A STUDY OF THE SEASONAL CHANGES IN THE DISSOLVED OXYGEN OF THE SURFACE WATERS OF THE SEA ON THE MALABAR COAST

Abstract

There is wide recognition at the present day of the importance of hydrographical investigations, particularly in association with biological studies of the marine environment. A knowledge of the physics and chemistry of sea-water is essential for a scientific approach to the fundamental problem of organic production in the sea and, in certain instances, greatly helps in the solution of specific problems connected with fisheries. Investigations on the distribution and seasonal variations of temperature, salinity, dissolved oxygen, pH and of various inorganic compounds of phosphorus, nitrogen and silicon, —usually referred to as " nutrient salts,"—have been carried out in many countries abroad largely in temperate latitudes (Harvey, 1945). Work in tropical waters has not been on the same scale and most of it is of recent date.