EGU21-3436
https://doi.org/10.5194/egusphere-egu21-3436
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Clearer than mud? Using environmental DNA to track historical shifts in lake communities.

John Pearman1, Laura Biessy1, Georgia Thomson-Laing1, Lizette Reyes2, Claire Shepherd2, Jamie Howarth3, Andrew Rees3, Xun Li2, Marcus Vandergoes2, Susie Wood1, and Team Lakes380
John Pearman et al.
  • 1Cawthron Institute, Nelson, New Zealand
  • 2GNS Science, Lower Hutt, New Zealand
  • 3Victoria University of Wellington, Wellington, New Zealand

A continuous record of environmental history is stored in lake sediments providing an avenue to explore current and historical lake communities. Traditionally paleolimnological methods have focussed on macroscopic indicators (e.g. pollen, chronomids, diatoms) to investigate environmental changes but the application of environmental DNA techniques has enabled the investigation of microbial communities and other soft bodied organisms through time. The ‘Our lakes’ health; past, present, future (Lakes380)’ project aims to combined traditional and molecular methods to explore shifts in biological communities over the last 1,000 years (pre-human arrival in New Zealand). Sediments cores have been collected from a wide diversity of lakes across New Zealand and 16S rRNA gene metabarcoding approaches of both DNA and RNA applied to reveal how microbial community changes across time and especially in response to the arrival of humans and associated changes to the landscape and lake environments. We further investigate the changes in inferred metabolic potential of the microbial communities as the taxonomic composition of the lake differs over time. Finally, we combine these novel molecular methods with hyperspectral scanning and pollen data to increase the knowledge of changes in lake communities and identifying the timing of changes in lake health. The combination of methodologies provides a greater understanding of the environmental history of lake systems and will help to inform management decisions relating to the restoration and protection of lake health.

How to cite: Pearman, J., Biessy, L., Thomson-Laing, G., Reyes, L., Shepherd, C., Howarth, J., Rees, A., Li, X., Vandergoes, M., Wood, S., and Lakes380, T.: Clearer than mud? Using environmental DNA to track historical shifts in lake communities., EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-3436, https://doi.org/10.5194/egusphere-egu21-3436, 2021.