• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.462-470
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• 2006

The zooplankton community dynamics and grazing experiments was evaluated along a 40 km section of the lower Seomjin river system. Zooplankton was sampled twice a month from January 2005 to June 2006 at three sites (River mouth; RKO, Seomjin bridge: RK12 and Gurae bridge: RK36) in the main river channel. During the study period, the values of most limnological parameters in the three sites were fairly similar, except for conductivity. Annual variation of conductivity in River mouth and Seomjin bridge was more dramatic than which of the other site. There were statistically significant spatial and seasonal differences in zooplankton abundance (ANOVA, P<0.01). Total abundance of major zooplankton groups at both stations was much higher than in Gurae bridge. Among the macrozooplankton, cladocerans abundance was negligible in study sites during study periods. Community filtering rates (CFRs) for phytoplankton and bacteria varied from 0 to 50 mL $L^{-1}\;D^{-1}$ and from 0 to 45 mL $L^{-1}\;D^{-1}$, respectively. The spatial variation of CFRs for phytoplankton was significant (ANOVA, P<0.05). The CFRs of copepods for phytoplankton and bacteria was much higher than that of cladocerans at study sites. Total zooplankton filtering rates on bacteria were slightly lower than filtering rates on phytoplankton. The CFRs of microzooplankton (MICZ) for bacteria were much higher than for macrozooplankton (MACZ) at all sites. Considering the total zooplankton community, MICZ generally were more important than MACZ as grazers of bacteria and phytoplankton in freshwater zone, while MACZ were more important than MICZ as grazers of phytoplankton in brackish zone.

• Korean Journal of Ecology and Environment
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• v.39 no.2 s.116
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• pp.187-197
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• 2006

A mathematical modeling program called Hydrological Simulation Program-FORTRAN (HSPF) developed by the United States Environmental Protection Agency(EPA) was applied to the Yongdam Watershed to examine its applicability for loading estimates in watershed scale. It was run under BASINS (Better Assessment Science for Integrating point and Nonpoint Sources) program, and the model was validated using monitoring data of 2002 ${\sim}$ 2003. The model efficiency of runoff was high in comparison between simulated and observed data, while it was relatively low in the water quality parameters. But its reliability and performance were within the expectation considering complexity of the watershed and pollutant sources and land uses intermixed in the watershed. The estimated pollutant load from Yongdam watershed for BOD, T-N and T-P was 1,290,804 kg $yr{-1}$, 3,753,750 kg $yr{-1}$ and 77,404 kg $yr{-1}$,respectively. Non-point source (NPS) contribution was high showing BOD 57.2%, T-N 92.0% and T-P 60.2% of the total annual loading in the study area. The NPS loading during the monsoon rainy season (June to September) was about 55 ${\sim}$ 72% of total NPS loading, and runoff volume was also in a similar rate (69%). However, water quality was not necessarily high during the rainy season, and showed a decreasing trend with increasing water flow. Overall, the BASINS/HSPF was applied to the Yongdam watershed successfully without difficulty, and it was found that the model could be used conveniently to assess watershed characteristics and to estimate pollutant loading in watershed scale.

• Korean Journal of Ecology and Environment
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• v.39 no.2 s.116
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• pp.145-156
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• 2006

The objective of this study was to evaluate biological health conditions and physicochemical status using multi-metric models at five sites of the Keum-Ho River during August 2004 and June 2005. The research approach was based on a qualitative habitat evaluation index (QHEI), index of biological integrity (IBI) using fish assemblage, and long-term chemical data (1995 ${\sim}$ 2004), which was obtained from the Ministry of Environment, Korea. For the biological health assessments, regional model of the IBI in Korea (An,2003), was applied for this study. Mean IBI in the river was 30 and varied from 23 to 48 depending on the sampling sites. The river health was judged to be "fair condition", according to the stream health criteria of US EPA (1993) and Barbour et al. (1999). According to the analysis of the chemical water quality data of the river, BOD, COD, conductivity, TP, TN, and TSS largely varied epending on the sampling sites, seasons and years. Variabilities of some parameters including BOD, COD, TP, TN, and conductivity were greater in the downstream than in the upstream reach. This phenomenon was evident in the dilution by the rain during the monsoon. This indicates that precipitation is a very important factor of the chemical variations of water quality. Community analyses showed that species diversity index was highest (H=0.78) in the site 1, while community dominance index was highest in the site 3, where Opsariichthys uncirostris largely dominated. In contrast, the proportions of omnivore and tolerant species were greater in the downstream reach, than in the upstream reach. Overall, this study suggests that some sites in the downstream reach may need to restore the aquatic ecosystem for better biological health.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.544-549
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• 2000

This study was performed to compare optimum analytical method for the contents of naturally occurring sulfur dioxide in foods and to investigate the contents of sulfur dioxide in foods in order to provide a fundamental data when distinguish between added and naturally occurring sulfur dioxide. The determination of the contents of sulfur dioxide in foods from the 20 kinds, 180 cases of samples has been analyzed by the optimized Monier-Williams method, modified Rankine method and Acid Distillation/Ion Chromatography. As a result of the study, the contents of naturally occurring sulfur dioxide in foods by the optimized Monier-Williams method showed from 1.02 to 43.87 ppm and highly content of 43.87, 15.37, 11.50, 11.21 and 10.60ppm were observed in garlic, platicodon, green onion, cabbage and onion, the others were less than 10.00ppm. The sulfur dioxide contents in green onion and garlic by modified Rankine method were showed to be 2.87 and 6.14ppm, respectively, the others were detected less than 2.50ppm. The contents of sulfur dioxide by Acid Distillation/Ion Chromatography showed 15.43, 9.82, 5.74, 5.37, 2.14 and 0.49ppm in garlic, cabbage, green onion, onion, potato and apple, respectively and the others were not detected. And the contents of sulfur dioxide in green onion, onion, cabbage and garlic showed higher levels of sulfur dioxide in these foods than the others because of the naturally occurring sulfur containing compounds. The optimized Monier-Williams method, which is the of official analytical method of Korean Food Code, was suitable for monitoring of sulfur dioxide of most foods. Acid Distillation/Ion Chromatography was thought to be adequate for sulfur containing foods such as green onion, onion and cabbage. In order to distinguish between added and naturally occurring sulfur dioxide, it is though to be need of the fundamental data for the contents of sulfur dioxide in sulfite-free foods and continue the investigation for it.

• The Korean Journal of Pesticide Science
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• v.8 no.3
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• pp.231-237
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• 2004

Monitoring for the sensitivity of Colletotrichum spp. causing red-pepper anthracnose to chlorothalonil was conducted by the agar dilution method, which were isolated from infected pepper fruits in 1999 and 2002. Among the isolates in 1999 or 2002, their sensitivity to fungicide was fluctuated. Investigating the inhibitory effect of $500{\mu}g/m\ell$ of chlorothalonil on the mycelial growth of Colletotrichum isolates isolated from the infected red-pepper fruits in 1999, the frequency of isolates was 23.4%, which showed 100% of inhibitory effect on mycelial growth, and 29.7% showing below 60%. Isolates in 2002, however, showed 34.6% and 14.8% of inhibitory effect on PDAs including the same concentration of fungicide, respectively, These results showed that the sensitivity of Colletotrichum isolates in 1999 was inferior to that in 2002. According to the sampling region, isolation frequency among isolates in 2002 showing less MIC rather than 1999 was increased in Kyunggi, Kangwon, Kyungbuk and Kyungnam while the frequency of resistant isolates was done in Chungnam, Chungbuk, Cheonnam and Cheonbuk Fungicide monitoring results in this report will be of use on controlling the anthracnose in each region cultivating red-pepper.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.593-603
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• 2012

This study was carried out to investigate the ecological succession sere and conservative value, and to provide the basic data for the planning of the Provincial Park Management in Seonamsagol(Valley), Jogyesan(Mt.) Provincial Park(altitude 884m), Suncheon City, Korea by analysing the structure of the plant community. Twenty plots(size is $20m{\times}20m$) were set up at an altitude of range from 315m to 480m. As a result of analysis of TWINSPAN which is one of the ordination technique, the plant communities were divided into four groups which are community I(Quercus variabilis community), community II(Q. serrata community), community III(Decideous broad-leaved plant community), and community IV(Carpinus tschonoskii community). The warmth index is $104^{\circ}C{\cdot}month$ based on the data of monthly mean temperature during the past thirty years(1981~2010), so we found out that the vegetation of the study site located in the South Temperate Climate Zone. We supposed that the ecological succession sere of the study site is in the early stage of developing from Q. serrata community to Carpinus tshonoskii community, however we should do a long-term monitoring to investigate the changes of the ecological succession each plant community, meanwhile Sasa borealis was dominant species in the shrub layer. The diameter at breast height of specimen tree is range from 20 to 55cm(average 36cm) and the height of that is range from 14 to 35m(average 23cm). The age of community I was 64 years old, that of community II was from 59 to 64 years old, that of community III was from 51 to 62 years old, and that of community IV was from 41 to 68 years old, thus the age of the study site is about from 38 to 72 years old. According to the index of Shnnon's diversity(unit: $400m^2$), community IV was ranged from 0.8452 to 1.2312, community III was ranged from 0.8044 to 1.1404, community II was ranged from 0.8221 to 0.9971, and community I was 0.8324.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.21-27
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• 2012

This research was carried out as a survey on the contents of lead, cadmium, and arsenic in processed foods (milk, vegetable oil, and margarine) in Korea. The limits of quantification (LOQs) were Pb 0.3 ${\mu}g/kg$, Cd 0.15 ${\mu}g/kg$, and As 0.45 ${\mu}g/kg$ for milk and Pb 0.61 ${\mu}g/kg$, Cd 0.31 ${\mu}g/kg$, and As 0.91 ${\mu}g/kg$ for vegetable oil and margarine. The recoveries were 92.6-98.0% for Pb, 91.2-98.9% for Cd, and 97.9-104.7% for As. The average levels of Pb were 2.395 ${\mu}g/kg$ for milk, and 7.656 ${\mu}g/kg$ for vegetable oil. The average levels of Cd were 0.483 ${\mu}g/kg$ for milk, and 0.380 ${\mu}g/kg$ for vegetable oil, and levels of As were 0.781 ${\mu}g/kg$ for milk, and 1.241 ${\mu}g/kg$ for vegetable oil. The results of this study showed that Pb, Cd, and As contents in the whole samples were less than the maximum residual levels in the processed foods that were specified by the Codex standard.

• Journal of the Korean association of regional geographers
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• v.20 no.3
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• pp.282-299
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• 2014

Cette $\acute{e}$tude a pour objectif de d$\acute{e}$velopper le g$\acute{e}$otourisme des $\hat{i}$les de Geomun et de Baek dans le Parc Marin National de Dadohae pour conna$\hat{i}$tre les caract$\acute{e}$ristiques de cette r$\acute{e}$gion du point de vue $\acute{e}$cologique, historique et culturel $\grave{a}$ partir de ses ressources g$\acute{e}$omorphiques et g$\acute{e}$ologiques qui ont la haute de valeur $prot{\acute{e}}g{\acute{e}}e$. Il y a plusieurs ressources g$\acute{e}$omorphiques et g$\acute{e}$ologiques sur l'$\hat{i}$le de Baek: falaise; caverne marine; tafoni; le relief li$\acute{e}$ $\grave{a}$ les roches volcaniques. Il y a aussi plusieurs ressources historiques et culturels sur les $\hat{i}$les de Go et d'Est: le cimeti$\grave{a}$r d'arm$\acute{e}$e anglaise li$\acute{e}$e $\grave{a}$ l'occupation ill$\acute{e}$gale de l'$\hat{i}$le de Geomun en 1885; le site historique de Kim Ryu(金劉) qui a enseign$\acute{e}$ les disciples de confucianisme et qui a $succ{\acute{e}}d{\acute{e}}$ au Confucius; la for$\hat{e}$t de feuillus de zone $temp{\acute{e}}r{\acute{e}}e$ sur l'$\hat{i}$le d'Ouest et la ceinture de falaise sur l'$\hat{i}$le de Baek. Une route g$\acute{e}$otouristique part de l'$\hat{i}$le d'Ouest et continue $\grave{a}$ l'$\hat{i}$le d'Est: c'est la route $\acute{e}$cologique, historique et culturel sur l'$\hat{i}$le de Geomun. L'autre route continue de la c$\hat{o}$te de l'$\hat{i}$le de Baek: c'est la route de paysages g$\acute{e}$omorphiques et g$\acute{e}$ologiques. Nous proposons des plusieurs exemples pour d$\acute{e}$velopper le g$\acute{e}$otourisme des $\hat{i}$les de Geomun et de Baek: installation de centre visiteur et de panneaux d'explication g$\acute{e}$otouristique sur le g$\acute{e}$osite central ; monitoring environmental.

• Journal of Food Hygiene and Safety
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• v.19 no.1
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• pp.1-8
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• 2004

This study was executed to determine the cumulative dietary risk of PAHs exposed by food ingestion. Food samples including barbecued beef, barbecued pork, grilled chicken, ham, bacon and vegetable oil which were collected from food markets. These samples were saponified, extracted and cleaned up to purify PAHs, and then the purified sample solutions were analyzed by HPLC-FL. Generally, the levels of total PAHs in barbecued beef (0.2 ppb), bacon (0.3 ppb), barbecued pork (0.7 ppb), ham (0.8 ppb), and vegetable oil (1.2 ppb) were low, whereas the level of total PAHs in grilled chicken (9.3 ppb) was significantly high. For the exposure assessment of PAHs due to food ingestion, PAHs levels converted into TEQ$_{BaP}$, the average body weight for 20-73 age group and consumed levels of food proposed from report on the National Health and Nutrition Survey were used. The estimated lifetime average daily intake of dietary PAHs was 4.32${\times}$10$^{-4}$ $\mu\textrm{g}$-TEQ$_{BaP}$kg/day as the mean value. The dietary risk adjusted to cancer potency of benzo(a)pyrene as 7.3 (mg/kg/day)$^{-1}$ was 3.44${\times}$10$^{-6}$ based on current data.ata.

• Journal of Food Hygiene and Safety
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• v.33 no.2
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• pp.102-109
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• 2018

In the present study, a variety of polylactide (PLA) articles (n = 211) were tested for migration of lead (Pb), cadmium (Cd) and arsenic (As) into the food simulant (4% v/v acetic acid). Pb, Cd, and As were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Migration tests were performed at $70^{\circ}C$ and $100^{\circ}C$ for 30 min. The amounts of Pb, Cd, and As increased at $100^{\circ}C$ for 30 min compared with levels at $70^{\circ}C$. However, the migration at both conditions was very low. The maximum level of Pb at $100^{\circ}C$ for 30 min corresponded to 1% of the migration limit. The estimated daily intakes (EDI) based on safety evaluation ranged from $2.5{\times}10^{-5}$ to $2.0{\times}10^{-3}{\mu}g/kg\;bw/day$ for Pb, Cd, and As. The EDI calculated from migration of Pb at $100^{\circ}C$ for 30 min in PLA was the maximum value, $2.0{\times}10^{-3}{\mu}g/kg\;bw/day$, which corresponded to 0.055% of provisional tolerable weekly intake (PTWI, $25{\mu}g/kg\;bw/week$). The data from this study represent a valuable source for science-based safety control and management of hazardous heavy metals migrating from polylactide food contact materials.