Haruto Ishii

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Distribution and biomass of salps and Antarctic krill (Euphausia superba) were investigated near the South Shetland Islands during austral summer 1990–1991. Salp biomass ranged between 0 and 556 mgC·m−3 and was greatest at a station in the Bransfield Strait in late December 1990. Salp biomass was lower than that of E. superba. Two species of salps; Salpa(More)
Tokyo Bay is one of the most eutrophicated bays in Japan, and mass occurrences of scyphozoan jellyfish Aurelia aurita have often been observed with progress of eutrophication. In the coastal environment, the abundance of substrates suitable for A. aurita polyps are obviously increasing by reclamation. However, most suitable substrates for settling, except(More)
In situ seasonal variations in stomach contents of Aurelia aurita (L.) in Tokyo Bay, Japan, were analyzed. Copepods, such as Oithona davisae Ferrari & Orsi were the predominant food items of A. aurita from June to November. The mean digestion time measured in incubation experiments was 0.95 h. Daily rations calculated using stomach content data and(More)
The phyllosoma, a larva of spiny and slipper lobsters, has an exceptionally flat body and long appendages. It is known to associate with several species of cnidarian jellyfish, a behavior that is not rare in crustaceans. Indeed, phyllosomas clinging onto jellyfish have been observed both in the laboratory and in the natural environment. Wild phyllosomas(More)
Chitosan-amino acid conjugates were prepared by coupling amino acid esters to the carboxyl group of glyoxylic acid-substituted chitosan. The removal of heavy metals (Cu, Ni, Co and Mn) was increased by introduction of amino acids to chitosan, especially for Mn. Heavy metals were almost completely removed by chitosan-amino acid conjugates from solutions at(More)
The continuous changes in the number of newly established polyps of Aurelia aurita (L.) on settling plates under natural conditions were observed from August 1998 to September 1999 in Tokyo Bay, Japan. A sharp decline in survivorship of newly settled polyps was observed within the first few days, however, survivorship of polyps settled in October increased(More)
Although jellyfish are important predators of fish larvae, many fish species also feed on jellyfish. Therefore, the predator–prey role of jellyfish and fish may switch during the course of their life histories. Here, we investigated such interactions by examining (1) the avoidance behaviour of threadsail filefish Stephanolepis cirrhifer to moon jellyfish(More)
ISSN: 0916-8451 (Print) 1347-6947 (Online) Journal homepage: http://www.tandfonline.com/loi/tbbb20 Heavy Metal Uptake by Swollen Chitosan Beads Tomayo Mitani, Ayumi Moriyama & Hiroshi Ishii To cite this article: Tomayo Mitani, Ayumi Moriyama & Hiroshi Ishii (1992) Heavy Metal Uptake by Swollen Chitosan Beads, Bioscience, Biotechnology, and Biochemistry,(More)
To identify new biopolymer-degrading enzymes produced from cold-adapted microorganisms, we searched for such enzymes in bag filters used for the purification of deep seawater pumped up in Sagami Bay, Japan. We isolated a casein- and azocoll-degrading cold-adapted bacterium, and it was identified as Vibrio species Pr21. The bacterium grew between 0 and 25(More)
Biogenic silica (BSi), lithogenic silica (LSi), particiulate organic carbon (POC) and nitrogen (PON), and chlorophyll a (Chl a) concentration levels were measured in the surface waters (<100 m) off the northern coast of the South Shetland Islands in summer 1991. High concentration levels of BSi and LSi were recorded in the oceanic area and the coastal area,(More)
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