http://nopr.niscair.res.in/handle/123456789/10644 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/10682 Title: Study on the Distribution and Bioaccumulation of Natural Radionuclides, ²¹⁰Po and ²¹⁰Pb in Parangipettai Coast, South East Coast of India <br/> <br/>Authors: Raja, P; Hameed, P.Shahul <br/> <br/>Abstract: Water, sediment and Biota (plankton, seaweeds, prawn, crabs, gastropods, bivalves and fish) samples collected from the study region were subjected to analyses of&nbsp; ²¹⁰Po and ²¹⁰Pb. It showed non-uniform distribution of these radionuclides in the biota, in a descending order: molluscs &gt; crustaceans &gt; fishes. Concentration of ²¹⁰Po and ²¹⁰Pb were 1.65 mBq/l and 3.38 mBq/l in water samples and 4.38 Bq/kg and 2.31 Bq/kg in sediment samples respectively. Soft tissues and muscle of animals accumulated higher level of ²¹⁰Po while shells and bones contained more ²¹⁰Pb. Bivalve mollusc <i>Perna viridis</i> accumulated higher levels of both ²¹⁰Po and ²¹⁰Pb thus suggesting that this species can serve as a bioindicator in marine environment. Concentration factor of ²¹⁰Po for the biotic components ranged from ~ 10³ to ~10⁴while for ²¹⁰Pb it ranged from ~ 10² to ~ 10³. <br/> <br/>Page(s): 449-455 http://nopr.niscair.res.in/handle/123456789/10681 Title: Community structure of net phytoplankton along surf zone of Mangalore during southwest monsoon season <br/> <br/>Authors: Raveesha, K. P; Mohan, A; Chethan, N; Katti, R. J; Reddy, H.R.V <br/> <br/>Abstract: Data collected from surf waters of Mangalore revealed the time scale variation of hydrographical parameters and phytoplankton community. Salinity and plant nutrients specially nitrate and silicate exhibited a conspicuous fluctuation in relation to intensity of precipitation. Surf water was characterized with much higher levels of limiting nutrients than the Redfield ratio. Diatoms dominated numerically among phytoplankton in the surf waters followed by dinoflagellates and blue green algae. Lower salinity associated with high load of nutrients favored the growth of bloom forming centric types of diatoms. While diverse forms of diatoms, dinoflagellates and blue green algae occurred with increasing salinity in surf waters. Shannon’s species diversity varied from 0.049 to 2.125 and Shannon’s evenness index varied from 0.020 to 0.735. Diversity indices indicated gradual increase in diversity and evenness values in relation to variation of salinity and nutrients <br/> <br/>Page(s): 445-448 http://nopr.niscair.res.in/handle/123456789/10680 Title: Faecal indicators and sanitary water quality of shellfish-harvesting environment: influences of seasonal monsoon and river-runoff <br/> <br/>Authors: Sasikumar, Geetha; Krishnamoorthy, M <br/> <br/>Abstract: Incidence of faecal coliforms in shellfish harvesting areas of the southern coastal district of Karnataka was examined for evaluating the sanitary quality in relation to the seasonal monsoon and river-runoff. Faecal coliforms (FC) counts in seawater, mussel tissue and sediments were highest in monsoon. Geometric mean for FC in sea water was below 14 MPN/100 ml, standard set for “approved area” under NSSP classification during fishing season, but the 90^th percentile were higher. The tissue<i style=""> E. coli</i> levels complied with the EC Directive standard under the “category A”, during mussel fishing season commencing in October in the two mussel beds. MPN FC levels were strongly influenced by the seasonal variations in precipitation and river runoff. During the fishing seasons in pre-monsoon and post-monsoon months, the levels were below the limits <br/> <br/>Page(s): 434-444 http://nopr.niscair.res.in/handle/123456789/10679 Title: Seasonal variation of enzyme activity and stress metabolites in eight benthic macro algae with fluctuations in salinity of Sunderban estuary, India <br/> <br/>Authors: Chakraborty, S; Santra, S C; Bhattacharya, T <br/> <br/>Abstract: Seasonal variation of polyphenols, ascorbic acid, carotenoids and enzymes like catalase, peroxidase and acid phosphatase activities of eight marine benthic algae from the tropical mangrove ecosystem of Sunderban with respect to salinity fluctuations had been examined. Average salinity regimes of estuarine water of the ecosystem were 22.47 ± 2.7 ppt, 12.20 ± 2.5 ppt and 16.00 ± 0.8ppt in Pre-monsoon, Monsoon and Post-monsoon respectively. All the algal forms showed considerable variation in their enzymatic activity concentration as well as stress metabolites with respect to changes in salinity pattern. There was consistent decline in acid phosphatase activity in low saline condition. Ascorbic acid ranged between 0.12 mg 100 g^-1 and 0.41 mg 100 g^-1. Concentration of phenol varied within 3.92 to 19.96%. Carotenoid content was found between 31.06 <img src='/image/spc_char/micro.gif' border=0> gg^-1 and 17.36 <img src='/image/spc_char/micro.gif' border=0> gg^-1. Present study elucidates the role of the antioxidant systems of the algae to combat saline stress in natural conditions <br/> <br/>Page(s): 429-433