Floating seaweed and the influences of temperature, grazing and clump size on raft longevity: a microcosm study
Vandendriessche, S.; Vincx, M.; Degraer, S. (2007). Floating seaweed and the influences of temperature, grazing and clump size on raft longevity: a microcosm study, in: Vandendriessche, S. Drijvend zeewier als efemeer neustonisch habitat = Floating seaweed as ephemeral neustonic habitat. pp. 99-112 In: Vandendriessche, S. (2007). Drijvend zeewier als efemeer neustonisch habitat = Floating seaweed as ephemeral neustonic habitat. PhD Thesis. Universiteit Gent. Faculteit Wetenschappen: Gent. X, 145 pp., more Related to:Vandendriessche, S.; Vincx, M.; Degraer, S. (2007). Floating seaweed and the influences of temperature, grazing and clump size on raft longevity: a microcosm study. J. Exp. Mar. Biol. Ecol. 343(1): 64-73. https://dx.doi.org/10.1016/j.jembe.2006.11.010, more |
Keywords | Behaviour > Feeding behaviour > Grazing Floating Flora > Weeds > Marine organisms > Seaweeds Properties > Physical properties > Thermodynamic properties > Temperature Ascophyllum nodosum (Linnaeus) Le Jolis, 1863 [WoRMS]; Fucus vesiculosus Linnaeus, 1753 [WoRMS]; Idotea baltica Pallas, 1772 [WoRMS] Marine/Coastal | Author keywords | floating seaweed; grazing; North Sea; temperature |
Abstract | Laboratory experiments were conducted to evaluate the longevity, and consequently also the rafting capacity of the brown seaweeds Fucus vesiculosus and Ascophyllum nodosum. The seaweed degradation process and the activity of the grazer Idotea baltica were strongly influenced by temperature: only at 5 °C, the seaweed growth exceeded the weight loss. At higher temperatures, seaweed fragments sank quickly (within 100 days at temperatures higher than 15 °C). This process was significantly accelerated in the presence of I. baltica, resulting in a decrease of raft longevity of 60-70%. At a constant temperature of 15 °C and in the absence of grazers, fragments of A. nodosum floated longer (mean 45 weeks) than fragments of F. vesiculosus (mean 15 weeks). The results indicate that floating seaweeds have the potential to stay afloat for a long time, but that their longevity is temperature-dependent and can be strongly reduced by grazing activity of associated herbivores. |
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