1,720,973 research outputs found
Systematic Conservation Planning in a Mediterranean island context: The example of Cyprus
Full text linkCyprus’ biodiversity is under increasing pressure due to anthropogenic activities. TheNatura 2000 (N2K) sites under the Habitats Directive cover 10.4% of its island's land surface while designation has been hindered by a complex political situation. We used a comprehensive dataset of Red Data Book (RDB) plants for the island and applied systematic conservation planning (SCP) to, (i) assess whether plant conservation features are adequately represented in the current Sites of Community Importance (SCIs) of the N2K, (ii) evaluate the effectiveness of the protected areas designated for plants by assessing the solutions of SCP against five widely used criteria and iii) suggest alternative protected areas configurations following basic principles of SCP. We run two scenarios in Marxan, using different cost surface and Boundary Length Modifier (BLM) parameters, one for all Annex II plant species and one for RDB plants. Targets were set for all conservation features (CFs) on the basis of their endangered status and endemism. The total area required to satisfy the targets ranged from 2.23% to 5.46% of the island's area. Solutions with uniform cost achieve targets for the lowest cost but have the smallest overlap with the existing N2K (52.5–60.3%). Solutions with variable cost achieve significantly higher overlap with N2K (72.9–75.9%). The use of BLM reduces fragmentation and increases the number of irreplaceable PUs in both scenarios. The overlap of irreplaceable PUs with Critically Endangered species is high. Results corroborate that state-owned land provide protection to most threatened species, but there is a need for additional protected areas. Our findings provide a basis for improving the N2K network design in Cyprus to achieve biodiversity targets set for 2030, such as the increase of the land area providing legal protection to threatened plant species by considering our priority list of species and sites for future designation
Human impacts on Quercus suber habitats in Sardinia: past and present
No full textQuercus suber L. is a species confined to the centre and western Mediterranean basin. On the island of Sardinia its distribution is limited mainly by soils. Apart from its economic significance to local communities, cork oak habitats are recognised as having both cultural and biodiversity value at a European level. Although traditionally associated with human activities these habitats are today under increasing threat. Among the problems that affect cork oak habitats on the island are soil erosion and loss of organic matter due to ploughing and seeding for pasture. Stock numbers have increased while grazing cattle have been replaced by sheep and are proven to be particularly damaging especially to cork oak regeneration. Although the species is a passive pyrophyte, frequent fires render the trees susceptible to fungal and defoliator attacks and destroy the understory leading to soil degradation and erosion. This paper provides a review of these threats and explores their link to the changes resulting from abandonment of traditional farming methods and different management systems used in Sardinia
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
Landscape Typology in the Mediterranean context: A tool for habitat restoration
No full textDespite the wide use of Landscape Character Assessment (LCA) as a tool for landscape planning in NW Europe, there are few examples
of its application in the Mediterranean. This paper reports on the results from the development of a typology for LCA in a study area of northern Sardinia, Italy to provide a spatial framework for the analysis of current patterns of cork oak distribution and future restoration of
this habitat. Landscape units were derived from a visual interpretation of map data stored within a GIS describing the physical and cultural characteristics of the study area. The units were subsequently grouped into Landscape Types according to the similarity of shared attributes 36 using Two Way Indicator Species Analysis (TWINSPAN). The preliminary results showed that the methodology classified distinct Land- 37 scape Types but, based on field observations, there is a need for further refinement of the classification. The distribution and properties of
two main cork oak habitats types was examined within the identified Landscape Types namely woodlands and wood pastures using Patch Analyst. The results show very clearly a correspondence between the distribution of cork oak pastures and cork oak woodland and landscape types. This forms the basis of the development of strategies for the maintenance, restoration and recreation of these habitat types within the study area, ultimately for the whole island of Sardinia. Future work is required to improve the landscape characterisation , particularly with respect to cultural factors, and to determine the validity of the landscape spatial framework for the analysis of cork oak distribution as part of a programme of habitat restoration and re-creation
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
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