title: High-throughput metabarcoding of eukaryotic diversity for environmental monitoring of offshore oil-drilling activities.
abstract: As global exploitation of available resources increases, operations extend towards sensitive and previously protected ecosystems. It is important to monitor such areas in order to detect, understand and remediate environmental responses to stressors. The natural heterogeneity and complexity of communities means that accurate monitoring requires high resolution, both temporally and spatially, as well as more complete assessments of taxa. Increased resolution and taxonomic coverage is economically challenging using current microscopy-based monitoring practices. Alternatively, DNA sequencing-based methods have been suggested for cost-efficient monitoring, offering additional insights into ecosystem function and disturbance. Here, we applied DNA metabarcoding of eukaryotic communities in marine sediments, in areas of offshore drilling on the Norwegian continental shelf. Forty-five samples, collected from seven drilling sites in the Troll/Oseberg region, were assessed, using the small subunit ribosomal RNA gene as a taxonomic marker. In agreement with results based on classical morphology-based monitoring, we were able to identify changes in sediment communities surrounding oil platforms. In addition to overall changes in community structure, we identified several potential indicator taxa, responding to pollutants associated with drilling fluids. These included the metazoan orders Macrodasyida, Macrostomida and Ceriantharia, as well as several ciliates and other protist taxa, typically not targeted by environmental monitoring programmes. Analysis of a co-occurrence network to study the distribution of taxa across samples provided a framework for better understanding the impact of anthropogenic activities on the benthic food web, generating novel, testable hypotheses of trophic interactions structuring benthic communities.
authors.affiliation: Department of Conservation of Natural Resources, NEIKER Tecnalia, Bizkaia Technology Park, 48160, Derio, Spain.
authors.forename: Anders
authors.initials: A
authors.lastname: Lanzén
authors.affiliation: Department of Biology, University of Bergen, Box 7800, 5020, Bergen, Norway.
authors.forename: Katrine
authors.initials: K
authors.lastname: Lekang
authors.affiliation: Computational Biology Unit, Department of Informatics, University of Bergen, Bergen, Norway.
authors.forename: Inge
authors.initials: I
authors.lastname: Jonassen
authors.affiliation: Department of Biology, University of Bergen, Box 7800, 5020, Bergen, Norway.|Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway.|Uni Research Environment, Uni Research AS, 5020, Bergen, Norway.
authors.forename: Eric M
authors.initials: EM
authors.lastname: Thompson
authors.affiliation: Uni Research Environment, Uni Research AS, 5020, Bergen, Norway.
authors.forename: Christofer
authors.initials: C
authors.lastname: Troedsson
mesh_terms: D000818:Animals; D044822:Biodiversity; D016798:Ciliophora; D058893:DNA Barcoding, Taxonomic; D017753:Ecosystem; D004784:Environmental Monitoring; D020387:Food Chain; D019015:Geologic Sediments; D061329:Oil and Gas Fields
keywords: DNA barcoding; bioinformatics/phyloinformatics; foodwebs; microbial biology