RESEARCH INTERESTS:
I seek to understand the biogeochemical cycling of trace metals and macronutrients in aquatic environments. I am interested in the co-evolution of life and the early Earth, especially 1) how paleo-redox proxies are able to constrain the geochemistry of the environments that allowed early life to evolve and diversify in the Precambrian, and 2) how microbiological processes influence our interpretations of this geochemistry. I am also curious about temporal and spatial trends in biogeochemical cycling in modern systems, such as how climate change has influenced trace metal burial in Great Lakes sediments. As a result of these research interests, my work is interdisciplinary, spanning geochemistry, environmental sciences, limnology, and microbiology.
The Middle Island Sinkhole-- a low-oxygen freshwater environment with cyanobacterial mats at the sediment-water interface. This system is considered an analogue for ancient Proterozoic oceans.
Sampling from the Middle Island sinkhole has led to a research project that is highly collaborative, including researchers from the around the world who study water chemistry, microbial abundance, microbial metabolisms, and sediment geochemistry.
Two sediment cores from the Middle Island Sinkhole and Lake Huron. Differences in water column oxygen availability leads to visible differences in sediment geochemistry.
Purple cyanobacteria is intertwined with dark sediment in this frozen slab from a sediment core.
Shewanella oneidensis is a facultative anaerobe known for its ability to reduce metals such as iron, and for its pink hue at high densities!
My postdoctoral research incorporates incubation experiments wherein I monitor trace metal stoichiometry in association to microbial growth and diagenesis.
Presenting at the Geological Society of America conference in Baltimore, MD (2015). I am committed to presenting my research to the scientific community through oral presentations, poster presentations, and peer-reviewed publications.
RELEVANT PUBLICATIONS:
Rico, K. I., Schad, M., Picard, A., Kappler, A., Konhauser, K., Mahmoudi, M. (2023) Resolving the fate of trace metals during microbial remineralization of phytoplankton biomass in precursor banded iron formation sediments. Earth and Planetary Science Letters. doi: 10.1016/j.epsl.2023.118068
Gomes, M. L., Klatt, J. M., Dick, G. J., Grim, S. L., Rico, K. I., Medina, M., Ziebis, W., Kinsman-Costello, L., Sheldon, N. D., Fike, D. A. (2022) Sedimentary pyrite sulfur isotope compositions preserve signatures of the surface microbial mat environment in sediments underlying low-oxygen cyanobacterial mats. Geobiology. doi: 10.1111/gbi.12466
Rico, K. I., Sheldon, N. D., Kinsman-Costello, L. E. (2020). Associations between redox-sensitive trace metals and microbial communities in a Proterozoic ocean analogue. Geobiology. doi: 10.1111/gbi.12388
Rico, K. I., Sheldon, N. D., Gallagher, T. M., Chappaz, A. (2019). Redox chemistry and molybdenum burial in a Mesoproterozoic lake. Geophysical Research Letters. doi: 10.1029/2019GL083316
Rico, K. I., Sheldon, N. D. (2019). Nutrient and iron cycling in a modern analogue for the redoxcline of a Proterozoic ocean shelf. Chemical Geology. doi: 10.1016/j.chemgeo.2019.02.032
Montgomery, J.A., Klimas, C.A., Arcus, J., DeKnock, C., Rico, K., Rodriguez, Y., Vollrath, K., Webb, E., Williams, A. (2015). Soil quality assessment is a necessary first step for designing urban green infrastructure. Journal of Environmental Quality. doi:10.2134/jeq2015.04.0192
Rico, K. (2013). A characterization of marsh sediment at Prairie Wolf Slough Wetland. DePaul Discoveries. Available at: https://via.library.depaul.edu/depaul-disc/vol2/iss1/8