My research focused on microbial-biogeochemical interactions in how microbial activities can impact or respond to changing physiochemical conditions in lacustrine and marine environments and potential biosignatures (such as stable isotopes) preserved in lacustrine or marine sediments.
Microbial activities impact physiochemical conditions
To better understand how microbial activities can impact the physiochemical conditions in lacustrine and marine environments, I combine metagenomics and geochemical modeling to help improve interpretations of more traditional geochemical and petrographic measurements. By combing these tools, I have been able to improve our understanding of what controls d15N signatures in lake sediment cores (Chen et al., 2021). My ooid project is in turn clarifying why ooids of Kiritimati lakes have such high d13C values, and what drives the varying offset in d13C values between ooids and syndepositional carbonate mud, which is now in prep for submission to Geobiology.
Microbial activities respond to changing physiochemical parameters
My final dissertation project is investigating temporal variability in Kiritimati lake microbial communities and their functions, using amplicon sequencing methods (to be submitted to the ISME journal). I am observing substantial temporal changes in response to some extreme salinity changes, induced by high precipitation in an extreme El Niño event. I’m also comparing the microbial communities and functions in the sediment and adjacent water column to determine their different responses to physiochemical parameters changes in lacustrine ecosystems.
Plant eDNA preservation in US southwest transect lakes
I also have a collaboration project with Dr. James Bendle and his students from Birmingham University, which I extract plant DNA from the sediments collected in a series of lakes located in the US southwest transect. I’m currently looking at the plant communities reconstructed from eDNA and correlate them with 16S rRNA, biomarker and physiochemical parameter results to better understand the plant-microbe interactions in the US southwest transect.