Marine Environment Research Division

Mungyeong, South Korea

Marine Environment Research Division

Mungyeong, South Korea
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Lee J.S.,Oceanographic Measurement and Instrument Calibration Service Center | Kim E.-S.,Oceanographic Measurement and Instrument Calibration Service Center | Kahng S.-H.,Oceanographic Measurement and Instrument Calibration Service Center | Yoon S.-H.,Marine Environment Research Division | And 3 more authors.
Ocean Science Journal | Year: 2012

We have developed a novel miniature in situ microprofiler (NAFRI BelpI) for coastal and deep-sea studies. The BelpI can carry up to three oxygen microsensors, and it allows for simultaneous replicate measurements in a relatively small area. All functions can be controlled and programmed via a small magnetic bar and three reed switches; this feature facilitates the initial setup both onboard and underwater. The large LCD window shows basic information such as the movement intervals of the linear stage, number of replicate measurements, waiting time between measurements, and the pA from the microsensors. From high-resolution vertical profiles of oxygen in coastal sediment measured using the microsensors, the diffusivity boundary layer thicknesses was determined to be in the range 0. 30-0. 35 mm. In addition, the time-series measurement of oxygen profiles in permeable sandy sediment showed advective transport of oxygen into pore water by tidal agitation. Two examples of in situ measurement using a BelpI suggest that it can be widely applied to the study of the sediment-water interface. © 2012 Korea Ocean Research & Development Institute (KORDI) and the Korean Society of Oceanography (KSO) and Springer Science+Business Media Dordrecht.


Choi S.-H.,Data Management | Kim D.,Maritime and Ocean Engineering Research Institute | Shim J.H.,Marine Environment Research Division | Min H.S.,Maritime and Ocean Engineering Research Institute
Ocean Science Journal | Year: 2011

Fugacity of CO 2 (fCO 2), temperature, salinity, nutrients, and chlorophyll-a were measured in the surface waters of southwestern East Sea/Japan Sea in July 2005. Surface waters were divided into three waters based on hydrographic characteristics: the water with moderate sea surface temperature (SST) and high sea surface salinity (SSS) located east of the front (East water); the water with high SST and moderate SSS located west of the front (West water); and the water with low SST and SSS located in the middle part of the study area (Middle water). High fCO 2 larger than 420 μatm were found in the West water. In the Middle water, CO 2 was undersaturated with respect to the atmosphere, with values between 246 and 380 μatm. Moderate fCO 2 values ranging from 370 to 420 μatm were observed in the East water. For the East and West waters, estimates of temperature dependency of fCO 2 (12. 6 and 15. 1 μatm°C -1, respectively) were rather similar to a theoretical value, indicating that SST is likely to be a major factor controlling the surface fCO 2 distribution in these two regions. In the Middle water, however, the estimated temperature dependence was somewhat lower than the theoretical value, and relatively high concentrations of surface chlorophyll-a coincided with the low surface fCO 2, implying that biological uptake may considerably affect the fCO 2 distribution. The net sea-to-air CO 2 flux of the study area was estimated to be 0. 30±4. 81 mmol m -2 day -1 in summer, 2005. © 2011 Korea Ocean Research Development Institute (KORDI) and the Korean Society of Oceanography (KSO) and Springer Netherlands.


Choi M.,Marine Environment Research Division | Furlong E.T.,U.S. Geological Survey | Werner S.L.,U.S. Geological Survey | Pait A.S.,East-West Center | And 2 more authors.
Ocean Science Journal | Year: 2014

Concerns have emerged regarding the presence of human-use pharmaceuticals in aquatic environments. We investigated the status of contamination by 29 human-use pharmaceuticals as well as wastewater indicator compounds, fecal sterols and the synthetic endocrine disruptor nonylphenol, in marine sediments from Masan Bay, one of the most contaminated bays in Korea as a result of untreated and/or treated sewage. Among the 29 pharmaceuticals determined, 10 including antacid, analgesic, antibiotic, and antipruritic compounds, and metabolites of caffeine and nicotine were detected in all sediment samples. Cimetidine, acetaminophen, and 1,7-dimethylxanthine were the most frequently detected pharmaceuticals (frequency > 50%), and at high concentrations. The highest concentrations and detection frequencies were at stations located close to wastewater treatment plant (WWTP) outfalls and at the river mouth. The spatial distributions of pharmaceutical were significantly correlated with those of wastewater compounds. These results indicate that occurrence of the pharmaceuticals in marine environments is likely associated with direct sewage inputs, such as WWTP effluents and with other sewage-influenced sources, such as river discharge. © KSO, KIOST and Springer 2014.


Lee J.S.,Marine Environment Research Division | Kim Y.-T.,Marine Environment Research Division | Shin K.-H.,Hanyang University | Hyun J.-H.,Hanyang University | Kim S.-Y.,Marine Environment Research Division
Aquaculture International | Year: 2011

To assess the impact of aquaculture activities, we measured the primary production, total sediment oxygen consumption, and benthic nutrient flux at two aquaculture farms (sea squirt and oyster) and one reference site. The estimated primary production in the water column ranged from 19-169 mmol C m-2 d-1. Total sediment oxygen consumption rates ranged from 58 to 328 mmol m-2 d-1, 1. 1 to 40 mmol m-2 d-1 for nitrogen, 0. 17 to 3. 0 mmol m-2 d-1 for phosphate, and 7. 3 to 74 mmol m-2 d-1 for silicate. The average total sediment oxygen consumption at the longline farms was > 2. 5 times higher than the reference site. Nitrate was significantly removed by denitrification at the longline farms in July and September and ranged from -5. 4 to -0. 09 mmol m-2 d-1, which is higher than for other coastal sediments. The benthic fluxes of nitrogen and phosphate at longline farms were up to 16 and six times higher than at the reference site, respectively. The average nitrogen requirements of the primary producers were 9. 3 mmol m-2 d-1 at the sea squirt farm, 7. 0 mmol m-2 d-1 at the oyster farm, and 13. 5 mmol m-2 d-1 at the reference site, corresponding to 88, 316, and 27. 2% of the nitrogen supplied by benthic fluxes, respectively. Our results suggest that benthic nutrient fluxes at longline farms are a major nutrient source for primary production in coastal waters. © 2011 Springer Science+Business Media B.V.


Kim K.-S.,Pukyong National University | Shim J.H.,Marine Environment Research Division | Kim S.,Pukyong National University
Ocean Science Journal | Year: 2015

It widely thought that ocean acidification processes that caused by atmospheric CO2 increase and accordingly lower seawater pH conditions might cause serious harm to marine food webs in certain ecosystems in the near future. Little is known about how marine fishes respond to reduced pH conditions. We investigated the effects of CO2 conditions on the growth of olive flounder (Paralichthys olivaceus) larvae. Newly hatched larvae were reared at three different levels of pCO2 (574, 988 and 1297 µatm) in temperature-controlled (21 ± 0.5°C) water tanks for four weeks until metamorphosis. The experiment was repeated three times in May, June, and July 2011, and body lengths and weights were measured at the completion of each experiment. The results indicated that the body length and weight of flounder larvae significantly increased with increasing CO2 concentrations (P < 0.05). A higher daily growth rate during the early larval stage (hatching to 14 days) was found among the larvae reared in low pCO2 conditions, while a significantly lower growth rate was found among larvae in higher pCO2 water conditions. On the other hand, in the late larval stage (18 days after hatching to metamorphosis), the daily growth rate of larvae was much higher in high CO2 water. Bone density of larvae, however, decreased with increasing CO2 concentration in the water © 2015, Korea Ocean Research & Development Institute (KORDI) and the Korean Society of Oceanography (KSO) and Springer Science+Business Media Dordrecht.


Lee S.H.,Pusan National University | Joo H.T.,Pusan National University | Lee J.H.,Pusan National University | Kang J.J.,Pusan National University | And 3 more authors.
Ocean Science Journal | Year: 2015

A short (4–5 hour) incubation method for a 13C-15N dual isotope tracer technique has been widely applied for the measurements of daily primary and new productions of phytoplankton. However, there has been no research conducted to determine if there are any differences in the estimated daily productions between short incubation periods and 24 hour incubations. Based on hourly uptake rates estimated from a 4 hour incubation at a coastal site in the East/Japan Sea, the daily carbon and nitrogen uptake rates of total phytoplankton were approximately 60% overestimated compared to those derived from a 24 hour incubation. Especially for large phytoplankton, the daily carbon uptake rates based on the 4 hour incubation were greatly overestimated (> 200%). In contrast, the daily rates of small phytoplankton were not significantly different between the two different incubations. This is mainly because the daily carbon and nitrogen uptake rates of large phytoplankton were significantly correlated with light intensity. Consequently, the contributions of small phytoplankton were underestimated whereas large phytoplankton contributions were overestimated in daily carbon and nitrogen uptake rates based on a 4 hour incubation. Further investigations into these potential overestimations in daily carbon and nitrogen uptake rates of phytoplankton, especially for large size cells, will be needed to be carried out in order to obtain better estimations of annual primary and new productions. © 2015, Korea Ocean Research & Development Institute (KORDI) and the Korean Society of Oceanography (KSO) and Springer Science+Business Media Dordrecht.


Park J.-I.,Marine Eco Technology Institute | Son M.H.,Marine Eco Technology Institute | Kim J.B.,Marine Environment Research Division | Lee K.-S.,Pusan National University
Ocean Science Journal | Year: 2014

Phyllospadix japonicus is an abundant surfgrass that thrives mainly along the exposed rocky shores of Northeastern Asia. On the eastern coast of Korea, surfgrass populations have been adversely affected by increasing human pressures. We developed a seeding method using an artificial reef for the restoration of P. japonicus. In January 2005, we planted P. japonicus seeds on the lower part of coarse hemp-plant brush that was embedded densely on the concave surface on the top of artificial reefs. The reefs were then installed on an exposed rocky shore. To evaluate the feasibility of this seed-based surfgrass restoration technique, we monitored the seedling/shoot density and morphological characteristics of the shoots over a 2-year period. Seedlings began to emerge within the first month after seeding, reaching densities of up to 275.0 shoots m-2 by April 2005. After an initial decline, shoot density increased through the production of lateral shoots, and densities of up to 997.1 shoots m-2 were observed by the end of the experiment. Shoot height, the number of leaves, and leaf width rapidly increased during the first year after seeding, whereas the number of rhizome internodes and rhizome length rapidly increased during the second year. The P. japonicus shoots exhibited approximately 63.4 mm of rhizome elongation during the study period. Because seeded P. japonicus on the artificial reefs were successfully established at the study site, this seeding method using an artificial reef may offer an effective approach to restoring surfgrass habitat. © 2014, Korea Ocean Research & Development Institute (KORDI) and the Korean Society of Oceanography (KSO) and Springer Science+Business Media Dordrecht.


Park J.-I.,Marine Eco Technology Institute | Kim J.B.,Marine Environment Research Division | Lee K.-S.,Pusan National University | Son M.H.,Marine Eco Technology Institute
Ocean Science Journal | Year: 2013

To select the optimal site for the restoration of seagrass habitats in the Taehwa River estuary, we transplanted the eelgrass Zostera marina to three potential candidate sites in March 2007 and monitored the transplanted seagrass and associated environmental factors for six months. In all three sites, the transplanted seagrasses exhibited no initial morphological loss due to transplanting stress. The transplanted seagrass communities at sites 2 and 3 showed more than a 180% increase in density over the entire survey period. In contrast, despite a density increase in the first month after transplantation, most of the transplanted seagrasses at site 1 died. This may be due to the large decrease in underwater irradiance reaching the seagrass leaves at site 1 for two months during June and July, which fell below the level of compensation irradiance. The growth rate and size of the seagrass shoots were also larger at sites 2 and 3 compared with site 1. This is probably due to higher nutrient concentrations in the sediment pore water at sites 2 and 3 compared with site 1, although water depth, salinity, and the nutrient concentrations in the water columns from the three sites were similar. Therefore, for the restoration of seagrass habitats in the Taehwa River estuary, sites 2 and 3 were preferable to site 1 as transplantation sites. © 2013 Korea Ocean Research & Development Institute (KORDI) and the Korean Society of Oceanography (KSO) and Springer Science+Business Media Dordrecht.


Kim J.B.,Marine Environment Research Division | Lee W.-C.,Marine Environment Research Division | Lee K.-S.,Pusan National University | Park J.-I.,Marine Eco Technology Institute
Ocean Science Journal | Year: 2013

To examine the growth dynamics of eelgrass, Zostera marina, in the intertidal zone of Seomjin Estuary, Korea, we surveyed environmental factors such as water temperature, underwater irradiance, tidal exposure, and nutrient concentrations in the water column and sediment pore water in relation to the shoot density, biomass, morphological characteristics, and growth of Z. marina inhabiting the upper and lower intertidal zones. The survey was conducted monthly from January 2003 to December 2004. The water temperature of the two areas displayed seasonal fluctuations. Underwater irradiance was significantly higher in the upper intertidal zone than in the lower intertidal zone. Tidal exposure was also markedly longer in the upper intertidal zone than in the lower intertidal zone, whereas tidal exposure was highest in the spring and lowest in the summer in both areas. Water column NH4 + and sediment pore water NO3 -+NO2 - concentrations were significantly higher in the upper intertidal zone than the lower intertidal zone. The eelgrass shoot density, biomass, morphology, and leaf productivity were significantly higher in the lower intertidal zone than in the upper intertidal zone. Both areas displayed a clear seasonal variation depending on changes in water temperature. However, leaf turnover time was significantly shorter in the upper intertidal zone than in the lower intertidal zone, with a higher turnover rate in the upper intertidal zone. Compared to the seagrasses in the lower intertidal zone, those in the upper intertidal zone showed more effective adaptations to the stress of long tidal exposure through downsizing and increased turnover time. These results suggest that tidal exposure, coupled with desiccation stress, can be a limiting factor for seagrass growth in the intertidal zone, along with underwater irradiance, water temperature, and nutrient availability. © 2013 Korea Ocean Research & Development Institute (KORDI) and the Korean Society of Oceanography (KSO) and Springer Science+Business Media Dordrecht.


Kim S.-G.,Climate and Marine Environment Team | Kim S.-S.,Climate and Marine Environment Team | Choi H.-G.,Marine Environment Research Division | An Y.-R.,Cetacean Research Institute
Ocean Science Journal | Year: 2011

Concentrations of trace metals (As, Cd, Cr, Cu, Pb, Hg, Se, and Zn) were determined in the livers, kidneys, muscles, intestines, and hearts of twelve long-beaked common dolphins (Delphinus capensis) from the East Sea, Korea, in 2006. All specimens were entangled in various commercial fishing nets or traps and as such are recorded as by-catch. The concentrations of Cu, Hg, Se, and Zn were much higher in the liver than in the kidney, muscle, intestine, or heart. Trace metals that accumulated in the liver were, in descending order: Zn > Hg > Cd > Se > Cu > As > Cr > Pb. In contrast, the concentration of Cd was higher in the kidney than in any other organs. The trace metals accumulated in the kidney were, in descending order: Cd > Zn > Cu > Hg > Se > As > Pb > Cr. No significant differences were found in the concentrations of As, Cr, or Pb in all the tissues examined. © 2011 Korea Ocean Research & Development Institute (KORDI) and the Korean Society of Oceanography (KSO) and Springer Netherlands.

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