Soluble and Colloidal Iron in the Oligotrophic North Atlantic and North Pacific

• DOI: 10.1126/science.1059251
• Publication Date: 2002-07-27T09:39:52Z
• Authors: Jingfeng Wu; Edward Boyle; William Sunda; Liang-Saw Wen
• Keywords: Settling; Ultrafiltration (renal)

In the oligotrophic North Atlantic and Pacific, ultrafiltration studies show that concentrations of soluble iron iron-binding organic ligands are much lower than previously presumed "dissolved" concentrations, which were operationally defined as passing through a 0.4-micrometer pore filter. Our indicate substantial portions (and probably also ligands) present in colloidal size range. The depleted at surface enriched depth, similar to distributions major nutrients. By contrast, shows maximum minimum upper nutricline. results suggest may be less bioavailable phytoplankton thought removal colloid aggregation settling should considered models oceanic cycle.