Jasmine, P; Dr.Saramma, Panampunnayil U(Cochin University Of Science And Technology, January 16, 2009)
[+]
[-]
Abstract:
The Arabian Sea and the Bay of Bengal are both highly
dynamic ecosystems, due to the seasonally reversing monsoon winds,
but the processes affecting the mesozooplankton community remain
poorly understood. These are important basins exhibiting enhanced
biological production as a result of upwelling, winter cooling and
other episodic events such as eddies and gyres. Zooplankters are
primarily the prey for almost all fish larvae. Seasonal changes in the
biogeochemical processes can strongly affect zooplankton density
and distribution, which in turn, strongly affect the larval growth, and
consequently, the pelagic fish recruitment. It is clear that plankton
biomass and biogeochemical fluxes are not in steady state. Acoustic
data on mesozooplankton abundance suggests that they also exist in
the mesopelagic zone. Earlier studies were confined only to the upper
200 m and hence the structure of mesozooplankton community in the
deeper layers was not well known. Copepods are the dominant
mesoplankton group, and therefore the majority of the studies were
focused on them. The planktonic ostracods are the second major
crustacean group and at times, their swarms can outnumber all other
planktonic groups. The understanding of the community structure of
the ostracods is essential to establish their role in the marine food
web. Mesozooplankton is responsible for the vertical flux of organic
matter produced by phytoplankton and is assumed to be equivalent to
new production (Eppley & Peterson, 1979). Since the fate of newly
produced organic matter depends upon their consumers, the
zooplankton biomass must be estimated in size fractions or
taxonomic components to understand the vertical flux of organic
carbon. It is thus important to update our knowledge on different
groups of zooplankton on the basis of seasonal and temporal
distribution. The distribution in space and time is essential for
modeling the carbon cycling that structure the marine ecosystems
Description:
Department Of Marine Sciences,Cochin
University of Science and Technology
Rajendran, C G; Dr.Damodaran,R(Cochin University of Science & Technology, 1995)
[+]
[-]
Abstract:
The investigation was aimed at establishing the effect of salinity on the culture performance of Peneus Indicus in pokkali fields and also to find out the growth performance of the shrimp at varying salinities. The experiments were laid out at Rice Research Station, Vyttila of Kerala Agriculture University in three fields of area 1000 m2 each. The results of the experiment clearly establish that shrimps when stocked at higher salinity (20-25 ppt) for 45 days has given higher growth, survival and production than those stocked at lower salinity (10-15 ppt) in all the above parameters even when the culture experiment was maintained for longer periods in lower salinity. In the prolonged culture experiments conducted for 120 days in 10-25 ppt salinity, the results were poorer than the short period culture in higher salinity and the production values similar to lower saline culture. This clearly establishes the importance of salinity as an ecological factor which will have profound influence in shrimp farming operations.
Description:
Division of Marine Biology, Microbiology and Biochemistry, School of Marine Sciences, Cochin University of Science and Technology
Baiju,K R; Nambiar,C G(Cochin University of Science and Technology, September , 2006)
[+]
[-]
Abstract:
The present research is aimed at studying the charnockites and associated rocks of the Madurai Granulite Block (MGB), especially in terms of their field settings, texture, mineralogy, and mineral chemistry analyzing their petrogenesis with the help of thermobarometrical studies and geochronological constraints. The mechanism of charnockitization by the influx of CO2 rich fluids and its relation to the graphite mineralization is actually a matter of discussion and study. The objectives of the present study are, to delineate petrological and structural relationship of charnockites and associated gneissic rocks, to study the field and petrogenetic aspects of graphite mineralization in the MGB, to establish and re-evaluate the P-T conditions of formation of the rocks with the aid of thermbarometric computations and to compare with the earlier studies, characterization of graphite with XRD, Raman spectroscopy and isotope studies together with a search in to its genesis and its relation to the high-grade metamorphism of the terrain, to evaluate the role of CO2 bearing fluids in the processes of charnockitization as well as in the genesis of graphite within the high-grade terrain and to delineate the metamorphic geochronology of selected rocks using ‘monazite dating’ technique with EPMA.
Krishnamurthy,V; Dr.Samuel, C T(Cochin University of Science and Technology, July , 1985)
[+]
[-]
Abstract:
The thesis deals with the bacterial flora of the Cochin backwaters. Sediment and the prawns
caught from these backwaters in quantitative and qualitative terms, their growth in relation to temperature, their susceptibility to various antibiotics, their role in terms of food for juvenile prawns and the presence of bacteria of public health significance. According to the researcher such a comprehensive study would be of some relevance to shell-fish processing industries apart from its academic value. The effect of antibiotics on the bacteria and the utility of bacteria as food for the juvenile prawns are studied and presented in different chapters.
Description:
School of Marine Science, Department of Industrial fisheries, Cochin University of Science and Technology
Rathna Kala, R; Dr.Chandrika, V(Cochin University of Science and Technology, 2000)
[+]
[-]
Abstract:
The present study on "Microbial production of antibiotics from mangrove ecosystem” was carried out for a period of one year in four selected Stations, Mangalavana, Narakkal, Puthuvyppu and light house area of Puthuvyppu (9°55' — 10°10'N and 76°10‘ - 76°20'E) from January to December 1991. Though much emphasis has been given to occurrence and distribution of actinomycetes, an attempt was also made to understand the distribution patterns of other micro flora in the sediments. Data on physico-chemical parameters were also collected to find out their relationship if any with the microflora. The principle interest of the present investigation is to determineseasonal variations of antagonistic actinomycetes in selected mangrove ecosystem. The microbial interrelationship in mangrove sediments was found out by constructing the ratio between bacteria and actinomycetes, bacteria and fungi, fungi and actinomycetes. In addition temperature, pH, salinity, dissolved oxygen and organic carbon were determined seasonally and their possible relationship was statistically analyzed and the results are presented. Isolated actinomycetes were subjected to cross streak assay to know their nature of antibiotic activity against test fish pathogens and crude antibiotics were extracted from selected isolates and their inhibitory activity is studied and the results are discussed.
Lathika Cicily, Thomas; Bijoy Nandan, S(Cochin University of Science And Technology, February , 2015)
[+]
[-]
Abstract:
The overall attempt of the study was aimed to understand the
microphytoplankton community composition and its variations along a highly
complex and dynamic marine ecosystem, the northern Arabian Sea. The data
generated provides a first of its kind knowledge on the major primary
producers of the region. There appears significant response among the
microphytoplankton community structure towards the variations in the
hydrographic conditions during the winter monsoon period. Interannually,
variations were observed within the microphytoplankton community associated
with the variability in temperature patterns and the intensity of convective
mixing. Changing bloom pattern and dominating species among the
phytoplankton community open new frontiers and vistas towards more intense
study on the biological responses towards physical processes. The production
of large amount of organic matter as a result of intense blooming of Noctiluca
as well as diatoms aggregations augment the particulate organic substances in
these ecosystem. This definitely influences the carbon dynamics of the
northern Arabian Sea. Detailed investigations based on time series as well as
trophodynamic studies are necessary to elucidate the carbon flux and
associated impacts of winter-spring blooms in NEAS. Arabian sea is
considered as one among the hotspot for carbon dynamics and the pioneering
records on the major primary producers fuels carbon based export production
studies and provides a platform for future research. Moreover upcoming
researches based on satellite based remote sensing on productivity patterns
utilizes these insitu observations and taxonomic data sets of phytoplankton for
validation of bloom specific algorithm development and its implementation.
Furthermore Saurashtra coast is considered as a major fishing zone of Indian
EEZ. The studies on the phytoplankton in these regions provide valuable raw
data for fishery prediction models and identifying fishing zones. With the
Summary and Conclusion
177
baseline data obtained further trophodynamic studies can be initiated in the
complex productive North Eastern Arabian Seas (NEAS) ecosystem that is still
remaining unexplored.
Terry Mechado; Dr.Seralathan, P(Cochin University Of Science And Technology, April 12, 1995)
[+]
[-]
Abstract:
Continental shelf is of particular significance in marine geology ,
because it links the two basically different structural zones in the earth's crust; the
continents and ocean basins. The shelf area has much wider importance in many
fields of activity such as scientific, economic, social, political and strategic. The
pace of development has ultimately put pressure on mankind to look for exploitable
resources and accessibility to the continental shelf area and beyond. Added to the
above, the developmental activities in the coastal area would readily and directly
influence the innershelf sediments. This situation demands a thorough geological
knowledge of the continental shelf area. Moreover, a successful management of
the continental shelf zone requires an optimum data base on the physico-chemical
nature of the shelf sediments. Although sedimentological studies were carried out
along the western continental shelf of India, a well documented systematic study
of the inner shelf off Trivandrum coast is still found to be lacking. Considering the
physiographic settings and the vicinity of two renowned placer deposits at Chavara
and Manavalakurichi, such a sedimetological inventory has become all the more
vital.
In view of the above, a research programme has been drawn up to
account the salient sedimentological and mineralogical aspects of the innershelf
and beach sediments between Paravur and Kovalam, Trivandrum district, Kerala
(latitudes 8° 7'00" to 8° 47'45" and longitudes 76°43'00" to 77° 40'45"). The
findings are presented in six chapters formatted to address the aim of this
research.
Description:
Marine Geology Division
School of Marine Sciences
Cochin University of Science And Technology
Maheswaran, P A; Revichandran, C(NATIONAL INSTITUTE OF OCEANOGRAPHY, August , 2004)
[+]
[-]
Abstract:
In this thesis, a detailed attempt has been made to understand the general hydrography of the upper 300m of the water column, in the eastern Arabian Sea and the western Bay of Bengal, the two contrasting basins in the northern Indian Ocean, using recently collected data sets of Marine Research-Living Resources (MR-LR) assessment programme, funded by Department of Ocean Development, from various cruises, pertaining to different seasons. Initially it discuss the general hydrography of the west and east coasts of India are covered, in the context of mixed layer processes. The study describes the materials and methods . To compare the hydrography of the AS and BOB, a unique MLD(Mixed Layer Depth) definition for AS and BOB is essential, for which the 275 CTD profiles were used. A comparison has been made among the various MLD criteria with the actual MLD.
The monthly evolution of MLD, barrier layer thickness and the role of atmospheric forcing on the dynamics of the mixed layer in the AS and BOB were studied. The general hydrography along the west coast of India is described. The upwelling/downwelling, winter cooling processes, in the context of chemical and biological parameters, are also addressed. Finally the general hydrography of the Bay of Bengal is covered. The most striking feature in the hydrography are the signature of an anticyclonic subtropical gyre during spring intermonsoon and a cold core eddy during winter monsoon. The TTS(Typical Tropical Structure) of the euphotic layer was also investigated.
Chandramohan,T; Balachand,A N(Dept. of Physical Oceanography,Faculty of Marine Sciences, 2006)
[+]
[-]
Abstract:
It is proposed to study the suspended sediment transport characteristics of river basins of Kerala and to model suspended sediment discharge mechanism for typical micro-watersheds. The Pamba river basin is selected as a representative hydrologic regime for detailed studies of suspended sediment characteristics and its seasonal variation. The applicability of various erosion models would be tested by comparing with the observed event data (by continuous monitoring of rainfall, discharge, and suspended sediment concentration for lower order streams). Empirical, conceptual and physically distributed models were used for making the comparison of performance of the models. Large variations in the discharge and sediment quantities were noticed during a particular year between the river basins investigated and for an individual river basin during the years for which the data was available. In general, the sediment yield pattern follows the seasonal distribution of rainfall, discharge and physiography of the land. This confirms with similar studies made for other Indian rivers. It was observed from this study, that the quantity of sediment transported downstream shows a decreasing trend over the years corresponding to increase in discharge. For sound and sustainable management of coastal zones, it is important to understand the balance between erosion and retention and to quantify the exact amount of the sediments reaching this eco-system. This, of course, necessitates a good length of time series data and more focused research on the behaviour of each river system, both present and past. In this realm of river inputs to ocean system, each of the 41 rivers of Kerala may have dominant yet diversified roles to influence the coastal ecosystem as reflected from this study on the major fraction of transport, namely the suspended sediments
Geetha, R; Chandramohanakumar, N(Department of Chemical Oceanography,School of marine sciences, 2002)
[+]
[-]
Abstract:
The mangrove ecosystem is one of the earth’s most endangered ecosystems. In this study, geochemical features of three mangrove ecosystems, Mangalavanam, Vypeen and Nettoor were compared. Water, sediment and core samples were collected from these stations for a period of one year. Nutrients, organic compounds orgnic carbon and hydrographical parameters of the samples were estimated. The present study revealed higher concentration of carbon in the surface sediments. The major temporary or ultimate sink for various pollutants in estuaries is the sedimentary reservoir, including intertidal areas. In the present study, higher values for dissolved nutrients, POC and carbohydrates were observed during low tide.
Afsal, V V; Dr Rosamma Philip(Cochin University of Science and Technology, June 9, 2015)
[+]
[-]
Abstract:
Most living organisms are constantly exposed to potentially harmful pathogens. It is the immune system of the organism that enables it to survive in an environment loaded with dangerous pathogenic microorganisms. The innate immunity provides organisms with a rapid and non-specific first line of defense against pathogens. It includes physical barriers such as skin and mucous membranes and chemical barriers including the high acidity of gastric juice, and specialized soluble molecules that possess antimicrobial activity. One of the well-known innate immune defense mechanisms is the production of antimicrobial substances by specific cells or tissues of the organisms. Antimicrobial peptides (AMPs) are such natural substances that
Naveen Sathyan; Dr. Rosamma Philip(Cochin University of Science and Technology, May 5, 2015)
[+]
[-]
Abstract:
Antimicrobial peptides (AMPs) are gene encoded, small sized, generally cationic, amphiphathic peptides characterized by antimicrobial activity against bacteria, fungi, viruses and other pathogens. They are a major component of the innate immune defense system of almost all living organisms, ranging from bacteria to humans and represent the first line of defense against the invading microbial pathogens (Boman, 1995; Zasloff, 2002). Antimicrobial peptides represent a heterogeneous group displaying multiple modes of action that are determined by the sequence and concentration of peptides. Their remarkable specificity for prokaryotes with low toxicity for eukaryotic cells has favored their investigation and exploitation as new antibiotics