Rob Middag

I study the role of metals in marine systems. Metals such as iron are essential nutrients for algae, which form the basis of the marine food web. Iron is extremely scarce in the ocean: typically less than the equivalent of one paperclip dissolved in fifteen swimming pools of seawater. Measuring such tiny concentrations is a major challenge.

Algae respond not to single nutrients, but to a delicate balance of many ingredients, including nitrogen, phosphorus, and trace metals. More iron does not automatically mean more growth if something else is missing. Instead, the relative mix of nutrients and metals helps determine which algae flourish and which fade away. Through this balance, metals quietly shape marine communities and influence how ocean ecosystems respond to a changing world.