Observations on the hydrographical features of the coastal waters of North Kanara during 1956-1966

Abstract

Observations on the hydrographical features of the coastal waters of North Kanara during 1965-1966 showed that the annual temperature values exhibited a bimodal distribution with the primary and secondary peaks in April/May and October/November periods and their falls during August/September and December/ January respectively. An abrupt fall in salinity was noticed during the southwest monsoon period, followed by a steady rise till May. The pH values varied around 8.2. The dissolved oxygen showed two peaks and two falls during a year, the peaks occurring in July/August and November/January and the falls during August-December and March/April-June respectively. Inorganic phosphorus recorded the maximum in September/October and the minimum in February/March with a single annual peak. The nitrite distribution was so random that no annual rhythm could be seen in its distribution. The silicate concentration was high during the period June to September and low values were registered in the pre-monsoon months.