तमिलनाडु-पोण्डिचेरी तट की तारली मात्स्यिकी-हाल की विदोहन प्रवणता और कुछ जैविक सूचनाऐं

कृपया पूरा लेखा पढ

Recent exploitation trend of oil sardine along Tamil nadu - Pondicherry coast

The Indian oil sardine SardineUa lorgiceps.though a non-conventional resource of the east coast, supports now a regular fishery of high magnitude especially along Andhra Pradesh and TanJl Nadu - Pondicheny coasts. The estimated annual average landing from east coast during the period 1993-97 was 60.638 tonnes against 46.000 t obtained along west coast thereby showing the potential of this new resource, especially along the southern maritime states of the east coast. It has been observed that the oil sardine catch during 1993-97 increased to more than three fold in Andhra Pradesh from that of the previous five year period 1988-92 while along Tamil Nadu - Pondicheny coast the catch almost doubled and recorded 80% of the total oil sardine production of east coast

Appraisal on the marine fishing craft and gear of the Indian coast

The use of fishing methods varying from simple traps to large trawlers and from hand lines to sophisticated purse seines is a typical feature of marine fisheries in India. The regional and seasonal variation is so vast that the developmental agencies and administrative machinery are often handicapped in deciding priorities on modernizing the traditional tools. A document as attempted here, would form a piece of vital information for the R&D agencies. The traditional gear operated in different regions of the Indian coast are classified based on the mode of operation and an exhaustive listing along with local names is attempted. Besides, contributions to the marine fish production separately by traditional and modern craft are brie flu noted

Observations on a whale shark, Rhincodon typus Smith landed at Tuticorin

Information on whale sharks landed along the coasts of India has not been wanting (Prater, 1941 ; Kulkarni, 1948 ; Chacko and Mathew, 1954; Anon., 1958 ; Kaikini et al., 1959 ; Gopalan, 1962; Silas and Rajagopalan, 1963 and Thomas and Kartha, 1964). Chacko (Chacko and Mathew, op. cit.) reported the sighting of a whale shark, over 7 metres in length, on the pearl bank, ThoUayiram Paar, on 11th December 1953. Silas and Rajagopalan (o/>. cit.) recorded the landing of a female whale shark measuring 5.62 metres in total length on 29th July 1961 at Tuticorin

Trawl fishery potential of the south-east coast of India

Scanty information is available regarding trawl fishery resources of the waters of the South-East coast of India in the Gulf of Mannar. Until the establishment of the Offshore Fishing Station of the Government of India at Tuticorin in 1958, no organisation has conducted trawling alorg scientifc lines for charting the offshore fishing grounds, in order to delineate the distribution of commercially importent fish and prawns in space and time. Since 1959, exploratory trawling by medium-sized trawlers has been mainly conductedin the offshore waters around Tuticorin between latitude 8° 00'-9° 10' N and longitude 77°30'-79° 00'E. The results show that fairly rich fishing grounds exist in this area. The psrer indicates scope for further exploitation of the grounds so far charted

Correlation analysis of lidar derived optical parameters for investigations on thin cirrus features at a tropical station Gadanki(13.5ºN and 79.2ºE), India

9-19The optical characterization of thin cirrus clouds is very important to understand its radiative effects. The optical parameters of cirrus clouds namely extinction (), Optical depth () and Linear depolarization ratio (LDR), have been derived from lidar data, obtained from a ground based polarization lidar at a tropical station, Gadanki (13.5ºN and 79.2ºE), India. The range dependent Lidar ratio (LR) has been derived by using an in-house developed iterative method. The present study makes an effort to understand the correlation between different optical parameters, and to get an insight in to the structure, composition and stability of the topical cirrus clouds. The variation of LR values with LDR gives an idea about the nature of aerosol content present within the cloud. It has been observed that there is a negative correlation between LDR and LR with a second degree polynomial fit for thin cirrus cloud conditions. The correlation between ice water content (IWC) derived directly from extinction value and LDR has been found to be positive and it has been used to establish cloud phase accurately instead of from the LDR value itself. From the time series observation it has been also found that the extinction and hence the IWC increases due to the growth of cirrus particle

Macro-physical, optical and radiative properties of tropical cirrus clouds and its temperature dependence at Gadanki (13.5° N, 79.2° E) observed by ground based lidar

The macro-physical and optical properties of cirrus clouds and its temperature dependencies have been investigated at the National Atmospheric Research Laboratory (NARL; 13.5° N, 79.2° E), Gadanki, Andhra Pradesh, India; an inland tropical station during the period of observation January to December 2009 using a ground based pulsed monostatic lidar system data and radiosonde measurements. Based on the analysis of measurements the cirrus macrophysical properties such as occurrence height, mid cloud temperature, cloud geometrical thickness, and optical properties such as extinction coefficient, optical depth, depolarization ratio and lidar ratio have been determined. The variation of cirrus macrophysical and optical properties with mid cloud temperature have also been studied. The cirrus clouds mean height has been generally observed in the range of 9-17 km with a peak occurrence at 13-14 km. The cirrus mid cloud temperatures were in the range from -81 °C to -46 °C. The cirrus geometrical thickness ranges from 0.9-4.5 km and 56% of cirrus occurrences have thickness 1.0 -2.7 km. The monthly cirrus optical depth ranges from 0.01-0.47, but most (>80%) of the cirrus have values less than 0.1. The monthly mean cirrus extinction ranges from 2.8E-06 to 8E-05 and depolarization ratio and lidar ratio varies from 0.13 to 0.77 and 2 to 52 respectively. The temperature and thickness dependencies on cirrus optical properties have also been studied. A maximum cirrus geometrical thickness of 4.5 km is found at temperatures around – 46 °C with an indication that optical depth increases with increasing thickness and mid cloud temperature. The cloud radiative properties such as outgoing long-wave radiation (OLR) flux and cirrus IR forcing are studied. OLR flux during the cirrus occurrence days ranged from 348-456 W/m2 with a low value in the monsoon period. The cirrus IR forcing varied from 3.13 – 110.54 W/m2 and shows a peak at monsoon period

Appraisal of the Marine Fisheries of Kerala

Kerala, the southwestern part of the peninsular India, has a narrow stretch of land with a long surf-beaten coast on the western side and a lush green mountain range on the eastern side. The coastline is 590 km long, which is almost one-tenth of the Indian coastline. Marine fishing, using artisanal tackles like boat-seines, shore-seines and Chinese dip nets, is an age-old tradition of the state. Mechanisation was started in late fifties by the Indo-Norwegian Project, at first in the Quilon area. The early sixties too saw an important technological development, namely the shift from cotton to nylon nets. By mid-sixties, individual entrepreneures entered the scene, paving way for a fast development of trawl fishery in the coastal waters. Commercial purse-seining started during late seventies, and the process of large-scale motorisation of country crafts began in early eighties

Not Available

Not AvailableInformation on whale sharks landed along the coasts of India has not been wanting (Prater, 1941 ; Kulkarni, 1948 ; Chacko and Mathew, 1954; Anon., 1958 ; Kaikini et al., 1959 ; Gopalan, 1962; Silas and Rajagopalan, 1963 and Thomas and Kartha, 1964). Chacko (Chacko and Mathew, op. cit.) reported the sighting of a whale shark, over 7 metres in length, on the pearl bank, ThoUayiram Paar, on 11th December 1953. Silas and Rajagopalan (o/>. cit.) recorded the landing of a female whale shark measuring 5.62 metres in total length on 29th July 1961 at Tuticorin.Not Availabl