• Journal of Environmental Impact Assessment
• /
• v.29 no.3
• /
• pp.157-181
• /
• 2020

Sediments from rivers, lakes and marine ports serve as end points for pollutants discharged into the water, and at the same time serve as sources of pollutants that are continuously released into the water. Until now, the contaminated sediments have been landfilled or dumped at sea. Landfilling, however, was expensive and dumping at sea was completely banned due to the London Convention. Therefore, this study applied contaminated sedimentation soil of 'Royal Palace Livestock Complex' as soil purification method. Soil remediation methods were applied to pretreatment, composting, soil washing, electrokinetics, and thermal desorption by selecting overseas application cases and domestically applicable application technologies. As a result of surveying the site for pollutant characteristics, Disolved Oxigen (DO), Suspended Solid (SS), Chemical Oxygen Demand (COD), Total Nitrogen (TN), and Total Phosphorus (TP) exceeded the discharged water quality standard, and especially SS, COD, TN, and TP exceeded the standard several tens to several hundred times. Soil showed high concentrations of copper and zinc, which promote the growth of pig feed, and cadmium exceeded 1 standard of Soil Environment Conservation Act. In the pretreatment technology, hydrocyclone was used for particle size separation, and the fine soil was separated by more than 80%. Composting was performed on organic and Total Petroleum Hydrocarbon (TPH) contaminated soils. TPH was treated within the standard of concern, and E. coli was analyzed to be high in organic matter, and the fertilizer specification was satisfied by applying the optimum composting conditions at 70℃, but the organic matter content was lower than the fertilizer specification. As a result of continuous washing test, Cd has 5 levels of residual material in fine soil. Cu and Zn were mostly composed of ion exchange properties (stage 1), carbonates (stage 2), and iron / manganese oxides (stage 3), which facilitate easy separation of contamination. As a result of applying acid dissolution and multi-stage washing step by step, hydrochloric acid, 1.0M, 1: 3, 200rpm, 60min was analyzed as the optimal washing factor. Most of the contaminated sediments were found to satisfy the Soil Environmental Conservation Act's standards. Therefore, as a result of the applicability test of this study, soil with high heavy metal contamination was used as aggregate by applying soil cleaning after pre-treatment. It was possible to verify that it was efficient to use organic and oil-contaminated soil as compost Maturity after exterminating contaminants and E. coli by applying composting.

• Korean Journal of Ecology and Environment
• /
• v.33 no.2 s.90
• /
• pp.128-135
• /
• 2000

The authors surveyed the seasonal variations of environmental factors, the distributions of heterotrophic bacteria and Anabaena cylindrica growth-inhibiting bacteria at each water layer in Daechung Reservoir to verify the role of bacteria during the extinction of bloom. Average water depth at site 1, 2, and 3 were 25.5 m, 15.0 m and 12.3 m, respectively. Water temperature showed a typical pattern seasonally. The variation of DO was relatively inverse proportional to that of water temperature, although it was irregular during summer time. DO decreased gradually to early May, fluctuated sharply after then, and followed by gradual increasement after middle of September. This variation pattern was notable at surface layer. There was remarkable difference in DO concentraion between surface layer and the other water layers during the period in which DO irregulary varied. The variation range of chlorophyll-a concentraion at surface layer in summer time was broad, and it was relatively high when DO was high. The population size of heterotrophic bacteria was high from Spring to Autumn, an declined after September when the water temperature droped rapidly. Especially this variation pattern was prominent at the surface layer. Bacteria that inhibit the growth of A. cylindrica was almost not detected by June, and its distribution increased in July. Afterward, it showed different variation pattern between each site. The distribution of A. cylindrica growth-inhibiting bacteria was higher at the middle and bottom layer than the surface layer in July and October, when it was larger at all sites for the study period. This result suggests that the antagonistic bacteria exhibit higher activity when host activity drops. These results also suggest that natural water bacteria control the distirbution of cyanobacteria, especially its activity as controller is remarkable when cyanobacterial growth declines.

• Journal of Environmental Impact Assessment
• /
• v.26 no.6
• /
• pp.404-417
• /
• 2017

In this study, we analyzed response patterns of rotifer community to eutrophic state, and estimated the applicability of rotifer community as an environmental indicator for highly eutrophicated reservoirs. In order to evaluate the relationships among spatial and temporal distributions and the water quality of rotifer community, we selected the Jundae Reservoir and Chodae Reservoir in Chungcheongnam-do, Korea, which are geographically adjacent but have different water quality, particularly in their eutrophic states. For the analyses on their correlations, monthly survey of water quality and rotifer community, was conducted from April to November 2013 in both reservoirs. The rotifer community was divided into different compositions of functional groups as well as species. Functional groups were classified according to the structure and shape of trophi which can represent feeding behavior of rotifer genus. To reflect ecological characteristics of species, body size and habitat preferences were also considered. Species-based composition did not show a consistent tendency with water quality parameters related with eutrophication. On the contrary, functional group composition showed relatively clear group-specific patterns, increasing or decreasing according to the parameters. The results suggest the possible application of rotifer functional group composition as an indicatorforthe lentic systems, especially hyper-eutrophicated reservoirs. The present study can suggest the applicability based on the field observations from the limited time scale and sites, and further studies on feeding behavior of the rotifer functional group and its interactions with environmental variables are necessary for the further application.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.35 no.2
• /
• pp.115-121
• /
• 2002

To develop a new method of conjugation and to determine the distribution of R plasimds, we isolated multi-drug resistant strains from fish pathogenic bacteria in the farms of south and east seacoasts of Korea. Out of the 134 isolates examined, 10 showed resistance to chloramphenicol, tetracycline, streptomycin, ampicillin, colistin, nalidixic acid, oxolinic acid and kanamycin. One out of 10 multi-drug resistance bacteria, Vibfio damsela JE1 (V. damsela JE1), contained transferable R plasmid of chlorarnphenicol- tetracycline resistance genes and other nucleic acids encoding ampicillin and kanamycin resistance. The presence of the R plasmid was confirmed by conjugation using the chromocult medium (CC) as a selective and differential medium for transconiugants with identification based on the growth or colors of the colonies. The frequency of R plasmid transfer with filter mating method was come out much higher than that of broth mating method and appeared to be dependent upon the mating time and temperature. The optimum conditions for filter mating method were found to be 30$^{\circ}C$ and 24hrs as mating temperature and period, respectively, Moreover, donor cells with R plasmid, both isolate and standard bacteria, were shown to have an ability to transfer the plasmid against Escherichia coli K-12 HB101 (E. coli HB101) and Edwardsiella tarda (E. tarda) RE14 at fairly high frequencies, finally, we isolated 3 isolates of Sphingomonas sp., carrying R plasmid from 12 multi-drug resistant bacteria in normal microflora of the flounder (Paralichthys olivaceus) group used for the isolation of V emsela JE1 four months before. The same size and gene transfer chayateristics of R plasimds with those of V damsela JE1 confirmed that normal microflora have the reservoir activity for R plasmid in natural aquatic environment.

• The Korean Journal of Quaternary Research
• /
• v.14 no.1
• /
• pp.7-31
• /
• 2000

Quaternary Geological and geophysical investigation was performed at the Eurimji reservoir of Jaechon City in order to interprete depositional environment and genesis of lake sediments. For this purpose, echo sounding, bottom sampling and columnar sampling by drilling on board and GPR survey were employed for a proper field investigation. Laboratory tests cover grain size population analysis, pollen analysis and $^{14}C$ datings for the lake sediments. The some parts of lake bottom sediments anthropogenically tubated and filled several times to date, indicating several mounds on the bottom surface which is difficult to explain by bottom current. Majority of natural sediments were accumulated both as rolling and suspended loads during seasonal flooding regime, when flash flow and current flow are relatively strong not only at bridge area of the western part of Eurimji, connected to stream valley, but at the several conduit or sewage system surrounding the lake. Most of uniform suspend sediments are accumulated at the lake center and lower bank area. Some parts of bottom sediments indicate the existence of turbid flow and mudflow probably due to piezometric overflowing from the lake bottom, the existence of which are proved by CM patterns of the lake bottom sediments. The columnar samples of the lake sediments in ER-1 and ER-3-1 boreholes indicate good condition without any human tubation. The grain size character of borehole samples shows poorly sorted population, predominantly composed of fine sand and muds, varying skewness and kurtosis, which indicate multi-processed lake deposits, very similar to lake bottom sediments. Borehole columnar section, echo sounding and GPR survey profilings, as well as processed data, indicate that organic mud layers of Eurimji lake deposits are deeper and thicker towards lower bank area, especially west of profile line-9. In addition the columnar sediments indicate plant coverage of the Eurimji area were divided into two pollen zones. Arboreal pollen ( AP) is predominant in the lower pollen zone, whreas non-aboreal pollen(NAP) is rich in the upper pollen zone. Both of the pollen zones are related to the vegetation coverage frequently found in coniferous and deciduous broad-leaved trees(mixed forest) surrounded by mountains and hilly areas and prevailing by aquatic or aquatic margin under the wet temperate climate. The $^{14}C$ age of the dark gray organic muds, ER1-12 sample, is 950$\pm$40 years B.P. As the sediments are anthropogenetically undisturbed, it is assumed that the reliability of age is high. Three $^{14}C$ ages of the dark gray organic muds, including ER3-1-8, ER3-1-10, ER3-1-11 samples, are 600$\pm$30 years B.P., 650$\pm$30 years B.P., 800$\pm$40 years B.P. in the descending order of stratigraphic columnar section. Based on the interpretation of depositional environments and formation ages, it is proved that Eurimji reservoir were constructed at least 950$\pm$40 years B.P., the calibrated ages of which ranges from 827 years, B.P. to 866 years B.P. Ancient people utilize the natural environment of the stream valley to meet the need of water irrigation for agriculture in the local valley center and old alluvium fan area.

• Korean Journal of Environmental Biology
• /
• v.28 no.2
• /
• pp.86-94
• /
• 2010

This study compares and contrasts the dynamics of plankton in 31 temperate lakes and reservoirs, and considers particularly the biomass ratio of zooplankton to phytoplankton and ecological model application. A total of 89 species of zooplankton were identified (70 rotifers, 14 cladocerans and 5 copepods) and a total of 554 species of phytoplankton were identified (176 Bacillariophyceae, 237 Chlorophyceae, 68 Cyanophyceae, and 73 other algal taxa). The total plankton abundance and species diversity were showed distinctive spatial and seasonal variation. Annual average phytoplankton density was $7,350{\pm}15,592$ cells $mL^{-1}$ (n=124), and the lowest was $855{\pm}448$ cells $mL^{-1}$ (n=4), while the highest was $72,048{\pm}13,4631$ cells $mL^{-1}$ (n=4). For zooplankton, small rotifer groups dominated the study sites, and approximately 3~10 species appeared in the study sites. Statistical analysis and an ecological model application revealed that the size of reservoirs affected the structure size of plankton community, i.e. relatively large number of species were found in smaller reservoirs. From this result, we can conclude that management strategy for the reservoir environment has to be focused more on small-size reservoirs, in terms of plankton community ecology.

• Journal of Korean Society of Environmental Engineers
• /
• v.35 no.5
• /
• pp.312-320
• /
• 2013

Particulates in drinking water distribution system (DWDS) are mostly influenced by internal corrosion of metal pipes and sediment in pipelines due to the solution of this effect is limited. The particle size, component and properties of compounds for particulates in distributed water are different and the difference of these characteristics will be occurred by the kind of facilities, pipe condition, external factors and supply system etc. In this study, conducting the investigation of water quality in DWDS researches with particulates in the water. Monitoring sites were each water supply reservoir and the end of water supply area in DWDS. To collect particulate material at each sampling site, $47{\phi}$ glass microfiber filter type GF/C was performed using a filtration. Substances that the effect of the turbidity in the water according to particulate suspended solids and inorganic materials is due to the increasing particulates in the end of DWDS were increased. The result of compounds analysis by using X-ray diffraction (XRD) were Goethite (${\alpha}$-FeOOH), Magnetite ($Fe_3O_4$) in the end of DWDS and Quartz ($SiO_2$), Yeelimite ($Ca_4Al_6O_{12}SO_4$) at the effluent of waterworks and reservoirs. There were differences the compounds and sediments in the releasing or remaining water distribution facilities.

• Korean Journal of Ecology and Environment
• /
• v.42 no.3
• /
• pp.404-406
• /
• 2009

This study note wished to introduce special-purpose ship for algae removal that is developed by core technology of our country. The ship is consisted of main frame and adjuvant that can attach and detach as cross (+) shape of a character. The characteristics of ship are super light weight and low draft. That is consisted of four devices as suction, collection, filtration and recovering units. Among these, filtration used screen filter (mesh size 30 ${\mu}m$). Also, can separate and remove water and algae by compression air participle notion. Percentage of moisture content of concentrated algal particle was 85%. Water parted with algae finally is exhausted to water area. Removal efficiency that compare by chlorophyll-$\alpha$ concentration was about 57% (inflow: 83.2 ${\mu}g\;L^{-1}$, outflow: 35.8 $[\mu}g\;L^{-1}$) without physical and chemical pretreatment. Forward, need to achieve effect test in various conditions (algal biomass, flow etc.) for efficiency and technological elevation of exclusion device. We wished to contribute in presuppression system construction of massive algal development that manage blue-green algae occurrence area effectively, and prevents spread as lower part of reservoir.

• Korean Journal of Ecology and Environment
• /
• v.51 no.1
• /
• pp.29-39
• /
• 2018

Long-term variation of zooplankton community and species composition was studied from 2003 to 2014 in a deep reservoir, Lake Soyang, in monsoon climate region, Korea. In addition, we examined the correlation with environmental factors. Annual precipitation of watershed showed a large variation in the $705{\sim}1,779mm\;yr^{-1}$ and more than 70% of it was being concentrated from June to September. The water quality of Lake Soyang was shown a clearly seasonal variations and particularly turbid water flowing into the lake during rainy season was the most important environmental factors. Zooplankton community in Lake Soyang showed a significant difference before and after 2006. Zooplankton biomass has shown a large increase and also showed a change in the zooplankton community structure since 2006. The of zooplankton showed positive correlation with temperature and BOD, Chl. a, TP concentration. These results are considered that nutrient and organic matter contained in the turbid water influences the increase in zooplankton biomass and species composition. However, water quality was limited to account for the increase in biomass of zooplankton. For example, increase of small zooplankton density (rotifer; Keratella cochlearis, Polyarthra vulgaris) in spring which is dominated by diatoms (large size; Melosira, Synedra etc.) is considered as a bottom-up effect by the microbial loop. And increased density of crustaceans in autumn was considered a top-down effects by the relationship between predator and prey of microzooplankton and mesozooplankton. In other words the inflow of allochthonous organic matter during rainy season also affected to zooplankton food web in Lake Soyang. In conclusion, biomass, diversity and long-term variations of zooplankton in Lake Soyang were determined by physico-chemical factors but also it is considered that biological interactions is important.

• Journal of Life Science
• /
• v.17 no.1 s.81
• /
• pp.97-104
• /
• 2007

Present study aims to investigate the effect of muddy water on gill and kidney tissues and blood components of Opsariichthys uncirostris amurensis in Imha reservoir. As a result of observing the gill tissues in muddy water with light and scanning electron microscopes, the edema, the exfoliation of epithelial cells and fusion of the secondary lamellae were observed. The space between gill lamellae was irregular, and a lots of muddy debris around the secondary lamellae were observed. In case of kidney tissues, the size of glomerulus was smaller and thickness of basal membrane was broader and the empty space in Bowman's capsule was wider than those of the control. The blood cells of O. uncirostris amurensis in muddy water were increased in number. Of the white blood cells, acidophilic granulocytes were highly distributed, and the shapes were irregular. Among the plasma components, the concentration of TP, ALB, A/G ratio, TG, CHOL, and AST were low, whereas that of the inorganic materials was high. Based on the above results, it is considered that muddy water possibly involves in the decrease of respiratory and excretory rates, giving rise to secondary lesion of tissues.