Water Resources Research Act Program

Principal Investigators: John Peckenham

Abstract: The aim of this project is to investigate the relationships and mechanisms involved with complexes of dissolved organic carbon (DOC), iron (Fe) and phosphorus (P) during exposure to UV radiation. A series of batch solutions varied in concentration of DOC, Fe, and P are exposed to UV-A radiation (315 – 400 nm) for equivalent periods of time. The components of the experiment are analyzed for chemical and physical changes that affect how P is cycled photochemically. DOC absorption of UV radiation is expected to decrease with time during irradiation. This indicates that the DOC structure is altered which may lead to the possible breakdown of complexes and subsequent liberation of ionic Fe and P to the water column. These experiments are designed to examine this fundamental aspect of P cycling in surface waters containing DOC and Fe.