1,721,014 research outputs found
Ecología e historia natural de la Patagonia Andina : un cuarto de siglo de investigación en biogeografía, ecología y conservación
No full textVisto desde el espacio, el extremo sur del continente americano aparece como una región primordialmente amarronada. Es la extensa y semiárida estepa Patagónica, un bioma dominado por pastos y arbustos bajos, que ocupa la mayor parte de esta región y que se extiende desde el Océano Atlántico hasta los primeros contrafuertes de los Andes australes. Sin embargo, si se mira con más detalle también se puede observar una estrecha franja verde, de 100 a 250 km
de ancho, a lo largo de la costa del Océano Pacífico. Es el bosque andino patagónico que se extiende por más de 2500 km entre los 35o y 55o de latitud S, en el sur de la isla de Tierra de Fuego, donde termina el continente. Compartido por Argentina y Chile, este es un bioma único en términos de su
biodiversidad y de los procesos que le han dado lugar.Fil: Raffaele, Estela. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina.Fil: Raffaele, Estela. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina.Fil: Raffaele, Estela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: de Torres Curth, Mónica. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina.Fil: Morales, Carolina L. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina.Fil: Morales, Carolina L. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Kitzberger, Thomas. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina.Fil: Kitzberger, Thomas. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina.Fil: Kitzberger, Thomas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Manejo de Bosque con Ganadería Integrada (MBGI).
Full text linkEl Ministerio de Agricultura, Ganadería y Pesca, en conjunto con la Secretaría de Ambiente y Desarrollo Sustentable, firmaron en 2015 un acuerdo general sobre principios y lineamientos nacionales para el manejo de bosques con ganadería integrada, en concordancia con la Ley de Bosque Nativo (26.331). Dicho acuerdo plantea que es posible compatibilizar la producción ganadera con la preservación del bosque. Si consideramos al bosque como un sistema complejo donde la funcionalidad está dada por múltiples procesos, y donde habitan e interactúan diferentes organismos desde el suelo hasta el dosel arbóreo.EEA Santa CruzFil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Peri, Pablo Luis. Universidad Nacional de la Patagonia Austral; Argentina.Fil: Peri, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Raffaele, Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente (INBIOMA); Argentina. Universidad Nacional del Comahue; ArgentinaFil: Raffaele, Estela. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina
Predator feeding ecology on Patagonian rocky outcrops: implications for colonies of mountain vizcacha (Lagidium viscacia)
No full textABSTRACT: On 10 rocky outcrops with mountain vizcacha colonies, diets and trophic relations of five predator species were analyzed to evaluate their impact in vizcacha populations. Diets included 17 prey items of which mammals represented 97% of biomass. Lagomorphs were the most important prey, followed by sigmodontines, tuco-tucos, and mountain vizcachas. The Barn Owl was a specialized predator, while the culpeo and lesser grison were generalized consumers. Predation of mountain vizcacha by Magellanic Horned Owls and culpeo foxes could increase vizcacha vulnerability because vizcacha populations are small and fragmented, and females produce only one offspring per year.Fil: Galende, Gladys I.. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Departamento de Zoología; ArgentinaFil: Raffaele, Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin
Flammability of Patagonian invaders and natives: When exotic plant species affect live fine fuel ignitability in wildland-urban interfaces
No full textThe increasing influx of people moving to woodland environments in order to access social and natural amenities is generating conflicts which are becoming ever more intense and complex. Urban-forest interface issues are currently among the most serious and problematic issues for forest managers. The wildland-urban interface has grown in size in Patagonia because of an increase in area of human settlements intermingled with natural vegetation, giving rise to a disturbing new landscape dynamic associated with wildfires. Through laboratory tests we produced the first flammability plant list for northwest Patagonia, which includes exotic species that can frequently be found in wildland-urban interface areas. We identified groups of species according to live fine fuel characteristics and detected different types of flammability, based on ignitability and heat release. Our plant list allows comparison of native and exotic species, and the formulation of precautionary action to minimize environmental and economic risks.Fil: Blackhall, Melisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; ArgentinaFil: Raffaele, Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; Argentin
Summer behavior and diurnal activity of mountain vizcachas (Lagidium viscacia) in two colonies of Northwestern Patagonia
No full textThe mountain vizcacha (Lagidium viscacia) is a specialist of rocky habitats with colonies distributed along elevation gradients. Knowledge about its behavior is scarce and populations in northern Patagonia are declining. This is the first study describing the behavior and summer diurnal activity of two mountain vizcacha colonies under natural conditions. We registered by scan sampling the activities of 15 individuals during the period of 5 days. Vizcachas performed typical behaviors of rock specialists and allocated most of their time to foraging near the rock shelter (34%) and resting (26%). Behaviors such as locomotion (16%) and social interactions (10%) were important. Allogrooming (4.5%), vigilance (3%), and dust-bathing (1%) occupied a relatively small percentage of activities. In summer, the diurnal activity presented a bimodal distribution and was inversely related to the mean daytime air temperature, with a maximum peak between 8:00 and 9:00 h. Main activities such as foraging, resting, and locomotion were concentrated in the morning and at sunset. The behavioral responses suggest that the activity of this rodent in summer is influenced by thermal conditions. These results are a first important step in order to understand future vizcacha responses to climate change.Fil: Galende, Gladys Ines. Universidad Nacional del Comahue; ArgentinaFil: Raffaele, Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin
Cattle change plant reproductive phenology, promoting community changes in a post-fire Nothofagus forest in northern Patagonia, Argentina
Full text linkAims Variations in rates and length of flowering and fruiting not only affect the reproduction of a given plant species but also the behavior and reproduction of associated taxa. Flowering and fruiting variations may be influenced by herbivory, especially by large mammals. The aim of this study was to determine the effects of cattle browsing on the reproductive phenology of understory species in a subalpine post-fire Nothofagus forest in Patagonia.
Methods The effects of herbivory on plant reproductive phenology were studied in a set of experimental exclosures (fenced plots) installed since 2001 in a post-fire N. pumilio forest, located in Nahuel Huapi National Park (NHNP), Argentina. We monitored the beginning and duration of each reproductive phenological stage: floral bud, open flower, immature fruit and mature fruit. We also counted the number of flowers, fruits, seeds and viable seeds of the dominant plants to assess whether browsing modifies temporal patterns of the flowering and fruiting periods.
Important Findings Cattle reduced the total number of species flowering and fruiting and changed the reproductive phenology of some species. We found that palatable species seem to be negatively affected by browsing in terms of reduced fitness due to changes in flowering and fruiting periods. In contrast, cattle benefitted the reproduction of non-palatable species and could promote the invasion of shade-intolerant exotic forbs such as Cirsium vulgare. The effects of livestock reported in this study are important to understanding how browsing could alter native species establishment and possibly alter successional trajectories during recolonization after fire.Fil: de Paz, Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; ArgentinaFil: Raffaele, Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación en Biodiversidad y Medioambiente; Argentin
Mantillo de las especies leñosas de matorrales del NO de la Patagonia: abundancia, composición, estructura y heterogeneidad
Full text linkEl mantillo es un componente importante de los ecosistemas, que afecta tanto la dinámica de nutrientes como las condiciones de micrositio (e.g., radiación, temperatura y retención de humedad del suelo) y, en consecuencia, puede tener diferentes tipos de efectos sobre la regeneración de las especies. El objetivo de este trabajo fue estudiar, bajo el dosel de 15 especies leñosas, muy frecuentes en los matorrales del NO de la Patagonia, la abundancia, composición, estructura y heterogeneidad del mantillo y la producción de material senescente/año. El mantillo total acumulado varió entre 347,9 y 2534,7 gm-2. El mantillo y la producción de material senescente/año fue baja comparada con otros ecosistemas y similar a la del monte Patagónico. La heterogeneidad del mantillo fue similar entre la mayoría de las especies. Las especies perennifolias tuvieron mayor acumulación de mantillo y producción de material senescente por año que las especies caducifolias. Esto podría tener implicancias en la regeneración y ciclado de nutrientes a escala de comunidad. En ambos grupos funcionales se encontraron especies con valores extremos y otras que representan un gradiente de variación. Esto contribuye a darle a este sistema una alta diversidad de micrositios asociada al mantillo.Fil: Gobbi, M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; ArgentinaFil: Raffaele, Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; ArgentinaFil: de Paz, Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; Argentin
Birds as mediators of passive restoration during early post-fire recovery
Full text linkRemnant trees or artificial perches in burned areas can favor passive restoration through the perch effect. Birds consuming fruits in remnant vegetation patches or unburned adjacent communities are expected to defecate or regurgitate seeds as they perch on standing burned trees and shrubs in post-fire areas. The purpose of this study was to determine whether standing burned trees and shrubs are used by frugivorous birds as perching structures and if their maintenance promotes passive restoration of burned ecosystems. We: (a) recorded the seed rain of woody species in microsites underneath perches and in the open, (b) recorded seedling survival underneath the canopy of resprouting individuals and in the open, and (c) quantified seed rain and seedling recruitment of endozoochorous species at hectare level. Standing burned trees and shrubs were used as natural perches by frugivorous birds and increased seed arrival into recently burned communities. In addition, seedling survival was greater below the canopy of resprouting woody vegetation than in the open. Thus, standing burned trees and shrubs provide an important structural component attracting frugivorous birds, and therefore seeds during early post-fire regeneration. Resprouting trees and shrubs were also critical during post-fire recovery, because they act as seed traps, facilitate seedling survival and produce fruits that attract frugivorous birds, promoting seed flow among different communities at a landscape level. Therefore, the maintenance of standing burned woody vegetation could favor passive restoration of burned areas.Fil: Cavallero, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación en Biodiversidad y Medioambiente; ArgentinaFil: Raffaele, Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación en Biodiversidad y Medioambiente; ArgentinaFil: Aizen, Marcelo Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación en Biodiversidad y Medioambiente; Argentin
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
- …
