Data from: Erosion regime controls sediment environmental DNA-based community reconstruction

Analysis of environmental DNA detected in lake sediments shows promise to
become a great paleoecological technique that can provide detailed
information about organism communities living in past environments.
However, when interpreting sedimentary environmental DNA records, it is of
crucial importance to separate ecosystem responses to large-scale
environmental change from ‘noise’ caused by changes in sediment provenance
or potential post-depositional DNA mobility. In this study, we show that
plant and mammalian communities reconstructed from sediments are strongly
affected by sediment provenance, but unaffected by vertical mobility of
DNA after sediment deposition. We observe that DNA from aquatic plants was
abundant in background sediment, while embedded detrital event layers
(sediment deposited under erosion events) primarily contained terrestrial
plants; hence, vertical mobility of aquatic plant DNA across sediment
layers was negligible within our studied lakes. About 33% of the
identified terrestrial plant genera were only found in detrital sediment
suggesting that sediment origin had a strong impact on the reconstructed
plant community. Similarly, DNA of some mammalian taxa (Capra hircus,
Ursus arctos, Lepus, Felis) were only or preferentially found in detrital
event layers. Temporal changes across the Holocene were the main drivers
of change for reconstructed plant communities, but sediment type was the
second most important factor of variance. Our results highlight that
erosion and sediment provenance need to be considered when reconstructing
past mammalian and plant communities using environmental DNA from lake
sediments.