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Relation between some environmental parameters and Santolina etrusca (Lacaita) Marchi et D'Amato in stream beds of central Italy
No full textStudio preliminare su distribuzione ed ecologia di Santolina etrusca (Lacaita) Marchi et D'Amato
No full textEcology of soil lichens from Pliocene clay badlands of central Italy in relation to geomorphology and vascular vegetation
No full textThe terricolous lichen communities occurring under a temperate sub-arid to sub-humid climate
(mean annual rainfall about 750 mm) on Pliocene clay soils of southern Tuscany (central Italy) are
similar to those reported for arid or sub-arid areas, with mean annual rainfall around 200 mm. The
distribution of these communities is influenced by the availability of bare soil and percentage cover
of vascular plants. Where vascular communities are more important and pedogenetic processes lead to the development of more structured and evolved soils, pioneer lichen communities of the Toninio-Psoretum decipientis are replaced by communities such as that of Cladonietum convolutae, which are more capable of competing for light and nutrients with dense communities of tall grasses such as Bromus erectus. The distribution patterns of Artemisia cretacea and B. erectus among vascular plants, and Fulgensia fulgens and Cladonia rangiformis among lichens, account for most of the variability in vascular and lichen communities, respectively
Antimony accumulation in Achillea ageratum, Plantago lanceolata and Silene vulgaris growing in an old Sb-mining area
No full textPreliminary data of a biogeochemical survey concerning antimony transfer from soil to plants in an abandoned Sb-mining area are presented. Achillea ageratum, Plantago lanceolata and Silene vulgaris can strongly accumulate antimony when its extractable fraction in the soil is high (139–793 mg/kg). A. ageratum accumulates in basal leaves (1367 mg/kg) and inflorescences (1105 mg/kg), P. lanceolata in roots (1150 mg/kg) and S. vulgaris in shoots (1164 mg/kg). In these plant species, the efficiency of antimony accumulation decreases when the antimony availability in the soil is high. In A. ageratum and S. vulgaris, the death of the epigeal target part at the end of the growing season contributes to a reduction of the antimony load in the plant. A study to test the use of these species as bioindicators of antimony availability in soil is suggested by our results
Arsenic in soil and vegetation of contaminated areas in southern Tuscany (Italy)
No full textArsenic contents of soils and higher plants were surveyed in two former Sb-mining areas and in an old quarry once used for ochre extraction. Total As in the soils ranged from 5.3 to 2035.3 mg/kg, soluble and extractable As from 0.01 to 8.5 and from 0.04 to 35.8 mg/kg, respectively. The As concentrations in the different fractions of soil were correlated significantly or very significantly. Sixty-four plant species were analyzed. The highest As contents were found in roots and leaves of Mentha aquatica (540 and 216 mg/kg, respectively) and in roots of Phragmites australis (688 mg/kg). In general, the As contents of plants were low, especially in crops and in the most common wild species. In the analyzed species, roots usually showed the highest content followed by leaves and shoots. Arsenic levels in soils and plants were positively correlated, while the ability of the plants to accumulate the element (expressed by their Biological Accumulation Coefficients and Concentration Factors) was independent of the soil As content. Comparison with the literature data, relationships between the As contents in plants and soils, and biogeochemical and environmental aspects of these results are discussed
Relation between some environmental parameters and Santolina etrusca (Lacaita) Marchi et Diamato ocurrence in the stream beds of central Italy
No full textThe relation between the occurrence of Santo lino etrusca, a species endemic of Central Italy, in the stream beds and some environmental parameters (stream bed vegetation, stream bed characteristics, watercourse regime, altitude, exposure, prevailing geology in the neighbourhoad of the station) have been studied by multivariate analysis. The results show that the presence of S. orrisca along streams is closely related to wide stream beds with taarigue and a very permeable stoney-sandy substrate
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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