Indian Ocean water balance

Large-scale iron fertilization will have side-effects. If iron fertilization resulted in a complete drawdown of the nutrients available in the Southern Ocean, for example, the average O2 content of deep waters will drop by 4-12% (Sarmiento and Orr, 1991), with areas of anoxia cropping up in the Antarctic (Peng and Broecker, 1991b) and Indian Oceans (Sarmiento and Orr, 1991). Even small-scale patches of anoxia would have a profound negative impact on the survival and distribution of metazoan fauna in the ocean and alter the balance of microbial transformations of nitrogen between reduced and oxidized phases (Fuhrman and Capone, 1991). 

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