1980 - National Institute of Oceanography

particular substance has been detected in Caulerpa racemosa (hypotensive), Padina
tetrastomatica (spasmogenic), Corallina (spasmogenic) and Chondria armata (spasmogenic).
It is to be confirmed whether the activity reported is due to the presence
of histamine. The extracts of Sargassum tenerrimum, Galaxaura elongata, Galaxaura
rugosa, Ulva reticulata, Chondrococcus sp. and Codium elongatum were found to be
devoid of histamine.
4. Halogens in algae
Iodine and bromine contents were measured in 16 species of red, brown and
green algae. In all the species examined the concentration of iodine was found to be
lower than that of the bromine. Phaeophyta and Rhodophyta were found to be
relatively richer in both these elements. The iodine concentration varied from 0.003
to 0.119% and bromine from 0.008 to 0.128%.
3.2.3 Protection of marine environment and monitoring of pollutants along the Indian coast
The studies under this project were carried out partly from headquarters and
partly from Regional Centres, Cochin and Bombay.
1. Monitoring of petroleum hydrocarbons in the marine environment
Two cruises were carried out along the oil tanker routes across the southern
Bay of Bengal from south of Sri Lanka to the head of the Malacca Strait. The area
traversed was between 5°30' to 6°30'N latitude and 78°00' to 98°30'E longitude.
A part of the Andaman Sea was also surveyed. The components observed were: oil
slicks, floating pollutants, particulate petroleum residues (tar balls) and dissolved/
dispersed hydrocarbons.
Depthwise mean concentration in μg/kg of dissolved/dispersed petroleum hydrocarbons
along the oil tanker route in the Arabian Sea and Bay of.Bengal are as
follows:
Arabian Sea (μg/kg) Bay of Bengal (μg/kg)
Depth Mean Range Mean Range
0 m 35.3 0-395 29.1 4-229
10 m 30.6 3-217 25.1 2-147
20 m 29.4 2-112 17.6 1-75
Mean 32.5 Mean 24.1
Computation on the total volume of petroleum hydrocarbons in the upper
20 m of the Arabian Sea and the southern Bay of Bengal gave figures of 4 x 10 6
and 0.4 x 10 6
tonnes respectively.
2. Laboratory studies on biodegradation
Investigations have been initiated to isolate tar-degrading organisms by sequential
degradation method. Laboratory studies gave encouraging results but field
trials on the tar deposition on beaches presented some difficulties due to wind and
surf activities. Modifications are being tried to overcome these problems.
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