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Volume 54, Issue 3
Displaying 1-7 of 7 articles from this issue
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Teruo ISHIDA1993 Volume 54 Issue 3 Pages 163-169
Published: July 28, 1993
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSHalicyclops sinensis, known from China, and Paracyclops poppei are recorded for the first time from Japan. Halicyclops japonicus, known only from a small island on the Sea of Japan, and Bryocamptus laccophilus, known from Europe and Erimo, Hokkaido, are reported from Yakushima Island. Ochridacyclops sp., known from Kyusyu, is reported from Shikoku and Hokkaido. Some illustrations for help in diagnosis of these species and a discussion of their distribution are presented.View full abstractDownload PDF (461K) -
Yuichi MIYABARA, Hiroshi WATANABE, Junzo SUZUKI, Shizuo SUZUKI1993 Volume 54 Issue 3 Pages 171-178
Published: July 28, 1993
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSInhibitory effects of tetrapyrrole compounds upon alkaline or acid phosphatase of lake water, phytoplankton, and authentic enzymes were investigated. Alkaline phosphatase activity from three sources was inhibited with bilirubin, biliverdin, mesopor-phyrin, chlorophyllin and urobilin. However, inhibiting rates of these tetrapyrroles differed among one another. Acid phosphatase activity was also inhibited with all tetrapyrrole compounds except urobilin. According a Lineweaver-burk plot which showed the inhibition of tetrapyrroles on alkaline and acid phosphatase, biliverdin, urobilin, bilirubin and EDTA inhibited alkaline phosphatase uncompetitively, uncompetitively, competitively and noncompetitively, in that order. Tetrapyrrole compounds noncompetitively inhibited acid phosphatase. On the other hand, gel filtration chromatography of the solution containing alkaline phosphatase and urobilin showed that urobilin took up zinc from the enzyme. These results indicate that the inhibition of tetrapyrrole compounds on phosphatases must be caused by chelate function of tetrapyrrole.View full abstractDownload PDF (379K) -
Tomoji IKEDA, Tatsuro MATSUMOTO, Hiroyuki KISA, Yuzaburo ISHIDA, Akira ...1993 Volume 54 Issue 3 Pages 179-189
Published: July 28, 1993
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSSince the early 1980s freshwater red tides caused by dinoflagellates of the genus Peridinium have frequently occurred mainly on man-made lakes in western Japan. The Kinki district in particular has often experienced red tide blooms of Peridinium bipes f. occultatum. In order to establish the cause of this phenomenon, authors carried out AGP assays by using sample waters taken from three sites, and made an analysis of growth limiting factors of P. bipes in the reservoirs. Clonally isolated and axenic strains of P. bipes were utilized for the AGP assay of waters from the Asahi Reservoir (Nara Prefecture), the Goukawa Reservoir (Wakayama Prefecture) and the Shimokotori Reservoir (Gifu Prefecture) in 1989-90.
The growth of P. bipes was markedly stimulated by the phosphorus which enriched surface water from these reservoirs. Growth was further enhanced when nitrogen was added together with phosphorus. This suggests that phosphorus is the primary growth-limiting factor for P. bipes in these reservoirs.
During 1982-89 the annual mean values in concentrations of total phosphorus and total nitrogen in the Asahi Reservoir had a positive correlation to the daily annual total number of red-tide blooms and with the inflow volume. It is assumed, therefore, that the inflow from the river is the main source of phosphorus supplied to the Asahi Reservoir, and that phosphorus as the primary growth-limiting factor controls the annual frequency in red-tide blooms of P. bipes in this reservoir.View full abstractDownload PDF (619K) -
Shuichi ENDOH, Yasuaki OKUMURA1993 Volume 54 Issue 3 Pages 191-197
Published: July 28, 1993
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSOn the basis of recent current measurements, we propose a new gyre system in Lake Biwa during summer. A great volume of current data was obtained with automatic current meters moored in the surface layer of Lake Biwa during 1977-1991. This data was statistically analyzed to obtain information regarding the time-averaged current velocity field. Trajectories of several drifters tracked by radar were also analyzed to explore typical surface circulation patterns. As a result, the mean surface circulation was found to consist of two large gyres, one counterclockwise and the other clockwise. The positions of these gyres differ substantially from those estimated in previous studies. The so-called Third Gyre was not clearly observed.View full abstractDownload PDF (348K) -
Toshio IWAKUMA, Ryuhei UENO, Seiichi NOHARA1993 Volume 54 Issue 3 Pages 199-212
Published: July 28, 1993
Released on J-STAGE: December 11, 2009
JOURNAL FREE ACCESSFauna and seasonal change of larval populations of Chironomidae were investigated in the eutrophic Lake Yunoko from May 1988 to June 1989. A total of 1, 213 adults belonging to 16 species were obtained by rearing of larvae in sediment collected from 10 stations as well as those in epiphytic matter on submerged plants, mainly Elodea nuttallii (PLANCH)ST. JOHN collected from littoral zones. Diclotendipes lobiger (KIEFFER) and Psectrocladius yunoquartus SASA emerged from sediment samples at≤7 m depth, Tanytarsus nippogregarius SASA et KAMIMURA emerged at≤10 m. Chironomus nipponensis TOKUNAGA, collected from all the stations, was the only species emerging at>10 m depth. C. nipponensis and T. nippogregarius constiuted 93 % of the total adults emerging. From the epiphytic matter on submerged plants, nine species were obtained, of which D. lobiger, P. yunoquartus and Cricotopus trifasciatus (MEICEN), constituted 96 % of the total.
Annual mean density and annual mean biomass of chironomid larvae at 7 m depth were, 2, 210 m-2 and 3.8 g d.w.⋅m-2, respectively, in which C. nipponensis larvae comprised 1800 m-2 (81%) and 3.5 g d.w.⋅m-2 (93%), respectively. Annual mean biomass of Oligochaeta was as high as 13.7 g d.w.⋅m-2.Population of C. nipponensis consisted of two cohorts which overlapped each other. One emerged in April with earlier emergence in the preceding October. The other emerged during late May to July. A large amount of inflowing hot ground water elevated the bottom water temperature, enabling C. nipponensis to reach maturity within a year.
Five out of 15 species recorded in the 1979-1981 survery were not collected in the present study. Changes in submerged plants in both species composition and biomass might have affected chironomid communities.View full abstractDownload PDF (771K) -
Kazuhisa CHIKITA, Yo HOSOGAYA, Shosuke NATSUME1993 Volume 54 Issue 3 Pages 213-224
Published: July 28, 1993
Released on J-STAGE: June 12, 2009
JOURNAL FREE ACCESSThe dynamics of internal waves in a small caldera lake, Lake Kuttara, Hokkaido was examined for the period of September-October 1989, by means of the FFT spectral analysis of time series of water level, water temperature, flow velocity and meteorological conditions. The lake during that period was thermally stratified, but the epilimnion decreased water temperature due to convective cooling. Spectral analysis of water level, water temperature and flow velocity revealed that a lake-current system below the thermocline is characterized by periodic free motions due to rotational internal waves. Meanwhile, a wind system over the lake consisted of daily land-sea breezes and some episodic events due to cyclone lows. The former is characteristic of the lake near the Pacific Ocean. It was oberved that an internal wave rotating counterclockwise or clockwise with periods of 3.1-3.3 hr is induced by both relatively strong sea breezes and episodic eastern-wind events, whereas in the episodic events, an internal wave rotating clockwise with a period of 2.7 hr simultaneously prevails.View full abstractDownload PDF (678K) -
Biological and Chemical CharactereristicsMariyo F. WATANABE, Ken-ichi HARADA1993 Volume 54 Issue 3 Pages 225-243
Published: July 28, 1993
Released on J-STAGE: March 04, 2010
JOURNAL FREE ACCESSThe death of livestock and wildlife owing to the ingestion of dense cells of blue-green algae (cyanobacteria) has been reported in many countries of the world. Biological and chemical characteristics of toxins, mainly those found in Microcystis, were reviewed, since water blooms of Microcystis have occurred in most eutrophic lakes and ponds over a longer period of time than those of any other blue-green algae. The toxins in Microcystis (microcystins) are cyclic heptapeptides composed of two L-amino acids and five common ones with a molecular weight of around 1000. Microcystins RR (the pair of amino acids, arginine-arginine), YR (tyrosine-arginine) and LR (leucine and arginine), were the main components detected in the strains and natural samples of Microcystis in Japan. These three kinds of toxins were contained in the strains of M. viridis and L group of M. aeruginosa. The liver is the main target organ of microcystins. The livers of affected animals were engorged with blood showing hepatocyte necrosis. Neurotoxins were isolated from some species of Anabaena and Aphanizomenon. Anatoxin a in Anabaena is a secondary amine with a molecular weight of 166, and acts as a postsynaptic depolarizing neuromuscular blocking agent. Anatoxin a (s) isolated from An. flos-aquae is N-hydroxyguanidine methyl phosphate ester with a molecular weight of 252 and acts as anti cholinesterase agent. Apha. flos-aquae contains the same saxitoxin and neosaxitoxin as those isolated from the toxic dinoflagellate Alexandrium causing paralytic shellfish poisoning.View full abstractDownload PDF (1403K)
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