Iron uptake and physiological response of phytoplankton during a mesoscale Southern Ocean iron enrichment

摘要

Iron supply is thought to regulate primary pro- duction in high nitrate, low chlorophyll (HNLC) regions of the sea in both the past and the present. A critical aspect of this relationship is acquisition of iron (Fe) by phytoplankton, which occurs through a complex series of extracellular reac- tions that are influenced by Fe chemistry and speciation. Dur- ing the first in situ mesoscale Fe-enrichment experiment in the Southern Ocean (Southern Ocean iron release experiment [SOIREE]), we monitored the uptake of Fe by three size clas- ses of plankton and their ensuing physiological response to the Fe enrichment.