Abstract
Drag force was measured on individual specimens of Hedophyllum sessile in a variable-speed flow tank. Those from sheltered localities, which are broad, bullate blades, experience greater drag at a given water velocity than ones from localities more exposed to the action of waves, which have smooth, deeply dissected blades. All specimens rearranged their blades as water velocity increased, resulting in a decrease in effective drag at higher water speeds, but individuals with smooth, dissected blades assumed a more compact shape at high current speeds and thus reduced their effective drag over that of broad-bladed individuals at the same speed. In habitats chronically exposed to strong wave action, drag reduction may be an important survival mechanism; in calm habitats the turbulence induced by lack of such streamlining may enhance mixing of the water in the immediate vicinity of a plant.
Similar content being viewed by others
References
Abbott, I. A. & G. J. Hollenberg, 1976. Marine Algae of California. Stanford University Press, Stanford, CA 827 pp.
Armstrong, S. L., 1984. Functional morphology and tissue mechanics of the brown alga Hedophylum sessile. Doctoral dissertation, Duke University, Durham, NC. 106 pp.
Charters, A. C., M. Neushel & C. Barilotti, 1969. The functional morphology of Eisenia arborea. Proc. Int. Seaweed Symp. 6: 89–105.
Daniel, T. L., 1981. Fish mucus: In situ measurements of polymer drag reduction. Biol. Bull. 160: 376–382.
Dayton, P. K., 1975. Experimental evaluation of ecological dominance in a rocky intertidal algal community. Ecol. Monogr. 45: 137–159.
Hoyt, J. W., 1970. High molecular weight algal substances in the sea. Mar. Biol. 7: 93–99.
Mathieson, A. C., T. A. Norton & M. Neushel, 1981. The taxonomic implications of genetic and environmentally induced variations in seaweed morphology. Bot. Rev. 47: 313–347.
Norton, T. A., A. C. Mathieson & M. Neushel, 1981. Morphology and environment. In The Biology of Seaweeds, C. S. Lobban and M. J. Wynne, eds. Botanical Monographs 17. University of California Press, Berkeley: 421–451.
Norton, T. A., A. C. Mathieson & M. Neushel, 1982. A review of some aspects of form and function in Seaweeds. Bot. Mar. 25: 501–510.
Scagel, R. F., 1967. Guide to the Common Seaweeds of British Columbia. British Columbia Provincial Museum, Victoria, B. C. Handbook No. 27.
Svendsen, P. & J. M. Kain, 1971. The taxonomic status, distribution, and morphology of Laminaria cucullata sensu Jorde and Klavestad. Sarsia 46: 1–22.
Vogel, S., 1984. Drag and flexibility in sessile organisms. Am. Zool. 24: 37–44.
Vogel, S. & M. LaBarbera, 1978. Simple flow tanks for research and teaching. Bioscience 28: 638–643.
Wheeler, W. N., 1980. Effect of boundary layer transport on the fixation of carbon by the giant kelp Macrocystis pyrifera. Mar. Biol. 56: 103–110.
Widdowson, T. B., 1965. A taxonomic study of the genus Hedophyllum Setchell. Can. J. Bot. 43: 1409–1420.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Armstrong, S.L. The behavior in flow of the morphologically variable seaweed Hedophyllum sessile (C. Ag.) Setchell. Hydrobiologia 183, 115–122 (1989). https://doi.org/10.1007/BF00018716
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00018716