Evaluating the use of lake sedimentary DNA in palaeolimnology: A comparison with long‐term microscopy‐based monitoring of the phytoplankton community

A pioneering study demonstrates that sedimentary DNA (sedDNA) can effectively reconstruct past phytoplankton communities, offering a promising tool for palaeolimnology. By comparing 18S rRNA gene amplicon sequencing from lake sediments of Esthwaite Water in the English Lake District with long-term microscopy-based monitoring data spanning ~105 years, researchers found broadly comparable trends in diversity and abundance among key phytoplankton groups such as chlorophytes, dinoflagellates, ochrophytes, and bacillariophytes. While sedDNA captured up to 20% of genera detected by microscopy, it also revealed previously undetected taxa, suggesting its potential for reconstructing historical phytoplankton dynamics. However, limitations such as reference database gaps and taphonomic processes underscore the need for further development to enhance reliability over longer timescales.

Thorpe, A. C., Mackay, E. B., Goodall, T., Bendle, J. A., Thackeray, S. J., Maberly, S. C., & Read, D. S. (2023). Evaluating the use of lake sedimentary DNA in palaeolimnology: A comparison with long‐term microscopy‐based monitoring of the phytoplankton community. Molecular Ecology Resources, 24(2). Portico. https://doi.org/10.1111/1755-0998.13903