1,720,991 research outputs found
Plantaciones en Patagonia
Full text linkSe presenta un contrapunto sobre diferentes aspectos relacionados con las forestaciones en los ecosistemas del norte de la patagonia. Se aborda los principales efectos ambientales que ocasionan las forestaciones, las politicas de subsidios a las plantaciones y los efectos socialkes y economicos que pueden tener las plantacionesFil: Grosfeld, Javier Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; ArgentinaFil: Loguercio, Gabriel Angel. Universidad Nacional de la Patagonia; Argentin
Regeneration of Nothofagus dombeyi (Mirb.) Ørst. in little to moderately disturbed southern beech forests in the Andes of Patagonia (Argentina)
Full text linkNatural forests and stands subjected to little to moderate human impact are continuously declining worldwide and with these, their biodiversity and ecosystem services. Many Nothofagus forests in the south of the South American continent are in a pristine state or only moderately impacted by humans. Forest grazing by livestock, in the past and still today often practiced in a non-sustainable way is, however, increasingly under discussion to meet current environmental and socio-economic challenges. Accordingly, we investigate the regeneration of Nothofagus dombeyi, a keystone species of the Patagonian Andes, in secondary forests in Argentinian northern Patagonia, particularly addressing the role of disturbance through grazing by livestock at various intensities. We test the hypothesis that the regeneration of this tree species is favored by grazing impact and, thus, disturbance of the herb layer and soil surface. In support of our hypothesis, Nothofagus dombeyi regeneration was significantly higher in terms of individuals and height classes in moderately grazed forests. Multivariate analysis shows significant positive effects of moderate grazing pressure, herb layer cover, and the occurrence of bare soil on the regeneration of Nothofagus dombeyi. Our results show that an integration of livestock grazing and forest regeneration is possible and that agroforestry systems can be an adequate management option for stakeholders in the region. A grazing management can also be part of a forest fire prevention strategy. However, the regeneration success and grazing pressure should be continuously monitored.Fil: Zerbe, Stefan. Free University of Bozen-Bolzano; ItaliaFil: Storz, Stefanie T.. Universidad de Innsbruck; AustriaFil: Leitinger, Georg. No especifíca;Fil: Joelson, Natalia Zoe. Universidad de Innsbruck; AustriaFil: Bava, José. Centro de Investigación y Extensión Forestal Andino Patagónico; ArgentinaFil: Heinrichs, Steffi. No especifíca;Fil: Leuschner, Christoph. Centro de Investigación y Extensión Forestal Andino Patagónico; ArgentinaFil: Loguercio, Gabriel Angel. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Simon, Alois. No especifíca;Fil: Urretavizcaya, María Florencia. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Walentowski, Helge. No especifíca
Plantación de ciprés de la cordillera de 57 años de edad : una experiencia en el Parque Nacional Los Alerces
Full text linkEn el año 1947 la Administración Nacional de Parques instaló una parcela de reforestación con ciprés de la cordillera (Austrocedrus chilensis (D. Don) Pic. Sern. et Bizarri) de 700 m2, en un área degradada, próxima a Puerto Limonao (P.N. Los Alerces). La precipitación y temperatura anual es de 1.610 mm/año y 9,1 ºC, respectivamente. El suelo, derivado de pumita, es profundo (> 1 m), bien drenado, con textura franco arenosa y sin fragmentos gruesos. La secuencia de horizontes es A/ABw/Bw/C1/C2 y corresponde al Orden Andisol. La plantación se realizó con renovales extraídos del bosque aledaño, utilizando un distanciamiento aproximado de 2 m entre plantas. Durante el desarrollo del rodal no se realizaron reposiciones, podas, ni raleos. A los 57 años de edad, con una densidad de 1968 arb/ha y una altura dominante de 18,4 m, el diámetro medio cuadrático es 24,2 cm, el volumen 695 m3/ha y el crecimiento medio anual alcanzó los 12,2 m3/ha/año. La forma y sanidad general es buena. Esta experiencia de largo plazo, probablemente la más antigua de la región, permite comprobar el buen comportamiento y crecimiento del ciprés de la cordillera en una forestación.Fil: Loguercio, Gabriel Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Buduba, Carlos Guillermo. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: la Manna, Ludmila Andrea. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
The interior climate and its microclimatic variation of temperate forests in Northern Patagonia, Argentina
No full textAbstract
Knowledge on mesoclimatic zonation and microclimatic variations within mountain forest ecosystems is crucial for understanding regional species turnover and effects of climate change on these systems. The temperate mountain forests in the Andean region of South America are among the largest and contiguous natural deciduous forest areas in the world. Due to their pronounced disturbance regime and different successional stages, a climatic zonation combined with the characterisation of its microclimatic variation is important to identify thresholds of species occurrences.
We used micro-loggers to measure air temperature and relative humidity for one year at 40 measurement locations along longitudinal and elevation gradients in mountain forests in Northern Patagonia, Argentina. Our results unveil mesoclimatic patterns within these forests characterised by variations in temperature and vapour pressure deficit along the elevational gradient in general, but also at different times of the year. For example,
Austrocedrus chilensis
and
Nothofagus dombeyi
forests differed mainly by temperature and its diurnal range in the warmest months of the year. Also, differences between forest stands and gaps were more pronounced in the warmest months of the year and at lower elevations, with up to 2.5 K higher temperatures in the second half of the day in gaps. We found clear indications that shrubland of
Nothofagus antarctica
representing a successional stage after disturbances alters the mesoclimatic pattern, favouring forest fire ignition. Such mesoclimatic variations have a major influence on tree species turnover and ecological processes within these forest ecosystems.
The findings contribute to our understanding of the complex interplay between topography, climate, and vegetation in shaping the spatial patterns of species occurrences.Bundesanstalt für Landwirtschaft und Ernährung http://dx.doi.org/10.13039/501100010771Hochschule für angewandte Wissenschaft und Kunst (HAWK
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
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
La planificación del manejo forestal
No full textEl primer paso de un proyecto o programa de forestación es definir sus objetivos. Éstos pueden ser: generar ingresos a través de la producción de madera de uso industrial, la recuperación de suelos degradados o la protección y conservación de los recursos vegetales, del suelo, el agua y la fauna, entre otros. Pero en todos los casos en que la producción de un bien o servicio ambiental individual es el fin principal, debe considerársela desde un punto de vista integral.EEA BarilocheFil: Bava, José Omar. Universidad Nacional de la Patagonia (UNPSJB). Facultad de Ingeniería. Centro de investigación y Extensión Forestal Andino Patagónico; ArgentinaFil: Chauchard, Luis Mario. Administración de Parques Nacionales. Delegación Regional Patagonia; ArgentinaFil: Chauchard, Luis Mario. Universidad Nacional del Comahue. Asentamiento Universitario San Martín de los Andes; ArgentinaFil: Loguercio, Gabriel. Universidad Nacional de la Patagonia (UNPSJB). Facultad de Ingeniería. Centro de investigación y Extensión Forestal Andino Patagónico; ArgentinaFil: Mele, Uriel. Secretaría de Producción e Industria de Neuquén. Dirección General de Recursos Forestales; ArgentinaFil: Rusch, Veronica Elena. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; Argentin
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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