Annual time-series analysis of aqueous eDNA reveals ecologically relevant dynamics of lake ecosystem biodiversity

Iliana Bista (1) , Gary R. Carvalho (1) , Kerry Walsh (2) , Mathew Seymour (1) , Mehrdad Hajibabaei (3) , Delphine Lallias (4, 5) , Martin Christmas , Simon Creer (1)

1 Molecular Ecology and Fisheries Genetics Laboratory, School of Biological Sciences
2 Horizon House
3 Department of Integrative Biology & Biodiversity Institute of Ontario
4 GABI - Génétique Animale et Biologie Intégrative
5 Université Paris-Saclay

The use of environmental DNA (eDNA) in biodiversity assessments offers a step-change in sensitivity, throughput and simultaneous measures of ecosystem diversity and function. There remains, however, a need to examine eDNA persistence in the wild through simultaneous temporal measures of eDNA and biota. Here, we use metabarcoding of two markers of different lengths, derived from an annual time series of aqueous lake eDNA to examine temporal shifts in ecosystem biodiversity and in an ecologically important group of macro-invertebrates (Diptera: Chironomidae). The analyses allow different levels of detection and validation of taxon richness and community composition (beta-diversity) through time, with shorter eDNA fragments dominating the eDNA community. Comparisons between eDNA, community DNA, taxonomy and UK species abundance data further show significant relationships between diversity estimates derived across the disparate methodologies. Our results reveal the temporal dynamics of eDNA and validate the utility of eDNA metabarcoding for tracking seasonal diversity at the ecosystem scale.

Mots clés: chironompupal exuviae; environmental dna; abundance; capture; identification; amplification; conservation; arthropods; primers; tool

Domaines: Sciences du Vivant [q-bio]

Iliana Bista, Gary R. Carvalho, Kerry Walsh, Mathew Seymour, Mehrdad Hajibabaei, et al.. Annual time-series analysis of aqueous eDNA reveals ecologically relevant dynamics of lake ecosystem biodiversity. Nature Communications, 2017, 8, pp.1-11. ⟨10.1038/ncomms14087⟩. ⟨hal-01607796⟩