• Economic and Environmental Geology
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• v.39 no.6 s.181
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• pp.689-697
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• 2006

Distribution and speciation of arsenic in water resources was investigated in the Ulsan mine area. In 62% of uoundwater samples from the mine area, total As concentrations exceeded 0.05 mg/l, the Korean Drinking Water Standard. As(V) was the major type in groundwater with minor As(III). Arsenic species appeared to be in transition stages following redox changes after exposure to the air through the monitoring wells. In areas around the mine, the mine and Cheongog spring appeared to be the sources of arsenic contamination of water resources. The spring showed 0.345 mg/1-As, as much as seven times of the Korean standard. Groundwater and stream samples showed As-concentrations greater than 0.05 mg/l in 30% and 33% samples, respectively, and 60 and 67% of samples exceeded 0.01 mg/l of WHO guideline, respectively. Again, As(V) was a dominant species, however, several samples had As(III) in appreciable levels. In one stream sample, organic species including DMA and AsB were detected in low levels, probably resulted from transformation or related biogeochemical processes.

• Journal of environmental and Sanitary engineering
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• v.10 no.1
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• pp.45-65
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• 1995

Seasonal occurrences and dynamics on the freshwater algae were examined in the upstream of the Yongsan river system with the Kwangju service water area from 1993 to 1994. Three hundred and three taxi were totally collected and composed of 6 classes, 15 orders, 7 suborders, 31 families, 74 genera, 248 species, 48 varieties and 7 forma. Compositions in each algal class were divided in 136 taxi of Chlorophyceae(44.8% ), 109 taxi of Bacillariophyceae(36.0% ), 30 taxa of Cyanophyceae(10.1% ), 21 taxa of Euglenophyceae(6. 9% ),4 taxi of Chrysophyceae(1.3% ) and 3 taxa of Dinophyceae(1.0% ). The occurrence of taxa was a markedly decrease(-62) between summer and autumn, the critically increase(+43) between spring and summer. And also, it was indicated that the high frequency of taxa in summer, but the high standing biomass In winter in spite of low taxi. In general, it has much algal biomass in station 9 and 10, but low in station 4, 5 and 11, relatively. Through this survey, the major dominant taxa in algal biomass, Microcystis aeruginosa, Melosira varians, Synedra ulna and Navicula cryptocephala, they were all above 2.1×10$^{6}$ce11s/1, 13.2% of totals. There are about 10% of new emigrated taxa by season and they showed a remarkable succession. We may suggested that this system was well sustained for the habitat of freshwater algal community with low dominance and high diversity. Twenty three of nuisance algae including of Microcystis aeruginosa, Peridinium willei and Anabaena flos-aquae were distributed as if had low appearance. Of course, many of them were saprobiontic taxa, extraordinary growttung groups depend on organic loading in water system and also it was not showed severe algal blooming phenomenon.

• Journal of Korean Society on Water Environment
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• v.26 no.2
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• pp.261-267
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• 2010

In order to evaluate the distribution level of Cryptosporidium and Giardia in drinking water resources, distribution of Cryptosporidium and Giardia was studied in intake water of main water treatment facility with treatment capacity over 50,000 ton/day in Korea. 10 L samples from each study sites were collected quarterly for 2 years between Oct. '04 and Dec. '07. Cryptosporidium and Giardia were filtered and concentrated by capsule filter and centrifugation, and analyzed by immunomagnetic separation process and fluorescent assay. Cryptosporidium oocysts and Giardia cysts were detected in 7.0% and 9.3%, respectively, of a total 776 samples from 97 study sites. And mean detection number of Cryptosporidium oocysts and Giardia cysts in total 776 samples was 0.11/10 L, 0.16/10 L, detection range of Cryptosporidium oocysts and Giardia cysts was 0~7/10 L, 0~4/10 L, respectively. In seasonal distribution, Cryptosporidium was more frequent in spring as 9.2% than other season, Giardia was more frequent in winter as 14.6% than other season, but there was not shown significant seasonal characteristics. In correlation analysis with total 776 data, Cryptosporidium had significant correlation to total coliforms at the 0.05 level, but correlation value was too low as 0.07 (r=0.07). In case of Giardia, what had significant correlation at the 0.05 level was total coliforms and fecal coliforms, but correlation value was too low as 0.26, 0.27 respectively.

• Journal of Preventive Medicine and Public Health
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• v.19 no.2 s.20
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• pp.273-280
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• 1986

'Medicinal water' have been used for the treatment of disease and the promotion of health. To study the quality and health effect of 'medicinal water', the eleven springs located near Taegu City during the period of March 27-February 17, 1986 were tested for biological and physiochemical examination and were checked for sanitary environment around the spring. Among them three springs (27.3%) had a good sanitary equipments and only one was negative for biological examination. Three 'medicinal warer' were accepted as potable by physicochemical examination. According to above findings, all of the 'medicinal water' sampled from the springs located near Taegu City were not potable by this sanitary survey adopted Drinking Water Standard in Korea. Kachang and Youngchum 'medicinal water' were more contaminated by heavy metals and bacteria than those of other springs. To solve the problem of contamination by heavy metals that originated from uncertain sources, we should search for the sources of water contamination, remove it completely and also support the environmental equipments and management system in protection of safe 'medicinal water' supply.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.71-77
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• 2015

Much attention has been focused on the activity of the natural antioxidants present in fruits and vegetables, because potentially these components may reduce the level of oxidative stress. Especially, mulberry leaves containing many natural components are considerable resource for natural antioxidants. The antioxidant capacity of mulberry leaves was investigated with minilum L-100 device and ARAW-KIT (anti-radical ability of water-soluble substance), in comparison to the ascorbic acid. The antioxidant capacity of 16 varieties was 3303.4 nmol at opening stage of five leaves in spring. The highest stage of antioxidant capacity (3708.0 nmol) and yield rate was just before the coloration stage with anthocyanin in fruits, whereas the lowest stage was middle of June (2231.6 nmol) and about two months growing stage after summer pruning (2064.6 nmol). But after summer pruning, the antioxidant capacity of mulberry leaves increased gradually until just before fallen leaves stage. Even if samples were same variety, antioxidant effect of those showed different results according to collected regions. Also, antioxidant effect of mulberry leaves were higher than that of branches. The antioxidant capacity of yield-type mulberry leaves and fruits (Morus alba L., M. bombycis Koidz, and M. Lhou (Ser.) Koidz) collected from In-je, Won-ju and Yang-yang regions, Kang-won province, Korea, was investigated. The results indicated that total antioxidant capacity of yield-type mulberry leaves was 2711.2 nmol. In the antioxidant capacity analysis of Jeollabuk-Do genetic resources, autumn's mulberry leaves showed higher antioxidant capacity than that of spring's it. To investigate the effect of tea on antioxidative capacity, five kinds of tea(coffee mix, green tea added brown rice, mulberry leaf tea, Polygonatum odoratum tea and black tea added lemon) were selected and analyzed. Their's anti-oxidative capacity were 2,531.01 nmol, 1,867.42 nmol, 1,053.72 nmol, 292.71 nmol and 188.91 nmol, respectively. The antioxidative capacity of drinking water soaked with mulberry leaf showed 891.96 nmol.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.538-544
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• 1985

This study was carried cut to evaluate the water quality of spring waters in Pusan area(see Fig. 1). In this experiment, twenty-five water samples were collected from 5 stations from December 1983 to August 1984. Range and mean values of constituents of the samples are as follows: pH $5.80{\sim}7.25$, 6.60; water temperature $6.0{\sim}23.0^{\circ}C,\;12.9^{\circ}C$; total residue $33.0{\sim}325mg/l$, 121.2mg/l; alkalinity $4.75{\sim}51.6mg/l$, 24.1mg/l; hardness $9.47{\sim}85.0mg/l$, 30.3mg/l; electrical conductivity $0.495{\sim}2.750{\times}^2{mu}{\mho}/cm,\;1.239{\times}10^2{\mu}{\mho}/cm$;turbidity $0.54{\sim}7.80$NTU, 2.04NTU; $KMnO_4$ consumed $0.51{\sim}8.47mg/l$, 1.96mg/l; chloride ion $4.91{\sim}36.0mg/l$, 12.55mg/l; fluoride ion ND-0.30ppm, 0.08ppm; nitrate-nitrogen ND-8.94mg/l, 1.94m:g/l; nitrite-nirogen ND-0.10mg/l, 0.03mg/l; ammonia-nitrogen ND-0.16mg/l, 0.03mg/l: phosphate-phosphorus ND-0.09mg/l, 0.03mg/l; silicate-silicious $0.42{\sim}22.7ng/l$, 7.96mg/l; copper ND-10.5ppb, 2.46ppb; lead ND-22.7ppb, 3.54ppb; zinc ND-103ppb, 21.33ppb; iron $20.3{\sim}2,800ppb$, 801.72ppb, respectively. Arsenic, cyan, cadmium, manganese, mercury, chrome and phenol were not detected. Total residue, electrical conductivity, turbidity and chloride ion of station 1 (Milrakdong) were higher than others as 178.1mg/l, $2.127{\times}10^2{\mu}{\mho}/cm$, 3.16NTU and 16.32mg/l. The concentration of silicious had a great influence on precipitation. The concentration of fluoride ion of spring waters was lower as 0.08ppm than the criterion for drinking water as 1ppm, while iron was exceed 2.7 times as 801.72ppb.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.418-430
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• 2017

The quality of surface water is a very important issue to use various demands like as drinking water, industrial, agricultural and recreational usages. There has been an increasing demand for monitoring water quality of many rivers by regular measurements of various water quality variables. However precise and effective monitoring is not enough, if the acquired dataset is not analyzed thoroughly. Therefore, the aim of this study was to estimate differences of seasonal and regional water quality using multivariate data analysis for each investing tributaries in Han River. Statistical analysis was applied to the data concerning 11 mainly parameters (flow, water temperature, pH, EC, DO, BOD, COD, SS, TN, TP and TOC) for the time period 2012~2016 from 12 sampling sites. The seasonal water quality variations showed that each of BOD, TN, TP and TOC average concentration in spring and winter was higher than that of summer and fall, respectively. In summer each flow rate and average concentration of SS was higher than any other seasons, respectively. The correlation analysis were explained that EC had a strong relationship with BOD (r=0.857), COD (r=0.854), TN (r=0.899) and TOC (r=0.910). According to principal component analysis, five principal components (Eigenvalue > 1) are controlled 98.0% of variations in water quality. The first component included TP, DO, pH. The second component included EC, TN. The third component included SS. The fourth component included flow. The last component included Temp. Cluster analysis classified that spring is similar to fall and winter with water quality parameters. AnyA, WangsA, JungrA and TancA were identified as affected by organic pollution. Cluster analysis derived seasonal differences with investigating sites and better explained the principal component analysis results.

• 한국해양학회지
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• v.7 no.1
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• pp.24-45
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• 1972

The Han River is an important water source in Seoul and neighbouring districts, for public and industrial supply, and for agriculture and fishery. Nowadays, more than six million inhabitants are supplied withe water from this river. The total length of the river is 470km, and has 17 10$\^$9/㎥ an average annual flow. The hydrographic characteristics at Seoul are 653㎥/sec in an average flow, 4,608㎥/sec in the maximum average flow, and 201㎥/sec in the minimum average flow. These are influenced in some degree by snowmelt in early spring, and greatly by the flood during summer. For the pollution problems, the periods of low flow are critical ones. As a rule they occur around the months November through June. Nowadays, most of the sewage from towns and industries is discharged untreated. Apart from domestic and industrial sewages, there are some discharges of mineral matter by mines in the upriver region. In general, water quality of the Han River is kept very clean and healthy until Kwangnaru of the upper region of Seoul. A large pollution, however, is received in the downstream by the domestic and industrial sewages of Seoul. It can be seen that dissolved oxygen, COD and BOD$\sub$5/ diminish markedly, and the intensity of almost every water parameter of the river continues to increase. Comparison of the figures for 1971 derived from a sampling point 40km downstream of Kwangnaru leads to the conclusion that hardness, Ca and Mg were no changed; alkalinity, Si and soluble- Fe were slightly increased; CO$\sub$2/, acidity, Cl, NO$\sub$2/-N, Cu, Zn and Al were increased in 2 and 3 times; total residue, total ignitious residue, COD, BOD$\sub$5/, NH$\sub$4/-N, PO$\sub$4/-P, Mn, Pb and total-Fe were increased in 4 to 7 times; and SO$\sub$4/, particulate-Fe and Cd were increased in 10 to 11 times. On the other hand, coliforms were increased in 650 times; fecal coliforms in 365 times; enterococci and total plate counts in 30 times, respectively. In view points of water quality standards, the down Han River water is now leveling out in Cd, coliforms and fecal coliforms for the agricultural use; in dissolved oxygen and some trace elements (Cu, Zn, Pb and Cd) for the fishery use; in ammonia, COD, BOD$\sub$5/, and Cd for the drinking use.

• Journal of Forest and Environmental Science
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• v.29 no.1
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• pp.15-28
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• 2013

Protected area based ecotourism is now the most interesting topic to the nature lover and policy maker throughout the world because of its linkage with economic benefits, protected area management and biodiversity conservation. Based on this premise our study explores the visitors' perception on the recreational potential of Kaptai National park and its potentiality in ecotourism development in Bangladesh. The field survey was carried out both in holidays and non-holidays of the week from the late winter season in 2009 to the spring season in 2010. A total of 118 visitors were interviewed with the help of a semi-structured questionnaire. Study findings revealed that about 62% male constitute the visitors group with the maximum number of visitors in the age of between 15-25 years (35.59%). The tourists were very much attracted by boat riding (93.22%) followed by scenic beauty of Rampahar-Sitapahar (85.59%). A major portion of about 57.14% tourists wished to visit the park within a year because they got a lot of pleasure from Natural and green environment (86.44%) followed by boating on Kaptai Lake (85.59%). Most of the visitors (36%) were happy about existing facilities but defined some problems such as tour guiding facility, food and drinking water supply, etc. About 71% and 66% respondents perceived that Kaptai National Park made them to be concerned and protective of nature and supports and sustains local ecosystem respectively and 43% respondents agreed that Kaptai National Park ensures the social equity and involve local people in ecotourism which are the most important elements of sustainable ecotourism. The present study results also predict that the park might be a good recreational area for enjoying with family members and group of friends through proper management and promoting the relationships among tourism, local people and biodiversity conservation.

• Toxicological Research
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• v.18 no.1
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• pp.13-22
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• 2002

In Korea, 2,320 tonnes of acetanilide were mostly wed as intermediates for synthesis in phar-maceuticals or additives in synthesizing hydrogen peroxide, varnishes, polymers and rubber. Only small amount of 120 kg were wed as a stabilizer for hydrogen peroxide solution for hair colouring agents in 1998. Readily available environmental or human exposure data do not exist in Korea at the present time. However, potential human exposures from drinking water, food, ambient water and in work places are expected to be negligible because this chemical is produced in the closed system in only one company in Korea and the processing factory is equipped with local ventilation and air filtering system. Acetanilide could be distributed mainly to water based on EQC model. This substance is readily biodegradable and its bioaccumulation is low. Acute toxicity of acetanilide is low since the L $D_{50}$ of oral exposure in rats is 1,959 mg/kg bw. The chemical is not irritating to skin, but slightly irritating to the eyes of rabbits. horn repeated dose toxicity, the adverse effects in rats were red pulp hyperplasia of spleen, bone marrow hyperplasia of femur and decreased hemoglobin, hematocrit and mean corpuscular hemoglobin concentration. The LOAEL for repeated dose toxicity in rats was 22 mg/kg/day for both sexes. Acetanilide is not considered to be genotoxic. In a reproductive/developmental toxicity study, no treatment-related changes in precoital time and rate of copulation, impregnation, pregnancy were shown in all treated groups. The NOAELs for reproduction and developmental toxicity (off-spring toxicity) are considered to be 200 mg/kg bw/day and 67 mg/kg bw/day, respectively. Ecotoxicity data has been generated in a limited number of aquatic species of algae (72 hr- $E_{b}$ $C_{50}$; 13.5 mg/l), daphnid (48hr-E $C_{50}$ > 100 mg/l) and fish (Oryzias latipes, 96hr-L $C_{50}$; 100 mg/l). Form the acute toxicity values, the predicted no effect concentration (PNEC) of 0.135 mg/1 was derived win an assessment factor of 100. On the basis of these data, acetanilide was suggested as currently of low priority for further post-SIDS work in OECD.in OECD.D.