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.
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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. Situated at the southern margin of the hemispheric westerly wind belt and immediately north of the Antarctic Polar Frontal zone, Tierra del Fuego is well-positioned to monitor coupled changes in the ocean-atmosphere system of the high southern latitudes.
We use an AMS radiocarbon chronology for the last 8, years based on pollen concentrates, thereby avoiding contamination from bedrock-derived lignite. Our chronology is consistent with a tephrochronologic age date for deposits from the middle Holocene Volcan Hudson eruption. We attribute this variability to westerly wind-derived precipitation. Increased wind strength and precipitation in the late Holocene drives the Nothofagus forest eastward and enhances run-off and terrigenous inputs to the lake.
Species richness and faunistic affinities of the Gammaridea and Corophiidea Amphipoda from shallow waters of southern Tierra del Fuego , Argentina: preliminary results. Directory of Open Access Journals Sweden. Full Text Available Species richness and faunistic affinities of gammaridean and corophiidean amphipods from southern Tierra del Fuego were studied.
The material was collected with dredges and grabs at 7 locations 15 sampling stations in a range of 5 to 35 m depth. A total of 61 species belonging to 20 families and 43 genera were identified. The genera Cephalophoxoides, Ceradocopsis and Photis are reported for the first time from the Magellan region and 3 species belonging to Atylus, Ischyrocerus and Photis appear to be new to science.
Most of the species collected belong to Phoxocephalidae, whereas most individuals were contained in the Stenothoidae and Lysianassidae s. In addition, 6 species extend beyond the Magellan region as far as Oceania. Full Text Available Stomach contents of false southern king crabs Paralomis granulosa, between 10 to 90 mm CL from the Beagle Channel Golondrina Bay and Roca Mora, Argentina, were examined by the frequency of occurrence method of analysis and by a food index.
Roca Mora is an area where juveniles 60 mm CL are common; in this last area sexual segregation was also observed. The principal food groups for crabs of Golondrina Bay were algae, molluscs, crustaceans, bryozoans and foraminiferans; for crabs from Roca Mora the natural diet consisted of three major food groups: hydrozoans, echinoderms and foraminiferans.
The relative frequency of different prey groups varied in relation to the size, season and sex. There were no significant differences in the quantity of food consumed by sexes in both areas.
Generally small crabs 50 mm CL. Juveniles consumed a greater amount of food during winter and spring. In summer moulting period, juveniles had the highest vacuity index. Adults consumed minor amounts of food during autumn, before the spawning-moulting-mating period when the vacuity index was higher spring.
Full Text Available The following paper presents a project of Cultural Routes designed for the Chilean Tierra del Fuego , linked to promoting tourism and boosting the economy, through the development of a specific high standard tourism offer, linked to its natural and cultural heritage, with the purpose of capturing the potential income generation for Chile. The project had as main goal to enhance the competitiveness of the tourism sector of special interests in Tierra del Fuego , a key sector of Southern Patagonia, through the dissemination and transfer of technologies and knowledge, acquired in over 10 years of research and projects, onto the territory and local agents.
These Cultural Routes build an innovative offer, capable of structuring the diverse touristic resources and strengthening the basis for the development of a new stage of national and international tourism market, located on the southern extreme of Chile and America.
Contiene mapas con las principales expediciones argentinas. A narration of the leading maritime and terrestrial expeditions in Fuegia during the XIX and XX centuries is approached from the point of view of the mycological exploration and published results on the mycobiota, emphazising the Argentine expeditions.
Maps with the itinerary of main Argentine expeditions is given. An evaluation of the fungal diversity according to the previous review is presented, comparing the fungal records during both periods that shows duplication of the total number of taxa from species described in XIX century to in the XX century.
Simultaneously there is a decrease from A list of collectors and a table with the state of ex-situ conservation of selected species is presented. A brief comment is given on conservation of habitats supporting fungal population that are disturbed by unsustainable exploitation of natural resources.
A pesar de que dichos acabados se han utilizado profusamente e Full Text Available There were thinkers who foretold in their time the signs of the coming catastrophe. They were not prophets but fine analysts. We are referring to Rosenzweig, Benjamin and Kafka. In the "idealism" of the philosophy that comes from Jonia and reaches Jena, Rosenzweig animadverted on the tendency to a totalitarianism that potentially converted it into an "ontology of war".
Benjamin brought to light the radical ambiguity within the concept of progress, so fundamental to the illustrated thought. Barbarism, in general, and fascism, in particular, are not the opposite to progress but one of its possibilities. That fatal possibility is, for the victim, the rule. Kafka traced with foresight the fascist reduction of man to bare life in the recurrent animalisation of his characters, as well as the denial of the other in those presented as victims of incommunications.
No eran profetas sino finos analistas. Nos referimos a Rosenzweig, Benjamin y Kafka. La barbarie, en general, y el fascismo, en particular, no son lo opuesto al progreso sino una de sus posibilidades.
Full Text Available Telmatococcus igniumterrae gen. The new monotypic genus differs from all known genera of Eriococcidae in having short cylindrical truncated setae of the anal apparatus and pouches with numerous quinquelocular pores near the anal apparatus. The habitat of the new taxon is characterized. Cultural tourism in fragile institutional contexts: project for cultural routes in Tierra del Fuego.
The following paper presents a project of Cultural Routes designed for the Chilean Tierra del Fuego , linked to promoting tourism and boosting the economy, through the development of a specific high standard tourism offer, linked to its natural and cultural heritage, with the purpose of capturing the potential income generation for Chile.
The project had as main goal to enhance the competitiveness of the tourism sector of special interests in Tierra del Fuego , a key sector of South Full Text Available Corallinales Rhodophyta in Tierra del Fuego are abundant, with 9 genera, 17 species and 1 subspecies. Pseudolithophyllum with 1 species P. The genera Parahydrolithon with 4 species P.
Clathromorphum with 4 species Cl. Variabile and a share of 5. The remaining three genera, Bossiella with 1 subspecies B. The characteristic vertical distribution of the species in the intertidal and subtidal zone of Tierra del Fuego is given. The Corallinales in the Antarctic Region are poorly known and need further investigation. Together these things form a constitutive part the territorial identity of southern Patagonia.
The cartography, the scientific expeditions, the religious missions, the journalism and the literature played an important role in the diffusion and permanency of these representations.
In modern Western societies, companies have positioned the concept as a powerful tourist resource, capable of motivating travelers coming to Tierra del Fuego. In the perceived images of Tierra del Fuego , there is an intermingling of the archaic, the legend and the distance, the impregnable vastness of the nature and the recollection of heroic expeditions.
The architecture of the extremes cultural landscapes in Tierra del Fuego. This is the case of Tierra del Fuego , con Se discuten las implicaciones de esta evidencia para las pautas conductuales de cazadores-recolectores en la costa sur de Tierra del Fuego.
This site is located in a coastal setting in the middle section of the Moat River Basin and records occupations during the Late Holocene ca.
Technological diversity and the zooarchaeological record point to the development of multiple activities. Lithic artifacts dominate the technological assemblage.
Lithic debitage indicates a strong emphasis towards final stages of reduction, shown by the lower occurrence of artifacts with cortex and the high frequency resharpening. Two short cores cm were sampled using a Livingstone piston corer during the southern fall.
Sediments are massive green clays to 70 cm depth with irregularly spaced thin sandy strata and lens. Massive yellow clay with thin sandy strata continues up to 30 cm depth; from here up to 10 cm yellow massive clays domain.
The topmost 10 cm are mixed yellow and green clays with fine sand. Additionally, we present results of magnetic parameters measured with vibrating sample magnetometer VSM. The stability of the NRM was analyzed by alternating field demagnetization. The magnetic properties have shown variable values, showing changes in both grain size and concentration of magnetic minerals.
It was found that the main carrier of remanence is magnetite with the presence of hematite in very low percentages. This is the first paleomagnetic study performed in lakes located in the northern, semiarid fuegian steppe, where humid-dry cycles have been interpreted all along the Holocene from an aeolian paleosoil sequence Orgeira et el, Comparison between paleomagnetic records of Laguna Carmen and results obtained in earlier studies carried out at Laguna Potrok Aike Gogorza et al.
Se discute la importancia del registro y se entregan ilustraciones del ejemplar. Identifying potential differences in ontogentic ages between modern and archaeological Nacella deaurata shells, Tierra del Fuego , Argentina. Patelloid limpet shells are common constituents of rocky shore habitats along the eastern Atlantic basin and are often found in archaeological shell middens.
Nacella deaurata is an intertidal species found in the Magellanic Province along the southern tip of South America. Recent discoveries of archaeological shell middens in Tierra del Fuego , Argentina, identify N.
Preliminary observations reveal that modern N. Here, we provide preliminary data to test the hypothesis that the larger, modern specimens grow to older ontogenetic ages than the smaller archaeological specimens.
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