An experimental transplantation to select the optimal site for restoration of the eelgrass Zostera marina in the Taehwa River estuary     

Jung-Im Park  Jeong Bae Kim  Kun-Seop Lee  Min Ho Son 《Ocean Science Journal》2013,48(4):311-318

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Copepods of Hatschekiidae (Copepoda, Siphonostomatoida) new to Korean fauna, with description of a new species     

Seong Yong Moon  Il-Hoi Kim 《Ocean Science Journal》2013,48(1):19-34

Eight species of the Hatschekiidae are recorded as parasites of marine fishes from southern coast of Korea. One new species, Hatschekia jejuensis, parasitic on Cheilodactylus zonatus Cuvier is included. The remaining seven species are new to Korean fauna: Hatschekia iridescens Wilson, 1913, H. japonica Jones, 1985, H. monacanthi Yamaguti, 1939, H. tenuis (Heller, 1865) H. pseudolabri Yamaguti, 1953, H. cylindrica Shiino, 1957, and Pseudocongericola chefoonensis Yü, 1933. Hatschekia jejuensis n. sp. has a combination of characteristics in the female where the trunk is 2.35 times as long as the cephalothorax and displays a pair of posterolateral bulges on both sides, the antennules is 5-segmented, the mandible bears six teeth, and the armature formulae of the legs are I-0; III (exopod) and 0-0; II (endopod) for leg 1 and I-0; I (exopod) and 0-0; II (endopod) for leg 2.  相似文献   

Morphology and molecular characterization of the epiphytic dinoflagellate Prorocentrum cf. rhathymum in temperate waters off Jeju Island, Korea     

An Suk Lim  Hae Jin Jeong  Tae Young Jang  Nam Seon Kang  Sung Yeon Lee  Yeong Du Yoo  Hyung Seop Kim 《Ocean Science Journal》2013,48(1):1-17

Prorocentrum spp. are planktonic and/or benthic species. Benthic Prorocentrum species are of primary concern to scientists and the public because some of them are toxic. We established clonal cultures of 3 strains of Prorocentrum species that were collected from the thalli of a macroalga in the coastal waters off Jeju Island, located at the southern end of Korea. The Korean strains of P. cf. rhathymum, which are morphologically almost identical to the Virgin Island strain of P. rhathymum, were different from P. mexicanum because the former dinoflagellate has one simple collar-like spine in the periflagellar area, while the latter dinoflagellate has a 2- or 3-horned spine. In addition, the sequences of the small subunit (SSU) rDNA of the Korean strains were identical to those of the Malaysian and Floridian strains of P. rhathymum, while the sequences of the large subunit (LSU) rDNA of the Korean strains were 0.1–0.9% different from those of the Iranian and Malaysian strains of P. rhathymum. In phylogenetic trees based on the SSU rDNA sequences, the Korean strains of P. rhathymum formed a clade with the Malaysian and Floridian strains of P. rhathymum and the Vietnamese and Polynesian strains of P. mexicanum. However, in phylogenetic trees based on the LSU rDNA sequences, the Korean strains of P. rhathymum formed a clade with the Iranian strain of P. rhathymum and the Spanish and Mexican strains of P. mexicanum. Therefore, the molecular characterization of the Korean strains does not allow us to clearly classify them as P. rhathymum, nor P. mexicanum, although their morphology has so far been reported to be closer to that of P. rhathymum than P. mexicanum and thus we designated them as P. cf. rhathymum.  相似文献   

Derivation and assessment of a bivariate IDF relationship using paired rainfall intensity–duration data     

Kee-Won Seong  Yong-Hak Lee 《Stochastic Environmental Research and Risk Assessment (SERRA)》2009,23(1):1-7

A procedure is presented for developing a rainfall intensity–duration–frequency (IDF) relationship that is consistent with bivariate normal distribution modeling. The Box–Cox transformation was used to derive the relation and two methods of determining the parameters of this transformation were evaluated. To assess the uncertainty of the parameters, a confidence interval was constructed and verified with the non-parametric bootstrap method. Additionally, the effect of sample size on the bivariate normality assumption was examined. Case studies, based on data from significant gauge stations in Korea, were performed. The result shows that the use of the bivariate normal model as an IDF relationship is particularly recommended when the available data size is small.  相似文献   

Gap size effect on the tribological characteristics of the roller for deep-sea mining robot     

Jae-Won Oh  Hyung-Woo Kim  Sup Hong  Ki-Young Sung  Dae-Sung Bae 《Marine Georesources & Geotechnology》2017,35(1):120-126

To design the deep-sea mining robot, it is essential to analyze the tribological characteristics of its roller. In this study, we introduced the dynamic simulation model to analyze the tribological characteristics of the roller for deep-sea mining robot, considering the temperature, viscosity, viscous damping force, and gap size between the inner and outer rib seals. Effective viscosity changes with gap size in micro/nanoscale while the effective viscosity is equal to the kinematic viscosity in macroscale. For the stable operation of the roller, the effective viscosity must be less than the critical viscosity. As the gap size decreases, the effective viscosity increases while the critical viscosity decreases. This study shows that the gap size between the inner and outer rib seals of roller is the most dominant factor in designing the roller for deep-sea mining robot to use at relatively low temperatures that are found in the deep-sea environments.  相似文献   

Growth and reproduction of the Japanese mantis shrimp, <Emphasis Type="Italic">Oratosquilla oratoria</Emphasis> (De Haan 1844) in the coastal area of Tongyeong,Korea     

SeongEun Kim  HanJu Kim  HoJin Bae  Hyeong-Gi Kim  Chul-Woong Oh 《Ocean Science Journal》2017,52(2):257-265

Growth and reproduction of the Japanese mantis shrimp, Oratosquilla oratoria, were investigated in the Tongyeong, Korea from July 2014 to August 2015. A total of 2,621 samples (1,380 females and 1,241 males) were collected during the study period. Females were observed more frequently than males. The mean body length (BL) was 128.5 ± 0.38 mm in females and 126.9 ± 0.42 mm in males. The mean body weight (BW) was 31.2 ± 0.28 g in females and 31.1 ± 0.32 g in males. There was a significant difference in the length-frequency distribution between females and males. The relationship between BL and BW was lnBW = 2.85 × lnBL - 10.43 for females and lnBW = 2.87 × lnBL -10.52 for males. The gonadosomatic index (GSI) varied on a monthly basis. The GSI reached a maximum in May and a minimum in November. The highest values of the GSI coincided with the spawning period of O. oratoria. Larger individuals of O. oratoria have their spawning season earlier than smaller ones. The size at sexual maturity of females was estimated as 96.5 mm. The Von Bertalanffy growth function parameters were BL_∞ = 184.5 mm, K = 0.72 year^?1, C = 0.36 and WP = 0.45 for females and BL_∞ = 183.75 mm, K = 0.82 year^?1, C = 0.38 and WP = 0.22 for males. The growth of males was slightly faster than females. The present study will help with the fisheries management of O. oratoria based on ecological parameters.  相似文献   

Occurrence of gorgosterol in diatoms of the genus Delphineis     

Sebastiaan W. Rampen  John K. Volkman  Sung Bum Hur  Ben A. Abbas  Stefan Schouten  Ian D. Jameson  Daniel G. Holdsworth  Jean Hee Bae  Jaap S. Sinninghe Damsté 《Organic Geochemistry》2009,40(1):144-147

The presence of the C₃₀ sterol gorgosterol (22,23-methylene-23,24-dimethylcholest-5-en-3ß-ol) and its analogues in some marine and freshwater environments is generally associated with invertebrate animals or dinoflagellates since there have been no reports of them in other microalgal classes. Here we show that two unialgal cultures of different species of the marine diatom Delphineis contain gorgosterol in addition to sterols more commonly found in diatoms. Our findings suggest that some reports of gorgosterol in seawater and marine sediments may well have an origin, at least in part, from diatoms.  相似文献   

Integrated watershed management for mitigating streamflow depletion in an urbanized watershed in Korea   总被引：3，自引：0，他引：3  

Kil Seong Lee  Young-Oh Kim 《Physics and Chemistry of the Earth》2008,33(5):382-394

A systematic, seven-step approach to integrated watershed planning and management is applied to an urbanized watershed, the Anyangcheon (AY) watershed in Korea which consists of (1) understanding watershed components and processes, (2) identifying and ranking problems to be solved, (3) setting clear and specific goals, (4) developing a list of management options, (5) eliminating infeasible options (6) testing the effectiveness of remaining feasible options, and (7) developing the final options. Watershed characteristics, water quantity and quality simulations with SWAT and PLOAD models, and the developed problem indices of PFD (Potential Flood Damage), PSD (Potential Streamflow Depletion), and PWQD (Potential Water Quality Deterioration) identify that streamflow depletion is more serious than flood risk and water pollution in the study watershed (Steps 1 and 2). Instreamflow requirements, which are the maximum value of the average low flow and the fish flow, are estimated using regional regression and the software PHABSIM (Step 3). Feasible solutions that improve the depleted streams are listed and screened qualitatively against technical, economical, and environmental criteria (Steps 4 and 5). Effectiveness of the remaining 14 feasible alternatives are then analyzed using SWAT (Step 6) and alternative evaluation index (AEI) and their priority ranks are determined against an evaluation criterion that uses the concept of pressure, state, and response (Step 7).  相似文献   

Seasonal and spatial characteristics of seawater and sediment at Youngil Bay, southeast coast of Korea   总被引：1，自引：0，他引：1  

Lee M  Bae W  Chung J  Jung HS  Shim H 《Marine pollution bulletin》2008,57(6-12):325-334

The seasonal geochemical characteristics of the seawater and sediments and the major factors causing heavy metal contamination were investigated at the Youngil bay and the Hyungsan river estuary in the Southeast Coast of Korea, where a world-scale steel-industry complex (Pohang iron and steel industrial complex, POSCO) is located. The seasonal and spatial distribution characteristics of temperature, dissolved oxygen (DO), pH, and nutrients of the seawater were studied at 45 fixed stations, especially focusing on the river mouth area. Sediments at 27 stations were examined during winter and summer to determine the major controlling factors for the distribution of metals, using correlation matrix and R-mode factor analyses, and to evaluate the pollution status, using the modified geoaccumulation (I(geo)(')) index. Temperatures for the effluent from the POSCO located at the Hyungsan river mouth were 2-3 degrees C higher compared to other sampling areas, due to the thermal discharge from the POSCO. The DO concentration of the surface water at the Pohang old port was as low as 2-4 mg/L. In spring, the DO value at the Hyungsan river mouth was higher than 12 mg/L, by the mass multiplication of phytoplanktons at the river mouth where seawater temperature and nutrients concentrations were relatively high, resulting in the pH value of higher than 8.3. The nitrogen to phosphorus (N/P) ratios at the river mouth were 20-150 times higher compared to other areas, implying that the nitrogen loading into this semi-enclosed bay is significantly higher than phosphorus and the major nitrogen sources are not only the domestic sewage from the city but the industrial wastewater from the POSCO and other steel factories nearby. The phosphorus concentrations at the Pohang old port were shown 3-10 times higher than those at other stations, due to the inflow of pollutants generated from the nearby ships anchoring and the release of phosphate from the bottom sediment. Results from the sediment analysis showed that the major controlling factors for the distribution pattern of each metal are grain size and organic carbon (C(org)) content. Based on the factor analysis, Al, Fe, Cr, Li, and Pb were shown strongly correlated with the mean grain size (Mz), whereas Cd, Cu, Zn, and Sn with the C(org) content. Results from the fractionation of the sedimentary metals into lattice and labile fractions to characterize the mobility of sediment metals showed that the mineral lattice fraction was high in the order of Al=K>Cr>Li>Sr>Fe, while the labile fraction, which might be released to the overlying water, was in the order of Pb>Zn>Cd>Cu>Ca>Sn. Evaluation of the sediment pollution status by applying (I(geo)(')) of 13 metals showed Cd, Cu, and Zn as high as 1-3 range at the old port. Even though the overall marine pollution mainly by the world-class steel industrial complex in this semi-enclosed bay area studied does not currently pose a serious threat, due to the seawater circulation and the large influx of river discharge, the countermeasures to implement the sediments concentrated with heavy metals, especially at the old port with no seawater circulation, are still warranted for this coastal water environment.  相似文献   

Degradation of crude oil in a contaminated tidal flat area and the resilience of bacterial community     

Jaejin Lee  Il Han  Bo Ram Kang  Seong Heon Kim  Woo Jun Sul  Tae Kwon Lee 《Marine pollution bulletin》2017,114(1):296-301

Crude oil spills, Hebei Spirit in South Korea, is considered as one of the worst environmental disasters of the region. Our understanding on activation of oil-degrading bacteria and resilience of microbial community in oil contaminated sites are limited due to scarcity of such event. In the present study, tidal flat sediment contaminated by the oil spill were investigated for duration of 13 months to identify temporal change in microbial community and functional genes responsible for PAH-degradation. The results showed predominance of previously known oil-degrading genera, such as Cycloclasticus, Alcanivorax, and Thalassolituus, displaying significant increase within first four months of the accident. The disturbance caused by the oil spill altered the microbial community and its functional structures, but they were almost restored to the original state after 13 months. Present study demonstrated high detoxification capacity of indigenous bacterial populations in the tidal flat sediments and its resilience of microbial community.  相似文献