Oceanographic studies confirm that the decomposition and remineralization of organic matter at depth consume dissolved oxygen while releasing nutrients such as nitrate, resulting in inverse profiles of low oxygen and high nitrate.
The claim connects dissolved oxygen depletion at depth to nitrate accumulation driven by remineralization. Papers 3, 5, and 11 provide direct support for this fundamental biogeochemical coupling in ocean water columns. The remaining papers are irrelevant dental or material science studies.