Grab what you can—an evaluation of spatial replication to decrease heterogeneity in sediment eDNA metabarcoding

• DOI: 10.7717/peerj.11619
• Publication Date: 2021-06-21T07:51:41Z
• Authors: Jon T. Hestetun; Anders Lanzén; Thomas G. Dahlgren
• Keywords: Environmental DNA; DNA Barcoding; Diversity index

Environmental DNA methods such as metabarcoding have been suggested possible alternatives or complements to the current practice of morphology-based diversity assessment for characterizing benthic communities in marine sediment. However, source volume used sediment eDNA studies is several magnitudes lower than that morphological identification. Here, we data from a North Sea sampling station investigate what extent affected by bias and spatial heterogeneity. Using three grab parallels, sampled five separate samples each grab. We then made extraction replicates sample. Each extract was amplified targeting both 18S SSU rRNA V1–V2 region total eukaryotic composition, cytochrome c oxidase subunit I (COI) gene metazoans only. In datasets, same sample were significantly more similar different Further, grabs less those 18S. Interestingly, this not true COI metabarcoding, where differences within between grabs. also investigated how much identified richness could be covered replicates, individual all single grab, well variability Shannon and, COI, macrofaunal biotic indices indicating environmental status. These results largely consistent with beta findings, show can represented using manageable number biological replicates. Based on these results, strongly recommend combination parts surface alternatively box cores similar. This will dilute effects dominating species increase coverage alpha diversity. COI-based consistency found compared 18S, but macrofauna-based direct measures.