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31.
Chang?-Woong?ShinEmail author Cheolsoo?Kim Sang?-Kyung?Byun Dongchull?Jeon Sang?-Chull?Hwang 《Ocean Science Journal》2006,41(4):291-299
Hydrographic surveys were carried out four times in the western channel of the Korea Strait in March and August 2003 and in
June and November 2004. The bottom cold water, which was lower than 10°C, appeared in the channel trough except in March 2003.
It flowed southwestward along the shelf of Korean coasts in August 2003 and in November 2004. The width and the maximum speed
of the intrusion current were about 20 km and approximately 25 cm s-1, respectively, off Ulsan, Korea. The volume transport of the bottom cold water was estimated 0.019 Sv (Sv≡106 m3 s-1) in August 2003 and 0.026 Sv in November 2004. 相似文献
32.
Morphogenesis of a population of the marine euplotid ciliate, Uronychia binucleata, which was found in Yellow Sea coastal waters next to a sewage outfall at a beach near Zhanqiao Pier, Qingdao, China, was investigated using protargol staining. The main pattern of morphogenesis is typical for the genus and can be summarized as follows: 1) the oral primordium in both proter and opisthe develops de novo in a subcortical pouch. In each daughter cell, the developing adoral zone of membranelles divides into two parts. The new membranelles formed in the proter's oral primordium will replace the leftmost five parental ones; six parental membranelles are retained by the proter; 2) the undulating membranes anlage is formed and develops independently from the oral primordium within the same subcortical pouch; 3) five primary front oventral-transverse cirral anlagen appear de novo on the cell surface; 4) the marginal cirral anlagen are formed de novo; 5) the leftmost frontal cirrus develops de novo on the cell surface; 6) two caudal cirri are formed at the posterior end of the rightmost anlage while the second primordium from the right gives rise to the third caudal cirrus. In contrast to its congeners, the anlage of the leftmost frontal cirrus is formed to the right of the undulating membranes anlage and before the formation of the latter. 相似文献
33.
Bhavya P. S. Min Jun-Oh Kim Min-Seob Jang Hyo Keun Kim Kwanwoo Kang Jae Joong Lee Jae Hyung Lee Dabin Jo Naeun Kim Myung Joon Kim Yejin Lee Junbeom Lee Chang Hwa Bae Hyeonji Yoo Hyeju Park Sanghoon Yun Mi Sun Lee Sang Heon 《Ocean Science Journal》2019,54(4):515-528
Ocean Science Journal - Investigations on marine N2 fixation have gained momentum since 1960s with eventual establishments of relevant methodologies to identify species involved and quantify the... 相似文献
34.
Sumi Kanij Rukshana Kim Soo Cheol Howlader Jewel Sharker Md Rajib Choi Kap Seong Choi Sang Ki Park Jong-In Nou Ill-Sup Kho Kang Hee 《Ocean Science Journal》2019,54(3):363-374
Ocean Science Journal - A carbonic anhydrase VII gene, encoding 277 amino acids, was identified in the intestinal tissue of pufferfish (Takifugu rubripes). The translated protein with an 833-bp... 相似文献
35.
Many regions around the world require improved gravimetric data bases to support very accurate geoid modeling for the modernization
of height systems using GPS. We present a simple yet effective method to assess gravity data requirements, particularly the
necessary resolution, for a desired precision in geoid computation. The approach is based on simulating high-resolution gravimetry
using a topography-correlated model that is adjusted to be consistent with an existing network of gravity data. Analysis of
these adjusted, simulated data through Stokes’s integral indicates where existing gravity data must be supplemented by new
surveys in order to achieve an acceptable level of omission error in the geoid undulation. The simulated model can equally
be used to analyze commission error, as well as model error and data inconsistencies to a limited extent. The proposed method
is applied to South Korea and shows clearly where existing gravity data are too scarce for precise geoid computation. 相似文献
36.
Bathymetry enhancement by altimetry-derived gravity anomalies in the East Sea (Sea of Japan) 总被引:1,自引:0,他引:1
Kwang Bae Kim Yu-Shen Hsiao Jeong Woo Kim Bang Yong Lee Yi Kyun Kwon Chang Hwan Kim 《Marine Geophysical Researches》2010,31(4):285-298
The gravity-geologic method (GGM) was used to enhance the bathymetry of the East Sea (Sea of Japan) with satellite altimetry-derived
free-air gravity anomalies and shipborne depth measurements. By comparison with the bathymetry model of Smith and Sandwell’s
(SAS) approach (1994), GGM was found to have an advantage with short wavelength (≤12 km) components, while SAS better predicts
longer wavelength (≥25 km) components, despite its dependency on density contrast. To mitigate this limitation, a tuning density
contrast of 10.25 g/cm3 between seawater and the seafloor was primarily estimated by the downward continuation method and then validated by the check
points method with GGM. Similarly, SAS is limited by the “A” value in low-pass part of the Wiener filter, which defines the effective range of the wavelength components on bathymetry.
As a final result, we present an enhanced GGM bathymetry model by integrating all available data. 相似文献
37.
Kiseong Hyeong Inah Seo Hyun-Bok Lee Chan Min Yoo Sang-Bum Chi In Kwon Um 《Ocean Science Journal》2018,53(2):355-368
Radionuclide activities of 210Pb and 226Ra were measured to determine bioturbation coefficients (Db) in seven sediment cores from the Korean licensed block for polymetallic nodules in the Clarion–Clipperton Fracture Zone. Variability in Db is considered in the context of the sedimentological, geochemical, and geotechnical properties of the sediments. Db values in the studied cores were estimated using a steady-state diffusion model and varied over a wide range from 1.1 to 293 cm2/yr with corresponding mixing depths (L) of 26 to 144 cm. When excepting for spurious results obtained from cores where diffusive mixing does not apply, Db values range from 1.1 to 9.0 cm2/yr with corresponding mixing depths (L) of 26 to 63 cm. Such wide variability in Db and L values is exceptional in sites with water depths of ~5000 m and is attributed in this study to an uneven distribution of sediment layers with different shear strengths and total organic carbon (TOC) contents, caused by erosion events. The studied cores can be grouped into two categories based on lithologic associations: layers with high maximum shear strength (MSS) and low TOC content, showing a narrow range of Db values (1.1–9.0 cm2/yr); and layers with low MSS and high TOC content, yielding much higher Db values of over 30 cm2/yr. The distribution of different lithologies, and the resultant spatial variability in MSS and labile organic matter content, controls the presence and maximum burrowing depth of infauna by affecting their mobility and the availability of food. This study provides a unique case showing that shear strength, which relates to the degree of sediment consolidation, might be an important factor in controlling rates of bioturbation and sediment mixing depths. 相似文献
38.
Hyun Suk Park Choong-Gon Kim Sung Kim Yong-Joo Park Hee-Jung Choi Zhizhong Xiao Jun Li Yongshuang Xiao Youn-Ho Lee 《Ocean Science Journal》2018,53(2):261-274
The rock bream, Oplegnathus fasciatus, is a common rocky reef game fish in East Asia and recently has become an aquaculture species. Despite its commercial importance, the population genetic structure of this fish species remains poorly understood. In this study, 163 specimens were collected from 6 localities along the coastal waters of Korea and China and their genetic variation was analyzed with mtDNA COI sequences. A total of 34 polymorphic sites were detected which determined 30 haplotypes. The genetic pattern reveals a low level of nucleotide diversity (0.04 ± 0.003) but a high level of haplotype diversity (0.83 ± 0.02). The 30 haplotypes are divided into two major genealogical clades: one that consists of only Zhoushan (ZS, East China Sea) specific haplotypes from the southern East China Sea and the other that consists of the remaining haplotypes from the northern East China Sea, Yellow Sea, Korea Strait, and East Sea/Sea of Japan. The two clades are separated by approximately 330~435 kyBP. Analyses of AMOVA and Fst show a significant population differentiation between the ZS sample and the other ones, corroborating separation of the two genealogical clades. Larval dispersal and the fresh Yangtze River plume are invoked as the main determining factors for this population genetic structure of O. fasciatus. Neutrality tests and mismatch distribution analyses indicate late Pleistocene population expansion along the coastal waters of Korea and China approximately 133–183 kyBP during which there were periodic cycles of glaciations and deglaciations. Such population information needs to be taken into account when stock enhancement and conservation measures are implemented for this fisheries species. 相似文献
39.
The relationship between significant wave height and period, the variability of significant wave period, the spectral peak enhancement factor, and the directional spreading parameter of large deepwater waves around the Korean Peninsula have been investigated using various sources of wave measurement and hindcasting data. For very large waves comparable to design waves, it is recommended to use the average value of the empirical formulas proposed by Shore Protection Manual in 1977 and by Goda in 2003 for the relationship between significant wave height and period. The standard deviation of significant wave periods non-dimensionalized with respect to the mean value for a certain significant wave height varies between 0.04 and 0.21 with a typical value of 0.1 depending upon different regions and different ranges of significant wave heights. The probability density function of the peak enhancement factor is expressed as a lognormal distribution, with its mean value of 2.14, which is somewhat smaller than the value in the North Sea. For relatively large waves, the probability density function of the directional spreading parameter at peak frequency is also expressed as a lognormal distribution. 相似文献
40.
In this article, by using the daily precipitation data measured at 58 meteorological stations, spatial and temporal variability of daily precipitation including zero rainfall values (called “precipitation”) and without zero rainfall values (called “rain”) and four precipitation extrema (P0, P20, P50, and P100 representing the daily precipitation with the magnitude smaller than 0.1 mm, bigger than 20 mm, 50 mm, and 100 mm per day, respectively) in the Yangtze River Delta (YRD) during 1958–2007 were analyzed, and the effects of urbanization were further investigated. Results indicate that (i) differing from the downward trends in 1958–1985, daily precipitation and rain in 1986–2007 show slowly downward trends in the mid YRD but show upward trends in the northern and southern YRD. (ii) Spatial and temporal variability of the rain is more complex than daily precipitation. Both of them become smaller but show more obvious fluctuations in 1986–2007. (iii) Urbanizations cause not only the urban rainfall island problem but also more obvious fluctuations of rain intensity in the mid YRD, reflecting more uncertainty of daily precipitation variability. (iv) Urbanizations have little effects on the variability of P0 and P100 but cause notable increases of P20 and P50. (v) The spatial variability of daily precipitation and precipitation extrema in 1958–1985 clearly shows a breakpoint at 30°20′N latitude, but the breakpoint disappears afterward because of the effects of urbanization. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献