• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.27-34
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• 2008

To effectively treat the domestic sewage that was produced on a small-scale in farming and fishing village in order to encourage an ecologically friendly environment, a small-scale sewage treatment apparatus using natural purification methods that consisted of an aerobic and an anaerobic plots were constructed. The efficiency of sewage treatment according to the sewage loading was investigated to obtain the optimum sewage loading in small-scale sewage treatment apparatus. Removal rate of pollutants according to the sewage loading were in the order of $150\;Lm^{-2}day^{-1}{\fallingdotseq}300\;Lm^{-2}day^{-1}>600\;Lm^{-2}day^{-1}$. Therefore, the optimum sewage loading was 300 L m-2 day-1. Under the optimum sewage loading, removal rate of BOD, $COD_{Mn}$, turbidity, T-N and T-P were 99, 94, 99, 49 and 89%, respectively. However, to satisfy the water quality standard in effluent in small-sclae sewage treatment apparatus for domestic sewage treatment, the low removal efficiency of T-N and T-P must be improved. So to improve the removal rate of T-N and T-P, the efficiency of sewage treatment according to the improved sewage treatment process such as, re-treatment at aerobic plot, anaerobic condition of aerobic plot, changing the filter media sizes and the depths in anaerobic plot, and also addition of oyster shells to filter media at anaerobic plot were investigated. In case of 150 cm depth in anaerobic plot with filter medium A (effectivity particle size 1.50 mm) and addition of oyster shells to filter media at anaerobic plot, removal rate of T-N and T-P in both plots were increased by 10 and 3%, and 14 and 7% in comparison with 100 cm depth in anaerobic plot with filter medium B(effectivity particle size 0.95 mm), respectively. The optimum improved sewage treatment process in small-scale sewage treatment apparatus were 150 cm depth in anaerobic plot with filter medium A and addition of oyster shells to filter media at anaerobic plot.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.4
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• pp.86-99
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• 2016

This study was for analyzing the external environment and internal space structure and improving the way of use efficiency in waterfront through the Dragon boat festival to utilize waterfront actively. Through from the four target area, Hongkong, Busan, Incheon and Daejeon, this study was for an importance and satisfaction analysis for users about the element effect on the waterfront use efficiency and the contribution to cultural contents revitalization of waterfront by giving basic data. The result is as follows. First, in the importance analysis about 12 items, modern cultural infra around the waterfront was ranked highest, 8.26 and waterfront landscape, square & openspaces, convenience facilities, transport, green area, quality of viewing space, historic resources, pedestrian, suitability of width, wave, depth, water quality, berth & mooring were ranked in descending order. Second, waterfront landscape was interpreted by rather the external environmental impact according to city size than the matter of spatial structure in target area and judged as an important factor effect on site selection for waterfront. In the analysis of waterfront landscape, the reason of the high satisfaction about domestic target area was that riverside parks were recently made considering their waterfront activities. Viewing space was major infra where people could experience the pleasant waterfront and watch dynamic water leisure sports like Dragon boat three dimensionally and was thought to be improved for the use efficiency. Third, tourism resources were very important element that affect the use efficiency of waterfront, so waterfront users react sensitively to modern tourism resources rather than to historic resources. This meant that tourism infrastructure for shopping and leisure of the young affected the use efficiency of waterfront, so Hongkong and Busan were in a better position in terms of using waterfront that was near the tourism infrastructure. Fourth, in the analysis of traffic accessibility, both Hongkong and Busan were high evaluated in terms of excellent traffic accessibility by subway. Daejeon was low rated in terms of the satisfaction of use efficiency, because of the relative lower place awareness compared with transportation infrastructure. In Hongkong, waterfront was connected with downtown and in Busan, housing complex and shopping centers were located in the place for users in an easily accessible on foot, so the satisfaction was high-pitched. Finally, in the importance of water surface width and the analysis of satisfaction, except Incheon, all the three were over 200m in width of water surface and this meant the surface width above certain level was interpreted to interrupt the concentration of enjoying the water leisure sports. In the analysis of surface condition such as water quality, water depth and wave, through a survey, Busan had a problem with water quality and Gapcheon in Daejeon had a problem with optimal water depth by the festival participants.

• Journal of Korean Society on Water Environment
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• v.32 no.1
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• pp.30-35
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• 2016

Urban areas generate large amounts of stormwater and non-point source (NPS) pollutants during rainfall events. These are caused by various land use runoffs, vehicular and human activities and increased impervious cover. The increased runoff and NPS pollutants cause water quality deterioration in the receiving waters and adversely affect the aqua-ecosystem. These environmental impacts could be reduced through the application of low impact development (LID) techniques. In Korea, more than 80% of the total rainfall occurs in summer and most of these were 10 mm or less. Therefore, if the LIDs developed were able to cope with rainfall of 10 mm and below, NPS management could be efficiently conducted. This research was performed to determine the effect of varying amounts of rainfall on the performance capability of an established infiltration and filtration facility (IF facility) that can be applied to Korea's common rainfall ranges. The IF facility area was 1.75% of the catchment area, however the facility treated more than 40% and 60% runoff volume and pollutant reduction respectively for a 10 mm rainfall. Lastly, higher volume and pollutant reduction could be attained when the LID area was at least 2% of the entire catchment.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.317-324
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• 2012

To reduce non-point source pollutants in Juam Lake eco-wetlands, purification efficiencies of pollutants were investigated at three different systems. The constructed wetlands (CWs) consisted of A system, B system and C system. A system consisted of $1^{st}$ free water surface (FWS) CW, $2^{nd}$ FWS CW, $3^{rd}$ FWS CW, $4^{th}$ subsurface flow (SSF) CW and $5^{th}$ SSF CW. B system consisted of $1^{st}$ FWS CW, $2^{nd}$ FWS CW, $3^{rd}$ FWS CW, $4^{th}$ FWS CW and $5^{th}$ SSF CW. C system consisted of $1^{st}$ FWS CW, $2^{nd}$ FWS CW, $3^{rd}$ FWS CW, $4^{th}$ FWS CW and $5^{th}$ SSF CW. The concentrations of BOD, COD, SS, T-N and T-P in inflow ranged 0.20 ~ 0.91, 1.24 ~ 8.00, 0.60 ~ 8.60, 0.04 ~ 2.50 and $0.001{\sim}0.685mg\;L^{-1}$ from March to October in 2011, respectively. Removal rates of BOD, SS, T-N and T-P were high in Autumn, Spring, Spring and Summer, respectively. In A system, $1^{st}$ FWS CW, $2^{nd}$ FWS CW and $3^{rd}$ FWS CW were dominated by Leersia oryzoides. In B system, $1^{st}$ FWS CW, $3^{rd}$ FWS CW and $4^{th}$ FWS CW were dominated by Leersia oryzoides. In C system, $2^{nd}$ FWS CW and $3^{rd}$ FWS CW were dominated by Nymphaea teragona.

• Analytical Science and Technology
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• v.15 no.1
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• pp.54-66
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• 2002

In order to study systematic survey of Kumho river pollution, water analysis for 24 items was conducted at 16 sites surrounding the Kumho river system for 3 times from May 2000 to February 2001. Analytical items for the study of water quality are as follows; water temperature, pH, BOD, COD, DO, SS, electrical conductivity, oil & grease, ABS, phenol, T-P, ${PO_4}^{3-}-P$, T-N, $NH_3-N$, ${NO_2}^--N$, ${NO_3}^--N$, Cu, Zn, Cr, Cd, Mn, Fe, Pb and As. The mean values obtained for water temperature, pH, BOD, COD, DO, SS, electrical conductivity, oil & grease, ABS, phenol T-P, T-N, Cu, Zn, Fe and Mn showed $17.84^{\circ}C$, 8.04, $2.54{\mu}g/mL$, $5.64{\mu}g/mL$, $7.07{\mu}g/mL$, $8.75{\mu}g/mL$, $600.4{\mu}S/cm$, $0.19{\mu}g/mL$, $0.015{\mu}g/mL$, $0.29{\mu}g/mL$, $0.21{\mu}g/mL$, $5.22{\mu}g/mL$, $0.005{\mu}g/mL$, $0.007{\mu}g/mL$, $0.044{\mu}g/mL$ and $0.001{\mu}g/mL$ respectively. As, Cd, Cr and Pb are not detected. The mean concentration of phenol, $NH_3-N$ and $NO_2-N$ were found to be increased compared to the prior study for 3 years from January 1997 to December 1999, that of BOD, COD, SS, oil & grease and ABS were found to be decreased and the others are nearly constant. The effect of Kumho river to the Nakdong river pollution are as follows. The mean concentration of BOD changed from $1.07{\mu}g/mL$ to $1.42{\mu}g/mL$ before and after of introducing of Kumho river water respectively. The mean concentration of COD, electrical conductivity, oil & grease, ABS, phenol, T-N and T-P changed from $1.99{\mu}g/mL$, $221{\mu}S/cm$, $0.15{\mu}g/mL$, $0.006{\mu}g/mL$, $0.06{\mu}g/mL$, $2.21{\mu}g/mL$ and $0.08{\mu}g/mL$ to $2.44{\mu}g/mL$, $392{\mu}S/cm$, $0.16{\mu}g/mL$, $0.015{\mu}g/mL$, $0.07{\mu}g/mL$, $2.81{\mu}g/mL$ and $0.19{\mu}g/mL$ respectively.

• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.366-373
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• 2000

Toxin production and low digestibility of cyanobacteria are known to cause low exploitability of cyanobacteria by zooplankton. In this study, we compared relative tolerance and compatibility of zooplankton taxa in eight eutrophic lakes, exposed to frequent cyanobacterial blooms, uring the summer season of 1999. Microcystis, Anabaena, Oscillatoria and Phormidium were common cyanobacteria in all lakes. with relatively lower $NO_3-N$ concentration (<0.2 mgN/l) and TN/TP ratio (<20), compared with other lakes where colonial cyanobacteria dominated. Rotifers were dominant zooplankton in most lakes, and among them, Keratella, Polyarthra and Hexathra were common. The laboratory feeding experiment showed that relative copepods that greatly decreased (90%) after 4 day when cyanobacteria were used as the food source of zooplankton, while rotifers gradually increased with the change of dominant taxa from Keratella through Pompholyx to Monostyla. These results suggest that rotifers may be capable of coexisting with cyanobacteria by exploiting them for the food source.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.3
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• pp.129-140
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• 1998

In this study two sites were selected to investigate groundwater contamination and spatial relationship between pollution level and its source. One is the Asan area, agricultural district where pollution sources are scattered. The other is the Gurogu area of Seoul city, industrial district where industrial complex and residential areas are located. Groundwater samples collected from these districts were analysis for chemical constituents. The attribute value files of the chemical constituents of groundwater and the spatial layers have been constructed and the pollution properties have been investigated to find out spatial relationships between the groundwater constituents and pollution sources using CIS. Relatively high contents of Si and HCO$_3$ in groundwater from the Asan area reflect the effect of water-rock interaction, whereas high contents of Cl, NO$_3$, SO$_4$and Ca in groundwater from the Gurogu area are due to the pollution of various sources. Pollution over the critical level of Korean Dinking Water Standard has been investigated from 15 sampling sites out of 40 in the Asan area, and 33 sampling sites out of 51 in the Gurogu area. There is pollution of NO$_3$, Cl, Fe, Mn, SO$_4$and Zn in groundwater from the Gurogu area, and that of NO$_3$, SO$_4$and Zn in groundwater from the Asan area. Principal pollution in both areas is NO$_3$contamination. Deep groundwater from the Asan area is not contaminated with NO$_3$except for one site and most of shallow groundwater near the potential point sources such as factory and stock farm is contaminated seriously. Groundwater from the Gurogu area has been already polluted seriously considering the fact of contamination of deep groundwater. This study reports a spatial relationship between the pollution level and pollution source using GIS.

• Korean Journal of Microbiology
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• v.30 no.4
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• pp.322-331
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• 1992

In order to understand the transfer and behavior of R gene in water environments. the Kmr gene in the genetically modified microorganisms(GMMs) w,is studied by conjugation. The plasmid variously rearranged in the conjugants were comparatively analyzied by agarosc gel electrophoresis and the specific Km' genes in the gel were tletected with DNA probe. The Kmr genes of the GMM strains(DKC600 and DKC601) were transferred at higher rate than those of natural isola~e(DKI)b, ut the ratc was a little diflurent depending upon the recipient strains. Rearrangement of the plasmids appeared morc drastic in GMM strains than in IIKI as donor. The transfer frequencies of the Km' genes in LR broth were remarkably higher than in the water of AW and FW without regards to the strains. In LA breth. the frequencies of Kmr genes were higher at 25'C-30$^{\circ}$C than at 10$^{\circ}$C and at pH - 7 than pH 9, but temperature and pH of the FW did n,,t affect to the frequency. And the conjugants from GMM strains in FW did not showed any plasmids. except tor 43 kb plasmiil. As results of Southern analysis of the plasmid, variously rearranged in eonjugant cells obtained in LB broth, the Kmr genes were detected at the same position of Km' plasrnids of the donor cell(DK1 and GMM strains). But Km' plasmid disappeared in the conjugants obtained in F'W and their chronlosomes showed strong signal of hybridization. The Kmr plasmid of DKl in the conjugants obtained in FW water was transferred and maintained its size, but the Kmr plasinids of the GMM strains were all integrated into chromosome. Therefore, the Kmr plasmids of DKI anit GMM strains in LH were intactly transferred and other plasmitls were variously rearranged. but Km' gene of DKC600 in FW water was integrated into the chromosorn: without regards to the temperature and pH of the water.

• Korean Journal of Environmental Agriculture
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• v.31 no.2
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• pp.122-128
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• 2012

BACKGROUND: Mine drainage from metal mining districts is a well-recognized source of environmental contamination. Oxidation of metal sulfides in mines, mine dumps and tailing impoundments produces acidic, metal-rich waters that can contaminate the local surface water and soil. METHODS AND RESULTS: This experiment was carried out to investigate the pollution assessment of heavy metal on the water quality of mine drainage, paddy soils and sediment in lower watershed affected by mine drainage of the Sambo mine. The average concentrations of dissolved Cd (0.018~0.035 mg/L) in mine drainage discharged from the main waste rock dumps(WRD) was higher than the water quality standards (0.01 mg/L) for agricultural water in Korea. Also, the average concentrations of dissolved Zn, Fe and Mn were higher than those of recommended maximum concentrations (Zn 2.0, Fe 5.0, Mn 0.2 mg/L) of trace metal in irrigation water proposed by FAO (1994). The average contents of Pb and Zn in paddy soils was higher than those of standard level for soil contamination(Pb 200, Zn 300 mg/kg) in agricultural soil by Soil Environmental Conservation Act in Korea. Also, the concentrations of Cd, Pb and Zn in sediment were higher than those of standard level for soil contamination (Cd 10, Pb 400, Zn 600 mg/L) in waterway soil by Soil Environmental Conservation Act in Korea. The enrichment factor (EFc) of heavy metals in stream sediments were in the order as Cd>Pb>Zn> As>Cu>Cr>Ni. Also, the geoaccumulation index (Igeo) of heavy metals in stream sediments were in the order as Zn>Cd>Pb>Cu>As>Cr>Ni, specially, the geoaccumulation index (Igeo) of Zn (Igeo 3.1~6.2) were relatively higher than that of other metals in sediment. CONCLUSION(s): The results indicate that stream water and sediment were affected by mine drainage discharged from the Sambo mine at least to a distance of 1 km downstream (SN-1, SN-2) of the mine water discharge point.

• Applied Microscopy
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• v.38 no.2
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• pp.141-148
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• 2008

Nitric oxide (NO) is an important regulator of renal blood flow, glomerular hemodynamics, and tubule transport processes in the kidney. There is also evidence that NO is involved in cell cycle regulation and mitotic division. During development the nNOS expression pattern differs from that observed in adult animals. However, little is known about temporal and spatial patterns of nNOS expression in the developing kidney. The purpose of this study was to establish the time of expression and the distribution of nNOS in the developing rat kidney. Kidneys from 14-, 16-, 17-, 18-, and 20-day-old fetuses, 1-, 4-, 7-, 14-, and 21-day-old pups, and adult animals were preserved and processed for immunohistochemistry. In the adult kidney, nNOS was detected in the parietal epithelium of Bowman s capsule, macula densa, descending thin limb and inner medullary collecting duct. nNOS immunoreactivity appeared first in the distal tubule anlage at 15 days of gestation, and in all epithelial cells of developing thick ascending limbs (TAL) as well as macula densa of 17- and 18-day-old fetuses. From 20 days of gestation to 14 days after birth, nNOS was expressed in the newly formed cortical TAL, which are located in the medullary ray, whereas in mature TAL of juxtamedullary nephrons, nNOS immunolabeling gradually decreased in intensity and became restricted to the macula densa. In inner medullary collecting ducts, nNOS immunoreactivity appeared first at 7 days after birth in the papillary tip and gradually ascended to the border between outer and inner medulla. In the descending thin limb and parietal epithelium of Bowman's capsule, weak nNOS immunoreactivity was observed at 14 days after birth and labeling gradually increased to adult levels at 21 days after birth. These results suggest that differential expression of nNOS in the developing kidney is an important physiological regulator of renal function during kidney maturation.