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Life history, population dynamics and conservation of underwater Mediterranean forests: insights from the long-lived alga Cystoseira zosteroides = Història de vida, ecologia de poblacions i conservació dels boscos submergits del Mediterrani: el cas de l'alga longeva Cystoseira zosteroides
No full text[eng] Life history theory and population ecology have been especially neglectful of marine species, with most ecological principles developed from studies based on terrestrial species. This is especially true for macroalgae species, for which population dynamics and life history studies are still scarce. Given their fundamental role as habitat-forming species and primary producers in temperate seas worldwide, understanding the dynamics of macroalgae populations is fundamental, not only for their own conservation but also for their associated biodiversity and marine coastal ecosystems functioning.
Therefore, the present dissertation aims to unravel some of the processes and mechanisms that shape the population dynamics of the deep-water, long-lived and habitat-forming macroalga, Cystoseira zosteroides. With this information, we aim to bolster our ability to predict the future of this species in a globally impacted world, as well as to develop management tools to improve their conservation status. Overall, we aim to improve our current comprehension about the population dynamics and life history of macroalgae.
The results obtained from our monitored populations show that C. zosteroides have slow population dynamics. By using comparative analyses, we observed contrasting life history strategies among macroalgae species. While other intertidal fucoid and kelp populations highly depend on reproductive processes and the growth of organisms, natural and undisturbed C. zosteroides populations are maintained by the high survival and long lifespan of adult individuals. We also demonstrated that the dispersal ability of brown macroalgae is very limited compared to other taxa, with kelps showing higher dispersal potential than fucoids.
Our findings showed that disturbances highly influence C. zosteroides population dynamics. After an extreme storm and the impact of a ghost fishing net, their populations displayed a high increase in recruitment rates, suggesting a negative density-dependence effect of adults on early stages. We observed that in recruitment plates located inside well-developed adult canopies post-settlement survival is lower than outside the adult canopy. This evidence that adult C. zosteroides individuals establish a ceiling for the development of recruits. Thus, density-dependence plays a key role regulating C. zosteroides population dynamics, triggering their recovery after major disturbances. In contrast to natural populations, after major mortality events, their recovery and dynamics highly depend on the reproductive process. This is particularly worrying given the limited effective dispersal of this species.
Finally, despite the high ability of C. zosteroides to compensate morality pulses through density-dependence, their recovery can take decades, rendering their populations more vulnerable. Although isolated mortality events can be compensated, our demographic simulations showed that the combined effect of physical disturbances, compromise the viability of C. zosteroides populations. Furthermore, we demonstrated that warming has a
high impact on early life stages of this species. Decreased early survival and settlement rates due to rising temperatures delay the recovery ability of C. zosteroides and increase the vulnerability of their populations.
Overall, our findings do not only contribute to better comprehend macroalgae population dynamics, but also provide new insights for their effective management. With this dissertation we evidence the key role of population ecology and life history into understanding the dynamics of species, stressing how these disciplines may help us to better comprehend the future of coastal marine ecosystems.[cat] La teoria sobre les històries de vida i l’ecologia de poblacions desenvolupen principis ecològics basats principalment en estudis realitzats en espècies terrestres, sovint sense tenir en compte les espècies marines. A través d’aquesta tesi preteníem descriure alguns dels processos i mecanismes que configuren la dinàmica poblacional de Cystoseira zosteroides, una macroalga longeva i formadora d’hàbitat, que habita en aigües profundes del Mediterrani Nord- Occidental. En un context més ampli, també es pretén augmentar la nostra comprensió actual sobre la dinàmica poblacional i la història de vida de les macroalgues. Els resultats obtinguts mostren que C. zosteroides presenta una dinàmica poblacional molt lenta. Mentre que altres poblacions de Fucals i de Kelps d’hàbitats de poca profunditat depenen principalment de processos reproductius i del creixement dels organismes, les poblacions naturals i no pertorbades de C. zosteroides es mantenen gràcies a l’elevada supervivència i la llarga esperança de vida dels individus adults. També demostrem que la capacitat de dispersió de les macroalgues brunes és molt limitada en comparació amb altres taxons, tot i que els Kelps presenten un major potencial de dispersió que les Fucals. Els nostres resultats també demostren que la denso-dependència juga un paper clau regulant la dinàmica poblacional de
C. zosteroides, ja que pot impulsar la seva recuperació després de grans pertorbacions. A diferència de les poblacions no alterades, després de grans esdeveniments de mortalitat, la recuperació i dinàmica de les poblacions de C. zosteroides depèn molt dels processos reproductius. Això és especialment preocupant donada la limitada dispersió efectiva d’aquesta espècie. No obstant, tot i que els esdeveniments de mortalitat aïllats es poden compensar amb polsos de reclutament, les nostres simulacions demogràfiques demostren que l’efecte combinat dels pertorbacions físiques, com les tempestes i les xarxes de pesca abandonades, comprometen la viabilitat de les poblacions de C. zosteroides. A més, hem demostrat que l’escalfament té un gran impacte en les primeres etapes de vida d’aquesta espècie, fet que retarda la capacitat de recuperació de C. zosteroides i augmenta la seva vulnerabilitat a altres pertorbacions. En general, els nostres resultats no només contribueixen a comprendre millor la dinàmica poblacional de les macroalgues, sinó que també proporcionen noves idees per a la seva gestió eficaç. Amb aquesta tesi, es demostra el paper clau de l’ecologia de poblacions i la història de la vida en la comprensió de la dinàmica de les espècies i destaca com aquestes disciplines poden ajudar-nos a entendre millor el futur dels ecosistemes marins costaners
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
No full text“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
No full textWe 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
No full textWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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