Carbon dioxide and water vapour characteristics on the west coast of Arabian Sea during Indian summer monsoon

Carbon dioxide, water vapour, air temperature and wind measurements at 10 Hz sampling rate were carried out over the coast of Arabian Sea, Goa (15°21'N, 73°51'E) in India. These observations were collected, in association with the surface layer turbulent parameters for the Arabian Sea Monsoon Experiment (ARMEX). In the summer monsoon period, concentration of CO 2 was in the range of 550-790 mg m -3 whereas the water vapour was in the range of 17.5-24.5 g m -3. The Fast Fourier Transform (FFT) analysis has been performed on these observations to investigate the spectral behaviour of CO 2 and water vapour. The relation between CO 2 and water vapour on various atmospheric scales has been proposed. CO 2 and water vapour observations confirmed the existence of periodicities of large (11, 8 days), meso (5 days) and micrometeorological (20 min) scales

Larval and juvenile rearing of black-lip pearl oyster, Pinctada margaritifera (Linnaeus)

The black-lip pearl oyster, Pinctada margaritifera (Linnaeus), has been cultured in the experimental shellfish hatchery at Tuticorin, India. The flagellates Isochrysis galbana and Pavlova lutheri were used independently as larval food at a concentration of 5 cells/μl up to day 5 and the ration was doubled thereafter until spat setting. The initial larval density was 1/ml. Straighthinge veliger stage (75×60 μm) was reached in 20 h, umbo stage (140×130 μm) on day 12, pediveliger (220×210 μm) on day 20 and plantigrade (260×240 μm) on day 23, and spat of 350×300 μm appeared on day 28. I. galbana promoted faster growth and early spat setting as compared to P. lutheri. The modal component of the larval population showed an average growth of 10.98 μm/day. A total of 6.3% of the initial larval population metamorphosed as spat. Juveniles cultured in the laboratory showed a growth rate of 0.09 mm/day. On transplantation to the culture raft in the farm, growth rate increased to 0.4 mm/day. The juveniles suffered heavy mortality after 4 months. It remains to be tested whether P. margaritifera juveniles would have a greater chance of survival in oceanic island conditions, as the natural distribution of the species in India is confined to the Andaman and Nicobar Islands

Measurements of carbon dioxide and heat fluxes during monsoon-2011 season over rural site of India by eddy covariance technique

An increase in carbon dioxide (CO2) concentrations in the atmosphere due to anthropogenic activities is responsible for global warming and hence in recent years, CO2 measurement network has expanded globally. In the monsoon season (July-September) of year 2011, we carried out measurements of CO2 and water vapour (H2O) concentrations along with wind and air temperature over a tropical site in southeast India having rural topography. To collect these observations, the instrumentations used were the sonic anemometer for wind and temperature, and the open path H2O/CO2 infrared gas analyzer for CO2 and H2O concentrations. Using these observations, we explored the diurnal variability of CO2 flux along with sensible and latent heat. The CO2 flux was positive during night-time and negative during daytime and in phase with convective instability. The CO2 flux relationships with the meteorological parameters such as wind speed, temperature and heat fluxes have been analysed. The seasonal (monsoon) half hour mean of CO2 flux which was -3.55 μmol m-2 s-1 indicated the experimental site as a CO2 sink region (net seasonal uptake). An increase in CO2 concentrations during weekends was not observed due to unavailability of heavy vehicular traffic

Manual on Pearl Oyster Seed Production, Farming and Pearl Culture

The Central Marine Fisheries Research Institute has developed expertise on various marine fisheries and mariculture technologies over the past several years. Based on this expertise the Institute has been offering regular training courses to officials from State Governments, Universities, ICAR Institutes, Krishi Vigyan Kendras, training institutions, industry and progressive farmers on subjects like marine prawn hatchery, prawn farming, pearl oyster hatchery, pearl oyster culture, pearl culture, edible oyster hatchery, edible oyster farming, seaweed culture and utilisation, SCUBA diving, estimation of marine fish production and stock assessment. The Trainers' Training Centre (TTC) of the CMFRI, Cochin, established in the year 1983, has so far conducted 83 such trainings for 590 personnel from the various maritime states including Pondicherry, Lakshadweep and the Andaman & Nicobar Islands

Pearl production in relation to the graft tissue in the pearl oyster Pinctada fucata (Gould)

This reports the results of study on which region of the mantle gives good quality pearls and also higher production rate. The mantle tissue from 4 areas namely anterior (a),posterior (b), middle (c), and central (d)regions were used. This study showed that the middle region of mantle when used as graft tissue resulted in not only high percentage of pearl formation (50.28%) but also, the marketable pearls (A, B and C - groups) accounted for 77.53% of the total pearls produced

The pearl oysters

An account of the pearl oyster resources with a brief note on biology, collection methods, seed production and conservation and management in the Indian subcontinent is dealt with in this paper. Both in the Gulf of Kutch and the Gulf of Mannar, the population does not show improvement. Conservation and management of this important resource in the light of the present R&D carried out by the CMFRI is discussed. Enhancement of the wild stock through the production of genetically improved seed in the hatchery and ranching them to selected beds and close monitoring of the physico-chemical and biological factors over a period of time is suggested. Farming of oysters on the natural beds can enhance the pearl quality and may form a breeding reserve

Role and acceptability of traditional birth attendants (DAIs) in a rural community in South India

Dais are the traditional birth attendants, conducting deliveries at home in the majority of villages in India. A study was planned to find out the feasibility of utilising the services of the dais in case-finding in Tuberculosis (TB) and for drug delivery to diagnosed patients. As a preliminary step, a survey was done with a view to find out the role and acceptability of the dais by the community in 5% of households in randomly selected 24 of the 48 villages in Sriperumbudur taluk in Tamil Nadu, where a voluntary organisation. "PREPARE" was delivering primary health care through dais. A total of 466 individuals, either the head of the household or any other responsible person available, were interviewed to find out the role and acceptability of the dais by the community. The salient findings of this study are that 83% mentioned that the dais reside in their respective villages. hence the services of the dais were available at ail times and 82 % had stated that the services were useful to them. This background information is essential for health planners so that this task force could be effectively utilised in health programmmes, in the rural areas in India

Influence of wind speed on surface layer stability and turbulent fluxes over southern Indian peninsula station

Surface to atmosphere exchange has received much attention in numerical weather prediction models. This exchange is defined by turbulent parameters such as frictional velocity, drag coefficient and heat fluxes, which have to be derived experimentally from high-frequency observations. High-frequency measurements of wind speed, air temperature and water vapour mixing ratio (eddy covariance measurements), were made during the Integrated Ground Observation Campaign (IGOC) of Cloud Aerosol Interaction and Precipitation Enhancement Experiment (CAIPEEX) at Mahabubnagar, India (16∘44′N, 77∘59′E) in the south-west monsoon season. Using these observations, an attempt was made to investigate the behaviour of the turbulent parameters, mentioned above, with respect to wind speed. We found that the surface layer stability derived from the Monin–Obukhov length scale, is well depicted by the magnitude of wind speed, i.e., the atmospheric boundary layer was under unstable regime for wind speeds >4 m s−1; under stable regime for wind speeds <2 m s−1 and under neutral regime for wind speeds in the range of 2–3 m s−1. All the three stability regimes were mixed for wind speeds 3–4 m s−1. The drag coefficient shows scatter variation with wind speed in stable as well as unstable conditions

Embryonic and early larval development of pearl oyster Pinctada fucata (Gould)

Hatchery production of seed is of great importance in aquaculture, particularly in situations where availability of natural seed is undependable. Besides, the system provides advantages of selective breeding keeping in view the genetic factors. Commercial hatcheries already sustain large-scale production of edible oysters in several countrie

Biofouling, boring and predation of pearl oyster

During the course of the experiments in pearl culture since 1972 in the Gulf of Mannar, several problems were encoimtered in the farm due to biofouling, boring and predation of oyster stocks. An account of fouling and boring organisms in the farm at Veppalodai was given by Alagarswami and Chellam (1976). Nishii (1961) and Nishii et al. (1961) indicated some relationship between the frequency of cleaning and growth of pearls in the Japanese waters. Wada (1973) reported that animals and seaweeds setting on the oysters and baskets inhibited the growth not only of the oysters but also of the pearls. The occurrence of polychaete and sponge borers on the pearl oyster Pinctada fucata and their control measures were given by Velayudhan (1983)