1,720,980 research outputs found

    Bags with oven dried moss for the active monitoring of airborne trace elements in urban areas

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    To define a harmonized methodology for the use of moss and lichen bags as active monitoring devices of airborne trace elements in urban areas, we evaluated the element accumulation in bags exposed in Naples in different spring weather conditions for 6- and 12-weeks. Three different pre-exposure treatments were applied to moss and lichen materials: water-washing, acid-washing and oven-drying. During the different exposure periods in the Naples urban environment the moss accumulated always higher amounts of elements (except Hg) than lichens and the element accumulation increased during wetter weather and higher PM(10) conditions. The oven pre-treatment did not substantially modify the morphology and element composition of moss and the exposure in bags of this material for 6-weeks was sufficient to detect the pattern of airborne trace elements

    Mapping invasive plants with citizen science. A case study from Trieste (NE Italy)

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    A citizen science initiative was launched in the province of Trieste, aimed at mapping the distribution of Ailanthus altissima, Ambrosia artemisiifolia and Senecio inaequidens. The reliability of citizen data was tested against control data obtained by trained personnel with a stratified random sampling. In spite of the lack of a strict sampling strategy, citizen data were highly correlated with control data. This was mainly due to: 1) the easy identification of the species and 2) the instructions given to citizens for selecting their observation areas and for avoiding duplicate records. The three species tend to be most frequent in disturbed areas; Ailanthus is highly concentrated in the urban area, Senecio is widely distributed but avoids the city centre, with the highest frequency in the industrial area and along the railways, Ambrosia has a similar pattern, but is most frequent in areas with calcareous substrata. The interpretation of the distribution patterns in terms of land use and ecological factors proved to be quite easy when the three species are considered together (higher frequency in disturbed areas), less so when they are considered separately, most probably because of historical and sociological factors, such as incomplete migration into the survey area, and "gentrification effects"

    Influence of exposure sites on trace elemen enrichment in moss-bags and characterization of atmospheric deposition on the biomonitor surface

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    The hypothesis that exposure environment and land use influence element accumulation and particulate size composition in transplants of Hypnum cupressiforme has been tested using moss-bags containing ovendevitalized material. The samples were exposed for three months in ten green sites and ten roadsides in two areas with different land use (A, residential; B, residential/industrial) in the Trieste conurbation (NE Italy). Observations by SEM and EDX-ray microanalysis revealed that particle density was smaller in samples exposed in A than in B, with prevalence of particles containing Al, Ca, Fe and Si, and in good accordance with the element contents measured by acid digestion and ICP-MS. Moss-bags were generally less contaminated in green sites than in roadsides, apparently due to the different enrichment in coarse particles. In both environments, however, the majority of entrapped particles (up to 98.2%) belongs in the inhalable, small size classes (≤PM10). The need for careful selection of the exposure sites during the phase of biomonitoring planning is discussed

    Exploring the relationships between ecology and species traits in cyanolichens: A case study on Italy

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    This work provides an overview of the ecology of all bipartite cyanolichens of Italy, exploring the relationships between ecological factors and species traits. A matrix of 205 species and several ecological descriptors was subjected to multivariate analyses (classification and ordination). Six groups of species with similar ecology were delimited, arranged along a gradient of decreasing aridity and light intensity, from extreme dry habitats on sunny calcareous rocks to very humid and shaded habitats on tree bark. The relationships between ecological species groups and traits were assessed by Principal Component Analysis, carried out on a matrix of ecological species groups and percent occurrences of 11 morpho-biological traits in each group. Along the gradient from arid to humid environments, and from more primeval substrata (rocks, mineral soils) to more recent ones (organic soils, tree bark), morphologically simpler, sexually reproducing cyanolichens are gradually replaced by more complex, often asexual species, which suggests that the current ecology of cyanolichens may retain a phylogenetic signal, indicative of the evolutionary footprint in species adaptation processes

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Natural and pre-treatments induced variability in the chemical composition and morphology of lichens and mosses selected for active monitoring of airborne elements

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    To enhance the reliability of the moss and lichen transplant technique for active biomonitoring of trace metals in urban environments, we evaluated the natural variability in the chemical composition of the (epilithic and epiphytic) moss Hypnum cupressiforme and the epiphytic lichen Pseudevernia furfuracea from two reference areas in NE Italy. Green shoots of epilithic mosses and lobes of epiphytic lichens from larch branches showed rather homogenous composition and were selected for the exposure in nylon bags. As different physico-chemical pretreatments are usually applied to selected cryptogamic material before its exposure, we also evaluated the effects of oven-drying at 120 C for 24 h, washing in 1 N HNO3 solution, and in 0.5% NH4 oxalate solution at 85 C for 15 h on the chemical composition and morphology of water-washed moss shoots and lichen lobes. Pre-treatments remarkably changed the chemical composition of selected materials but not their surface morphology

    Variations on the Author

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    “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

    FlorItaly-the portal to the flora of Italy

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    Digital data concerning the flora of Italy are largely fragmented among different resources hosted on different platforms, and often with different data standards, which are neither connected by a common access point, nor by web services, thus constituting a relevant obstacle to data access and usage. Taxonomic incongruences add a further complication. This paper describes "FlorItaly", an online information system which allows to access and query updated information on the checklist of the flora of Italy, aiming at becoming an aggregator for Italian botanical resources. "FlorItaly" was developed in a collaborative effort by more than 50 taxonomists, with the support of the Italian Botanical Society, and of Project "Dryades" (University of Trieste), to provide a better and reliable organization of botanical knowledge in Italy, as well as a relevant simplification for data retrieval, and a further stimulus towards a more collaborative approach in botanical research
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