• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.2
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• pp.174-190
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• 1996

Damage assessment based on in situ surveys for oil spills in marine environment is limited by fundamental difficulties as well as tremendous expenses. Except for intertidal zones, the damage is not preserved well. Also such surveys are usually confined to adult organisms. To overcome these limitations a computer model, NRDAM/CME, was developed in the case of USA (Reed et al., 1989), where an acute toxicity data base was used to assess indirect damages through food webs and loss due to recruitment as well as adult losses. In the present study damage assessment of natural biological resources for hypothetical oil spills is attempted using a computer model for hypothetical spills of Bunker C and heavy crude oil. In the model, the logical structure of NRDAM/CME was adopted, and biomass and productivity database were compiled for the Korean waters. The results showed that the damage increased in a nonlinear fashion as the spill amount increased. The magnitude of the damage depended upon the chemical properties of oil viscosity and solubility in particular, which implies that usage of oil dispersant might increase the damage by dispersing oil. The results also indicate that long term damage due to recruitment loss could be greater than short term damage.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.2
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• pp.157-164
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• 2009

The metals such as Al, Ag, Au, Cu, Cd, Co, Fe, Ni, Pb, Zn, etc are present at very low concentration in seawater and are classified as so-called trace metals. Whiles some of them are used in metabolism of living organism as a micronutrient, they may show toxic effects on organisms in case of a limited threshold concentration of them Plenty of studies on trace metals have been performed bemuse trace metals have a persistent influence and an adverse effect on marine environment and ecosystem. For long years, when the concentration of trace metals in natural waters such as seawater and fresh water are measured with high precision and accuracy, some systematic errors have been recognized to be present in measurements. Since 1975 in US and European countries, the measured concentration of trace metals in seawater have been found to be lower by factors of 10-1,000 than the previous data of trace metals measurements and the vertical profiles of the measurements have been shown to reflect well-known biological, physical and geochemical processes. These results are attributed to great advances in analytical instrumentation and methodology for trace metals measurements. Precautions against the contamination of samples are required to be taken in the process of sampling, storage, and analysis of samples. However, in Korea, erroneous data of trace metals with regard to ocean and marine environment related survey and investigations are reported The lock of exact understanding and information regarding precautions in sampling, storage and analysis of samples lead to the deterioration of data quality, especially in the analysis of trace metals. The major procedures to obtain the accurate data of trace metals in natural waters are introduced for applying to the study and assessment of marine environments.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.455-462
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• 2000

The objective of this study was to examine the physicochemical characteristics of coagulation reaction between loess and red tide organisms (RTO) and its feasibility, in developing a technology for the removal of RTO bloom in coastal sea. The physicochemical characteristics of loess were examined for a particle size distribution, surface characteristics by scanning electron microscope, zeta potential, and alkalinity and pH variations in sea water. Two kinds of RTO that were used in this study, Cylindrothen closterium and Skeietonema costatum, were sampled in Masan bay and were cultured in laboratory. Coagulation experiments were conducted using various concentrations of loess, RTO, and a jar tester. The supernatant and RTO culture solution were analyzed for pH, alkalinity, RTO cell number. A negative zeta potential of loess increased with increasing pH at $10^(-3)M$ NaCl solution and had -71.3 mV at pH 9.36. Loess had a positive zeta potential of +1,8 mV at pH 1.98, which resulted in a characteristic of material having an amphoteric surface charge. In NaCl and $CaCl_2$, solutions, loess had a decreasing negative zeta potential with increasing $Na^+\;and\;Ca^(+2)$ ion concentration and then didn't result in a charge reversal due to not occurring specific adsorption for $Na^+$ ion while resulted in a charge reversal due to occurring specific adsorption for $Ca^(+2)$ ion. In sea water, loess and RTO showed the similar zeta potential values of -112,1 and -9.2 mV, respectively and sea sand powder showed the highest zeta potential value of -25.7 mV in the clays. EDLs (electrical double-layers) of loess and RTO were extremely compressed due to high concentration of salts included in sea water, As a result, there didn't almost exist EDL repulsive force between loess and RTO approaching each other and then LVDW (London-yan der Waals) attractive force was always larger than EDL repulsive force to easily form a floe. Removal rates of RTO exponentially increased with increasing a loess concentration. The removal rates steeply increased until $800 mg/l$ of loess, and reached $100{\%}$ at 6,400 mg/l of loess. Removal rates of RTO exponentially increased with increasing a G-value. This indicated that mixing (i.e., collision among particles) was very important for a coagulation reaction. Loess showed the highest RTO removal rates in the clays.

• Korean Journal of Ichthyology
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• v.32 no.2
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• pp.103-109
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• 2020

The diet composition of whitespotted conger, Conger myriaster was studied using 129 specimens collected in the coastal waters Geoje, Korea from June 2018 to May 2019. The size of the specimens ranged from 11.5~22.9 cm in preanus length (AL). C. myriaster was a piscivore that consumes mainly pisces such as Engraulis japonicus and Gobiidae (%IRI: 98.4%). Of the fish species E. japonicus was the most preferred prey. Based on these results, it is considered that Conger myriaster has a characteristic of feeding on abundant prey organisms in the study area. The dietary compositions of C. myriaster was not significantly different among size classes. These results are considered to be due to a lack of specimens and the various size groups were not collected. Based on these results, it is thought that immature fishes inhabit the coast of Geoje. As body size of C. myriaster increased the mean weigh of prey per stomach (mW/ST) tended to increase (one-way ANOVA, P<0.05).

• The Korean Journal of Quaternary Research
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• v.18 no.2 s.23
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• pp.65-66
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• 2004

There have been groves, in many cases, along with hedgerows and remnant forests around a traditional Korean village. A village grove is very closely connected to the life of residents. Sometimes it was a holy place where important village festivals were held, and became a resting place for farmers, especially in sunny summer. As a matter of fact, it is noted that traditional Korean village groves had been fostered for many purpose as religion, Confucianism, scenery, sanitation, traffic guard, public security, agriculture, hunting, and military and public uses were included in Chosun Govemor General(1938). Village groves were usually located at the outlet of watershed inside which a village was built. In addition, village groves used to be established along part of mountain ranges, streams and streets. A unique type of village grove, called bibosoop was fostered especially where the outlet of watershed was largely opened. In other cases, it was placed where a part of mountain range was relatively low, or where village residents were likely to see ugly objects such as a huge cliff, stony upland with an unvegetated area and the like(Kim and Jang 1994). In a sense, a sheltebelt is a sort of bibosoop as it is a landscape element to complement places that are exposed to strong winds. However, it is comparable to other typical bibosoop that is situated at a topographically very specific zone of watershed. In this paper, we will address potential functions of Korean village groves from a perspective of modern landscape ecology and show current status of some remnants, based on preliminary surveys. A village grove functions as barrier or filter of objects such as water, nutrients, and other elements and habitat of wildlife (park et al. 2003, Lee 2004). The village grove slows down the flow of water and air, maintains soil moisture an hinders soil erosion, enabling cultivation of crops and bringing up creatures nearby. It contributes to enhancing biodiversity. Birds rest on shrubby and woody trees of the element. Presumably, other organisms may also inhabit the village groves and take advantage of it when those move from a forest patch to others. Emerging insects acclimate themselves in the shade of the green space before they fly to sunny air. Besides the village grove acts as a component of agroforestry system as leaf litter is shed from a grove to an asjacent agricultural area, and transformed into green manure(Lee 2004). By the way, many of the landscape elements were destroyed or declined in Koea during the past several decades. The losses have been parallel or linked to environmental degradation. Unfortunately, we have a little reliable data as for how many groves have disappeared in Korea until now. There has been no complete census on the village groves in Korea, and the viewpoints of survey were to a degree different depending on surveyors. So, it is difficult to analyze the temporal and spatial change of village groves. Currently, national inventory data of Korean village groves are available in three reports. We reviewed the locations of village groves and arranged those according to the present administrative units, DONG. With the limited data, we found that at least 484 of village groves were recorded in South Korea. Among all provinces, village groves were most in Gyeongsanbuk-Do Province and least in Chungcheongbuk-Do Province(Table 1). This is a preliminary report prepared while some quantitative data regarding functions and lossers of the village groves are being collected. More detailed data will be introduced in the near future.

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.196-203
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• 2015

AbstractLiving modified organisms (LMO) are one of the most widespread products of modern biotechnology after DNA discovery. Due to the decline of grain self-sufficiency rate and the increase of reliance on LMO imports in Korea, a series of concerns with regard to safety of living modified(LM) crops has been raised. The aim of this study is to establish the detection methods for unintentional release or growing of LMO plants in environmental conditions. To detect LM crop events, general concepts of specific primer design and PCR conditions were provided by the Joint Research Centre (JRC). The certified reference materials of seven LM events (4 soybean, 2 cotton and 1 corn) were obtained from the Institute for Reference Materials and Measurements (IRMM) and the American Oil Chemists' Society (AOCS). Genomic DNA from seven LM events were purified and PCR amplifications were carried out by using individual event-specific primer sets. LM-specific PCR products of all seven events were efficiently amplified by our methods. The results indicate that the established detection method for LMOs is suitable as a scientific tool to monitor whether the crops found in natural environments are LMOs.

• Advances in Traditional Medicine
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• v.1 no.1
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• pp.8-27
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• 2000

Components of extracellular matrix and the matrix-degrading enzymes are some of the key regulators of tumor metastasis and angiogenesis. Hyaluronic acid (HA), a matrix glycosaminoglycan, is known to promote tumor adhesion and migration, and its small fragments are angiogenic. Until now, we have compared levels of hyaluronidase, an enzyme that degrade HA, in normal adult prostate, benign prostate hyperplasia and prostate cancer tissues and in conditioned media from epithelial explant cultures, using a substrate (HA)-gel assay and ELISA-like assay (Kim et al., unpublished results). The present review described an overall characterization of hyaluronidases and its application to human diseases. The hyaluronidases are a family of enzymes that have, until recently, deed thorough explication. The substrate for these enzymes, hyaluronan, is becoming increasingly important, recognized now as a major participant in basic processes such as cell motility, wound healing, embryogenesis, and implicated in cancer progression. And in those lower life forms that torment human beings, hyaluronidase is associated with mechanisms of entry and spread, e.g. as a virulence factor for bacteria, for tissue dissection in gas gangrene, as a means of treponema spread in syphilis, and for penetration of skin and gut by nematode parasites. Hyaluronidase also comprises a component of the venom of a wide variety of organisms, including bees, wasps, hornets, spiders, scorpions, sh, snakes and lizards. Of particular interest is the homology between some of these venom hyaluronidases and the enzyme found in the plasma membrane of mammalian spermatozoa, attesting to the ancient nature of the conserved sequence, a 36% identity in a 300 amino acid stretch of the enzyme protein. Clearly, hyaluronidase is of biological interest, being involved in the pathophysiology of so many important' human disorders. Greater effort should be made in studying this family of enzymes that have, until recently, been overlooked. Also, oriental medical application of the hyaluronidase will be discussed with respect to inhibition and suppression of inflammation and malignacy.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.2
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• pp.146-158
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• 2010

In order to evaluate the characteristics of sediments and pollution by organic matter and metallic elements in intertidal sediments along the southwestern coast of Korea, we measured various geochemical parameters, including the mean grain size (Mz), water content (WC), ignition loss (IL), chemical oxygen demand (COD), acid volatile sulfide (AVS), and metallic elements (Al, Fe, Cu, Pb, Zn, Cd, Cr, Mn, Hg, As), in intertidal surface sediments. The Mz of the surface sediments ranged from 2.1 to 8.3$\phi$, indicating that the surface sediments consist of various sedimentary facies, such as sand, slightly gravelly mud, sandy mud, and silt. The IL and COD in surface sediment ranged from 0.8 to 5.5% (mean $2.9\pm1.2%$) and from 3.9 to $13.8\;mgO_2/g{\cdot}dry$ (mean $8.5\pm2.6\;mgO_2/g{\cdot}dry$), respectively, which were lower than the values for surface sediment in areas near fish and shellfish farms or industrial complexes. No AVS was detected at any sampling station, despite various sedimentary facies. Most of metallic elements in surface sediments showed relatively good positive correlations with Mz and IL, which imply that the concentrations of metallic elements are mainly controlled by grain size and the organic matter content. The concentrations of metallic elements, except As, at some stations were considerably lower than those in the Sediment Quality Guideline (Effect Range Low, ERL) proposed by the National Oceanic and Atmospheric Administration (NOAA) in the United States. Similarly, the geoaccumulation index (Igeo) class indicated that pollution by metallic elements in intertidal surface sediment, except As, was moderate or non-existent. Our results imply that the intertidal surface sediments along the southwestern coast of Korea are not polluted by organic matter and metallic elements and are healthy for benthic organisms.

• Journal of Environmental Analysis, Health and Toxicology
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• v.21 no.4
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• pp.292-303
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• 2018

The particle sizes and heavy metal concentrations (Pb, Zn, Cu, Cd, Hg, As, Cr, Ni, Li, Al) of surface sediments of the Yeongsan River were analyzed to assess the distribution and pollution level of heavy metals. The distribution of particle sizes was dominated by sand in the upstream sites (MS1-MS7) and by silt loam in the downstream sites (MS8-ML3), but MS3 and MS6, located slightly upstream of the two weirs, were found to be loamy sand and silt loam, respectively. The concentrations of Pb, Zn, Cu, Cd and Hg were higher at the upstream sites, while As, Cr, Ni and Li were higher at the downstream sites. The heavy metals of crustal origin (As, Cr, Ni and Li) were strongly correlated with particle size, while the other heavy metals (Pb, Zn, Cu, Cd and Hg) were weakly correlated with particle size. Considering their concentrations, most of heavy metals were evaluated as having almost no toxic effects on benthic organisms, at all sites. In addition, anthropogenic contamination by the $I_{geo}$, EF and CF were found to have no impact at most sites, with only low levels of pollution at the others. Using the PLI method, the MS2 and MS3 sites, located upstream, were assessed to be affected by anthropogenic contamination. Most importantly, Zn, Cu and Hg were found to be the elements responsible for most pollution, and they were highest at the upstream sites, implying pollution by domestic sewage and urban discharge.

• Korean Journal of Ecology and Environment
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• v.54 no.1
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• pp.39-48
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• 2021

In order to control algal bloom, which causes environmental problems such as eutrophication in freshwater ecological environments, many attempts have recently been made using biological approaches. Among them is filtration using bivalve. Algae control with filter-feeding bivalves is emerging as an eco-friendly method. In this study, bivalves collected at Baekje weir in Geum River in Korea from Jun to Sep 2020 were tested to find out the possibility of algae control using filter-feeding bivalves through laboratory experiments. The Unio douglasiae, Anodonta woodiana, and Anodonta arcaeformis collected from Baekje weir were put into a water tank (2 L) containing Clorella vulgaris, and as a result, the average filtration rate was 95.9% per animal after 24 hrs. Calculating this with the Chl-a concentration converted to a calibration curve, it was found that the average of 154.84 ㎍ L^-1 of Chl-a was reduced. Based on this calculation, the possibility that one bivalve can eliminate Chl-a in one month is 0.0005%. It is expected that the effect is 20.14% when there are 40,000 animals. These results indirectly showed how effective bivalve's ability to control Chl-a in their habitat is. Although this study was limited to calculating the algae control ability of aquatic ecosystem based on the filtration rate of bivalve and the corresponding Chl-a reduction rate, it is thought that it will be used as basic data for integrated research from various factors and viewpoints (phytoplankton, aquatic plants, benthic organisms, and sediments) through additional research.