Impact of returning scientific cruises and prolonged on-site presence on litter abundance at the deep-sea nodule fields in the Peru Basin

Mar Pollut Bull. 2022 Nov:184:114162. doi: 10.1016/j.marpolbul.2022.114162. Epub 2022 Sep 26.

Abstract

Marine litter can be found along coasts, continental shelves and slopes, down into the abyss. The absence of light, low temperatures and low energy regimes characterising the deeper habitats ensure the persistence of litter over time. Therefore, manmade items within the deep sea will likely accumulate to increasing quantities. Here we report the litter abundance encountered at the Pacific abyssal nodule fields from the Peru Basin at 4150 m depth. An average density of 2.67 litter items/ha was observed. Litter composed of plastic was the most abundant followed by metal and glass. At least 58 % of the items observed could be linked to the research expeditions conducted in the area and appeared to be mostly accidental disposals from ships. The data gathered was used to address temporal trends in litter abundance as well as the impact of human on-site presence and return cruises in the context of future deep-sea mining efforts.

Keywords: Abyss; Deep sea; Human impacts; Litter; Marine debris.

MeSH terms

  • Ecosystem
  • Environmental Monitoring*
  • Humans
  • Mediterranean Sea
  • Metals / analysis
  • Peru
  • Plastics*
  • Waste Products / analysis

Substances

  • Plastics
  • Metals
  • Waste Products