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Medioambiente in IberoamErica : vision desde la fisica y la quimica en los albores del siglo 21 : tomo 2
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Medioambiente in Iberoamerica : vision desde la fisica y la quimica en los albores del siglo 21 : tomo 2
No full textInfluencia de las propiedades edáficas sobre el crecimiento de Schinopsis balansae Engler en el Parque Chaqueño Húmedo (Argentina) = Influence of soil properties on the growth of Schinopsis balansae Engler in the Humid Parque Chaqueño (Argentina)
Full text linkSchinopsis balansae (quebracho colorado chaqueño) es una especie dominante característica del Chaco Húmedo Argentino, que se desarrolla en suelos con limitaciones físicas escasamente reversibles, que sólo las especies arbóreas de alta rusticidad pueden colonizarlos. El objetivo del trabajo fue analizar las propiedades edáficas que pueden influir sobre el crecimiento y desarrollo de reforestaciones con S. balansae en la ecorregión del Chaco Húmedo argentino. Al efecto fueron seleccionados cuatro sitios forestados con S. balansae en la ecorregión del Chaco Húmedo en el Parque Chaqueño Oriental. Las plantaciones de la misma franja etaria (10 - 12 años), similar distancia de plantación (4 m x 4 m) y estado sanitario. En cada sitio se seleccionaron 12 árboles representativos, midiéndose el diámetro altura de pecho (DAP) y la altura de fuste, tomándose muestras de suelo a 0 a -10; -10 a -25; -25 a -55; y -55 a -115 cm de profundidad. Se realizaron las siguientes determinaciones: textura; densidad aparente (Da); porosidad capilar (Pmc); pH; conductividad eléctrica (CE); materia orgánica edáfica (MOS); Ca2+, K+ y Na+ de cambio; y relación de adsorción de sodio (RAS). Se concluye que las propiedades edáficas condicionantes para el crecimiento y desarrollo de forestaciones con quebracho colorado chaqueño son la salinidad (positivamente, relacionada con la conductividad eléctrica) y negativamente la textura (exceso de arcilla) que afectarían a la instalación y crecimiento del quebracho colorado chaqueño; aunque en profundidad se prefiere un aumento de la RAS, pero manteniéndose una moderada salinidad.Schinopsis balansae (quebracho colorado chaqueño) is a dominant species, characteristic of the humid Chaco (Argentina) where the quality of the soil is often low, primarily due to physical limitations (poor drainage), i.e., where only tree species of high rusticity can colonize. The objective of the study was to analyze the edaphic properties that may influence the growth and development of reforestation using quebracho (S. balansae) in the Argentine humid Chaco ecoregion. For this purpose, four sites forested with plantations of the same age (years 10-12), similar distance (4 x 4 m2) and health status of S. balansae were selected. In each site, twelve individuals were measured at their diameter at height of chest (DAP) and trunk length (H), and its soil sampled at 0 to - 10; -10 to - 25; -25 to - 55; and - 55 to - 115 cm depth. The following parameters were measured: texture; bulk density (Da); capillary porosity (Pmc); pH; electrical conductivity (CE); soil organic matter (MOS); exchangeable Ca2+, K+ and Na+; and (RAS) sodium adsorption ratio. It is concluded that the edaphic properties conditioning the growth and development of afforestations with quebracho colorado chaqueño are salinity (positively, related to electrical conductivity) and texture (negatively, excess of clay) that would affect the installation and growth of the quebracho colorado chaqueño; even though, concerning depth, an increase in de RAS is preferred, though keeping a moderate salinity.EEA CorrientesFil: Prause, Juan. Universidad Nacional del Chaco Austral; ArgentinaFil: Fernandez Lopez, Carolina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Corrientes; ArgentinaFil: Gallardo Lancho, J.F. Consejo Superior de Investigaciones Científicas (C.S.I.C.). Instituto de Recursos Naturales y Agrobiología de Salamanca; Españ
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
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