MEPS 506:61-70 (2014)  -  DOI: https://doi.org/10.3354/meps10778

Length, strength and water flow: relative importance of wave and current exposure on morphology in kelp Laminaria hyperborea

Trine Bekkby1,2,*, Eli Rinde1, Hege Gundersen1,3, Kjell Magnus Norderhaug1,4, Janne K. Gitmark1, Hartvig Christie1

1Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349 Oslo, Norway
2Geo-Ecology Research Group, Natural History Museum, and 3Centre for Ecological and Evolutionary Synthesis (CEES), and 4Department of Biosciences, University of Oslo, 0316 Oslo, Norway
*Corresponding author:

ABSTRACT: Water flow is a strong determinant of kelp growth, but it is also a stress factor causing breakage and dislodgement. As wave exposure and currents differ with respect to flow pattern, the 2 forces are expected to affect kelp morphology differently. We investigated how wave exposure and current speed interact and influence kelp Laminaria hyperborea morphology. We sampled thalli from 27 stations on the Midwest coast of Norway and recorded age, and length- and strength-related characters. We found that high wave exposure and current speed influenced holdfast biomass and stipe thickness. Wave exposure had, overall, a stronger effect than current speed. An increase in current speed seemed to have a considerable effect at low wave exposure levels, but the relationship weakened at high wave exposure levels. The length-related (‘go with the flow’) characters thallus and stipe length were influenced by wave induced water flow but not by current speed. Differences in wave exposure and current speed had very weak influences on lamina biomass and length. Thus, the proportion of the thallus being lamina was high in the most sheltered areas and decreased as the wave exposure increased. Our study suggests that the strong, orbital and stochastic mode of wave exposure has a different and stronger effect as a stressor than the more regular and bidirectional stress caused by currents. 


KEY WORDS: Physical disturbance · Stress · Water flow · Kelp morphology · Biomass · Size


Full text in pdf format 
Supplementary material 
Cite this article as: Bekkby T, Rinde E, Gundersen H, Norderhaug KM, Gitmark JK, Christie H (2014) Length, strength and water flow: relative importance of wave and current exposure on morphology in kelp Laminaria hyperborea. Mar Ecol Prog Ser 506:61-70. https://doi.org/10.3354/meps10778

Export citation
Mail this link - Contents Mailing Lists - RSS
- -