English: Biogeochemical cycling of dissolved iron in the surface ocean<>br /> Schematic of key processes in the biogeochemical cycling of dissolved iron in the surface ocean. Abbreviations used in figure (see main text for details): LS, strong iron binding ligand; LW, weak iron binding ligand; FeLS, iron complexed by strong iron binding ligand; FeLw, iron complexed by weak iron binding ligand; Fe(II), all sum of all Fe(II) species; Fe′, the sum of all inorganic Fe(III) species; Fecol, colloidal iron species; Fepart, iron in the particulate phase; hv, photon flux; O2, dissolved oxygen; and H2O2, dissolved hydrogen peroxide.