Abstract: | The tremendous growth in industrial production and the consequent improving in the standards of living have provoked worldwide discussion on environmental quality. The question of abusive use of pesticides for crop protection and vector control programmes is only one aspect of this entire complex. Inspite of this, tendentious publications such as Rachel Carson’s Silent spring have brought crop protection into the foreground of environmental discussions. The persistence and high stability of organochlorine pesticides are regarded as problematic and the accumulation of pesticides residues and its metabolites in the different compartments of the environment is one of the major concerns. Because of their persistence in the aquatic environment and biomagnifications in food chain, the continuous use of pesticides will have wider implications not only in aquatic environmental quality but also on human health. The residual levels of these persistent chemicals exceed their permissible limits, and get partitioned among the constituent phases of the aquatic systems. Crop protection is only part of the agricultural economy and in agriculture itself has led to the most fundamental changes in the human environment. So, in all areas of life one must weigh the desired advantages against possible disadvantages. The proposed thesis is based on the investigations on the distributions of organochlorine and organophosphorus pesticides in the waters and sediments of Kuttanad backwaters. Kuttanad, a unique agricultural area, which forms the southern part of the Vembanad lake, is a deltaic formation of four river systems entering the southern part of the Cochin estuary. No systematic study has ever been done to assess the ecotoxicological impact of these diverse chemicals and their metabolites in Kuttanad area. So, a detailed systematic and rigorous investigation on the distributions of these persistent chemicals is carried out. The thesis is divided into 7 Chapters |
Description: | Department of Chemical Oceanography, School of Marine Sciences, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3442 |
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Dyuthi-T1418.pdf | (6.281Mb) |
Description: | Department of Marine Geology and Geophysics,Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/2671 |
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Dyuthi-T0723.pdf | (5.235Mb) |
Abstract: | Industrial pollutants, consisting of heavy metals, petroleum residues, petrochemicals, and a wide spectrum of pesticides, enter the marine environment on a massive scale and pose a very serious threat to all forms of aquatic life. Although, earlier, efforts were directed towards the identification of pollutants and their major sources, because of a growing apprehension about the potential harm that pesticides can inflict upon various aquatic fauna and flora, research on fundamental and applied aspects of pesticides in the aquatic environment has mushroomed to a point where it has become difficult to even keep track of the current advances and developments. The Cochin Estuarine System (CES), adjoining the Greater Cochin area, receives considerable amounts of domestic sewage, urban wastes, agricultural runoff as well as effluent from the industrial units spread all along its shores. Since preliminary investigations revealed that the most prominent of organic pollutants discharged to these estuarine waters were the pesticides, the present study was designed to analyse the temporal and spatial distribution profile of some of the more toxic, persistent pesticides ——— organochlorines such as DDT and their metabolites; HCH-isomers; a cyclodiene compound," Endosulfan and a widely distributed, easily degradable, organophosphorus compound, Malathion, besides investigating their sorptional and toxicological characteristics. Although, there were indications of widespread contamination of various regions of the CBS with DDT, HCH-isomers etc., due to inadequacies of the monitoring programmes and due to a glaring void of baseline data the causative factors could not identified authentically. Therefore, seasonal and spatial distributions of some of the more commonly used pesticides in the CES were monitored systematically, (employing Gas Chromatographic techniques) and the results are analysed. |
Description: | Chemical Oceanography Division, School of Marine Sciences, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3200 |
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Dyuthi-T1174.pdf | (3.767Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/5329 |
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Dyuthi T-2365.pdf | (15.65Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/5139 |
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Dyuthi-T2173.pdf | (6.406Mb) |
Abstract: | The present scenario of industrial fishing in India is that most of large trawlers are based at Visakhapatnam and congregate in the potential shrimp ground in the upper East coast of India commonly known as the Sandheads. These are outriggcr vessels operating two or four trawl nets along with a testing trawl called try net. In the early Seventies these vessels were operating on a very high economic return which was evident from the steady increase in number of outriggers over a period of twenty years. Since the total allowable catch has to be shared by all vessels including the increasing fleet, reduction per vessel output is bound to happen. Therefore some of them could not survive the competition and withdrew from the scene. The number of outriggers did not increase subsequently. However, there arose a doubt whether the existing fleet of about 180 vessels are fishing economically or whether there is any scope for further introduction of industrial vessels in the region. This study is focussing to the techno economic aspects of industrial fishing in the upper East coast of India |
Description: | Department of Industrial Fisheries, Cochin University of Science and Technology, |
URI: | http://dyuthi.cusat.ac.in/purl/3363 |
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Dyuthi-T1340.pdf | (8.641Mb) |
Abstract: | In the present study an attempt has been made to understand the microzooplankton community along the easr coast of India. Most of the earlier studies projected Bay of Bengal as an oligotrophic system where phytoplankton growth is limited by a number of factors among which nutrients are the foremost. Hence it is logical to consider that the most of the primary production in the Bay of Bengal could be contributed by small sized phytoplankton harnessing the available resources, which in turn can be utilized effiency by the microzooplankton only. Hence microzooplankton could play in transferring primary organic carbon to higher tropic levels in this region. |
URI: | http://dyuthi.cusat.ac.in/xmlui/purl/2089 |
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Dyuthi-T0400.pdf | (14.91Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/2882 |
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Dyuthi-T0879.pdf | (7.102Mb) |
Abstract: | The great number of parasitic species of marine and brackishwater animals that have been described indicates that parasites play an important part in the ecology of the oceans and brackishwaters. Jnspite of their importance, marine and brackish parasites are probably the least known group of organisms. Considering the large number of marine and brackishwater hosts, especially in the tropics, it is no exaggeration to say that the description of marine and brackishwater parasites has hardly begun (Rohde, 1982). With this view in mind, an attempt has been made to study the ecobiology of the helminth parasites of finfishes and shellfishes of eochin waters with special reference to digenetic trematodes. The work is broadly divided into three chapters, Chapter 1 consists of a description of the study area, prevalence of infection and concurrent infections with helminth parasites, seasonal variation, host specificity> and zoogeography of digenetic trematodes; Chapter II deals with the systematics of digenetic trematodes; and Chapter III deals with studies on larval trematodes from molluscs and crustacea, adult from a molluscan host, life-cycle, biology and histopathology |
Description: | School of Marine Sciences, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3648 |
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Dyuthi-T1623.pdf | (13.49Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/1214 |
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Syed Ismail Koya 1988.PDF | (441.5Kb) |
Abstract: | The main objectives of the present investigation were to evaluate the qualitative and quantitative distribution of natural cyanobacterial population and their ecobiological properties along the Cochin estuary and their application in aquaculture systems as a nutritional supplement due to their nutrient-rich biochemical composition and antioxidant potential. This thesis presents a detailed account of the distribution of cyanobacteria in Cochin estuary, an assessment of physico-chemical parameters and the nutrients of the study site, an evaluation of the effect of physico-chemical parameters on cyanobacterial distribution and abundance, isolation, identification and culturing of cyanobacteria, the biochemical composition an productivity of cyanobacteria, and an evaluation of the potential of the selected cyanobacteria as antioxidants against ethanol induced lipid peroxidation. The pH, salinity and nutritional requirements were optimized for low-cost production of the selected cyanobacterial strains. The present study provides an insight into the distribution, abundance, diversity and ecology of cyanobacteria of Cochin estuary. From the results, it is evident that the ecological conditions of Cochin estuary support a rich cyanobacterial growth. |
URI: | http://dyuthi.cusat.ac.in/purl/914 |
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Dyuthi-T0070.pdf | (4.047Mb) |
Abstract: | Prawn culture by traditional method forms an important occupation for the people in these areas, especially in the Vypeen island. Though short term studies have been made on various aspects of prawn culture field and its ecology, a study of detailed nature covering perennial, seasonal, fields and canals between coconut plantation is lacking from these areas. This study will also enable to assess the relative productivity of different systems during different seasons and the influence of the environment on the production potentials. Therefore the present study is taken upto throw more light on the ecological characteristics of these fields with special emphasis on its primary, secondary and tertiary production. The present area of investigation includes the prawn culture fields adjacent to Cochin backwater. The Cochin backwater (O9° 58'N 76° 28'E) is a shallow semi-enclosed body of water of tropical estuary. A narrow gut, about 450 M wide forms its main connection with the Arabian sea and this region is subjected to regular tidal influenceertiary production. |
Description: | Central Marine Fisheries Research Institute |
URI: | http://dyuthi.cusat.ac.in/purl/3231 |
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Dyuthi-T1205.pdf | (2.766Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/2881 |
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Dyuthi-T0878.pdf | (8.780Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/5434 |
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Dyuthi T-2475.pdf | (50.85Mb) |
Abstract: | This thesis entitled ecology of chaetognaths in the indian EEZ.The present study, in general, deals with the distribution pattern of mesozooplankton biomass and abundance with special reference to the detailed ecology of the important carnivorous planktonic group, the chaetognath, in the two major ocean basins of the Indian EEZ, the Arabian Sea (AS) and the Bay of Bengal (BoB). Prior to the International Indian Ocean expedition (IIOE, 1960 – 1965), cmprehensive studies on chaetognath in the Indian waters were very limited and was confined mostly to some coastal and oceanic regions. The study revealed a profound influence of different physical process on the abundance of chaetognath community. The significant influence exerted by different physico-chemical factors on the vertical distribution of chaetognath species was also evident. Prior to this study, only very little information was available on the ecology and distribution pattern chaetognaths in both the Arabian sea and the Bay of Bengal in relation to various mesoscale processes and physicochemical .variables. This study, emphasizing the short term and long term influences of different meso-scale and basin scale physical events on the ecology of this important plankton group provides the baseline data for extensive ecological research on any major mesozooplankton group in this tropical low latitude region. |
Description: | National Institute of Oceanography |
URI: | http://dyuthi.cusat.ac.in/purl/3075 |
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Dyuthi-T1049.pdf | (5.807Mb) |
URI: | http://dyuthi.cusat.ac.in/purl/5325 |
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Dyuthi T-2361.pdf | (17.08Mb) |
Abstract: | Comprehensive studies integrating production, consumption and marketing of ornamental fishes were never conducted in the past in Kerala and this study is an attempt to highlight the dynamics in a systematic manner by making a primary empirical study. The advantages of such an approach are many. First, the study entails detailed empirical data under a given time frame on various inter linked economic activities in ornamental fisheries sector. Second, the study tries to improve upon the previous discipline-bound studies by adopting an integrated approach. As Kerala has diverse ecological and climatic conditions, case studies on various ornamental fish production systems help identifying suitable culture practice for selected environmental conditions. One of the major conclusions of this study as explained in the concluding chapter is that although Kerala is blessed with favourable geographic and climatic conditions needed for developing ornamental fishery, diverse local conditions and requirements contain adopting modern methods of enterprise development.Consumer studies conducted would help to identify the demand of ornamental fishes and the factors leading to it. Market studies would help in understanding the forces behind domestic market, which is very promising, but neglected. Viability studies throw light on the economic performance of both the production systems and the trading units of ornamental fishes. Despite the economic significance of ornamental fisheries industry, its development has been constrained due to various bio-technical, cultural, socio-economic, organisational and above all, institutional and policy failures. The outcome of the study would identify constraints facing the industry and institutional arrangements for development. |
Description: | School of Industrial Fisheries, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/2828 |
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Dyuthi-T0849.pdf | (7.170Mb) |
Abstract: | The world demand for fish and fishery products is increasing steadily and it is generally accepted that it will not be possible to meet the heavy demand with resources exploited from capture fishery alone. Now aquaculture is well established and fastdeveloping industry in many countries and is a major focus sector for development. During recent decades, aquaculture has gained momentum, throughout the world especially in developing countries. According to Food and Agricultural Oganisation (FAO, 2000), global aquaculture production was 26.38 tones in 1996 have reached 32.9 million tonnes during 1999. Only marine aquaculture sector has contributed 13.1 million tonnes during 1999.India is a major fish producing country. About one half of lndia’s brackish water lands are currently being utilized for farming in order to reduce the gap between supply and demand for fish. Aquaculture has become a major source of livelihood for people and its role in integrated rural development, generation of employment and earning foreign exchange, thereby alleviating poverty is being greatly appreciated around the world.Among the infectious agents, bacteria are becoming the prime causal organisms for diseases in food fishes and other marine animals. Sindermann, (1970) reported that bacterial fish pathogen most commonly found among marine fishes is species of Pseudomonas, Vibrio and Mycobacterium. These can be categorized into primary pathogens; secondary invaders that may cause systemic disease in immunocompromised hosts; and normal marine flora which are not pathogenic but may occur on body surfaces or even within the tissues of the host. I-Iigh density of animals in hatchery tanks and ponds is conducive to the spread of pathogen and the aquatic environment with regular application of protein rich feed, is ideal for culturing bacteria. Bacteria, which are normally present in seawater or on the surface of fish, can invade and cause pathological effects in fishes, which are injured or subjected to other environmental stresses.Mycobacteria except parasites are known as nontuberculosis mycobacteria (NTM), atypical mycobacteria or mycobacteria other than tuberculosis(MO'l'l"). This group of mycobacteria includes opportunistic pathogens and saprophytes. Environmental mycobacteria are ubiquitous in distribution and the sources may include soil, water, warm-blooded as well as cold-blooded animals. Disease caused by environmental mycobacterial strains in susceptible humans (Goslee & Wolinsky, 1976; Grange, 1987), animals and fishes are increasingly attracting attention. Greatest importance of environmental mycobacteria is believed to be their role in immunological priming of humans and animals, thereby modifying their immune responses to subsequent exposure to pathogenic species. |
URI: | http://dyuthi.cusat.ac.in/purl/3011 |
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Dyuthi-T0990.pdf | (10.47Mb) |
Abstract: | The heavy metal contamination in the environment may lead to circumstances like bioaccumulation and inturn biomagnification. Hence cheaper and effective technologies are needed to protect the precious natural resources and biological lives. A suitable technique is the one which meets the technical and environmental criteria for dealing with a particular remediation problem and should be site-specific due to spatial and climatic variations and it may not economically feasible everywhere. The search for newer technologies for the environmental therapy, involving the removal of toxic metals from wastewaters has directed attention to adsorption, based on metal binding capacities of various adsorbent materials. Therefore, the present study aim to identify and evaluate the most current mathematical formulations describing sorption processes. Although vast amount of research has been carried out in the area of metal removal by adsorption process using activated carbon few specific research data are available in different scientific institutions. The present work highlights the seasonal and spatial variations in the distribution of some selected heavy metals among various geochemical phases of Cochin Estuarine system and also looked into an environmental theraptic/remedial approach by adsorption technique using activated charcoal and chitosan, to reduce and thereby controlling metallic pollution. The thesis has been addressed in seven chapters with further subdivisions. The first chapter is introductory, stating the necessity of reducing or preventing water pollution due to the hazardous impact on environment and health of living organisms and drawing it from a careful review of literature relevant to the present study. It provides a constricted description about the study area, geology, and general hydrology and also bears the major objectives and scope of the present study. |
Description: | Department Of Chemical Oceanography School Of Marine Sciences Cochin University Of Science And Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3531 |
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Dyuthi-T1462.pdf | (12.24Mb) |
Abstract: | The pollutants discharged into the estuaries are originate from two main sources-industrial and sewage. The former may be toxic which includes heavy metals, residues from antifouling paint particles and pesticides, while large discharges of sewage will contain pathogenic microorganisms. The contamination is enough to destroy the amenities of the waterfront, and the toxic substances may completely destroy the marine life and damage to birds, fishes and other marine organisms. Antifouling biocides are a type of chemical used in marine structure to prevent biofouling. These antifouling biocides gradually leach from the ships and other marine structures into water and finally settled in sediments. Once a saturation adsorption is reached they desorbed into overlying water and causes threat to marine organisms. Previous reports explained the imposex and shell thickening in bivalves owing to the effect of biocides. So bivalves are used as indicator organisms to understand the status of pollution. The nervous system is one of the best body part to understand the effect of toxicant. Acetylcholine esterase enzyme which is the main neurotransmitter in nervous was used to understand the effect of pollutants. Present study uses Acetylcholine esterase enzyme as pollution monitoring indicator |
Description: | Department of Chemical Oceanography School of Marine Sciences Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3752 |
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Dyuthi-T1714.pdf | (18.79Mb) |
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