Microbial Nitrogen Transformations in the Oxygen Minimum Zone off Peru, 1985-02-01 to 1985-03-05 (NCEI Accession 9200026)

NITROP - 85 was the major field of experiment of an N.S.F. funded program entitled "Microbial Nitrogen Transformations in the Oxygen Minimum Zone off Peru". This project focused on obtaining a better understanding of the microbially mediated changes in nitrogen pathways and the controls on these pathways in and at the boundaries of the oxygen deficient water masses (O2 < 0.05 ml/l) found off Peru. The somewhat "random walk" nature of our cruise track and the existence of multi-cast stations reflects this emphasis. Considerable effort was expended on finding the right conditions to test various aspects of our hypotheses, and once a favorable site was located, many casts were necessary to obtain the large volume samples needed for some of our experiments. Since particle maxima appear to be well correlated with the nitrite maxima that are imbedded in the core of the oxygen deficient water masses, we also determined optical characteristics of the water at our sampling sites. Primary productivity and chlorophyll observations were also made during NITROP - 85.