Effects of mussel farms on the benthic nitrogen cycle on the Swedish west coast

MS Carlsson, P Engström, O Lindahl, L Ljungqvist, Jens Kjerulf Petersen, L Svanberg, Marianne Holmer

    Research output: Contribution to journalJournal articleResearchpeer-review

    Abstract

    The biogeochemical impact of 3 long-line mussel farms (M1, M2 and M3) in Lysekil, Sweden, was investigated from before farm establishment until 1.5 yr after operation had begun. Sedimentation, benthic N flux, total oxygen uptake (TOU) and sulfate reduction rate (SRR) were all significantly increased below the mussel lines at all 3 farms. Effects of increased sedimentation rates were revealed by sediment profile imaging and were highest at Stn M2. These effects increased significantly with time of farm operation, indicating the accumulation of organic matter within sediments over time. Furthermore, more total particulate organic N deposited at farm stations was recycled into the water column compared to at reference stations (~45 versus ~13%), indicating an increased release of dissolved inorganic N from sediment below the mussel farms. At one station (M2) with the highest increase in sedimentation rate, denitrification seemed inhibited, while at another station (M3), with a less pronounced increase in sedimentation rate, denitrification was in fact stimulated, accounting for 13% of total sediment N removal. Calculations based on estimated values of N removal through mussel harvest and direct measurements of N input through changes in sedimentation, N regeneration from sediment to the water column through benthic fluxes and changes in denitrification showed, in all cases, a net removal of N from the system, as only 26 to 40% of the total amount of harvested N had been added to the sediments during the growth period.
    Original languageEnglish
    JournalAquaculture Environment Interactions
    Volume2
    Issue number2
    Pages (from-to)177-191
    ISSN1869-215X
    DOIs
    Publication statusPublished - 2012

    Fingerprint Dive into the research topics of 'Effects of mussel farms on the benthic nitrogen cycle on the Swedish west coast'. Together they form a unique fingerprint.

    Cite this