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Catalogue of the Naturalized Flora of Taiwan
No full textThis study was conducted in years 2000 to 2003 to compile a comprehensive list of
naturalized species with background information, including origins, life forms, habits, usages, year of
the first collection, and status. Major herbaria (TAI, HAST, TAIF, and NCKU) were visited to
examine specimen records. Relevant publications and reliable websites and many other resources were
also examined extensively for background information. Total 341 species in 222 genera and 60
families were documented as naturalized in Taiwan, representing 7.9% of the local flora. Besides, 25
species were considered as possibly naturalized due to insufficient evidences. A large portion (90.6%)
of species reported here, were reported as “weeds” in other countries. Almost a half of the naturalized
species (48.3%) were introduced from Americas
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
Invasion of Rubus praecox (Rosaceae) is promoted by the native tree Aristotelia chilensis (Elaeocarpaceae) due to seed dispersal facilitation
No full textSeed dispersal facilitation among plant neighbours can be defined as an increase in the number, distances, and/or places reached by a plant’s seeds that is due to the presence of co-fruiting plant neighbours with which it shares seed dispersers. Many cases of this phenomenon have been described among native species and some also among introduced invasive species. Moreover, facilitation of native species recruitment by non-native fleshy-fruiting trees has been reported. Surprisingly, seed dispersal facilitation of exotic species by native species is either less common or has not been properly documented so far. Casual observation of secondary vegetation in La Araucanía Region, Chile, suggests that more individuals of exotic fleshy-fruiting bird-dispersed Rubus praecox (Rosaceae) are established under the native fleshy fruiting bird-dispersed subdioecious tree Aristotelia chilensis (Elaeocarpaceae) than under other native dry-fruiting tree species in the same areas. To assess whether these observation-suggested differences are statistically significant, two plots were sampled for interspecific associations between Rubus and Aristotelia and between Rubus and the most common dry-fruiting monoecious tree -Lomatia hirsuta (Proteaceae). The first important conclusion from this study is that invasive Rubus is substantially more common under both focal tree species than in open grasslands. Second, Rubus is associated more strongly with fleshy-fruiting Aristotelia than with dry-fruiting Lomatia in this landscape. Additionally, the frequency of Rubus is higher under Aristotelia fruiting (female or hermaphroditic) trees. Management implications are discussed
La invasión de Rubus praecox (Rosaceae) es promovida por el árbol nativo Aristotelia chilensis (Elaeocarpaceae) debido a la facilitación de la dispersión de semillas
Get PDFSeed dispersal facilitation among plant neighbours can be defined as an increase in the number, distances, and/or places reached bya plant’s seeds that is due to the presence of co-fruiting plant neighbours with which it shares seed dispersers. Many cases of thisphenomenon have been described among native species and some also among introduced invasive species. Moreover, facilitationof native species recruitment by non-native fleshy-fruiting trees has been reported. Surprisingly, seed dispersal facilitation of exoticspecies by native species is either less common or has not been properly documented so far. Casual observation of secondaryvegetation in La Araucanía Region, Chile, suggests that more individuals of exotic fleshy-fruiting bird-dispersed Rubus praecox(Rosaceae) are established under the native fleshy fruiting bird-dispersed subdioecious tree Aristotelia chilensis (Elaeocarpaceae)than under other native dry-fruiting tree species in the same areas. To assess whether these observation-suggested differences arestatistically significant, two plots were sampled for interspecific associations between Rubus and Aristotelia and between Rubus andthe most common dry-fruiting monoecious tree –Lomatia hirsuta (Proteaceae). The first important conclusion from this study is thatinvasive Rubus is substantially more common under both focal tree species than in open grasslands. Second, Rubus is associatedmore strongly with fleshy-fruiting Aristotelia than with dry-fruiting Lomatia in this landscape. Additionally, the frequency of Rubusis higher under Aristotelia fruiting (female or hermaphroditic) trees. Management implications are discussed.La facilitación de la dispersión de las semillas entre plantas vecinas se puede definir como un incremento en el número, distancia, y/olugares alcanzados por las semillas de una planta debido a la presencia de plantas vecinas que co-fructifican y con las que la especiecomparte dispersores de semillas. Se han descrito muchos casos de este fenómeno entre especies nativas y algunas también entre especiesintroducidas invasoras. Además, se ha informado de la facilitación del reclutamiento de especies nativas por árboles no-nativos de frutocarnoso. Sorprendentemente, la facilitación de la dispersión de semillas de las especies exóticas por especies nativas es menos común, ono ha sido debidamente documentada hasta el momento. La observación casual de la vegetación secundaria en la Región de la Araucanía,Chile, sugiere que más individuos de la especie exótica Rubus praecox (Rosaceae), cuyos frutos carnosos son dispersados por las aves, seestablecen bajo el árbol nativo Aristotelia chilensis (Elaeocarpaceae) que también posee frutos carnosos, que bajo otra especies de árbolesnativos con frutos secos en las mismas áreas. Para evaluar si las diferencias de observación sugeridas son estadísticamente significativas,se muestrearon dos parcelas para estudiar las asociaciones interespecíficas entre Rubus y Aristotelia y entre Rubus y el árbol más comúnde frutos secos –Lomatia hirsuta (Proteaceae). La primera conclusión importante de este estudio es que la invasora Rubus es mucho máscomún bajo ambas especies focales que en pastizales abiertos. En segundo lugar, Rubus se asocia más fuertemente con Aristotelia subdioicacon frutos carnosos que con la especie monoica de frutos secos Lomatia,en este paisaje del sur de Chile. Además, la frecuencia de Rubuses mayor bajo árboles productores de frutos de Aristotelia (femeninos o hermafroditas). Se discuten las implicaciones para la gestión de laespecie invasora
Limited seed dispersal may explain differences in forest colonization by the Japanese raisin tree (Hovenia dulcis Thunb.), an invasive alien tree in Southern Brazil
Get PDFThe Japanese raisin tree (Hovenia dulcis) is an invasive tree in South American forests, which produces capsuled fruits attached to peduncles that grow thick and fleshy when ripe. Frugivorous birds have been cited as dispersal agents of H. dulcis. The spread of H. dulcis propagules to non-invaded sites was evaluated at a local spatial scale in deciduous forests in Southern Brazil, in order to propose management strategies to prevent the arrival of propagules of such species in non-invaded sites. Seed arrival by birds was assessed by installing five 0.6 x 0.6 m seed traps in each 10 x 10 m plots installed in non-invaded sites at different distances from invaded sites. Seed arrival was also compared between control plots and plots where all H. dulcis trees were felled within a 30m radius from the center of plots. A limitation in short distance seed dispersal by birds was observed in the study area. There was a negative exponential relationship between number of seeds and distance from H. dulcis trees to non-invaded sites and a positive exponential dependence of the number of seeds found in seed traps on the basal area of H. dulcis. The felling of H. dulcis trees was effective in reducing the arrival of seeds in non-invaded sites, resulting in a significantly smaller number of seeds in managed plots than in control plots.A uva-do-Japão (Hovenia dulcis Thunb.) é uma espécie exótica invasora em florestas na América do Sul que produz infrutescências compostas por frutos secos aos quais estão presos pedúnculos que se tornam doces e carnosos quando maduros. Espécies de aves frugívoras são citadas como agentes dispersores de H. dulcis. A chegada de sementes de H. dulcis em sítios não-invadidos foi avaliada em escala espacial local em área de Floresta Estacional Decidual no sul do Brasil, com o intuito de propor estratégias de manejo para conter a colonização por H. dulcis nesses sítios. A chegada de sementes foi avaliada por meio de coletores de sementes instalados em sítios não-invadidos, localizados a diferentes distâncias de sítios invadidos. A chegada de sementes também foi comparada entre parcelas controle e parcelas submetidas ao corte de árvores de H. dulcis em um raio de 30 metros ao redor das mesmas. Detectou-se uma limitação na dispersão de sementes de H. dulcis por aves a curtas distâncias na área de estudo. Foi observada uma relação exponencial negativa entre o número de sementes e a distância de árvores de H. dulcis em sítios não-invadidos, enquanto uma relação exponencial positiva foi encontrada entre o número de sementes e a área basal das árvores amostradas. A eliminação de árvores de H. dulcis foi efetiva para reduzir a chegada de sementes em sítios não colonizados pela espécie, havendo um menor número de sementes em parcelas submetidas ao corte do que em parcelas controle.Fil: Dechoum, Michele. Universidade Federal de Santa Catarina; BrasilFil: Rejmánek, Marcel. University of California at Davis; Estados UnidosFil: Tarabini Castellani, Tania. Universidade Federal de Santa Catarina; BrasilFil: Zalba, Sergio Martín. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Grupo de Estudios en Conservación y Manejo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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
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