1,720,990 research outputs found
Past landscape features may be captured by historical floristic data. A case study in northern Italy
Full text linkHistorical floras, i.e. lists of plant species recorded in a given geographical area, are not usually considered for capturing past landscape features. In this study, we tested the usefulness of the simultaneous use of historical floristic data and a coeval topographic map to evaluate the main features of the past vegetation landscape and the potential of such data in change detection. Our study site was the Monte Fumaiolo area (northern Italy), where historical floristic data were independently recorded by two famous botanists during the 1930s. Past floristic data were then compared with current cartographic and vegetation data. Despite the fact that the two authors explored a comparable area, they significantly differed in the use of toponyms and in the distribution of floristic records among toponyms. This is reflected by a low floristic similarity at the toponym level between the two data sets. Nevertheless, the species classification into ecological categories allowed to highlight how the two authors recorded similar information on the landscape features. However, the use of these floristic data may have some flaws in landscape change detection.</p
Il racconto di viaggio del botanico Antonio Bertoloni (1775-1869)
No full textLungo la Futa, osservando piante, paesaggi, genti
La dimensione storica delle idrofite invasive: un database condiviso, potenzialità e studi fatti
No full textFlora delle Balze di Verghereto, Monte Fumaiolo e Ripa della Moia
No full textViene presentata la flora vascolare di questo sito della Rete Natura 2000, esteso per circa 25 km 2 nel sud-est
dell’Emilia-Romagna, alla testa delle valli del Tevere, del Savio e del Marecchia. Il sito è stato da lungo tempo oggetto di numerosi studi botanici; l’elenco qui proposto è basato su flore e segnalazioni floristiche databili fra l’inizio del 1800 e i giorni nostri. Sono stati registrati 689 taxa specifici e sottospecifici, appartenenti a 99 famiglie, delle quali le piú rappresentate sono Asteraceae (14%), Poaceae (9%) e Fabaceae (8%). Alcune specie qui rinvenute meritano un cenno, essendo al limite del loro areale italiano: Diphasiastrum tristachyum, Geranium palustre, Rosa glauca, R. villosa, Ribes multiflorum, non sempre confermate in tempi recenti. La flora ha una
sovrapposizione del 93% con quella del limitrofo Parco Nazionale delle Foreste Casentinesi. Si conferma la rilevante ricchezza biologica dell’area, seconda per importanza, a livello romagnolo, solo al Parco Nazionale delle Foreste Casentinesi.We present the vascular flora of this Natura 2000 site, situated in the south-eastern part of the Emilia-Romagna region. It occupies a mountainous area of about 25 km 2 in the upper part of the valleys of the rivers Tiber, Savio and Marecchia. Since a long time, this area has been the object of numerous botanical investigations; the list here proposed is based on floras and floristic notes compiled between the early 1800 and the present days. 689 specific and infraspecific taxa were registered, belonging to 99 families; the most represented ones are Asteraceae (14%), Poaceae (9%) and Fabaceae (8%). Some species here found are quite notable, being at the margin of their Italian range: Diphasiastrum tristachyum, Geranium palustre, Rosa glauca, R. villosa, Ribes multiflorum. They were not always confirmed in recent times. The flora has an overlap of 93% with that of the adjacent Parco Nazionale delle Foreste Casentinesi. We confirm the very notable biological richness of the area, which, in Romagna, is the second most important one after the Foreste Casentinesi National Park
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
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
- …
