Résumé
DNA sampled from the environment (eDNA) is a useful way to uncover
biodiversity patterns. By combining a conceptual model and empirical data,
we test whether eDNA transported in river networks can be used as an
integrative way to assess eukaryotic biodiversity for broad spatial scales
and across the land–water interface. Using an eDNA metabarcode approach,
we detect 296 families of eukaryotes, spanning 19 phyla across the
catchment of a river. We show for a subset of these families that eDNA
samples overcome spatial autocorrelation biases associated with the
classical community assessments by integrating biodiversity information
over space. In addition, we demonstrate that many terrestrial species are
detected; thus suggesting eDNA in river water also incorporates
biodiversity information across terrestrial and aquatic biomes.
Environmental DNA transported in river networks offers a novel and
spatially integrated way to assess the total biodiversity for whole
landscapes and will transform biodiversity data acquisition in ecology.