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Evaluation of lichen diversity as an indicator of environmental quality in the North Adriatic submediterranean region.
No full textIn 2000, a standardized sampling protocol was developed by a group of European researchers to provide a repeatable and
objective strategy for mapping lichen diversity as an indicator of environmental changes; this protocol is nowadays adopted in
the guidelines to air quality bioindication in Italy.
The present paper shows the results of a study of epiphytic lichen diversity performed according to both the new protocol
and the standard methodology previously used in Italy; diversity values are based on frequency counts of all lichen species
within particular sampling grids positioned on the trunks and divided in subunits. The survey was carried out in 61 sampling
sites of two areas of the Friuli Venezia Giulia region (Italy) and Slovenia, characterized by similar climatic conditions and a
wide range of anthropic pressure. Biodiversity values obtained following the two sampling methods are highly statistically
correlated; this suggests an interpretative continuity of lichen diversity data for biomonitoring purposes. Lichen communities
and diversity values occurring in natural areas, far from heavy human influences, are investigated by means of multivariate
analysis of floristic releve ́s of 11 sites. Diversity values scored in natural areas are rather variable, and are mainly influenced by
the different vegetation types, Parmelion communities having lower diversity values than communities with Xanthorion
elements. Evaluation scales of environmental alteration based on lichen diversity in the North Adriatic submediterranean
bioclimatic area are provided. Some critical aspects of the sampling strategies are discussed
Uso di Artropodi quali bioindicatori e bioaccumulatori nel monitoraggio di suoli inquinati nella Valle delle Noghere (Trieste).
No full text
Biomonitoraggio di metalli in traccia tramite licheni in aree a rischio del Friuli-venezia Giulia.
Full text linkBIOMONITORING OF TRACE METALS BY LICHENS IN HIGH-RISK AREAS OF FRIULI-VENEZIA GIULIA (NE ITALY). This study is based on the concentrations of 16 metals in peripheral parts of the thalli of the lichen Xanthoria parietina, collected on trees satisfying standard conditions in 155 stations located in the lowlands of
Friuli-Venezia Giulia (NE ltaly), previously selected as potential high-risk areas by Regional Authorities. The interpretation of metal concentrations is based upon two maps, showing, for each metal, its distributional pattern and the degree of deviation from background (natural) conditions. The latter has been estimated through a seven-class scale based on the percentile distributions of several hundreds measurements of metal concentrations carried out in foliose lichens throughout Italy during the last ten years, using similar methods.
The joint occurrences of all metals in the stations are synthetized by maps based on three indices, an index of naturality (indicating the number of metals with concentrations within normai conditions), an index of environmental alteration (indicating the number of metals strongly deviating from the norm), and an index of potential toxicity (derived from that of alteration, with each metal weighed according to its toxicity). The Central-Southern part of the Province of Udine is the most severely affected by metals in general, while in several other stations single metals strongly deviate from normal conditions. These sites are suggested to the Regional Authorities as focal points for instrumental monitoring of environmental pollution. The introduction includes some basic considerations about epistemological, methodological and terminological matters related to the use of biomonitoring techniques
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
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