Macrobenthos of Minicoy Island, Lakshadweep

In this present study macro benthos of minicoy island lakshadweep, an attempt has been made to study the distribution and community structure of benthos at different ecosystems. The main objectives of the study include the identification of benthic fauna, their distribution and composition, standing stock, qualitative and quantitative nature in relation to hydrography,seasons and sediment texture, community structure analysis and tropic relationships. This base line study at Minicoy,thus establishes that the benthos of sea grass and mangrove ecosystems(nursery grounds) determines the richness and diversity of demersal fish fauna at the nearby lagoon and reef areas to a great extent. Any serious stress on these ecosystems may lead to disappearance of certain fish species in the nearby future

Studies on the macrobenthic community of Cochin backwaters with special reference to culture of Eriopisa chilkensis (Gammaridae-Amphipoda)

This thesis Entitled studies on the macrobenthic community of cochin backwaters with special reference to culture of eriopisa chilkensis (Gammaridae- amphipoda).Benthic organisms are usually studied for environmental impact assessment, pollution control and resource conservation. The benthic monitoring component has three major objectives: 1) characterize the benthic communities to assess the estuarine health, 2) determine seasonal and spatial variability in benthic communities, and 3) detect changes in the estuarine community through examination of changes in abundances of specific indicator taxa and other standard benthic indices.Cochin backwaters situated at the tip of the northern Vembanad lake is a tropical positive estuarine system. The backwaters of Kerala support as much biological productivity and diversity as tropical rain forest and are responsible for the rich fishery potential of Kerala. Backwaters also act as nursery grounds for commercially important prawns and fishes.The thesis has been subdivided into seven chapters. The first chapter gives a general introduction about the topic and also highlights the scope and purpose of the study. The second chapter covers the methodology adopted for the collection and analysis of water quality parameters, sediment and the macrobenthic fauna.Chapter 3 deals with hydrographic features, sediment characteristics and the spatial variation and abundance of macrobenthic fauna in the Cochin estuary.Chapter 4 explains the impact of organic enrichment on macrobenthic popUlation in the Cochin estuary and includes the comparison of the present data with the earlier work in this region.Chapter 5 deals with seasonal variability in abundance of macrobenthic species in the estuary. The study was conducted from 9 stations during three seasons (pre-monsoon, monsoon and post-monsoon) in 2003.Chapter 6 deals with Life history and Population Dynamics of Eriopisa chilkensis Chilton (Gammaridae-Amphipoda). The life cycle of the gammarid amphipod Eriopisa chilkensis from the Cochin estuary, south west coast of India was studied for the first time under laboratory conditions.

Application of Biofloc Technology (BFT) in the nursery rearing and farming of giant freshwater prawn, Macrobrachium rosenbergii (deMan)

In India a study conducted by CIFE and CIBA (1997), concluded that shrimp farming does more good than harm and it is not eco-unfriendly (Krishnan and Birthal, 2002). Upsurge in coastal aquaculture activity induced by high profitability is reported to have caused adverse impacts on coastal ecosystems and social environments (Parthasarathy and Nirmala, 2000). The crustacean farming sector has received criticism for excessive use of formulated feed containing high protein, of which around 50% gets accumulated at the pond bottom as unconsumed (Avnimelech, 1999; Hari et al., 2004, 2006). The wasted feeds undergo the process of degradation and results in the release of toxic metabolites to the culture system. Reduction of protein in the feed, manipulation and utilisation of natural food in the culture system are the remedy for the above problems. But before reducing the feed protein, it should be confirmed that the feed with reduced protein is not affecting the growth and health of the cultured animal. In the present study, biofloc technology is identified as one of the innovative technologies for ensuring the ecological and environmental Sustainability and examines the compatibility of BFT for the sustainable aquaculture of giant prawn, M. rosenbergii. This thesis starts with a general introduction (Chapter-1), a brief review of the most relevant literature (Chapter-2), results of various experiments (Chapter-3-6), summary (Chapter-7) and recommendations and future research perspectives in the field of biofloc based aquaculture (Chapter – 8). The major objectives of this thesis are, to improve the ecological and economical sustainability of prawn farming by the applicationof BFT and to improve the nutrient utilisation in aquaculture systems.

Studies on the effect of pollution, with special reference to benthos, in Cochin backwaters

Considerable number of factories and related establishments forming an industrial complex are located in the upper reaches of the estuary from Varapuzha about 10km from cochin barmouth to Alwaye while lower down are the retting grounds at Vaduthala and nearby places at about 5km from the barmouth. Muncipal wastes from the city population of over 5 lakhs effluents and solid waste from several fish processing factories and other land washings around Willington island reach the estuary move near its lower reaches close to the barmouth. Cochin estuary is the biggest in the state providing water front for the largest number of industries from the small retting grounds of Vaduthala to the huge fertilizer factories of Udyogamandal and receiving the highest quantity of town sewage and land drainage. The estuary contributes itself as nursery ground for shrimps and related fishery as well. Study of this estuary therefore contributes to a typical environment as regards to pollution problems in the tropics and hence the scope of the present investigation

Studies on diseases of bamboos and nursery management of rhizoctonia web bligi-it in kerala

Bamboos are vulnerable to various diseases which affect them in nurseries, plantations as well as in natural stands. In India, rot and blight of emerging culms have already been identified as the limiting factor of the bamboo production in many bamboo growing areas, especially in the coastal belts of Orissa (Jamaluddin et a1., 1992). Similarly, foliage blight and rust have been recorded to pose threat to nursery as well as outplanted seedlings which are in the early establishnent phase (Bakshi et a1., 1972; Harsh et a1., 1989). With the increased emphasis and priority on raising multipurpose tree species, large—scale planting of bamboos has been initiated recently in the State. Limited experience in raising the bamboo seedlings together with the lack of information on bamboo diseases and their control measures often resulted in partial to complete failure of many nurseries. Also, poor handling of bareroot seedlings for outplanting affected seriously the planting programme. This was clearly reflected by the large-scale nortality of outplanted young seedlings reported from many plantations. So far, no systanatic attempt has been made to study the diseases affecting bamboos in nurseries, plantations and natural stands in the country. Hence, the present investigation was taken up to conduct a systematic study of the diseases affecting bamboos in Kerala.

Hydrogeochemical evaluation of inorganics and bioorganics in selected aquatic environments

The present study is an investigation to address relevant chemical aspects of the three varied aquatic environments, such as mangroves, river and the estuary. The sampling locations include a thick mangrove forest with high tidal activity, a mangrove nursery with minimal disturbances and low tidal inundation, a highly polluted riverine system and an estuarine site, as reference. Nutrients and bioorganic compounds in the water column and surface sediment were estimated in an attempt to understand the regeneration properties of these different aquatic systems.Assessment of the trace metal pollution was also carried out.

Studies on the Effects of Bottom Trawling on the Benthic Fauna off Veraval Coast, Gujarat

Bottom trawling is one among the most destructive human induced physical disturbances inflicted to seabed and its living communities. The bottom trawls are designed to tow along the sea floor, which on its operation indiscriminately smashes everything on their way crushing, killing, burying and exposing to predators the benthic fauna. Bottom trawling causes physical and biological damages that are irreversible, extensive and long lasting. The commercial trawling fleet of India consists of 29,241 small and medium-fishing boats. The northwest coast of India has the largest fishing fleet consisting of 23,618 mechanized vessels, especially the bottom trawlers. However, attempts were not made to study the impact of bottom trawling along Northwest coast of India. The estimated optimum fleet size of Gujarat is 1,473 mechanised trawlers while 7402 commercial trawlers are operated from the coast of Gujarat. Veraval port was designed initially for 1,200 fishing trawlers but 2793 trawlers are being operated from this port making it the largest trawler port of Gujarat. The aim of this study was to investigate the effects of bottom trawling on the substratum and the associated benthic communities of commercial trawling grounds of Veraval coast. The study compared the differences between the samples collected before and after experimental trawling to detect the impacts of bottom trawling. Attempts were made to assess the possible impact of bottom trawling on:(i) the sediment characteristics (ii)the sediment heavy metals (iii) epifauna (iv) macrobenthos and (v) meiobenthos. This study is expected to generate information on trawling impacts of the studied area that will help in better management of the biological diversity and integrity of the benthic fauna off Veraval coast. An exhaustive review on the studies conducted around the world and in India on impact of bottom trawling on the benthic fauna is also detailed.In the present study, the bottom trawling induced variations on sediment organic matter, epifauna, macrobenthos and meiobenthos were evident. It was also observed that the seasonal/ natural variations were more prominent masking the trawling effect on sediment texture and heavy metals. Enforcement of control of excess bottom trawlers and popularization of semi pelagic trawls designed to operate a little distance above the sea bottom for off bottom resources will minimize disturbance on the sea bottom. Training and creating awareness in responsible fishing should be made mandatory requirements, to the coastal communities. They should be made wardens to protect the valuable resources for the benefit of sustainability. To protect the biodiversity and ecosystem health, the imminent need is to survey and make catalogue, identification of sensitive areas or hot spots and to adopt management strategies for the conservation and biodiversity protection of benthic fauna. The present study is a pioneering work carried out along Veraval coast. This thesis will provide a major fillip to the studies on impact of bottom trawling on the benthic fauna along the coast of India.

Population Characteristics of Prawns in Natural and Selective Stocking System

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.

Studies on the macrobenthos of mudbanks of Southwest cost of India

The present study was undsrtaken.with the objectives to assess the distribution and density of population of benthic animals with special reference to macrofauna from the south west coast of India from ' Malippursa 1 in the north to Alleppey in the south, to evaluate significant difference, if any, in the number and distribution of animals in th md bank regions and other intermittent stations, to examine the influence of bottom stability on the distribution of fauna, to observe the effect of the environmental parameters on the distribution pattern of nacrofauna, and to evaluate the nature and depthpwise distribution of the benthic fishery. The region selected for the investigation is one of the nest important fishing grounds in India for bottom fishing especially for prawns, covering a distance of about 60 kns in length.total number of thirty stations in five transects at right angles to the coast, each consisting of six stations were surveyed. The six stations in a transect were at depths of 5 m, 10m, 20:, 30:, 35m and 45m respectively formation of the Iudbanke, popularly known as 'Ghaknra' in the local language, is a peculiar phenomenon along the ooaet of Kerala and provides a good fishing ground.quantitative distribution of the mecrofauna chewed that the maximum number of organism was near the 35 n contour line in the first three profiles whereas in the fourth and fifth profiles it was at 20 n and 30 m depth respectively. The density of the fauna wee comparatively poor in shallow water etatione at depths 5-‘IO M.was a general decline in the numerical abundance and biomass of the bottom fauna in all the stations during the monsoon period. There has been very little yearly change in the composition of the fauna during the two years‘ study.

Apptication of Biofloc Technology (BFI) in Ihe nunery rearing and farming of giant freshwater prawn, Macrobrachillm rosenbergii (de Man)

This thesis Entitled Application of Biofloc technology (BFT) In the Nursery Rearing and Farming of Giant Freshwater Prawn,Macrobrachium Rosenbergii(De Man). Aquaculture, rearing plants and animals under controlled conditions is growing with an annual growth rate of 8.3% in the period 1970-2008 (FAO, 2010). This trend of growth is essential for the supply of protein-rich food for ever increasing world population. But growth and development of aquaculture should be in sustainable manner, preferably without jeopardizing the aquatic environment.In the present study, the application of BFT in the nursery rearing and farming ofgiant freshwater prawn, M. rosenbergii, is attempted. The result of the study is organised into eight chapters. In the first chapter, the subject is adequately introduced. Various types of aquaculture practices followed, development and status of Indian aquaculture, present status of freshwater pravm culture, BF T and its use for the sustainable aquaculture systems, theory of BFT based aquaculture practices, hypothesis, objective and outline of the thesis are described. An extensive review of literature on studies carried out so far on biofloc based aquaculture are given in chapter 2. The third chapter deals with the application of BFT in the primary nursery phase of freshwater prawn. Several workers suggested the need for an intermediate nursery phase in the culture system of freshwater prawn for the successful production. Thirty day experiment was conducted to study the effect of BFT on the water quality, and animal welfare under the various stocking densities. The study concluded that stocking finfishes in biofloc-based monoculture system of freshwater prawns has the potential of increasing total yield. Prawns having a higher commercial value than finfishes besides ensuring economic sustainability. Results showed that prawn yield and survival was better in catla dominated tanks. Based on the results of the study, it is recommended to incorporate 25% rohu and 75% catla in the biofloc-based culture system of giant freshwater prawns. The results of the present study also recommend to stock relatively larger catla for biofloc-based culture system. Fish production was also higher in the 100% catla tank. When catla was added in higher percentages it should ensured that the hiding objects in the culture ponds shall be used in order to reduce the chance of cannibalism among prawns. rohu and catla equally have the ability to harvest the biofloc, catla consumes the planktonic contributes in the floc whereas rohu grazed on the bacterial consortium suspended in the water column. In Chapter 8, recommendations and future research perspectives in the field of biofloc based aquaculture is presented.

Spray Pyrolysed Tin Chalcogenide Thin Films: Optimization of optoelectronic properties of SnS for possible photovoltaic application as an absorber layer

In the early 19th century, industrial revolution was fuelled mainly by the development of machine based manufacturing and the increased use of coal. Later on, the focal point shifted to oil, thanks to the mass-production technology, ease of transport/storage and also the (less) environmental issues in comparison with the coal!! By the dawn of 21st century, due to the depletion of oil reserves and pollution resulting from heavy usage of oil the demand for clean energy was on the rising edge. This ever growing demand has propelled research on photovoltaics which has emerged successful and is currently being looked up to as the only solace for meeting our present day energy requirements. The proven PV technology on commercial scale is based on silicon but the recent boom in the demand for photovoltaic modules has in turn created a shortage in supply of silicon. Also the technology is still not accessible to common man. This has onset the research and development work on moderately efficient, eco-friendly and low cost photovoltaic devices (solar cells). Thin film photovoltaic modules have made a breakthrough entry in the PV market on these grounds. Thin films have the potential to revolutionize the present cost structure of solar cells by eliminating the use of the expensive silicon wafers that alone accounts for above 50% of total module manufacturing cost.Well developed thin film photovoltaic technologies are based on amorphous silicon, CdTe and CuInSe2. However the cell fabrication process using amorphous silicon requires handling of very toxic gases (like phosphene, silane and borane) and costly technologies for cell fabrication. In the case of other materials too, there are difficulties like maintaining stoichiometry (especially in large area films), alleged environmental hazards and high cost of indium. Hence there is an urgent need for the development of materials that are easy to prepare, eco-friendly and available in abundance. The work presented in this thesis is an attempt towards the development of a cost-effective, eco-friendly material for thin film solar cells using simple economically viable technique. Sn-based window and absorber layers deposited using Chemical Spray Pyrolysis (CSP) technique have been chosen for the purpose

Nutritional Requirements Of The Fry Of Gold-Spot Mullet Liza Parsa (Hamilton)

Most tropical aquatic environments are naturally fertile and their natural fertility is renewed very rapidly. Natural food for many cultivable organisms can be grown to the maximum by proper management. However, enrichment of the environment can be done through rational fertilization. Still further increase in stocking rates, can yield increased crop if adequate feeding is done. Thus fish and shellfish nutrition is an important aspect of the multidisciplinary subject of aquaculture. The oldest and most classical studies in physiology have investigated the nutritional needs of the species of interest to aquaculture. The alimentary requirements for proteins, lipids, mineral salts and vitamins have been established for some temperate species. But, the nutritional requirements of only few tropical species have been studied. Before formulating a diet, a thorough knowledge of the nutrient requirement of the species is essential. It is against this background that the present area of investigation has been identified. "Nutritional requirements of the fry of gold-spot mullet Liza parsia" is a comprehensive attempt to quantify the nutritional factors that are essential for producing healthy fingerlings for stocking the farms. Aspects such as the protein and lipid requirements of the fry, the vitamin essentiality, nutritive evaluation of protein and lipid sources suitable for compounding diets were covered in this research project. The ultimate aim has been to evolve practical diets which could be applied in the nursery phase for juvenile production.

Application of chitosan and PASS for the removal of turbidity and colour from water

The most common and conventional method for removing turbidity from water is by coagulating with alum or iron salts, and settling the precipitate in suitably designed clarifiers followed by filtration. But the sludge produced is bulky, difficult to dewater and accumulates in the dumping grounds causing environmental problems. Synthetic polymers such as polyacrylamide and polyethyleneoxide have been investigated for their ability to remove turbidity. They overcome many of the disadvantages of conventional methods, but are cost—effective only when rapid flocculation and reduction in sludge volume are demanded. Considering the aforementioned situation, it was felt that more easily available and eco-friendly materials must be developed for removing turbidity from water. The results of our studies in this direction are presented in this thesis. The thesis comprises of nine chapters, with a common bibliography at the end. Chapter 1 gives an introduction to the nature of turbidity and colour usually present in water. Chapter 2 discusses the nature and availability of the principal material used in these studies, namely chitosan. Chapters 3 to 8, which deal with the actual experimental work, are further subdivided into (a) introduction, (b) materials and methods, (c) results and discussion and (d) conclusions. Chapter 9 summarises the entire work so as to put the results and conclusions into proper perspective.

Sterols in mangrove sediments of the cochin estuary

The thesis entitled “Sterols in Mangrove Sediments of the Cochin Estuary” is an attempt to characterize the sterol content of the mangrove sediments, their dietary status with respect to the natural flora and fauna present, their transfonnations in the sediment and assess contributions, if any to the nursery character of the mangrove eco system. Samplings were done from two sites at Mangalavanam and Vypin. Mangalavanam is a patchy mangrove area in the heart of the city of Cochin and serves as a small bird sanctuary. This is an almost closed system with a single narrow canal linking to the estuary. Vypin, the largest single stretch of mangroves in Kerala, is regularly inundated by a semi diurnal rhythm of Cochin bar mouth. Perhaps, this is the only site in Kerala where one can see mangroves right along the accreting seacoast. However a lot of developmental pressure is threatening the very existence of these mangroves. Post monsoon sediment samples from these areas were used for the present study, as it is the period of maximum faunal growth and activity

Studies on seed pathology and seedling diseases of some important indigenous tree species of kerala

In forestry, availability of healthy seeds is an important factor in raising planting stock. Initial seed health and storage conditions are the major factors governing the germinability of seeds. Like seeds of agricultural and horticultural crops, forest tree seeds are also liable to be affected by micro-organisms during storage, which affects the germination, and reduces the viability. Further introduction of seed-borne diseases into newly sown crops/areas on account of using unhealthy seeds is also not ruled out. Availability of healthy stock of seedlings is intrinsic for raising plantations and to meet this requirement elimination of nursery diseases by appropriate chemicals is of prime imortance. As exotic tree species may become susceptible to various native pathogens, it is generally considered better to select indigenous tree species for large scale plantations as they are well adapted to local environment. However, before taking up large scale afforestation progranme involving any indigenous tree species, it is essential to have knowledge about seed disorders and seedling diseases and their management. with a View to select appropriate tree species with fewer seed disorders and seedling disease problems for use in further plantation programme, four indigenous tree species such as Albizia odoratissima (L.f) Benth., Lagerstroemia microcazpa Wt., Pterocazpus marsupiwn Roxb. and Xylia xylocarpa (Roxb.) Taub. were evaluated to meet the above parameters