• Educational Background
• Research Interests
• Current Projects
• Teaching
• Publications

Educational Background

• Ph.D., 1995, Chemical Oceanography
  Florida State University
• M.S., 1991, Chemical Oceanography
  Florida State University
• B.S., 1988, Chemistry
  Wake Forest University

Research Interests

• My primary interests are in the biogeochemistry of trace metals. Within this there are several areas of particular interest: Method development. Since many metals exist at picomolar to nanomolar levels (10-12 to 10-9 molar) in natural systems, their analysis is extremely difficult considering many other constituents in seawater may be at much higher levels (i.e., micromolar organic carbon or molar sodium and chloride). This area of research remains one of the great challenges to analytical chemists particularly those that are interested in studying only a small fraction of the total metal concentration in order to understand reaction mechanisms and bioavailability.
• Trace metal speciation. Many methods are being developed to study not only total metal concentrations but also metal speciation (in what form does the metal exist, i.e. reduced, oxidized, organically complexed, colloidal). The speciation of an element determines its bioavailability and possible influences on biological cycles.
• River/Ocean Interactions. Large rivers account for a disproportionately large amount of organic carbon burial in the world's oceans. Of particular interest in my research is the role of nutrients and trace metals on controlling the optical properties, productivity and eventual carbon burial in these systems.

Current Projects

• Controls on the optical properties of coastal waters in the northern Gulf of Mexico
• Long-term Estuary Assessment Group (LEAG): Science in Service of Policy in the Mississippi River / Gulf of Mexico Estuary
• Mississippi River Interdisciplinary Research
• Electroanalytical Technique
• Hydrocarbon and Metal Contamination
• Wind Events
• Organic Complexation
• Colloids

Teaching

• Introduction to Marine Science
• Aquatic Chemistry
• Biogeochemical Field Methods
• Our Changing Coastal Ocean

Publications

• Measures, C.I., G.A. Cutter, W.M. Landing, and R.T. Powell. 2006. Hydrographic observations during the 2002 IOC Contaminant Baseline Survey in the western Pacific Ocean. Geochem. Geophys. Geosyst., 7, Q03M06, doi: 10.1029/2004GC000855.
• Dagg, M. J., T. S. Bianchi, G. A. Breed, W. J. Cai, S. Duan, H. Liu, B. A. McKee, R. T. Powell, and C. M. Stewart. 2005. Biogeochemical characteristics of the lower Mississippi River, USA, during June 2003. Estuaries. 28: 664-674.
• Yuan, J., R. L. Miller, R. T. Powell, and M. J. Dagg. 2004. Storm-induced injection of the Mississippi River plume into the open Gulf of Mexico. Geophysical Research Letters 31: L09312, doi:10.1029/2003GL019335.
• Powell, R. T. and A. Wilson-Finelli. 2003. Photochemical degradation of organic Fe complexing ligands. Aquat. Sci. 65(4): 367–374.
• Powell, R. T. and A. Wilson-Finelli. 2003. Importance of organic Fe complexing ligands in a buoyant river plume. Estuar. Coast. Shelf Sci. 58(4): 757–764.
• Powell, R. T. and M. R. Alexander. 2003. Trace metal contamination in sediments of Barataria Bay, Louisiana. Bull. Environ. Contam. and Toxicol. 71(2): 308–314.