecotone in central west Patagonia. In this region the SWW are the only source of precipitation and is ideal for reconstructing past changes in atmospheric circulation. This is facilitated by the marked west-east precipitation gradient across the Patagonian Andes that induces a zonation of the regional vegetation which can be used for inferring past changes in precipitation regimes based on fossil pollen records. Furthermore, the Chilean-European colonization process in central west Patagonia started early in the 20th century, allowing characterization of natural vegetation and climate variability in the absence of human disturbance until the end of the 19th century. The pollen records shows dominance of Nothofagus deciduous forests with minor fluctuations and low herb and aquatics abundances, which suggest humid climate conditions. We detect a major change in the pollen stratigraphy at 200 cal yr BP, when started a sustained decreasing trend in Nothofagus, along with increases of Poaceae and aquatics plants (Cyperaceae, Myriophyllum). We interpret these changes as a forest opening and centripetal expansion of littoral environments toward the lake center driven by lake-level lowering in response to lowered precipitation brought by the SWW. Pinus, Rumex, Plantago, which indicate human perturbation, increase in 1900 AD. Macroscopic charcoal increases at 1750, 1400, 850-700, 500, and 200 cal yr BP, suggesting local fires, followed by sharp increases during the last 100 years. We interpret the pre-20th century charcoal peaks as dry intervals with lowered SWW influence. Acknowledgement: Fondecyt 1121141, Fondap 15110009, and ICM grants P02-51 and NC120066.

  3. OBSERVATORIO DE LAS TECNOLOGÍAS EN LA EDUCACIÓN EN LA PATAGONIA: EL PROCESO DE ELABORACIÓN Y SELECCIÓN DE INDICADORES.

    Directory of Open Access Journals (Sweden)

    Silvia Gonzalez

    2013-01-01

    Full Text Available Este trabajo describe el proceso de elaboración de un conjunto de indicadores aplicando la técnica Delphi. Con esos indicadores el Observatorio de las Tecnologías en la Educación en la Patagonia, con la finalidad de orientar políticas educativas que tiendan a promover la inclusión digital, estudiará el acceso y uso de las TIC para producir y difundir información oportuna, actualizada, relevante y académicamente confiable. La investigación se realiza en el marco del Proyecto D/030419/10 Implantación de red de vinculación digital de la Patagonia Austral (REVINDIPA para el desarrollo comunitario, que corresponde al año 2011.

  4. 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.

  5. 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...

  6. A large accumulation of avian eggs from the Late Cretaceous of Patagonia (Argentina) reveals a novel nesting strategy in Mesozoic birds

    OpenAIRE

    Fernández, Mariela; Garcia, Rudolfo; Fiorelli, Lucas; Scolaro, Alejandra; Salvador, Rodrigo; Cotaro, Carlos; Kaiser, Gary; Dyke, Gareth

    2013-01-01

    We report the first evidence for a nesting colony of Mesozoic birds on Gondwana: a fossil accumulation in Late Cretaceous rocks mapped and collected from within the campus of the National University of Comahue, Neuquén City, Patagonia (Argentina). Here, Cretaceous ornithothoracine birds, almost certainly Enanthiornithes, nested in an arid, shallow basinal environment among sand dunes close to an ephemeral water-course. We mapped and collected 65 complete, near-complete, and broken eggs across...

  7. APOROCOTYLE MARIACHRISTINAE N. SP., AND A. YMAKARA VILLALBA & FERNANDEZ, 1986 (DIGENEA: APOROCOTYLIDAE) OF THE PINK CUSK-EEL, GENYPTERUS BLACODES (OPHIDIIFORMES: OPHIDIIDAE) FROM PATAGONIA, ARGENTINA

    Czech Academy of Sciences Publication Activity Database

    Hernandez-Orts, J.S.; Alama-Bermejo, Gema; Carillo, J.M.; García, N.A.; Crespo, E.A.; Raga, J. A.; Montero, E. E.

    2012-01-01

    Roč. 19, č. 4 (2012), s. 319-330. ISSN 1252-607X R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Aporocotylidae * Aporocotyle * A. mariachristinae n. sp. * A. ymakara * Genypterus blacodes * Ophidiidae * Patagonia * Argentina * rDNA sequences Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.116, year: 2012

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

    OpenAIRE

    Paula Gabriela Núñez; Brenda Matossian; Laila Vejsbjerg

    2012-01-01

    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 administ...

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

    Science.gov (United States)

    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

  10. The shallow-water chitons (Mollusca, Polyplacophora of Caldera, Region of Atacama, northern Chile

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    Juan Francisco Araya

    2015-03-01

    Full Text Available The Molluscan species of the northern littoral of Chile have been sparsely studied. This work reviews for the first time the diversity of polyplacophoran molluscs around the port of Caldera, in the Region of Atacama (26°45’49”S; 70°45’17”W to 27°20’23”S; 70°56’46”W, northern Chile. Eleven species were found in this study: Acanthopleura echinata (Barnes, 1824; Callistochiton pulchellus (Gray, 1828; Calloplax vivipara (Plate, 1899, Chaetopleura peruviana (Lamarck, 1819; Chiton cumingsii Frembly, 1827; Chiton granosus Frembly, 1827; Chiton magnificus Deshayes, 1827; Enoplochiton niger (Barnes, 1824, Radsia barnesii (Gray, 1828, Tonicia atrata (G. B. Sowerby II, 1840 and Tonicia chilensis (Frembly, 1827. All of the species occurring in the area have distributions in the southeastern Pacific Ocean, from Ecuador to central Chile, and three of them are species endemic to the Chilean coasts (Calloplax vivipara, Radsia barnesii, and Tonicia atrata. This diversity of species is comparable to that of better surveyed faunas of central and southern Chile or Patagonia. Of the eleven species recorded, the geographic distribution records for Callistochiton pulchellus, Radsia barnesii and Tonicia atrata are extended, and Calloplax vivipara is found alive again after 40 years, filling a gap in its known distribution. Illustrations of living specimens in their habitat, distribution records and a taxonomic key for all the studied taxa are also provided.

  11. Northern Lights Chase Tours : Experiences from Northern Norway

    OpenAIRE

    Bertella, Giovanna

    2013-01-01

    This study is focused on the development of northern lights chase tourism, a particular type of northern lights tourism consisting in guided tours that have the goal to find good views of the northern lights. The theoretical approach is based on the understanding of the northern lights experience as a visual experience, and on the recognition of the tourism practitioners as the driving force to new product development. The empirical case concerns the recent development of northern lights chas...

  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. 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

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    SEBASTIÁN BELMAR-LUCERO

    2009-06-01

    Full Text Available At present, 20 species of Oligoryzomys (Rodentia, Sigmodontinae are recognized in the Neotropical region, most of them distinguished by their karyotypes, which fluctuates between 46-70 chromosomes. Two species are currently recognized in Chile, Oligoryzomys longicaudatus (Bennet, 1832; "colilargo" or the long-tailed pygmy rice rat; 2n = 56, which ranges from 27° to approximately 51° S, and O. magellanicus (Bennet, 1836; Magellanic pygmy rice rat; 2n = 54, south of 51° S in the Patagonian region of Chile and Argentina. As part of an ongoing research on the southern Patagonia of Chile, we report the results of small mammal samplings in six localities. We karyotyped 28 specimens and we also sequenced the hypervariable mtDNA region I in 22 individuals, aligning these sequences with an under development phylogeny of O. longicaudatus. We also evaluated the serology and viral charge in all captured specimens to detect the presence of antibodies to Andes virus (ANDV through Strip Immunoblot Assay (SIA, and of viral genome by RT-PCR. The results consistently showed that the karyotype of southern Patagonia specimens was 2n = 56, equal to that of O. longicaudatus, and that individuals from this area do not differentiate phylogenetically from those of the northern range of distribution. In addition, the serology showed the presence of antibodies IgG anti-ANDV and of viral genome in heart, kidney, spleen, and lungs of a single specimen of Oligoryzomys from the locality of Fuerte Bulnes in the Magallanes region. We conclude that all specimens trapped south of 51° S correspond to Oligoryzomys longicaudatus, thus expanding the distribution of this specie! from 51° to at least 55° S. The results also extended the disiribution of the Andes strain of Hantavirus to southernmost Patagonia.Actualmente se reconocen 20 especies de Oligoryzomys (Rodentia, Sigmodontinae en la región Neotropical, la mayoría de ellas distinguidas por sus cariotipos, los que fluct

  14. 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

  15. Reconstruction and modelling of the 1977 Glacial Lake Outburst Flood (GLOF) of the Engaño Lake, Chilean Patagonia.

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    Iribarren Anacona, Pablo; Norton, Kevin; Mackintosh, Andrew

    2015-04-01

    Floods from moraine-dammed lake failures can result in severe damage to mountain communities. GLOFs can also cause long-standing effects in riverine landscapes, due to the high intensity (i.e. great depth and high velocities) and long reach capacity of these events. GLOFs may increase in frequency as glaciers retreat and new lakes develop, highlighting the need for a better understanding of GLOF dynamics and the measures to reduce their negative outcomes. In Patagonia at least 16 moraine-dammed lakes have failed in historic time, however, data about GLOF dynamics and impacts are limited since GLOFs have mainly affected uninhabited areas and ungauged rivers. In March 1977, however, a GLOF flooded a small village (~130 inhabitants) in Chilean Patagonia. We reconstruct the dynamics of this event by semi-structured interviews, interpretation of satellite images (Landsat MSS) and two dimensional (2D) hydraulic modelling (using HEC-RAS 5.0 BETA and the SRTM v4 DEM). This reconstruction provides insights into GLOF behaviour, as well as the planning issues that led to socioeconomic consequences, which included relocation of the village. We mapped the flood extent and compiled data of flood depth and timing to constrain the 2D GLOF simulations. Modelling shows that the water released by the GLOF was in the order of 12-13 million cubic metres and that the flood reached Bahía Murta Viejo, located ~26 km from the failed lake, 2-3 hours after the moraine dam was breached. The flood lasted for about ten hours (at the village), although the peak discharge occurred after only one hour at this site. The maximum water depth at Bahía Murta Viejo was 1.5 m, however, water depths of up to 20 metres were simulated in upstream constricted reaches. The overall flood dynamics suggested by interviews and geomorphic mapping, including hydraulic ponding upstream of bedrock gorges, was well represented in the 2D simulations in spite of the coarse resolution (~80 m) of the DEM used. The

  16. Tafonomía regional en la cuenca media del río Coyle (Santa Cruz, Patagonia Argentina

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    Juan Bautista Belardi

    2003-12-01

    Full Text Available Se presenta una base de datos tafonómicos para guanaco (Lama guanicoe y choique (Pterocnemia pennata, obtenida como resultado de estudios de impacto ambiental (EsIA en la cuenca media del río Coyle, en la Patagonia meridional argentina. La información se reseña de acuerdo con dos Unidades de paisaje: Terrazas y Fondo de valles, que resultan adecuadas como unidades de análisis espacial y a partir de las cuales se generan expectativas tafonómicas. Se discute el grado de superposición y mezcla potencial entre contextos arqueológicos y restos óseos depositados naturalmente. Luego se analizan distintas variables tafonómicas para cada especie dentro de las Unidades de paisaje y se compara la información obtenida. Los resultados alcanzados indican que bajo las condiciones actuales, la probabilidad de contaminación de contextos arqueológicos por huesos depositados naturalmente en Terrazas y Fondo de valles es muy baja. Sin embargo, en el pasado, la mayor lluvia de huesos naturales y la más densa cobertura vegetal habrían creado condiciones más favorables para que ello sucediera. Esta información, junto con la resultante de las variables tafonómicas, es concordante con la existente en regiones aledañas, la cuenca superior del río Santa Cruz y la media e inferior del Gallegos.A taphonomic database for guanaco (Lama guanicoe and choique (Pterocnemia pennata is presented. It was created from environmental impact assessments carried out in the Middle Coyle Basin, Argentinean southern Patagonia. Information is presented according to landscape units, corresponding to terraces and valley bottoms. They are suitable as spatial units and for the generation of taphonomic expectations. Superimposition and potential mixing of archaeological artefacts and bones deposited naturally are discussed. Different taphonomic variables for guanaco and choique are analyzed by landscape unit, and the information obtained is compared. Results show that under

  17. Timing and Structure of Glacial Fluctuations at the end of the Last Ice Age in SW Patagonia

    Science.gov (United States)

    Kaplan, M. R.; Moreno, P. I.; Villa-Martínez, R. P.; Kubik, P. W.

    2006-12-01

    In the mid to high southern latitudes much of the controversy regarding synchrony or bipolar asynchrony has centered on late glacial time, especially in South America as it is one of the few land masses south of 45°S, outside Antarctica. To help resolve this controversy, and in general understand this important time interval, we studied in detail the timing, structure, and relative amplitude of climate changes during the late glacial period at 50°S in SW Patagonia. We combined two independent dating approaches including cosmogenic dating of moraines and radiocarbon of lake sediment cores, in addition to paleoecologic studies of key sections. We measured the 10Be concentrations in erratics from maximum and retreat glacial deposits from the Lago Nordenskjöld and Río Paine ice lobes. The 10Be ages from the two areas indicate a maximum extent prior to ~13 ka (4 ages), followed by slightly less extensive but sustained ice until ~12-11±1 ka. Excluding ages from deposits clearly related to retreat, the mean 10Be age for the two lobes falls between 13-12 ka, and the maximum ages from the two areas are 14.3±1.1 and 13.8±1.8 ka, respectively. This timing agrees well with minimum 14C ages for glacial geomorphic features associated with the maximum and retreat ice positions. We interpret the onset of organic sedimentation in the area occupied by a former ice-dammed lake at 12.6 cal ka as the closest minimum age for ice recession from the maximum ice extent. The pollen data indicate extreme cold conditions between 14.8-12.5 ka, slight amelioration between 12.5-10.9 ka, followed by warming in the early Holocene Period. We conclude that 1) a major cold reversal took place in SW Patagonia overlapping in time with the Antarctic Cold Reversal and 2) ice retreated slowly but lingered close to the maximum position throughout Younger Dryas time until ~10.7±0.9 ka under cold and, possibly, wet conditions. We speculate that southern latitude air- ocean dynamics, such as that of

  18. 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

  19. Cambios en lagos y circulación fluvial vinculados al calentamiento climático del Pleistoceno tardío-Holoceno temprano en Patagonia e isla 25 de mayo, islas Shetland del Sur, Antártida Changes in lakes and fluvial circulationlinked to climate warming in Late Pleistocene - Early Holocene in Patagonia and 25 de Mayo Island, Shetland del Sur Islands, Antarctica

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    R.A. del Valle

    2007-12-01

    Full Text Available El calentamiento clim ático que afectó a la Patagonia en el Pleistoceno tardío-Holoceno temprano produjo cambios en la morfología del paisaje, incluyendo la génesis, desarrollo y desintegración de grandes lagos al este de los Andes. Hasta entonces, los glaciares y sus morenas formaban diques naturales que embalsaron las aguas de deshielo y mantenían alto el nivel de las aguas en los grandes paleolagos. Posteriormente, la migración hacia el sur de la mejoría climática ocasionó la progresiva fusión del campo de hielo regional, y las morenas fueron cortadas por la erosión fluvial, cuando el calentamiento climático impactó plenamente en la región. El proceso afectó a la región de norte a sur en tiempos diferentes: 1 hace c. 13.200 años en el norte, 2 durante la transición Pleistoceno/Holoceno en la parte central, y 3 finalmente, en Tierra del Fuego hace unos 7.800 años. El rápido retroceso de los glaciares produjo el desalojo de los valles andinos a ambos lados de la cordillera, lo cual abrió cauces fluviales que atraviesan la cordillera desde entonces, inaugurando el drenaje hacia el océano Pacífico de grandes lagos glaciales que existían al oriente de los Andes. Esto resultó en el rápido descenso del nivel de los paleolagos. Un proceso similar ocurrió en las islas Shetland del Sur (Antártida hace unos 6.000 años.The climate warming that affected Patagonia region during late Pleistocene-early Holocene times produced changes in landscape morphology, including the formation, development, breakdown and disintegration of big lakes at the eastern side of Andes. Before these times, glaciers and their moraines formed natural dams that maintained a high water level in large paleolakes. The subsequent southward migration of climate amelioration produced the melting of the regional ice field, and moraines were cut by fluvial erosion, when climate warming strongly impacted in the region. The process occurred in the region from

  20. Proyecto de Plaza-Embarcadero en Caleta Tortel, Región de Aysén, Patagonia de Chile / Embarcadero Plaza-Project in Tortel, Region of Aysen Patagonia, Chile.

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    Medel Santibáñez, Paulina Andrea

    2007-06-01

    Full Text Available El proyecto de Título de Arquitectura, 2007, que se presenta tiene como objetivo central dar respuesta a necesidades reales, preservando y cuidando del medio local, tanto natural como sociocultural, dentro de la dinámica actual de cambios y apertura. Se reconoce los atributos y potencialidades propios de Caleta Tortel para preservar su identidad cultural y patrimonial a través de la consideración de la relación con su entorno, específicamente, reconociendo el vínculo entre la localidad y el mar como medio elemental que le da origen y permite su desarrollo. La “Plaza-Embarcadero" en Caleta Tortel es un conjunto de carácter público, de escala comunal y con un programa comunitario integrador y abierto para la interacción diaria y directa de los habitantes y visitantes.This work leading to the professional degree in architecture is an answer to certain needs of Caleta Tortel in the Chilean Patagonia, adapting itself to the local environment –social and natural- and to the changes of globalization. The core idea of this project is to preserve the spatial and economic link between the town and the sea. The proposed wharf is a meeting point for the neighbours and tourists.

  1. Survival, growth and vulnerability to drought in fire refuges: implications for the persistence of a fire-sensitive conifer in northern Patagonia.

    Science.gov (United States)

    Landesmann, Jennifer B; Gowda, Juan H; Garibaldi, Lucas A; Kitzberger, Thomas

    2015-12-01

    Fire severity and extent are expected to increase in many regions worldwide due to climate change. Therefore, it is crucial to assess the relative importance of deterministic vs. stochastic factors producing remnant vegetation to understand their function in the persistence of fire-sensitive plants. Vegetation remnants (areas within the landscape that have not burned for a considerable amount of time) may occur stochastically or in more predictable locations (fire refuges) where physical conditions decrease fire severity. Our aim was to determine if remnant forests of the fire-sensitive conifer Austrocedrus chilensis are associated with biophysical attributes that allow persistence in a fire-prone Patagonian landscape. We conducted a multi-scale approach, determining attributes of forest remnants and their surroundings (matrices) through remote sensing and field-based biophysical and functional characteristics, and quantifying how tree survival probability relates to microsite conditions. Trees within remnants displayed abundant fire scars, were twofold older and had threefold larger growth rates than matrix trees. Remnants were associated with high rocky cover and elevated topographical positions. Tree survival increased in hilltops, eastern aspects, and with sparse vegetation. Trees within remnants experienced severe reductions in growth during droughts. Our results suggest that A. chilensis remnants are mainly the result of refuges, where environmental conditions increase fire survival, but also increase susceptibility to drought. A trade-off between fire survival and drought vulnerability may imply that under increasing drought and fire severity, locations that in the past have served as refuges may reduce their ability to allow the persistence of fire-sensitive taxa. PMID:26334864

  2. Autolysis at the disintegrin domain of patagonfibrase, a metalloproteinase from Philodryas patagoniensis (Patagonia Green Racer; Dipsadidae) venom.

    Science.gov (United States)

    Peichoto, María E; Paes Leme, Adriana F; Pauletti, Bianca A; Batista, Isabel Correia; Mackessy, Stephen P; Acosta, Ofelia; Santoro, Marcelo L

    2010-09-01

    Patagonfibrase is a 57.5-kDa hemorrhagic metalloproteinase isolated from the venom of Philodryas patagoniensis (Patagonia Green Racer), a South American rear-fanged snake. Herein we demonstrate that patagonfibrase undergoes autolysis at its pH optimum (7.5) and at 37 degrees C, primarily producing a approximately 32.6 kDa fragment composed of disintegrin-like and cysteine-rich domains, as identified by mass spectrometry and N-terminal sequencing. The autolysis site for production of this fragment is similar to that observed for metalloproteinases from front-fanged Viperidae snake venoms. In the presence of Ca(2+), patagonfibrase was only partially autolysed, giving rise mainly to one fragment of approximately 52.2 kDa. In addition, calcium markedly enhanced the azocaseinolytic activity of patagonfibrase. Our findings contribute to the understanding of the structural and mechanistic bases of this family of metalloenzymes that are widely distributed among snake venoms, demonstrating that important post-translational modifications such as proteolysis can also contribute to the diversity and complexity of proteins found in rear-fanged snake venoms. PMID:20538077

  3. 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

  4. 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.

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

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    Guido Galafassi

    2014-06-01

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

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

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    Cretton, M.

    2016-03-01

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

  7. 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.

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

    Directory of Open Access Journals (Sweden)

    Victor Tafur

    2011-10-01

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

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

    International Nuclear Information System (INIS)

    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 μg g-1 dry wt.) were observed in P. columbina during winter, and maximum levels of Pb (0.82 μg g-1 dry wt.) were detected in Ulva sp. during summer. Legislative and health safety aspects were evaluated for Cd and Pb

  10. 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.

  11. Gelidivirgula Patagoniensis Gen. Nov., Sp. Nov., A Novel Psychrotolerant, Sporeforming Anaerobe Isolated from Magellanic Penguin Guano in Patagonia, Chile

    Science.gov (United States)

    Pikuta, Elena V.; Hoover, Richard B.; Marsic, Damien; Whitman, William B.; Tang, Jane; Krader, Paul

    2003-01-01

    A novel obligately anaerobic, psychrotrophic bacterium, strain PPP2(sup T), was isolated from guano of the Magellanic penguin (Spheniscus magellanicus) in Patagonia, Chile. The Gram-positive, sporeforming, straight rods with sizes 0.6-0.9 x 3.0-5.0 microns, are motile by peritrichous flagella. Growth was observed to occur within the pH range 6.0-9.5 (optimum pH x), and temperature range 2-28 C (optimum 20 C). The novel isolate does not require NaCl for growth, but is halotolerant and growth was observed between 0 and 7 % NaCl (w/v) with optimum at 0.5 % (w/v). The new isolate is a catalase negative chemoorganohetherotroph with fermentative metabolism and uses as substrates: peptone, Bacto-tryptone, Casamino acids, and yeast extract. The major metabolic products are: acetate, butyrate, ethanol, and hydrogen is a minor gas product.. Strain PPP2 was sensitive to ampicillin, tetracycline, chloramphenicol, rifampin, kanamycin, and gentamycin. The G+C content of the DNA is 43.6 mol%. On the basis of 16S rDNA gene sequences and phenotypic characteristics, it is proposed that the strain PPP2(sup T) (= ATCC BAA-755(sup T) = JSM ...(sup T)) is assigned to the new genus Gelidivirgula gen. nov., as a representative of the new species, Gelidivirgula patagonensis sp. nov.

  12. Differential use of the Argentine shelf by wintering adults and juveniles southern giant petrels, Macronectes giganteus, from Patagonia

    Science.gov (United States)

    Blanco, Gabriela S.; Quintana, Flavio

    2014-08-01

    To study habitat use and at-sea movements of southern giant petrels (SGP) during non-breeding period, we deployed 15 satellite transmitters (six adults, nine juveniles) at Isla Arce and Isla Gran Robredo colonies in Patagonia, Argentina. Birds were instrumented during 81.4 ± 37 days. Adult birds used 74% of the Argentine shelf concentrating mainly at the shelf break, middle shelf waters, and the surroundings of the colony. After fledging, juveniles spread to the Argentine, Uruguayan and Brazilian shelves within the South Atlantic. Adults alternated at-sea excursions (12 ± 5 days) with periods at the colony of 3 ± 0.3 days. Contrarily, juveniles moved first to the shelf break and then traveled northwards reaching the south of Brazil. There was some spatial overlap between age classes, but only during the first 30 days after juveniles had fledged; thereafter there was not overlap between the areas used by both age classes. The Argentine shelf is widely used by different species offering a suitable environment for foraging; this may be why adults SGP from Patagonian colonies spend all year-round within the Argentine shelf. The identification of used areas of non-breeding SGP fills a gap in the species knowledge contributing not only to the preservation the species, but also to the management of marine areas globally recognized as important for many other Procellariiformes.

  13. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Complex bioclimatic and soil gradients shape leaf trait variation in Embothrium coccineum (Proteaceae) among austral forests in Patagonia Gradientes bioclimáticos y edáficos modelan la variación en caracteres foliares de Embothrium coccineum (Proteaceae) en los bosques australes de la Patagonia

    OpenAIRE

    CINTIA P SOUTO; Premoli, Andrea C.; Reich, Peter B.

    2009-01-01

    Patterns of trait variation may be adaptive when vary in relation to an environmental gradient. In particular, leaf traits can affect productivity and competitive ability. We identify patterns of leaf size and shape variation with environmental heterogeneity in one of the most widespread tree species within temperate South America: Embothrium coccineum (Proteaceae). We collected leaf specimens and composite soil samples from 35 populations between 38° and 55° S latitude in Patagonia, covering...

  16. 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...

  17. Cenozoic back-arc magmatism of the southern extra-Andean Patagonia (44° 30' - 52° S: A review of geochemical data and geodynamic interpretations Magmatismo de retroarco cenozoico de la Patagonia extra-andina austral (44° 30' - 52° S: Una revisión de los datos geoquímicos e interpretaciones geodinámicas

    Directory of Open Access Journals (Sweden)

    M. D'Orazio

    2004-12-01

    Full Text Available Huge amounts of basaltic s.l. lavas were persistently erupted along the eastern side of the Andean Cordillera, throughout Cenozoic time, forming extensive plateaus, hundreds of monogenetic scoria cones and other volcanic structures in a continental back-arc setting. The igneous products exposed in the southern sector of the extra-Andean Patagonia (44° 30' - 52° S are dominantly mafic with minor slightly evolved compositions and rare highly differentiated products. The many published chemical analyses of these rocks, indicate that the mafic lavas range from strongly silica - undersaturated basanites to oversaturated basaltic andesites, and that most of the lavas have a typical within-plate geochemical signature. However, a number of lavas, generally erupted in the western-central sectors of Patagonia, are characterized by different distributions of the incompatible elements with high LILE/HFSE and LREE/HFSE ratios. The REE distribution modelling suggests a low degree of melting of a deep (> 70 km garnet-bearing source for the alkaline magmas, and a higher degree of melting of the same source, or an even higher degree of melting of an enriched source, for the subalkaline magmas. The available Sr-Nd-Pb isotope compositions clearly attest to a major geographic variation: the southernmost lavas have lower 87Sr/86Sr and higher 143Nd/144Nd and 206Pb/204Pb ratios with respect to those erupted to the north. On the whole, the Sr-Nd-Pb isotope compositions of the southern Patagonia lavas fall within the typical range of within-plate continental magmas; in addition the Pb isotope ratios fall in the range of the Southern Hemisphere Dupal Pb isotope anomaly. The geochemical variations of the southern Patagonia lavas are discussed in terms of different geochemical components: depleted and enriched sub-slab asthenosphere, enriched continental lithospheric mantle, continental crust and subducted materials. The geodynamic significance is interpreted with in the

  18. 1990 Northern, Iran Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A magnitude 7.7 earthquake occurred in the Gilan Province between the towns of Rudbar and Manjil in northern Iran on Thursday, June 21, 1990 (June 20 at 21:00 GMT)....

  19. Northern blotting analysis

    DEFF Research Database (Denmark)

    Josefsen, Knud; Nielsen, Henrik

    2011-01-01

    Northern blotting analysis is a classical method for analysis of the size and steady-state level of a specific RNA in a complex sample. In short, the RNA is size-fractionated by gel electrophoresis and transferred by blotting onto a membrane to which the RNA is covalently bound. Then, the membrane...... closing the gap to the more laborious nuclease protection experiments....

  20. Aportes de los "intermediarios culturales" en la conformación de los paisajes fronterizos del norte de la patagonia a fines del siglo XVIII

    Directory of Open Access Journals (Sweden)

    Laura Aylén Enrique

    2012-12-01

    Full Text Available A fines del siglo XVIII la Corona española envió expedicionarios a reconocer el norte de la Patagonia, un territorio dominado por grupos indígenas pero de importancia estratégica para los hispanocriollos. Los funcionarios del Virreinato del Río de la Plata que llevaron a cabo dichas exploraciones registraron sus impresiones en diarios de viaje que analizamos con el objetivo de examinar los modos en que el paisaje norpatagónico fue construido simbólicamente. Consideramos que dicho paisaje se constituyó en base a las luchas desplegadas tanto por hispanocriollos como por indígenas buscando dar sentido al territorio. Sostenemos que, en este contexto, los personajes que se desempeñaban como intérpretes ejercían un rol fundamental en la configuración del territorio, dada la ambigüedad de su posición de intermediarios en las relaciones interétnicas.By late eighteen century the Spanish Crown sent expedition to recognize north Patagonia, a territory dominated by indigenous groups but also of strategic importance to the Hispanic-Creole population. River Plate Viceroyalty officials in charge of the above-mentioned explorations registered their impressions in travel diaries that are thoroughly analyzed in order to discover the ways this landscape of north Patagonia was symbolically constructed. We think this mestizo landscape was the result of struggles maintained between Hispanic-Creoles and natives searching to convey meaning to the territory. Moreover, we state that in this context, the actors who served as interpreters developed a key role in the territorial configuration, given the ambiguity of their position as intermediaries of interethnic relations.

  1. Aportes de los "intermediarios culturales" en la conformación de los paisajes fronterizos del norte de la patagonia a fines del siglo XVIII

    OpenAIRE

    Laura Aylén Enrique

    2012-01-01

    A fines del siglo XVIII la Corona española envió expedicionarios a reconocer el norte de la Patagonia, un territorio dominado por grupos indígenas pero de importancia estratégica para los hispanocriollos. Los funcionarios del Virreinato del Río de la Plata que llevaron a cabo dichas exploraciones registraron sus impresiones en diarios de viaje que analizamos con el objetivo de examinar los modos en que el paisaje norpatagónico fue construido simbólicamente. Consideramos que dicho paisaje se c...

  2. Proyecto Hidroaysén: capitalismo extractivista, regulación estatal y acción colectiva en la Patagonia

    OpenAIRE

    Reyes Herrera, Sonia; Rodríguez Torrent, Juan Carlos

    2015-01-01

    En este artículo entendemos que el eje de los conflictos ambientales en general, y en la Patagonia en particular, está definido por la forma específica de producción del territorio. Es decir, sobre el uso de los activos naturales, las relaciones que se establecen con la naturaleza, las formas de gobernar estos territorios (actores) y cuál es la relación que mantienen con otros. La emergencia de este tipo de conflictos se explica por la expansión del capitalismo extractivista en zonas de front...

  3. OBSERVATORIO DE LAS TECNOLOGÍAS EN LA EDUCACIÓN EN LA PATAGONIA: EL PROCESO DE ELABORACIÓN Y SELECCIÓN DE INDICADORES.

    OpenAIRE

    Silvia Gonzalez; Victoria Marín; Jesús Salinas

    2013-01-01

    Este trabajo describe el proceso de elaboración de un conjunto de indicadores aplicando la técnica Delphi. Con esos indicadores el Observatorio de las Tecnologías en la Educación en la Patagonia, con la finalidad de orientar políticas educativas que tiendan a promover la inclusión digital, estudiará el acceso y uso de las TIC para producir y difundir información oportuna, actualizada, relevante y académicamente confiable. La investigación se realiza en el marco del Proyecto D/030419/10 Implan...

  4. 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

    Directory of Open Access Journals (Sweden)

    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

  5. 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...

  6. Petrology of continental pyroclastic and epiclastic sequences in the Chubut Group (Cretaceous): Los Altares-Las Plumas area, Chubut, Patagonia Argentina

    OpenAIRE

    Marcelo Manassero; Patricia E Zalba; Renato R. Andreis; Martín Morosi

    2000-01-01

    La petrología de secuencias piroclásticas y epiclásticas en el Grupo Chubut (Cretácico): área de Los Altares-Las Plumas, Patagonia Argentina. Las sucesiones volcaniclásticas de la Formación Cerro Barcino (Grupo Chubut, Aptiano-Cenomaniano), afloran en ambas márgenes del río Chubut con 200 m de espesor. Los miembros medio: Cerro Castaño (sineruptivo, 90 m) y superior, Las Plumas (intereruptivo, 110 m) son descritos con el mapeo fotogeológico, estudios de campo y laboratorio (mineralógico, petr...

  7. Producción local de cuentas de valva en el bosque del noroeste de Patagonia : Una aproximación desde la arqueología experimental

    OpenAIRE

    Leonardt, Sabrina

    2014-01-01

    En numerosos sitios tardíos del noroeste de Patagonia es frecuente el registro de cuentas y restos de valvas, principalmente del molusco de agua dulce Diplodon chilensis. Estos últimos suelen interpretarse como resultado de su consumo alimenticio. En este trabajo se evalúa la posibilidad de que estos restos sean evidencia de la producción local de cuentas. A partir del desarrollo de un programa de arqueología experimental se define un patrón de desechos de manufactura esperables en contextos ...

  8. Estudio de las modificaciones postdepositacionales de la superficie ósea en una muestra de entierros humanos de Patagonia centro-meridional

    OpenAIRE

    Del Papa, Mariano C.

    2001-01-01

    La adecuada interpretación de los patrones observados en la distribución sexual, etárea y cronológica de los indicadores biológicos considerados en los estudios bioarqueológicos depende, en gran medida, del conocimiento de la historia tafonómica y postdepositacional de las muestras utilizadas. Sin embargo, con frecuencia este es un aspecto poco tratado en este tipo de estudios. Como un medio establecer la comparabilidad entre muestras provenientes de distintos sectores de Patagonia Centro-Mer...

  9. Contribución al conocimiento de los hemeróbidos de Patagonia y Tierra del Fuego (Insecta, Neuroptera, Hemerobiidae)

    OpenAIRE

    Monserrat, Víctor J.

    2003-01-01

    New data on the biology and distribution of 10 species of brown-lacewings collected in 48 localities of Patagonia and Tierra del Fuego are given. Larvae of Hemerobius bolivari Banks, 1910, Hemerobius chilensis Nakahara, 1965, Hemerobius stenopterus Monserrat, 1996, Sympherobius gayi Navás, 1910, Nomerobius cuspidatus Oswald, 1990 and Gayomyia falcata (Blanchard in Gay, 1851) are d...

  10. 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...

  11. Caracterización de tres cepas bacterianas capaces de fijar nitrógeno y biodegradar hidrocarburos aisladas de un suelo de la Patagonia

    OpenAIRE

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

    2010-01-01

    El objetivo de este trabajo fue caracterizar tres microorganismos capaces de biodegradar hidrocarburos en ausencia de nitrógeno aislados a partir de un suelo de la Patagonia con una larga historia de contaminación por petróleo y sus derivados. Para ello se aislaron tres cepas bacterianas de un suelo patagónico con baja concentración de nitrógeno y contaminado con hidrocarburos. Estos fueron identificados por ARNr 16S y ácidos grasos de membrana. También se estudiaron sus perfiles de biodegrad...

  12. Memorias Silenciadas y patrimonios ausentes en el Museo Histórico de El Hoyo, Comarca Andina del Paralelo 42, Patagonia Argentina

    Directory of Open Access Journals (Sweden)

    CAROLINA CRESPO

    2014-08-01

    Full Text Available This article analyzes the silences and absent heritage in the exhibition at the Historical Museum in the town of El Hoyo in Patagonia (Argentina. In particular, it examines the widespread silences about indigenous peoples and certain issues and relationships, while attempting to reveal the mechanisms by which the institution gave shape to these absences. We approach the analysis of these silencings as productive resources through which systems of belonging and differentiation, stratification and territorialization, are configured and transmitted, revealing relations of power and structuring the possible field of action.

  13. Isótopos estables, análisis arqueofaunísticos y entierros humanos en la costa centro-norte de Patagonia

    OpenAIRE

    Gómez Otero, Julieta

    2001-01-01

    Investigaciones arqueológicas realizadas en la costa centro-norte de Patagonia demostraron la presencia humana desde el 4370 A.P. Entre los diversos estudios, se realizaron análisis de isótopos estables a doce esqueletos humanos datados, de los cuáles diez se hallaron en esa porción de la costa atlántica. Si bien los resultados indican una alta variabilidad intersitio y ausencia de tendencias temporales, también señalan que los recursos terrestres, en especial guanacos, otros animales y plant...

  14. De aquí para allá, sin o con caballo. Patagonia, 13.000 años de historia

    OpenAIRE

    Mameli, Laura

    2013-01-01

    A lo largo de 13.000 años Patagonia estuvo ocupada por poblaciones cazadorasrecolectoras sumamente móviles, con diversificada movilidad territorial, residencial y logística. Las complejas y extensas redes sociales que constituyeron permitieron la circulación de bienes, personas e ideas, condicionando los procesos de etnogénesis y los mecanismos de fisión y fusión social. A fines del Holoceno, la naturaleza de los desplazamientos nómadas y nuevas formas de interacción social y contacto provoca...

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Northern pipelines : backgrounder

    International Nuclear Information System (INIS)

    Most analysts agree that demand for natural gas in North America will continue to grow. Favourable market conditions created by rising demand and declining production have sparked renewed interest in northern natural gas development. The 2002 Annual Energy Outlook forecasted U.S. consumption to increase at an annual average rate of 2 per cent from 22.8 trillion cubic feet to 33.8 TCF by 2020, mostly due to rapid growth in demand for electric power generation. Natural gas prices are also expected to increase at an annual average rate of 1.6 per cent, reaching $3.26 per thousand cubic feet in 2020. There are currently 3 proposals for pipelines to move northern gas to US markets. They include a stand-alone Mackenzie Delta Project, the Alaska Highway Pipeline Project, and an offshore route that would combine Alaskan and Canadian gas in a pipeline across the floor of the Beaufort Sea. Current market conditions and demand suggest that the projects are not mutually exclusive, but complimentary. The factors that differentiate northern pipeline proposals are reserves, preparedness for market, costs, engineering, and environmental differences. Canada has affirmed its role to provide the regulatory and fiscal certainty needed by industry to make investment decisions. The Government of the Yukon does not believe that the Alaska Highway Project will shut in Mackenzie Delta gas, but will instead pave the way for development of a new northern natural gas industry. The Alaska Highway Pipeline Project will bring significant benefits for the Yukon, the Northwest Territories and the rest of Canada. Unresolved land claims are one of the challenges that has to be addressed for both Yukon and the Northwest Territories, as the proposed Alaska Highway Pipeline will travel through traditional territories of several Yukon first Nations. 1 tab., 4 figs

  17. 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

  18. Is the prominent ericoid mycorrhizal fungus Rhizoscyphus ericae absent in the Southern Hemisphere’s Ericaceae? A case study on the diversity of root mycobionts in Gaultheria spp. from northwest Patagonia, Argentina

    Czech Academy of Sciences Publication Activity Database

    Brusone, M. C.; Fontenla, S. B.; Vohník, Martin

    2015-01-01

    Roč. 25, č. 1 (2015), s. 25-40. ISSN 0940-6360 R&D Projects: GA MŠk 7AMB12AR014 Institutional support: RVO:67985939 Keywords : ericoid mycorrhiza * Gaultheria * Patagonia Subject RIV: EF - Botanics Impact factor: 3.459, year: 2014

  19. Titanium and oxygen isotope diffusion in quartz-phenocrysts from a Jurassic rhyolite, Chon Aike Province (Fitz Roy, Patagonia)

    Science.gov (United States)

    Seitz, S.; Putlitz, B.; Baumgartner, L. P.; Escrig, S.; Meibom, A.; Leresche, S.; Vennemann, T. W.

    2014-12-01

    The volcanic El Quemado Complex was deposited during the breakup of Gondwana during the Middle and Late Jurassic. It is part of a large silicic igneous province, which includes the Chon Aike Province in Southern Patagonia and related rocks from the Antarctic Peninsula [1]. The Complex consists of rhyolitic and dacitic ignimbrites and air-fall tuffs, intercalated with andesitic to rhyolitic lava flows. New LA-ICPMS U/Pb-dates of zircons from the Fitz Roy area yield ages between 148 and 153Ma. No inherited zircons were found, suggesting that the temperature of 850°C calculated from zircon saturation is a minimum temperature. Lava flows are typically rich in quartz phenocrysts, which preserved magmatic trace element zoning, as revealed by cathodoluminescence (CL): light cores are surrounded by several darker and lighter zones towards the rim. The δ18O-values for quartz of between 11 to 14 ‰ are compatible with a crustal source for the magma and the SIMS analyses of phenocrysts reveal no zoning in O-isotope compositions. High-resolution Ti-profiles were obtained by NanoSIMS with a beam size of ~200 nm and a minimum step size of ~120 nm. Several lines perpendicular to the magmatic zoning of the quartz-phenocrysts were measured. The profiles show sharp changes in the 48Ti/29Si-ratio over a distance of 5 μm, which correlate with CL-intensity changes. The profiles can be used for diffusion chronometry. The distances obtained from NanoSIMS profiles were used to calculate maximum diffusional relaxation times. Assuming a step function as initial condition and extrusion temperatures from zircon saturation of 850°C, we obtain a maximum residence time for the quartz-phenocrysts of 3.5 years. [1] Pankhurst R.J., Riley T.R., Fanning C.M., Kelley S.P., 2000. J. Pet., 41, 605-625.

  20. 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

  1. Trichococcus patagoniensis sp. nov., a facultative anaerobe that grows at -5 degrees C, isolated from penguin guano in Chilean Patagonia.

    Science.gov (United States)

    Pikuta, Elena V; Hoover, Richard B; Bej, Asim K; Marsic, Damien; Whitman, William B; Krader, Paul E; Tang, Jane

    2006-09-01

    A novel, extremely psychrotolerant, facultative anaerobe, strain PmagG1(T), was isolated from guano of Magellanic penguins (Spheniscus magellanicus) collected in Chilean Patagonia. Gram-variable, motile cocci with a diameter of 1.3-2.0 mum were observed singularly or in pairs, short chains and irregular conglomerates. Growth occurred within the pH range 6.0-10.0, with optimum growth at pH 8.5. The temperature range for growth of the novel isolate was from -5 to 35 degrees C, with optimum growth at 28-30 degrees C. Strain PmagG1(T) did not require NaCl, as growth was observed in the presence of 0-6.5 % NaCl with optimum growth at 0.5 % (w/v). Strain PmagG1(T) was a catalase-negative chemo-organoheterotroph that used sugars and some organic acids as substrates. The metabolic end products were lactate, formate, acetate, ethanol and CO(2). Strain PmagG1(T) was sensitive to ampicillin, tetracycline, chloramphenicol, rifampicin, kanamycin and gentamicin. The G+C content of its genomic DNA was 45.8 mol%. 16S rRNA gene sequence analysis showed 100 % similarity of strain PmagG1(T) with Trichococcus collinsii ATCC BAA-296(T), but DNA-DNA hybridization between them demonstrated relatedness values of <45+/-1 %. Another phylogenetically closely related species, Trichococcus pasteurii, showed 99.85 % similarity by 16S rRNA sequencing and DNA-DNA hybridization showed relatedness values of 47+/-1.5 %. Based on genotypic and phenotypic characteristics, the novel species Trichococcus patagoniensis sp. nov. is proposed, with strain PmagG1(T) (=ATCC BAA-756(T)=JCM 12176(T)=CIP 108035(T)) as the type strain. PMID:16957099

  2. Trichococcus Patagoniensis sp. nov., a Facultative Anaerobe that grows at -5 C, Isolated from Penguin Guano in Chilean Patagonia

    Science.gov (United States)

    Pikuta, Elena V.; Hoover, Richard B.; Bej, Asim K.; Marsic, Damien; Whitman, William B.; Krader, Paul E.; Tang, Jane

    2006-01-01

    A novel, extremely psychrotolerant, facultative anaerobe, strain PmagGl(sup T), was isolated from guano of Magellanic penguins (Spheniscus magellanicus) collected in Chilean Patagonia. Gram-variable, motile cocci with a diameter of 1.3-2.0 micrometers were observed singularly or in pairs, short chains and irregular conglomerates. Growth occurred within the pH range 6.0-10.0, with optimum growth at pH 8.5. The temperature range for growth of the novel isolate was from -5 to 35 C, with optimum growth at 28-30 C. Strain PmagG1(sup T) did not require NaCl, as growth was observed in the presence of 0-6.5% NaCl with optimum growth at 0.5% (w/v). Strain PmagGl(sup T) was a catalase-negative chemo-organoheterotroph that used sugars and some organic acids as substrates. The metabolic end products were lactate, formate, acetate, ethanol and Con. Strain PmagG1(sup T) was sensitive to ampicillin, tetracycline, chloramphenicol, rifampicin, kanamycin and gentamicin. The G+C content of its genomic DNA was 45.8 mol%. 16S rRNA gene sequence analysis showed 100 % similarity of strain PmagG1(sup T) with Trichococcus collinsii ATCC BAA-296(sup T), but DNA-DNA hybridization between them demonstrated relatedness values of less than 45 plus or minus 1%. Another phylogenetically closely related species, Trichococcus pasteurii, showed 99.85 % similarity by 16s rRNA sequencing and DNA-DNA hybridization showed relatedness values of 47 plus or minus 1.5%. Based on genotypic and phenotypic characteristics, the novel species Trichococcus patagoniensis sp. nov. is proposed, with strain PmagG1(sup T) (=ATCC BAA-756(sup T)=JCM 12176(sup T)=CIP 108035(sup T)) as the type strain.

  3. Climate-driven terrestrial inputs in ultraoligotrophic mountain streams of Andean Patagonia revealed through chromophoric and fluorescent dissolved organic matter.

    Science.gov (United States)

    Garcia, Roberto D; Reissig, Mariana; Queimaliños, Claudia P; Garcia, Patricia E; Dieguez, Maria C

    2015-07-15

    Fluvial networks transport a substantial fraction of the terrestrial production, contributing to the global carbon cycle and being shaped by hydrologic, natural and anthropogenic factors. In this investigation, four Andean Patagonian oligotrophic streams connecting a forested catchment (~125km(2)) and draining to a double-basin large and deep lake (Lake Moreno complex, Northwestern Patagonia), were surveyed to analyze the dynamics of the allochthonous subsidy. The results of a 30month survey showed that the catchment supplies nutrients and dissolved organic matter (DOM) to the streams. The eruption of the Puyehue-Cordón Caulle at the beginning of the study overlapped with seasonal precipitation events. The largest terrestrial input was timed with precipitation which increased particulate materials, nutrients and DOM through enhanced runoff. Baseline suspended solids and nutrients were very low in all the streams (suspended solids: ~1mg/L; total nitrogen: ~0.02mg/L; total phosphorus: ~5μg/L), increasing several fold with runoff. Baseline dissolved organic carbon concentrations (DOC) ranged between 0.15 and 1mg/L peaking up to three-fold. Chromophoric and fluorescent analyses characterized the DOM as of large molecular weight and high aromaticity. Parallel factor modeling (PARAFAC) of DOM fluorescence matrices revealed three components of terrestrial origin, with certain degree of microbial processing: C1 and C2 (terrestrial humic-like compounds) and C3 (protein-like and pigment derived compounds). Seasonal changes in MOD quality represent different breakdown stages of the allochthonous DOM. Our survey allowed us to record and discuss the effects of the Puyehue-Cordón Caulle eruption, showing that due to the high slopes, high current and discharge of the streams the volcanic material was rapidly exported to the Moreno Lake complex. Overall, this survey underscores the magnitude and timing of the allochthonous input revealing the terrestrial subsidy to food webs in

  4. Serosurvey for selected infectious agents in two sympatric species of cormorants (Phalacrocorax atriceps and Phalacrocorax magellanicus) from coastal Patagonia, Argentina.

    Science.gov (United States)

    Gallo, Luciana; Quintana, Flavio; Uhart, Marcela

    2013-07-01

    We conducted a serologic survey for selected infectious agents on two sympatric cormorants, the Imperial Cormorant (Phalacrocorax atriceps) and the Rock Shag (Phalacrocorax magellanicus). Blood was collected from 267 Imperial Cormorants and 106 Rock Shags at 17 colonies along the Patagonia Atlantic shore during nine breeding seasons (1994, 1999-2001-2005-2008-2010). Antibodies to four pathogens were common to both species and frequently observed: avian paramyxovirus type 1 (56% of Imperial Cormorants and 56% of Rock Shags); avian adenovirus (67% of Imperial Cormorants and 40% of Rock Shags); infectious bronchitis virus serotypes IBV-41, IBV-46, IBV-99, and IBV-JMK (53% of Imperial Cormorants and 64% of Rock Shags); and Salmonella pullorum (18% of Imperial Cormorants and 7% of Rock Shags). Antibody prevalence for these pathogens varied significantly between species, except for avian paramyxovirus type 1. Exposure to avian paramyxovirus type 1 and all serotypes of infectious bronchitis virus varied significantly among seasons in both species. In contrast, the sporadic occurrence of positive titers suggest that cormorants had occasional exposure to Aspergillus spp. (3% of Rock Shags, only in 2000), avian paramyxovirus type 3 (5% of Rock Shags, only in 2008), Chlamydophila spp. (1% of Imperial Cormorants, only in 2010), and avian reovirus (1% of Rock Shags, only in 1999; 29% of Imperial Cormorants, in 2008 and 2010). Both species were antibody negative for avian encephalomyelitis virus, avian influenza virus, avian laryngotracheitis virus, avian paramyxovirus type 2, and infectious bursal disease virus. We provide the first information on pathogen exposure, indicated by detection of antibody in blood samples, for two sympatric species of South Atlantic cormorants. To determine major causes of morbidity and mortality in these birds future efforts should focus on necropsy surveys in cormorant colonies. PMID:23778597

  5. 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.

  6. 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.

  7. 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.

  8. Presence of Arctotherium (Carnivora, Ursidae, Tremarctinae in a pre-cultural level of Baño Nuevo-1 cave (Central Patagonia, Chile

    Directory of Open Access Journals (Sweden)

    López Mendoza, P.

    2015-12-01

    Full Text Available The description of an I3 assigned to Arctotherium sp. obtained from the Baño Nuevo-1 site (Central Patagonia, Chile is presented. The finding was recovered from Layer 5 and it is associated to Macrauchenia sp., Lama guanicoe, Felidae, Camelidae, Equidae and Mylodontidae, within a sterile deposit of cultural material, dated between ca. 13.500 and 11.200 BP. Despite the fact that it is only a single specimen, such finding extends the known distribution for the genus in Chile.Se presenta la descripción de un I3 asignado a Arctotherium sp. proveniente del sitio Baño Nuevo-1 (Patagonia Central, Chile. El hallazgo fue realizado en la Capa 5 y está asociado a restos de Macrauchenia sp., Lama guanicoe, Felidae, Camelidae, Equidae y Mylodontidae dentro de un depósito estéril de material cultural, datado entre los ca. 13.500 y 11.200 años AP. Aunque se trata de un único espécimen, amplía el rango de distribución conocido para este género en Chile.

  9. Petrological features of suprasubuction mantle: evidence from northern, central and southern Patagonian mantle xenoliths

    Science.gov (United States)

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

    2012-04-01

    Patagonia has a number of outcrops where xenoliths-bearing lavas can be found. It thus represents a good opportunity to study mantle material in supra-subduction environment both on arc and back-arc position, from as near as 300 km to as far as 600 km from the Chile trench. A wealth of data is nowadays available on these xenoliths, starting from petrographic observations, whole-rock and mineral major and trace element analyses plus few isotopic analyses on whole rock and mineral separates. To this already large dataset the petrological features of another locality (Estancia Sol de Mayo, ESM) were added, allowing a comparison between as much as eight localities coming from northern (Cerro Aznare, Praguaniyeu, Cerro Rio Chubut, Cerro de los Chenques), central (Cerro Clark and Gobernador Gregores) and southern Patagonia (Pali Aike), covering approximately an area of 1000 x 300 km. Most xenoliths are harzburgites, with minor amount of lherzolites, wehrlites and dunites. In the Al2O3 vs mg# [MgO/(MgO+FeO) mol %] diagram clinopyroxene (cpx) compositions highlight three different trends, with orthopyroxene (opx) compositions plotting on two of these. In the first trend Al2O3 content increases at almost constant mg# mol % (trend 1). The second trend comprises only cpx from wehrlites (trend 2) and is situated between the first and the third trend. In the third trend the slight increases of Al2O3 is associated with a remarkable decrease in mg# (trend 3). LREE and LILE abundances in cpx from Tres Lagos and Cerro Rio Chubut are directly correlated to the Al2O3, while they are inversely correlated at Cerro de Los Chenques and Cerro Fraile. In the first case it is likely that a metasomatic process affects the mantle domains beneath those areas, while in the second case a refertilization event caused by a tholeiitic melt is favorite. In other cases, as for Gobernador Gregores, a more complex situation is recorded, with two groups of samples showing both negative and positive

  10. Northern Pintail Telemetry [ds231

    Data.gov (United States)

    California Department of Resources — Using radio-telemetry, female northern pintail (Anas acuta) survival, distribution, and movements during late August-March in Central California were determined...

  11. 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

  12. Sapling growth and crown expansion in canopy gaps of Nothofagus pumilio (lenga) forests in Chubut, Patagonia, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Bernal, P. M.; Defosse, G. E.; Quinteros, C. P.; Bava, J. O.

    2012-07-01

    In the province of Chubut in Patagonia, Argentina, Nothofagus pumilio forests (locally known as lenga), are managed through selective cuts, which imply the opening of canopy gaps. This management scheme is carried out without taking into consideration the changes of sapling requirements through either a cutting cycle or the precipitation gradient in which these forests thrive. To analyze these changes, we inferred the facilitation-competition balance between the canopy and regeneration, studying the effects of precipitation levels, gap size and gap age on saplings growth in height on 45 canopy gaps artificially created between 1960 and 1993. Results showed that during the first 20 years since gap opening, growth of regeneration is determined by light availability in mesic sites and by water availability in xeric sites. However, differences due to precipitation levels gradually decrease over time. Moreover, in the period between 20 and 35 years after gap opening, in both mesic and xeric sites, growth is limited by light availability. This indicates that in xeric sites, sapling growth requirements shift from a water-dependent situation to a light-dependent situation. The average closing rate of gaps due to lateral growth of bordering trees is high enough so that within the proposed gap size range, gap healing can occur before regeneration reaches the upper stratum. Consequently, in mesic sites gap opening can be done by a single operation that generates gaps with diameters of approximately twice the average height of the canopy (D/H). While in xeric environments, lenga seedling establishment and initial growth require the cover of small gaps, but advanced regeneration requires bigger gaps to reach the canopy. For this reason, gaps should be opened in two stages: the first gaps should be opened with a D/H between 0.8 and 1, and after a cutting cycle of 35 years, these openings should be enlarged to a D/H between 1.5 and 2. The close relationship maintained between the

  13. Paralytic shellfish poisoning: post-mortem analysis of tissue and body fluid samples from human victims in the Patagonia fjords.

    Science.gov (United States)

    García, Carlos; del Carmen Bravo, María; Lagos, Marcelo; Lagos, Néstor

    2004-02-01

    In July 5, 2002 fishermen working in harvesting sea urchin (Loxechinus albus) in the Patagonia Chilean fjords were intoxicated by consumption of filter-feeder bivalve Aulacomya ater. After the ingestion of 7-9 ribbed mussel, two fishermen died 3-4 h after shellfish consumption. The forensic examination in both victims did not show pathological abnormalities with the exception of the lungs conditions, crackling to the touch, pulmonary congestion and edema. The toxic mussel sample showed a toxicity measured by mouse bioassay of 8575 microg of STX (saxitoxin) equivalent by 100 g of shellfish meat. Using post-column derivatization HPLC method with fluorescent on line detection was possible to measure mass amount of each paralytic shellfish poisoning (PSP) toxin yielding individual toxin concentrations. These PSP toxins were identified in the gastric content, body fluids (urine, bile and cerebrospinal fluid) and tissue samples (liver, kidney, lung, stomach, spleen, heart, brain, adrenal glands, pancreas and thyroids glands). The toxin profiles of each body fluid and tissue samples and the amount of each PSP toxin detected are reported. The PSP toxins found in the gastric content, were STX and the gonyautoxins (GTX4, GTX1, GTX5, GTX3 and GTX2) which showed to be the major amount of PSP toxins found in the victims biological samples. The PSP toxin composition in urine and bile showed as major PSP toxins neoSaxitoxin (neoSTX) and GTX4/GTX1 epimers, both STX analogues with an hydroxyl group (-OH) in the N(1) of the tetrahydropurine nucleus. The neoSTX was not present in the gastric content sample, indicating that the oxidation of N(1) in the STX tetrahydropurine nucleus resulted neoSTX, in a similar way that GTX3/GTX2 epimers were transformed in GTX4/GTX1 epimers. Beside this metabolic transformation, also the hydrolysis of carbamoyl group from STX to form its decarbomoyl analogue decarbamoylsaxitoxin was detected in liver, kidney and lung. These two findings show that PSP

  14. A new fossil from the Jurassic of Patagonia reveals the early basicranial evolution and the origins of Crocodyliformes.

    Science.gov (United States)

    Pol, Diego; Rauhut, Oliver W M; Lecuona, Agustina; Leardi, Juan M; Xu, Xing; Clark, James M

    2013-11-01

    Extant crocodylians have a limited taxonomic and ecological diversity but they belong to a lineage (Crocodylomorpha) that includes basal and rather generalized species and a highly diverse clade, Crocodyliformes. The latter was among the most successful groups of Mesozoic tetrapods, both in terms of taxonomic and ecological diversity. Crocodyliforms thrived in terrestrial, semiaquatic, and marine environments, and their fossil diversity includes carnivorous, piscivorous, insectivorous, and herbivorous species. This remarkable ecological and trophic diversity is thought only to occur in forms with a completely akinetic skull, characterized by a functionally integrated and tightly sutured braincase-quadrate-palate complex. However, the patterns of evolutionary change that led to the highly modified skull of crocodyliforms and that likely enabled their diversification remain poorly understood. Herein, a new basal crocodylomorph from the Late Jurassic of Patagonia is described, Almadasuchus figarii gen. et sp. nov. The new taxon is known from a well-preserved posterior region of the skull as well as other craniomandibular and postcranial remains. Almadasuchus figarii differs from all other crocodylomorphs in the presence of six autapomorphic features, including the presence of a large lateral notch on the upper temporal bar, an otic shelf of the squamosal that is wider than long, a deep subtriangular concavity on the posterolateral surface of the squamosal, and an elongated pneumatopore on the ventral surface of the quadrate. Phylogenetic analysis focused on the origin of Crocodyliformes places Almadasuchus as the sister group of Crocodyliformes, supported by synapomorphic features of the skull (e.g. subtriangular basisphenoid, absence of basipterygoid process, absence of a sagittal ridge on the frontal, and a flat anterior skull roof with an ornamented dorsal surface). New braincase information provided by Almadasuchus and other crocodylomorphs indicates that most of

  15. 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

  16. 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

  17. 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

  18. 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...

  19. 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

    OpenAIRE

    Marien Béguelin; Gustavo Barrientos

    2006-01-01

    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 Tier...

  20. Hydrogen as a vector in Mercosul for the transmission of wind power from Patagonia and as a vehicle to its overseas exportation; Hidrogeno como vector en el Mercosur para transmision de energia eolica desde la Patagonia y como vehiculo para su exportacion a ultramar

    Energy Technology Data Exchange (ETDEWEB)

    Spinadel, Erico; Gracia Nunes, Sabas Luis; Gamallo, Florencio [Buenos Aires Univ. (Argentina). Facultad de Ingenieria. GENCo - Grupo de I y D en Energias No Convencionales

    1997-12-31

    The wind resource in Patagonia is one of the most important energetic reserves in Latin America, and should be taken into account in any high-scale generation project proposed for this area. However, the direct connection of wind farms to the net introduces some unstability problems that limit the amount of admissible wind power in it. The authors`s proposal is applying all the obtained wind energy to an electrolytic process for hydrogen production, for using it later as an alternative fuel in conventional power stations. (author) 8 refs.; e-mail: postmaster at genco.uba.ar

  1. 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...

  2. 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

    OpenAIRE

    GUILLERMO J MARTÍNEZ-PASTUR; MARÍA V LENCINAS; Peri, Pablo L.; Juan M. Cellini; ALICIA MORETTO

    2010-01-01

    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 manej...

  3. Environmental and climatic changes in Central Chilean Patagonia since the Late Glacial (Mallín El Embudo, 44° S

    Directory of Open Access Journals (Sweden)

    M. E. de Porras

    2013-10-01

    Full Text Available Multi-millennial environmental and climatic changes in Central Chilean Patagonia (44–49° S during the Last Glacial–Interglacial cycle have been of particular interest as changes in the position and strength of the Southern Westerlies are the major forcing factor conditioning the environmental dynamics. Recent attempts to reconstruct regional environmental and climatic signals from Central Chilean Patagonia reveal some discrepancies and unclear issues among the records. This paper presents the 13 ka pollen and charcoal records from Mallín El Embudo (44°40' S; 71°42' W located in the deciduous Nothofagus forest in the middle Río Cisnes valley. The paper aims to (1 establish the timing and magnitude of local vegetation changes and fire activity since the Late Glacial and (2 integrate these results at the regional scale in order to discuss the discrepancies and depict the Central Chilean Patagonia environmental and climatic dynamics since Late Glacial. Open landscapes dominated by grasses associated with scattered Nothofagus forest patches dominated middle Río Cisnes valley between 13–11.2 ka suggesting low effective moisture but also reflecting that landscape configuration after glacial retreat was still ongoing. At 11.2 ka, a sudden development of an open and quite dynamic Nothofagus forest probably associated to the synchronous high fire activity occurred suggesting a rise in effective moisture. Since 9.5 ka, the record reflects the presence of a closed Nothofagus forest related to higher/similar effective moisture conditions than before but under an unmarked precipitation seasonality. The forest experienced a slight canopy opening since 5.7 ka, probably due to slightly drier conditions than before followed by a sudden change around 4.2 ka associated with fire and volcanic disturbances. The recovery of an open Nothofagus forest related to slight wetter conditions (similar to present occurred around 2 ka and persisted under highly

  4. Fertilization in northern forests

    DEFF Research Database (Denmark)

    Hedwall, Per Ola; Gong, Peichen; Ingerslev, Morten;

    2014-01-01

    intensive fertilization regimens implying intensive fertilization starting in young forests may, on the other hand, considerably increase the biomass supply and value for the industry. The economic and environmental risks of this type of fertilization may, however, be larger and more research is needed on......Forests of northern ecosystems respond slowly to management activities and the possibilities to increase the growth in a short-term perspective and meet swift increases in society's demand for biomass are small. An exception among the silvicultural measures is fertilization which can be applied in...... combination with present management systems and, almost instantly, enhances forest productivity. There may, however, be both economic and environmental constraints to large-scale applications of fertilizers in forest. Here we review the literature concerning biomass production of forests under different...

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

    Directory of Open Access Journals (Sweden)

    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. 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 ...

  7. A new genus of dactylogyrid from the gills of Galaxias maculatus (Osmeriformes: Galaxiidae) in Maullín Basin, Patagonia, Chile.

    Science.gov (United States)

    Viozzi, Gustavo P; Marin, Sandra L; Carvajal, Juan; Brugni, Norma; Mancilla, Melinka

    2007-06-01

    During a parasitological survey of Galaxias maculatus (Jenyns, 1842) in the Maullín Basin (Chilean Patagonia), specimens of a new species of Monogenea were collected from the gills. This species is described as the only member of a proposed new genus, Inserotrema n. gen. (Dactylogyridae, Ancyrocephalinae), characterized by similar hooks with 2 subunits, overlapping gonads, coiled cirrus with counterclockwise rings, articulated accessory piece formed by 2 parts, a needlelike sclerite threading the distal part of the MCO, and a sclerotized midventral vagina. This new genus is proposed for dactylogyrids from gills of galaxiids (Galaxiidae). Inserotrema puyei n. sp. infects gills of G. maculatus from Llanquihue Lake, Maullín River, and Maullín Estuary. This is the first species of Ancyrocephalinae described from gills of a galaxiid. PMID:17626345

  8. EDENES EN EL DESIERTO. SEÑALES DE CAMINOS Y LUGARES EN LA HISTORIA DE LA COLONIZACIÓN DE PATAGONIA ARGENTINA

    Directory of Open Access Journals (Sweden)

    Laura Lucía Miotti

    2015-12-01

    Full Text Available We present a series of reflections on the exploration of and the time for learning about new environments during the initial colonization of America. We consider theoretical elements from archaeology and other fields of study, in order to frame the processes that human groups face when migrating and adapting to uninhabited territory. These landscapes with no history were transformed into social landscapes through practices developed over time. From the perspective of environmental learning, we have analyzed archaeological sites in the Argentine Patagonia indicating human occupations from the Pleistocene-Holocene transition and the Early Holocene era, in order to provide data regarding the modes and times of environmental learning, as well as the materiality and distribution of the first settlements in unknown terrain.

  9. El cambio climático global en la Patagonia desde el viaje de Charles Darwin hasta nuestros días

    Directory of Open Access Journals (Sweden)

    Jorge Rabassa

    2010-08-01

    Full Text Available El viaje del Beagle que trajo a Charles Darwin a América del Sur entre 1832 y 1835 AD y en particular, al territorio argentino, se desarrolló bajo condiciones climáticas muy desfavorables: frías, secas y ventosas, correspondientes a las condiciones predominantes en la última fase de la pequeña edad del hielo, un episodio frío global que caracterizó a los siglos XVII, XVIII y XIX. Esta fase es conocida como mínimo de Dalton, en referencia a la disminución relativa de la frecuencia de las manchas solares, lo cual redunda en una disminución de la radiación solar y como consecuencia, en menores temperaturas medias globales en ese período. Darwin fue perfectamente consciente de dichas condiciones climáticas, que se manifestaban fuertemente en Europa, en particular en los Alpes, y así lo transmite en sus escritos. Desde el viaje de Darwin a la Patagonia, las condiciones climáticas y ambientales cambiaron sustancialmente, especialmente luego de 1850 AD y, finalmente, después de mediados de la década de 1970 AD. Algunas de las más importantes consecuencias del cambio climático global son el aumento de la temperatura media anual o la temperatura estacional, la elevación o disminución de las precipitaciones al nivel regional, el continuo ascenso global del nivel del mar y un incremento significativo de la frecuencia de eventos meteorológicos extremos. El impacto de esos cambios ha sido observado en los glaciares de Patagonia y Tierra del Fuego, por lo menos desde 1978 AD, y particularmente en la última década del siglo XX. Los impactos más notables son la rápida recesión de las márgenes del hielo en los glaciares, el adelgazamiento de la cobertura glacial, la elevación de la línea de nieve regional y la reducción de las áreas andinas bajo condiciones de suelos permanentemente congelados (permafrost, como han demostrado estudios científicos recientes. A la tasa presente de recesión del hielo glacial, la mayoría, si no

  10. 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.

  11. 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...

  12. Reconstruction of a glacial lake outburst flood (GLOF) in the Engaño Valley, Chilean Patagonia: Lessons for GLOF risk management.

    Science.gov (United States)

    Anacona, Pablo Iribarren; Mackintosh, Andrew; Norton, Kevin

    2015-09-15

    Floods from moraine-dammed lake failures can have long standing effects not only on riverine landscapes but also on mountain communities due to the high intensity (i.e. great depth and high velocities) and damaging capacity of glacial lake outburst floods (GLOFs). GLOFs may increase in frequency as glaciers retreat and new lakes develop and there is an urgent need to better understand GLOF dynamics and the measures required to reduce their negative outcomes. In Patagonia at least 16 moraine-dammed lakes have failed in historic time, however, data about GLOF dynamics and impacts in this region are limited. We reconstruct a GLOF that affected a small village in Chilean Patagonia in March 1977, by semi structured interviews, interpretation of satellite images and 2D hydraulic modelling. This provides insight into the GLOF dynamics and the planning issues that led to socioeconomic consequences, which included village relocation. Modelling shows that the water released by the GLOF was in the order of 12-13 × 10(6)m(3) and the flood lasted for about 10h, reaching a maximum depth of ~1.5m in Bahía Murta Viejo, ~ 26 km from the failed lake. The lake had characteristics in common with failed lakes worldwide (e.g. the lake was in contact with a retreating glacier and was dammed by a narrow-steep moraine). The absence of land-use planning and the unawareness of the GLOF hazard contributed to the village flooding. The Río Engaño GLOF illustrates how small-scale and short-distance migration is a reasonable coping strategy in response to a natural hazard that may increase in frequency as atmospheric temperature rises and glaciers retreat. PMID:25958354

  13. Petrogenesis of the Eocene and Mio Pliocene alkaline basaltic magmatism in Meseta Chile Chico, southern Patagonia, Chile: Evidence for the participation of two slab windows

    Science.gov (United States)

    Espinoza, Felipe; Morata, Diego; Pelleter, Ewan; Maury, René C.; Suárez, Manuel; Lagabrielle, Yves; Polvé, Mireille; Bellon, Hervé; Cotten, Joseph; De la Cruz, Rita; Guivel, Christelle

    2005-06-01

    The Meseta Chile Chico (MCC, 46.4°S) is the westernmost exposure of Eocene (lower basaltic sequence, LBS; 55-40 Ma, K-Ar ages) and Mio-Pliocene (upper basaltic sequence, UBS; 16-4 Ma, K-Ar ages) flood basalt volcanism in Patagonia. The MCC is located south of the Lago General Carrera-Buenos Aires (LGCBA), southeast from the present day Chile Triple Junction (CTJ), east of the actual volcanic gap between Southern South Volcanic Zone and Austral Volcanic Zone (SSVZ and AVZ, respectively) and just above the inferred location of the South Chile Ridge segment subducted at ˜6 Ma (SCR-1). Erupted products consist of mainly ne-normative olivine basalt with minor hy-normative tholeiites basalt, trachybasalt and basanite. MCC lavas are alkaline (42.7-53.1 wt.% SiO 2, 3-8 wt.% Na 2O+K 2O) and relatively primitive (Ni: 133-360 ppm, Cr: 161-193 ppm, Co: 35-72 ppm, 4-16.5 MgO wt.%). They have a marked OIB-like signature, as shown by their isotopic compositions ( 87Sr/ 86Sr o=0.70311-0.70414 and ɛNd=+4.7-+5.1) and their incompatible trace elements ratios (Ba/La=10-20, La/Nb=0.46-1.09, Ce/Pb=15.52-27.5, Sr/La1, Sr/La>25, low Ce/Pb, Nb/U) compatible with contamination by arc/slab-derived and/or crustal components. We propose that the genesis and extrusion of magmas is related to the opening of two slab windows due to the subduction of two active ridge segments beneath Patagonia during Eocene and Mio-Pliocene.

  14. Rock-magnetic signature of precipitation and extreme runoff events in south-eastern Patagonia since 51,200 cal BP from the sediments of Laguna Potrok Aike

    Science.gov (United States)

    Lisé-Pronovost, A.; St-Onge, G.; Gogorza, C.; Jouve, G.; Francus, P.; Zolitschka, B.

    2014-08-01

    A 106-m long sediment sequence from the maar lake Laguna Potrok Aike in southern Patagonia was recovered in the framework of the International Continental Scientific Drilling Program (ICDP) Potrok Aike maar lake Sediment Archive Drilling prOject (PASADO). About half of the sedimentary sequence is composed of mass movement deposits (MMDs) and the event-corrected record reaches back to 51,200 cal BP. Here we present a high-resolution rock-magnetic study revealing two sedimentary facies associated with MMDs and characterized by two different types of spurious gyroremanent magnetization (GRM) acquired during static alternating field demagnetization. The first rock-magnetic signature is detected in MMDs composed of reworked sand and tephra material. The signature consists of GRM acquired during demagnetization of the natural remanent magnetization (NRM) and other rock-magnetic properties typical of iron sulfides such as greigite. We interpret these intervals as authigenic formation of iron sulfides in suboxic conditions within the MMD. The second rock-magnetic signature consists of a series of 10 short intervals located on the top of MMDs characterized by GRM acquisition during demagnetization of the isothermal remanent magnetization (IRM). Based on geological, limnological, stratigraphic and climatic evidence these layers are interpreted as reflecting pedogenic hematite and/or goethite brought to the lake by runoff events related to precipitation and permafrost melt. The pedogenic iron minerals mobilized from the catchment most likely settled out of suspension on top of MMDs after a rapid remobilization event. The series of runoff events corresponds to periods of increased lacustrine productivity in Laguna Potrok Aike and are coeval within the limit of the chronology to warm periods of the Last Glacial as recorded in Antarctica, the deglaciation in the mid-latitudes of the Southern Hemisphere and enhanced precipitation during the Early Holocene in southeastern

  15. 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

    Directory of Open Access Journals (Sweden)

    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

  16. 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.

  17. Simulation of Dry Matter Productivity and Water Dynamics in a Chilean Patagonian Range Simulación de la Productividad de Materia Seca y Dinámica del Agua en Praderas de la Patagonia Chilena

    OpenAIRE

    Giorgio Castellaro G; Luis Morales S; Mario Ahumada; Azelio Barozzi

    2010-01-01

    This paper describes a simulation model combining the main components of water balance and growth of perennial grassland steppe in Chilean Patagonia, to estimate long-term annual production (Yr, kg ha-1) and sheep carrying capacity (GC, sheep equivalent [EO] ha-1). The model is based on climate-water balance relationships, where the basic process is evapotranspiration. The model calculates Yr depending on the accumulation of transpiration and the water use efficiency from the time of growth i...

  18. Caracterización y modelación del transporte preferencial de plaguicidas organofosforados en suelos productivos bajo riego. Aplicación al Distrito Colonia Centenario, Patagonia Argentina.

    OpenAIRE

    DUFILHO, ANA CECILIA AMALIA

    2016-01-01

    [EN] In this thesis, transport and fate of organophosphate pesticides - azinphos-methyl and chlorpyrifos- in productive soils from the valley of the Neuquén River in the Patagonia Argentina are analysed. Climate of the region is arid, so traditional fruit production is under flood irrigation. The soils in the floodplain are predominant Aridisols with textures from sandy loam to clay loam. Methodologically, the thesis was based on: field experiments and data and information processing condu...

  19. Una aproximación a la interacción en comunidades de práctica universitarias : El caso de la Universidad Nacional de la Patagonia Austral

    OpenAIRE

    Rivadeneira, Silvia; Oliva, Lidia; De Lucca, Adriana; Ramallo, Eva

    2013-01-01

    Nos proponemos realizar un análisis sobre la interacción social existente en una comunidad de práctica en línea formada por docentes, no docentes y alumnos. El caso abordado es el desempeño de los actores sociales que participan del servicio proporcionado por el Programa de Educación a Distancia de la Universidad Nacional de la Patagonia Austral en su área de influencia.

  20. Flight tracks, Northern California TRACON

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset contains the records of all the flights in the Northern California TRACON. The data was provided by the aircraft noise abatement office...

  1. Northern Fur Seal Food Habits

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains food habits samples, usually scats, collected opportunistically on northern fur seal rookeries and haulouts in Alaska from 1987 to present....

  2. Rocas como símbolos: la selección de materias primas para puntas de proyectil en ambientes mesetarios de Patagonia Rocks As Symbols: The Selection Of Raw Material For Projectile Points In Patagonian Plateau Environments

    Directory of Open Access Journals (Sweden)

    Darío Hermo

    2008-12-01

    Full Text Available Los análisis sobre la tecnología lítica de los cazadores-recolectores que ocuparon la Patagonia argentina se han desarrollado desde perspectivas ecológico-económicas, dejando de lado los aspectos sociales y simbólicos que incidieron en la organización tecnológica. A partir del análisis de conjuntos de puntas de proyectil de diversa cronología y provenientes de ambientes mesetarios de Patagonia se propone el aspecto de las rocas como criterio no excluyentes para la selección de la materia prima en las que fueron manufacturadas. Esta propuesta podría abrir caminos interpretativos hasta ahora en desuso en la región.Analyses of hunter-gatherer lithic technologies from Argentinean Patagonia have been developed from ecological-economic perspectives, leaving aside the social and symbolic aspects that impacted technological organization. Considering the analysis of projectile points of diverse ages from the Patagonian plateaus, the visual aspect of these rocks, such as their color and brightness, is proposed as a non-exclusionary approach for the selection of the raw materials out of which they were manufactured. The proposed approach could open new interpretive paths for the region.

  3. Tornadoes Strike Northern Wisconsin

    Science.gov (United States)

    2007-01-01

    A series of tornadoes ripped through the Upper Midwest region of the United States in the evening of June 7, 2007. At least five different tornadoes touched down in Wisconsin, according to the Associated Press, one of which tore through the Bear Paw Resort in northern Wisconsin. Despite dropping as much as fifteen centimeters (six inches) of rain in some places and baseball-size hail in others, authorities were reporting no deaths attributable to the storm system, and only a smattering of injuries, but considerable property damage in some areas. When the MODIS instrument on NASA's Terra satellite observed the area on June 9, 2007, the track torn through the woods by one of the tornadoes stands out quite clearly. This photo-like image uses data collected by MODIS in the normal human vision range to give a familiar natural-looking appearance. The landscape is largely a checkerboard of farms, towns, roads, and cities. The pale land is predominantly farmland where crops have not fully grown in yet. Dark blue shows the winding path of rivers and lakes dotting the landscape. The large blue lake on the east (right) side of the image is Lake Michigan. Towns and cities, including the city of Green Bay, are gray. To the north side, farmland gives way to dark green as land use shifts from agriculture to the Menominee Indian Reservation and Nicolet National Forest. The diagonal slash through the dark green forested land shows the tornado track. Bare land was revealed where the tornado tore down trees or stripped vegetation off the branches. The high-resolution image provided above is at MODIS' full spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions.

  4. Methanotrophic activity and diversity in different Sphagnum magellanicum dominated habitats in the southernmost peat bogs of Patagonia

    OpenAIRE

    N. Kip; Fritz, C.; Langelaan, E. S.; Pan, Y.; L. Bodrossy; Pancotto, V.; M. S. M. Jetten; Smolders, A.J.P.; Camp, H. J. M.

    2012-01-01

    Sphagnum peatlands are important ecosystems in the methane cycle. Methanotrophs living inside the dead hyaline cells or on the Sphagnum mosses are able to act as a methane filter and thereby reduce methane emissions. We investigated in situ methane concentrations and the corresponding activity and diversity of methanotrophs in different Sphagnum dominated bog microhabitats. In contrast to the Northern Hemisphere peat ecosystems the temperate South American peat bogs are domi...

  5. 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

    Full Text Available Torres del Paine National Park (12th Region, Chile, the Paine Massif and its surroundings are a major milestone concerning three issues: the perception of nature in the Patagonian-Andean environment, the first steps of conservationism in South America and the first scientific studies in this part of the planet. In addition, ever since scientists and travelers were to “discover” this region, Paine has been a benchmark of both the first proposals for nature tourism linked with conservationism, as well as a major challenge for alpine expeditions.

    Due to these circumstances, the doctoral dissertation of the author devotes one entire chapter to analysing the main contributions of the Paine phenomenon to the geographical knowledge of inland Patagonia and to the perception of Torres del Paine as a natural heritage worth preserving. This is precisely the subject of this paper, which gives an insight into the geographical reconnaissance explorations that took place between 1877 and 1896 in the Patagonian inland, under the initiatives of Chilean and Argentinean governments; the first known touristic travel in the Chilean region of Magallanes; the role of the first “visionaries” of Patagonian-Andean tourism in Chile, gathered around Werner Gromsch and the Touring Club; or the geographical, scientific and informative work carried out by Alberto Maria De Agostini. Finally, the article discusses the first alpine expeditions which targeted the summits of the Paine Massif.

    El Parque Nacional de las Torres del Paine (XII Región, Chile, el Macizo Paine y su entorno, constituye un hito en la imagen de la naturaleza del mundo andino patagónico, en los inicios del primer conservacionismo de América del Sur y en los estudios científicos sobre esa parte del Planeta. En relación con ello, además, el Paine ha sido, desde su “descubrimiento” científico y viajero hace más de un siglo, un referente fundamental de las

  6. Forest Typification to Characterize the Structure and Composition of Old-growth Evergreen Forests on Chiloe Island, North Patagonia (Chile)

    OpenAIRE

    Jan R. Bannister; Pablo J. Donoso

    2013-01-01

    The Evergreen forest type develops along the Valdivian and North-Patagonian phytogeographical regions of the south-central part of Chile (38° S–46° S). These evergreen forests have been scarcely studied south of 43° S, where there is still a large area made up of old-growth forests. Silvicultural proposals for the Evergreen forest type have been based on northern Evergreen forests, so that the characterization of the structure and composition of southern Evergreen forests, e.g., their typific...

  7. 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

  8. Rock-magnetic signatures of aeolian activity, precipitation and extreme runoff events from the sediments of Laguna Potrok Aike (southern Patagonia) since 51,200 cal BP

    Science.gov (United States)

    St-Onge, G.; Lisé-Pronovost, A.; Gogorza, C. S. G.; Haberzettl, T.; Jouve, G.; Francus, P.; Ohlendorf, C.; Gebhardt, C.; Zolitschka, B.

    2014-12-01

    The sedimentary archive from Laguna Potrok Aike is the only continuous record reaching back to the last Glacial period in continental southeastern Patagonia. Here we use high-resolution u-channel, as well as discrete rock-magnetic and physical grain size data from the 106 m long core (~51,200 cal BP) of site 2 of the ICDP Potrok Aike maar lake Sediment Archive Drilling project (PASADO) in order to develop magnetic proxies of dust and wind intensity, as well as precipitation and extreme runoff events. Rock-magnetic analyses indicate the magnetic mineral assemblage is dominated by detrital magnetite and that low field magnetic susceptibility (kLF) can be interpreted as a dust indicator in the dust source of southern Patagonia at the millennial time scale. On shorter time scales however, kLF variability is correlated to ferrimagnetic grain size and coercivity. Comparison to physical grain-size data indicates that the median destructive field of the isothermal remanent magnetisation (MDFIRM) mostly reflects medium to coarse magnetite bearing silts typically transported by winds for short-term suspension and that MDFIRM can be interpreted as a wind-intensity proxy, with stronger winds capable of transporting coarser silts to the lake. In addition, about half of the sedimentary sequence is composed of mass movement deposits (MMDs). Within these MMDs, two distinct sedimentary facies can easily be identified. The first rock-magnetic signature is detected in MMDs composed of reworked sand and tephra material. The signature consists of a gyroremanent magnetisation (GRM) acquired during demagnetisation of the natural remanent magnetisation (NRM) and other rock-magnetic properties typical of iron sulfides such as greigite. We interpret these intervals as authigenic formation of iron sulfides in suboxic conditions within the MMD. The second rock-magnetic signature consists of 10 short intervals located on the top of MMDs characterized by GRM acquisition during demagnetisation

  9. 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.

  10. 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

  11. Charles Darwin and the oldestglacial events in Patagonia: the erratic blocks of the Río Santa Cruz valley Charles Darwin y las glaciacionesmás antiguas de Patagonia: los bloques erráticos del alto valle del Río Santa Cruz

    Directory of Open Access Journals (Sweden)

    Jorge Strelin

    2009-04-01

    Full Text Available Althoughthe depositational environment assigned by Darwin to the large erratic blocksand gravels in the Río Santa Cruz valley has been reinterpreted, hisgeomorphological and stratigraphic observations are still in force. The largeerratic blocks he described as crowning the Condor Cliff terrace and spread atthe bottom of the valley just east of this locality (Sites 2 and 3, are nowinterpreted as indicators of the maximum glacial expansion in Patagonia.Similar blocks, though of a different lithology, accumulated over a lowerterrace located up-valley (Site 4, are now linked to moraines and glacifluvialterraces of the Penultimate Glaciation. Finally, in addition to the erraticblock discovered by Darwin in the lower Río Santa Cruz valley (Site 1, thereare others - recently discovered - which probably account for a catastrophicevent ascribed to a big glacier-lake outburst during the last interglacial.No obstante haber sidoreinterpretado el ambiente depositacional asignado por Darwin a los grandesbloques erráticos y rodados del valle del río Santa Cruz, siguen vigentes susobservaciones geomorfológicas y estratigráficas. Los grandes bloques erráticosque describe coronando la terraza de Condor Cliff y dispersos en el fondo delvalle inmediatamente al este de esta localidad (Sitios 2 y 3, soninterpretados ahora como indicadores de la máxima expansión glaciaria de la Patagonia. Bloques similares, aunque de dispar litología, acumulados sobre una terraza másbaja situada río arriba (Sitio 4, se vinculan actualmente a morenas y terrazasglacifluviales de la Penúltima Glaciación. Finalmente, al bloque erráticodescubierto por Darwin en el tramo inferior del valle del río Santa Cruz (Sitio1, se le suman otros -de reciente descubrimiento- que probablemente den cuentade un evento catastrófico atribuible al vaciamiento de un gran lago glaciardurante el último interglaciar.

  12. NORTHERN PUGET SOUND MARINE MAMMALS

    Science.gov (United States)

    A baseline study of the marine mammals of northern Puget Sound and the Strait of Juan de Fuca was undertaken from November 1977 to September 1979 emphasizing certain aspects of the biology of the harbor seal, which is the most abundant marine mammal in this area. The local abunda...

  13. Lyme Disease in Northern California

    OpenAIRE

    Campagna, Joan; Lavoie, Paul E.; Birnbaum, Neal S.; Furman, Deane P.

    1983-01-01

    Lyme disease is a recently described clinical entity with cutaneous, neurologic, articular and cardiac manifestations. Since the original description of the disease in 1977, more than 500 cases have been reported. Although the vast majority of patients have been from the area near Lyme, Connecticut, we have seen four patients from northern California with various aspects of Lyme disease.

  14. Standardized catch rate of cockfish, Callorhinchus callorynchus, in a bottom trawl fishery of Patagonia: Is it possible its use as a predictor of abundance trend?

    Directory of Open Access Journals (Sweden)

    Juan F. Bernasconi

    2015-06-01

    Full Text Available Abstract The catch per unit of effort (CPUE data of cockfish, Callorhinchus callorynchus, during 1986-2011 was evaluated for the bottom trawl fishery of the San Matías gulf (Patagonia, Argentina. The objective of this work was to detect what are the factors related to fishery dynamic that affect catch rate of cockfish and to assess standardized CPUE by General linear models (GLMs and General linear mixed models (GLMMs as a relative abundance index. The annual trend of the catch rate indicated an increase during the evaluated period. The nominal CPUE and the indices standardized by the Delta-GLM and Delta-GLMM showed the same annual trend, with increases of 57%, 61.1% and 60.7%, respectively. The LogNormal models have the best-fit model and explained 23.5% of the total variability. The factors year, month, depth and hake CPUE explained the highest variability. The analysis of the models indicated that the catch rate of cockfish is subject to the lack of an homogeneous distribution of the fishing effort during different years, months and vessels. This was related to the fleet dynamic searching the targets species. The increasing trend of CPUE and landings would be indicating an increase in effort directionality to the cockfish in the last decade.

  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. 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. PMID:25692466

  17. 40Ar/ 39Ar dating of the Jurassic volcanic province of Patagonia: migrating magmatism related to Gondwana break-up and subduction

    Science.gov (United States)

    Féraud, G.; Alric, V.; Fornari, M.; Bertrand, H.; Haller, M.

    1999-10-01

    The Mesozoic large igneous province (LIP) of Patagonia (southern South America), which is one of the largest silicic provinces on Earth has been investigated by the 40Ar/ 39Ar method. Twenty-seven ages considered as valid, including twenty plateau ages, show that the volcanic activity, ranging from 187 to 144 Ma, occurred between and contemporaneously with the initial break-up of Gondwana (starting with the Karoo-Antarctic-Tasmanian (KAT) flood basalt province) in the east, and a subduction in the west. The data display a regular decreasing of ages from the ENE (187 Ma) to the WSW (144 Ma) along about 650 km, apparently related to the tectonic structure in half-grabens oriented NNW-SSE. The good fitting of this trend with the opening of the Rocas Verdes-Sarmiento marginal basin favors a space time evolution of this continental volcanism culminating towards the SSW in a continental disruption behind the magmatic arc. The observed age progression of volcanism may be the result of the variations of the physical characteristics of the subduction. The spreading and thermal effect of the KAT plume may have an additional effect and also could account for the unusually large volume of magma.

  18. U-Pb zircon constraints on the age of the Cretaceous Mata Amarilla Formation, Southern Patagonia, Argentina: Its relationship with the evolution of the Austral Basin

    International Nuclear Information System (INIS)

    Despite the abundant fossil content of the Mata Amarilla Formation (Southern Patagonia, Santa Cruz Province, Argentina), its age has always generated a considerable number of questions and debates. The chronological data provided by invertebrates, dinosaurs, fish, turtles, plesiosaurs and fossil flora are contradictory. In this work, twenty U-Pb spot analyses by laser ablation were carried out on the outer parts of the zoned zircon crystals from a tuff layer of the middle section of the Mata Amarilla Formation, yielding a U-Pb concordia age of 96.23±0.71 Ma, which corresponds to the middle Cenomanian. The deposition of the lower section of the Mata Amarilla Formation marks the onset of the foreland stage of the Austral Basin (also known as Magallanes Basin); this transition is characterized by the west-east shift of the depositional systems, which is consistent with the progradation of the Cretaceous fold-and-thrust belt. Thus, the onset of the foreland stage could have occurred between the upper Albian and lower Cenomanian, as the underlying Piedra Clavada Formation is lower Albian in age. On comparing the data obtained with information from the Ultima Esperanza Province in Chile, it can be suggested that the initiation of the closure of the Rocas Verdes Marginal Basin occurred simultaneously

  19. Baseline element composition of foliose and fruticose lichens along the steep climatic gradient of SW Patagonia (Aisén Region, Chile).

    Science.gov (United States)

    Monaci, Fabrizio; Fantozzi, Federica; Figueroa, Ricardo; Parra, Oscar; Bargagli, Roberto

    2012-09-01

    Samples of foliose (Nephroma antarcticum) and fruticose (Usnea sp.) lichens were collected across a steep climatic and vegetation gradient in a remote, almost pristine region of SW Chilean Patagonia. Concentrations of major and trace elements in lichens from the rainforest were among the lowest ever reported worldwide for foliose and fruticose lichens and can be considered background levels for the region. The two lichen growth forms showed different elemental compositions mainly due to the greater capacity of foliose thalli to intercept elements from windborne and canopy-leached particles. The patterns of spatial variation in the chemical composition of lichens were effectively explained by statistical methods and reflected the different availability of wet and dry deposition along the steep climatic gradient. Baseline values established for N. antarcticum samples growing in temperate Nothofagus forests were therefore distinct from those of samples growing in more open, drier habitats. The fruticose Usnea sp. showed a higher affinity for atmophile Hg, low concentrations of lithophilic elements, and the same baseline composition whether from temperate forests or from dry, barren environments. The provided background and baseline values against which variations can be measured will be useful in the early detection of local or regional climatic and environmental change, especially in view of the planned construction of hydropower dams under the recently approved HidroAysén Project. PMID:22790117

  20. Aproximaciones al análisis de los conflictos ambientales en la Patagonia: reflexiones de historia reciente 1980-2005 Evaluation of environmental conflicts analyses in Patagônia: reflections on the recent history (1980-2005

    Directory of Open Access Journals (Sweden)

    Daniel Norberto Blanco

    2006-12-01

    Full Text Available Este texto trata de una historia social del ambiente en la región de Patagonia, en especial las discusiones sobre el presente y el futuro de la región. En el trabajo confluyen tres líneas de reflexión. La primera consiste en el análisis de los conflictos ambientales de la historia reciente de la Patagonia. La segunda línea de reflexión resulta de una mirada a la protesta social ante emprendimientos que pusieron en riesgo el ambiente. La tercera línea de reflexión hace una discusión acerca del cambio de representaciones sobre la Patagonia, sobre el ambiente y el territorio. Considerando que se trata de un territorio sometido al despojo y a la extracción desde su conquista militar se tratará de explicar por qué en las últimas décadas se verifica un ejercicio activo de la ciudadanía en defensa del ambiente.The article deals with a social history of environment in the region of Patagônia and is especially focused on the present and the future of the region. Three different lines of reflections are examined. The first is the analysis of the environmental conflicts in the recent history of Patagônia. The second is a look at the protest movements against businesses in the region that risk the environment A third line of reflection discusses the changes in the representations of Patagônia, environment and territory. The article also gives an explanation of why an active citizenship movement in defense of the environment has taken place in the past decades, considering that Patagônia is a territory that has been exploited since its military conquest.

  1. Consideraciones sobre las percas (Percichthys colhuapiensis y P.trucha) de la Patagonia norte - Años 1955 a 1957. Comparaciones con material de años recientes.

    OpenAIRE

    Amalfi, Marína

    2009-01-01

    Este trabajo se basa en los muestreos sobre las percas (Percichthys sp) realizado entre los años 1955 a 1957 por María Luisa Fuster de Plaza y Enrique E. Boschi, ambos investigadores se desempañaban en el Departamento de Investigaciones Pesqueras de la Dirección Nacional de Pesca, dependiente del Ministerio de Agricultura y Ganadería de la Nación de entonces. Las tareas se llevaron a cabo principalmente en varios cuerpos de agua léntica y lóticas de la región de la Patagonia Norte (Provinc...

  2. 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.

  3. Offshore northern Europe, the challenges

    International Nuclear Information System (INIS)

    This paper relates to challenges of the offshore activity in the North Sea. It is appropriate to address these challenges in the context of generating values through efficient management of resources, markets, safety and technology, as the challenges lie therein. The petroleum industry is built to turn natural resources into market value, assuring broad benefits to stake holders and shareholders. In the following, the challenges facing the industry the industry offshore Northern Europe is examined on this background

  4. Carboniferous geology of Northern England

    OpenAIRE

    Waters, Colin N.

    2009-01-01

    The British Geological Survey (BGS) has produced a wholesale rationalisation of Carboniferous lithostratigraphical nomenclature. This presentation describes the Carboniferous stratigraphy of northern England, illustrated with research carried out as part of recent BGS mapping projects. During the Tournaisian and Visean a phase of north–south rifting resulted in the development of grabens and half-grabens, separated by platforms and tilt-block highs. Visean marine transgressions re...

  5. Viral diseases of northern ungulates

    OpenAIRE

    Frölich, K.

    2000-01-01

    This paper describes viral diseases reported in northern ungulates and those that are a potential threat to these species. The following diseases are discussed: bovine viral diarrhoea/mucosal disease (BVD/MD), alphaherpesvirus infections, malignant catarrhal fever (MCF), poxvirus infections, parainfluenza type 3 virus infection, Alvsborg disease, foot-and-mouth disease, epizootic haemorrhage disease of deer and bluetongue disease, rabies, respiratory syncytial virus infection, adenovirus infe...

  6. Methanotrophic activity and diversity in different Sphagnum magellanicum dominated habitats in the southernmost peat bogs of Patagonia

    Directory of Open Access Journals (Sweden)

    M. S. M. Jetten

    2011-09-01

    Full Text Available Sphagnum peatlands are important ecosystems in the methane cycle. Methanotrophs living in and on the Sphagnum mosses are able to act as a methane filter and thereby reduce methane emissions. We investigated in situ methane concentrations and the corresponding activity and diversity of methanotrophs in different Sphagnum dominated bog microhabitats. In contrast to the Northern Hemisphere peat ecosystems the temperate South American peat bogs are dominated by one moss species; Sphagnum magellanicum. This permitted a species-independent comparison of the different bog microhabitats. Potential methane oxidizing activity was found in all Sphagnum mosses sampled and a positive correlation was found between activity and in situ methane concentrations. Substantial methane oxidation activity (23 μmol CH4 gDW−1 day−1 was found in pool mosses and could be correlated with higher in situ methane concentrations (>35 μmol CH4 l−1 pore water. Little methanotrophic activity (4 gDW−1 day−1 was observed in living Sphagnum mosses from lawns and hummocks. Methane oxidation activity was relatively high (>4 μmol CH4 gDW−1 day−1 in Sphagnum litter situated at depths around the water levels and rich in methane. The total bacterial community was studied using 16S rRNA gene sequencing and the methanotrophic communities were studied using a pmoA microarray and a complementary pmoA clone library. The methanotrophic diversity was similar in the different habitats of this study and surprisingly comparable to the methanotrophic diversity found in peat mosses from the Northern Hemisphere. The pmoA microarray data indicated that both alpha- and gammaproteobacterial methanotrophs were present in all Sphagnum mosses, even in those mosses with a low initial methane oxidation activity. Prolonged incubation of Sphagnum mosses from lawn and hummock with methane revealed that the methanotrophic community present was viable and showed an increased activity within 15

  7. 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

    Directory of Open Access Journals (Sweden)

    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

  8. 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

  9. Pteridophyta collected in Northern Nigeria and Northern Cameroon

    Directory of Open Access Journals (Sweden)

    Jan kornaś

    2014-02-01

    Full Text Available 25 species of Pteridophyta were collected in Northern Nigeria (mainly the Lake Chad Basin and the Mandara Mts. and in the neighbouring parts of Cameroon. 11 of them have not been recorded previously from this area: Isoetes schweinfurthii A. Br. in Bak., Selaginella tenerrima A. Br. ex Kuhn, Ophioglossum gomenzianum Welw. ex A. Br., Marsilea coromandeliana Willd., M. distorta A. Br., M. nubica A. Br., M. subterranea Lepr. ex A. Br., Azolla africana Desv., Ceratopteris richardii Brogn., Adiantum capillus-veneris Linn., and Actiniopleris semiflabellata Pic. Ser.

  10. Caracterización de tres cepas bacterianas capaces de fijar nitrógeno y biodegradar hidrocarburos aisladas de un suelo de la Patagonia

    Directory of Open Access Journals (Sweden)

    A.J. Acuña

    2010-01-01

    Full Text Available El objetivo de este trabajo fue caracterizar tres microorganismos capaces de biodegradar hidrocarburos en ausencia de nitrógeno aislados a partir de un suelo de la Patagonia con una larga historia de contaminación por petróleo y sus derivados. Para ello se aislaron tres cepas bacterianas de un suelo patagónico con baja concentración de nitrógeno y contaminado con hidrocarburos. Estos fueron identificados por ARNr 16S y ácidos grasos de membrana. También se estudiaron sus perfiles de biodegradación de hidrocarburos en presencia y en ausencia de nitrógeno con hidrocarburos alifáticos, cíclicos, aromáticos y poliaromáticos. La capacidad de realizar fijación biológica de nitrógeno se estudió por reducción de acetileno y detección del gen nifD. Por otro lado, se realizó un estudio por desarrollo en cultivo líquido para conocer la adaptación a diferentes pH, entre 5 y 9, temperatura, de 15 a 65 °C, y concentraciones crecientes de NaCl entre 0 y 3M. Los microorganismos aislados correspondieron a los géneros Pseudomonas, Bacillus y Gordonia, todos con capacidad de fijar nitrógeno. Las cepas biodegradaron casi la totalidad de los hidrocarburos ensayados en presencia y ausencia de nitrógeno y tuvieron una buena adaptación a los cambios de pH, temperatura y concentración de NaCl, demostrando una buena adaptación a los principales factores de estrés en los suelos patagónicos.

  11. Del Recurso Humano al humano con recursos: una propuesta en el estudio de encadenamientos socioproductivos para el Turismo de intereses especiales en el territorio Patagonia Verde Chile

    Directory of Open Access Journals (Sweden)

    Guillermo Sebastián Pacheco Habert

    2012-01-01

    Full Text Available El tema del humano con recurso, enfoque de este trabajo, tiene un papel importantísimo a la hora de transitar de estrategias competitivas hacia estrategias colaborativas, sobre todo cuando se perciben logros ecosocioeconómicos que avanzan hacia la dirección de un desarrollo territorial. Se tiene como hipótesis, que desde el enfoque de los encadenamientos socioproductivos, centrado en el turismo de intereses especiales, es posible comprender y establecer objetivos comunes dentro de actores, organizaciones, emprendimientos y comunidades locales. El objetivo de este artículo es proponer una aproximación teórica sobre el TIE (Turismo de Intereses Especiales sobre las aglomeraciones, sobre los encadenamientos socioproductivos y sobre el enfoque del humano con recurso, para posteriormente relatar los primeros resultados de esta investigación realizada en los cinco municipios que hacen parte del territorio turístico denominado "Patagonia Verde", en el sur de Chile. A partir de la identificación de actores clave, se aplicaron entrevistas a éstos y fichas de caracterización a emprendimientos. Posteriormente se identificaron fortalezas y oportunidades que puedan ser potenciadas a partir de la perspectiva del humano con recurso. A partir de los encadenamientos socioproductivos, contar con individuos conscientes y proactivos dentro de las instituciones y organizaciones en tareas y ejes estratégicos del desarrollo turístico y que compartan con la perspectiva del desarrollo territorial sustentable, es uno de los desafíos que aquí proponemos. Son los sujetos quienes son capaces de generar las condiciones institucionales para otra forma de comprender y actuar en Turismo.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Asimetría en el postcráneo de poblaciones humanas prehispánicas de Pampa y Patagonia

    Directory of Open Access Journals (Sweden)

    Béguelin, Marien

    2007-01-01

    Full Text Available En este trabajo se evaluó el patrón de asimetría bilateral de muestras esqueletales de poblaciones cazadoras-recolectoras de Pampa y Patagonia (n=161 en el marco de una investigación centrada en la variación geográfica de la morfología postcraneal. Se analizaron tanto la presencia como el grado de asimetría observado en los huesos largos de los miembros superiores e inferiores (húmero, radio, fémur, tibia. Se examinó también el dimorfismo sexual y la variación interpoblacional. Los análisis se basaron en los porcentajes direccional y absoluto de asimetría. El primero de ellos considera tanto la magnitud de la asimetría como la lateralidad en tanto el segundo se concentra en la magnitud. Se encontró un patrón general de asimetría en todas las muestras, siendo más marcado en los miembros superiores que en los inferiores, y hacia el lado derecho. Los miembros inferiores evidencian una asimetría muy leve, y el fémur mostró una tendencia hacia la izquierda en todas sus dimensiones (fenómeno conocido como asimetría cruzada. Las asimetrías de longitud son mucho menos pronunciadas que las de diámetros de diáfisis. En todas las muestras los grupos masculinos presentan un grado mayor de asimetría que los femeninos. Se discutirán alternativas en torno a la influencia de distintos factores, a saber sexo, tipo de medida (longitud o diámetro y diferencias interpoblacionales sobre el tipo y grado de asimetría.

  14. Estudio de las modificaciones postdepositacionales de la superficie ósea en una muestra de entierros humanos de Patagonia centro-meridional

    Directory of Open Access Journals (Sweden)

    Del Papa, Mariano C.

    2001-01-01

    Full Text Available La adecuada interpretación de los patrones observados en la distribución sexual, etárea y cronológica de los indicadores biológicos considerados en los estudios bioarqueológicos depende, en gran medida, del conocimiento de la historia tafonómica y postdepositacional de las muestras utilizadas. Sin embargo, con frecuencia este es un aspecto poco tratado en este tipo de estudios. Como un medio establecer la comparabilidad entre muestras provenientes de distintos sectores de Patagonia Centro-Meridional (Cuencas de los lagos Salitroso y Cardiel y Pampa de la Chispa, se realizó un análisis cuali-cuantitativo de la distribución intra e intermuestral de los efectos producidos sobre la superficie de los huesos por distintos agentes postdepositacionales (v.g. meteorización, depositación de CaCO3 y MnO2, marcas de raíces y de roedores, combustión, pérdida de materia ósea, etc.. Los resultados obtenidos hasta el presente muestran que es esperable no sólo una variación significativa en el impacto de estos agentes entre entierros de distinto tipo (i.e. entierros en chenques y en hoquedades naturales sobre rocas, sino también en el interior de cada estructura, dependiendo de la profundidad de depositación, grado potencial de exposición, sexo y edad.

  15. 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)

  16. Solapamiento trófico entre el lobo marino de un pelo Otaria flavescens y la pesquería de arrastre demersal del golfo San Matías, Patagonia, Argentina Trophic overlap between the South American sea lion Otaria flavescens and the demersal trawl fishery in San Matías Gulf, Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    María Alejandra Romero

    2011-07-01

    Full Text Available A nivel internacional, paralelo a la declinación y al colapso de pesquerías de gran escala, surgió un interés creciente por el estudio de las interacciones entre mamíferos marinos y pesquerías. El golfo San Matías (Patagonia, Argentina es considerado un ecosistema pesquero independiente de las aguas de la Plataforma Continental Argentina, con condiciones oceanográficas y biológicas particulares. La condición de sistema semi-cerrado podría generar escenarios particulares para la interacción entre la flota pesquera de arrastre de fondo y la población de lobos marinos de un pelo Otaria flavescens. En el presente trabajo se caracterizó la dieta del predador y la composición de las capturas pesqueras a fin de evaluar el solapamiento trófico entre ambos componentes. A partir de este análisis y la comparación de las tallas de las presas consumidas, se encontró que la posibilidad de una interacción competitiva entre la flota pesquera y los lobos marinos, a partir de la utilización de recursos similares, sería baja en el ecosistema del golfo San Matías.As world fisheries began to decline and massive collapses were observed, the competition between marine mammals and fisheries became an issue of growing concern. San Matías Gulf (Patagonia, Argentina is considered to be a fishery ecosystem independent of the Argentine Continental Shelf waters, with particular oceanographic and biological properties. As a semi-enclosed ecosystem, this gulf may generate particular scenarios for interactions between the demersal trawl fishery fleet and the population of South American sea lions Otaria flavescens. In this paper, the diet of the top predator and the composition of fishery catches were characterized in order to assess the trophic overlap between these two components. This analysis and a comparison of the sizes of prey consumed revealed a low probability of competition for similar resources between the fishing fleet and the marine mammals

  17. 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

    Directory of Open Access Journals (Sweden)

    VALERIA OJEDA

    2003-09-01

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

  18. 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

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

    Directory of Open Access Journals (Sweden)

    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

  20. Northern communities sustainable energy initiative

    Energy Technology Data Exchange (ETDEWEB)

    Oltman, Ursula; Widmeyer, Scott; Moen, Harlan

    2010-09-15

    The Circumpolar North may provide the solution to the world's most urgent problems. Combining new technologies with the resources, opportunities and needs of the north, the Arctic region may become instrumental in promoting nature's ability to sequester natural carbons while supplying future energy demands to the world. With the technologies for efficiencies and CCS, the abundant supply of natural gas exists for an efficient northern network of electrical generating facilities in the circumpolar region. A symbiotic relationship between facilities can ensure dependable clean electricity and support East-West distribution of power across international time zones strategically connected to southern grids.

  1. Northern Manitoba, northern Saskatchewan, and the Saskatchewan River Delta: Waterfowl breeding population survey: 1997

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the Waterfowl Breeding Population and Habitat Survey for northern Manitoba, northern Saskatchewan, and the Saskatchewan River Delta during...

  2. Waterfowl production survey: Northern Saskatchewan, northern Manitoba, Saskatchewan River Delta: July 10-22, 1973

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the Waterfowl Production and Habitat Survey for northern Saskatchewan, northern Manitoba, and the Saskatchewan River Delta during 1973. The...

  3. Northern Alaska Landscape/Permafrost GIS Data

    Data.gov (United States)

    Arctic Landscape Conservation Cooperative — This data set represents an updated Ecological Subsection Map for Northern Alaska. This update includes permafrost mapping to include the following new layers:...

  4. Giant Reed Distribution - Northern California [ds333

    Data.gov (United States)

    California Department of Resources — The Arundo Distribution layer is a compilation of Arundo donax observations in northern and central California, obtained from several sources, including Arundo...

  5. Northern pipelines : challenges and needs

    Energy Technology Data Exchange (ETDEWEB)

    Dean, D.; Brownie, D. [ProLog Canada Inc., Calgary, AB (Canada); Fafara, R. [TransCanada PipeLines Ltd., Calgary, AB (Canada)

    2007-07-01

    Working Group 10 presented experiences acquired from the operation of pipeline systems in a northern environment. There are currently 3 pipelines operating north of 60, notably the Shiha gas pipeline near Fort Liard, the Ikhil gas pipeline in Inuvik and the Norman Wells oil pipeline. Each has its unique commissioning, operating and maintenance challenges, as well as specific training and logistical support requirements for the use of in-line inspection tools and other forms of integrity assessment. The effectiveness of cathodic protection systems in a permafrost northern environment was also discussed. It was noted that the delay of the Mackenzie Gas Pipeline Project by two to three years due to joint regulatory review may lead to resource constraints for the project as well as competition for already scarce human resources. The issue of a potential timing conflict with the Alaskan Pipeline Project was also addressed as well as land use issues for routing of supply roads. Integrity monitoring and assessment issues were outlined with reference to pipe soil interaction monitoring in discontinuous permafrost; south facing denuded slope stability; base lining projects; and reclamation issues. It was noted that automatic welding and inspection will increase productivity, while reducing the need for manual labour. In response to anticipated training needs, companies are planning to involve and train Aboriginal labour and will provide camp living conditions that will attract labour. tabs., figs.

  6. Groundwater management in northern Iraq

    Science.gov (United States)

    Stevanovic, Zoran; Iurkiewicz, Adrian

    2009-03-01

    Groundwater is vital and the sole resource in most of the studied region of northern Iraq. It has a significant role in agriculture, water supply and health, and the elimination of poverty in rural areas. Although Iraq is currently dramatically disturbed by complex political and socio-economic problems, in its northern part, i.e. the Kurdish-inhabited region, fast urbanization and economic expansion are visible everywhere. Monitoring and water management schemes are necessary to prevent aquifer over-exploitation in the region. Artificial recharge with temporary runoff water, construction of subsurface dams and several other aquifer management and regulation measures have been designed, and some implemented, in order to improve the water situation. Recommendations, presented to the local professionals and decision-makers in water management, include creation of Water Master Plans and Water User Associations, synchronization of drilling programmes, rehabilitation of the existing well fields, opening of new well fields, and the incorporation of new spring intakes in some areas with large groundwater reserves, as well as construction of numerous small-scale schemes for initial in situ water treatment where saline groundwater is present.

  7. Illuminating Northern California's Active Faults

    Science.gov (United States)

    Prentice, Carol S.; Crosby, Christopher J.; Whitehill, Caroline S.; Arrowsmith, J. Ramón; Furlong, Kevin P.; Phillips, David A.

    2009-02-01

    Newly acquired light detection and ranging (lidar) topographic data provide a powerful community resource for the study of landforms associated with the plate boundary faults of northern California (Figure 1). In the spring of 2007, GeoEarthScope, a component of the EarthScope Facility construction project funded by the U.S. National Science Foundation, acquired approximately 2000 square kilometers of airborne lidar topographic data along major active fault zones of northern California. These data are now freely available in point cloud (x, y, z coordinate data for every laser return), digital elevation model (DEM), and KMZ (zipped Keyhole Markup Language, for use in Google Earth™ and other similar software) formats through the GEON OpenTopography Portal (http://www.OpenTopography.org/data). Importantly, vegetation can be digitally removed from lidar data, producing high-resolution images (0.5- or 1.0-meter DEMs) of the ground surface beneath forested regions that reveal landforms typically obscured by vegetation canopy (Figure 2).

  8. Environmental overview of geothermal development: northern Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Slemmons, D.B.; Stroh, J.M.; Whitney, R.A. (eds.)

    1980-08-01

    Regional environmental problems and issues associated with geothermal development in northern Nevada are studied to facilitate environmental assessment of potential geothermal resources. The various issues discussed are: environmental geology, seismicity of northern Nevada, hydrology and water quality, air quality, Nevada ecosystems, noise effects, socio-economic impacts, and cultural resources and archeological values. (MHR)

  9. Northern Parkway PTA Makes Health a Habit

    Science.gov (United States)

    Ferdinand, Marilyn

    2011-01-01

    Health and fitness have been on the agenda of Northern Parkway Elementary School for quite some time, thanks to the concerted efforts of its involved and active PTA officers and members. For the past five years, the Northern Parkway PTA has held a popular and well-attended Family Fun and Fitness Night and has complemented the activities and…

  10. Interannual variability in temporal patterns of Chlorophyll-a and their potential influence on the supply of mussel larvae to inner waters in northern Patagonia (41-44°S)

    Science.gov (United States)

    Lara, Carlos; Saldías, Gonzalo S.; Tapia, Fabian J.; Iriarte, José Luis; Broitman, Bernardo R.

    2016-03-01

    Environmental forcing of biophysical processes can have deep influences on patterns of supply of planktonic larvae to benthic communities in coastal marine ecosystems. We investigated the role of environmental forcing following a recent interannual decrease in larval supply in the Inner Sea of Chiloé (41-45°S) using direct observations and environmental time series over the period 2003-2014. To examine the temporal structure of larval supply and potential associations with environmental forcing (approximated using satellite chlorophyll-a and sea surface temperature), we used wavelet analysis and lagged correlations to test the hypothesis of an association between larval availability and changes in the seasonal cycle of chlorophyll-a concentration, sea surface temperature, and relevant climate variability (Pacific Decadal Oscillation, El Niño-Southern Oscillation and Southern Annular Mode). Our results indicate that a weakening in the annual cycle of chlorophyll-a concentration and abnormally cold sea surface temperature during 2009-2010 can be related to the observed disruption in larval supply to the Inner Sea of Chiloé starting during the 2010-2011 season. The potential influence of climate variability is further discussed as the spatial extent and temporal persistence observed suggest that other ecological processes might have also been affected, and consequently, we suggest a link to transient large-scale climatic forcing.

  11. Earliest Urbanism in Northern Mesopotamia

    DEFF Research Database (Denmark)

    Skuldbøl, Tim Boaz Bruun

    This dissertation is based on new evidence from the most recent archaeological fieldwork conducted at Tell Brak in northeastern Syria, one of the most important early cities in Mesopotamia. An analysis of this data underscores the transformative and creative nature of the urbanization process...... and hypotheses about the development of early cities in Mesopotamia, and has important implications for understanding the development of early cities in general, as well as their functional composition. This study primarily draws upon the most recent published reports, and from unpublished data collected from...... fieldwork on the mound of Tell Brak and in its immediate surroundings, as well as the author’s own new comparative ceramic studies, which provide the basis for improvements in chronology of the Late Chalcolithic period in northern Mesopotamia. This extensive empirical material is presented as archaeological...

  12. TSUNAMI HAZARD IN NORTHERN VENEZUELA

    Directory of Open Access Journals (Sweden)

    B. Theilen-Willige

    2006-01-01

    Full Text Available Based on LANDSAT ETM and Digital Elevation Model (DEM data derived by the Shuttle Radar Topography Mission (SRTM, 2000 of the coastal areas of Northern Venezuela were investigated in order to detect traces of earlier tsunami events. Digital image processing methods used to enhance LANDSAT ETM imageries and to produce morphometric maps (such as hillshade, slope, minimum and maximum curvature maps based on the SRTM DEM data contribute to the detection of morphologic traces that might be related to catastrophic tsunami events. These maps combined with various geodata such as seismotectonic data in a GIS environment allow the delineation of coastal regions with potential tsunami risk. The LANDSAT ETM imageries merged with digitally processed and enhanced SRTM data clearly indicate areas that might be prone by flooding in case of catastrophic tsunami events.

  13. Contamination from Russian Northern Fleet

    International Nuclear Information System (INIS)

    This report, from an environmental group known as Bellona and based in Norway, is highly critical of the Russian navy's apparently short-sighted attitude to nuclear power's longer term economic and environmental consequences. Six main sources of radioactive contamination from the activities of the Russian Northern Fleet are summarised, namely, the still increasing numbers of nuclear-powered submarines in service, naval bases, shipyards (including the storage of solid and liquid radioactive wastes and spent nuclear fuels), safety problems with service ships providing transport for nuclear materials, the whole unaddressed problem of decommissioning nuclear submarines due to go out of service (eighty-eight vessels at present), and accidents involving nuclear submarines. (UK)

  14. Intergroup trust in Northern Ireland.

    Science.gov (United States)

    Tam, Tania; Hewstone, Miles; Kenworthy, Jared; Cairns, Ed

    2009-01-01

    Although prominent political agendas have placed a great deal of importance on building trust in postconflict areas, there has been a lack of empirical research on its role in areas of intergroup conflict. The authors conducted two studies to examine the relationship between trust and intergroup behavioral tendencies-and the potential for intergroup contact to build trust in Northern Ireland. Study 1 showed that outgroup trust mediates the impact of intergroup contact on behavioral tendencies toward the outgroup. Study 2 revealed the importance of trusting the outgroup over simply liking the outgroup; establishing outgroup trust is crucial, as trust is a stronger predictor of behavioral tendencies toward the outgroup than positive attitudes are. Results also demonstrated two mechanisms for increasing outgroup trust-through both direct and extended intergroup contact. These studies further our understanding of the psychological mechanisms underlying the formation of intergroup trust and behavior in areas of conflict. PMID:19106077

  15. Northern Security and Global Politics

    DEFF Research Database (Denmark)

    This book takes a comprehensive approach to security in the Nordic-Baltic region, studying how this region is affected by developments in the international system. The advent of the new millennium coincided with the return of the High North to the world stage. A number of factors have contributed...... strategic environment. This book will be of much interest to students of Nordic and Baltic politics, international security, foreign policy and IR....... to the increased international interest for the northern part of Europe: climate change resulting in ice melting in Greenland and the Arctic, and new resources and shipping routes opening up across the polar basin foremost among them. The world is no longer "unipolar" and not yet "multipolar," but...

  16. Rapid Rejuvenation of the Source of a Backarc Sheeted Magmatic Complex (Torres del Paine, Patagonia): Evidence From Hf isotopes in Zircon

    Science.gov (United States)

    Ewing, T. A.; Muntener, O.; Leuthold, J.; Chiaradia, M.; Baumgartner, L. P.; Putlitz, B.

    2014-12-01

    The Miocene Torres del Paine intrusive complex (TPIC) in Patagonia is a spectacularly exposed example of a bimodal shallow crustal laccolith, made up of a sill complex and a subvertical feeder system. The TPIC was emplaced in a back-arc setting, but slightly older arc-related intrusive units in this area testify to an earlier shift from an arc to a backarc setting. The entire ~88 km3 main complex was emplaced over short time scales of 162 ± 11 ka between ~12.4 and 12.6 Ma, with mafic units from the feeder zone found to be older than mafic units from the sill complex1,2. We aim to assess whether successive pulses of mafic magmatism can tap different geochemical reservoirs in sheeted magmatic complexes emplaced on such short timescales. Hf isotope compositions of individual zircons from mafic units from both the feeder zone and the sill complex were determined by solution MC-ICPMS. Zircons from all units have Hf isotope compositions that indicate a slightly enriched mantle source. Zircons from the mafic sill complex units have higher (more juvenile) initial ɛHf than zircons from feeder zone mafic units. The shift towards more depleted Hf isotope compositions in the sill complex units, which are younger, demonstrates the rapid input of new juvenile material into the source region between ~12.6 Ma and ~12.5 Ma. A similar shift is also seen in bulk rock Nd and Sr isotope data for related samples3. The Hf isotope data demonstrate that significant variability in source geochemistry is possible for sheeted magmatic complexes built up on very short timescales. Analysis of zircons from a range of dikes and intrusive bodies external to the main Torres del Paine complex, with ages that span ~12-29 Ma, will provide a more complete picture in time and space of the geochemical evolution of this magmatic system as it switches between an arc and backarc setting. 1Leuthold et al., 2012, EPSL, 325: 85-92 2Michel et al., 2008, Geology, 36: 459-462 3Leuthold et al., 2013, JPET, 54

  17. 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

  18. Tamaño corporal y temperatura ambiental en poblaciones cazadoras recolectoras del Holoceno tardío de Pampa y Patagonia

    Directory of Open Access Journals (Sweden)

    Béguelin, Marien

    2010-01-01

    Full Text Available El objetivo de este trabajo es describir los patrones de variación del tamaño corporal de las poblaciones del Holoceno tardío de Pampa y Patagonia Continental con el fin de discutir los procesos evolutivos que los habrían modelado. La hipótesis nula indica la acción de procesos evolutivos aleatorios y la alternativa plantea la acción de procesos no aleatorios, como la selección direccional o fenómenos de plasticidad fenotípica relacionados con la temperatura. Se combinaron métodos comparativos espaciales (correlación simple y partición de la variación con aquellos derivados de la genética cuantitativa (análisis de tasa de divergencia. Asimismo, se evaluó la correspondencia con expectativas biológicas derivadas de estudios experimentales. Las dimensiones del fémur fueron utilizadas como proxies del tamaño a través de variables morfométricas tradicionales. Los resultados indican un ajuste a un gradiente nortesur que se acopla al gradiente climático en el mismo sentido: a medida que aumenta la latitud, disminuye la temperatura y aumenta el tamaño, rechazando la hipótesis nula. Se explican las diferencias en tamaño principalmente por la interacción entre ambiente y espacio, interpretando un efecto común de ambas variables. El patrón descrito se ajusta a un modelo de aumento del tamaño, que implica una reducción de la pérdida de calor a partir de la disminución de la proporción superficie/ volumen. Por lo tanto, la divergencia en el tamaño corporal con el clima podría explicarse como resultado de la selección direccional vinculada a las bajas temperaturas, incrementándose el tamaño medio de los individuos con la disminución de la temperatura.

  19. Case studies: Northern Saskatchewan, Canada

    International Nuclear Information System (INIS)

    Northern Saskatchewan comprises an area of about 350 000 km2. In 1951 the population was 11 000 people but by 2003 it was approaching 40 000, of whom about 87% are aboriginal, consisting of either First Nations or Metis people. The first uranium mining area developed in northern Saskatchewan was Uranium City, north of Lake Athabasca. These first mines started production in the early 1950s. Of the 10 producing mines, only Eldorado Nuclear remained in operation after 1965. The development of Uranium City, including better services such as a hospital, drew some aboriginals into the area. There was some aboriginal employment in the early mines but, with few exceptions, these employees only stayed a short time. The mining companies developed training programmes to prepare aboriginals for regular, wage earning jobs. This included lifestyle training such as how to manage personal finances. Further extensive training programmes were required on the job to help these employees become fully contributing members of the workforce, who could advance in their jobs, expand their job opportunities and earnings, and in order to reduce turnover. The question of accommodating mine staff is a complex one, including several options. The first option, a company town, can be developed adjacent to the mine site. It is owned by the company and accommodates everyone who works at the mine and in its service industries. This can result in lower cost accommodation for mine staff with the benefit of no personal capital investment that cannot be recouped after mine closure. The capital cost to the mining company is higher; there is an administrative cost to managing and maintaining many houses, apartments and bunkhouses, and the decommissioning problem at the end of mine life is bigger. Initial developments in northern Saskatchewan were based on the company town concept. At the time there were 25 or more advanced exploration projects in the Uranium City area, 10 of which developed into producing

  20. Bioactive compounds from northern plants.

    Science.gov (United States)

    Hohtola, Anja

    2010-01-01

    Northern conditions are characterised by long days with much light and low temperatures during the growing season. It has been chimed that herbs and berries grown in the north are stronger tasting compared to those of southern origin. The compounds imparting aroma and color to berries and herbs are secondary metabolites which in plants mostly act as chemical means of defense. Recently, the production of secondary metabolites using plant cells has been the subject of expanding research. Light intensity, photoperiod and temperature have been reported to influence the biosynthesis of many secondary metabolites. Native wild aromatic and medicinal plant species of different families are being studied to meet the needs of raw material for the expanding industry of e.g., health-promoting food products known as nutraceutics. There are already a large number of known secondary compounds produced by plants, but the recent advances in modern extraction and analysis should enable many more as yet unknown compounds to be found, characterised and utilised. Rose root (Rhodiola rosea) is a perennial herbaceous plant which inhabits mountain regions throughout Europe, Asia and east coastal regions of North America. The extract made from the rhizomes acts as a stimulant like the Ginseng root. Roseroot has been categorized as an adaptogen and is reported to have many pharmacological properties. The biologically active components of the extract are salitroside tyrosol and cinnamic acid glycosides (rosavin, rosarin, rosin). Round-leaved sundew (Drosera rotundifolia L.) has circumboreal distribution. It inhabits nutrient-poor, moist and sunny areas such as peat bogs and wetlands. Sundew leaves are collected from the wild-type for various medicinal preparations and can be utilized in treating e.g., as an important "cough-medicine" for different respiratory diseases. The antimicrobial activity of extracts of aerial parts against various bacteria has been investigated. Drosera produces

  1. Los depósitos de oro y plata vinculados al magmatismo jurásico de la Patagonia: revisión y perspectivas para la exploración

    OpenAIRE

    2008-01-01

    La importancia del magmatismo jurásico de la Patagonia con relación a mineralizaciones de Au-Ag, ha sido reconocida desde hace menos de 20 años y al presente se definieron recursos por más de 700 t de Au equivalente contenido, en tres depósitos de clase mundial (>100 t AuEq contenido), algunos depósitos menores y numerosos prospectos en exploración. Se alojan en rocas volcánicas y volcano-sedimentarias jurásicas (o más antiguas), silíceas y mesosilíceas generadas en ambientes de arco y retro-...

  2. Análisis de las fracciones inorgánica y orgánica de pinturas rupestres y pastas de sitios arqueológicos de la Patagonia Septentrional argentina

    Directory of Open Access Journals (Sweden)

    María Teresa BOSCHÍN

    2013-05-01

    Full Text Available Se presentan los primeros resultados de una línea de trabajo que se apoya en los análisis químicos para determinar los componentes inorgánicos y orgánicos presentes en muestras de pinturas rupestres y de residuos de pintura (pastas recogidos en excavaciones arqueológicas. El objetivo es elucidar los procesos de trabajo y los conocimientos que estuvieron disponibles para las sociedades indígenas que habitaron los sectores central y occidental de la Patagonia septentrional argentina con posterioridad al undécimo siglo de nuestra era y hasta finales del siglo XIX. Nos interesa conocer las “recetas” de los talleres prehispánicos y determinar diferencias regionales y/o cronológicas.

  3. Saturación del carbonato de calcio en un área de cultivo de mitílidos en el Seno Reloncaví, Patagonia norte, Chile

    Directory of Open Access Journals (Sweden)

    Emilio Alarcón

    2015-05-01

    Full Text Available Se realizaron mediciones de temperatura, salinidad, alcalinidad total y carbono inorgánico disuelto del agua de mar superficial dentro de un área dedicada a la producción de semillas de mitílidos en el Seno de Reloncaví, Patagonia norte, durante el otoño (mayo 2012 y el verano austral (enero 2013. Se determinó que el estado de saturación del carbonato de calcio (ΩCaCO3 dentro del área de estudio fue bajo (Ωaragonita < 2, inclusive con aguas superficiales "corrosivas" para el CaCO3 (i.e., aguas subsaturadas, Ω < 1, cuando aguas de baja salinidad (<28 y alcalinidad total (<1.800 μmol kg-1 fueron advectadas dentro del centro de producción en mayo de 2012. En enero 2013 la baja salinidad (<25 fue asociada a aguas de baja alcalinidad total (ca. 1700 μmol kg-1 provocando bajos niveles de Ωaragonita en aguas superficiales equilibradas totalmente con la atmósfera (i.e., 400 μatm. Así, se sugiere que eventos corrosivos para el CaCO3 (i.e., aguas subsaturads Ω < 1 pueden ser una condición frecuente en esta área de producción de mitílidos en la Patagonia norte. La potencial disminución en productividad de Mytilus chilensis asociados a la acidificación del océano (AO recientemente descrita por Navarro et al. (2013 y la detección de aguas corrosivas para el carbonato de calcio encontradas, sugieren la necesidad de incluir el monitoreo regular del sistema carbonatos como una variable clave para la evaluación de la capacidad de carga de este sistema de aguas interiores.

  4. Contribution of allochthonous organic carbon across the Serrano River Basin and the adjacent fjord system in Southern Chilean Patagonia: Insights from the combined use of stable isotope and fatty acid biomarkers

    Science.gov (United States)

    Lafon, Alejandra; Silva, Nelson; Vargas, Cristian A.

    2014-12-01

    Chilean Patagonia is characterized by an irregular geography involving many islands, peninsulas, channels, sounds and fjords, that prevent direct interaction between oceanic water masses and freshwater river discharges at the head of the continental fjords. In this paper, we evaluate the potential sources and composition of organic matter along the Serrano River basin and the adjacent channels and fjords in Southern Chilean Patagonia (51-52°S), as well as their importance for marine planktonic organisms. In spring of 2009, evidence of C:N ratio, δ13C, δ15N and fatty acids composition in particulate organic carbon (POC), surface sediment, soil, plankton, and vegetal tissue, as well some physical and chemical characteristics (i.e. salinity, dissolved oxygen, NO3-, NH4+, PO4-3, Si(OH)4), were measured in samples collected during the CIMAR 14 Fiordos oceanographic cruise. Significant differences in δ13C-POC were found between the terrestrial and marine environments but not within fjord stations. Along the fjord region, the high C:N ratio and depleted δ13C values in POC samples suggest that particulate organic matter (POM) in the upper level of the water column (0-10 m depth) is supported by different sources. Terrestrial organic carbon exported by rivers may constitute a significant subsidy, up to 70% based on two end-member mixing model, to the fjord ecosystem. Furthermore, terrestrial carbon might account for a significant percentage of the zooplankton body carbon, estimated both by using isotopic (∼24-61%) and fatty acid analysis (∼14-61%). Isotopic analyses in marine sediment samples suggest that POC seems to be decoupled from terrestrial-influenced surface sources at the fjord stations, and the contribution of surrounding vegetation seemingly unimportant for carbon export to the benthos. Local hydrographic and geomorphological characteristics might determine the presence of oceanographic frontal zones, which in turn might explain differences in carbon

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

    Directory of Open Access Journals (Sweden)

    Patricia María Méndez

    2009-01-01

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

  6. 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.

  7. Patrones de distribución espacial y temporal de floraciones de Alexandrium catenella (Whedon & Kofoid Balech 1985, en aguas interiores de la Patagonia noroccidental de Chile Spatial and temporal distribution patterns of blooms of Alexandrium catenella (Whedon & Kofoid Balech 1985, on inland seas of northwest Patagonia, Chile

    Directory of Open Access Journals (Sweden)

    CARLOS MOLINET

    2003-12-01

    Full Text Available La presencia del dinoflagelado tóxico Alexandrium catenella en las aguas interiores de la Patagonia noroccidental, fue registrada en la década de los 90. A partir de 1995 se iniciaron programas de monitoreo de fitoplancton orientados al seguimiento de este dinoflagelado y sus efectos sobre los mariscos en la Décima y Undécima Región de Chile, financiados por distintas instituciones. Esto permitió recolectar una importante base de datos, aunque incompleta en muchos aspectos debido a la independencia de objetivos de los diferentes estudios. En esta revisión se agruparon todos los datos disponibles para buscar patrones que ayuden a la formulación de hipótesis sobre la dispersión e incidencia espacial y temporal de A. catenella en esta amplia zona y mucho más habitada que la Duodécima Región. Inicialmente se recolectaron muestras mensuales y desde fines de 2000 semanales tanto de fitoplancton como de mariscos en un número de estaciones que varió cada año. Desde fines de 1995 al 2002 se registraron cuatro floraciones de A. catenella, con intensidad y distribución variable, observándose una expansión de la distribución geográfica de esta especie hacia el norte (desde aproximadamente 45° 47' S en 1996 a 42° S, Chiloé en 2002. Las cuatro floraciones registradas fueron marcadamente estacionales, concentradas entre los meses de enero a marzo y coincidieron con los máximos registros del veneno paralizante de los mariscos. Los datos analizados sugieren que el origen de las floraciones de A. catenella en las aguas interiores de la región estaría asociada a la presencia de bancos de quistes, cuyo ciclo de vida se expresa con una variación bianual debido a la variación en condiciones ambientales que favorecen la germinación de estos organismos. La influencia de oscilaciones en el océano adyacente que estarían afectando las características de circulación general de las aguas interiores y las características de la columna de

  8. Isotope hydrology in northern Chile

    International Nuclear Information System (INIS)

    Environmental isotope analyses were done on samples from aquifers in the Pampa del Tamarugal and the Salar de Atacama drainage basin in northern Chile. In the Pampa it is possible to delineate individual groundwater bodies on the basis of their 18O and deuterium contents and, in some cases, to relate these to specific recharge areas. A marked displacement from the meteoric water line indicates that river recharge is an important mechanism for groundwater renewal. Groundwater ages appear high at distance from the Andes and much of the water found in the Pampa may have to be treated as a non-renewable resource. The groundwaters, springs and rivers of the Salar de Atacama drainage basin vary between -6.09 and -8.06%. No difference between the different waters can be recognized and an evaporative isotope enrichment indicates that also here river recharge is an important process. Some groundwaters adjacent to the Salar are very salty but 18O and deuterium data show that these waters are not refluxed brines but simply salty freshwater. The 14C contents in groundwaters and springs are very low but their delta13C values are high. It is concluded that this is probably due to the uptake of volcanic CO2. 14C age dating is thus not possible unless the delta13C values of all possible carbon sources can be defined and the geochemical evolution of the groundwaters is better understood. (author)

  9. Bread ovens in Northern Oretania

    Directory of Open Access Journals (Sweden)

    García Huerta, Rosario

    2006-06-01

    Full Text Available This paper intends to bring to light an unusual type of domestic structure in the northern Oretania, namely the ovens used for the production of bread. The study of their distribution, as well as their dimensions and constructive features, indicates they are more complex structures, with collective or communal characters. At the same time, it gives us some knowledge of the internal organization of the main oritanian oppidas.

    Este artículo pretende dar a conocer un tipo de estructura doméstica poco habitual en la Oretania septentrional, como son los hornos destinados a la producción de pan. El análisis de su distribución, así como sus dimensiones y características constructivas, revela que se trata de estructuras más complejas, de carácter colectivo o comunal, lo que permite aproximarnos al conocimiento de la articulación interna de los principales oppida oretanos.

  10. Earthquake Damage, Northern Iran, June 21, 1990

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A magnitude 7.7 earthquake occurred in the Gilan Province between the towns of Rudbar and Manjil in northern Iran on Thursday, June 21, 1990. The event, the largest...

  11. Northern Pintail - Flight Path Telemetry [ds117

    Data.gov (United States)

    California Department of Resources — North-south flight paths of radio-tagged female northern pintails were monitored in a section of Highway 152 near Los Banos, California during 4 and 11 November and...

  12. Biological processes of the northern Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Madhupratap, M.; Parulekar, A.H.

    , increases in the abundances of microzooplankton may lead to higher standing stocks of mesozooplankton. Blooms of phytoplankton and swarms of zooplankton are common in the northern Indian Ocean and influence rates of particle fluxes into the ocean interiors...

  13. Northern California 36 arc-second DEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 36-second Northern California Elevation Grid provides bathymetric data in ASCII raster format of 36-second resolution in geographic coordinates. This grid is...

  14. Northern California 6 arc-second DEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 6-second Northern California Elevation Grid provides bathymetric data in ASCII raster format of 6-second resolution in geographic coordinates. This grid is...

  15. Permafrost Soils Database for Northern Alaska 2014

    Data.gov (United States)

    Arctic Landscape Conservation Cooperative — This database contains soil and permafrost stratigraphy for northern Alaska compiled from numerous project data files and reports. The Access Database has main data...

  16. CNMI Northern Island Bottomfish System (NIBS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Commonwealth of the Northern Mariana Islands (CNMI), Division of Fish and Wildlife (DFW) conducted a market sampling program that existed for a few years back...

  17. Requirements for neonatal cots. Northern Neonatal Network.

    OpenAIRE

    1993-01-01

    A prospective survey of activity in neonatal nurseries associated with 17 specialist maternity units delivering some 38,700 babies in the Northern region was undertaken during 1991. Data were collected concerning the numbers of babies requiring various forms of neonatal care, using a nursing dependency scale validated by work study. Facilities for prolonged high dependency care are partially decentralised in the Northern region, with a network of five units operating on a flexible and collabo...

  18. Examining Affordability Issues in Northern Ireland

    OpenAIRE

    Brown, L.; S. McGreal; Gibb, K.; Joe Frey; Frey, J.

    2007-01-01

    The paper explores the relationship between house price growth, income levels, investor activity and the effects on entrants to the housing market. It concentrates on the area of first time buyers to the market and the issues of affordability which are now becoming increasingly apparent in Northern Ireland. House prices in Northern Ireland have experienced unprecedented growth particularly in the last 12 months (37% in 2006 alone according to the University of Ulster Quarterly House Price Ind...

  19. The rock resources of the Northern Emirates

    OpenAIRE

    Mitchell, Clive; Styles, Michael

    2011-01-01

    The Rock Resources of the Northern Emirates The United Arab Emirates (UAE) has vast resources of limestone and hard rock in the northern Emirates. These are currently exploited by quarrying companies to produce construction aggregate and raw material for the manufacture of cement, with a small amount being used to produce rock wool, dimension stone and mineral filler. The demand by industry for higher value mineral products that could be produced from these resources is mostly met by impor...

  20. Displacing AIDS: therapeutic transitions in Northern Uganda

    OpenAIRE

    Wilhelm-Solomon, M. M.; Alexander, Jocelyn; Daley, Patricia

    2014-01-01

    This doctoral project, entitled 'Displacing AIDS: Therapeutic Transitions in Northern Uganda' examines the biosocial transitions engendered by the treatment of HIV, focusing on antiretroviral therapy (ART/ARV) interventions, and the ways these are intertwined with the social transitions of conflict, displacement and return. The research involved an inter-disciplinary qualitative study with internally displaced communities living with HIV in northern Uganda, during 10 months fieldwork between ...

  1. CO 2 fluid and silicate glass as monitors of alkali basalt/peridotite interaction in the mantle wedge beneath Gobernador Gregores, Southern Patagonia

    Science.gov (United States)

    Scambelluri, M.; Vannucci, R.; De Stefano, A.; Preite-Martinez, M.; Rivalenti, G.

    2009-01-01

    A suite of mantle-wedge amphibole + phlogopite-bearing spinel peridotite xenoliths in Plio-Pleistocene alkali basalts from Southern Patagonia (Gobernador Gregores, Santa Cruz Province, Argentina) contains carbonic fluid inclusions, glass and carbonate in several textural domains. Here we present a microstructural and fluid inclusion study showing that fluid (corresponding to pure CO 2) and glass post-date the hydrous mantle assemblage and formed soon before and/or during xenolith entrainement in the host alkali basalt. The high densities preserved by a number of CO 2 inclusions indicate that fluid infiltration took place at mantle depths. The low densities pertaining to the majority of analyzed fluid inclusions derive from inclusion re-equilibration during xenolith ascent. Glass occurs in reaction haloes around clinopyroxene, amphibole and phlogopite, where it hosts microlites of new pyroxene, olivine and locally carbonate. Glass veins cut the mantle minerals and locally contain primary carbonate. Glasses vary widely in composition depending on the textural domains and attain Si- and alkali-rich compositions (SiO 2 = 47.0-68.3 wt.%; Na 2O + K 2O = 5.8-12.2 wt.%). Incompatible trace element patterns of glasses in anhydrous xenoliths are closely similar to those of the host alkali basalts, whereas the compositions of interstitial and vein glasses in the hydrous xenoliths indicate that a compositional control has been exerted by the local mineral assemblage (mainly amphibole). The δ18O values of carbonate from the glass pockets and veins in the xenoliths, as well as of carbonate globules and amygdales in the host basalts are in the range 19.62 to 21.04‰. Corresponding δ13C values are - 9.25 to - 10.12‰ and - 7.59 to - 9.32‰, respectively. These values are very different from those of primary carbonatites and the δ18O values clearly exceed those expected for minerals and glasses from mantle assemblages. The similarity of isotopic ratios of carbonates from both

  2. 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

  3. El mito de pristinidad y los usos efectivos del territorio de la región de Magallanes, Patagonia Chilena: Forestal, minería y acuicultura

    Directory of Open Access Journals (Sweden)

    Inostroza, Luis

    2015-06-01

    Full Text Available The current classification methods of land use in remote regions have two serious limitations. The first is the conceptual mixture between land uses and covers, which does not reflect the actual direct use of land. A second limitation is the absence of important uses such as tourism, aquaculture and mining, which impose significant pressures on fragile territories. This paper presents a land use classification method developed specifically for the region of Magellan in the extreme south of Chile. It is a land use classification wide and conceptually clear, which allows an effective determination of the range of land exploitations in Patagonia, determining which areas are used and which remain unused. The method is based entirely on a GIS and is a key input for improving land management. The analysis shows a high percentage of direct use, contrary to the existing pristine perception, which imposes significant challenges for current land management strategies.Los métodos de clasificación de usos del suelo en regiones remotas presentan dos serias limitaciones. La primera es la mixtura conceptual de usos con coberturas que no refleja el uso efectivo del territorio. Una segunda limitación es la ausencia de usos importantes como turismo, acuicultura y minería, que imponen importantes presiones sobre territorios frágiles. Este trabajo presenta un método para determinar los usos territoriales en la región de Magallanes en el extremo austral de Chile. Se trata de una clasificación de usos del suelo elaborada específicamente para este territorio, conceptualmente clara y amplia, que permite establecer el alcance efectivo de las explotaciones territoriales, determinando qué territorios son utilizados y cuales permanecen sin uso. El método está basado íntegramente en un SIG y constituye un insumo clave para mejorar la gestión territorial. El análisis refleja un alto porcentaje de uso directo, contrario a la percepción de pristinidad existente

  4. Viral diseases of northern ungulates

    Directory of Open Access Journals (Sweden)

    K. Frölich

    2000-03-01

    Full Text Available This paper describes viral diseases reported in northern ungulates and those that are a potential threat to these species. The following diseases are discussed: bovine viral diarrhoea/mucosal disease (BVD/MD, alphaherpesvirus infections, malignant catarrhal fever (MCF, poxvirus infections, parainfluenza type 3 virus infection, Alvsborg disease, foot-and-mouth disease, epizootic haemorrhage disease of deer and bluetongue disease, rabies, respiratory syncytial virus infection, adenovirus infection, hog-cholera, Aujeszky's disease and equine herpesvirus infections. There are no significant differences in antibody prevalence to BVDV among deer in habitats with high, intermediate and low density of cattle. In addition, sequence analysis from the BVDV isolated from roe deer (Capreolus capreolus showed that this strain was unique within BVDV group I. Distinct BVDV strains might circulate in free-ranging roe deer populations in Germany and virus transmission may be independent of domestic livestock. Similar results have been obtained in a serological survey of alpha-herpesviruses in deer in Germany. Malignant catarrhal fever was studied in fallow deer (Cervus dama in Germany: the seroprevalence and positive PCR results detected in sheep originating from the same area as the antibody-positive deer might indicate that sheep are the main reservoir animals. Contagious ecthyma (CE is a common disease in domestic sheep and goats caused by the orf virus. CE has been diagnosed in Rocky Mountain bighorn sheep (Ovis canadensis, mountain goats (Oreamnos americanus, Dall sheep (Ovis dalli, chamois (Rupkapra rupi-capra, muskox {Ovibos moschatus and reindeer (Rangifer tarandus. Most parainfluenza type 3 virus infections are mild or clinically undetectable. Serological surveys in wildlife have been successfully conducted in many species. In 1985, a new disease was identified in Swedish moose (Alces alces, designated as Alvsborg disease. This wasting syndrome probably

  5. Stratigraphy of the Martian northern plains

    Science.gov (United States)

    Tanaka, K. L.

    1993-01-01

    The northern plains of Mars are roughly defined as the large continuous region of lowlands that lies below Martian datum, plus higher areas within the region that were built up by volcanism, sedimentation, tectonism, and impacts. These northern lowlands span about 50 x 10(exp 6) km(sup 2) or 35 percent of the planet's surface. The age and origin of the lowlands continue to be debated by proponents of impact and tectonic explanations. Geologic mapping and topical studies indicate that volcanic, fluvial, and eolian deposition have played major roles in the infilling of this vast depression. Periglacial, glacial, fluvial, eolian, tectonic, and impact processes have locally modified the surface. Because of the northern plains' complex history of sedimentation and modification, much of their stratigraphy was obscured. Thus the stratigraphy developed is necessarily vague and provisional: it is based on various clues from within the lowlands as well as from highland areas within and bordering the plains. The results are summarized.

  6. Earthquake hazard analysis in northern Egypt

    International Nuclear Information System (INIS)

    Earthquake activity and seismic hazard analysis are important components of the seismic aspects for very essential structures such as major dams and nuclear power plants. Setting of nuclear power plants becomes of increasing important in northern Egypt with the commitment towards promoting nuclear electric generation. Therefore, the annual seismic hazard maps with non-exceedence probability of 80%, 85% and 90% are given. These maps show that northern Egypt is severely affects by earthquakes from potential sources around Sinai peninsula. Three sites (Nile Delta, Cairo, and Ismailia region) have been chosen to estimated the earthquake hazard in more detailes to serve as a basic parameter to the safety factor of different projects in these regions. A seismic safety factor of intensity 8.5 should be considered in designing the vital projects in northern Egypt. (author)

  7. Climate Impacts on Northern Canada: Regional Background

    Energy Technology Data Exchange (ETDEWEB)

    Prowse, Terry D.; Peters, Daniel L. (Water and Climate Impacts Research Centre, Environment Canada, Dept. of Geography, Univ. of Victoria, Victoria, BC (Canada)). e-mail: terry.prowse@ec.gc.caa; Furgal, Chris (Indigenous Environmental Studies Program, Trent Univ., Peterborough, ON (Canada)); Bonsal, Barrie R. (National Water Research Inst., National Hydrology Research Centre, Environment Canada, Saskatoon, SK (Canada))

    2009-07-15

    Understanding the implications of climate change on northern Canada requires a background about the size and diversity of its human and biogeophysical systems. Occupying an area of almost 40% of Canada, with one-third of this contained in Arctic islands, Canada's northern territories consist of a diversity of physical environments unrivaled around the circumpolar north. Major ecozones composed of a range of landforms, climate, vegetation, and wildlife include: Arctic, boreal and taiga cordillera; boreal and taiga plains; taiga shield; and northern and southern Arctic. Although generally characterized by a cold climate, there is an enormous range in air temperature with mean annual values being as high as -5 deg C in the south to as low as -20 deg C in the high Arctic islands. A similar contrast characterizes precipitation, which can be >700 mm y-1 in some southern alpine regions to as low as 50 mm y-1 over islands of the high Arctic. Major freshwater resources are found within most northern ecozones, varying from large glaciers or ice caps and lakes to extensive wetlands and peat lands. Most of the North's renewable water, however, is found within its major river networks and originates in more southerly headwaters. Ice covers characterize the freshwater systems for multiple months of the year while permafrost prevails in various forms, dominating the terrestrial landscape. The marine environment, which envelops the Canadian Arctic Archipelago, is dominated by seasonal to multiyear sea ice often several meters thick that plays a key role in the regional climate. Almost two-thirds of northern Canadian communities are located along coastlines with the entire population being just over 100 000. Most recent population growth has been dominated by an expansion of nonaboriginals, primarily the result of resource development and the growth of public administration. The economies of northern communities, however, remain quite mixed with traditional land

  8. Biogeochemical processes in the northern Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Gaye-Haake, B.; Guptha, M.V.S.; Murty, V.S.N.; Ittekkot, V.

    Indian rivers dominate sedimentation processes in the Bay of Bengal and can reach the 1845–1847 Northern Indian Ocean The majority of contributions deals with results from bilateral programs such as the long-term Indo-German program on ‘‘Particle fluxes... in the northern Indian Ocean’’, and from national research programs of India and Germany con- ducted as a contribution to the international JGOFS Process Study in the Arabian Sea. Addi- tional contributions cover research carried out within India’s Polymetallic...

  9. Rural telemedicine project in northern New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Zink, S.; Hahn, H.; Rudnick, J.; Snell, J.; Forslund, D. [Los Alamos National Lab., NM (United States); Martinez, P. [Northern New Mexico Community Coll., Espanola, NM (United States)

    1998-12-31

    A virtual electronic medical record system is being deployed over the Internet with security in northern New Mexico using TeleMed, a multimedia medical records management system that uses CORBA-based client-server technology and distributed database architecture. The goal of the NNM Rural Telemedicine Project is to implement TeleMed into fifteen rural clinics and two hospitals within a 25,000 square mile area of northern New Mexico. Evaluation of the project consists of three components: job task analysis, audit of immunized children, and time motion studies. Preliminary results of the evaluation components are presented.

  10. Northern Jutland as an Intertextual Location

    DEFF Research Database (Denmark)

    Hansen, Kim Toft; Christensen, Jørgen Riber

    2015-01-01

    With the region of Northern Jutland as a concrete case, the discussion about peripheral areas in Denmark will be contextualized in Augé's theory about anthropological places and non-places, and his theory will be expanded constructively and critically with the concept of intertextual locations. The...... Northern Jutland can be regarded as a location potential of this kind, which is can promote film and media production in the region. An important point in this connection will be that there may be a local and peripheral wish to become an intertextual location because this may lead to regional development...

  11. Seromonitoring of rinderpest in Northern Uganda

    International Nuclear Information System (INIS)

    Seromonitoring of rinderpest was carried out in the Northern region of Uganda which covers the sub-regions of West Nile, Northern Uganda, and N.E. Uganda. Three thousand nine hundred ninety two serum samples were collected and tested using the competitive ELISA. The antibody prevalence ranged from 21% to 81%. Although the areas at high risk of rinderpest had low antibody levels their neighbors seem to be establishing immune barrier. Since all the sampled districts were equally supported to carry out vaccination, this survey has emphasized the usefulness of sero monitoring in assessing the success of vaccination programmes. (author). 3 refs, 3 figs, 2 tabs

  12. Northern Land Council v. the Commonwealth

    International Nuclear Information System (INIS)

    The Ranger Project Area in the Northern Territory contains deposits of uranium. By section 5 of the Atomic Energy Amendment Act (No. 2) 1980 the assignment of an agreement between the Commonwealth and joint venturers for the conduct of uranium mining was authorised. The Northern Land Council, representing Aboriginal interests, challenged the validity of the section. It was held that the section was valid. The Council also submitted that, although it had entered into an agreement with the Commonwealth in 1978, the agreement was void or voidable

  13. Aisle-truss houses of Northern Jutland

    DEFF Research Database (Denmark)

    Eybye, Birgitte Tanderup

    2014-01-01

    The aisle-truss houses of Northern Jutland were built under hard conditions, such as harsh climate and scarce resources. Hence, the aisle-truss houses display a number of resource-saving and sustainable building principles, including the arcade construction and the use of passive energy strategies......, which make them relevant to research. This paper investigates resource-saving and sustainable principles in the aisle-truss houses of Thy, Northern Jutland. General features as well as three cases of the one-wing dwelling aisle-truss houses are studied. The aim is to improve the understanding of aisle...

  14. Northern and Southern RE Groups Ended Resultlessly

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In September 2002, "Organizing of National Rare EarthEnterprises Group" which was delivered by original NationalEconomy & Trade Committee and original National PlanningCommittee, Ministry of Finance P.R.C, Ministry of Land &Resource P.R.C. and Ministry of Foreign Economy & Trade,was approved by the State Council of P.R.C. to organizeSouthern and Northern Rare Earth Groups. On October 30,2002, China Northern RE Group Co., Ltd Preparation Teamheld the foundation convention in Baotou, which drew thecurtain of ...

  15. Petrology of continental pyroclastic and epiclastic sequences in the Chubut Group (Cretaceous: Los Altares-Las Plumas area, Chubut, Patagonia Argentina

    Directory of Open Access Journals (Sweden)

    Marcelo Manassero

    2000-07-01

    Full Text Available La petrología de secuencias piroclásticas y epiclásticas en el Grupo Chubut (Cretácico: área de Los Altares-Las Plumas, Patagonia Argentina. Las sucesiones volcaniclásticas de la Formación Cerro Barcino (Grupo Chubut, Aptiano-Cenomaniano, afloran en ambas márgenes del río Chubut con 200 m de espesor. Los miembros medio: Cerro Castaño (sineruptivo, 90 m y superior, Las Plumas (intereruptivo, 110 m son descritos con el mapeo fotogeológico, estudios de campo y laboratorio (mineralógico, petrográfico y geoquímico. Las paleocorrientes se orientan hacia el noreste (Cerro Castaño y hacia el norte (Las Plumas. Se ha reconocido, por primera vez, un límite erosivo en la base del Miembro Las Plumas. Las rocas piroclásticas presentan vitroclastos planares, curviplanares, ramificados y en forma de Y, y pumicitas fibrosas. Los depósitos epiclásticos incluyen fragmentos de tobas vítreas, con pigmentación hematítica (Las Plumas. Los vitroclastos están alterados, por procesos diagenéticos, a arcillas (esmectita y rara illita o a zeolitas. En el Miembro Cerro Castaño predomina analcima, asociada a clinoptilolita, mientras que en el Miembro Las Plumas la clinoptilolita se asocia a analcima y mordenita. La sedimentación piroclástica (lluvias de cenizas ocurrió en extensas llanuras onduladas, donde había discretos canales arenosos. En la base del Miembro Las Plumas, la aparición de valles amplios poco profundos, por los cuales corrieron ríos entrelazados que depositaron conglomerados y areniscas, está relacionada a actividad tectónica-climática. Las erupciones fueron del tipo magmático explosivo y los intensos procesos de fragmentación estuvieron relacionados a magmas viscosos, ricos en volátiles de composición riolítica-dacítica. La abundancia de vitroclastos planares, curviplanares y ramificados finos, sugieren que el centro explosivo se localizaba a una distancia aproximada de 500 km probablemente hacia el oeste

  16. Regional health library service in northern Ireland.

    OpenAIRE

    Crawford, D S

    1990-01-01

    The regional medical library service provided to physicians, hospitals, nurses, social workers, and health care administrators throughout Northern Ireland by the Queen's University of Belfast is described. A brief outline of the National Health Service in the United Kingdom is given, and the library service is described in terms of collections, cataloging, interlibrary loan, and reference.

  17. Applied Indigenous Studies at Northern Arizona University.

    Science.gov (United States)

    Trosper, Ronald L.

    2001-01-01

    The Applied Indigenous Studies program at Northern Arizona University aims to prepare American Indian students to assume tribal leadership roles. Its location in the College of Ecosystem Science and Management emphasizes its land-oriented and applied focus. The program's development, core courses, and academic requirements for bachelors degrees…

  18. Forest Fire History in the Northern Rockies

    OpenAIRE

    Arno, Stephen F.

    1980-01-01

    Recent fire-scar studies in the northern Rocky Mountains have documented forest fire history over the past few centuries. They reveal that in some forest types fire maintained many-aged open stands of seral trees. In other types, major fires caused replacement of the stands. Often, however, fires burned at variable intensities, creating a mosaic of stands differing in composition and structure.

  19. Northern Ireland: post-conflict education model?

    Directory of Open Access Journals (Sweden)

    Paul Nolan

    2006-07-01

    Full Text Available Northern Ireland’s Good Friday Agreement of 1998 calledfor “initiatives to facilitate and encourage integratededucation” but progress has been painfully slow. Only 5%of the total school population are in integrated schools(those bringing together students and staff from boththe Protestant and Catholic traditions. Only 1.4% of theadult population has experienced integrated schooling.

  20. The Times and the Northern Ireland Conflict

    Directory of Open Access Journals (Sweden)

    Zouhaïr Abassi

    2006-03-01

    Full Text Available Abstract: In societies in conflict the role of the media is supposed to be neutral and to report conflicts fairly and with balanced analyses. By their public debates on conflicts they are also supposed to take part in pacifying societies and in helping to bring peace. Cottle (1997, for instance, explained that even though some findings related to the British media and its reporting of the Northern Ireland conflict were relevant, he argued that they needed revision. Consequently, he proposed new paradigms of media studies. Elliott (1977 and Curtis(1996 showed that the British media concentrated on violence in general and on republican violence in particular. Moreover, they argued that the British media neglected social and political contexts in their reporting of the conflict. The aim of this paper is then to examine some aspects of how the British media cover the Northern Ireland conflict. We studied the coverage of the Northern Ireland conflict by The (London Times (1990-1995. We used a discourse analysis method to study the paper’s discourse structure in its representation of the Northern Ireland conflict.

  1. Winter cooling in the northern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    PrasannaKumar, S.; Prasad, T.G.

    forcing that leads to the observed high productivity during winter in the northern Arabian Sea. The weak northerly winds and increased solar insolation during the inter-monsoon period, led to the development of a highly stratified upper layer with warm sea...

  2. Mining and energy in the Northern Territory

    International Nuclear Information System (INIS)

    Included in this book is a section on each of the major minerals of present or future importance to the Northern Territory. Brief details of the uranium mining projects at Nabarlek, Ranger, Koongarra and Jabiluka in the Alligator Rivers regions are given. Subjects such as environmental protection, Aboriginal land rights and the geology of the area are also considered

  3. Controlling human oesophagostomiasis in northern Ghana

    NARCIS (Netherlands)

    Ziem, Juventus Benogle

    2006-01-01

    This thesis describes aspects of the epidemiology and attempts to control infection and pathology due to the nematode parasite Oesophagostomum bifurcum . In northern Ghana and Togo O. bifurcum is an important parasite of humans; elsewhere it is predominantly seen as a parasite of non-human primates.

  4. Northern oil and gas - annual report 1997

    International Nuclear Information System (INIS)

    Oil and gas resources on crown lands north of 60 degrees latitude are managed by the federal government under the Northern Oil and Gas Directorate of the Department of Indian and Northern Affairs and Northern Development. Notable activities in 1997 included the re-introduction in Parliament of the Canada-Yukon Oil and Gas Accord of 1993. The proposed legislation aims to transfer power to the Yukon government by 1998, making it responsible for administration and regulation of onshore oil and gas exploration and development in the territory. In 1997, new gas reserves were uncovered in the southern Northwest Territories. Thirteen new wells were drilled and about $45 million in exploration work was carried out. This included work by Inuvialuit Petroleum Corp., in the Ikhil gas field in the Mackenzie Delta which could end Inuvik's dependency on imported petroleum products. A statistical overview of the oil and gas activities under Northern Oil and Gas was summarized and broken down by region. 11 refs

  5. From Poetry to Music: "Northern Lullaby"

    Science.gov (United States)

    Cardany, Audrey Berger

    2011-01-01

    Nancy White Carlstrom's children's book, "Northern Lullaby," conjures through poetry the beauty of the Alaskan landscape in the evening. The book provides an opportunity for music teachers to help their students transform text and visual images to music. The author describes connections for reading comprehension in the general music classroom and…

  6. 76 FR 31299 - Northern New Mexico Resource Advisory Committee

    Science.gov (United States)

    2011-05-31

    ... Forest. BILLING CODE 3410-11-P ... Forest Service Northern New Mexico Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Correct FR Doc. 2011-12588; Notice of meeting. SUMMARY: The Northern New Mexico Resource...

  7. Discussion on several geological problems and uranium metallogeny on northern border of northern China block (platform)

    International Nuclear Information System (INIS)

    According to the informations from the satellite image and the field investigation the following geological events on the northern border of the Northern China Block are recognized and confirmed, duch as suture zones between blocks, folding-reversed fault zones, back-arc collision zones (faulted zones), transitional zone between platform and geosyncline, magmatic are and the double sturcture composed of NNE trend magmatic active belt and fault-depression belts (basins) of Yenshan-Ximalaya age. On thsee bases the following problems, such as the unique structural environment of uranium mineralization related to abyssal magmatic rocks and Yenshan magmatic active zone (including volcanic belt) on the northern border of the Northern China Block, the metallogenetic modes for urnaium deposits of 'magmatic type' and 'neutralized surface type' in fault-depression zone and the classification of uranium metallogenetic belts and the criteria for such classification are studied and discussed. Several uranium deposits are given for illustrations

  8. Canada: Native Land Rights and Northern Development. IWGIA Document 26.

    Science.gov (United States)

    Cumming, Peter A.

    Presenting the critical elements for a new and meaningful relationship between the Inuit and the emerging industrial society of Northern Canada, this publication includes: (1) Canada as a Nation State and Northern Development; (2) Northern Development and Institutions in Decision-Making; (3) The Northwest Territories and Yukon Territory as…

  9. 77 FR 35958 - Northern Natural Gas Company; Notice of Application

    Science.gov (United States)

    2012-06-15

    ... Energy Regulatory Commission Northern Natural Gas Company; Notice of Application Take notice that on May 30, 2012, Northern Natural Gas Company (Northern), 1111 South 103rd Street, Omaha, Nebraska 68124... regulations and section 7(b) of the Natural Gas Act, to abandon by sale to DKM Enterprises, LLC (DKM)...

  10. 75 FR 35779 - Northern Natural Gas Company; Notice of Application

    Science.gov (United States)

    2010-06-23

    ... Energy Regulatory Commission Northern Natural Gas Company; Notice of Application June 16, 2010. Take notice that on June 2, 2010, Northern Natural Gas Company (Northern), 1111 South 103rd Street, Omaha... Natural Gas Act, for a certificate of public convenience and necessity authorizing the increase...

  11. 78 FR 51716 - Northern Natural Gas Company; Notice of Application

    Science.gov (United States)

    2013-08-21

    ... Energy Regulatory Commission Northern Natural Gas Company; Notice of Application Take notice that on August 1, 2013, Northern Natural Gas Company (Northern), 1111 South 103rd Street, Omaha, Nebraska 68124, filed an application pursuant to section 7(c) of the Natural Gas Act and part 157 of the...

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Uranium and thorium deposits of Northern Ontario

    International Nuclear Information System (INIS)

    This, the second edition of the uranium-thorium deposit inventory, describes briefly the deposits of uranium and/or thorium in northern Ontario, which for the purposes of this circular is defined as that part of Ontario lying north and west of the Grenville Front. The most significant of the deposits described are fossil placers lying at or near the base of the Middle Precambrian Huronian Supergroup. These include the producing and past-producing mines of the Elliot Lake - Agnew Lake area. Also included are the pitchblende veins spatially associated with Late Precambrian (Keweenawan) diabase dikes of the Theano Point - Montreal River area. Miscellaneous Early Precambrian pegmatite, pitchblende-coffinite-sulphide occurrences near the Middle-Early Precambrian unconformity fringing the Lake Superior basin, and disseminations in diabase, granitic rocks, alkalic complexes and breccias scattered throughout northern Ontario make up the rest of the occurrences

  14. Cardiac surgical experience in northern Nigeria.

    Science.gov (United States)

    Nwiloh, J; Edaigbini, S; Danbauchi, S; Babaniyi, I; Aminu, M; Adamu, Y; Oyati, A

    2012-09-01

    A pilot study was undertaken to determine the feasibility of establishing a heart surgery programme in northern Nigeria. During three medical missions by a visiting US team, in partnership with local physicians, 18 patients with heart diseases underwent surgery at two referral hospitals in the region. Sixteen (88.9%) patients underwent the planned operative procedure with an observed 30-day mortality of 12.5% (2/16) and 0% morbidity. Late complications were anticoagulant related in mechanical heart valve patients and included a first-trimester abortion one year postoperatively, and a death at two years from haemorrhage during pregnancy. This has prompted us to now consider bioprosthetics as the valve of choice in women of childbearing age in this patient population. This preliminary result has further stimulated the interest of all stakeholders on the urgency to establish open-heart surgery as part of the armamentarium to combat the ravages of heart diseases in northern Nigeria. PMID:22453514

  15. Trace gas fluxes from northern peatlands

    Energy Technology Data Exchange (ETDEWEB)

    Moore, T. [McGill Univ., Montreal (Canada). Geography Dept.

    1996-12-31

    Peatlands cover large areas in northern environments: 1.1, 0.1 and 1.7 x 10{sup 4} km{sup 2} in Canada, Finland and the former Soviet Union, respectively. Interest has been generated into the role these extensive areas of peatlands play in controlling the chemistry of the atmosphere. In particular, it has become established that peatlands can be a source of methane (CH{sub 4}) and nitrous oxide (N{sub 2}O), and a sink of carbon dioxide (CO{sub 2}), the latter through the rates of plant production exceeding the rate of decomposition of plant material and peat. In this presentation the recent advances in trace gas flux measurements in northern peatlands are presented. (16 refs.)

  16. DISENGAGING FROM TERRORISM: A NORTHERN IRISH EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Neil Ferguson

    2016-03-01

    Full Text Available This article explores the disengagement and deradicalization experiences of Northern Irish loyalist paramilitaries from the Ulster Volunteer Force (UVF and Red Hand Commando (RHC. Interpretative phenomenological analysis was employed to develop an understanding of how the former combatants interpreted and made sense of their disengagement from violence extremism in Northern Ireland after the Belfast Agreement. The analysis of the interviews focusses around push and pull factors which either promote or hinder their ability to move away from violent extremism. The results find a resonance with recent research exploring disengagement and deradicalization processes with terror groupings across the globe and the ideological spectrum. The findings are discussed in relation to a number of topics, including the role of prison, barriers to disengagement, continued commitment and radicalization after desistence from violent extremism, the role of life changes in promoting disengagement and how organizational pressures contain and influence individual disengagement.

  17. Cardiac surgical experience in northern Nigeria

    OpenAIRE

    Nwiloh, J; Edaigbini, S; Danbauchi, S; Aminu, M.; Oyati, A; Babaniyi, I; Adamu, Y.

    2012-01-01

    Abstract A pilot study was undertaken to determine the feasibility of establishing a heart surgery programme in northern Nigeria. During three medical missions by a visiting US team, in partnership with local physicians, 18 patients with heart diseases underwent surgery at two referral hospitals in the region. Sixteen (88.9%) patients underwent the planned operative procedure with an observed 30-day mortality of 12.5% (2/16) and 0% morbidity. Late complications were anticoagulant related in m...

  18. New geoscience surveys in Northern Ireland

    OpenAIRE

    Young, Mike; Smyth, Dermot

    2005-01-01

    New regional geochemical and geophysical surveys are in progress in Northern Ireland. These will advance the development of the natural resource industry and provide a baseline of information against which to measure environmental change. Soils, stream-sediments and stream-waters are being sampled, according to the G-BASE standard of the British Geological Survey, and analysed by XRF and ICP. The airborne geophysical survey will be flown by a fixed-wing aircraft equipped with magnetometer, 25...

  19. Lithological control on soil chemistry, Northern Ireland

    OpenAIRE

    Ashton, Nicola; Pattrick, R. A. D.; J. R. Lloyd; B. E. van Dongen; Tye, A.

    2011-01-01

    The geological diversity of Northern Ireland provides a unique opportunity to investigate the effects of differing lithologies upon the (organic) geochemistry of overlying soils. This will aid the understanding of how this influences the microbial populations within the soil and their role in biochemical cycling. Whilst several factors contribute to the properties of developing soils, source rock is one of the major controls in determining chemistry and formation rate (Chengmin et al., 2...

  20. Ethno-botanical studies from northern Pakistan

    International Nuclear Information System (INIS)

    In this research paper efforts have been made to document the ethno-botanical knowledge of important plant species found in Northern Pakistan. It includes Thandiani, Galiat, Kaghan, Swat, Buner, Dir, Chitral and Northern Areas of Pakistan. The area has many climatic and vegetation zones or biomes. Locals residing in mountainous areas belonging to various ethnic groups are traditionally utilizing plants over many generations; these ethnic groups have their distinct life style, belief, traditions and cultural heritage. Plant collection and data regarding traditional uses in various areas of Northern Pakistan has been done periodically in different flowering /fruiting seasons. Locals of old age belonging to various ethnic groups were personally interviewed for establishing uses of plants. Photography is done for easy identification and habitat recognition. Collected plant specimens and seeds were preserved. Plant species were dried, mounted, identified and authenticated. Seventy six species were known to have traditional and ethno botanical uses. Plants have been utilized for many generations. Ethnic groups have distinct life style and have different economic uses for these plants. Due to unsustainable exploitation of natural habitats scarcity of drug plants has occurred. As consequence some species are depleting and may become extinct in near future, e. g. Morchella esculenta, Colchicum lueteum and Viola serpens are just a few of these. Although some sporadic information is available about the flora of this region but very little documented record of the ethno-botanically important plants has been established. It is expected that this research paper will be beneficial for students, researchers, farmers, foresters and general public. On the basis of data obtained it is concluded that ethno-botanical Flora of Northern Pakistan is quite rich and is diverse, due to the difference in altitude, climate and other topographic conditions. (author)

  1. Structural curiosity of the northern Istria

    OpenAIRE

    Ladislav Placer

    2005-01-01

    In northern Istria certain structural particularities exist that till now were not explained,and some of them not even known. They are all associated with underthrusting of the Adriatic microplate (Istra) under the Dinarides. The Rokava fault of cross-dinaricdirection was discovered that exerts an important influence on hydrographic pattern in this part of Istria. The cross-dinaric sinistral strike-slip faults above Glinščica stream (Rosandra) are of local importance only, since at Kastelec a...

  2. Pneumonic Plague Outbreak, Northern Madagascar, 2011

    OpenAIRE

    Richard, Vincent; Riehm, Julia M; Herindrainy, Perlinot; Soanandrasana, Rahelinirina; Ratsitoharina, Maherisoa; Rakotomanana, Fanjasoa; Andrianalimanana, Samuel; Holger C. Scholz; Rajerison, Minoarisoa

    2015-01-01

    Yersinia pestis, the causative agent of plague, is endemic to Madagascar, particularly to the central highlands. Although plague has not been previously reported in northern Madagascar, an outbreak of pneumonic plague occurred in this remote area in 2011. Over a 27-day period, 17 suspected, 2 presumptive, and 3 confirmed human cases were identified, and all 15 untreated 20 patients died. Molecular typing of Y. pestis isolated from 2 survivors and 5 Rattus rattus rat samples identified the Mad...

  3. Food irradiation - a Northern Ireland dimension

    International Nuclear Information System (INIS)

    Irradiation is a technology which has been exploited in a wide variety of industries ranging from sterilization of medical products and polymer modification to applications with respect to food. Whilst food irradiation has recently become a controversial subject, the process has been studied for many years. Many products could be irradiated to advantage and these need to be thoroughly investigated before final recommendations can be made as to the commercial feasibility and suitability of the processing technology in the Northern Ireland context

  4. Mobile rural youth in northern Ghana

    DEFF Research Database (Denmark)

    Gough, Katherine; Birch-Thomsen, Torben

    2016-01-01

    Young people in northern Ghana are growing up in a very different environment from their southern counterparts. While the south is the locus of the major cities, industries, and most important cash crops, the north is primarily rural with an agricultural base, much of it subsistence. This distinc...... to stop them from moving, their mobility should be seen as a potential source of capital and experience, which those who return can use to invest in farming or establishing an alternative business....

  5. LIVESTOCK PRICING IN THE NORTHERN KENYAN RANGELANDS

    OpenAIRE

    Barrett, Christopher B.; Chabari, Francis; Bailey, DeeVon; Coppock, D. Layne; Little, Peter D.

    2001-01-01

    This paper uses detailed, transactions-level data and a structural-heteroskedasticity-in-mean model to identify the determinants of livestock producer prices for pastoralists in the drylands of northern Kenya. The empirical results confirm the importance of animal characteristics, periodic events that predictably shift local demand or supply, and especially rainfall on the prices pastoralists receive for animals. Price risk premia are consistently negative in these livestock markets. The impo...

  6. Early millet use in northern China

    OpenAIRE

    Yang, Xiaoyan; Wan, Zhiwei; Perry, Linda; Lu, Houyuan; Wang, Qiang; Zhao, Chaohong; Li, Jun; XIE, FEI; Yu, Jincheng; Cui, Tianxing; Wang, Tao; Li, Mingqi; Ge, Quansheng

    2012-01-01

    It is generally understood that foxtail millet and broomcorn millet were initially domesticated in Northern China where they eventually became the dominant plant food crops. The rarity of older archaeological sites and archaeobotanical work in the region, however, renders both the origins of these plants and their processes of domestication poorly understood. Here we present ancient starch grain assemblages recovered from cultural deposits, including carbonized residues adhering to an early p...

  7. Sporotrichosis from the Northern Territory of Australia

    OpenAIRE

    Subedi, Shradha; Kidd, Sarah E.; Baird, Robert W.; Coatsworth, Nicholas; Ralph, Anna P

    2014-01-01

    We report three cases of lymphocutaneous infection caused by the thermally dimorphic fungus, Sporothrix schenckii from Australia's tropical Northern Territory. Two cases were acquired locally, making them the first to be reported from this region. All three cases presented with ulceration in the limb; however, the classical sporotrichoid spread was present only in the first two cases. Their occurrence within several weeks of each other was suggestive of a common source of environmental contam...

  8. New Economic Cycle in Northern Periphery

    OpenAIRE

    Marc-Urbain Proulx

    2014-01-01

    Within the vast northern periphery of Quebec, the annual capital almost doubled over the 2000s. This impulse of a new cycle of growth coincides with a slowdown in job creation. Such effects on the mode of development is part of a multi-dimensional and transitional movement within global peripheries requested to supply, of their raw materials, high urbanization in emerging economies. For this purpose in Quebec, the Nordic economic sectors of construction, extraction, processing, and services r...

  9. Northern Ireland regional breastfeeding peer support training

    OpenAIRE

    Public Health Agency

    2012-01-01

    This resource�has been produced for breastfeeding coordinators and breastfeeding peer support trainers who provide training for peer support volunteers. �� The resource has been distributed by PHA directly to those involved in breastfeeding peer support programmes in Northern Ireland. Further copies can be requested as applicable from Lesley Blackstock at: The CD supports delivery of eight peer support teaching sessions (two hours each), which meet Open College Net...

  10. t he Cluster Approach in northern Uganda

    OpenAIRE

    Jessica Huber; Birkeland, Nina M.

    2007-01-01

    The Norwegian Refugee Council (NRC) strongly believes that the Cluster Approach holds promise for improving the international response to internal displacement. The approach represents a serious attempt by the UN, NGOs, international organisations and governments to address critical gaps in the humanitarian system. We want this reform effort to succeed and to play an active role in northern Uganda to supportthe work of the clusters and improve their effectiveness.

  11. t he Cluster Approach in northern Uganda

    Directory of Open Access Journals (Sweden)

    Jessica Huber

    2007-12-01

    Full Text Available The Norwegian Refugee Council (NRC strongly believes that the Cluster Approach holds promise for improving the international response to internal displacement. The approach represents a serious attempt by the UN, NGOs, international organisations and governments to address critical gaps in the humanitarian system. We want this reform effort to succeed and to play an active role in northern Uganda to supportthe work of the clusters and improve their effectiveness.

  12. Can Turkey learn anything from Northern Ireland?

    OpenAIRE

    KAYA, Zeynep; Whiting, Matthew

    2013-01-01

    Recently a group of politicians and commentators from Turkey visited Northern Ireland to learn about its peace process and explore any lessons this might hold for the ongoing fragile negotiations between the Turkish government and the imprisoned leader of the Kurdistan Workers’ Party (PKK), Abdullah Öcalan. The visitors met with former rebels-turned-politicians from Sinn Féin as well as senior British and Irish political figures, in a trip that was endorsed by the Turkish Prime Minister, Rece...

  13. Spatial distribution of pingos in Northern Asia

    OpenAIRE

    G. Grosse; Jones, B M

    2010-01-01

    Pingos are prominent periglacial landforms in vast regions of the Arctic and Subarctic. They are indicators of modern and past conditions of permafrost, surface geology, hydrology and climate. A first version of a detailed spatial geodatabase of more than 6000 pingo locations in a 3.5 × 106 km2 region of Northern Asia was assembled from topographic maps. A first order analysis was carried out with respect to permafrost, landscape characteri...

  14. Wildfires in northern Siberian larch dominated communities

    International Nuclear Information System (INIS)

    The fire history of the northern larch forests within the permafrost zone in a portion of northern Siberia (∼66°N, 100°E) was studied. Since there is little to no human activity in this area, fires within the study area were mostly caused by lightning. Fire return intervals (FRI) were estimated on the basis of burn marks on tree stems and dates of tree natality. FRI values varied from 130 to 350 yr with a 200 ± 50 yr mean. For southerly larch dominated communities, FRI was found to be shorter (77 ± 20 yr at ∼ 61°N, and 82 ± 7 at 64°N), and it was longer at the northern boundary (∼71°) of larch stands (320 ± 50 yr). During the Little Ice Age period in the 16th–18th centuries, FRI was approximately twice as long those as recorded in this study. Fire caused changes in the soil including increases in soil drainage and permafrost thawing depth, and a radial growth increase to about twice the background value (with more than six times observed in extreme cases). This effect may simulate the predicted warming impact on the larch growth in the permafrost zone.

  15. Pacific Northern Gas Ltd. annual report 2002

    International Nuclear Information System (INIS)

    Pacific Northern Gas Ltd. operates in west-central and northeast British Columbia. The company delivers natural gas to customers through a transmission pipeline connected to Duke Energy system near Summit Lake, British Columbia. This report states that in 2002 financial results were disappointing. The company's net income in 2002 was lower than it was in 2001 ($4.6 million versus $5.7 million). In December 2002, Pacific Northern Gas Ltd. completed $15 million in financing. Additions to property, plant and equipment reached a total of $6 million in 2002. A new, seven-year contract with Methanex Corporation was successfully negotiated. Pacific Northern Gas Ltd. filed revenue requirements applications with the British Columbia Utilities Commission, seeking the Commission's approval of rates for 2003 and requesting approval of a new deferral account in all divisions. A settlement of the western system 2003 revenue requirements application was negotiated with its customers. The annual report presented a highlight of all activities, including corporate governance and management discussions and analysis. Consolidated financial statements were also provided. tabs

  16. Detailed radon emanation mapping in Northern Latium

    International Nuclear Information System (INIS)

    Detailed radon surveys over 5,000 km2 of Northern Latium, covering the northern part of the volcanic province of Central Italy, commenced in the mid eighties as part of a geothermal exploration programme; the surveys have subsequently been continued and amplified with environmental protection in mind. The area is now covered by ground emission maps, radon levels in water supplies, emissions from the different lithologies and concentrations in houses. The high uraniferous content of the volcanics, the porous nature of the ubiquitous pyroclastics, and active geothermal systems in the area combine to convey to ground level high concentrations of radon. The emissions show strong lateral variations which are geologically and tectonically controlled, such that only detailed surveys reveal the extent and locations of anomalous radon emanations. Unfortunately, long ago towns often developed in strategic locations. For Northern Latium this means on volcanic highs formed by faulted tuff blocks, two geological features associated with particularly high radon emissions. As a result, in contrast to the low average indoor radon concentrations for the greater part of Italy, in some of these town the average values exceed 450 Bq/m3. (author). 1 fig

  17. Obtención de inoculantes bacterianos y evaluación de su aplicación en procesos de biorremediación de suelos contaminados con hidrocarburos policíclicos aromáticos (PAH) de la Patagonia semiárida

    OpenAIRE

    Madueño, Laura

    2013-01-01

    El objetivo general del siguiente trabajo es contribuir al mejoramiento de los conocimientos básicos que permitan evaluar y mejorar las tecnologías de biorremediación. Los objetivos específicos son: • Aislar a partir de suelos de la Patagonia semiárida, microorganismos degradadores de PAH capaces de resistir condiciones ambientales de la región. • Evaluar la aplicabilidad de las estrategias ABA de bioaumento sobre la biorremediación de suelos patagónicos contaminados con PAH y con m...

  18. Evidencia morfológica e isoenzimática de hibridación natural entre Nothofagus antarctica y N. pumilio en el noroeste patagónico Morphological and isozyme evidence of natural hybridization between Nothofagus antarctica and N. pumilio in northwestern Patagonia

    OpenAIRE

    PAULA QUIROGA; ROMINA VIDAL RUSSELL; ANDREA C PREMOLI

    2005-01-01

    En este trabajo se estudió la hibridación entre Nothofagus pumilio y N. antarctica mediante análisis de morfología foliar y de electroforesis isoenzimática en la población de altura de Laguna Negra en el noroeste de la Patagonia, Argentina. Muestras colectadas en esta población para análisis morfológicos y genéticos fueron comparadas con poblaciones puras de N. antarctica y N. pumilio. Las especies puras resultaron estadísticamente diferentes entre sí para las variables morfológicas, y el aná...

  19. Neotectonics in the northern equatorial Brazilian margin

    Science.gov (United States)

    Rossetti, Dilce F.; Souza, Lena S. B.; Prado, Renato; Elis, Vagner R.

    2012-08-01

    An increasing volume of publications has addressed the role of tectonics in inland areas of northern Brazil during the Neogene and Quaternary, despite its location in a passive margin. Hence, northern South America plate in this time interval might have not been as passive as usually regarded. This proposal needs further support, particularly including field data. In this work, we applied an integrated approach to reveal tectonic structures in Miocene and late Quaternary strata in a coastal area of the Amazonas lowland. The investigation, undertaken in Marajó Island, mouth of the Amazonas River, consisted of shallow sub-surface geophysical data including vertical electric sounding and ground penetrating radar. These methods were combined with morphostructural analysis and sedimentological/stratigraphic data from shallow cores and a few outcrops. The results revealed two stratigraphic units, a lower one with Miocene age, and an upper one of Late Pleistocene-Holocene age. An abundance of faults and folds were recorded in the Miocene deposits and, to a minor extent, in overlying Late Pleistocene-Holocene strata. In addition to characterize these structures, we discuss their origin, considering three potential mechanisms: Andean tectonics, gravity tectonics related to sediment loading in the Amazon Fan, and rifting at the continental margin. Amongst these hypotheses, the most likely is that the faults and folds recorded in Marajó Island reflect tectonics associated with the history of continental rifting that gave rise to the South Atlantic Ocean. This study supports sediment deposition influenced by transpression and transtension associated with strike-slip divergence along the northern Equatorial Brazilian margin in the Miocene and Late Pleistocene-Holocene. This work records tectonic evidence only for the uppermost few ten of meters of this sedimentary succession. However, available geological data indicate a thickness of up to 6 km, which is remarkably thick for

  20. Accumulation of carbon in northern mire ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Tolonen, K.; Turunen, J.; Alm, J. [Joensuu Univ. (Finland). Dept. of Biology; Korhola, A. [Helsinki Univ. (Finland). Lab. of Physical Geography; Jungner, H. [Helsinki Univ. (Finland). Dating Lab.; Vasander, H. [Helsinki Univ. (Finland). Dept. of Forest Ecology

    1996-12-31

    The basic feature in the functional ecology of any mire ecosystem is retardation of the effective decay of organic material resulting in a conspicuous accumulation of plant debris as peat overtime. The carbon accumulation process is slow, and climatic change may have an impact on the carbon cycle of peatlands, therefore, it has been of interest to study the rate of carbon accumulation by geological methods from dated peat strata. The approach is hampered by several facts. First, the mires vary enormously as to their vegetation and hydrology and hence their production and decay properties. It follows that a great number of study sites are needed. Second, the peat in mires expands both vertically and laterally, and this requires a spatial reconstruction of carbon accumulation within a mire basin. Third, simple geological methods cannot account for the actual rate of carbon accumulation in peat, and finally, an additional carbon sink in the mire ecosystems can be the mineral subsoil beneath peat. The proposed warming will perhaps shift northwards the existing climatic mire regimes and, thus, the northern aapa fens will change to Sphagnum bogs that are more effective in sequestering carbon, but distinctly less effective in their CH{sub 4} and N{sub 2}O emanation. The role of mire fires in more remote northern areas may then become another important factor. The answer to the important question of future total sequestration of carbon to peatlands depends on the precipitation and its seasonal distribution pattern. Most climatic scenarios predict a decrease in the evaporation surplus during the summer at northern regions. Presumably, the consequent lowering of the water table would improve growth of forest on mires and simultaneously decrease the methane fluxes from peat. The combined net effect could be a clear restraining of the radiative forcing

  1. First archaeomagnetic data from northern Iberia

    Science.gov (United States)

    Ruiz-Martínez, V. C.; Pavón-Carrasco, F. J.; Catanzariti, G.

    An archaeomagnetic study has been conducted on eight archaeological structures (two kilns, four fireplaces and two saunas) from two different areas in Asturias (northern Spain). The results provide the first archaeomagnetic directions from the northern Iberian Peninsula. The main goal of this paper is to improve on the non-uniform site distribution used to construct the first archaeomagnetic Secular Variation Curve for Iberia (“SVC-I”) by studying new sites from northern Spain, an area currently not represented. The lithologies of some of the studied archaeological structures from this zone (slates, quartzites) differ from those of the rest of the peninsula. Laboratory analysis includes both thermal and alternating field stepwise demagnetization and rock-magnetic studies. A low coercivity, moderate unblocking temperature ( Tub) phase, such as magnetite/maghemite, seems to be the carrier of the archaeomagnetic signal. This sometimes overlaps partially with a (geological) high coercivity/high Tub phase. Site-mean characteristic directions have been calculated following a hierarchical approach and applying Fisherian distribution tests. Archaeomagnetic results have been compared, applying Fisherian distribution tests, among themselves and with Roman age entries of the Spanish archaeomagnetic database. They have also been compared with the reference “SVC-I” using Bayesian methods. These analyses have served to validate the archaeological dating of the structures. There is a good agreement between the results of archaeomagnetic dating and radiocarbon dating, both of which are consistent with archaeological constraints. The uncertainties in the archaeomagnetic ages are relatively large mainly because the reference curve hardly varies in declination during Roman times. This highlights the need of more high quality archaeomagnetic data (from very well-dated structures) in order to reduce the errors associated with the reference “SVC-I” and the archaeomagnetic

  2. Northern Eurasian Heat Waves and Droughts

    Science.gov (United States)

    Schubert, Siegfried; Wang, Hailan; Koster, Randal; Suarez, Max; Groisman, Pavel

    2013-01-01

    This article reviews our understanding of the characteristics and causes of northern Eurasian summertime heat waves and droughts. Additional insights into the nature of temperature and precipitation variability in Eurasia on monthly to decadal time scales and into the causes and predictability of the most extreme events are gained from the latest generation of reanalyses and from supplemental simulations with the NASA GEOS-5 AGCM. Key new results are: 1) the identification of the important role of summertime stationary Rossby waves in the development of the leading patterns of monthly Eurasian surface temperature and precipitation variability (including the development of extreme events such as the 2010 Russian heat wave), 2) an assessment of the mean temperature and precipitation changes that have occurred over northern Eurasia in the last three decades and their connections to decadal variability and global trends in SST, and 3) the quantification (via a case study) of the predictability of the most extreme simulated heat wave/drought events, with some focus on the role of soil moisture in the development and maintenance of such events. A literature survey indicates a general consensus that the future holds an enhanced probability of heat waves across northern Eurasia, while there is less agreement regarding future drought, reflecting a greater uncertainty in soil moisture and precipitation projections. Substantial uncertainties remain in our understanding of heat waves and drought, including the nature of the interactions between the short-term atmospheric variability associated with such extremes and the longer-term variability and trends associated with soil moisture feedbacks, SST anomalies, and an overall warming world.

  3. Principles for poverty alleviation among the youth in Northern Uganda

    Directory of Open Access Journals (Sweden)

    A. Wilson

    2010-07-01

    Full Text Available This article deals with the statistical data and analysis con-cerning poverty among the young people in Uganda. The poverty is continuously ascending, with the most affected region being Northern Uganda. The major cause of poverty in Uganda has been the “South-North divide” fuelled by poor political leadership, that divides people along the lines of politics and ethnicity. Poverty has caused many young people of Northern Uganda to resort to rebellion against the government currently in power. This has led to unending political instability and civil strife most especially in Northern Uganda. In this article atten-tion is given to the conflict in Northern Uganda and attempts are made to propose some amicable resolutions. The discussion includes the current poverty scenario in Northern Uganda and possible strategies for reducing the poverty rate that has caused much damage in Northern Uganda.

  4. 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.

  5. Cambios en lagos y circulación fluvial vinculados al calentamiento climático del Pleistoceno tardío-Holoceno temprano en Patagonia e isla 25 de mayo, islas Shetland del Sur, Antártida

    Directory of Open Access Journals (Sweden)

    R.A. del Valle

    2007-12-01

    Full Text Available El calentamiento clim ático que afectó a la Patagonia en el Pleistoceno tardío-Holoceno temprano produjo cambios en la morfología del paisaje, incluyendo la génesis, desarrollo y desintegración de grandes lagos al este de los Andes. Hasta entonces, los glaciares y sus morenas formaban diques naturales que embalsaron las aguas de deshielo y mantenían alto el nivel de las aguas en los grandes paleolagos. Posteriormente, la migración hacia el sur de la mejoría climática ocasionó la progresiva fusión del campo de hielo regional, y las morenas fueron cortadas por la erosión fluvial, cuando el calentamiento climático impactó plenamente en la región. El proceso afectó a la región de norte a sur en tiempos diferentes: 1 hace c. 13.200 años en el norte, 2 durante la transición Pleistoceno/Holoceno en la parte central, y 3 finalmente, en Tierra del Fuego hace unos 7.800 años. El rápido retroceso de los glaciares produjo el desalojo de los valles andinos a ambos lados de la cordillera, lo cual abrió cauces fluviales que atraviesan la cordillera desde entonces, inaugurando el drenaje hacia el océano Pacífico de grandes lagos glaciales que existían al oriente de los Andes. Esto resultó en el rápido descenso del nivel de los paleolagos. Un proceso similar ocurrió en las islas Shetland del Sur (Antártida hace unos 6.000 años.

  6. Freshwater reservoir effect variability in Northern Germany

    DEFF Research Database (Denmark)

    Philippsen, B.; Heinemeier, J.

    2013-01-01

    The freshwater reservoir effect is a potential problem when radiocarbon dating fish bones, shells, human bones, or food crusts on pottery from sites near rivers or lakes. The reservoir age in hardwater rivers can be up to several thousand years and may be highly variable. Accurate 14C dating of f...... that can also be expected for the past. This knowledge will be applied to the dating of food crusts on pottery from the Mesolithic sites Kayhude at the Alster River and Schlamersdorf at the Trave River, both in Schleswig-Holstein, northern Germany....

  7. Northern Jutland as an Intertextual Location

    DEFF Research Database (Denmark)

    Hansen, Kim Toft; Christensen, Jørgen Riber

    Rushmore's presidential sculptures from Hitchcock's North by Northwest (1959). More generally, places may also appear as stereotypical location topoi. E.g., underground car parks are recognized from innumerable crime films and thrillers as a dramaturgically perilous location, and not just as an Augé...... Northern Jutland can be regarded as a location potential of this kind, which is can promote film and media production in the region. An important point in this connection will be that there may be a local and peripheral wish to become an intertextual location because this may lead to regional development...

  8. The 2011 Northern Hemisphere Solar Maximum

    Science.gov (United States)

    Altrock, Richard C.

    2013-01-01

    Altrock (1997, Solar Phys. 170, 411) discusses a process in which Fe XIV 530.3 nm emission features appear at high latitudes and gradually migrate towards the equator, merging with the sunspot "butterfly diagram". In cycles 21 - 23 solar maximum occurred when the number of Fe XIV emission regions per day > 0.19 (averaged over 365 days and both hemispheres) first reached latitudes 18°, 21° and 21°, for an average of 20° ± 1.7°. Another high-latitude process is the "Rush to the Poles" of polar crown prominences and their associated coronal emission, including Fe XIV. The Rush is a harbinger of solar maximum (cf. Altrock, 2003, Solar Phys. 216, 343). Solar maximum in cycles 21 - 23 occurred when the center line of the Rush reached a critical latitude. These latitudes were 76°, 74° and 78°, respectively, for an average of 76° ± 2°. Cycle 24 displays an intermittent Rush that is only well-defined in the northern hemisphere. In 2009 an initial slope of 4.6°/yr was found in the north, compared to an average of 9.4 ± 1.7 °/yr in the previous three cycles. However, in 2010 the slope increased to 7.5°/yr. Extending that rate to 76° ± 2° indicates that the solar maximum smoothed sunspot number in the northern hemisphere already occurred at 2011.6 ± 0.3. In the southern hemisphere the Rush is very poorly defined. A linear fit to several maxima would reach 76° in the south at 2014.2. In 1999, persistent Fe XIV coronal emission connected with the ESC appeared near 70° in the north and began migrating towards the equator at a rate 40% slower than the previous two solar cycles. A fit to the early ESC would not reach 20° until 2019.8. However, in 2009 and 2010 an acceleration occurred. Currently the greatest number of emission regions is at 21° in the north and 24°in the south. This indicates that solar maximum is occurring now in the north but not yet in the south. The latest global smoothed sunspot numbers show an inflection point in late 2011, which

  9. Offshore wind market outlook in Northern Europe

    Energy Technology Data Exchange (ETDEWEB)

    Pimenta de Miranda, Wilfried; Trulsson, Ola; Ekloef, Eva-Britt; Niemenen, Karel

    2010-08-15

    After more than 10 years of slow developments, the offshore wind market is now accelerating. Thanks to a sustained political drive from UK and Germany, the rest of Northern Europe is now following the path as offshore wind is being recognized as one of the key resources available to the EU to meet its renewable energy ambitions. Exposed to increasing technical issues, rising costs and the financial crisis, lessons learned are now being shared and integrated throughout Europe and appropriate regulatory and planning reforms are now being deployed to speed the deployment of offshore wind. (Author)

  10. Multiculturalism and sectarianism in post-agreement Northern Ireland

    OpenAIRE

    Geoghegan, Peter

    2008-01-01

    This dissertation contributes to existing scholarship on contemporary multiculturalism. It does so by exploring how multicultural agendas are operationalised in Northern Ireland – a society divided along sectarian lines. As the political violence of the conflict has receded, Northern Ireland has witnessed unprecedented levels of in-migration. This dissertation seeks to understand how, as Northern Irish society is increasingly being conceived of as culturally diverse, emergin...

  11. 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

    Directory of Open Access Journals (Sweden)

    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.

  12. Sonoma Ecology Center Northern California Arundo Distribution Data

    Data.gov (United States)

    California Department of Resources — The Arundo Distribution layer is a compilation of Arundo donax observations in northern and central California, obtained from numerous sources, including Arundo...

  13. Study on the Economic Differences between Northern and Southern Xinjiang

    Institute of Scientific and Technical Information of China (English)

    Juncheng; DONG

    2014-01-01

    There are great regional economic differences between northern and southern Xinjiang and the expansion of regional economic differences jeopardize social development and social stability,resulting in more serious polarization between the rich and the poor in northern and southern Xinjiang,thereby hampering further improvement of the economic efficiency in Xinjiang. Using factor analysis,this article carries out comprehensive analysis of regional economic differences in Xinjiang,derives the reasons for regional economic differences between northern and southern Xinjiang,and proposes recommendations for narrowing the regional economic differences between northern and southern Xinjiang.

  14. From the Northern Eurasia Earth Science Partnership Initiative (NEESPI) towards the Northern Eurasia Future Initiative (NEFI)

    Science.gov (United States)

    Groisman, Pavel; Gutman, Garik; Gulev, Sergey; Maksyutov, Shamil

    2015-04-01

    Northern Eurasia Earth Science Partnership Initiative (NEESPI, http://neespi.org) was launched in 2004. With its multidisciplinary focus, the internationally funded NEESPI (more than 170 individual international projects during the past decade) has challenged participants to research climate-ecosystem interactions, societal impacts from extreme events in Northern Eurasia, and the feedbacks of these interactions and impacts to the global Earth system. NEESPI was endorsed by major ESSP Programs and Projects and the cornerstone support for the NEESPI studies was provided by the NASA Land Cover and Land Use Change Program and the Russian Academy of Sciences. Now it is the time to synthesis the main achievements of the NEESPI researchers and to re-assess its Science Questions and Objectives of the regional research within the new Future Earth Program paradigm with the focus on interdisciplinary solution-oriented approach that will allow effective policy-making in environment management and control. At the sequence of Workshops (the last of them will be in Prague one week prior to this Assembly) we formulated a major Science Question of the new Northern Eurasia Future Initiative (NEFI): "What will the changes in the regional ecosystems dynamics and interactions mean for the societal well-being, activities, health, and strategic planning in Northern Eurasia?" The major NEFI challenge will be the services aimed on providing in Northern Eurasia a sustainable societal development in changing climate, ecosystems, and societies. At this presentation we shall brief the audience about the main results of the NEESPI researchers, and lay down the plans for the future NEFI studies. At the side event of the Meeting, we shall initiate preparation of the book which will synthesize major NEESPI achievements.

  15. Proposed artificial recharge studies in northern Qatar

    Science.gov (United States)

    Kimrey, J.O.

    1985-01-01

    The aquifer system in northern Qatar comprises a water-table aquifer in the Rus Formation which is separated by an aquitard from a partially confined aquifer in the top of the overlying Umm er Radhuma Formation. These two aquifers are composed of limestone and dolomite of Eocene and Paleocene age and contain a fragile lens of freshwater which is heavily exploited as a source of water for agricultural irrigation. Net withdrawals are greatly in excess of total recharge, and quality of ground water is declining. Use of desalinated seawater for artificial recharge has been proposed for the area. Artificial recharge, on a large scale, could stabilize the decline in ground-water quality while allowing increased withdrawals for irrigation. The proposal appears technically feasible. Recharge should be by injection to the Umm er Radhuma aquifer whose average transmissivity is about 2,000 meters squared per day (as compared to an average of about 200 meters squared per day for the Rus aquifer). Implementation of artificial recharge should be preceded by a hydrogeologic appraisal. These studies should include test drilling, conventional aquifer tests, and recharge-recovery tests at four sites in northern Qatar. (USGS)

  16. Fences and grazing management in northern Namibia

    Science.gov (United States)

    Prudat, Brice; Bloemertz, Lena; Kuhn, Nikolaus J.

    2016-04-01

    Since Namibian independence, many fences have been erected in the communal land of the Ohangwena region in northern Namibia. Most fencing issues discussed so far in the region concern large-scale fencing of communal land by the new Namibian elite. Rarely discussed are the fences erected around small-scale farmers' parcels. This paper will discuss the impact of such increased small-scale fencing activities in northern Namibia. Fencing of land has different functions, including protection of fields against livestock and securing property rights. However, not all community members can afford the monetary and labor costs involved. In the annual agricultural cycle of the study area, livestock is left un-herded after the harvest of most crops. They can then feed on available crop remains and grass on the fields. The livestock then freely utilizes unfenced and unprotected land. This system has the advantage to accelerate crop degradation and fertilize the soils. However, by erecting efficient fences, the new middle-class community members concentrate fertility in their own field, thereby degrading agricultural soils of poorer farmers. Potentially, such small-scale fencing of land has therefore an impact on sol quality and thus fosters degradation of unfenced cropland. By using fences as features to determine the limits of the new land rights, the ongoing Communal Land Reform may not only promote the erection of fences, but may also have a negative impact on soil quality and potentially food security of small-scale farmers without cattle.

  17. Rainfall variability and seasonality in northern Bangladesh

    Science.gov (United States)

    Bari, Sheikh Hefzul; Hussain, Md. Manjurul; Husna, Noor-E.-Ashmaul

    2016-05-01

    This paper aimed at the analysis of rainfall seasonality and variability for the northern part of South-Asian country, Bangladesh. The coefficient of variability was used to determine the variability of rainfall. While rainfall seasonality index (SI ) and mean individual seasonality index ( overline{SI_i} ) were used to identify seasonal contrast. We also applied Mann-Kendall trend test and sequential Mann-Kendall test to determine the trend in seasonality. The lowest variability was found for monsoon among the four seasons whereas winter has the highest variability. Observed variability has a decreasing tendency from the northwest region towards the northeast region. The mean individual seasonality index (0.815378 to 0.977228) indicates that rainfall in Bangladesh is "markedly seasonal with a long dry season." It was found that the length of the dry period is lower at the northeastern part of northern Bangladesh. Trend analysis results show no significant change in the seasonality of rainfall in this region. Regression analysis of overline{SI_i} and SI, and longitude and mean individual seasonality index show a significant linear correlation for this area.

  18. Floods in Canada and Northern Minnesota

    Science.gov (United States)

    2002-01-01

    During the first half of June, heavy rains inundated northern Minnesota and southern Canada, giving rise to floods that drove hundreds of people from their homes and drenched more than 300,000 acres of prime farmland. This false-color image of the flood (right) was acquired on June 15, 2002, by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. The worst of the flooding occurred on the border of Canada and Minnesota along the Roseau River, which now resembles a lake in the center of the image. The town of Roseau, Minnesota, which sits in the eastern end of the newly formed lake, was hit the hardest. Nearly all the buildings in the town took heavy water damage and many residents were forced to leave. Widespread flooding across an eight county region in Minnesota has drenched nearly 300,000 to 500,000 acres of farmland altogether. Many of the farmers hit lost 100 percent of their crops and will be unable to plant again for the season. Last week, President Bush declared northern Minnesota a disaster area. Normally, the Roseau River cannot even be seen on a MODIS image (left, acquired May 21, 2002), and the surrounding area is dry. In the false-color images, sage green, rusty orange, and blue is land, and water is black. Clouds are white and pink. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  19. Airborne radioiodine in northern Serbia from Fukushima

    International Nuclear Information System (INIS)

    The results obtained with the monitoring system set up to assess the impact of the Fukushima accident on the environment of Vojvodina (Northern Province of Serbia) are presented and discussed. Aerosol, rain, fresh milk and spinach samples were collected daily in the weeks following the accident. In the aerosol samples, 131I activity concentrations of several mBq m−3 were measured, while in rain, milk and spinach samples, 131I levels had values in a range of (0.3–1.7) Bq kg−1. These are the first results on the impact of the Fukushima accident on the Pannonian basin region. Our results are compared with the reported values from other parts of the world. - Highlights: ► I-131 from the Fukushima power plant was detected in the northern part of Serbia. ► In the aerosol samples the activity concentration of 131I has been measured to be of mBq m−3 order of magnitude. ► The concentrations of 131I in the rain, milk and spinach samples were in the range of (0.3–1.7) Bq kg−1. ► The time distributions of airborne I-131 during March–April of 2011 in the USA, Germany, Serbia and Greece are compared.

  20. Northern New Mexico regional airport market feasibility

    Energy Technology Data Exchange (ETDEWEB)

    Drake, R.H.; Williams, D.S.

    1998-06-01

    This report is about the market for airline travel in northern New Mexico. Interest in developing a northern New Mexico regional airport has periodically surfaced for a number of years. The New Mexico State Legislature passed a memorial during the 1998 Second Session calling for the conduct of a study to determine the feasibility of building a new regional airport in NNM. This report is a study of the passenger market feasibility of such an airport. In addition to commercial passenger market feasibility, there are other feasibility issues dealing with siting, environmental impact, noise, economic impact, intermodal transportation integration, region-wide transportation services, airport engineering requirements, and others. These other feasibility issues are not analyzed in any depth in this report although none were discovered to be show-stoppers as a by-product of the authors doing research on the passenger market itself. Preceding the need for a detailed study of these other issues is the determination of the basic market need for an airport with regular commercial airline service in the first place. This report is restricted to an in-depth look at the market for commercial passenger air service in NNM. 20 figs., 8 tabs.