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An investigation of the iron (Fe) perturbations needed to stimulate diatom production requires an assessment of the lowest Fe concentration whereby uptake still allows maximum cellular growth rates and of what Fe flux to surface waters is then required to sustain high diatom productivity once the concentration threshold is exceeded. Research in this area has concluded that climate forcing has definitely had an impact on productivity in the eastern equatorial Pacific. Furthermore, equatorial sediment records give an insight into these impacts. However, some element of this cycling may have been fuelled by localized tectonic processes in the Papua New Guinea island-arc area.

Marine colloids are abundant in the oceans representing 30-50% of the dissolved organic carbon. There is a lack of consensus about the processes that regulate colloid cycling. Chin and colleagues have invoked a polymer gel theory to explain the behaviour of marine colloids. They show the significance of nonspecific surface interactions in colloid cycling and have discovered that discrete natural polymers coalesce spontaneously, forming large, sinking conglomerates. Particulate gels were found to re-form from soluble and colloidal precursors, after the removal of previous gels via filtration.

Four hundred and eighty kilograms of iron was introduced in the Pacific Ocean, 500 kilometers south of Galapagos Islands, to investigate the influence of iron on biomass and phytoplankton production. The region near Galapagos islands consists of abundant supply of plant nutrients. The investigation reveals that the concentration of iron in these regions does not influence biomass and phytoplankton production.