• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.4
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• pp.261-270
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• 1998

This study was carried out in order to investigate the distribution and species composition of benthic polychaetous community in northern Kyeonggi Bay in September 1995. Mean density of benthic animals was 557 indiv./$m^2$. Benthic polychaetes were the most dominant faunal group, comprising 60 species with a mean density of 488 indiv./$m^2$. Benthic polychaetes were most abundant in Yumha Channel centering on Incheon Harbor, whereas relatively poor in the intertidal zones fringing Yongjong Island and Songdo area, and in the offshore main channel. The most dominant polychaete was Heteromastus filiformis (47.3% of polychaetous community), followed by Nephtys palybranchia, Tharyx sp., Sternaspis scutata and so on. Kyeonggi Bay could be divided into 4 regions from cluster analysis based on the dominant species composition: offsea/channel region, Incheon Harbor, intertidal zone of Yongjong Island, and intertidal zone of Songdo area. Highest species number and diversity index (H') were recorded at offsea/channel region, whereas highest faunal density at Incheon Harbor. Incheon Harbor was characterized by high abundance of H. filiformis. Compared with the previous studies carried out in Kyeonggi Bay, faunal density and species number have little changed for the recent 10 years. Dominant species was different between each study, but has been among opportunistic species of small-sized polychaetes belonging to capitellids, cirratulids or spionids. These results indicate that Kyeonggi Bay has been organically polluted steadily; specifically, this study reveals that Incheon Harbor has been the center of pollution and that the benthic community in the outer sea off Sihwa dike has become unstable.

• Korean Journal of Ecology and Environment
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• v.43 no.2
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• pp.232-241
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• 2010

Epilithic diatom communities and water quality were monitored to evaluate the ecological impact of the inflow of Wonju-stream passing through the urban area in the Seom River Watershed. We selected the 14 sampling stations (5 main stream sites and 9 tributary sites), and collected diatom and water samples between October 2007 and September 2008, on the seasonal basis. The results indicate that most water quality parameters showed the site-specific patterns over the study, except for water temperature and dissolved oxygen. The levels of water quality parameters were highest at the site of Wonju stream, whereas the lowest in the upstream sites, and intermediate or gradually decreased in the downstream sites of the Seom river. One species, Achnanthes convergens, showed the highest biomass and frequency over the sites, while three saprophilous species-Navicula goeppertiana, Navicula subminuscula, Nitzschia palea were appeared only in Wonju Stream and other polluted sites. According to trophic diatom index (TDI) values, which were highly correlated with nutrients and EC, the study sites were classified into three classes: upstream and tributary (Class A and B), Wonju Stream (Class D), and mixed zone and downstream (Class C). A cluster analysis supported the result of TDI classification. Therefore, Wonju-stream located in populated urban area exerted the adverse ecological effects on the epilithic diatom community and water quality of the lower Seom River System, although its severity gradually decreased downstream.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.6
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• pp.399-412
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• 2005

This study investigated the composition and the distribution of the benthic polychaeta community in the semi-enclosed Yoja Bay on the southern coast of Korea and was designed to deduce temporal changes in the community with the comparison of the previous studies. In YoJa Bay, benthic polychaetous community structure was investigated on the base of the samples from 87 stations. The surface sediment was mainly composed of fine-grained sediment, mixed clayey silt and silty clay. The total benthic macrofaunal density was $387 indiv./m^2$, and the density was higher in the middle bay, and in the mouth of bay than in the inner bay. scapharca subcrenata (Bivalvia) and amphipods (Crustacea) were important species in the inner and the middle of the bar, respectively. Benthic polychaetes were comprised of 72 species with a mean density of $149 indiv./m^2$. Their distributions showed higher densities in the mouth of bay than in the rest of bay. The dominant species over 1.0 percentages were composed of the 20 species, and they occupied $84.5\%$ of the total density. The most dominant species was Sternaspis scutata ($13.6\%$), fallowed fly Heteromastus filiformis ($9.8\%$), Polynoidae indet. ($8.3\%$), Sigambra tentacuzata ($7.1\%$) and others. The cluster analysis revealed that the study area was divided into three station groups. At the station group YI located in the inner bay, the most dominant species was Heteromastus filiformis . At the station group YII in the middle bay, the dominant species was Sternaspis scutata. And at the station group YIII in the mouth of bay, the dominant species was Paraiacydonia paradoxa. Whereas Sternaspis scutata and Mediomastus sp. were the dominant species in the past study, Heteromastus filiformis and Tharyx sp. appeared newly to be the dominant species, even if their low densities that in the past. These facts mean that Yoja Bay be maintained yet as little polluted area compared to other bays on the coast of Korea, but needed some caution of marine environmental management.

• Journal of Korean Home Economics Education Association
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• v.19 no.3
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• pp.119-131
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• 2007

This study was to investigate the recognition level of food safety from high school students(264 male, 276 female) in Chuncheon area using questionnaires. The results of the survey are summarized as follows : Regarding the general consciousness of the conditions of food safety, the proportion of the students who worry about it is higher, while 40.0% respond they are not concerned with it. The information pertinent to food safety was usually acquired from the mass media. As a fundamental reason responsible for the food safety accidents, they pointed out deficient sense of responsibility of the personnels who produce, distribute, and sell food products. As the most problematic materials threatening food safety, they pointed out heavy metals(24.8%), and subsequent responses were environmental hormones(24.4%), food additives(17.0%). The foods, for which they are most concerned about residual pesticides, were vegetables and fruits. High proportion of the students perceived that agricultural products are not safe from residual pesticides, and most of the students(92.4%) thought that residual pesticides are bad for their health. The examination on the food safety influenced by heavy metals reveals that 87.4% of the students thought the materials do influence food safety. As the food kind that is likely to be most polluted by heavy metals, they pointed out fishery products. The highest concern about processed food stuffs was the food additives. Most of the students thought that the containers of processed foods may be toxical. 25% of the students are more seriously considering food safety when they buy foods. High proportion of the students who responded they confirm safety-related matters at the time of food purchase thought much of food safety, while high proportion of those who didn't confirm those matters lay a great importance on the taste.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.1
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• pp.54-64
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• 2006

The traditional Korean diet, which is high in rice and vegetables, is fast being replaced by a Western style diet as the standard of living goes up. In addition to this, cigarette smoking has taken on serious proportions, especially amongst those of the younger generation. Because Seoul (and it's surrounding areas) is the hub of Education and Business, it is densely populated and heavily polluted Consequently health-related issues and diseases are starting to resemble those prevalent in Western communities. Historically, stomach cancer was the #1 killer-disease in Korea, but nowadays lung cancer ranks either 1st or 2nd on the list of killer-disease in Korea. This is presumably due to the lethal combination of heavy smoking and pervasive air pollution. Despite these disquieting facts, almost no study had been made of the nutritional patterns and dietary habits of smoking and non-smoking young adults in the Seoul area. Therefore the purpose of this study is to compare the dietary and nutritional patterns of young smokers with those of young non-smokers in and around Seoul. This is done with regards to their eating habits and lifestyles, as well as the dietary components that contribute towards maintaining good health. The results showed that compared to non-smokers, smokers manifested irregular eating patterns and also tended to overindulge on fast- or junk foods. In contrast to this, non-smokers enjoyed a healthier diet, which was high in brown rice, grains, legumes, fresh fruit and vegetables, and 'kimchi'. Amongst the male subjects of this study, it was found that smokers consumed significantly less vitamin $B_2$, calcium, and phosphorous than non-smokers. It was also established that in general, stress-generated smoking habits were formed during the high school years of the younger generation. In conclusion: Because smokers maintain a less healthy diet and life-style, it is to recommended that a 'Health Education Program' be developed which could guide young smokers into adopting better dietary habits and life styles.

• Korean Journal of Agricultural Science
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• v.26 no.2
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• pp.61-69
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• 1999

The water quality of river has been deteriorated mainly by both point source pollution and nonpoint source pollution from the watershed. Techniques to cut point source pollutants down to the level required have been developed. But, techniques of best management practices to catch the nonpoint source pollutions and to control the routine of pollutants were not successively developed. The quality of closed water system such as reservoir, lake and farm pond is irresistable to being polluted mainly by nonpoint source pollutions. In this study, the population, land use, runoff coefficient, amount of rainfall, and runoff discharge in the watershed were surveyed to investigate the characteristics of water quality such as BOD, COD, SS, T-N, and T-P. After studying the changes of water quality in the viewpoint of land use such as paddy land, residential area, upland, forest and meadow, load factors of nonpoint source pollutant were calculated in Bangdong reservoir watershed. Residential area was more severe than other land use as far as BOD, COD and SS concerned. T-N and T-P released from the paddy and upland were higher than other land use. The 45.9% of total load of nonpoint source pollution was occured during the rainy season.

• The Korean Journal of Ecology
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• v.25 no.4
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• pp.253-259
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• 2002

Application of phytoremediation in the polluted area to remove undesirable materials is a complex and difficult subject without detailed investigation and experimentation. We investigated the accumulation patterns of cadmium and lead in plants naturally grown, the bioavailability of plants to accumulate these toxic metals and the responses of P. thunbergii to cadmium and lead. The soil samples contained detectable lead (＜$17.5_\mu$g/g), whereas cadmium was not detected in the soils of study area. The whole body of Persicaria thunbergii contained detectable lead (＜320.$8_\mu$g/g/g) but cadmium was detected only in the stem (＜7.$4_\mu$g/g/g) and root (＜10.$4_\mu$g/g/g) of P. thunbergii. Cadmium was not detected in Trapa japonica and Nymphoides peltata, whereas lead was detected in T. japonica (＜323.$7_\mu$g/g/g) and N. peltata (＜177.$5_\mu$g/g/g). Correlation coefficient between lead content in soil and in these plant samples represented positive correlation. The total content of lead in each plant sample increased in the order of N. peltata$\leq$P. thunbergii

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.6
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• pp.699-709
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• 2017

We measured the grain size, total organic carbon (TOC), total nitrogen (TN), and heavy metals (As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, and Zn) in order to understand the spatial distribution and pollution level of organic matter and metals in surface sediment around Goseong Bay, a shellfish farming area, Korea. The surface sediments were composed of finer sediments such as mud and clay. The concentration of TOC, TN, and heavy metals were much higher in the innermost bay than in the mouth and outside of bay. The spatial distribution of organic matter and heavy metals and C/N ratio (5-10) in sediment showed that the organic matter and heavy metals in sediment of the study region were significantly influenced by oceanic origin organic matter and anthropogenic sources, respectively. Based on the results of four assessment techniques (sediment quality guideline, geoaccumulation index, pollution load index, ecological risk index), the sediments around the Goseong Bay were a little polluted for heavy metals and the high metal concentrations in the northern region of bay could adverse impact on benthic organisms in sediment. Thus, the systematic management plan for the improvement of water and sediment environment and the concentrated monitoring of pollutants for sustainable aquaculture and seafood safety around Goseong Bay are necessary in the future.

• The Korean Journal of Quaternary Research
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• v.32 no.1_2
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• pp.1-29
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• 2018

We investigated the seasonal variation of diatoms from the modern bottom floor sediments of the reservoirs distributed in the southern part of the Korean Peninsula. The studied reservoirs include each three reservoirs from Southeastern part, Central Southern part and Southwestern part, respectively, to compare the dominant diatom assemblages that are ecologically controlled by local environments. In the Southeastern region, Aulacoseira spp., Fragilaria crotonensis, Fragilaria tenera, Gomphonema gracile, G. parvulum and Gyrosigma attenuatum were dominant species. Aulacoseira spp., Cymbella tumida, Cymbella turgidula, Diploneis finnica and Fragilaria crotonensis were dominant taxa in the Central Southern regions. In the southwestern region, Aulacoseira spp., Fragilaria crotonensis, Gomphonema parvulum and Stenopterobia curvular were predominated. Of which Aulacoseira spp. were predominant species at all reservoirs. In addition most of dominants are saproxenous taxa living in the clean water area, and the water quality of these reservoirs is considered to be less polluted water. As a result of seasonal comparison of diatom productivity, the first productivity is higher in summer than in winter. However, diatom valve abundance in the southeastern reservoirs was fewer from the samples collected at May than February.

• Journal of the Korean earth science society
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• v.21 no.5
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• pp.611-622
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• 2000

To investigate the exchange rates of mercury(Hg) across soil-air boundary, we undertook the measurements of Hg flux using gradient technique from a major waste reclamation site, Nan-Ji-Do. Based on these measurement data, we attempted to provide insights into various aspects of Hg exchange in a strongly polluted soil environment. According to our analysis, the study site turned out to be not only a major emission source area but also a major sink area. When these data were compared on hourly basis over a full day scale, large fluxes of emission and deposition centered on daytime periods relative to nighttime periods. However, when comparison of frequency with which emission or deposition occurs was made, there emerged a very contrasting pattern. While emission was dominant during nighttime periods, deposition was most favored during daytime periods. When similar comparison was made as a function of wind direction, it was noticed that there may be a major Hg source at easterly direction to bring out significant deposition of Hg in the study area. To account for the environmental conditions controlling the vertical direction of Hg exchange, we compared environmental conditions for both the whole data group and those observed from the wind direction of strong deposition events. Results of this analysis indicated that the concentrations of pollutant species varied sensitively enough to reflect the environmental conditions for each direction of exchange. When correlation analysis was applied to our data, results indicated that windspeed and ozone concentrations best reflected changes in the magnitudes of emission/deposition fluxes. The results of factor analysis also indicated the possibility that Hg emission of study area is temperature-driven process, while that of deposition is affected by a mixed effects of various factors including temperature, ozone, and non-methane HCs. If the computed emission rate is extrapolated to the whole study area we estimate that annual emission of Hg from the study area can amount to approximately 6kg.