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1.
Kunihiro T Miyazaki T Uramoto Y Kinoshita K Inoue A Tamaki S Hama D Tsutsumi H Ohwada K 《Marine pollution bulletin》2008,57(1-5):68-77
We monitored seasonal changes of the abundance and composition of microorganisms in the fish-farm sediment in Kusuura Bay, Amakusa, Japan, using the quinone profiling technique, during bioremediation by introducing cultured colonies of polychaete, Capitella sp. I. In November 2004, approximately 9.2 million cultured worms were transferred to the fish-farm sediment, which increased rapidly, and reached 458.5 gWW/m(2) (528,000 indiv./m(2)) in March 2005. During this fast-increasing period of Capitella, the microbial quinone content of the surface sediment (0-2 cm) also increased markedly, and reached 237 micromol/m(2) in January 2005, although the water temperature decreased to the lowest levels in the year. Particularly, the mole fraction of ubiquinone-10 in total quinones in the sediment, indicating the presence of alpha subclass of Proteobacteria, increased by 9.3%. These facts suggest that the bacterial growth was enhanced markedly by the biological activities of worms in the sediment, and the bacteria played an important role in the decomposition of the organic matter in the sediment. 相似文献
2.
The subsurface current of the Japan Sea was observed by two Autonomous Lagrangian Circulation Explorer (ALACE) floats. One
float, having a 20-day cycle, was deployed on 29 July 1995 in the eastern Japan Basin and drifted in the northeastern part
of the basin until 15 September 2000. The other float, with a 10-day cycle, was deployed on 4 August 1995 in the western Japan
Basin and drifted in the western Japan Basin, in the Yamato Basin and around the Yamato Rise until it reached its life limit
in mid-May 2000. An anticlockwise circulation in the eastern Japan Basin was observed and it was assumed to be in the upper
portion of the Japan Sea Proper Water (UJSPW) or in the intermediate water. The spatial scale of the circulation increased
as the depth decreased. A clockwise circulation was observed around the Yamato Rise in the UJSPW. Smaller clockwise and anticlockwise
rotations were observed in the western Japan Sea, where a seasonal variation was seen in drift speed with different phase
by depth. The correlation coefficient between drift speeds of two floats indicated little coherence among the subsurface circulation
between the east and the west of the Japan Basin, or between the north and the south of the subpolar front.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
Tomoharu?SenjyuEmail author Yutaka?Isoda Takafumi?Aramaki Shigeyoshi?Otosaka Shinzo?Fujio Daigo?Yanagimoto Takashi?Suzuki Kenshi?Kuma Kosuke?Mori 《Journal of Oceanography》2005,61(6):1047-1058
Hydrographic observations have revealed detailed structure of the Bottom Water in the Japan Sea. The Yamato Basin Bottom Water
(YBBW) exhibits higher temperatures and lower dissolved oxygen concentrations than those found in the Japan Basin Bottom Water
(JBBW). Both Bottom Waters meet around the boundary region between the Yamato and the Japan Basins, forming a clear benthic
front. The structure of the benthic front suggests an estuary-like water exchange between both Basins, with the inflow from
the Japan Basin passing under the outflow from the Yamato Basin. It is inferred from the property distributions that the JBBW
flowing into the Yamato Basin is entrained by the cyclonic circulation in the basin, and modified to become the YBBW. Vertical
diffusion and thermal balance in the YBBW are examined using a box model. The results show that the effect of geothermal heating
has about 70% of the magnitude of the vertical thermal diffusion and both terms cancel the advection term of the cold JBBW
from the Japan Basin. The box model also estimates the turnover time and vertical diffusivity for the YBBW as 9.1 years and
3.4 × 10−3 m2s− 1, respectively. 相似文献
4.
Daigo Yanagimoto Masaki Kawabe 《Deep Sea Research Part I: Oceanographic Research Papers》2007,54(12):2067-2081
Direct current measurements with five moorings at 27–35°N, 165°E from 1991 to 1993 and with one mooring at 27°N, 167°E from 1989 to 1991 revealed temporal variations of deep flow at mid-latitude in the western North Pacific. The deep-circulation flow carrying the Lower Circumpolar Deep Water from the Southern Ocean passed 33°N, 165°E northwestward with a high mean velocity of 7.8 cm s−1 near the bottom and was stable enough to continue for 4–6 months between interruptions of 1- or 2-months duration. The deep-circulation flow expanded or shifted intermittently to the mooring at 31°N, 165°E but did not reach 35°N, 165°E although it shifted northward. The deep-circulation flow was not detected at the other four moorings, whereas meso-scale eddy variations were prominent at all the moorings, particularly at 35°N and 29°N, 165°E. The characteristics of current velocity and dissolved oxygen distributions led us to conclude that the deep-circulation flow takes a cyclonic pathway after passing through Wake Island Passage, passing 24°N, 169.5–173°E and 30°N, 168–169°E northward, proceeds northwestward around 33°N, 165°E, and goes westward through the south of the Shatsky Rise. We did not find that the deep-circulation flow proceeded westward along the northern side of the Mid-Pacific Seamounts and eastward between the Hess Rise and the Hawaiian Ridge toward the Northeast Pacific Basin. 相似文献
5.
Deep CTD Casts in the Challenger Deep,Mariana Trench 总被引：1，自引：0，他引：1
Keisuke?TairaEmail author Daigo?Yanagimoto Shoji?Kitagawa 《Journal of Oceanography》2005,61(3):447-454
On 1 December 1992, CTD (conductivity-temperature-depth profiler) casts were made at three stations in a north-south section of the Challenger Deep to examine temperature and salinity profiles. The station in the Challenger Deep was located at 11°22.78′ N and 142°34.95′ E, and the CTD cast was made down to 11197 db or 10877 m, 7 m above the bottom by reeling out titanium cable of 10980 m length. The southern station was located at 11° 14.19′ N and 142°34.79′ E, 16.1 km from the central station, where water depth is 9012 m. CTD was lowered to 7014 db or 6872 m. The northern station was located at 11°31.47′ N and 142° 35.30′ E, 15.9 km from the central station, and CTD was lowered to 8536 db or 8336 m, 10 m above the bottom. Below the thermocline, potential temperature decreased monotonously down to 7300–7500 db beyond a sill depth between 5500 m and 6000 m, or between 5597 db and 6112 db, of the trench. Potential temperature increased from 7500 db to the bottom at a constant rate of 0.9 m°C/1000 db. Salinity increased down to 6020–6320 db, and then stayed almost constant down to around 9000 db. From 9500 db to the bottom, salinity increased up to 34.703 psu at 11197 db. Potential density referred to 8000 db increased monotonously down to about 6200 db, and it was almost constant from 6500 db to 9500 db. Potential density increased from 9500 db in accordance with the salinity increase. Geostrophic flows were calculated from the CTD data at three stations. Below an adopted reference level of 3000 db, the flow was westward in the north of Challenger Deep and eastward in the south, which suggests a cyclonic circulation over the Challenger Deep. Sound speed in Challenger Deep was estimated from the CTD data, and a relation among readout depth of the sonic depth recorder, true depth, and pressure was examined. 相似文献
6.
Abstract. Sandstones with high reservoir quality occur in the Paleogene and Upper Cretaceous coal measures off Sanriku and Sohma in the Pacific coast of northeast Honshu. The sandstone porosity was generally produced by the dissolution of calcite cement and clastic grains such as feldspar and glassy volcanics. The most probable cause of dissolution is the organic acids generated from the maturation of coal and coaly matter in the deeply subsiding source area prior to thermogenic hydrocarbon generation. The pore fluid including organic acids dissolved calcite and clastic silicates to form a small amount of laumontite and kaolinite at around 60C. The acidic and not neutralized pore fluid was responsible for the formation of kaoli-nite. On the other hand, laumontite was formed when the acidic pore fluid was neutralized and then made alkaline after the reaction with minerals such as plagioclase, glassy volcanics and calcite cement. Therefore, laumontite and kaolinite generally occur separately. Laumontite is 0.6–4.6 % by volume, whereas kaolinite is 0.6–9.8 % and the sandstone porosity remains from 10 to 22 %. This type of laumontization after the secondary pore formation might not give a severe damage to the reservoir property of the Paleogene and Upper Cretaceous coal measures in the Pacific coast of northeast Honshu and indicates further exploration possibility. 相似文献
7.
Masaki Kawabe Shinzou Fujio Daigo Yanagimoto Kiyoshi Tanaka 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(10):1675-1687
We conducted full-depth hydrographic observations in the southwestern region of the Northwest Pacific Basin in September 2004 and November 2005. Deep-circulation currents crossed the observation line between the East Mariana Ridge and the Shatsky Rise, carrying Lower Circumpolar Deep Water westward in the lower deep layer (θ<1.2 °C) and Upper Circumpolar Deep Water (UCDW) and North Pacific Deep Water (NPDW) eastward in the upper deep layer (1.3–2.2 °C). In the lower deep layer at depths greater than approximately 3500 m, the eastern branch current of the deep circulation was located south of the Shatsky Rise at 30°24′–30°59′N with volume transport of 3.9 Sv (1 Sv=106 m3 s−1) in 2004 and at 30°06′–31°15′N with 1.6 Sv in 2005. The western branch current of the deep circulation was located north of the Ogasawara Plateau at 26°27′–27°03′N with almost 2.1 Sv in 2004 and at 26°27′–26°45′N with 2.7 Sv in 2005. Integrating past and present results, volume transport southwest of the Shatsky Rise is concluded to be a little less than 4 Sv for the eastern branch current and a little more than 2 Sv for the western branch current. In the upper deep layer at depths of approximately 2000–3500 m, UCDW and NPDW, characterized by high and low dissolved oxygen, respectively, were carried eastward at the observation line by the return flow of the deep circulation composing meridional overturning circulation. UCDW was confined between the East Mariana Ridge and the Ogasawara Plateau (22°03′–25°33′N) in 2004, whereas it extended to 26°45′N north of the Ogasawara Plateau in 2005. NPDW existed over the foot and slope of the Shatsky Rise from 29°48′N in 2004 and 30°06′N in 2005 to at least 32°30′N at the top of the Shatsky Rise. Volume transport of UCDW was estimated to be 4.6 Sv in 2004, whereas that of NPDW was 1.4 Sv in 2004 and 2.6 Sv in 2005, although the values for NPDW may be slightly underestimated, because they do not include the component north of the top of the Shatsky Rise. Volume transport of UCDW and NPDW southwest of the Shatsky Rise is concluded to be approximately 5 and 3 Sv, respectively. The pathways of UCDW and NPDW are new findings and suggest a correction for the past view of the deep circulation in the Pacific Ocean. 相似文献
8.
Kiyoshi Tanaka Kousei Komatsu Sachihiko Itoh Daigo Yanagimoto Miho Ishizu Hiroyasu Hasumi Takashi T. Sakamoto Shogo Urakawa Yutaka Michida 《Journal of Oceanography》2017,73(1):25-38
Hydrographic observations were made in Otsuchi Bay on the Sanriku ria coast, Japan, to provide clear images of the baroclinic circulation extending over the bay together with the associated intrusion of lower-layer water (bottom water) from outside the bay. In summer, a prominent baroclinic circulation with flow speeds \({>} 0.1\ \text{ m }\ \text{ s }^{-1} \) extends over the greater part of the bay. A main pycnocline (thermocline), which separates the upper and lower layers, is located at a depth of 15–40 m in and around the bay. The direction of the lower-layer flow (inflow into and outflow from the bay) is opposite to that of the upper-layer flow, which are baroclinically coupled to each other. Moreover, with regard to the lower-layer flow, the inflow tends to occur mainly through the northwestern part of the bay mouth, whereas the outflow tends to occur mainly through the southeastern part. The inflow and outflow alternate on time scales of several to a few tens of hours, and the flow directions are sometimes related to the tidal ones, although the relationship is not applied persistently. In winter, the baroclinic circulation is considerably weaker than in summer, because the stratification breaks down. 相似文献
9.
A new record of Sebastes koreanus(Kim and Lee,1994) was documented based on morphological characters and DNA barcoding. Fifty-six S ebastes specimens were collected from the coastal waters of northern China. Samples were identified as S. koreanus based on morphological characters. The coloration and morphometric measurements were consistent with those described from specimens collected in South Korea. In this study,specimens had the following morphological characteristics:light brown body with dark stripes and tiny dark spots,4–5 wide indistinct vertical patterns on the side,2 radial stripes behind and below the eyes,1 large dark blotch on the opercle. Additionally,the following meristic characters were recorded:dorsal fin XIV-13,pectoral fin 16,anal fin III-6–7,pelvic fin I-5,lateral line scales 29–30,and vertebrae 26. The fragment of cytochrome oxidase subunit I(C OI) gene of mitochondrial DNA was sequenced for phylogenetic analysis. The mean genetic distance within the species was 0.3%. Net genetic distances between S. koreanus and other S ebastes species ranged from 3.1% to 7.6%,which was greater than the threshold for species delimitation. The phylogenetic analysis strongly supports the validity of S. koreanus in China at the genetic level. The origion,evolution,patterns of speciation and unique features in genome divergence among primate lineages of this species still need future directions of research. 相似文献
10.
Deep and Bottom Currents in the Challenger Deep,Mariana Trench,Measured with Super-Deep Current Meters 总被引：3，自引：0，他引：3
Keisuke?TairaEmail author Shoji?Kitagawa Toru?Yamashiro Daigo?Yanagimoto 《Journal of Oceanography》2004,60(6):919-926
The bottom currents in the Challenger Deep, the deepest in the world, were measured with super-deep current meters moored at 11°22′ N and 142°35′ E, where the depth is 10915 m. Three current meters were set at 9687 m, 10489 m and 10890 m at the station in the center of the Challenger Deep for 442 days from 1 August 1995 to 16 October 1996. Although rotor revolutions in 60 minutes of recording interval were zero for 37.5% of the time, the maximum current at the deepest layer of 10890 m was 8.1 cm s−1, being composed of tidal currents, inertia motion and long period variations. Two current meters were set at 6608 m and 7009 m at a station 24.9 km north of the center for 443 days from 31 July 1995 to 16 October 1996, and two current meters at 6214 m and 6615 m at a station 40.9 km south of the center for 441 days from 2 August 1995 to 16 October 1996. The mean flow at 7009 m depth at the northern station was 0.7 cm s−1 to 240°T, and that at 6615 m depth at the southern station was 0.5 cm s−1 to 267°T. A westward mean flow prevailed at the stations, and no cyclonic circulation with mean flows of the opposite directions was observed in the Mariana Trench at a longitude of 142°35′ E. Power spectra of daily mean currents showed three spectral peaks at periods of 100 days, 28–32 days and 14–15 days. The peak at 100 day period was common to the power spectra. 相似文献