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Conservation challenges in urban seascapes: promoting the growth of threatened species on coastal infrastructures
No full textSummary
1. With nearly two-thirds of the human population concentrated along coastlines, coastal
development and urbanized seascapes are inevitable. Proliferation of coastal and marine
infrastructures, such as breakwaters, ports, seawalls and offshore installations, is associated
with loss of natural habitats. This calls for new strategies aimed at elevating the ecological
and biological value of coastal infrastructures, while minimizing their ecological footprint.
2. We explored the feasibility of using coastal defence structures as a scaffold for the conservation
of threatened marine species. We experimented with fucoids, canopy-forming algae on
Mediterranean coasts, in the light of their declared conservation priority. We transplanted
juveniles of Cystoseira barbata to a number of breakwaters and natural sites along the Adriatic
Sea (Italy) and tested which factors could facilitate or inhibit its successful establishment.
3. Survival of transplanted C. barbata was greater at most artificial and natural sites examined
compared to the native sites where severe habitat loss was ongoing. Survival was greater
at landward compared to seaward positions on the infrastructure, while no relevant effects of
substratum characteristics (horizontal vs. vertical orientation, variable composition and
increasing complexity) were observed. Lack of surrounding adult fronds did not impair the
survival or growth of the transplants, suggesting a high transplantation potential also on
novel infrastructures.
4. Success of transplantation in areas remote from the source population was limited by biotic
disturbance, which was more intense on coastal infrastructures in sedimentary environments
compared to natural rocky sites.
5. Synthesis and applications. Coastal and marine infrastructures can be harnessed to enhance
desired species (such as threatened canopy-forming algae). A comprehensive understanding of
the ecological functioning of these urban seascapes compared to natural habitats is required
to minimize detrimental impacts, or potentially increase the ecological value, of coastal structures
and efficiently incorporate such strategies into management and conservation actions.
We investigated the influence of habitat type (including natural and artificial), surface complexity,
herbivore exclusion, proximity to established populations and orientation on the
transplantation success of threatened algae
Blue is the New Green – Harnessing Urban Coastal Infrastructure for Ecological Enhancement
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Sympodium arbusculum Benayahu & Ekins & Mcfadden 2021, sp. n.
No full textSympodium arbusculum sp. n. Figs. 1, 2, 3A Material. Madagascar. Holotype: SMNHTAU_ Co _36017, Ankaréa (12°50.054’S, 48°34.563.3’E), 6–9 m, 29 November 2012, coll. Y. Benayahu; Paratypes: SMNHTAU_ Co 38226, five colonies, same details as the holotype; SMNHTAU_ Co _36015, same details; Tanzania, SMNHTAU_ Co _32919, Shundo (4°52’53”S, 39°18’10”E), 0–25 m, 10 December 2004, coll. Y. Benayahu; Kenya. SMNHTAU_ Co _31143, off Mombasa, Turning Buoy, 10 m, 16 February 2001, coll. Y. Benayahu & S. Perkol-Finkel; SMNHTAU_ Co _31153, same details; SMNHTAU_ Co _31163, off Mombasa, Simon’s Corner, 20–26 m, 20 February 2001, coll. Y. Benayahu & S. Perkol-Finkel; Kenya, SMNHTAU_ Co _31173, off Mombasa, Shelly Beach, 10–12 m, 20 February 2001, coll. Y. Benayahu & S. Perkol-Finkel; SMNHTAU_ Co _31495, off Likoni, Shelly Reef (4°06.4’S, 39°41’S), 19 m, 9 March 2002, coll. Y. Benayahu; SMNHTAU_ Co _31512, off Likoni, Wall (4°06.4’S, 39°42’E), 15–27 m, 2 February 2002, coll. Y. Benayahu; SMNHTAU_ Co _31590, off Likoni, Shelly Reef (4°06.4’S, 39°41’E), 19 m, 9 March 2002, coll. Y. Benayahu. Description. The holotype is an encrusting colony attached by a membrane to calcareous fragments, and measures 1.9 x 1.5 cm (Fig. 1A). Its soft basal membrane is thin, <1 mm thick. Clusters of non-retractile polyps bud off at different levels, occasionally dichotomously, to form small branched groups of polyps (Fig. 1A). Occasionally, individual polyps arise from the membrane between the clustered polyps. The polyps that are the most expanded are up to 4 mm long and the tentacles are up to 1 mm long. The poor preservation state of the sample prevents a precise pinnule count, but it is estimated to be a single row with up to 10 slender and pointed pinnules on either side of the tentacle. The sclerites of the holotype are ellipsoid platelets, abundant throughout the colony, 0.010 –0.011 x 0.015 –0.017 mm in diameter (Fig. 2A). They are composed of tightly packed calcite rods whose tips provide a uniform granular appearance to the sclerite surface (Fig. 2B) Color. The ethanol-preserved colony is light cream.. Etymology. The species’ name is derived from the Latin ‘arbuscula’, bush, referring to the clustered arrangement of polyps. Variation. The paratype SMNHTAU_Co_38226 comprises four colonies that vary in size: the smallest colony measures 1.0 x 0.5 cm and the largest one 3.5 x 1.5 cm (Fig. 1B: one of the paratypes). Groups of polyps comprising these paratypes range in number of polyps from 4 to 18, and are up to 20 mm long from the basal membrane to the tip of the uppermost polyp. The paratype SMNHTAU_Co_36015 comprises eight colonies or fragments that resemble the holotype, except in size. The dichotomous arrangement of the polyps is visible (Fig. 1C, D). Both the dimensions of the paratypes’ sclerites (Fig. 2C) and their surface microstructure (Fig. 2D) correspond to those of the holotype (Fig. 2A, B). Remarks. The morphology of the colonies, and in particular the arrangement of the non-retractile polyps in clusters, is considered to be diagnostic of the species. The holotype was sequenced and subsequently assigned to MOTU38 (McFadden et al. 2019). Living features. The live brownish colonies feature clusters of expanded polyps (Fig. 3A). Distribution. Kenya, Madagascar, Tanzania.Published as part of Benayahu, Yehuda, Ekins, Merrick & Mcfadden, Catherine S., 2021, Overview of the genus Sympodium Ehrenberg, 1834 (Octocorallia, Alcyonacea, Xeniidae), with the description of new species, revealing regional endemism, pp. 324-350 in Zootaxa 5072 (4) on pages 328-331, DOI: 10.11646/zootaxa.5072.4.2, http://zenodo.org/record/574886
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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