Environmental DNA from archived leaves reveals widespread temporal turnover and biotic homogenization in forest arthropod communities
- University of Trier, Germany
- German Federal Environment Agency, Germany
- Max Planck Institute for Evolutionary Biology, Germany
- Ludwig Maximilians University, Germany
Abstract
A major limitation of current reports on insect declines is the lack of standardized, long-term, and taxonomically broad time series. Here, we demonstrate the utility of environmental DNA from archived leaf material to characterize plant-associated arthropod communities. We base our work on several multi-decadal leaf time series from tree canopies in four land use types, which were sampled as part of a long-term environmental monitoring program across Germany. Using these highly standardized and well-preserved samples, we analyze temporal changes in communities of several thousand arthropod species belonging to 23 orders using metabarcoding and quantitative PCR. Our data do not support widespread declines of α-diversity or genetic variation within sites. Instead, we find a gradual community turnover, which results in temporal and spatial biotic homogenization, across all land use types and all arthropod orders. Our results suggest that insect decline is more complex than mere α-diversity loss, but can be driven by β-diversity decay across space and time.
Data availability
All raw reads are available in the Dryad Digital Repository (https://doi.org/10.5061/dryad.x0k6djhmp).The OTU table with metadata and qPCR resullts has been uploaded as Supplementary Material
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eDNA from archived leaves reveals no losses of α-diversity, but widespread community turnover and biotic homogenization as drivers of forest insect declineDryad Digital Repository, doi:10.5061/dryad.x0k6djhmp.
Article and author information
Author details
Henrik Krehenwinkel
Funding
No external funding was received for this work.
Copyright
© 2022, Krehenwinkel et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Environmental DNA from archived leaves reveals widespread temporal turnover and biotic homogenization in forest arthropod communities
eLife 11:e78521.
https://doi.org/10.7554/eLife.78521
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