First Investigation of Microbial Community Composition in the Bridge (Gadeok Channel) between the Jinhae-Masan Bay and the South Sea of Korea     

Jiyoung Lee  Jae-Hyun Lim  Junhyung Park  Seok-Hyun Youn  Hyun-Ju Oh  Ju-Hyoung Kim  Myung Kyum Kim  Hyeyoun Cho  Joo-Eun Yoon  Soyeon Kim  Kesavan Markkandan  Ki-Tae Park  Il-Nam Kim 《Ocean Science Journal》2018,53(2):251-260

Microbial community composition varies based on seasonal dynamics (summer: strongly stratified water column; autumn: weakly stratified water column; winter: vertically homogeneous water column) and vertical distributions (surface, middle, and bottom depths) in the Gadeok Channel, which is the primary passage to exchange waters and materials between the Jinhae-Masan Bay and the South Sea waters. The microbial community composition was analyzed from June to December 2016 using 16S rRNA gene sequencing. The community was dominated by the phyla Proteobacteria (45%), Bacteroidetes (18%), Cyanobacteria (15%), Verrucomicrobia (6%), and Actinobacteria (6%). Alphaproteobacteria (29%) was the most abundant microbial class, followed by Flavobacteria (15%) and Gammaproteobacteria (15%) in all samples. The composition of the microbial communities was found to vary vertically and seasonally. The orders Flavobacteriales and Stramenopiles showed opposing seasonal patterns; Flavobacteriales was more abundant in August and December while Stramenopiles showed high abundance in June and October at all depths. The genus Synechococcus reached extremely high abundance (14%) in the June surface water column, but was much less abundant in December water columns. Clustering analysis showed that there was a difference in the microbial community composition pattern between the strongly stratified season and well-mixed season. These results indicate that the seasonal dynamics of physicochemical and hydrologic conditions throughout the water column are important parameters in shaping the microbial community composition in the Gadeok Channel.  相似文献   

Effects of Temperature and Salinity on the Egg Development and Larval Settlement of Ciona robusta (Ascidiacea,Phlebobranchia, Cionidae)     

Kim  Min Kyung  Kim  Dong Hyun  Park  Ju-un  Kim  Dong Hwan  Yoon  Tae Joong  Kim  Dong Gun  Lee  Yoon  Shin  Sook 《Ocean Science Journal》2019,54(1):97-106

Ocean Science Journal - Ascidians are marine benthic organisms, which attach to the surfaces of both natural and artificial substrates from shallow to deep waters around the world. Invasive...  相似文献   

Physiological Responses of Cultured Seaweed Pyropia yezoensis to Phosphorous Limitation in the Nakdong River Estuary,Korea     

Kim  Sangil  Yoon  Sang Chol  Yoo  Man Ho  Park  Kyung Woo  Park  Sang Rul  Youn  Seok-Hyun 《Ocean Science Journal》2019,54(1):129-139

Ocean Science Journal - Pyropia yezoensis cultured in the estuary of the Nakdong River in Korea is an important fisheries resource for the local economy. Over the past few decades, the...  相似文献   

A Numerical Modeling of the Upper and the Intermediate Layer Circulation in the East Sea   总被引：1，自引：0，他引：1  

Cheol-Ho Kim  Jong-Hwan Yoon 《Journal of Oceanography》1999,55(2):327-345

Circulation in the upper and the intermediate layer of the East Sea is investigated by using a fine resolution, ocean general circulation model. Proper separation of the East Korean Warm Current from the coast is achieved by adopting the isopycnal mixing, and using the observed heat flux (Hirose et al., 1996) and the realistic wind stress (Na et al., 1992). The simulated surface circulation exhibits a remarkable seasonal variation in the flow patterns of the Nearshore Branch, the East Korean Warm Current and the Cold Currents. East of the Oki Bank, the Nearshore Branch follows the isobath of shelf topography from late winter to spring, while in summer and autumn it meanders offshore. The Nearshore Branch is accompanied by cyclonic and anticyclonic eddies in a fully developed meandering phase. The meandering and the eddy formation of the Nearshore Branch control the interior circulation in the Tsushima Current area. A recirculation gyre is developed in the region of the East Korean Warm Current in spring and grown up to an Ulleung Basin scale in summer. A subsurface water is mixed with the fresh surface water by winter convection in the northeastern coastal region of Korea. The well-mixed low salinity water is transported to the south by the Cold Currents, forming the salinity minimum layer (Intermediate Water) beneath the East Korean Warm Current water. The recirculation gyre redistributes the core water of the salinity minimum layer in the Ulleung Basin. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Five <Emphasis Type="Italic">Oncaea</Emphasis> species (Copepoda,Poecilostomatoida, Oncaeidae) from the Korean waters,with notes on the spatio-temporal distribution of Korean oncaeid species     

Jin Hee Wi  Yang Ho Yoon  Ho Young Soh 《Ocean Science Journal》2009,44(2):95-115

Five Oncaea species were recorded on the basis of specimens collected using three type nets from the South Sea and the East Sea of Korea. These included the clevei-group of one species (O. clevei) and the venusta-group of four species (O. media, O. mediterranea, O. scottodicarloi, O. waldemari). The former has a dorsoposterior projection on the second pedigerous somite, while the latter do not bear any dorsal projection on the somite. Also, their spatio-temporal distribution are discussed in relation to temperature-salinity.  相似文献   

Simulation of the nonlinear dynamic interactions between waves, a submerged breakwater and the seabed     

Dong-Soo Hur  Chang-Hoon Kim  Do-Sam Kim  Jong-Sung Yoon   《Ocean Engineering》2008,35(5-6):511-522

This study employed direct numerical simulation to simulate the fully nonlinear interaction between the water waves, the submerged breakwater, and the seabed under differing wave conditions. In the numerical simulation, the laminar flow condition in the seabed was applied to evaluate the more exact fluid resistance acting on the porous media. Varying incident wave conditions were applied to the flow field resulting from the wave–structure–seabed interaction, and the variation in the pore water pressure beneath the submerged breakwater was investigated along the cross-section of the submerged breakwater. Structural safety and scouring were also considered on the basis of the numerical results for the flow field around the structure and the variation of the pore water pressure.  相似文献   

Description of feeding apparatus and mechanism innemopilema nomurai kishinouye (scyphozoa: rhizostomeae)     

Hye Eun Lee  Won Duk Yoon  Donghyun Lim 《Ocean Science Journal》2008,43(1):61-65

Feeding apparatus, mechanism and passage of ingested prey were described forNemopilema nomurai (Scyphozoa: Rhizostomeae).N. nomurai medusae without central mouths have developed complicated canal systems connecting the tip of the tentacle and oral arm to the gut cavity. The number of junctions in the canal system increases with the bell diameter. The prey is gathered by paralyzing nematocyst at the tentacles and by adhering cirri at the oral arms and scapulets. They are engulfed into the terminal pore located at the oral arms and scapulets, and entered into the gut cavity via the canal system. The estimated digestion time is 1 hour and 20 min. The diameter of terminal pore is always about 1 mm, implying that they could not eat prey larger than that pore size. On the other hand, ephyrae have central mouths and could swallow prey as large as adults could. Exploitation of the same size of food by adult and ephyra implies thatN. nomurai can affect seriously the whole food web, massively ingesting micro-and mesozoopl a n k t o n and cutting the energy transfer toward the higher level of carnivores.  相似文献   

Lithium as a Silicate Weathering Proxy: Problems and Perspectives     

Junyeon Yoon 《Aquatic Geochemistry》2010,16(1):189-206

The lithium concentration of the dissolved load from the Lena River, together with major element chemistry and GIS-based area and runoff data demonstrate the importance of evaporites in controlling dissolved Li in river waters. Eighty-four percent of the Li in the dissolved load of upper Lena tributaries comes from evaporites in these drainage basins. Altogether, at least ~20% of the total Li flux of the Lena River originates from this source. This finding has important implications for using lithium as a proxy for silicate weathering. The Li flux and the ⁸⁷Sr/⁸⁶Sr ratio are compared in order to address a difference between the two silicate weathering rate proxies. The proposed controls on the dissolved δ⁷Li values in rivers (kinetic vs. equilibrium isotopic fractionation; Rayleigh-type preferential extraction of the heavy isotope) (Huh et al., Earth Planet Sci Lett 194:189–199, 2001) are evaluated using data from both the Siberian rivers and the Orinoco River. Neither of the proposed mechanisms satisfactorily explains the comprehensive data set. Instead, a ‘mineralogy-specific view’ that emphasizes the difference in the secondary mineralogy (i.e., fractionation factor) is presented as a potential rationalization in the form of the refined Rayleigh-type extraction.  相似文献   

The CLIVAR C20C project: selected twentieth century climate events   总被引：3，自引：1，他引：2  

A. A. Scaife  F. Kucharski  C. K. Folland  J. Kinter  S. Brönnimann  D. Fereday  A. M. Fischer  S. Grainger  E. K. Jin  I. S. Kang  J. R. Knight  S. Kusunoki  N. C. Lau  M. J. Nath  T. Nakaegawa  P. Pegion  S. Schubert  P. Sporyshev  J. Syktus  J. H. Yoon  N. Zeng  T. Zhou 《Climate Dynamics》2009,33(5):603-614

We use a simple methodology to test whether a set of atmospheric climate models with prescribed radiative forcings and ocean surface conditions can reproduce twentieth century climate variability. Globally, rapid land surface warming since the 1970s is reproduced by some models but others warm too slowly. In the tropics, air-sea coupling allows models to reproduce the Southern Oscillation but its strength varies between models. We find a strong relationship between the Southern Oscillation in global temperature and the rate of global warming, which could in principle be used to identify models with realistic climate sensitivity. This relationship and a weak response to ENSO suggests weak sensitivity to changes in sea surface temperature in some of the models used here. In the tropics, most models reproduce part of the observed Sahel drought. In the extratropics, models do not reproduce the observed increase in the North Atlantic Oscillation in response to forcings, through internal variability, or as a combination of both.  相似文献   

Aerosol properties at gosan in Korea during two pollution episodes caused by contrasting weather conditions   总被引：1，自引：0，他引：1  

Jin Young Kim  Sang-Woo Kim  Young Sung Ghim  Chul Han Song  Soon-Chang Yoon 《Asia-Pacific Journal of Atmospheric Sciences》2012,48(1):25-33

We analyzed aerosol optical and chemical properties over Northeast Asia for two pollution episodes caused by contrasting weather conditions, stagnant anticyclone (November, 2011) and fastmoving continental outflow associated with migratory cyclone/anticyclone (February, 2003). Pollution levels were significantly high and even comparable with heavily polluted urban cities in China and Korea even though these levels were from the episodic measurements since Gosan is an internationally well-known remote background site. Space-borne MODIS measurements clearly show that the pollution plume with high aerosol optical depth (AOD) overlaid and very slowly moved over Northeast Asia during the stagnation episode. On the other hand, a strong synoptic wind transported the plume from eastern China to its downwind regions during the continental outflow episode. The two pollution episodes showed discriminative aerosol chemical compositions associated with different source characteristics. Concentrations of nss (non-sea-salt)-sulfates and ammonium in the continental outflow episode were almost two times higher than those in the stagnation episode due to the influence of anthropogenic emissions from China. A higher fraction of nitrate, accompanied with an increase of carbonaceous species in the stagnation episode, was attributable to vehicular emissions originated from Korea.  相似文献