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Caracterização fitossociológica das bromeliaceas epifíticas e suas relaçoes com os fatores geomorfologicos e pedologicos da planície do rio Iguaçu, Paraná, Brasil
Get PDFThe forests of the Iguaçu river floodplain, which are part of two distinct phytogeographic units, Mixed Ombrophillous Forest and Semidecidual Seasonal Forest, are currently very modified. This alteration occurred due to historical factors and contemporaneous anthropic action. Epiphytic bromeliads, due to its specific substrate dependence and its strategy to obtain nutrients through their trichomes, are considered indicators of environmental condition alterations. Taking into account the reduced amount of research using this approach and the inexistence of systematic and continuous works with bromeliads along Brazilian's rivers, it was studied the floristic and the structure of the forests, and the communities of bromeliads present on aggradation and degradation surfaces of the compartments established from the first until the third highland of Paraná. In each area, the qualitative and quantitative data of bromeliads were related to the physical factors of the environment, like streambed type, height of the border, predominant geomorphic sites and soil water saturation. It was registered a total of 14 species of bromeliads belonging to six genera, which presented significant differences in diversity and abundance among the compartments. Macroclimate was the most important factor to define the differences between the two phytogeographic units, besides the conservation state of the forest which was a very changeable characteristic among the surfaces. Locally, bromeliads reacted to the high taxes of atmosphere humidity, created by the proximity of the river, by the existence of geomorphic concaved sites and by soils with low permeability that make possible the accumulation of water. They reacted also to the stratification of the forest and the presence of high trees that represent more surface and longer time of exposition of the substrate for the colonization. On phorophytes, the bromeliads occurred in intervals of very varied heights, indicating that the small height of the forest and the existence of forest gaps created by the presence of the river and the presence of soils containing high content of water, influenced the vertical stratification standard. Seedlings could be related to the amount and diversity of existing adults in the area, as well as, to the available environmental humidity. The beginning of the crown was the local of establishment of tank bromeliads and zoochoric bromeliads. This could be related to the biggest weight of the individuals and to the place of landing of avian dispersers. Aechmea recurvata, Wittrockia cyathiformis and Billbergia nutans, beyond Vriesea reitzii, were chosen as indicators of vegetation in advanced state of regeneration. Beside that, Aechmea distichantha, Tillandsia tenuifolia, Tillandsia usneoides and Vriesea friburgensis were considered the pioneers in the occupation of trees that grow in the most recent sediments of the aggradation surfaces. T. usneoides showed to be the most important element for mapping the humid environment in the lowland, but only in open places, where the evaporation and the humidity removal are constant
Diversidade e distribuição espacial de bromélias epifíticas em diferentes estádios sucessionais da Floresta Ombrófila Densa - Ilha de Santa Catarina
Get PDFDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas.Foram amostradas bromélias epifíticas em quatro estádios sucessionais da Floresta Ombrófila Densa. Elas foram diferenciadas em plântulas e espécies identificáveis, e o critério de registro foi presença/ausência em intervalos de 2 metros de altura de 60 forófitos por estádio sucessional. Foram determinadas 14 espécies de bromélias epifíticas, sendo 5 no estádios de arvoretas, 8 no arbóreo pioneiro e 11 na floresta secundária. Houve um aumento do número de indivíduos e de espécies de forófitos colonizados por plântulas nos sucessivos estádios sucessionais, sugerindo um aumento na disponibilidade de diásporos e diminuição da mortalidade de plântulas com aumento de umidade. Nos estádios arbóreo pioneiro e de floresta secundária houve correlação significativa na distribuição vertical de 4 espécies de bromélias
Epifitos vasculares das florestas do rio Tibagi, Parana
No full textSupervisores : Prof. Dr. Franklin Galvão e Prof. Dr. Gustavo Ribas CurcioRelatorio (pos-doutorado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Engenharia Florestal. Defesa: Curitiba, 24/03/2009Inclui bibliografiaÁrea de concentração : Conservação da naturezaEpífitos vasculares, que pertencem a 83 diferentes famílias botânicas, necessitam principalmente, de alta umidade relativa para sua sobrevivência e diversificação. Em ambientes fluviais, combinações variadas de umidade e luminosidade propiciam hábitats diversos para estas plantas. Este trabalho teve como objetivos avaliar a composição florística e a distribuição dos epífitos vasculares ao longo do rio Tibagi e analisar suas relações com fatores climáticos, geomorfológicos, pedológicos e estruturais da floresta. Foram registradas 188 espécies, pertencentes principalmente às famílias Orchidaceae, Polypodiaceae e Bromeliaceae. Apenas Pleopeltis pleopeltifolia ocorreu em todas as 23 áreas de estudo. É elevado o grau de substituição das espécies ao longo do rio, indicando a importância das comunidades para a conservação destas plantas no estado do Paraná. A similaridade foi maior entre as áreas mais próximas geograficamente, formando-se, de montante para jusante do rio, a região do alto, médio e baixo Tibagi que, respectivamente, pertencem à região de Floresta Ombrófila Mista, ecótono e Floresta Estacional Semidecidual. Estas apresentam distintas riquezas e composições florísticas, como a ecotonal, onde foi registrado número máximo de espécies em clima transicional e florestas mais bem conservadas. O diâmetro das árvores, significativamente relacionado com a riqueza, é responsável pela ampliação da diversidade alfa, enquanto a diversidade beta é resultado da heterogeneidade ambiental que, nas áreas estudadas, se expressa pela associação de condições macro e microclimáticas com padrões geomorfológicos
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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