NOPR Collection:

Effect of thermal stress on spore shedding in some red algae of Visakhapatnam Coast

Tue, 01 Sep 1987 00:00:00 GMT

Title: Effect of thermal stress on spore shedding in some red algae of Visakhapatnam Coast Authors: Kaliaperumal, N; Rao, M Umamaheswara Abstract: Effect of thermal stress on the liberation of tetraspores from Gelidium pusillum (Stackhouse) Le Jolis, Pterocladia heteroplatos (Boergesen) Umamaheswara Rao and Kaliaperumal and Gelidiopsis variabilis (Greville) Schmitz was studied, in response to temperatures lower (0ᵒ -10ᵒC) and higher (40ᵒ -45ᵒC) than the tolerance limits of plants. Spore liberation was seen in these algae exposed to low and high temperatures for short durations but the output decreased with increase in the duration of treatment. The temperature tolerance capacity varied in the algae tested. Page(s): 201-202

Toxic effects of Zn-oil mixture on Perna viridis (L.)

Tue, 01 Sep 1987 00:00:00 GMT

Title: Toxic effects of Zn-oil mixture on Perna viridis (L.) Authors: Prabhudeva, K N; Menon, N R Abstract: Presence of LDO (light diesel oil) or HSD (high speed diesel) in the medium enhanced the toxicity of Zn on P. viridis, although Zn alone was less toxic. The 96 h LC₅₀ of Zn was 4.74 ppm (confidence limits: 5.36-4.2). A combination of 15% LDO and 2.27 ppm Zn (confidence limits: 2.54-2.02) brought about 50% mortality of test individuals in 96 h, whereas only 8.5% HSD and 1.78 ppm Zn (confidence limits: 1.91-1.66) caused the same. The combined action of Zn + LDO or Zn + HSD was more than additive (synergistic) in both the cases. The results clearly indicate that interaction between two or more pollutants can decidedly alter individual toxicities of the pollutants involved in the combination. Page(s): 199-200

Circulation in the northern Arabian Sea

Tue, 01 Sep 1987 00:00:00 GMT

Title: Circulation in the northern Arabian Sea Authors: Mathew, Basil; Muraleedharan, P M Abstract: Geostrophic flow field in the northern Arabian Sea is examined using 2 different data sets for early and late northeast monsoon. Earlier works and the present study suggest the possible occurrence of an anticyclonic eddy in the vicinity of the Murray Ridge throughout the year, though it is not clear whether some other eddies found in the northern Arabian Sea are transient or permanent. The persistence of anticyclonic eddy near Murray Ridge appears to be the effect of topographic interaction. Page(s): 196-198

Indentification of oil pollution sources in harbour waters

Tue, 01 Sep 1987 00:00:00 GMT

Title: Indentification of oil pollution sources in harbour waters Authors: Bhosle, N B; Fondekar, S P; Gupta, R Sen Abstract: Gas chromatography, infrared spectroscopy and UV-fluorescence analyses were made to establish the similarity of oil samples from the harbour waters and their suspected source. Results showed that 5 out of 7 samples tested were of the same origin while the other two were of different origin. Page(s): 192-195