1,721,026 research outputs found
Fig. 1 in Lectotypification of taxa belonging to the "Festuca circummediterranea" group
No full textFig. 1. – Lectotypus of Festuca ovina subsp. laevis Hack. [Todaro s.n., W] [© Naturhistorisches Museum Wien. Reproduced with permission]Published as part of Foggi, Bruno, Quercioli, Claudia, Gennai, Matilde, Nardi, Enio & Signorini, Maria Adele, 2012, Lectotypification of taxa belonging to the "Festuca circummediterranea" group, pp. 221-228 in Candollea 67 (2) on page 224, DOI: 10.15553/c2012v672a2, http://zenodo.org/record/571895
The Nardus-rich communities in the northern Apennines (N-Italy): a phytosociological, ecological and phytogeographical study
Full text linkSecondary grasslands dominated by Nardus stricta are an anthropogenic vegetation type that occurs widely through the
Europe from lowlands to mountains. These communities have been recently recognized by the European Community as a habitat of
priority interest. The aim of the study is to perform a detailed and complete phytosociological scrutiny of this vegetation in the northern
Apennines. Further aims are to detect the factors controlling the floristic variation within these communities and to analyse the
variations of Nardus grasslands along a latitudinal gradient from the northern Alps to the southern Apennines. We processed a set of
134 phytosociological relevés from the northern Apennines through a cluster analysis based on Kendall’s tau dissimilarity measure.
Results showed the occurrence of two different associations of Nardus grasslands (Carlino caulescentis-Nardetum strictae and Violo
ferrarinii-Nardetum strictae). Relations between their floristic composition and environmental variables were detected through Redundancy
Analysis. The matrix of habitat factors included topographic variables and variables derived from Ellenberg’s indicator
values. Elevation was the factor explaining most of the floristic variation. From the comparison of 44 synoptic tables from the Alps,
Carpathians and Apennines, processed through a NMDS ordination, we detected two main phytogeographic and ecological thresholds
along the latitudinal gradient
Studying local species assemblages of salt-affected vegetation for monitoring Natura 2000 habitats
No full textThis study aims to characterize saline habitats of the Tuscan coast based on the Natura 2000 Habitats Directive 92/43/ECC. These habitats include Atlantic salt meadows (1330), Mediterranean salt meadows (1410) Mediterranean and thermo-Atlantic halophilous scrubs (1420), and Mediterranean salt steppes (1510). We compiled vegetation data from a total of 418 plots carried out during our own fieldwork (N = 157) and published scientific literature (N = 261). We performed a Linear Discriminant Analysis to associate species to habitats and used the phi coefficient of association to identify diagnostic species of each habitat. For each habitat, we provide a regional syntaxonomic framework, constant species, cover coefficients, diagnostic species (phi) and “typical species”. We identified groups of species, that we called “local assembly of typical species”, composed by species with a phi coefficient > 20 and/or a cover coefficient > 50 that can be used to identify the habitats and to monitor their conservation status at the local level. This study revealed differences in the “local assembly of typical species” among habitats, characterized by fewer species in habitats 1420 and 1510, and many species in habitats 1410 and 1310. Our results showed that the habitat 1510 was recognizable only for the high cover value of Limonium narbonense and, at least in Tuscany, its syntaxonomic attribution to the order Limonietalia is uncertain. We tested this approach only for a few habitats, but a broader applicability based on other habitats is desirable
Spatial patterns of coastal dune plant diversity reveal conservation priority hotspots in and out a network of protected areas
Full text linkEffective conservation planning requires identifying priority hotspots to allocate resources. To preserve biodiversity, it is crucial to consider α, and γ-diversity and protect ecologically unique sites, which can host uncommon and irreplaceable species assemblages that would be lost if only species-rich sites were protected. Coastal dunes, hosting highly specialized plant communities, are among the most threatened ecosystems worldwide. In this study, we identified conservation priority hotspots to assess the effectiveness of the network of protected areas in coastal dunes of Tuscany (central Italy), using data on plant communities collected in 506 plots. We additively partitioned -diversity in its and components, observing a significant variation at all spatial levels only for dune species. In terms of -diversity, we found that Northern protected sites were richer in dune species, while synanthropic and alien species were equally present inside and outside protected areas. By partitioning the total -diversity into its components (replacement and richness difference), we found a prevalence of replacement for dune species, indicating the most unique sites as the ones to favor for conservation. Unique sites were identified through Local Contributions to Beta-Diversity and their conservation value was determined by their species composition and the relationship with landscape variables. Unique sites with high conservation value were only partly protected, while some protected sites were altered and required restoration. Our approach proved effective for identifying the most unique sites, indicating some issues in the existing protected network, while providing valuable information on sites to prioritize for future conservation actions
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
New technologies for plant food processing in the Gravettian
No full text“Plant Resources in the Palaeolithic” is a research project focused on the technologies for plant food processing as documented by use-wear traces and plant residue on grinding tools found in European sites. Many researchers have been involved in the project, which encompasses the fields of archaeology, botany and food processing technologies, within the context of the history of European Prehistoric societies. The first study was carried out on use-wear traces and plant remains recovered from grinding tools from the sites of Bilancino (Italy), Kostienki 16 (Russia) and Pavlov VI (Czech Republic), dating to the Middle-Upper Palaeolithic (Gravettian and Gorotsovian) around 28,000e30,000 cal BP. The results demonstrated that vegetable food processing and the production of flour was a common practice across Europe from at least 30,000 years ago and that flour, a high-energy food, was a component of the food economy of mobile hunter gatherers. Flour production and consumption imply multi-step processing from harvesting to cooking to obtain a suitable and digestible food, and that this was part of an Upper Paleolithic behavioural package. This paper presents new data from two Gravettian pestles, found at Grotta Paglicci e level 23a (Southern Italy) and at Dolni Vestonice I (Czech Republic), which furnish further information about plant exploitation and the technologies related to plant food processing
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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