|MadSci Network: Environment|
A suggestion would be to get some sea salt from an aquarium store that is used for salt water aquariums, analyze the salt water for iron content. You may want to see if a local university can do this for you using Atomic Absorption Spectrophotometery, or there are wet chemistry methods available.
Use this as your control, adjust the Iron content of this synthetic sea water for your samples.
You may want to look at the work of Jim Bishop and Todd Woods. ďOceanic Carbon: A Dent in the iron Hypothesis.
Bishop and Todd point out that all iron enrichment experiments have created plankton blooms. This does not necessarily lead to long term (decades/centuries) of enhanced carbon sequestration by the ocean.
The reason is that in many of the experiments, the carbon taken up by phytoplankton does not get exported to the deep sea on sinking particles. So far, the opposite results are found... bloom but less sequestration.
Iron is not the only factor that determines plynktonic growth in HNLC regions, light, mixing, and hungry zooplankton are fundamentally as important as Iron. You canít control for these in the oceansí, but you may be able to in the laboratory.
The point is the Hypothesis isnít wrong, but much more subtle than usually stated.
Hope this helps.
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