Department of Chemistry & Biochemistry
Arizona State University
My research in biogeochemistry focuses on how geochemical, microbial, and anthropogenic processes affect the dynamic linked elemental cycles in modern, and paleo-environments. A variety of field- and laboratory-based techniques are applied to investigate the processes and feedbacks that promote and/or limit the transfer of elements (i.e., C, N, and P) and energy between different geological pools; including living and non-living organic matter as well as various inorganic reservoirs.
These studies require investigations of mechanisms that operate on time scales from days to millenia. The main goal is to gain a better understanding of the interactions between the physical, chemical and biological processes that control the distributions of these climatically important elements and how they change through time. Current research projects include: the characterization of dissolved organic matter in aquatic and marine systems, and investigation of the bioavailability and reactivity of dissolved organic compounds in natural waters. State-of-the-art analytical approaches are used to quantify and characterize organic matter in a broad range of natural systems (i.e., marine, aquatic and terrestrial), including the development of novel mass-spectrometric techniques for identifying and quantifying natural organic compounds. Ultimately this research seeks to develop more a mechanistic understanding of biogeochemical processes and how they relate to global scale patterns.
Some of my earlier research involved investigating the complex controls on organic carbon preservation in aerobic and anaerobic marine systems, development of a probe-inlet for MIMS analysis of atmospheric gases to measure microbial oxidation rates (e.g., oxygen consumption and denitrification) in sediments, and the chemical characterization of rainwater DOM.