Michael Shields
Assistant Research Scientist
Laboratory Manager
Organic Geochemistry, Biogeochemistry, Chemical Biomarkers
Research
I study the biogeochemistry of terrestrial, riverine, estuarine, and open ocean environments with an emphasis on carbon preservation and sequestration mechanisms.
My research focuses on the application of organic compounds as chemical biomarkers in tandem with carbon and nitrogen isotopes to track the sources and the diagenetic state of organic matter in sediment, soil, freshwater, estuarine, and open ocean ecosystems. In addition to modern processes, these chemical biomarkers record past environmental conditions and bio/geochemical processes.
Along with current research on natural organic matter, I am now incorporating both traditional and emerging organic contaminants such as PFAS into my research, which likely play a significant biogeochemical role in the Anthropocene.
Selected Publications
Recent First Author Publications (See CV or Google Scholar for complete list):
Shields, M.R., Bianchi, T.S., Osburn, C.L., Kinsey, J.D., Ziervogel, K., Schnetzer, A., Corradino, G., 2019. Linking chromophoric organic matter transformation with biomarker indices in a marine phytoplankton growth and degradation experiment. Mar. Chem. 214, 103665. https://doi.org/10.1016/j.marchem.2019.103665
Shields, M.R., Bianchi, T.S., Kolker, A.S., Kenney, W.F., Mohrig, D., Osborne, T.Z., Curtis, J.H., 2019. Factors controlling storage, sources, and diagenetic state of organic carbon in a prograding subaerial delta: Wax Lake Delta, Louisiana. J. Geophys. Res. Biogeosciences 2018JG004683. https://doi.org/10.1029/2018JG004683
Shields, M. R., T. S. Bianchi, D. Mohrig, J. A. Hutchings, W. F. Kenney, A. S. Kolker, and J. H. Curtis. 2017. Carbon storage in the Mississippi River delta enhanced by environmental engineering. Nat. Geosci. doi:10.1038/ngeo3044
Shields, M. R., T. S. Bianchi, Y. Gélinas, M. A. Allison, and R. R. Twilley. 2016. Enhanced Terrestrial Carbon Preservation Promoted by Reactive Iron in Deltaic Sediments. Geophysical Research Letters. 1–25. doi:10.1002/2015GL067388
Five Recent Publications (See CV or Google Scholar for complete list):
Morrison, E.S., M.R. Shields, T.S. Bianchi, Y. Liu, S. Newman, N. Tolic, and R.K. Chu. Multiple biomarkers highlight the importance of water column processes in treatment wetland organic matter cycling. Water Research. 115153.
Arellano, A. R., T.S. Bianchi, C. Osburn, E J. D’Sa, N.D. Ward, D. Oviedo-Vargas, I. Joshi, D. Ko, M.R. Shields, G. Kurian, and J. Green. (2019). Mechanisms of Organic Matter Export in Estuaries with Contrasting Carbon Sources. Journal of Geophysical Research: Biogeosciences, 124(10), 3168–3188. https://doi.org/10.1029/2018JG004868
Yao, P., X. Wang, T.S. Bianchi, Z. Yang, L. Fu, Z. Yu, X. Zhang, L. Chen, E. Morrison, M.R. Shields, Y. Liu, N. Bi, Y. Qi, S. Zhou, J. Liu, Y. Tian, X. Huang, J. Wang, D. Wu, H. Zhang, C. Zhu, C. Deng, and Z. Yu. Carbon cycling in the ocean’s deepest blue hole. J. Geophys. Res. – Biogeosci., 125(2): e2019JG00530.
- Featured in Nature Research Highlights, Ocean Sciences, February 28, 2020, Earth’s deepest ‘blue hole’ holds a cache of ancient carbon; https://www.nature.com/articles/d41586-020-00495-6.
- Featured in EOS Research Spotlight, Ocean Sciences, April 10, 2020, Carbon Cycling in the World’s Deepest Blue Hole; https://eos.org/research-spotlights/carbon-cycling-in-the-worlds-deepest-blue-hole.
Paerl, R.W., I.M. Claudio, M.R. Shields, T.S. Bianchi, and C.L. Osburn, 2020. Dityrosine formation via reactive oxygen consumption yields increasingly recalcitrant humic-like fluorescent organic matter in the ocean. Limnol. Oceanogr. Lett. https://doi.org/10.1002/lol2.10154
Vaughn, D.R., T.S. Bianchi., M.R. Shields, W.F. Kenney, and T.Z. Osborne, 2020. Increased Organic Carbon Burial in Northern Florida Mangrove‐Salt Marsh Transition Zones. Global Biogeochem. Cycles 34, 1–21. https://doi.org/10.1029/2019GB006334
Fortney, N, B. Beard, J. Hutchings, M. Shields, T. Bianchi, E. Boyd, C.M. Johnson, and Roden. Geochemical and stable Fe isotopic analysis of dissimilatory microbial iron reduction in Chocolate Pots hot spring, Yellowstone National Park (Accepted). Astrobiology
Education
PhD in Geological Sciences from the University of Florida (2016)
BS in Biochemistry from Texas A&M University (2011)
Additional Notes
Scientific Committee Member of the International Estuarine Biogeochemistry Symposium
