• Ocean and Polar Research
• /
• v.24 no.4
• /
• pp.443-448
• /
• 2002

A study on the ichthyoplankton assemblage was conducted around Dokdo in the East Sea in September 1999 and May 2000. Sixteen species of fish larvae including eggs were collected during the surveys. Anchovy (Engraulis japonicus) eggs and larvae were comprised of 2.0% and 94.5% of total samples in number, respectively. Muller's pearlside (Maurolicus muelleri) eggs and larvae were comprised of 95.0% and 3.2%, respectively. The other species mostly composed of warm water species were less than 2% of total samples in number. The number of species and abundance of the fish lawae and eggs were higher in September than in May. Although there were limited data on the ichthyoplankton around Dokdo in summer and winter, this study area seems to be used for the spawning or nursery ground of fishes.

• Ocean and Polar Research
• /
• v.24 no.1
• /
• pp.87-92
• /
• 2002

The emergy (spelled with an 'm') concept was introduced to provide a new insight into ecosystem restoration efforts in Korea. The emergy is defined as the available energy of one kind previously required directly and indirectly to make a product or service. It is an effort to evaluate the true contributions of natural resources to our economy. It tries to include both contributions from natures free works and human services to develop and process natural resources. The emergy evaluation can be used to select a restoration alternative that yields more to the economy with less stress to the environment, by comparing different alternatives with indices expressed in emergy. It can also be used to assess the success of ecosystem restoration projects. Pulsing dynamics in which a slow build-up of production is followed by a frenzied consumption in relatively short time period seems to be a general feature of all systems. Any ecosystem restoration effort, therefore, should consider the whole pulsing cycle for a successful implementation.

• Ocean and Polar Research
• /
• v.24 no.1
• /
• pp.47-53
• /
• 2002

To evaluate the effect of reed population on the distribution and activities of microorganisms, vertical distribution of heterotrophic bacteria, degradation rate of cellulose, extracellular aminopeptidase activity (APA) and metabolic diversity based on GN2 Microlog plate were measured at two salt marsh stations in Hogok-ri, Namyang Bay, west coast of Korea. The number of heterotrophic bacteria at station 1 (reed population inhabited area) showed 2 to 6 times higher than that of station 2 (exposed area) with exception in the surface layer. Cellulose degradation rates in station 1 showed more than 50%. month-I and higher than that of station 2 (10.2 to 38.4%. $month^{-1}$). Yet the APA at two stations did not show difference except surface layer and suggested that APA might not be a significant factor in degrading marsh plant debris. Lipid class compounds, cell wall polymers and L-alanine were widely used by microorganisms. The number and activities of bacterial populations especially concerned in plant debris degradation seemed to be stimulated by the reed communities.

• Ocean and Polar Research
• /
• v.24 no.4
• /
• pp.359-365
• /
• 2002

The qualitative and quantitative composition of the phytoplankton of the coastal waters off Vladivostok during the period 1991-1994 was studied. The following trends in the phytoplankton composition with decreasing distance from the source of eutrophication were revealed: 1) total density and bio-mass increased; 2) the density of the diatom Skeletonema costatum, which reflects a decrease in the Shannon-Weaver species diversity index during the summer microalgal bloom, increased significantly; and 3) the density of the non-diatom component of the phytoplankton increased.

• Ocean and Polar Research
• /
• v.26 no.4
• /
• pp.647-653
• /
• 2004

Experimental studies with 4.3m and enlarged 30m in height have been conducted to investigate the flow characteristics of solid-liquid mixture in a lifting pipe and to acquire the design data for sea tests that will be performed in the future. From the results, it was observed that the more the discharged volume fraction and the solid diameter increase, the more the hydraulic gradient increases. Also, the more the diameter of the lifting pipe increases, the smaller the friction loss, and consequently, the less pressure drop and hydraulic gradient. From the enlarged hydraulic pumping experiments, it was shown that the results of the experiments were matched with those of the numerical model previously developed. On the bases of these studies, we plan to conduct further experiments and validate the hydraulic pumping model.

• Ocean and Polar Research
• /
• v.26 no.4
• /
• pp.655-668
• /
• 2004

A taxonomic survey of the dinoflagellate family Dinophysiaceae Stein was conducted on 17 locations off the coast of Korea. A total of twelve species have been identified and described, of which eight species, Dinophysis dens Pavillart D. infundibulus Schiller, D. irregulare Lebour, D. lapidistrigiliformis Abe, D. mitra(Schutt) Abe vel Balech, D. parvula(Schutt) Jorgensen, D. rapa(Stein) Balech, Phalacroma sphaeroideum Schiller, are new records for Korea and six are potentially toxic.

• Ocean and Polar Research
• /
• v.25 no.2
• /
• pp.155-182
• /
• 2003

An annotated listing of bivalve mollusks collected at 31 sampling sites in Yeongil Bay (eastern coast of Korea) at a depth of 0-52m is presented here. A total of 98 species belonging to 75 genera and 36 families are enumerated; all species are provided with habitat data (bathymetric distribution and bottom sediments character), given separately far living and dead (empty shells) specimens, and some with taxonomic and zoogeographic comments. Fifty-six species are illustrated with photographs. Astarte hakodatensis Yokoyama, 1920 (Astartidae), Nitidotellina pallidula (Lischke 1871) (Tellinidae) and Lyonsia nuculanoformis Scarlato in Volova et Scarlato, 1980 (Lyonsiidae) are found to be new to the Korean fauna, and the genus Salaputium Iredale, 1924 (Crassatellidae) with one species Salapurium Iredale, 1924(Crassatellidae) with one species Salaputium cf. unicum Hayami and Kase, 1993, previously described as being found only from submarine caves in the Ryukyu Islands, is recorded as being found in the East Sea(Sea of Japan) for the first time.

• Ocean and Polar Research
• /
• v.33 no.3
• /
• pp.223-233
• /
• 2011

The Korean government has acknowledged the importance of Dokdo Island and has consequently taken various measures for the effective management of it. There has, however, been little quantitative information about the value of Dokdo Island and this study, therefore, attempts to assess the Islands non-market value. To this end, this study estimated the non-market value by MAUT/CVM. The non-market value estimated by MAUT/CVM includes historic value, military value, ecological value, and geological value. According to the results, the values calculated by the price in market is about 10.37 trillion won and the values estimated by MAUT/CVM is about 1.72 trillion won annually.

• Ocean and Polar Research
• /
• v.36 no.1
• /
• pp.71-76
• /
• 2014

This study aims to analyze the market interactions among the main farmed fish species in Korea, using both multivariate and bivariate cointegration analysis. For the analysis of market interactions among farmed fish species, major four farmed fish species, olive flounder (Paralichthys olivaceus), black rockfish (Sebastes schlegeli), red seabream (Pagrus major), and grey mullet (Mugil cephalus) were selected as the analytical target species. And their real price data by month from January 2000 to December 2011 were used in the analysis. The results of the multivariate cointegration test for four farmed fish showed that there would be no long-term equilibrium relationships among farmed fish species, and consequently they do not share the same market. The results of bivariate cointegration test indicated that there was little evidence to suggest that all farmed fish species were cointegrated each other. However, it was only analyzed that olive flounder and grey mullet might have a long run equilibrium relationship.

• Ocean and Polar Research
• /
• v.35 no.1
• /
• pp.63-68
• /
• 2013

The European Common Barnacle Balanus perforatus Brugiere (Crustacea, Cirripedia) has been introduced into the east coast of Korea, presumably via the ballast water of ships. The species has since been spreading along both the northern and southern coast to the east, most likely due to alongshore currents. We predicted the potential range expansion of Balanus perforatus in Korean waters using Genetic Algorithm for Rule-set Prediction (GARP), an environmental niche modeling technique. The results show that much of the southern coastal waters of Korea could be colonized by the spread of the nonindigenous species, but that the west coast is unlikely to be invaded. More sampling on the west coast would enhance the predictability of the model. To our knowledge, this is the first report of its kind for predicting marine nonindigenous species in Korean waters using GARP modeling.