Study on the distribution and correlation of inorganic phosphorus and dissolved oxygen and nitrites and inorganic phosphorus at Karwar during 1965-1972 is made. The oxygen and phosphorus are inversely related at depths. The Bay waters showed high oxygen content at surface and low content at depths and sea beds. But the waters outside the bay showed high dissolved oxygen content in the depths than at the surface. Here the subsurface waters showed supersaturations as against practically none in the bay waters. The correlation coefficient (r) obtained for dissolved oxygen and inorganic phosphorus during this investigation was 0.53 and found to be significant at 5 and 1 per cent level.

As regards the distribution of nitrites and inorganic phosphorus, there is a close parallelism between nitrites and inorganic phosphorus and which is characterised by the presence of low concentration at surface and the increasing concentration at depths- The correlation coefficient (r) was found to be not significant at 5 and 1 per cent levels, the (r) value being 0.09. Similarly, the relationship between dissolved oxygen and nitrite when studied, the correlation coefficient of 0.26 proved to be significant at 5 and 1 per cent levels.

These nutrients bear a definite linearity at all levels. As the inorganic phosphorus and dissolved oxygen show inverse relation, and as the inorganic phosphorus and nitrite bear linearity, it is obvious that the relation between dissolved oxygen must also be inverse at depths. As the plant life much depends on the concentrations of these nutrients, it is of much value to study the distribution, interrelations and fluctuations of nutrients in the sea.