DOI: 10.5061/dryad.nvx0k6f32
title: Data from: Comparing the fate of eDNA by particle sizes and molecule lengths in recirculating streams

description: The detection of environmental DNA (eDNA) has revolutionized aquatic
 species monitoring, yet interpreting eDNA data remains challenging due to
 gaps in our understanding of eDNA ecology (i.e., origin, state, transport,
 and fate) and variability in how eDNA methods are applied across the
 literature. A crucial aspect of the complexity of eDNA ecology is that
 eDNA is a heterogeneous mix of components that vary in size and other
 properties, thereby influencing interactions with the environment in
 diverse ways. In this study, we explore the interplay between three eDNA
 particle sizes (the physical dimension of eDNA‐containing particles) and
 two molecule lengths (DNA size in base pairs) in flowing water systems.
 Specifically, we elucidated the mechanisms governing the removal of
 different eDNA components using a set of 24 recirculating mesocosms where
 we varied light and substrate conditions. Consistent with previous
 observations, our findings revealed substantial differences in the
 mechanisms of eDNA removal between small and large eDNA particles. In
 mesocosms with biofilm‐colonized substrate, we found higher removal rates
 for smaller particles, but larger eDNA particles were removed more quickly
 in presence of any substrate. Importantly, we also found that biofilm
 removes longer eDNA molecules faster, shedding light on a probable
 mechanism underlying the longstanding association between eDNA removal and
 the presence of biofilm. Despite the association between biofilm
 colonization and faster removal of longer molecules, the two eDNA molecule
 sizes we analyzed (86 and 387 base pairs) exhibited somewhat consistent
 behavior. In combination, our observations highlight that particle size is
 an important predictor of eDNA fate, and that eDNA fate shows few
 differences across varying molecule lengths. Furthermore, our work
 suggests that conclusions regarding eDNA ecology from studies utilizing
 short DNA markers are applicable to metabarcoding applications, which
 typically use longer marker lengths.
description: # Comparing the fate of eDNA by particle sizes and molecule lengths in
 recirculating streams
 [https://doi.org/10.5061/dryad.nvx0k6f32](https://doi.org/10.5061/dryad.nvx0k6f32) ## Description of the data and file structure This directory contains supplementary figures to the manuscript, as well as the raw data used in the manuscript. If further information is required to replicate the findings of #this manuscript, please do not hesitate to contact me (Pedro Brandão, corresponding author of the manuscript) **File descriptions:** * Raw_data_supplement_partsizevsmollength.csv  This is the raw dataset, containing the ddPCR concentrations and other relevant information to derive the eDNA concentrations in each stream by treatment, filter size, and marker. Missing data given as NA. Columns are described in the metadata file in further detail * Metadata.csv This describes the columns in the raw data described above. * Nested_supplement_R2.PDF This is a file containing the supplemental figures for the manuscript, which are referenced in the main text