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Ecological patterns of commercial fisheries in the floodplain: hydro-geomorphological variation. Identifying ecologically relevant sites for conservation.
Get PDFFil: Rabuffetti, Ana Pía. Universidad Nacional del Litoral. FCM; Argentina.El objetivo central de este proyecto es ""determinar patrones de uso de la llanura aluvial de alevines-juveniles de las principales especies ícticas comerciales del sistema en función de las características hidro-geomorfológicas de la planicie aluvial del río Paraná en su tramo medio, ante diversas unidades geomorfológicas y niveles de conexión y desconexión"". Esta determinación permitirá identificar puntos estratégicos para la conservación de las especies comerciales, e identificar hábitats prioritarios para la conservación en función de los procesos ecosistémicos críticos (e.g. zonas de alevinaje, reproducción). Los conocimientos generados tienden a asegurar la sostenibilidad de las pesquerías del río Paraná en el largo plazo. Se considera que la información generada podría ser de utilidad para el desarrollo de un manejo sustentable del recurso pesquero en la región. Por lo que, resultaría de interés para los diversos tomadores de decisión involucrados en el manejo y explotación del recurso íctico, las comunidades de pescadores, y los clubes de pesca. Los conocimientos adquiridos puedan ser utilizadas para avanzar hacia un manejo ecosistémico de la pesca, con el fin de asegurar la sustentabilidad de los recursos y las pesquerías como sistemas socio-ecológicos ante posibles impactos antrópicos y de variabilidad y cambio climático.""The principal aim of this project is to ""determine patterns of use of the alluvial plain by fingerlings-juveniles-adults of the fisheries of the system based on the hydro-geomorphological characteristics of the floodplain in the Middle Paraná River, iconsidering various geomorphological units and different hidrological levels -of connection and disconnection-"". This determination will make it possible to identify strategic points for conservation of the commercial fish species, identifing priority habitats for conservation based on cientific criteria, being this critical ecosystem processes (e.g. nursery areas, reproduction). The knowledge generated tends to ensure the sustainability of the fisheries of the Paraná River in the long term. For this we considered that the information generated could be useful for the development of a sustainable management of the fishing resource in the region (Santa Fe state). Therefore, it would be interesting to differents stockholders -decision makers- involved in the management and exploitation of fish resource, the fishing communities, and the fishing clubs. The knowledge acquired can be used to promove an ecosystem management of fisheries, in order to ensure the sustainability of resources and fisheries as socio-ecological complex systems in the face of possible anthropogenic impacts and climate change (future scenarios)
Influence of climate variability on the composition of the fish community in the Middle Paraná River
No full textFil: Rabuffetti, Ana Pia. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentina.En esta tesis se evaluó el efecto de fluctuaciones climáticas ocurridas en la cuenca del Plata durante los últimos 100 años sobre las pesquerías comerciales en el tramo medio del río Paraná. Se estableció la significación de la componente hidroclimática comparada con la de otras variables de origen esencialmente antrópico, sobre los cambios poblacionales del ensamble de peces de importancia comercial. Los resultados permitieron inferir la influencia probable sobre esas especies de diversos escenarios climáticos futuros propuestos para la cuenca. Se analizaron más de 8 décadas de información (1934-2016) de las especies comerciales más frecuentes y abundantes, proveniente tanto del cauce principal del rio Paraná como de su extensa planicie de inundación. Los diversos atributos examinados (biomasa, talla, factor de condición), variaron a lo largo del tiempo. Sus aumentos/disminuciones a largo y corto plazo se produjeron en íntima relación con las fluctuaciones hidroclimáticas cuantificadas mediante un total de 18 variables. Se determinaron efectos positivos sobre la ictiofauna durante períodos húmedos (1900-1940 y 1970-2000), cuando se incrementó la frecuencia de ocurrencia de las inundaciones de primavera-verano de gran intensidad y duración (frecuencia media de 4-6 años para el período completo). Se registró un incremento durante las últimas 2 décadas de la incidencia de la componente antrópica (cuantificada mediante 9 variables). Las condiciones hidroclimáticas futuras predichas por modelos disponibles, serían desfavorables para el ensamble comercial ya que disminuirían caudales y conectividad y, con ello, el éxito reproductivo de las especies con sus consecuentes capturas (en particular de los grandes migradores).This thesis deals with the effects of climatic fluctuations occurred in La Plata basin during the last 100 years on the fisheries of the Paraná River in its middle reach. The significance of hydroclimatic variables compared with others accounting for anthropic impacts on the population changes of commercial species, was appraised. The results enabled to approach the probable influence on the ichthyofauna of distinct future climatic scenarios advanced for the basin. Data series covering more than 8 decades (1934-2016) of the most frequent and abundant commercial species inhabiting the main channel as well as the nearby large floodplain of the Paraná River, were used. Fish attributes (biomass, size -Ls-, body condition factor) changed over time. Their long (short) term increments/reductions were closely related with fluctuations of 18 hydroclimatic variables. Positive effects on the ichthyofauna were recorded during humid periods (1900-1940 and 1970-2000), when the frequency of large spring-summer floods increased (these floods had an average frequency of 4-6 years along the whole studied period). An increment of the anthropic incidence (accounted through 9 variables), was recorded during the last two decades. Future hydroclimatic conditions as predicted by available models, would not be adequate for commercial fisheries since a decrement of discharges and hydrological connectivity is expected and, thus, of the reproductive success and catches of the different species (particularly the large migrants).Consejo Nacional de Investigaciones Científicas y Técnica
Influence of climate variability on the composition of the fish community in the Middle Paraná River
No full textFil: Rabuffetti, Ana Pia. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentina.En esta tesis se evaluó el efecto de fluctuaciones climáticas ocurridas en la cuenca del Plata durante los últimos 100 años sobre las pesquerías comerciales en el tramo medio del río Paraná. Se estableció la significación de la componente hidroclimática comparada con la de otras variables de origen esencialmente antrópico, sobre los cambios poblacionales del ensamble de peces de importancia comercial. Los resultados permitieron inferir la influencia probable sobre esas especies de diversos escenarios climáticos futuros propuestos para la cuenca. Se analizaron más de 8 décadas de información (1934-2016) de las especies comerciales más frecuentes y abundantes, proveniente tanto del cauce principal del rio Paraná como de su extensa planicie de inundación. Los diversos atributos examinados (biomasa, talla, factor de condición), variaron a lo largo del tiempo. Sus aumentos/disminuciones a largo y corto plazo se produjeron en íntima relación con las fluctuaciones hidroclimáticas cuantificadas mediante un total de 18 variables. Se determinaron efectos positivos sobre la ictiofauna durante períodos húmedos (1900-1940 y 1970-2000), cuando se incrementó la frecuencia de ocurrencia de las inundaciones de primavera-verano de gran intensidad y duración (frecuencia media de 4-6 años para el período completo). Se registró un incremento durante las últimas 2 décadas de la incidencia de la componente antrópica (cuantificada mediante 9 variables). Las condiciones hidroclimáticas futuras predichas por modelos disponibles, serían desfavorables para el ensamble comercial ya que disminuirían caudales y conectividad y, con ello, el éxito reproductivo de las especies con sus consecuentes capturas (en particular de los grandes migradores).This thesis deals with the effects of climatic fluctuations occurred in La Plata basin during the last 100 years on the fisheries of the Paraná River in its middle reach. The significance of hydroclimatic variables compared with others accounting for anthropic impacts on the population changes of commercial species, was appraised. The results enabled to approach the probable influence on the ichthyofauna of distinct future climatic scenarios advanced for the basin. Data series covering more than 8 decades (1934-2016) of the most frequent and abundant commercial species inhabiting the main channel as well as the nearby large floodplain of the Paraná River, were used. Fish attributes (biomass, size -Ls-, body condition factor) changed over time. Their long (short) term increments/reductions were closely related with fluctuations of 18 hydroclimatic variables. Positive effects on the ichthyofauna were recorded during humid periods (1900-1940 and 1970-2000), when the frequency of large spring-summer floods increased (these floods had an average frequency of 4-6 years along the whole studied period). An increment of the anthropic incidence (accounted through 9 variables), was recorded during the last two decades. Future hydroclimatic conditions as predicted by available models, would not be adequate for commercial fisheries since a decrement of discharges and hydrological connectivity is expected and, thus, of the reproductive success and catches of the different species (particularly the large migrants).Consejo Nacional de Investigaciones Científicas y Técnica
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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