Abstract
Along the Norwegian coastline, it is predicted that salmonid aquaculture will rapidly expand in the coming years, exceeding current production levels of 1.3 million t in 2012. This will result in increased interactions with both local and regional environments, thus more knowledge is urgently needed to better risk-manage a rapid expansion. We investigated changes in the ben- thic sediment condition in association with an Atlantic salmon farm sited at a deep, well-flushed coastal site in western Norway. Benthic fluxes of O2, total carbon dioxide (TCO2) and NH4 + inten- sified over the production cycle, when farming activity and the sedimentation of carbon and nitro- gen was at its maximum. During the sampling campaign, benthic fluxes of O2, TCO2 and NH4 + at the farming location were higher than those measured at a nearby reference location. Stimulation of benthic fluxes over the production cycle at the farming location were most likely driven by changes in benthic faunal community structure, abundance and biomass. High abundances of opportunistic species (i.e. Capitella capitata, Heteromastus filiformis, Paramphinome jeffreysii, Abra nitida and Thyasira sarsii) dominated the farming location, whilst the sediment biogeochem- istry was stable throughout the study period at both locations. However, despite differences in benthic fluxes and fauna structure over the production cycle, the input of organic carbon and nitrogen did not exceed the mineralisation capacity of a deep, well-flushed, fish farming location.
Highlights
Global aquaculture production (63.6 million t annually) accounts for more than 41% of total world fisheries, and is important for meeting the global demand for protein
We aimed to investigate temporal-scale changes in total sediment metabolism, sediment metabolic pathways and benthic infauna community composition to establish a holistic understanding of the interaction of increased organic carbon deposition from fin-fish aquaculture at a wellflushed deep-water coastal site in a Norwegian fjord
Sedimentation rates and organic enrichment. At this well-flushed fish farm, ~340 t of organic waste was released directly to the surrounding environment over the production cycle and at peak production (June to September 2010), daily sedimentation rates of particulate organic carbon (POC) ranged between 1.4 and 2.0 g m−2 at the farming location. These sedimentation rates are comparable to those measured by Kutti et al (2007a) at another deep-water salmon farm in Norway, and with predicted values calculated by Keeley et al (2013a) at moderately enriched shallow-water salmon farms in New Zealand
Summary
Global aquaculture production (63.6 million t annually) accounts for more than 41% of total world fisheries (capture and production; FAO 2012), and is important for meeting the global demand for protein. The intensive farming of fin fish in net pens releases organic and inorganic effluents (i.e. carbon, nitrogen and phosphorus) in the form of waste feed, faeces and metabolic by-products to the surrounding aquatic marine environments (Carroll et al 2003, Holmer et al 2005, Strain & Hargrave 2005). Accumulation of these effluents can contribute to eutrophication and nutrient enrichment of pelagic systems and cause organic enrichment of the benthic environment (Strain & Hargrave 2005).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
