Inter-Research > AEI > v12 > p117-129  
Aquaculture Environment Interactions

via Mailchimp

AEI 12:117-129 (2020)  -  DOI:

Effect of substrate type and pellet age on the resuspension of Atlantic salmon faecal material

M. A. Carvajalino-Fernández1,2,*, N. B. Keeley1, I. Fer2, B. A. Law3, R. J. Bannister1

1Institute of Marine Research, 5817 Bergen, Norway
2Geophysical Institute, University of Bergen, 5020 Bergen, Norway
3Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia B2Y 4A2, Canada
*Corresponding author:

ABSTRACT: The influence of substrate type and particle age on the remobilization of settled Atlantic salmon Salmo salar faecal material was studied through a set of controlled experiments in horizontal flow flumes, simulating different bottom conditions present in fish-farming locations along the coast of Norway. There was no significant effect of pellet age on remobilization for up to 1 week old faecal material, but critical shear stresses (τc) and velocities required for resuspending faecal pellets were strongly dependent on substrate type. Smooth substrates such as mud and rock slate required lower stresses for the onset of faeces resuspension (τc ≈ 0.06 Pa) than rougher surfaces such as sand (τc ≈ 0.12 Pa) or fragmented rock (τc ≈ 0.32 Pa), where bedforms and large fractures shield the particles from the direct influence of the drag forces. These newly determined substrate-dependent τc resuspension thresholds will contribute to the construction of more accurate numerical models that include bottom type as a parameter regulating the extent of particle spreading, in contrast to the constant-value approach that has been used to date.

KEY WORDS: Benthic boundary layer · Resuspension · Parametrization

Full text in pdf format 
Cite this article as: Carvajalino-Fernández MA, Keeley NB, Fer I, Law BA, Bannister RJ (2020) Effect of substrate type and pellet age on the resuspension of Atlantic salmon faecal material. Aquacult Environ Interact 12:117-129.

Export citation
RSS - Facebook - - linkedIn