Environmental DNA OOE Cruise 2021051 – Investigating Ocean diversity and climate impact through quantitative assessment of selected marine taxonomic groups

Molecular biology methods, such as environmental DNA (eDNA)analysis, are the new frontier in biodiversity assessments. Understanding the status of ocean biodiversity and impact of climate change on the composition, structure and function of marine ecosystems is crucial to sustainable management of the ocean and coastal areas. Within the eDNA activity on board of the One Ocean Expedition (OOE), a total of 240 water samples will be collected and 60 of them will be analyzed onsite using a portable PCR device. Weekly analysis of eDNA will provide hundreds of data points around the globe to assess the presence and abundance of 11 key marine indicators from marine unicellular prokaryotes to fish that may be impacted in one way or another by ocean and climate change. The geographical mapping of these species across all oceanic regions of the globe will provide new knowledge, status, and insights into how species may redistribute in a changing ocean resulting from global warning and other anthropogenic stressors. The rest of the collected samples will be analyzed with higher resolution using high-throughput sequencing (HTS) techniques to infer marine species inventory and biodiversity distribution at a scale seldom possible in scientific cruises, providing a snapshot of marine biodiversity globally. The results provided in the datasets are automatically tagged with a quality flag according to SeaDataNet standards: https://www.seadatanet.org/content/download/596/file/SeaDataNet_QC_procedures_V2_%28May_2010%29.pdf QC = 0 - no quality check QC = 1 - good QC = 2 - probably_good QC = 3 - probably_bad Quality = 2 was assigned if the assay was not valid but there was valid replication in one (out of possible 3) PCR results. Quality = 3 was assigned if the melting point lies outside of the required range. In this case the abundance is set to zero.