Oxygen-nutrient relationships in the Pacific Ocean1

In the northeastern Pacific Ocean the oxygen-phosphate and oxygen-nitrate relationships vary systematically with latitude. The variation above the oxygen minimum zone is much more pronounced than below it. The slopes of these relationships in general increase with increasing latitude. In the entire water column these slopes vary with depth. A seasonal effect on the slopes of the oxygen-phosphate and oxygen-nitrate relationships, similar to that with decreasing latitude, is observed; the winter slopes are higher than the summer slopes. Potential temperature versus preformed phosphate diagrams were constructed for different stations in the Pacific and Indian Oceans to study their water masses. Postma ( 1964) plotted dissolved oxygen concentrations, 02, versus phosphate con-centrations, P04, from stations at different latitudes (55”N to 62’S) in the Pacific Ocean, and found a variable A o2: APO, ratio with depth. Pytkowicz (1964) an