- 著者
- Tatsuya Ishikawa Akira Kurashima
- 出版者
- The Plankton Society of Japan, The Japanese Association of Benthology
- 雑誌
- Plankton and Benthos Research (ISSN:18808247)
- 巻号頁・発行日
- vol.15, no.2, pp.112-120, 2020-05-27 (Released:2020-05-30)
- 参考文献数
- 50
- 被引用文献数
- 3
This study aimed to estimate the feeding pressure of a Diadema setosum population on a barren ground in Kata Bay, Mie Prefecture, Japan, which is a temperate region. We combined data of the feeding rate of D. setosum from tank experiments and of the D. setosum population dynamics obtained from monthly surveys. We conducted tank experiments to clarify the relationships between the feeding rate of D. setosum and the water temperature and test diameter of the sea urchins. The feeding rate and water temperature were positively correlated over the range of 15°C to 30°C. The test diameter composition of the D. setosum population in Kata Bay was stable throughout the study period (June 2014 to May 2015). The results revealed distinct seasonal changes in the feeding pressure of the D. setosum population owing to temperature variations.
5 0 0 0 OA Effect of sea urchin (Diadema setosum) density on algal composition and biomass in cage experiments
- 著者
- Tatsuya Ishikawa Miyuki Maegawa Akira Kurashima
- 出版者
- 日本プランクトン学会、日本ベントス学会
- 雑誌
- Plankton and Benthos Research (ISSN:18808247)
- 巻号頁・発行日
- vol.11, no.4, pp.112-119, 2016-11-25 (Released:2016-11-23)
- 参考文献数
- 30
- 被引用文献数
- 13
This study examines the effects of the sea urchin Diadema setosum on algal composition, coverage and biomass on barren ground. In cage experiments, the effects of D. setosum density were examined at 5 levels over the range of 0–8 ind. m−2. Algal coverage and number of species, densities and lengths of Sargassum spp. on experimental blocks in each cage were measured monthly. In the cage without D. setosum, algal coverage and biomass were higher than in cages with D. setosum. For D. setosum density of 1 ind. m−2 and higher, decreased algal coverage and decreased biomass and density of Sargassum spp. were observed. D. setosum at a density higher than 2 ind. m−2 had a negative effect on algal species numbers. Consequently, algae could grow when the D. setosum density was fewer than 2 ind. m−2. This study revealed that grazing by D. setosum has a great effect on the seaweed bed ecosystems along the coast of central Japan.