Productivity of a Sargassum macrocarpum (Fucales, Phaeophyta) population in Fukawa Bay, Sea of Japan

Abstract

SUMMARY: The productive structure and productivity of a Sargassum macrocarpum C. Agardh population were studied from June 1993 to July 1994 in Fukawa Bay facing the Sea of Japan, Yamaguchi Prefecture. S. macrocarpum formed a dense population at a depth of 8 m in the study area. Using the stratified clip technique, monthly changes in the productive structure from 1993 to 1994 were clarified. The dry weight of leaves and main branches increased with the elongation of branches. Thalli in the middle to high stratum began to bear receptacles from March 1994 and the dry weight of receptacles was approximately one‐third of the standing crop in June. The loss of leaves increased from April to June 1994, and the loss of main branches and receptacles from June to July 1994. Productivity of branches and receptacles reached maxima of 4.67 g dry wt/m2 per day from February to March and 5.33 g dry wt/m2 per day from April to May, respectively. Productivity of the leaves, however, was almost constant at approximately 2 g dry wt/m2 per day from July 1993 to March 1994. Therefore, maximum productivity of the S. macrocarpum population of 7.17 g dry wt/m2 per day occurred from February to March. Annual net production of newly sprouting branches in June 1993 was 1600.1 g dry wt/m2 per year based on the summation method, which was calculated from the monthly changes in the productive structure.

Seasonal population dynamics of Sargassum fusiforme (Fucales, Phaeophyta), Suo-Oshima Is., Seto Inland Sea, Japan—development processes of a stand characterized by high density and productivity

“…As the seasonal population development of S. fusiforme in our study was similar to the populations in the Pacific region, the recruits we observed were considered to be ramets and they mainly contributed to maintain the population as the previous studies have indicated (Suto 1951; Arai and Arai 1983). Biomass allocation of receptacles relative to the total biomass at the seasonal peak of maturation was lower in S. fusiforme in this study (14 %) than those in other Sargassum species reported so far, e.g., 20–24 % in Sargassum muticum (Yendo) Fensholt (Arenas and Fernández 1998) and 34 % in Sargassum macrocarpum C. Agardh (Murase et al 2000), also indicating the relative importance of vegetative reproduction in S. fusiforme .…”

Diversity, biomass and distribution pattern of Sargassum beds in the South West lagoon of New Caledonia (South Pacific)

“…All these studies reported highest biomass for Sargassum during cool periods. Conversely, Murase et al (2000) reported the highest S. macrocarpum productivity during summer in Japan, and Kilar and Norris (1988) did not detect any clear seasonal pattern in S. filipendula from Caribbean Panama.…”

Zygote-derived seedling production of Sargassum thunbergii: focus on two frequently experienced constraints in tank culture of seaweed

“…O. Kuntze is a common species in the rocky intertidal zone along the western North Pacific (Phillips 1995). This alga plays important ecological roles in the coastal ecosystem due to the large biomass and high productivity (Murae et al 2000). Because of its potentials in alginate production and bioactive extraction, S. thunbergii is also of great economic importance.…”