NOPR Community:

Magnetic susceptibility of black sand concentrates of Krishna district, east coast of India

2016-12-08T10:22:51Z

Title: Magnetic susceptibility of black sand concentrates of Krishna district, east coast of India Authors: Rao, B Nagamalleswara; Kshirasagar, T V S R Abstract: Magnetic susceptibility shows good correlation with fineness, sorting and magnetite content but poor correlation with skewness of the samples. The magnetic susceptibility diminishes in the study region from the river mouth to Manginapudi situated at a distance of 39 km in the north. Page(s): 292-293

Clay minerals and their dispersal in the sediments of Vamsadhara river channel and estuary

2016-12-08T10:20:09Z

Title: Clay minerals and their dispersal in the sediments of Vamsadhara river channel and estuary Authors: Varma, D Deva; Rao, K S R; Rao, A T Abstract: Clay mineral suites in the estuary are characterised by high smectite with varying proportions of illite and kaolinite, whereas the clay minerals in the river channel contain high kaolinite with varying proportions of smectite and illite. Thus, two characteristic clay suites are recorded in the river channel and estuary. The factors of differential settling and flocculation of clay minerals in the estuarine environment have minor or no effects on relative variation of clay minerals in the two different suites from the river channel to estuary. Dispersal variation of kaolinite and smectite dominated zones are the major processes operative in the estuary. Page(s): 289-291

Possible role of estuarine sediments in mitigation of mercury loading in biological systems

2016-12-08T10:17:14Z

Title: Possible role of estuarine sediments in mitigation of mercury loading in biological systems Authors: Joseph, K O Abstract: Concentration of mercury was estimated in samples of water, bottom sediments and fish from Ennore estuary during 1982-83. The uptake of mercury from water by fish is about 400 times. The concentration of Hg in water is 0.0012-mu-g.ml-1 while its level in bottom sediment is 0.6-mu-g.g-1. The higher concentration of Hg in soil substrate is attributable largely to fine particulate organic carbon which is 1.2%. The higher fraction of organic carbon has thus a possible role in binding Hg to soil in larger measure than what it releases to water. Page(s): 286-288

Arsenic content in certain marine brown algae and mangroves from Goa coast

2016-12-08T10:15:00Z

Title: Arsenic content in certain marine brown algae and mangroves from Goa coast Authors: Rao, Ch Kesava; Chinnaraj, S; Inamdar, S N; Untawale, A G Abstract: Arsenic has been estimated in 7 species each of brown algae and mangroves, including different parts of Sargassum cinereun. Arsenic is more concentrated in brown algae [concentration/factor(CF) range 1.5 - 7 x 10(3)] as compared to mangroves (CF < 1). In brown algae organic As is accounted for about 75-90% of total, but in S. cinereum and Sphacelaria furcigera about 50-60% inorganic As is noted. Basal thallus and reproductive organs of S. cinereum have higher concentration of total and organic As than active photosynthetic portions. However, holdfast accumulates lesser As but its organic As is high (80%). Arsenic in younger leaves of mangroves is marginally more (0.23 mg.kg-1 dry wt.) than that of mature and yellow leaves (0.16 mg. kg-1). Page(s): 283-285