270209 PR Environmental chemistry lab course including scientific fieldwork (2011S)

Much attention has been focused on iron limitation as a mechanism to explain the relatively high oceanic concentrations of phosphate. The promise of climate geoengineering by artificial iron fertilization of the ocean is that shifting nutrients from the biologically unutilized (or preformed) phosphate pool to the biologically utilized (or remineralized) pool allows the ocean to hold more carbon. This carbon will be taken out of the atmosphere. Several successful open ocean iron enrichment studies have been undertaken. However, detrimental side effects of artificial iron fertilization cannot be ruled out.
In the framework of the lab course, we will investigate the importance of natural terrestrial iron sources. Peat bogs have the ability to produce strong iron binding chelate ligands which enhance the weathering rates of iron-silicate minerals and greatly increase the solubility of the essential trace metal iron in river water and in seawater. During the lab course, iron-binding dissolved lignin and other chelating ligands will be isolated from river water.