Research: Trace Metal Biogeochemistry; Metal-Binding Organic Ligands
Research in the Buck lab is focused on the biogeochemical cycling of trace metals in marine ecosystems, with particular emphasis on the role of metal-binding ligands in the cycling of bioactive trace elements like iron and copper. Iron (Fe) is an essential micronutrient for phytoplankton that limits primary productivity in large regions of the global open ocean. Copper (Cu), on the other hand, is a common anthropogenic contaminant to estuarine and coastal oceans that can act as a toxicant to microorganisms at elevated concentrations. The organic complexation of dissolved iron and copper by largely uncharacterized natural ligands in seawater has proven to be an integral component in the oceanic biogeochemistry of these metals, governing aspects of their solubility, supply and bioavailability in the marine environment.
Recent research projects in the Buck lab have examined the distributions, sources and sinks of natural iron- and copper-binding organic ligands in seawater, biological transformations of iron and copper species, and the influence of copper-binding ligands on bioavailability and toxicity of copper in contaminated coastal and estuarine environments. The Buck lab has current funding from the National Science Foundation to measure iron-binding ligand distributions on the U.S. GEOTRACES cruises in the North Atlantic and in the Eastern Pacific, and to evaluate the influence of iron-binding ligands on iron cycling processes in experimental studies. Dr. Buck is also currently a co-chair of the Scientific Committee on Oceanic Research (SCOR) Working Group 130: Organic Ligands- A Key Control on Trace Metal Biogeochemistry in the Ocean.