1,721,020 research outputs found
Syntaxonomical survey of Geranio-Cardaminetalia hirsutae: semi-natural therophytic vegetation of the Mediterranean Region
No full textBryosociological remarks on garrigue environments in Apulia region (southern Italy)
Full text linkA phytosociological study on the bryophyte communities of the xeric environments of Apulia Region was carried out. According the cluster analysis, the surveyed communities recognized in the context of the garrigue habitats are: Pleurochaeto squarrosae-Cheilotheletum chloropi, considered typical of the garrigues, Rhynchostegietum megapolitani and Pleurochaeto squarrosae-Tortuletum ruralis of the alliance Homathecio aurei-Pleurochaetion squarrosae; Tortello flavovirentis-Trichostometum crispuli and Tortelletum papillosissimae of the psammophytic alliance Tortellion flavovirentis; Weissietum controversae and Barbuletum convolutae of the alliance Grimaldion fragrantis
Updated and new insights on the coastal halophilous vegetation of southeastern Sicily (Italy)
Full text linkAn overview of the salt marsh vegetation of southeastern Sicily is here presented. On the basis of a total of 241 relevés, 8 classes and 32 plant communities have been identified, following the Braun-Blanquet phytosociological method. The salt marsh vegetation of southeastern Sicily is represented by aquatic communities of Ruppietea and Potamogetonetea, by helophytic communities of Phragmito-Magnocaricetea, by hygrophylous communities of Juncetea maritimi, by halophylous communities of Salicornietea fruticosae, by annual halo-nitrophylous communities of Saginetea maritimae, and finally by halophylous annual communities of Thero-Suaedetea splendentis. The plant communities belonging to Salicornietea fruticosae and Juncetea maritimi classes, were analysed through a numerical analysis (hierarchical clustering). The study also describes two new associations belonging to the Tamaricion africanae (Limbardo crithmoidis-Tamaricetum africanae) and Frankenion pulverulentae (Brizo minoris-Isolepidetum cernui) alliances
Contribution to the knowledge of Mediterranean wetland biodiversity: Plant communities of the Aquila Lake (Calabria, Southern Italy)
Full text linkAs part of researches undertaken on the aquatic and marsh vegetation of southern Italy, a study on the Aquila Lake, a small lake basin in southern Calabria near Rosarno (RC), is here presented. Overall, 86 phytosociological relevés were carried out. The phytosociological study allowed the identification of several aquatic and marsh phytocoenoses, many of which not yet known for the region. They are referable to the following 8 classes: Lemnetea minoris R. Tx. ex O. Bolòs & Masclans 1955, Potametea pectinati R.Tx. & Preising 1942, Phragmito australis-Magnocaricetea elatae Klika in Klika & Novák 1941, Agrostietea stoloniferae Oberdorfer 1983, Galio aparines-Urticetea dioicae Passarge ex Kopecký 1969, Molinio-Arrhenatheretea Tüxen 1937, Salici purpureae-Populetea nigrae Rivas-Martínez & Cantó ex Rivas-Martínez et al. 2001, Querco roboris-Fagetea sylvaticae Br.-Bl. & Vlieger in Vlieger 1937. A peculiar marsh vegetation is the Cladietum marisci Allorge 1922 ex Zobrist 1935 (habitat of Community interest, according to the EEC directive 43/92 - 7210 ∗Calcareous ferns with Cladium mariscus and species of the Caricion davallianae"). In the Aquila Lake, some rare aquatic plant communities highlight the importance of this biotope for biodiversity conservation. In particular, we found the pleustophytic associations Lemno-Spirodeletum polyrhizae Koch 1954, Lemno minoris-Hydrocharitetum morsus-ranae Passarge 1978 and the aquatic rooted vegetation of Nymphaeetum albae Vollm. 1947. Despite the heavy pressures on this area, the biotope harbours a well-differentiated and structured aquatic and marsh vegetation that allows the presence of a rich bird life, both sedentary and migratory. The area, privately owned, is not protected; hunting and fishing are practiced and water is pumped for irrigation with negative consequences on the integrity of the entire aquatic ecosystem. Because of its naturalistic peculiarities and its remarkable biodiversity, this biotope certainly deserves more attention and should be proposed as a protected area
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
Genetic structure of populations of Salvia ceratophylloides endemic to southern Calabria (southern Italy)
Full text linkAssessing the degree of genetic diversity and differentiation of rare or endangered endemic species is essential to evaluate the conservation status of populations and successively implement appropriate conservation strategies. We investigated the population structure of Salvia ceratophylloides Ard., a scapose hemicryptophyte endemic to Calabria (southern Italy), both to answer questions about its genetic structure and to determine whether the actual population size has undergone significant demographic changes in the near past. The data obtained from the census showed that the populations are characterised by a greater number of adult individuals than juveniles and are on declining. The genetic analysis carried out on 99 individuals from four populations of the species under study, shows a mean expected heterozygosity value of 0.50 and an overall differentiation value of 0.083. The population structure shows that the four studied populations are distinct genetic units, genetically linked to four different ancestral gene pools. Bayesian analysis based on ABC models indicates that the present populations underwent a significant reduction in size in the past. This corresponds to the demographic decline at the end of the 19th century, which according to the literature, was due to the strong anthropic pressure (agriculture, grazing, fire and plantations) of Reggio Calabria suburbs. We can therefore conclude that populations are not affected by inbreeding and low genetic diversity and that there is no immediate danger of genetic erosion, and that the problems associated with population decline, past and present, are exclusively due to anthropogenic causes
New data on the alien vascular flora of calabria (Southern Italy)
No full textNew data concerning the distribution of 21 non-native vascular species for Calabria (southern Italy) are presented. Agave filifera is reported for the first time in Europe (Canary Islands excluded), while Leucaena leucocephala subsp. glabrata and Senna corymbosa are founded for the first time in continental Italy. Saccharum biflorum is confirmed in Italian Peninsula, while Physalis angulata is a new exotic plant for southern Italy. Moreover sixteen other species are reported for the first time, confirmed or indicated with an updated naturalization status in Calabria
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
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