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Characterization of the population of Diadema antillarum Philippi in the West of Santa María Key
No full textEn 1983 y 1984, las poblaciones de
Diadema antillarum
sufrieron una mortalidad masiva en
todo el Caribe; la cual redujo las densidades de entre
93 y 98%. Este evento indujo cambios
en la estructura y funcionamiento de las comunidades coralinas; provocando un cambio de
fase, de arrecifes dominado por corales pétreos a arrecifes dominados por macroalgas. En
Cuba sólo hay un registro sobre el estado
de sus poblaciones antes del evento de mortalidad
y los estudios recientes se concentran en el occidente del país. Este estudio caracteriza la
población de la especie al Oeste de cayo Santa María. Para esto se realizaron un total de
103 transectos de 20 m
2
durante tres muestreos, entre junio de 2016 y junio de 2018. Se
obtuvo un total de 432 registros de
D. antillarum,
de los cuales
el 97,16% se encontraba
protegido y el 2,84% expuesto. La densidad media sufrió una disminución durante los tres
años, provoca
do por una disminución significativa de la densidad de individuos adultos. Esto
se reflejó en una disminución del tamaño y la cantidad de grupos. Por lo que, durante el año
2016 el patrón de distribución espacial fue fuertemente agregado y este cambió haci
a un
patrón regular. La estructura etaria de la población también cambió a partir de disminución
de la densidad, de un predominio de individuos adultos a un predominio de juveniles.
Además, se ratifica a
D. antillarum
como el herbívoro principal, dado que
cuando la densidad
del erizo fue mayor a 0,5 ind/m
2
la cobertura de macroalgas no superaba el 40%.In 1983 and 1984, a massive mortality of
Diadema
antillarum
populations occurred i
n the
Caribbean; the densities were depleted at 93 and 98 %. This event induced changes in the
structure and functioning of the coral reefs communities; by causing a phase shift, from reefs
dominated by stony coral to macroalgae dominated. In Cuba there is
only a report of
population status before the event and recent studies are concentrated in the western half of
the country. This study characterizes the population of the species westwards of Santa María
key. For this, a total of 103 transects were carrie
d out, of 20 m
2
each, during three years,
between June 2016 and June 2018. A total of 432 records of
D. antillarum
were obtain, of
which 97.16% found protected and 2.84% exposed. The population density suffered a
decrease during the three years, caused by
significant reduction of the density of adult
individuals. This it was reflected in a decrease of the size and the quantity of groups. During
the year 2016 the pattern of spatial distribution was highly aggregated and changed towards
a regular pattern. Th
e age structure of the population also changed along the density
diminution, from a predominance of adult individuals to a predominance of juvenile.
Moreover,
D. antillarum
is confirmed as the main herbivore, because when the density of the
species was ove
r to 0.5 ind/m
2
the cover of macroalgae did not surpass 40%.Facultad de Ciencias Agropecuarias.Departamento de Biologíanon-publishe
Composición, abundancia y distribución de los reclutas y juveniles de corales pétreos al oeste de cayo Santa María, Villa Clara, Cuba
No full textEl reclutamiento de organismos en los ecosistemas marinos constituye uno de los
procesos clave en su mantenimiento, permitiendo la renovación de las distintas
poblaciones que habitan en un lugar determinado. Por esta razón se aborda el estudio de los reclutas de una comunidad coralina somera, al oeste de Punta Matamoros, cayo Santa María, Villa Clara, Cuba. Los muestreos se tomaron mediante el empleo de cuadrantes de un metro cuadrado en la comunidad coralina somera al norte del Guanal. Se aprecia que las especies que más aportan al reclutamiento resultaron ser Porites astreoides y Porites porites con el 62 % del total. La abundancia de reclutas en el 2011 no difiere de la reportada para el 2010; las colonias más abundantes son las de las clases de dos y tres centímetros con el 77 % del total. Los patrones de distribución encontrados se corresponden con dispersiones al azar y regulares. En la zona predominaron especies incubadoras sobre las desovadoras y existe una relación alta con las especies de adultos representada por un 66,73 %. La dominancia de especies reclutas resistentes a la sedimentación, temperatura, cambios de salinidad e hidrodinámica alta sugiere que la zona puede estar sometida a estos factores estresantes.The recruitment of organisms in the marine ecosystems constitutes one of the key
processes in its maintenance, allowing the renovation of the distinct populations that
inhabit a given place. For these reason studies of the recruitment of a superficial coral
community are realized, to the west of Tip Matamoros, cayo Santa María, Villa Clara,
Cuba. The samples were taken through the use of quadrant of one square meter in the
superficial coral community to the north of Guanal. It is observed that the species that most contribute to the recruitment turned out to be Porites astreoides and Porites porites with a 62 % of the total. The abundance of the recruits in 2011 does not differ from the ones reported for 2010; the most abundant colonies are the ones of the two and three centimeters classes with 77 % of the total. The distribution patrons that were found correspond to the random and regular dispersions. In the zone predominated brooding species over the broadcaster and there exists a high relation with the adult species represented by 66, 73 %. The dominance of the recruited species resistant to
sedimentation, temperature, changes in salinity and high hydrodynamics suggest that the zone could be submitted to these stress factors.Facultad de Ciencias Agropecuarias. Departamento de Biologíanon-publishe
Estructura y salud de la comunidad coralina de Punta Madruguilla, Cayo Santa María, Villa Clara. Cuba.
No full textEl estudio pretende caracterizar la comunidad coralina del arrecife frontal de Punta Madruguilla en cayo Santa María, Villa Clara. Para esto se realizaron un total de tres muestreos; mayo de 2011, septiembre de 2011 y mayo de 2012, mediante buceo autónomo. En cada uno se analizaron todas las colonias dentro de 20 marcos cuadrados ubicados cada dos metros en 4 transectos. Se registraron un total de 875 colonias de 28 especies, la más abundante fue Agaricia agaricites. La cobertura de coral vivo promedió 50,2% y la especie que más aportó a la misma fue Agaricia tenuifolia. En septiembre de 2011 el valor del blanqueamiento fue del 65%. Las especies más afectadas fueron A. agaricites, Eusmilia fastigiata y A. tenuifolia. La enfermedad que más perjudicó al arrecife fue la plaga blanca y la mortalidad fue mayor en 2011. La mortalidad antigua fue más abundante que la reciente pero menos variable. Las cianobacterias fueron más abundantes en septiembre con un promedio de 50%, mientras que en 2012 disminuyeron al 5%. Por todo lo antes mencionado se consensó que el arrecife posee un alto grado de conservación, alta diversidad de especies, abundancia y cobertura de coral vivo, además de reflejar un ambiente estableFacultad de Ciencias Agropecuarias. Departamento de Biologíanon-publishe
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
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
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
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