Proximate Composition and Standing Crop of Durvillaea-Antarctica (Pheophyta) in the Bay of Morbihan, Kerguelen (South Indian-Ocean)

• Published in: Marine Ecology Progress Series
• Main Author: Lawrence, John M.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Digital Commons @ University of South Florida 1986
• Subjects: Medical Sciences; Medicine and Health Sciences; Holdfast; Indian; Kerguelen; Antarc*; Antarctica; antartic*
• Online Access: https://digitalcommons.usf.edu/bin_facpub/25; https://doi.org/10.3354/meps033001

The proximate composition (% dry weight) of Durvillaea antartica (Cham.) Hariot was similar for the frond and stipe, being 28 % ash, 3 % protein, ca 1 % lipid, less than 10 % acid-soluble carbohydrate, and 60 % acid-insoluble carbohydrate. The holdfast differed by being 22 % ash and 66 % acid-insoluble carbohydrate. The energetic level of all 3 components was ca 13 kJ (g dry wt)-1 and ca 17 kJ (g ash-free dry wt)-1. The relative proportion of the 3 plant components varied little for plants having stipe diameters ranging from 10 to 40 mm, being ca 8, 3, and 89 % wet wt and ca 10, 4, and 86 % kJ for the holdfast, stipe, and frond, respectively. Maximal density found in summer was 471 individual plants m-2, 226 kg wet wt m-2, and 457,000 kJ m-2. Juvenile plants dominated in terms of individuals, but adults were more important in gravimetric and energetic units. D. antarctica allocates most of its biomass and energy to the frond throughout its size range. The characteristics of D. antarctica in the Bay of Morbihan are those for a sheltered shore.