Unlocking the Secrets of Past Coastal Catastrophes : Using sedimentary ancient DNA (sedDNA) to investigate Storm and Tsunami Deposits

Sedimentary ancient DNA (sedDNA) is emerging as a powerful tool for studying storm and tsunami deposits, offering novel insights into past events and their ecological impacts. By analyzing sedDNA from microbial communities preserved in known tsunami and storm-deposited sediments, researchers can distinguish between these deposits and non-overwash sediments. This method has been successfully applied to sites impacted by the Palu tsunami in 2018, where we distinguish between tsunami and non-tsunami deposits in different geological settings and to the deposits of the 2004 Indian Ocean Tsunami and subsequent storm events, demonstrating significant differences in microbial communities (Yap et al., 2021). Despite challenges related to sample preservation and data interpretation, the integration of sedDNA with traditional methods holds promise for enhancing our understanding of sedimentary processes and ecological shifts associated with catastrophic natural events. Combining sedDNA with traditional sediment analysis can provide a more comprehensive understanding of past environmental events. Furthermore, sedDNA has shown potential longevity in tsunami deposits (Yap et al., 2023), preserving microbial community signatures for up to several millennia.

Yap, W., Switzer, A. D., Gouramanis, C., Marzinelli, E., Wijaya, W., Yan, Y. T., ... & Lauro, F. M. (2021). Environmental DNA signatures distinguish between tsunami and storm deposition in overwash sand. Communications Earth & Environment, 2(1), 129.

Yap, W., Switzer, A. D., Gouramanis, C., Horton, B. P., Marzinelli, E. M., Wijaya, W., ... & Lauro, F. M. (2023). Investigating geological records of tsunamis in Western Thailand with environmental DNA. Marine Geology, 457, 106989.