1,720,982 research outputs found

    The contribution of plant sociology to the ecosystem service approach in urban and peri-urban areas: Evidences from a Mediterranean metropolis case study (Rome, Italy)

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    In this paper, we promote the use of vegetation and land cover data as biodiversity indicators of pressure, state and impact for ecosystem goods and services in urban and periurban landscapes. In the case study of the Municipality of Rome, a Mediterranean metropolis with a long history of care for biodiversity conservation and sustainable development, recent landscape researches have been addressed towards typification of plant communities, modelling of vegetation series, ecological land classification, design of land ecological network and analysis of land cover change. The results of these investigations have been employed for the identification and ecological evaluation of some locally relevant ecosystem services - such as habitat provision, conservation of species diversity, urban climate regulation, and educational values - and provide experimental evidence of the bioindication potential of plant communities and vegetation series

    A first revision of the Italian Ecoregion map

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    According to advances in phytogeographic knowledge, a revision of boundaries for the Italian Ecoregions have been made. Main changes relate to the southern and eastern limits between Temperate and Mediterranean Divisions. The revision triggered a comprehensive update of Ecoregions for an improved support to biodiversity and sustainable management initiatives

    A landscape analysis of land cover change in the Municipality of Rome (Italy): Spatio-temporal characteristics and ecological implications of land cover transitions from 1954 to 2001

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    This paper presents a landscape analysis of land cover change in the Municipality of Rome from 1954 to 2001. The overall objective of the analysis is to characterise the temporal and spatial pattern of change and to explore its potential ecological impact. We used three original land cover layers and a set of landscape metrics to describe variations in composition and pattern of land cover types. We then built change trajectories for patches derived from the spatial intersection of land cover data. These trajectories were ecologically assessed using expert judgement and indicators of naturalness such as deviation from potential natural vegetation. The results revealed that approximately 62% of the study area maintained the same land cover type from 1954 to 2001 as a result of composition continuity at the patch level. Urbanisation was by far the most important change process and the main cause of fragmentation of agricultural land and loss of coastal habitats, which imply possible negative effects for biodiversity and ecological processes. However, the star-shaped pattern of urbanisation favoured natural vegetation dynamics, marked persistence of woodlands, and significant stability of agricultural land in peripheral areas, with positive effects in terms of ecological connectivity and vegetation recovery potential. Despite the general nature of land cover data, the spatially explicit ecological assessment of transitions provides a reference layer that can effectively address territorial policies towards urban sustainability and that helps stratification for areas requiring direct investigation of impacts

    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

    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

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We 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
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