Journal of the Marine Biological Association of India

Studies on foam.

Volume 17 Issue 2

AL.Paul Pandian and V. K. Venugopalan

Abstract

Under light wind conditions, long lines of surface slicks and patches of foam appear quite commonly in the Vellar Estuary. The foam is of a very stable type, and persists normally for from several minutes to a few hours and collect in large masses along the shores in the lower part of the estuary.

Microscopic examination of freshly collected foam revealed the presence of a considerable amount of phytoplankton (chiefly species belonging to the; genera Coscinodiscus and Trichodesmium) and detrital material in addition to fine silt particles.

The foam samples were chemically analysed for the anions like Nitrate, Phosphate and Silicate and cations such as Iron, Copper and Manganese. The foam seems to be very rich in these constituents, the concentration being a hundred fold more than those of sea water (except reactive silicate). The range of variation in the concentration of the above constituents is as follows:

Range µg/gm            dried foam

Nitrate                                     1345.0             to          3430.0

Phosphate                                  550.0             to             650.0

Silicate (cold reactive)              146.0             to             233.0

Iron                                       18206.0             to         37967.0

Copper                                                5272.0             to           9887.0

Manganese                                420.0             to             678.0

 

Further, the chemical composition as well as water content collected during different periods vary considerably.

Date : 30-08-1975