| Abstract: | This thesis deals with the results oi’ investigations on phytoplankton productivity and related aspects conducted in various ecoaystms such as estuarine, inshore and oceanic enviroments and certain special ecosytans including the pu.-awn culture fields and associated many-eves, mud bank and the seas around the Andaman-Nicobar Islands. This study also includes the qualitative and quantitative variations of phytoplankton production, their seasonal abundance, factors controlling the same and the magnitude of the potential resources derived 1!:-om it |
| Description: | central Marine Fisheries Research Institute |
| URI: | http://dyuthi.cusat.ac.in/purl/3629 |
| Files | Size |
|---|---|
| Dyuthi-T1599.pdf | (12.57Mb) |
| Abstract: | Planktonic ostracod of the Indian Ocean have not been studied in detail although extensive studies have been made on them from other oceans, particularly Atlantic. with this view, the present study was undertaken, to throw; some light on the systematics and distribution oi’ planktonic ostracods in this region, This study provides iniormation regarding the distribution or each species in the Northern Indian Ocean, specially in the Bay of Bengal which is the least explored, as far as planlctunio ostracods are concerned. It may also furnish us with the data regarding the nature of ostracod production in this area, which directly reflects on the total productivity as they play an important role in the rapid recycling or organic substances, iaecal pellets and even flocculants In the present study the main objectives are; (1) Proper detemination of the species or planktonic Ostraooda that occur in the area or investigation, (2) to explain the pattern oi’ distribution, (3) to estimate their abundance and to some extent seasonal variation, and (4) to correlate their distribution with the physics-chemical factors of the environment |
| Description: | Indian ocean biological center national institute of oceanography regional centre |
| URI: | http://dyuthi.cusat.ac.in/purl/3278 |
| Files | Size |
|---|---|
| Dyuthi-T1252.pdf | (6.784Mb) |
| Abstract: | True crabs are the most fascinating group of organisms among the decapod crustaceans. Great importance is attached at present to the increased exploitation of these animals and therefore there is great scope for further development of their fishery. They have a broad and hard carapace, massive chelate legs, bent abdomen and exhibit high degree of adaptation to the environment. They show pelagic, benthic, intertidal, burrowing and terrestrial modes of life. Their commensal association with other invertebrates, their breeding behaviour and life history are of great interest to biologists. More than six hundred species of crabs are known to occur in Indian waters and among them about eight species form a regular fishery along the entire stretch of peninsular India (Rao §§_al., 1973) round the year. Crab fishery in India is fast developing and there is vast scope for them as there are many more potential species. Among the various crustacean diets, crabs are celebrated for deliciousness and for nutritional richness. In recent days, crab food items have become more popular and gained global reception. These resources can also be augmented further by culturing them in ponds in the future. Information on biology and ecology of constituent species go a long way not only in effective exploitation and regulation of the respective fishery resources but also helps in evolving a suitable gear for their capture. Information collected on the national level in various aspects as reproduction, growth rate, larval development, parasites, diseases, nutritive values etc. will be of help in evolving a national policy for the effective utilisation and conservation of this resource. They also provide the baseline information for undertaking any purposeful and meaningful culture activities. Information on the various aspects mentioned above is very much restricted in true crabs and hence the present study |
| Description: | School Of Marine Sciences Cochin University Of Science And Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3615 |
| Files | Size |
|---|---|
| Dyuthi-T1573.pdf | (10.67Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1175 |
| Files | Size |
|---|---|
| Mercy Thomas 1985.PDF | (232.5Kb) |
| Abstract: | In the present study. extensive investigations were carried out on various factors affecting the selectivity of prawn gill nets with reference to material, mesh size, coefficient of hanging secolouration. Effect of tidal current on fishing height of prawn gill net and seasonal variation of catch during the course of these investigations were also studied. |
| Description: | Department of Industrial Fisheries. Cochin University of science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3561 |
| Files | Size |
|---|---|
| Dyuthi-T1543.pdf | (13.80Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1195 |
| Files | Size |
|---|---|
| Rosamma Philip 1987.PDF | (509.0Kb) |
| Abstract: | The present study helped to understand the trend in rainfall patterns at smaller spatial scales and the large regional differences in the variability of rainfall. The effect of land use and orography on the diurnal variability is also understood. But a better understanding on the long term variation in rainfall is possible by using a longer dataset,which may provide insight into the rainfall variation over country during the past century. The basic mechanism behind the interannual rainfall variability would be possible with numerical studies using coupled Ocean-Atmosphere models. The regional difference in the active-break conditions points to the significance of regional studies than considering India as a single unit. The underlying dynamics of diurnal variability need to be studied by making use of a high resolution model as the present study could not simulate the local onshore circulation. Also the land use modification in this study, selected a region, which is surrounded by crop land. This implies the high possibility for the conversion of the remaining region to agricultural land. Therefore the study is useful than considering idealized conditions, but the adverse effect of irrigated crop is more than non-irrigated crop. Therefore, such studies would help to understand the climate changes occurred in the recent period. The large accumulation of rainfall between 300-600 m height of western Ghats has been found but the reason behind this need to be studied, which is possible by utilizing datasets that would better represent the orography and landuse over the region in high resolution model. Similarly a detailed analysis is needed to clearly identify the causative relations of the predictors identified with the predictant and the physical reasons behind them. New approaches that include nonlinear relationships and dynamical variables from model simulations can be included in the existing statistical models to improve the skill of the models. Also the statistical models for the forecasts of monsoon have to be continually updated. |
| Description: | Department of Atmospheric Sciences,Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/2952 |
| Files | Size |
|---|---|
| Dyuthi-T0943.pdf | (213.9Mb) |
| Abstract: | In India scientific commercial farming of Macrobrachium is yet to get a start, the major constraint being the lack of seed. Seed collection from the natural sources alone may not be sufficient, and in such cases seed production in hatcheries is inevitable. This necessitates knowledge of the reproductive biology of the species technology development for brood stock and larval rearing, and the optimum conditions required for larval development to undertake large scale seed production.The present study was taken up with the major objectives of developing a proper, simple and feasible technology for the larval rearing of Macrobrachium, with special emphasis on. mass larval rearing suitable for commercial level operations. |
| Description: | Department of Industrial Fisheries, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3218 |
| Files | Size |
|---|---|
| Dyuthi-T1192.pdf | (5.231Mb) |
| Abstract: | The overall focus of the thesis involves Studies on the riverine fishing geara of central kerala.Rivers and reservoirs of India harbour a rich and varied spectrum of fishes exceeding 400 species, which include commercially important fishes.The fish and fisheries play a crucial role in kerala's economy,employment generation ,food security and well being of its people.In the present study ,results of investigations conducted during 2001-2002 on riverine fishing gears of central kerala are presented along with detailed description of fishing gears,their distribution and operation covering aspects of selectivity and operational economics.Chapter I gives an introduction to the topiC of the study highlighting the relevance of the study and reviews of the existing literature on fishing gears and practices in riverine sector and sets out objectives of the study.The chapter 11 deals with the Materials and Methods used for the conduct of the investigations. In this chapter the area and the rivers selected for the study. reasons for the selection process and methodologies used for survey of riverine fishing gaear and investigations on design, structure and operation of different gear systems are presented.The chapter III discusses gillnet and its operation. Gill netting is one of the simplest and oldest methods of fishing. They are the most widely operated fishing gear in the rivers of Central Kerala. Gill netting being a low cost fishing method is of special interest for artisanal fisheries. Twenty different types of gillnets are operated in this sector.Chapter IV deals with cast nets. The origin and evolution of cast net has been briefly described in the introductory part.The chapter V deals with fishing lines, traps and other miscellaneous gears.This findings will be useful for riverine fishermen for deployment of appropriate gear systems during different seasons to ensure profitability of fishing operations. |
| Description: | School of Industrial Fisheries, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3041 |
| Files | Size |
|---|---|
| Dyuthi-T1015.pdf | (6.778Mb) |
| Abstract: | Rubber has become an indispensable material in Ocean technology. Rubber components play critical roles such as sealing, damping, environmental protection, electrical insulation etc. in most under water engineering applications. Technology driven innovations in electro acoustic transducers and other sophisticated end uses have enabled quantum jump in the quality and reliability of rubber components. Under water electro acoustic transducers use rubbers as a critical material in their construction. Work in this field has lead to highly reliable and high performance materials which has enhanced service life of transducers to the extent of 1015 years. Present work concentrates on these materials. Conventional rubbers are inadequate to meet many of the stringent functional of the requirements. There exists large gap of information in the rubber technology of under water rubbers, particularly in the context of under water electro acoustic transducers. Present study is towards filling up the gaps of information in this crucial area. The research work has been in the area of compounding and characterisation of rubbers for use in under water electro acoustic transducers. The study also covers specific material system such as encapsulation material, baffle material, seal material, etc. Life prediction techniques of under water rubbers in general has been established with reference to more than one functional property. This thesis is divided into 6 chapters. |
| Description: | School of marine sciences, Cochin University of Science And Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3436 |
| Files | Size |
|---|---|
| Dyuthi-T1402.pdf | (6.363Mb) |
| Abstract: | This Thesis contains a detailed account of the results of the investigations on the "Studies on sea cucumbers of Minicoy, Lakshadweep" from the Arabian Sea, carried out from January 1990 to December 1991. The results are presented and discussed in six chapters, preceded by an "lntroduction", "Review of literature" and "Materials and Methods". A brief account on the importance of sea-cucumbers, its general morphology, present status of sea-cucumbers and their fishery in India and the major objectives of the present study are given in the "lntroduction" "Review of Literature" has covered and reviewed almost all available published reports and informations on sea-cucumbers on global basis, with special emphasis on Indian region and particularly in Minicoy Island. The Minicoy Island topography particularly the lagoon and reef flat area, discretion of sampling stations, survey on sea-cucumbers in space and time, analysis of samples both in the field and laboratory, statistical analysis of data, etc. and the period of study are given under "Materials and Methods. |
| Description: | School of marine sciences, Central institute of fisheries technology, Cochin University of Science And Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3443 |
| Files | Size |
|---|---|
| Dyuthi-T1404.pdf | (8.084Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/2810 |
| Files | Size |
|---|---|
| Dyuthi-T0831.pdf | (14.82Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1189 |
| Files | Size |
|---|---|
| Prasannakumar S 1987.PDF | (239.0Kb) |
| Abstract: | Sediment transport in the nearshore areas is an important process in deciding the coastline stability. The design and effective maintenance of navigable waterways, harbours and marine structures depend on the stability of the sediment substrate and the nature of sedimentation in the nearshore zone. The nearshore zone is a complex environment and the exact relationships existing between water motions and the resulting sediment transports are not well understood. During the rough weather season, when the sediment movement is considerable, processes occurring in the nearshore area are much less understood. Moreover, there is a general lack of field measurements, especially during the time of severe storm conditions. The increasing pressures and the concern on the preservation of the valuable coastal environment have led to the development of shore protection programmes. Conservation not only demands knowledge of what needs to be done, but also requires the basic processes to be fully understood. Considering the fragile nature of barrier beaches and intense occupancy of these areas by man, these coastal features have long been a subject of study by coastal oceanographers, geomorphologists and engineers. The present study is an attempt to understand the sediment movement in relation to beach dynamics, especially in the surf zone, along some part of Kerala coast and the response of the beaches to various forcing functions over different seasons |
| Description: | School Of Marine Sciences Cochin University Of Science And Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3665 |
| Files | Size |
|---|---|
| Dyuthi-T1585.pdf | (5.449Mb) |
| Abstract: | Available information on abundance of myctophids and their utilisation indicate that there is excellent scope for development of myctophid fisheries in Indian Ocean. Most of the conventional fish stocks have reached a state of full exploitation or over-exploitation. Hence there is need to locate new and conventional fishery resources in order to fill in the supply-demand gap, in the face of increasing demand for fish. Information on length-weight relationship, age and growth, spawning season, fecundity and age at maturity and information on bycatch discards are required for sustainable utilization of myctophid resource in the Indian Ocean |
| Description: | A study about global fishery resources and its production |
| URI: | http://dyuthi.cusat.ac.in/purl/5040 |
| Files | Size |
|---|---|
| Dyuthi-T2105.pdf | (18.31Mb) |
| Abstract: | The present study is an attempt to elucidate the sedimentation regime of the harbour and its environment. These investigations include detailed studies on the hydrography' of the harbour region of the estuary, estuarine circulation, spatial and temporal variations of the amount and texture of bottom sediments. A note on the dredging is also given in the Annexure .The thesis is presented in six chapters |
| Description: | School of Marine Sciences, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3636 |
| Files | Size |
|---|---|
| Dyuthi-T1615.pdf | (5.152Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1235 |
| Files | Size |
|---|---|
| Sundaresan Pillai J 1989.PDF | (585.2Kb) |
| Abstract: | The thesis is a study undertaken to understand the distribution pattern of Q nega in Cochin waters for better exploitation of the resource and to learn the biological aspects of the animal which has a direct bearing on its utilization for producing different products .The study also presents a thorough knowledge on the size groups available during different seasons for judicious exploitation and utilization of the resource and the changes in the biochemical composition of Q nega during different seasons so as to utilize it properly for producing suitable products throughout the year. The thesis also tests the suitability of the material for producing different products and to test the acceptability of the same for human consumption. The study also aims to show that Squilla can be utilized for the production of industrial products like chitin and chitosan. |
| Description: | School of Industrial Fisheries, Cochin University of Science and Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3203 |
| Files | Size |
|---|---|
| Dyuthi-T1177.pdf | (3.295Mb) |
| Abstract: | Based on the adaption of fishes to their habitat, they are divided into three ecological groups - marine, fresh water and estuarine or brackish water forms. Estuarine fishes inhabit the less saline region of the sea, estuaries and other inland waters. These fishes are more subjected to pollution than fresh water fishes or marine fishes as they encounter pollutants present in the outgoing river water and the incoming sea water during low and high tides respectively. So, the study of the biology of the estuarine fishes has become unavoidable to assess their suitability in aquaculture. The development of both capture and culture fisheries related to any brackish water system is dependent on the availability of scientific‘ data on the various biological factors in respect of the different species. Such a study on fishes will be helpful in formulating suitable schemes for the management of brackish water for capture and culture fisheries. It was therefore felt that a study of the biological and biochemical aspects of two estuarine fishes Megalops cyprinoides Broussonet and Scatophargus Bloch which are not fully exploited in aquaculture programmes, was worth undertaking. The present study is expected to advance our knowledge on the biology of the two fishes which are very desirable for brackish water fish farming |
| Description: | School of Marine Sciences,Cochin University Of Science And Technology |
| URI: | http://dyuthi.cusat.ac.in/purl/3429 |
| Files | Size |
|---|---|
| Dyuthi-T1413.pdf | (7.262Mb) |
| URI: | http://dyuthi.cusat.ac.in/purl/1236 |
| Files | Size |
|---|---|
| Anney K Mathew 1989.PDF | (471.1Kb) |
Dyuthi Digital Repository Copyright © 2007-2011 Cochin University of Science and Technology. Items in Dyuthi are protected by copyright, with all rights reserved, unless otherwise indicated.