Impaired short-term functioning of a benthic community from a deep Norwegian fjord following deposition of mine tailings and sediments

Lisa Mevenkamp*, Tanja Stratmann, Katja Guilini, Leon Moodley, Dick van Oevelen, Ann Vanreusel, Stig Westerlund, Andrew K Sweetman

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

17 Citations (Scopus)
87 Downloads (Pure)


The extraction of minerals from land-based mines necessitates the disposal of large amounts of mine tailings. Dumping and storage of tailings into the marine environment, such as fjords, is currently being performed without knowing the potential ecological consequences. This study investigated the effect of short-term exposure to different deposition depths of inert iron ore tailings (0.1, 0.5, and 3 cm) and dead subsurface sediment (0.5 and 3 cm) on a deep water (200 m) fjord benthic assemblage in a microcosm experiment. Biotic and abiotic variables were measured to determine structural and functional changes of the benthic community following an 11 and 16 day exposure with tailings and dead sediment, respectively. Structural changes of macrofauna, meiofauna, and bacteria were measured in terms of biomass, density, community composition and mortality while measures of oxygen penetration depth, sediment community oxygen consumption and 13C-uptake and processing by biota revealed changes in the functioning of the system. Burial with mine tailings and natural sediments modified the structure and functioning of the benthic community albeit in a different way. Mine tailings deposition of 0.1 cm and more resulted in a reduced capacity of the benthic community to remineralize fresh 13C-labeled algal material, as evidenced by the reduced sediment community oxygen consumption and uptake rates in all biological compartments. At 3 cm of tailings deposition, it was evident that nematode mortality was higher inside the tailings layer, likely caused by reduced food availability. In contrast, dead sediment addition led to an increase in oxygen consumption and bacterial carbon uptake comparable to control conditions, thereby leaving deeper sediment layers anoxic and in turn causing nematode mortality at 3 cm deposition. This study clearly shows that even small levels (0.1 cm) of instantaneous burial by mine tailings may significantly reduce benthic ecosystem functioning on the short term. Furthermore, it reveals the importance of substrate characteristics and origin when studying the effects of substrate addition on marine benthic fauna. Our findings should alert decision makers when considering approval of new deep-sea tailings placement sites as this technique will have major negative impacts on benthic ecosystem functioning over large areas.

Original languageEnglish
Article number169
JournalFrontiers in Marine Science
Publication statusPublished - 30 May 2017


  • C-labeling
  • Algal carbon
  • Anthropogenic disturbance
  • Benthos
  • Deep sea
  • Pulse-chase analysis
  • Submarine tailings placement

ASJC Scopus subject areas

  • Oceanography
  • Global and Planetary Change
  • Water Science and Technology
  • Ocean Engineering
  • Aquatic Science


Dive into the research topics of 'Impaired short-term functioning of a benthic community from a deep Norwegian fjord following deposition of mine tailings and sediments'. Together they form a unique fingerprint.

Cite this