Dr. G. Christopher Shank

One aspect of my research focuses on understanding the cycling of potentially toxic metals in coastal environments. Metals such as copper and mercury are introduced to the marine environment through numerous pathways including runoff, shipping and industry. Both of these metals can be extremely toxic to organisms at very low levels. My research investigates the processes that affect the cycling/toxicity of these metals in coastal waters including freshwater discharge and sediment/water exchange. I am also involved in a variety of marine photochemistry research projects. Solar radiation, especially high energy ultraviolet (UV) radiation, initiates numerous chemical reactions in surface waters. Photochemical reactions occur in sunlit waters due primarily to the ability of a specific fraction of the organic matter pool, known as chromophoric dissolved organic matter (CDOM), to absorb light energy (especially UV). I am interested how sunlight-induced reactions involving CDOM create bioavailable organic compounds as well as impact nutrient and metal cycles. My research also concerns the ability of CDOM to control light penetration through the water column. Because CDOM directly absorbs UV radiation, it serves as an important attenuator of UV to light-sensitive marine organisms. Corals reefs, for instance, are susceptible to damage from extended UV exposure. In the Florida Keys, CDOM in surface waters above the reefs provides a natural sunscreen to corals. My research specifically examines how variability in the CDOM pool (and suspended particles) affects the optical characteristics of the water column overlying these reefs.