Annelids in coastal organic-rich habitats
As one of the most common marine animal groups, small worms belonging to the annelids are often used to monitor the state of the ocean environment. In this project we will try to disentangle problems with some often used species names.
Reduced organic-rich environments in coastal waters are a natural part of a complex sea-shore boundary with deep fjords and narrow sounds, such as the Norwegian coastline. High biological production, freshwater run off and deep basins allow for high organic loads to deep stagnant waters where oxygen levels quickly drop.
These habitats have a naturally occurring fauna that to some extent is shared with naturally occurring faunal assemblages at vents, seeps and whale falls as well as anthropogenic disturbed sediments at sewage discharges, pulp mills and aquaculture. The fauna assemblages at organic-rich environments conduct important ecosystem services in providing remineralisation of organic carbon and thus facilitate organic carbon recycling.
In an effort to understand and control the impact on the coastal environment, regular monitoring of faunal diversity and abundance are required by the authorities. Samples of benthic fauna are taken at the site of impact as well as at reference sites. A considerable volume of data on species occurrence in organic-rich habitats along the Norwegian coast has been accumulated in this monitoring effort. A preliminary analysis of a sample of these data suggest that a great number of the species names used are problematic and that these taxa require revision based e.g. on molecular data.
Project leader: Thomas Dahlgren, Uni Research
Project period: January 2015 – December 2017
Collaborating partners: University of Bergen, Natural History Museum in London and Institute of Marine Research