Abstract
The distribution of iron in two size fractions (<0·025 and <0·45μm) was studied in various coastal waters from northern Japan and in oceanic water, and it was found that estuarine waters and surface waters in Funka Bay (Hokkaido) had the highest colloidal iron concentrations (0·025–0·45-μm fraction, 7–19nM), with a large portion (85–93%) in the <0·45μm fraction. The high colloidal iron concentrations in estuarine and bay surface waters were probably due to the rapid formation or contribution of colloidal iron through riverine and atmospheric inputs, respectively. Dissolved organic substances, such as humic substances and other organic Fe(III) chelators, possibly contributed to the formation and stabilization of the colloidal iron fraction in seawater. In addition, ultraviolet (UV)-irradiation treatment of coastal and estuarine waters reduced the iron concentrations in all size fractions (<0·025μm, 0·025–0·45μm, <0·45μm) and the Fe(III) hydroxide solubilities, resulting from the decomposition of natural organic iron chelators. These results suggest that natural organic Fe(III) chelators control the colloidal and dissolved iron concentrations in seawater.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
