The distribution and chemical form of iron (Fe) has a profound impact on marine life. In approximately 20% of the world's ocean, primary productivity is limited because phytoplankton cannot obtain enough Fe to satisfy their physiological needs. Therefore, small changes in seawater Fe concentrations can impact the growth of phytoplankton and affect the productivity of ecosystems, as well as the sequestration of carbon in the ocean. Despite the importance of Fe, many questions remain about the marine Fe cycle. For this reason, scientists from California Institute of Technology would determine the Fe isotopic fractionation in dissolved and particulate samples from San Pedro Basin and the Atlantic Ocean to provide new insights into the biogeochemical cycle of this metal. Specifically, the researchers plan to address the following questions: (1) What is the source of dissolved Fe in the world's oceans?; (2) Via what processes does marine particulate Fe become bioavailable?; and (3) Is dissolved del56Fe a tracer of biological cycling of Fe?
In regard to educational impact, funding from this research would support a graduate student and a postdoctoral researcher.