Document of bibliographic reference 339553

BibliographicReference record

Type

Bibliographic resource

Type of document

Journal article

BibLvlCode

AS

Title

Long-term response of marine benthic fauna to thin-layer capping with powdered activated carbon in the Grenland fjords, Norway

Abstract

The Grenland fjords in Norway have a long history of contamination by large emissions of dioxins and mercury. As a possible sediment remediation method in situ, thin-layer capping with powdered activated carbon (AC) mixed with clay was applied at two test sites at 30 m and 95 m depth in the Grenland fjords. This study presents long-term effects of the AC treatment on the benthic community structure, i.e. nine years after capping. Capping with AC significantly reduced the number of species, their abundance and biomass at the two test sites, compared to uncapped reference sites. At the more shallow site, the dominant brittle star species Amphiura filiformis disappeared shortly after capping and did not re-establish nine years after capping. At the deeper site, the AC treatment also caused long-lasting negative effects on the benthic community, but some recovery was observed after nine years. Ecological indices used to assess environmental status did not capture the impaired benthic communities caused by the capping. The present study is the first documentation of negative effects of powdered AC on marine benthic communities on a decadal scale. Our results show that the benefits of reduced contaminant bioavailability from capping with AC should be carefully weighed against the cost of long-term detrimental effects on the benthic community. More research is needed to develop a thin-layer capping material that is efficient at sequestering contaminants without being harmful to benthic species.

WebOfScience code

https://www.webofscience.com/wos/woscc/full-record/WOS:000647601800005

Bibliographic citation

Trannum, H.C.; Raymond, C.; Næss, R.; Borgersen, G.; Gunnarsson, J.S.; Schaanning, M.T. (2021). Long-term response of marine benthic fauna to thin-layer capping with powdered activated carbon in the Grenland fjords, Norway. Sci. Total Environ. 776: 145971. https://dx.doi.org/10.1016/j.scitotenv.2021.145971

Topic

Marine

Is peer reviewed

true

Access rights

open access

Is accessible for free

true