1,720,959 research outputs found
Marine and bio-resources in the Indian Ocean Rim Association
No full textThis chapter explores the importance of the marine eco-system and bio-resources for integration of the oceans into mainstream Indian Ocean Rim Association member countries. It addresses the need to strike a balance between development linked to the Blue economy and sustainable use of bio-resources, which includes conservation of marine biodiversity, sustainable fishing, eco-tourism and the protection of ocean ecosystems from pollution the future. Particular attention is paid to the human impact on bio-resources, the related question of sea ethic, and how the utilization of marine resources can be regulated for the benefit of all stakeholders. The chapter also examines the impact of climate change on bio-resources within IORA.
Fish Biodiversity: Local Studies as Basis for Global Inferences,
No full textThis paper attempts to update information on scientific and recommended English common names and the distribution of fish species of Kenya occurring in the Eastern Arm of the Rift Valley drainage system. At least 20 fish families from 35 genera and 66 species occur in the drainage system, with Lake Turkana catchment having the richest species diversity at 50 (76%). Five (8 %) fish species have been introduced into the drainage, mostly for commercial purposes and sports, viz: in Lake Naivasha, largemouth bass, Micropterus salmoides; blue spotted tilapia, Oreochromis leucostictus; Athi River tilapia, Oreochromis spilurus niger; Zillii’s tilapia, Tilapia zillii; and in Lake Nakuru, a species tolerant to high salinities, the Lake Magadi tilapia, Oreochromis alcalicus grahami. These introductions may have caused, e.g., the extinction of the Naivasha lampeye, Aplocheilichthys sp. from Lake Naivasha. Most fishes occurring in the drainage are at times capable of living in both lacustrine as well as riverine conditions, except three (5 %), which tend to be entirely riverine. Two minnows, (i) Loveridge’s barb, Barbus loveridgii occurs in Amala River, an affluent of Lake Baringo; and (ii) Newmayer’s barb, Barbus neumayeri is spread out in several rivers, i.e., Suam in Mount Elgon, Subukia in the Lake Bogoria catchment, Seya in Isiolo district, Sinet near Loitoktok, Waseges in the Lake Bogoria catchment, and Kerio affluent in the Lake Turkana catchment. One cichlid, the Suguta tilapia, Oreochromis niloticus sugutae occurs in Suguta River and its tributaries. The exact distribution in northern Kenya of the Ethiopian barb, Barbus intermedius intermedius is lacking. Notes are included for selected fish species to clarify and to correct erroneous information occurring in the literature.Publishe
Updating names, distribution and ecology of riverine fish of Kenya in the Athi-Galana-Sabaki river drainage system
Get PDFFew studies of the riverine fish of the Athi-Galana-Sabaki river drainage area in Kenya have been carried out since the last comprehensive surveys of the 1950s and early 1960s. This paper presents updated information on scientific and recommended common names, distribution and ecology of selected fish species of this catchment. At least 28 riverine fish families consisting of 46 genera and 62 species occur in the drainage system, of which, 39 species are strictly freshwater (4 introduced) while 23 species are of marine origin. Five unique behavioural categories of the riverine fish of the drainage system are discussed. The four most speciated riverine fish in the system belong to the families Cyprinidae (14 species), Cichlidae (6 species), and Mormyridae and Gobiidae (4 species each). Thirty fish species occur in areas below the River Tsavo-Athi confluence, 18 fish species above the confluence, while 12 fish species occupy the entire drainage system. One cichlid fish, Oreochromis spilurus spilurus (Gunther, 1894), only occurs in the Tsavo river, while the occurrence in the entire system of one snoutfish species, Mormyprops anguilloides (Linnaeus, 1758) is uncertain. The use of information from this study is recommended when carrying out further studies of fish from the Athi-Galana-Sabaki river drainage
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
Updating names, distribution and ecology of riverine fish of Kenya in the Athi-Galana-Sabaki river drainage system
No full textFew studies of the riverine fish of the Athi-Galana-Sabaki river drainage area in Kenya have been carried out since the last comprehensive surveys of the 1950s and early 1960s. This paper presents updated information on scientific and recommended common names, distribution and ecology of selected fish species of this catchment. At least 28 riverine fish families consisting of 46 genera and 62 species occur in the drainage system, of which, 39 species are strictly freshwater (4 introduced) while 23 species are of marine origin. Five unique behavioural categories of the riverine fish of the drainage system are discussed. The four most speciated riverine fish in the system belong to the families Cyprinidae (14 species), Cichlidae (6 species), and Mormyridae and Gobiidae (4 species each). Thirty fish species occur in areas below the River Tsavo-Athi confluence, 18 fish species above the confluence, while 12 fish species occupy the entire drainage system. One cichlid fish, Oreochromis spilurus spilurus (Gunther, 1894), only occurs in the Tsavo river, while the occurrence in the entire system of one snoutfish species, Mormyprops anguilloides (Linnaeus, 1758) is uncertain. The use of information from this study is recommended when carrying out further studies of fish from the Athi-Galana-Sabaki river drainage
A Photographic Guide to Freshwater Fishes of Kenya.
No full textThis book is dedicated to the original authorities of freshwater fishes of Kenya, who made tireless efforts to describe and name fish species, before, during and post exploration times
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
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