There is increasing recognition that iron distribution and availability is significant in terms of global oceanic production. Low availability of iron and other nutritive trace metals may also constrain productivity in the North American Great Lakes. Despite its importance, the biogeochemistry of iron in the water column of lacustrine systems remains poorly characterized. In addressing the current state of iron biogeochemistry, a workshop organized a decade ago at the Bermuda Biological Station for Research brought together a cross-disciplinary team of chemists and biologists who sought to synthesize current knowledge and identify research priorities in this field. Key among goals identified during the workshop, and one that remains today for the most part unfulfilled, was to 'develop techniques to quantify those fractions of Fe that are accessible to phytoplankton.' Here we review recent progress toward meeting this objective, drawing on specific examples from Lake Superior where these approaches have been applied.
Bibliographical noteFunding Information:
This material is based upon work supported by the National Science Foundation under Grant numbers OCE-9911592 and DBI-0070334 (R.M.L.M. and G.S.B.), MCB-9634049 (G.S.B.), OCE-000298 (S.W.W.) and OCE-9902658 (R.M.L.M., R.M.S., E.T.B. and R.W.S.). Additional support for preliminary data behind many of the ideas presented in this contribution comes from Ohio Sea Grant under contract number R/ER-49-PD (R.M.L.M.), the Natural Sciences and Engineering Research Council of Canada (M.R.T.), Environment Canada and the University of Tennessee Office of Research (S.W.W.). R.M.L.M. would like also to thank Sarah Green (Michigan Technological University) for the opportunity to collect field samples as part of the NSF-CoOP KITES project. The authors thank the captains and crew of the R/V Laurentian and the R/V Blue Heron for assistance with field collections.
- Lake Superior
- Trace metal speciation