Oxygen-deficient zones

For reasons given earlier, dissolved 02 concentrations in much of the mes-opelagic Arabian Sea (depth range -150-1000m) are below 0.1 mil-1 ( 4pM, Fig. 6.14a), making it one of the largest and the most intense 02-deficient zones (ODZs) in the world. The most 02-deficient waters are found north of -12° N latitude (Fig. 6.14a), the approximate position of the zero wind stress curl (Warren, 1994), where suboxic (02 1 pM) conditions profoundly influence 

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Up until a few years ago the general understanding was that in the world s oxygen deficient zones, heterotrophic denitrification was the sole mechanism... 

Figure 6.15 Profiles of del N of N2 and NO3 through the oxygen deficient water of the eastern tropical North Pacific (left) and Arahian Sea (right). The shaded area represents the oxygen deficient zone. Redrawn from Brandes eta/., 1998.

Devol, A. H., and Hartnett, H. E. (2001). Role of the oxygen-deficient zone in transfer of organic carbon to the deep ocean. Limnol. Oceanogr. 46, 1864-1690. 

Kilpatrick (1991) and oxygen deficient zones of the Cariaco Trench... 

Liu, X. D., Tiquia, S. M., Holguin, G., Wu, L. Y., Nold, S. C., Devol, A. H., et al. (2003). Molecular diversity of denitrifying genes in continental margin sediments within the oxygen-deficient zone off the Pacific coast of Mexico. Appl. Environ. Microbiol. 69, 3549—3560. 

Keil R. G. and Cowie G. L. (1999) Organic matter preservation through the oxygen-deficient zone of the NE Arabian Sea as discerned by organic carbon mineral surface area ratios. Mar. Geol. 161, 13-22. 

Devol A. H. (1978) Bacterial oxygen uptake kinetics as related to biological processes in oxygen deficient zones of the oceans. Deep-Sea Res. 25, 137-146. 

Carbon monoxide and carbon dioxide appearing in the combustion products are generated from the intermediate, formaldehyde in the oxygen-deficient zone ... 

FIGURE38.il Micro-corrosion cells, (a) Grain boundaries are anodic with respect to the grain interior, (b) Crevice corrosion due to oxygen-deficient zone in metal s environment. 

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