Growth characteristics ofChattonella antiqua     

Yasuo Nakamura  Makoto M. Watanabe 《Journal of Oceanography》1983,39(4):151-155

Nutrient requirements of a red tide flagellate,Chattonella antiqua, were investigated in a laboratory culture experiment. Growth ofC. antiqua was supported by nitrate and ammonium, and by urea to a limited extent, but not by glycine, alanine and glutamate. Orthophosphate served as a good phosphorus source but glycerophosphate did not. Fe³⁺ (1µM) fully promoted the flagellate's growth in the presence of 80µM of EDTA. The addition of Mn²⁺ (0–20µM), Zn²⁺ (0–10µM) and Co²⁺ (0–0.4µM) did not show any effect. Among three vitamins tested, only B₁₂ (6 ng 1^?1) served as a growth factor. Glucose, acetate and glycolate did not improve growth in the light nor did they support growth in darkness. The minimum cell quotas for nitrogen, phosphorus, iron and B₁₂ were estimated to be 11 pmoles ce^?1, 1.0, ～0.09 and 1.1 fg cell^?1, respectively.  相似文献   

Warm water intrusion from the Kuroshio into the coastal areas south of Japan   总被引：1，自引：0，他引：1  

Akihide Kasai  Shingo Kimura  Takashige Sugimoto 《Journal of Oceanography》1993,49(6):607-624

Sea surface temperature (SST) has been measured in the south of Japan using a thermometer set up in the ferry boat to investigate the characteristics of the warm water intrudes into the coastal areas from the Kuroshio. Time series analysis was applied to the SST data with satellite images and hydrographic observation data from April 1987 to September 1989. The results indicate that the warm Kuroshio water intruded into the coastal areas on the Enshu-nada and the Kumano-nada Seas intermittently with periods of about 50 and 20 days associated with the fluctuation of the Kuroshio path and the Kuroshio frontal disturbance respectively. The intrusion with a 50-day period was dominant when the Kuroshio took a stationary small meander path (B- and C-types). The warm water spread to the west at 20 cm s^–1, and was estimated to have a depth of 150 m at least and supply enough heat to make up the loss due to the evaporation in the coastal area. During the straight path of the Kuroshio, it was detected that the warm water intruded into coastal areas only with a 20-day period. The warm water that intrudes with a period of 20 days spreads to the west at 25 cm s^–1 in a small scale.  相似文献   

Two records of patchy occurrences of the oceanic shrimpSergestes similis Hansen off the east coast of Honshu,Japan     

Mitsumori Mutoh  Makoto Omori 《Journal of Oceanography》1978,34(1):36-38

Two recent records of the occurrences of the pelagic shrimp,Sergestes similis Hansen, are reported. They provide evidence of dense swarms ofS. similis in midwater off the east coast of Honshu, Japan, in spring. On one occasion,S. similis was found in a stomach of the basking shark,Cetorhinus maximus (Gunnerus). The shark, 8.11 m in total length, was accidentally trapped in a set net off Izu-oshima Island on April 18, 1974, and its foregut was filled only withS. similis. Feeding and swimming behavior of the basking shark, condition of the gut contents, and temperature profiles of the sea revealed thatS. similis was preyed upon by the shark near the island when the shrimp swarmed below 100 m depth at night. On another occasion,S. similis was fished by a commercial ground trawler 31 miles off Cape Shioyazaki on April 4 and 5 and off Hitachi on April 11, 1976. The trawlings were made around 500 m depth at daytime, and a total of 3.8 tons ofS. similis was caught and marketed. The size-frequency distribution and sex ratio ofS. similis in both occurrences from off Izu-oshima Island and off Cape Shioyazaki coincided very well. The samples consisted of identical population of probably 2nd year class having a body length mode between 46.0 and 50.0 mm. The sex ratio was skewed greatly toward females in both samples, that is 38∶2 and 100∶3 respectively. These two phenomena are discussed in relation to the life history ofS. similis.  相似文献   

A pump-sampler as a method of collecting plankton and its preliminary operation     

Akihiko Kuwahara  Tsuneyuki Abe  Masayuki Shimono  Makoto Kashiwai  Masatosi Sinoda 《Journal of Oceanography》1973,29(3):106-112

A pump-sampler was designed to study the distribution of marine plankton and its possible relationship with the temperature and salinity of the water. Sea water was pumped up through a 2 inch diameter hose and plankton contained in it was collected on a filter cup (2 inches in diameter, 139 meshes/inch) without being damaged. The filter cup, when clogged by plankton organisms, was washed by spraying with about 100 cu. cm of water. The differences between two continuous with an interval of more than 3–4 seconds could be detected.A preliminary operation along a 2.82 km course in Maizuru Bay was carried out simultaneously with temperature-salinity measurements at sampling intervals of 30 m. Temperature was measured by a thermistor resistance thermometer, and salinity was measured by a salinometer with a subsample of water which was collected from an additional opening of the pump-sampler. The temperature-salinity record showed that four zones of water were characterized.It was found that wide variation of plankton counts indicated dense concentrations of particular species or group of species, and on the mesoscale it was possible to examine the size of the aggregation.  相似文献   

An Ecological-Physical Coupled Model with Ontogenetic Vertical Migration of Zooplankton in the Northwestern Pacific     

Michio J. Kishi  Hitoshi Motono  Makoto Kashiwai  Atsushi Tsuda 《Journal of Oceanography》2001,57(5):499-507

A vertical one-dimensional ecosystem model with vertical migration of zooplankton was constructed and applied to Station A-7 off Sanriku district of Japan in the northwest Pacific Ocean. The model consists of an eight-compartment ecosystem model coupled with a physical model of the oceanic mixed layer. The transition of phytoplankton species responsible for the spring bloom is well reproduced by this model with vertical migration of zooplankton but is not simulated by the model without vertical migration. This new model also simulates an observed inter-annual variability of the spring bloom, with the timing and intensity of the simulated bloom in a given year depending upon the strength of mixing during the preceding winter. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Study of metal contents of elasmobranch fishes: part 1—metal concentration in the muscle tissues of a dogfish, squalus mitsukurii     

Masashi Taguchi  Kenji Yasuda  Shozo Toda  Makoto Shimizu 《Marine environmental research》1979,2(3):239-249

Concentrations of Hg, Zn, Fe, Cd and Cu in the muscle tissues of a dogfish, Squalus mitsukurii, were determined by atomic absorption spectrometry and found to be in the ranges of f0·019–2·13, 1·8–3·6, 1·5–5·7, 0·001–0·018 and 0·12–0·70 μg/g wet weight, respectively. The frequency distributions of concentrations, with the exception of mercury, were found to be log-normal. The correlation coefficient between mercury content and total length was positive and large and statistically highly significant. For other metals negative correlations were observed. Mercury concentration in the muscle was found to increase in proportion to the total length cubed. Regression of mercury concentration on age of sharks was shown to be linear. Analysis of covariance showed that the difference between sexes was not statistically significant, either in slope or in height. The concentration of mercury in the muscle tissues of embryos was considerably lower, Cd roughly the same and Zn and Fe higher than those of mothers. The concentrations of Zn, Fe and Cu are higher in the embryonic stage and immediately after birth than in later stages of growth.  相似文献   

Age validation of walleye pollock (Theragra chalcogramma) from the Gulf of Alaska using the disequilibrium of Pb-210 and Ra-226     

Kastelle  Craig R.; Kimura  Daniel K. 《ICES Journal of Marine Science》2006,63(8):1520-1529

  相似文献   

Effect of dietary docosahexaenoic acid on lipogenesis and lipolysis in black sea bream, Acanthopagrus schlegeli   总被引：2，自引：0，他引：2  

JI Hong  OM Ahamd Dau  YOSHIMATSU Takao  UMINO Testuy  NAKAGAWA Heisuke  FURUHASHI Makoto  SAKAMOTO Shuichi 《海洋学报(英文版)》2007,26(1):112-121

1 IntroductionIt is well known that varying dietary fatty acidprofile affects the tissue fatty acid composition and e-ven the growth performance in fish ( Bell et al.,2002; Figueiredo -Silva et al., 2005; Harel andPlace, 2003; Schulz et al., 2005; Tocher et al.,2003). Docosahexaenoic acid (DHA), an importantessential fatty acid for marine species, has the effectnot only on the fatty acid profile of fish body tissue,but also on biological and physiological conditions(Ishizaki et al., 2000; …  相似文献   

Fortnightly shifts of intrusion depth of oceanic water into Ise Bay     

Akihide?KasaiEmail author  Tateki?Fujiwara  Takuma?Kimura  Hirokatsu?Yamada 《Journal of Oceanography》2004,60(5):817-824

To clarify the time change in water exchanges between Ise Bay and the adjacent ocean, repeated hydrographic observations were conducted along the longitudinal section in Ise Bay. The results show that the mixing condition at the bay mouth (Irago Strait) changed fortnightly in summer. During the spring tides, the strait water below the pycnocline was well-mixed and nearly homogeneous. By contrast, it was weakly stratified during the neap tide. There is a strong negative correlation between the tidal range and the density difference between the upper and lower layers at the strait. In summer, the intrusion depth of oceanic water into the bay and consequent hydrographic conditions inside the bay changed frequently according to the tidal strength. During the spring tides a prominent bottom front was created at the bay mouth, indicating that the strait water, which is a mixture of oceanic and bay waters, intruded through the middle layer. On the other hand, during the neaps, cold and saline oceanic water intruded through the bottom layer into the bay. The intrusion depth is significantly correlated with the tidal range. It is considered that the wellmixed strait water, which has a density equivalent to the middle layer inside the bay, is lighter than the bottom bay water and thus intrudes through the middle layer during the spring tides, while insufficient mixing makes the bottom water at the strait heavier than the bay water, leading to the bottom intrusion during the neap tides.  相似文献   

Observation of Sea Surface Temperature by an Infrared Radiation Thermometer     

Ryuji Kimura  Nobuhiko Misawa 《Journal of Oceanography》1970,26(1):22-37

Laboratory experiments were made to examine some characteristics of a radiation thermometer (PRT 14–313, Barnes Engineering Company). Effect of nonblackness of the water surface and a large temperature difference between the water and the air above it were investigated. Sea surface temperatures were then measured by the radiation thermometer, thermistor thermometers and a mercury thermometer from a marine tower. The result showed that the temperature at the air-sea interface was not always cooler than the subsurface temperature. The standard deviation of difference of temperatures measured by the radiation thermometer and the thermistor thermometer was 0.44°C. The dependence of the temperature difference on various factors was investigated with the result that current velocity had a good correlation with the temperature difference.  相似文献