WP5: Methods to assess environmental impacts and recovery potential

The main objective was to assess the impact of mining activities and the recovery potential of vent ecosystems in the AMOR. In this work the focus was on the inactive Mohns Treasure, 35 km away from the active Loki’s Caslte hydrothermal vent field. A full ROV survey was conducted at 3 different sites on the Mohns Treasure area. The results indicate that this region is characterised by a soft sediment seafloor with rocky outcrops. The fauna is typical from abyssal habitats, with the rocks colonised by dense aggregations of sponges and their associated fauna (e.g. shrimp, crinoids), while the sediment hosted stalked crinoids (sea lillies), small elasipodid holothurians, sparse seastars and some benthopelagic fish. Of particular interest were the vast fields of stalked crinoids, mostly in the deeper area (2700 m), as crinoids are indicators of Vulnerable Marine Ecosystems, which would have to be considered in any environmental impact assessment and management decision of mining activities in the region. A paper describing the Mohn’s Treasure ecosystem will be submitted to Frontiers in Marine Science by the end of November 2019. We are also developing a biophysical model of population connectivity for key vent species from Loki’s Castle. Understanding population connectivity and source-sink metapopulation dynamics is essential in spatial management, particularly for patchy ecosystems such as hydrothermal vents.

Sediment habitat with an asteroid (A) and foraminifera shell accumulation below a rock (B).

Table 1 Project resources

Work package Leader Contributors
Sample identification and collection Martin Ludvigsen Øystein Sture
Mineral processing options for submarine massive sulphide ores Rolf Arne Kleiv Przemyslaw B. Kowalczuk


Conceptual study of Methods for Extraction of Marine Minerals Steinar L. Ellefmo Maxime Lesage


Characterization Kurt Aasly Ben Snook
Methods to assess environmental impacts and recovery potential Eva Ramirez-Llodra Ana Hilario

Amanda Kieswetter

Emil Paulsen