Mangroves and its importance to Fisheries

Mangroves act as a buffer zone between sea and shore, protecting the shore from erosion and also plays a valuable role as a shield from disasters tike cyclone and tsunami. The ecological significance of mangroves in many tropical countries has been qualitatively well documented and recognized. Mangroves are the breeding and nursery grounds fo r many wildlife species including many fishes, crustaceans and mollusc population. Thus the habitat loss of this unique ecosystem has direct repercussions in the fishery of the regio

Present status of mussel farming- Winter School on Recent Advances in Breeding and Larviculture of Marine Finfish and Shellfish

The green mussel (Perna viridis) is also referred as the green lipped mussel or the Asian green mussel. The shell of P.viridis tapers to a sharp, down turned beak and has a periostracum that is dark green to dark brownish green. The ventral margin of the shell is straight or weakly concave. The beak has interlocking teeth, one in the right valve and two in the left. The wavy posterior end of the pallial line and the large kidney-shaped adductor muscle are diagnostic features of this species.The native range of the green mussel is along the Indian coast and throughout the Indo- Pacific. It occurs naturally and is widely distributed along the intertidal coasts of Indi

Harvesting in situ microalgal feed by enriching seawater

Mixed populations of marine natural microalgae were continuously cultured at high density through seawater enrichment with the Walne’s medium, at the marine hatchery complex of Calicut Research Centre of CMFRI. Freshly collected seawater from Konnad beach, decanted after an hour of sedimentation to remove sand and debris, was transferred to big transparent containers. Seawater was enriched with Walne’s medium at the rate of 200 ml solution A, 100 ml solution B and 50 ml of vitamins for 100 l seawater

Mangroves of Kerala

Mangroves plants are salt tolerant plants of tropical and subtropical intertidal regions of the world. These highly adapted plants have many peculiar features than their terrestrial and aquatic counterparts. The word ‘mangrove’ can also be used to describe the habitat as well as the plants. Mangroves are distributed in the tropical countries of the world. The mangrove ecosystem covers only 0,037 per cent of the world's surface or 0.12 per cent of the Earth’s land are

Shellfish poisoning

Certain dinoflagellales, diatoms and cyanobacteria produce biotoxins . These marine toxins are water soluble and heat stable. Shellfishes being filter feeders tend to accumulate these toxins. After consuming such bivalves ingested with toxin bearing planktons, human toxicity and mortality has been reported. While we aim for large scale mariculture o f marine bivalve mollusks, the sanitary conditions in which they grow and their taste quality must be improved and protected. Mariculture sites should be protected from dumping anthropogenic wastes and regular monitoring of water quality is very much essential. Stray numbers of toxin bearing microalgae as normally found in seawater will not be harmful and it becomes when they outbreak and form blooms

Green tide and fish mortality along Calicut coast

Intense greenish brown coloured bloom was noticed in the Arabian Sea along the Calicut coast, on 27.09.2011, which lasted up to 17.10.2011 (Fig. 1). The blooming organism was identified as the “green tide” forming alga, Chattonella marina (Subrahmanyan) Hara & Chihara,1982. Fresh samples when observed under microscope which exhibited active movement aided by flagella and had many bright green disc shaped chromatophores distributed throughout the cell (Fig. 2). The samples when preserved in formalin, formed a jelly like mass

Coal ash utilization in building and agricultural applications

The increasing cause of disposal of coal ash in terms of environmental pollution stresses the urgent need to find its potential uses. In order to use coal ash fruitfully, various experiments have been carried out at RRL, Bhopal in making concrete block, brick, door shutters, etc. But these hardly consume about 5% of the total quantum of ash produced annually in India.Therefore, attempts have been made to utilise the coal ash in bulk quantity for conditioning wasteland, to increase its fertility Coal ash is basically an amorphous ferro-alumino silicate, which is also characteristically high in Ca'+ Mg++ Na' and K+. The impact of coal ash in agriculture and in building application depends on various physico-chemical properties for which multi -disciplinary experiments have been conducted at lab scale in RRL, Bhopal and optimized the process details for pilot scale demonstration. This paper deals with the use of coal ash in agriculture and the process of making construction materials and its properties. Crops, vegetables and cereals had grown and were found that the crop yield increased by coal ash application and there was no toxicity. Coal ashes have been used as filler and natural fibre jute as reinforcement in making polymer composite,which can be used as wood substitute materials. Coal ash addition increased the dimensional stability; hardness, durability, and wear resistance

PI Controller Based New Soft-Switching Boost Converter With A Coupled Inductor

Novel full bridge DC-DC boost converters is mainly used in research applications, where the output voltage is measurably higher than the source voltage. In this project designing of a new topology of a non isolated boost converter with zero voltage switching control technique is discussed. To achieve ZVS condition the auxiliary circuit has a coupled inductor and a diode. The advantages of the ZVS are reverse recovery problem of MOSFET anti parallel body diodes are resolved and also the voltage and current stress on the switch components are reduced. This topology has a light weight and cost less. This technique will reduce the switching losses and improve the efficiency by ZVS technique, but it does not improve the turn-off switching losses by a ZCS technique. In this topology have two operational conditions depending on the situation of the duty cycle. The detailed operating analysis of the proposed converter and the design method of the main circuit are presented. To improve the effectiveness and feasibility of the proposed boost converter PI controller is used. Here microcontroller is used in the proposed topology

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Mussel Farming Technology Dissemination to the Self Help Groups

The study is an attempt to assess the socio-economic impact of mussel farming by mobilising the self-help groups in Kerala snd Karnataka coastal belts. The study showed that mussel farming faced a number of impediments such as water salinity, seed availability, climatic vagaries, problem related to identification of proper beneficiaries and problems in marketing of mussels. The correlational analysis revealed a proportional relatioinship between group dynamics effectiveness and average yield obtained for each self-help group, which ensured a reasonable profit as a consequences of adoption of mussel farming