Abish, B; Dr.Mohan Kumar, K(Cochin University of Science and Technology, April , 2011)
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Abstract:
This doctoral thesis addresses the growing concern about the significant changes in the climatic and weather patterns due to the aerosol loading that have taken place in the Indo Gangetic Plain(IGP)which includes most of the Northern Indian region. The study region comprises of major industrial cities in India (New Delhi, Kanpur, Allahabad, Jamshedpur and Kolkata). Northern and central parts of India are one of the most thickly populated areas in the world and have the most intensely farmed areas. Rapid increase in population and urbanization has resulted in an abrupt increase in aerosol concentrations in recent years. The IGP has a major source of coal; therefore most of the industries including numerous thermal power plants that run on coal are located around this region. They inject copious amount of aerosols into the atmosphere. Moreover, the transport of dust aerosols from arid locations is prevalent during the dry months which increase the aerosol loading in theatmosphere. The topography of the place is also ideal for the congregation of aerosols. It is bounded by the Himalayas in the north, Thar Desert in the west, the Vindhyan range in the south and Brahmaputra ridge in the east. During the non‐monsoon months (October to May) the weather in the location is dry with very little rainfall. Surface winds are weak during most of the time in this dry season. The aerosols that reach the location by means of long distance transport and from regional sources get accumulated under these favourable conditions.
The increase in aerosol concentration due to the complex combination of aerosol transport and anthropogenic factors mixed with the contribution from the natural sources alters the optical properties and the life time of clouds in the region. The associated perturbations in radiative balance have a significant impact on the meteorological parameters and this in turn determines the precipitation forming process. Therefore, any change in weather which disturbs the normal hydrological pattern is alarming in the socio‐economic point of view. Hence, the main focus of this work is to determine the variation in transport and distribution of aerosols in the region and to understand the interaction of these aerosols with meteorological parameters and cloud properties.
Description:
Department of Atmospheric Sciences,
Cochin University of Science and Technology
Philip,Mathew; Dr.Ravindranatha Menon,N(Cochin University of Science and Technology, August , 1990)
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Abstract:
The present scientific investigation of the effects of copper, mercury and cadmium has focussed on their effects on two commercially important marine bivalve species, Perna indica (brown mussel) and Donax incarnatus (wedge clam), conspicuous representatives of the tropical intertidal areas. The investigation centred around delineating the cause and effects of heavy metal stress, individually and in combination on these species under laboratory conditions. A clear understanding of the cause and effect can be had only if laboratory experiments are conducted employing sub-lethal concentrations of the above toxicants. Therefore, during the course of the investigation, sub-lethal concentrations of copper, mercury and cadmium were employed to assess the concentration dependent effects on survival, ventilation rate, O:N ratio and tissues. The results obtained are compared with the already available information and partitioned in sections to make a meaningful presentation.The thesis is presented in five chapters comprising INTRODUCTION, ACUTE TOXICITY, VENTILATION RATE, OXYGEN : NITROGEN RATIO and HISTOPATHOLOGY. Each chapter has been divided into various sections such as INTRODUCTION, REVIEW OF LITERATURE, MATERIAL AND METHODS, RESULTS and DISCUSSION
Description:
Head, Division of Marine Biology, Microbiology and
Biochemistry, School of Marine Sciences, Cochin University
of Science and Technology
Resmi, E A; Dr.Mohanakumar,K(Cochin University Of Science And Technology, September , 2012)
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Abstract:
The stratospheric warming events are categorized into major and minor
warming depending on the temperature increase in the polar stratosphere.
The warming is called a ‘major’, when the polar temperature increases
poleward from 60 degree latitude and followed by a reversal in the zonal
wind at 10 hPa (~32 Km). Usually major warming events are associated
with the displacement of polar vortex from high to mid latitudes or the
splitting of vortices in to two. The warming is called a "Minor", when the
polar temperature increases more than 25 degree in a period of a week or
less, at any stratospheric level with less intensified easterly wind anomalies. The stratospheric warmings generated during the transition
period of winter to spring are called final warmings. The warming events
observed in the early winter period (November to early December) over
Canadian region are called Canadian warmings. There is strong
interaction between stratosphere and troposphere during SSW period over
high and low latitudes regions.
The thesis consists of 7 chapters
Description:
Department of Atmospheric Sciences, Cochin
University of Science and Technology
Rosily, A V; Dr.Chandramohanakumar, N(Cochin University of Science & Technology, December , 2002)
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Abstract:
Sulphur is a non conservative major element and is the most active species in the redox processes in nature, especially in aquatic environment . The varying oxidative states from-2 to +6 make it possible to enter into many of the biogeochemical processes. Thus the history, present and future of the chemical composition and behaviour of the natural aquatic systems and sediments have footprints of the sulphur chemistry.Mangroves are considered to be the most productive, fishery supportive ecosystem operating in the intertidal regions. The interlinking of the mangroves with the sulphur chemistry is attempted here.
Description:
Department of Chemical Oceanography, Cochin University of Science and Technology
Krishna Kumar,P A; Chandramohanakumar, N(Cochin University of Science and Technology, October , 1999)
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Abstract:
This study focuses on the fractionation and quantification of chlorophenols, the most important and potential pollutant in this category, the distribution and seasonal dynamics of MBAS, phenols and clorophenols and development of a model to describe the chemical reactivity of the estuary are utilizing the dynamics of boron. The CES is highly influenced by various anthropogenic activities like discharge of agricultural, industrial and urban wastes operation of shipyard, oil and other transporting activities, fishing, dredging etc. Seasonal values of MBAS showed high values in the surface water during monsoon compared to premonsoon and postmonsoon. In the Cochin estuary o-chlorophenol and p-chlorophenol showed low values in the surface water compared to bottom water in the northern part of the estuary and higher values in the surface water in the southern part
Akula Raghunadha, Rao; Basil, Mathew(Naval Physical & Oceanographic Laboratory,Defence Research and Development Organisation, 2008)
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Abstract:
In the present study the availability of satellite altimeter sea level data with good spatial and temporal resolution is explored to describe and understand circulation of the tropical Indian Ocean. The derived geostrophic circulations showed large variability in all scales. The seasonal cycle described using monthly climatology generated using 12 years SSH data from 1993 to 2004 revealed several new aspects of tropical Indian Ocean circulation. The interannual variability presented in this study using monthly means of SSH data for 12 years have shown large year-to-year variability. The EOF analysis has shown the influence of several periodic signals in the annual and interannual scales where the relative strengths of the signals also varied from year to year. Since one of the reasons for this kind of variability in circulation is the presence of planetary waves. This study discussed the influence of such waves on circulation by presenting two cases one in the Arabian Sea and other in the Bay of Bengal.
Nowshad, M; Dr.Kuttyamma, V J; Dr.Menon,N R(Cochin University of Science and Technology, January , 1998)
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Abstract:
The present study aims at surveying the coral lagoons of four islands viz.
Kavarathi, Kalpeni, Kadmat and Agathi, which include quantitative survey of the
major benthic forms using Line Intercept Transect (LIT) technique and
hydrographical study of these lagoon waters The distribution of PHC in the
lagoons has also been followed to understand, the effects of introduction of flat
bottomed ferry boats to the islands.From a biological monitoring stand point for the assessment of manmade disturbance of the coral reefs, it IS highly essential to identify faunal assemblages which will contain 'flag-stones' specIes as indicators of such disturbances. Among the known faunal assemblages In coral reefs the most
diverse groups of sensitive species belongs to bryozoan assemblage. Therefore, the
most common species of bryozoans distributed along the atolls and reef flats
were collected and described in this work Along with this, bryozoans
associated with coral from other parts of Indian ocean have also been added so as
to provide a comprehensive picture of the distribution of bryozoans in the coral
reefs.
Description:
Department of Marine Biology, Cochin University of Science and Technology
Liya, Jayalal; Ramachandran, A(Cochin University of Science and Technology, May , 2014)
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Abstract:
The Indian ornamental fish industry is divided into two-the domestic market and the export market. 90% of the freshwater ornamental fish exported from India are wild caught indigenous species. The study formed the criteria and indicators assessing the sustainability of wild caught ornamental fish exported from India. These indicators were then analyzed for their interactions, connections, linkages and relationships using cognitive mapping. The work is first of its kind in the ornamental fisheries
Sanjana, M C; Dr. Balchand, A N(Cochin University of Science and Technology, April 11, 2005)
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Abstract:
The research work which was carried out to Synergic Reactions in the Estuarine Environment leading to Modulation of Aluminium metal during Transport Processes (in Cochin Estuary)Estuaries are considered as sink or source for terrestrial and various anthropogenically generated materials. These include naturally occurring elements Al, Si, Fe or trace inorganics or industrial pollutants of different types. There have been reports on both positive and negative impacts by the introduction of above materials into the ecosystem.This thesis deals with the trace metal Aluminium (Al) whose average concentration (about 8%) in the earths crust is surpassed only by that of Oxygen and Silicon. There can be no doubt that most of the land derived materials reaches the ocean through rivers via estuaries. An important aspect noticed here is that the concentration of dissolved Al is much lower in sea water than in river water.On critically analysing Cochin estuary, for the entire cycles, covering monsoon, postmonsoon and premonsoon, the following salient features are documented as hereunder. Dissolved Al exhibits high and variable trends in Cochin estuary, the influencing parameters being salinity, SPM, pH and dissolved Si. A general profile showed removal in upper/mid estuary followed by regeneration in the mid/lower estuary and further decrease seawards in the southern/northem arms.Distribution appears to be a function of freshwater input, the monsoon season exhibiting very high concentrations throughout the estuary. As the river discharge decreased with the progress of seasons, dissolved Al concentration also decreased, the metal limiting itself to the upper and mid estuary.
Description:
Department of Physical Oceanography,School of Marine Science, Cochin University of Science and Technology
Aleyamma, Saji Varghese; Dr. Kuruvila, Mathew(Cochin University of Science and Technology, May 19, 2005)
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Abstract:
This overall focus of the thesis involves the systematics and biology of fishes of the family hemiramphidae of cochin coast.India is one of the leading fish producing nations in the world with an average annual production of 6.1 million tonnes of fish and shell fish from capture and culture fisheries in 2001 (Ayyappan and Biradar, 2002).Fisheries play a very significant role in the Indian economy by providing employment to nearly 7 million people directly or indirectly, supplying rich protein food and earning valued foreign exchange.Fishes of the family Hemiramphidae are commonly called ‘half beaks‘.In India, studies on hemiramphids commenced with the work of Day (1878,1889) who recorded thirteen species of hemiramphids from the Indian waters.The study area, which is part of Cochin coast is located between Lat.9°28’ and 10° N and Long.76° 13’ and 76° 31 E. Lying parallel to it is an estuary which is commonly called the Cochin backwaters which has a total area of about 200 sq.miles.The study area is subjected to wide variations in salinity from place to place, season and surface to bottom.The Cochin coast and the adjacent back water system of Kerala has a rich and diversified fish fauna. The hemiramphid fishes constitute a minor fishery of this area.The study on the distribution and availability of hemiramphid fishes present in the Cochin coast shows that they evince different patterns of distribution.In the present study it is noticed that fecundity has high correlation with weight than length of the fish.Histological studies revealed that the spermatogenesis in both H. (H) limbatus and H.(H) xanthopterus, consists of spermatogonia, primary spermatocytes secondary, spermatocytes, spermatids and spermatozoa whereas in the oogenesis of both the species.biological study will be useful in implementation of proper measures of conservation and management so that further devastation of the hemiramphids of Cochin Coast can be controlled.
Description:
School of Industrial fisheries, Cochin University of Science and Technology
Venu, S; Dr.Madhusoodana,Kurup B(Cochin University of Science and Technology, September , 2009)
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Abstract:
Reducing fishing pressure in coastal waters is the need of the day in
the Indian marine fisheries sector of the country which is fast changing from a
mere vocational activity to a capital intensive industry. It requires continuous
monitoring of the resource exploitation through a scientifically acceptable
methodology, data on production of each species stock, the number and
characteristics of the fishing gears of the fleet, various biological
characteristics of each stock, the impact of fishing on the environment and the
role of fishery—independent on availability and abundance. Besides this, there
are issues relating to capabilities in stock assessment, taxonomy research,
biodiversity, conservation and fisheries management. Generation of reliable
data base over a fixed time frame, their analysis and interpretation are
necessary before drawing conclusions on the stock size, maximum
sustainable yield, maximum economic yield and to further implement various
fishing regulatory measures. India being a signatory to several treaties and
conventions, is obliged to carry out assessments of the exploited stocks and
manage them at sustainable levels. Besides, the nation is bound by its
obligation of protein food security to people and livelihood security to those
engaged in marine fishing related activities. Also, there are regional
variabilities in fishing technology and fishery resources. All these make it
mandatory for India to continue and strengthen its marine capture fisheries
research in general and deep sea fisheries in particular. Against this
background, an attempt is made to strengthen the deep sea fish biodiversity
and also to generate data on the distribution, abundance, catch per unit effort
of fishery resources available beyond 200 m in the EEZ of southwest coast ofIndia and also unravel some of the aspects of life history traits of potentially
important non conventional fish species inhabiting in the depth beyond 200 m.
This study was carried out as part of the Project on Stock Assessment
and Biology of Deep Sea Fishes of Indian EEZ (MoES, Govt. of India).
Description:
School of Industrial Fisheries, Cochin University of Science
and Technology