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Population Dynamics of Genus Keratella in Dal Lake, Kashmir
Get PDFRotifera as a groups as well as a particular rotifer species are able to
inhabit a variety of environments and are known to be mostly typically littoral
forms. Rotifers are sensitive to changes in water quality through eutrophication
process and play an important role in trophic dynamics of lake ecosystems. The
community structure of rotifers within shallow and macrophyte dominated
lakes is affected by a number of environmental factors. The valley of Kashmir
is endowed with a unique geographical position. The valley is famous for its
lakes, crystal clear tarns, mountains, snow and spring fed meadows and alpine
forests. Kashmir is unique in India in having numerous lakes which grade from
oligotrophic (Marsar, Vishensar, Sheshnag, Kishensar, Alpather, Kounsarnag
etc), mesotrophic (Mansbal, Nilnag etc) and eutrophic (Dal, Anchar etc).The
Dal lake is the second largest lake of Kashmir covering an area of about 11.56
sq km. The lake is surrounded by Zabarwan hills on three sides. It is a shallow
open drainage type water body divided into five basins- Hazratbal basin,
Gagribal basin, Nishat basin, Nigeen basin and Brarinambal basin. For the
present study five sites were selected in different basin of the lake and each site
represents ecologicaly different habitats in the lake. Site 1 was located near
Telbal Nallah, Site 2 in Hazratbal basin, Site 3 in Nigeen basin, Site 4 near
Centaur hotel in Nishat basin and Site 5 in Brarinambal basin. Water samples
were collected for different physical, chemical and biological parameters on
monthly basis form Jan. 2011 to Dec. 2011. Standard methods proposed by
Welch (1984), APHA (1995), Mackereth et al. (1978) were employed for
determination of physico-chemical parameters. Indentification of different
zooplankton species was done with the help of standard taxonomic works by
Edmondson (1959) and Pennak (1978).The Dal lake is in a state of stress and
as a result ecological conditions have undergone tremendous changes. The
present study was undertaken to study the population dynamics of rotifera with
special reference to genus Keratella, other zooplankton associations and physic-chemical environment. Keratella is an important genus of eurotatorian
rotifers. Different species of genus Keratella can be distinguished on the basis
of spination and sculpture of dorsal plate. In the present study only two species
of Keratella were recorded i.e. keratella cochlearis and Keratella quadrata.
Keratella cochlearis was the dominant one among two species.
Water temperature in the lake fluctuated from 3.5oC to 26oC and a close
relationship was recorded between water temperature and air temperature.
Transparency fluctuated form site to site and least transparency was found in
Brarinambal. The lake was alkaline throughout the year as pH always remained
above 7.0. Conductivity value ranged from 163μs/cm to 810μs/cm. Dissolved
oxygen ranged from 0.8mg/l to 9.8m/l. Lower values were recorded during
summer and higher during winter. Chloride concentration ranged from
11.9mg/l to 71.3mg/l. Total alkalinity ranged from 94.8mg/l to 360.9mg/l. No
definite trend was recorded in ammonical nitrogen concentration throughout
study period. The concentration of nitrate ranged from 72.1mg/l to 925.2mg/l.
Nitrite nitrogen was present in low concentration. Increase in total phosphorous
concentration indicates that lake is eutropic in nature and Brarinambal basin is
in its advanced hypereutrophic stage. During present study a total of 42 other
species of zooplankton were recorded of which 20 belonged to rotifera, 18 to
cladocera and 4 to copepoda. On the basis of physico-chemical and biological
features Brarinambal basin stands quite different from other basins in most of
its limnolgical features
Ecological studies of zooplankton of Dal Lake Kashmir.
No full textThe basic aim of present work is to study the species composition and population dynamics of zooplankton and to elucidate some of the relationships between tropical state and zooplankton in Dal Lake of Kashmir. The study provides introduction, review of literature, provides the materials and methods adopted for the study. The study presents results under the three headings:
(1)Physico-chemical factors (2) Phytoplankton (3) Zooplankton and (4) Similarity index. The results are discussed separately, besides giving summary and conclusion. The tables and figures are appended at the end
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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