1,721,363 research outputs found
Definizione delle situazioni geomorfologiche rilevanti in due diverse AMP secondo la metodologia CARLIT = Definition of relevant geomorphological situations in two different MPAs with CARLIT methodology
Full text linkMacroalgaeis a biological key element for the assessment of theEcological Statusin coastal
waters according to the European Water Framework Directive (2000/60/EC). Here we propose the monitoring of North Sardinia coastal water quality based on CARLIT methodology. A study on the geomorphological factors of two MPAs was made as a first step for the assessment of Reference Conditions fulfils the requirements of the WFD
Escarpments within Mediterranean seagrass posidonia oceanica meadows increase habitat heterogeneity and structural complexity enhancing fish diversity and biomass
Full text linkSeagrass meadows provide important ecosystem services including carbon sequestration, coastal protection from erosion, and sustained biodiversity and fisheries thereby improving the wellbeing and livelihoods of coastal communities. The erosion of millenary deposits of intertwined roots and rhizomes of Posidonia results in the formation of three-dimensional structures named escarpments that constitute a biogenic reef habitat. However, the natural history of seagrass escarpments including their formation processes and their role as habitat for reef fauna and flora remains poorly understood. This research located and characterized Posidonia oceanica escarpments in Menorca (Balearic Islands) and compared structural complexity and fish assemblages among seagrass escarpments, seagrass meadows, rocky substrates and bare sand with emphasis on its role as habitat and shelter for typical rocky fish. Fish abundance and biomass were similar between seagrass escarpments and rocky substrates (P \u3e 0.05), but significantly lower in seagrass meadows (P \u3c 0.001). The large number of caves found along seagrass escarpments provide shelter to fish, including species only associated to rocky substrates. Seagrass meadows form a rather homogenous habitat within their canopy, but the presence of seagrass escarpments enhances habitat heterogeneity and structural complexity along with fish abundance and biomass at the seascape level. This study enhances understanding on the ecological importance of seagrass escarpments
L'aplicació de la fitosociologia als poblaments algals
No full textDuración de 50:19.-- El vídeo está sujeto a una licencia Creative Commons Reconocimiento-Nocomercial-CompartirIgual 3.0 España.Segunda ponencia dentro del homenaje a Ramón Margalef celebrado en el Instituto Botánico de Barcelona el 13 de mayo de 2014. Forma parte del ciclo de conferencias "Ramon Margalef (1919-2004): 10 anys recordant al mestre".Peer reviewe
Mass flowering and unprecedented extended pseudovivipary in seagrass (Posidonia oceanica) after a Marine Heat Wave
No full textSeagrasses are marine flowering plants that create critical coastal ecosystems and are threatened by warming. Clonal expansion is generally the dominant strategy for meadow recovery, while sexual reproduction strongly differs among species (e.g., monoecious and diecious species, some creating seed banks, viviparous seedlings). In 2022, the Western Mediterranean underwent unprecedented warming, and, associated with it, we observed flowering (100 %) across 11 Posidonia oceanica meadows in Mallorca, Balearic Islands. Furthermore, 64 % of the sites also exhibited pseudovivipary, an extremely rare phenomenon in angiosperms whereby plantlets replace sexual reproductive structures, producing clones of the maternal plant. Our results support the notion that P. oceanica flowering and pseudovivipary (genetically confirmed) are triggered by warming, never before being pseudovivipary reported across multiple sites in a marine plant. Considering the negative impacts that warming can have on seagrasses, existence of widespread pseudovivipary is a critical aspect to consider for understanding mechanisms of resilience in seagrasses.Funding was provided to F.T. by the Government of the Balearic Islands (CAIB), within the research program “Ajudes a Projectes Biodiversitat Emmarcats dins els Plans Complementaris” through the project “Incorporación de nuevas tecnologías en la caracterización del estado de conservación de los bosques submarinos de Baleares y su contribución a servicios ecosistémicos (BIO022 PRTR BIODIV ConBoSer-Bio)”. IMEDEA is an accredited “Maria de Maeztu Excellence Unit” (Grant CEX2021-001198, funded by MICIU/AEI/10.13039/501100011033). The work by GP was partially supported by the European Union - NextGenerationEU (National Recovery and Resilience Plan (NRRP), Mission 4 Component 2 Investment 1.4, Project Code: CN00000033) and by internal funds of the Stazione Zoologica Anton Dohrn, Naples, Italy. DHM would like to acknowledge Erasmus+ grant awarded by the Flemish Higher Education Council (VLUHR), on behalf of Ghent University. XR would like to acknowledge CAIB, FPI Fellowship of the ADMINISTRACIÓ DE LA COMUNITAT AUTÒNOMA CONSELLERIA DE FONS EUROPEUS, UNIVERSITAT I CULTURA, Resolució del conseller de Fons Europeus, Universitat i Cultura. GH would like to acknowledge a postdoctoral ‘Vicenç Mut’ contract co-funded by the Council of European Funds, University, and Culture of the Government of the Balearic Islands.With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001198).Peer reviewe
Torn de preguntes dins de l'homenatge a Ramon Margalef a l'Institut Botànic de Barcelona
No full textDuración de 24:48.-- El vídeo está sujeto a una licencia Creative Commons Reconocimiento-Nocomercial-CompartirIgual 3.0 España.Turno de preguntas dentro del homenaje a Ramon Margalef celebrado en el Instituto Botánico de Barcelona el 13 de mayo de 2014. Forma parte del ciclo de conferencias "Ramon Margalef (1919-2004): 10 anys recordant al mestre".Peer reviewe
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
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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