SP Biswas - Academia.edu (original) (raw)

Papers by SP Biswas

List of papers on hydrobiology and fisheries published by Prof S P Biswas and co-workers in last ... more List of papers on hydrobiology and fisheries published by Prof S P Biswas and co-workers in last 35 years

Microscopy (Oxford, England), 2015

Scanning electron microscopy has been identified as an important approach in studying scale micro... more Scanning electron microscopy has been identified as an important approach in studying scale microstructures in fish with reference to taxonomy. In this article, a detailed microstructural analysis of the scales of Channa barca, a poorly known snakehead fish was carried out the location of focus, inter-radial distance, average width and inter-circular space of anterior circulii; inter-circular distance and dentition in lateral circulii; the shape, spacing, length of lepidonts in anterior circulii and the number and width of radii were compared with those of a related species, Channa aurantimaculata. The location of the focus was found to be similar to those of the gachua group of the genus Channa but was different from those of the marulius group. There were major similarities-though with a few notable differences-in scale microstructures between C. barca and the aforementioned closely related species C. aurantimaculata, indicating that scale microstructure analysis has the potential...

Microscopy and Microanalysis, 2014

Scanning electron microscopy (SEM) of scales in six species of the fish genus Channa revealed cer... more Scanning electron microscopy (SEM) of scales in six species of the fish genus Channa revealed certain features relevant to taxonomic significance. The location of focus, inter-radial distance and width of circuli, intercircular space, width of radii, shape and size of lepidonts, etc. were found to be different in different species. The importance of SEM of scales in poorly understood taxonomy and phylogeny of the fish genus Channa is discussed with the help of relevant literature. Further, the role of SEM of fish scales for taxonomic applications is discussed in detail.

Transactions - Indian Ceramic Society

Niobates and tantalates are very important ferroelectric materials. Of these, the lithium compoun... more Niobates and tantalates are very important ferroelectric materials. Of these, the lithium compounds are particularly well-known because of their wide ranging high technology applications in communication systems, information storage and processing systems etc. The conventional method of synthesis of niobates and tantalates involves solid state reaction of lithium hydroxide/carbonate with niobium pentoxide/tantalum pentoxide over extended time periods coupled with intermittent grinding and reheating. Of late, microwave heating has come into increasing prominence as an attractive method to reduce the reaction time and minimize energy consumption. In the present work, the conditions for microwave assisted synthesis of lithium niobate and tantalate were standardized and the synthesis of these compounds was achieved in drastically reduced time period without involving repeated grinding and heating treatment. The single phase nature of the synthesized compounds was confirmed by XRD and IR...

Certain aspects of the reproductive biology of O. mossambicus (Peters) from a domestic pond of As... more Certain aspects of the reproductive biology of O. mossambicus (Peters) from a domestic pond of Assam have been described. Morpho-histological studies of the gonad revealed the existence of six maturity stages in O. mossambicus while gonadosomatic index (GSR) indicated that the breeding season extended from March to October. The frequency four polygon of ova diameter showed peaks suggesting four times

Ecology, Environment and Conservation

Journal of environmental biology / Academy of Environmental Biology, India, 2011

The one-stripe spiny eel, Macrognathus aral (Bloch and Schneider), has been gaining importance no... more The one-stripe spiny eel, Macrognathus aral (Bloch and Schneider), has been gaining importance not only as a food fish but also as an aquarium fish for its body shape and behaviour. The overall M:F ratio recorded 1:0.27, both the males and females were mostly mature in May-August. The peak values of gonado somatic ratio (GSR) attained during May for males (1.3) and August forfemales (12.4) indicating that the fish have only one breeding season during summer. The range of ova diameter was found to vary from 0.3 to 1.4 mm, the absolute fecundity ranged from 250 (21.6 cm/27.4 g) to 5220.1 (27.2 cm/66.3 g) while relative fecundity ranged from 9.1 to 128.9. The 50% maturity is attained in length group of 10.1-14 cm for males and 14.1-18 cm for females. The species is a moderately fecund, isochronal spawner and having a restricted breeding season. The relationship between fecundity and body weight and length has also been discussed.

The Environmentalist, 2012

Abstract The Ganges River dolphin (Platanista gangetica Roxburgh) of Subansiri River may be in gr... more Abstract The Ganges River dolphin (Platanista gangetica Roxburgh) of Subansiri River may be in great danger of extinction due to the construction of the 2,000-MW Lower Subansiri Hydroelectric Project, which started in 2006. A recent survey indicates that there are now ...

Journal of Applied Aquaculture, 2012

The Pabdah catfish, Ompok pabda, was successfully spawned with the synthetic hormone Ovatide at t... more The Pabdah catfish, Ompok pabda, was successfully spawned with the synthetic hormone Ovatide at two different doses (0.4 and 0.6 ml/kg of body weight of female). The latency period was 9–10 h at 0.6 ml compared to 10–12 h at 0.4 ml kg of body weight. All the females spawned successfully. Average rate of fertilization (75.5 %) and hatching (60.5%)

Ecological Engineering, 2000

The northeastern Himalayan region is identified as one of the richest regions of the world in bio... more The northeastern Himalayan region is identified as one of the richest regions of the world in bio-diversity. Being in a heavy rainfall zone and also blessed with innumerable snowfed streams and rivers, the region is well-known for fish diversity especially for ornamental fish. The hill streams have poor but distinctive fish fauna, while the floodplain rivers of the region harbour over two hundred species of fish and other aquatic fauna, including the endangered freshwater dolphin, Platanista gangetica. The beels, or the floodplain lakes, are ideal habitats for air-breathing fish and they also act as feeding and breeding grounds for riverine fish during monsoon months. The present communication highlights the hydrobiological features and the ichthyofauna of certain selected water bodies of the northeastern Himalayas with special reference to the Brahmaputra River. : S 0 9 2 5 -8 5 7 4 ( 0 0 ) 0 0 0 7 5 -6

The Environmentalist, 2002

... Very few studies have been made on the ecology in relation to the fisheries of the river sys-... more ... Very few studies have been made on the ecology in relation to the fisheries of the river sys-tem (Singh et al., 1988; Biswas and Michael, 1992; Yadava ... Dr Sanchita Boruah is an Assistant Professor of Zoology at DHSK College, Dibrugarh (e-mail: sanchitaboruah@hotmail.com). ...

A model experiment on soil conservation utilising the plantation of certain herbaceous plants in ... more A model experiment on soil conservation utilising the plantation of certain herbaceous plants in a selected stretch of Majuli, the largest riverine island in the world, was carried out. The plantation followed work to establish the proper inclination for the river bank. The soil erosion in the experimental site was reduced to only about 2% compared with about 15᎐20% in the previous years. All the four species selected for the present study had excellent soil binding capacity and were thus helpful in stabilizing the highly vulnerable soil in the flood plain areas of the region.

Hydrobiologia, 2000

There are nearly 200 species of aquatic vertebrates, almost exclusively fishes, in the Brahmaputr... more There are nearly 200 species of aquatic vertebrates, almost exclusively fishes, in the Brahmaputra River System. This faunal composition includes not only a wide variety of food-fishes, but also about 50 varieties of aquarium fishes. The most spectacular animal in the Brahmaputra is undoubtedly the river dolphin, Platanista gangetica. The population of many species, particularly of the dolphin, is in steady decline. River dolphins, mostly juveniles, often entangle themselves in gill and drift nets, while feeding on trapped fishes. Proper implementation of Indian Fisheries Act, especially a total ban on destructive nets and on killing of brooders and juveniles by explosives and poisoning should be strictly implemented. Poor communication facilities in remote riverbank areas and lack of funds are two important reasons for the slow progress of the conservation of river dolphin and this endangered species is now on the verge of extinction. The anthropogenic activities and their impact on the habitat of river dolphin are discussed.

Studies on the age and growth of two species of carp, Labeo pangusia (Ham.) and L. dero (Ham.). J... more Studies on the age and growth of two species of carp, Labeo pangusia (Ham.) and L. dero (Ham.). J. Bio. Res., 2(2): 116-125. 2 S. P. Biswas, S. A. K. Nasar & K. Chatterjee (1984): Inter-and Intraspecific comparisons on some aspects of the reproductive biology of the carp, Labeo pangusia (Ham.) and L. dero (Ham.). Arch Biol., (Bruxelles) 95 : 11-27. 3 S. P. Biswas (1993): Bionomics of Labeo pangusia (Ham.) from the Highlands of North-East India.