Joselet Mathew; Dr.Kulasekarapandian, S(Cochin University Of Science And Technology, November 6, 1990)
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Abstract:
This thesis deals with the population characteristics of Artemia
and the effect of different environmental parameters on the different
stages of Artemia in a salina at Tuticorin, south east coast of India.
The present investigation was carried out from 1985 to I987.
The study was initiated by undertaking a survey to find out suitable
Artemia habitats along the south east coast of India and a perennial
salina with an area of 0.25 ha was selected at Karapad (Tuticorin). Weekly
samplings were made for two full calender years (1986-87) to collect
the different stages of Artemia population as well as the different
environmental parameters. The thesis comprises of the following sections: Introduction, materials and methods, systematics, biology and distribution of Artemia, results and discussion, summary and bibliography. The section on results
and discussion gives the characteristics of Artemia population in the
salina, the seasonal variations of different environmental parameters
in the salina and their effects on different stages of Artemia population.
Description of an experiment conducted to show the sudden changes of
salinity on different stages of Artemia is also given as a separate
section.
Description:
Centre Of Advanced Studies In Mariculture,Cochin University Of Science And Technology
Manju, Sebastine; Pillai, N G K(Cochin University Of Science And Technology, October 23, 2014)
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Abstract:
Globally most of the conventional fish stocks have reached a state of optimum exploitation or even over-exploitation; efficient utilization of non-conventional resources is necessary to meet the supply-demand gap for protein supply. Mesopelagic fishes can be considered as one such promising resource for the future, if appropriate harvest and post-harvest technologies are developed. Increasing human population and increasing demand for cheaper food fishes has made myctophids a possible potential resource for future exploitation and utilization. Earlier studies indicated the abundance of Diaphus spp. in the eastern and northeastern Arabian Sea. The present study also indicates the dominance of Diaphus spp. in the deep sea trawling grounds of south west coast of India. Commercial viability of the myctophid fishing in the Indian waters has to be worked out. The present catch estimation is based on the Stratified Random Sampling Method from the landing data. As the coverage of sampling area was limited and the gear efficiency was not standardized, the data generated are not precise. A counter check for the estimates is also not possible due to the absence of comparable works in the study area. Fish biomass estimation by acoustics survey coupled with direct fishing would only confirm the accuracy of estimates. Exploratory surveys for new fishing areas to be continued, for gathering the distribution, abundance, biological and ecological data and map the potential fishing ground on a GIS platform and the data should be provided to the commercial entrepreneurs. Generally non-conventional and non-targeted resources are under low fishing pressure and exploitation rates. Low values of fishing mortality and exploitation rates indicate that removal from the stock by fishing was only nominal from the present fishing grounds. The results indicate that the stock is almost at virgin state and remains grossly underexploited. Since the extent of distribution and abundance of the stock in the ecosystem remains to be ascertained, sustainable yield could not be estimated. Also the impact of myctophids harvest, on other commercially important fishes, has to be studied.
Harikrishnan, M; Dr.Madhusoodana,Kurup B(Cochin University Of Science And Technology, September , 1997)
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Abstract:
Macrobrachium rosenbergii (de Man) and M.ide77a
(Hilgendorf) form two commercially important Palaemonid
prawns of the Vembanad lake (9 28' and 10 10’ N and 76
13' and 76 31' E). Both of them were known to have
contributed to a very lucrative fishery during the sixties,
however, in recent years these natural resources have badly
depleted owing to the impact of many man made alterations
brought about in the ecosystem such as habitat reduction,
physical obstruction imposed in the migratory pathway of
these species, pollution hazards, etc,. Changed
environmental conditions and increased fishing pressures
caused persistent alterations in the stock size of these
prawns during the past so many years, however, no serious
attempt was made to monitor the stock size from time to time
and also to bring out the resource characteristics. Though,
the morphotypic differentiation in grow out male population
of M.rosenbergii has been documented, no similar studies
were conducted with regard to natural male and female
population. Based on the data collected during fishery
cruise surveys conducted in Vembanad lake from March '94 to
February '96, population characteristics. postlarval
distribution, fishery and population dynamics of
M.rosenbergii and M.ide77a of the lake were studied in
detail.
Description:
School of
Industrial Fisheries, Cochin University of Science and Technology
Abdussamad, E M; Dr.Gopinatha Menon, N(Cochin University of Science and Technology, June , 2001)
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Abstract:
present work deals with the various aspects of population characteristics of penaeus indicus ,Metapenaeus dobsoni and metapenaeus monoceros during their nursery phase in tidal ponds and adjacent backwaters.Importance of the present study is to suggest scientific basis for the management of penaeid resources in tidal ponds and backwaters based on their biological characteristics to ensure better yield.Seasonal closure of fishing will be effective in improving the size of the shrimp at harvest.Hydrology of tidal ponds varied with location, but showed a common seasonal pattem.Seasonal variation in temperature was very small. It fluctuated between 27.5 to 32.3°C in tidalponds and 26.9 to 29.9°C in open backwaters.Improvement of nursery habitats with due consideration for biological requirements of the resource will ensure better growth, survival and abundance of the stock.The recruitment, growth and emigration data of prawns from their nurseries can be used successfully for fishery forecasting. projecting juvenile growth forward through time, it is possible to establish, which cohort contributes to offshore fishery each year. So, by interpreting the recruitment and growth data of species in their nurseries with offshore catch data, fishery can be forecasted successfully.
Description:
Central Marine Fisheries Research Institute, Kochi
Bindhu,Paul; George,M K(ICAR, CMFRI, November , 2000)
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Abstract:
The thesis contains the results of an investigation on the " Population Genetic Structure of the Penaeus indicus " from southeast and southwest coasts of India. The P.indicus, popularly known as the Indian white prawn, is distributed widely in the Indo-Pacific, starting from New South wales in Australia in the east to the east coast of Africa in the west. Its heavy demand in the export market, the species has been exploited intensively from all along its areas of distribution in Indian waters. The population genetic characteristics of the species were examined by three independent but complementary techniques, namely, morphometrics (truss network), biochemical genetics (isozyme electrophoresis ) and molecular genetics (RFLP and RAPD). The east and west coast populations of the species may be genetically different. Due to certain constraints, the results obtained from the studies of restriction fragment length 70 polymorphism (RFLP) were limited. The significant difference in the number of bands in the sample populations strongly suggests that these two populations have considerably different population genetic structures
Mohandas, N N; Dr.George, M K(Indian Council of Agricultural Research, Central Marine Fisheries Institute, January , 1997)
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Abstract:
The objective of present investigation was to study the population genetic structure of S. longiceps by applying three different basic population genetic techniques such as cytogenetics, non-enzymatic biochemicalgenetics (general protein) and morphomeristics/metrics.
Sreeramana Aithal, P; Nagaraja, H S; Mohan Rao, P; Nampoori, V P N; Vallabhan, C P G; Avasthi, D K(Elsevier, 1997)
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Abstract:
Organic nonlinear optical single crystals of Methyl para-Hydroxy Benzoate (MHB) have been grown using gel-solution technique. These crystals are cut along z-axis and are bombarded with Ag14+ ions of energy 100 MeV. The results show an increase in refractive index at the ion irradiated region. The dielectric constant of the irradiated crystal is increased more than 15 times compared to that of a nonirradiated crystal. The result of these changes and comparative study of second harmonic generation (SHG) efficiency before and after irradiation is discussed.
Somkiate,Sripathar; Dr.Sankaranarayanan, K C(Cochin University of Science and Technology, May 26, 2000)
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Abstract:
This thesis Entitled Post-Environmental Evaluation of The Rajjaprabha Dam In Thailand.
This post evaluation of environmental consequences of Rajjaprabha dam IS conducted ten years after its commencement. The Rajjaprabha dam project was planned and implemented as a multipurpose
project, mainly for hydropower production, flood protection, fisheries, recreation and irrigation. The project includes the dam and reservoir with a 240 MW hydropower plant located about 90 km upstream from Surat Thani province, and irrigation systems covering the coastal plain in Surat Thani. The upstream storage reservoir (with about 5,639 mcm storage) and the hydropower plant had already been implemented. The first phase of irrigation system covers an area of 23,100 hectares. The second phase is envisaged to cover about 50,000 hectares.
This study was conducted with the following objectives: (I) to assess all existing environmental resources and their values with the help of input-output analysis (2) to findout the beneficial impacts of the project (3) to evaluate the actual positive effects vis-a-vis the estimated effects before the project was implemented and (4) to identify all significant changes in relatives to the impacts previously assessed.
The study area includes the Phum Duang river basin of about 4,668 km2 (placed on the areas that are upstream and downstream to the damsite), The duration of study is limited to 10 years after the dam has become operational i.e. from 1987-1997.
The results of the study reveal that there is no significant changes in climatic and ground water resources, with respect to the study area inspte of the fact that the physical and chemical properties of the soil have slightly changed. Sedimentation in the reservoir does not have much effect on the function of the dam.
Description:
Department of Applied Economics, Cochin University of Science and Technology
Dr.Babu, C A; Joseph, P V(Wiley InterScience (www.interscience.wiley.com)., August , 2001)
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We have studied sea surface temperature (SST) anomalies over the Indian and Pacific Oceans (domain 25 °S to 25°N
and 40 °E to 160 °W) during the three seasons following the Indian summer monsoon for wet monsoons and also for
dry monsoons accompanied or not by El Ni˜no. A dry monsoon is followed by positive SST anomalies in the longitude
belt 40 to 120 °E, negative anomalies in 120 to 160 °E and again positive anomalies east of 160 °E. In dry monsoons
accompanied by El Ni˜no the anomalies have the same sign, but are much stronger. Wet monsoons have weak anomalies
of opposite sign in all three of the longitude belts. Thus El Ni˜no and a dry monsoon have the same types of association
with the Indian and Pacific Ocean SSTs.
In the sector 40 to 120 °E SST anomalies first appear over the western part of the Indian Ocean (June to September)
followed by the same sign of anomalies over its eastern part and China Sea (October to March). By March after a dry
monsoon or El Ni˜no the Indian Ocean between 10 °N and 10 °S has a spatially large warm SST anomaly. Anomalies in
deep convection tend to follow the SST anomalies, with warm SST anomalies producing positive convection anomalies
around the seasonal location of the intertropical convergence zone
Pseudomonas aeruginosa MCCB 123 was grown in a synthetic medium for β-1,3 glucanase production. From the
culture filtrate, β-1,3 glucanase was purified with a molecular mass of 45 kDa. The enzyme was a metallozyme as its β-1,3
glucanase activity got inhibited by the metal chelator EDTA. Optimum pH and temperature for β-1,3 glucanase activity on
laminarin was found to be 7 and 50 °C respectively. The MCCB 123 β-1,3 glucanase was found to have good lytic action on
a wide range of fungal isolates, and hence its application in fungal DNA extraction was evaluated. β-1,3 glucanase purified
from the culture supernatant of P. aeruginosa MCCB 123 could be used for the extraction of fungal DNA without the
addition of any other reagents generally used. Optimum pH and temperature of enzyme for fungal DNA extraction was
found to be 7 and 65 °C respectively. This is the first report on β-1,3 glucanase employed in fungal DNA extraction
Description:
Indian Journal of Experimental Biology
Vol.52, January 2014, pp. 89-96
Hatha, A A M; Abhirosh, C; Sherin, V; Thomas, A P; Abhilash, P C(Springer India, August 3, 2010)
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Abstract:
Prevalence of faecal coliform bacteria and the
survival of Escherichia coli, Vibrio parahaemolyticus and
Salmonella paratyphi were studied in the water and sediment
from Vembanadu Lake in the presence and absence
of protozoan predators. The density of faecal coliform bacteria
ranged between mean MPN value 5080–9000/100 ml
in water and 110,000–988,000/1 g in sediment (p <0.01),
which was 110 times greater than in overlying water. The
laboratory microcosm studies revealed that E. coli, V. parahaemolyticus
and S. paratyphi showed significantly higher
survival (p <0.05) potential in sediment than in overlying
water both in the presence and absence of protozoan predators.
The results indicate that Vembanadu Lake sediment
constitutes a reservoir of pathogenic bacteria and exhibits
potential health hazard from possible resuspension and subsequent
ingestion during recreational activities. Therefore,
assessment of bacterial concentration in freshwater lake sediments
used for contact and non-contact recreation is of considerable
significance for the proper assessment of microbial pollution of the overlying water and the management
and protection of related health risk at specific recreational
sites. In addition, assessment of the bacterial concentration
in sediments can be used as a relatively stable indicator of
long-term mean bacterial concentration in the water column
above.
Hatha, A A M; Abhirosh, C; Sherin, V; Thomas, A P; Mazumder, A(Elsevier, March 23, 2011)
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To assess the prevalence of faecal coliform bacteria and multiple drug resistance
among Escherichia coli and Salmonella serotypes from Vembanadu Lake.
Study design: Systematic microbiological testing.
Methods: Monthly collection of water samples were made from ten stations on the southern
and northern parts of a salt water regulator constructed in Vembanadu Lake in order to
prevent incursion of seawater during certain periods of the year. Density of faecal colifrom
bacteria was estimated. E. coli and Salmonella were isolated and their different serotypes
were identified. Antibiotic resistance analysis of E. coli and Salmonella serotypes was done
and the MAR index of individual isolates was calculated.
Results: Density of faecal coliform bacteria ranged from mean MPN value 2900 -7100/100ml.
Results showed multiple drug resistance pattern among the bacterial isolates. E. coli
showed more than 50% resistance to amickacin, oxytetracycline, streptomycin, tetracycline
and kanamycin while Salmonella showed high resistance to oxytetracycline, streptomycin,
tetracycline and ampicillin. The MAR indexing of the isolates showed that they
have originated from high risk source such as humans, poultry and dairy cows.
Conclusions: The high density of faecal coliform bacteria and prevalence of multi drug
resistant E. coli and Salmonella serotypes in the lake may pose severe public health risk
through related water borne and food borne outbreaks
Mahesh,R; Rajasenan, D(Department of Applied Economics, 2006)
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Abstract:
The present study is an attempt to understand the link between natural resource degradation and poverty among people dependent on these resources. This is done by examining the impact of depletion of marine resources on the livelihood and socio-economic condition of the small-scale marine fishery community in South Kerala. In Kerala, nearly ten lakh fisherfolk depend on the marine fishery resources for their livelihood. The overall level of education of the small-scale fishing community is lower than that of the State’s rural population. Almost all the households surveyed, is one way or other, depend on fishery resources for livelihood. Low levels percapita income and high levels of inequality imply the existence of a large proportion of poor people in the community who are vulnerable to external shocks. The study reveals that poverty was comparatively higher among households with no fishing assets, with only one earner, with more than two children, and depending entirely on pensions/remittances. The study has not provided any evidence to show that poverty in the community is the result of depletion of marine resources.
Choudhury, P K(Microwave and Optical Technology Letters, November 25, 2002)
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Abstract:
A fairly rigorous analytical treatment of the power characteristics
of dielectric optical waveguides with Piet Hein core-cross
sectional geometry is presented in this paper. This kind of wareguide
structure would be advantageous owing to the absence of corners,
which are found in rectangular guides, resulting in undesirable loss (hit
to the scattering of light. In order to simplify this theoretical approach.
em approximation of vanishing refractive index difference between the
guiding and the non-guiding sections is implemented. The variation eJ
logarithmic power is shown for different dimensions of the core, corresponding
to different azimuthal modal indices. It is found that the nutlet
with higher index values carry less logaritlunic power in the lower tail
of the propagation 's constant range, and this feature affects the higher
tail. A better kind of uniformity of the power distribution is observed
near the higher tail of the range of propagation Constants