TEMPERATURE TOLERANCE OF NORTHEAST PACIFIC MARINE ALGAE 1

• Published in: Journal of Phycology
• Main Authors: Lüning, Klaus, Freshwater, Wilson
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1988
• Subjects: North Atlantic
• Online Access: http://dx.doi.org/10.1111/j.1529-8817.1988.tb04471.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1529-8817.1988.tb04471.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1529-8817.1988.tb04471.x

ABSTRACT Temperature tolerance (1 week exposure time) was investigated in 49 species of benthic marine macroalgae and two seagrass species from San Juan Island (Washington) or Vancouver Island, British Columbia. Positive net photosynthesis was the parameter used to detect survival. Most algal species survived ‐1.5° C (the lowest applied temperature), and none 30° C. The most heat‐tolerant, eurythermal algal species survived 28° C: these were Ahnfeltia plicata, Mastocarpus papillatus (as crustose tetrasporophyte), Endocladia muricata, and Sargassum muticum. In contrast, most representatives of the Laminariales exhibited a cold‐stenothermic character: Cymathere triplicata, Pleurophycus gardneri, Hedophyllum sessile, Postelsia palmaeformis survived up to only 15° C, and Laminaria saccharina, L. groenlandica, L. setchellii to 18° C. As to the seagrass species, Zostera marina survived a temperature range of ‐ 1.5 to 30° C and Phyllospadix scouleri a range of ‐ 1.5 to 25° C. For many of the sublittoral species there was agreement between maximum survived temperatures in our experiments and average maxima of summer temperatures at the southern geographical limits of the species. Specimens of four species exhibited upper survival limits similar to those of conspecifics in the North Atlantic; namely, Desmarestia ‘aculeata, D. viridis, Plocamium cartilagineum, and Ahnfeltia plicata. These results favor the interpretation of upper temperature survival limits as conservative taxonomic traits.