202 research outputs found
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)
- …