• Title/Summary/Keyword: POND

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Characteristics of the Freezing and Thawing for Controlled Low-Strength Material Using Pond Ash (매립회를 활용한 저강도 고유동화재의 동결융해 특성)

  • Hyun, Hogyu;Kim, Hyungi;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.7
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    • pp.51-56
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    • 2010
  • Recently, the land area for many people has been limited because of industrialization and modernization in Korea. The large-scale constructions like the reclamation development projects have been progressed to resolve this problem mentioned above. Therefore, as many of the useful construction materials as possible are needed to perform the largescale construction projects. Many studies for the utilization of pond ash which has a similar characteristic of sand have been conducted and there has been often occurred many structural problems on roadbed in winter. Therefore, the characteristics of the freezing and thawing for Controlled Low-Strength Material(CLSM) using pond ash were analyzed and evaluated by unconfined compressive strength test and mass loss test in this study. As a result of this study, it was confirmed that new CLSM using pond ash with cement(8.2% by weight) was able to stand for the freezing and thawing behavior and was satisfied with the standard of Portland Cement Association.

Nitrate Removal Rate in Cattail Wetland Cells of a Pond-Wetland System for Stream Water Treatment (하천수정화 연못-습지 시스템 부들 습지셀의 초기 질산성질소 제거)

  • Yang, Hongmo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.5 no.6
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    • pp.24-29
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    • 2002
  • Nitrate removal rate in three cattail wetland cells was investigated. They were a part of a pond-wetland system for stream water treatment demonstration. The system was composed of two ponds and six wetland cells. The acreage of each cell was approximately $150m^2$. The earth works for the system were finished from April 2000 to May 2000 and cattails were planted in the three cells in June 2000. Waters of Sinyang Stream flowing into Kohung Estuarine Lake were pumped into a primary pond, whose effluent was discharged into a secondary pond. The reservoir was formed by a tidal marsh reclamation project and located in southern coastal area of Korean Peninsula. Effluents from the secondary pond were funneled into the three cells. Volumes and water quality of inflow and outflow were analyzed from July 2000 through January 2001. Inflow and outflow averaged $20.2m^3/day$ and $19.8m^3/day$, respectively. Hydraulic retention time was about 1.6 days. Average influent and effluent nitrate concentration was $1.98mg/{\ell}$, $1.38mg/{\ell}$, respectively. Nitrate removal rate averaged $82.6mg\;m^{-2}\;day^{-1}$. Seasonal changes of nitrate retention rates were closely related to those of wetland cell temperatures. The average nitrate removal rate in the cells was a little lower, compared with that of $125.0mg\;m^{-2}\;day^{-1}$ for the wetlands operating in North America. This could be attributed to the initial stage of the cells and inclusion of three cold months into the seven-month study period. Root rhizosphere in wetland soils and litter-soil layers on cell bottoms could not developed. Increase of standing density of cattails within a few years will establish both root zones suitable for the nitrification of ammonia to nitrates and substrates beneficial to the denitrification of nitrates into nitrogen gases, which may lead to increase of the nitrate retention rate.

Application of a Pond System to Korea for Treatment and Recycling of Wastewater (하수 처리 및 재활용 연못시스템의 국내 응용)

  • Yang, Hongmo
    • Journal of Korean Society of Water and Wastewater
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    • v.9 no.2
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    • pp.108-117
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    • 1995
  • The applicability to Korea is examined of a pond system which treats and recycles wastewaters. Air temperature and solar radiation of the pond systems at Corinne, Utah, and Eudora, Kansas, which are located in temperate regions of the U.S., are compared with those of Kimpo lying in the mid-western part of Korea. Analyzed are also $BOD_5$ and SS concentrations, algal concentrations, pH levels, and water temperature of the two systems. Air temperature of Kimpo is quite similar to that of the two systems, and solar radiation of Kimpo is more conducive than that of the systems to the growth of algae during summer. Analysis of $BOD_5$ and SS concentrations in the final effluent of the systems shows that they meet the secondary treatment standards. The study demonstrates that wastewater treatment pond system which is similar in design to the systems can be reliably utilized at Kimpo, Korea. A model is proposed which can integrate a pond system with aquaculture and agriculture.

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Algae Culture Characteristics Viewed with Continuous and Cyclic Irradiation in High Rate Algae Biomass Culture Pond (고율 조류 생세포체 배양지에서 조사 조건으로 본 조류 배양 특성)

  • 공석기
    • Journal of environmental and Sanitary engineering
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    • v.14 no.3
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    • pp.123-129
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    • 1999
  • The utilization methods of algae biomass have been studied constantly in whole world. These are $\circled1$the wastewater treatment if waste stabilization pond and oxidation ditch etc. and $\circled2$the biosorption of heavy metals and recovery of strategic' precious metals and $\circled3$the single-celled protein production and the production of chemicals like coloring agent and $\circled4$the production of electric energy through methane gasification. The culture system also has been developed constantly in relation with such utilization method developments. In the result of experimental operation under continuous and cyclic irradiation of light, using high rate algae biomass culture pond(HRABCP), which had been made so as to be an association system with the various items which had been managed to have high efficiency for algae culture, the algae production of the 12 hours-irradiance pond was 41.48 Chlorophyll-a ${\mu}g/L$ only in spite of having the more chance of $CO_2$ synthesis to algae cell than the 24 hours-irradiance pond. This means that the energy supply required for dark-reaction of photosynthesis is very important like this. The difference of algae production between continuous and cyclc irradiation explains that the dark-reaction of photosynthesis acts on algae production as the biggest primary factor. The continuous irradiance on HRABCP made the good algae-production($1403.97{\;}{\mu}g$ Chlorophyll-a/mg) and the good oxygen-production(5.8 mg $O_2/L$) and the good solid-liquid seperation. especially, DO concentration through the oxygen-production was enough to fishes' survival.

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Water characteristics and similarity analysis of wetland plant communities in 4 types of small irrigation ponds in western Civilian Control Zone in Korea (서부민간인 통제구역에서 4가지 둠벙 유형에 따른 수환경 특성과 습생식물 군집의 유사성 분석)

  • Kim, Seung-Ho;Kim, Jae-Hyun;Kim, Jae-Geun
    • Journal of Wetlands Research
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    • v.13 no.3
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    • pp.581-591
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    • 2011
  • To reveal the relationship between pond type and chemical water characteristics and wetland flora, we investigated 8 small irrigation ponds in CCZ, which represent 4 types of irrigation ponds. Cation and anion concentrations in water were low at spring type ponds and cation or anion concentrations were high at others. Especially, Kyeongeuisun pond, which is water exchanging type, had high cation and anion concentrations. This indicates that water source of this ponds is surface water. CCA showed that chemical water characteristics and wetland flora were reflected in pond types. However, water exchanging type ponds were not clustered in a group, which comes from the difference in water source and we suggest that water source should be an additional criteria to devide pond type of water exchanging.

Entering and Exiting Routes of Hynobius leechii to a Breeding Site and Staying Time within the Site

  • Sung, Ha-Cheol;Lee, Jung-Hyun;Park, Dae-Sik
    • The Korean Journal of Ecology
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    • v.28 no.5
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    • pp.237-243
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    • 2005
  • To study entering and exiting routes of male and female Hynobius leechii to a breeding site and staying time of them within the breeding site, we monitored a breeding population located in the research forests of Kangwon National University. The breeding site was surrounded by a drift fence associated with nine pitfall traps. The breeding season of this population was about one month, from 16 March to 13 April, 2005. Breeding males arrived earlier at the breeding pond than females did. The operational sex ratio (OSR), defined as the ratio of males to females which are ready to mate, over a breeding season was female-biased as 0.67 male vs 1 female (57 males vs 87 females), but daily OSRs, OSR in a particular day, within the breeding pond were male-biased with $1.36\sim7.5$ male vs f female in six days out of seven investigated days. While breeding males stayed in the breeding pond for about 11 days, breeding females left the pond as soon as they completed oviposition. However, the females stayed at terrestrial areas near the pond for about seven days before completely leaving the breeding site. Entering and exiting routes to the breeding site were different between males and females, and between ovulated and oviposited females. Both males and females arrived earlier at the breeding site stayed longer within the site. Males stayed longer within the breeding site lost more body weight.

The study of geopolymer utilization of reclaimed ash by using magnetic separation method (자력선별법을 이용한 화력 발전소 매립회의 지오폴리머 원료화 연구)

  • Kim, Kangduk
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.27 no.5
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    • pp.249-255
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    • 2017
  • Using a magnetic separation process, pond ash generated in thermoelectric power plants was separated into magnetic materials and nonmagnetic materials in order to make it into a raw material of geopolymers and unburned carbon; screening characteristics according to the particle sizes and magnet strength levels of the pond ash were observed. Based on the results of magnetic separation into fine particle (0.15~0.84 mm) and rough particle (0.84~2.4 mm) pond ash using 3000 G magnets, the weight fraction and ignition loss of nonmagnetic materials were found to be higher than those of magnetic materials, regardless of the particle size. In the case of fine particle pond ash, when the magnet strength was increased from 3000 G to 10000 G, even those materials that were weakly magnetic were separated into magnetic materials, leading to drastic increases in the weight fraction of magnetic materials, such that the ignition loss accounted for 66.9 % (22.8 wt%) of the entire ignition loss of 32.6 wt%, despite of the low ignition loss. Based on the results of measurement of the compressive strength levels of geopolymers made of magnetic-separated rough particle pond ash, the compressive strength of geopolymers made of magnetic materials containing small amounts of unburned carbon was found to be 20 MPa.

Infection status of pond smelts, Hypomesus olidus, and other freshwater fishes with trematode metacercariae in 6 large lakes

  • Cho Shin-Hyeong;Sohn Woon-Mok;Shin Sung-Shik;Song Hyeon-Je;Choi Taek-Gyun;Oh Chang-Mi;Kong Yoon;Kim Tong-Soo
    • Parasites, Hosts and Diseases
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    • v.44 no.3
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    • pp.243-246
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    • 2006
  • In order to determine the current infection status of pond smelts, Hypomesus olidus, and other freshwater fishes with trematode metacercariae, a total of 4,861 pond smelts and 18 other freshwater fishes, collected from the Soyang and Uiam Lakes in Gangwon-do, the Unam Lake in Jeollabuk-do, the Jangseong Lake in Jeollanam-do, the Uirim-ji (lake) in Chungcheongbuk-do, and the Andong Lake in Gyeongsangbuk-do, were individually digested with 1 % pepsin-HCI and examined under a dissecting microscope. In all pond smelts caught from the 6 lakes, we were unable to detect any known human infectious trematode metacercariae in Korea. However, in other freshwater fishes, such as, Squalidus japonicus coreanus (Unam Lake), and Zacco platypus (Jangseong Lake) and Opsariichthys uncirostris amurensis (Jangseong Lake), metacercariae of human-infecting trematodes, i.e., Clonorchis sinensis and Metagonimus sp. were detected, respectively.

Evaluation of Trophic State of a Small-scale Pond (Wonheung) in Ecological Park (소규모 생태연못(원흥이 방죽)의 부영양화 평가)

  • Lee, Heung Soo;Chung, Se Woong;Choi, Jung Kyu;Shin, Sang Il
    • Journal of Korean Society on Water Environment
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    • v.24 no.6
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    • pp.741-749
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    • 2008
  • Many small-scale ponds that serve as ecological habitat, recreation and irrigation are faced to eutrophication problem, which causes aesthetic nuisance and ultimately loss of their functions. Thus accurate evaluation of the trophic state of these ponds is essential to provide rational information to the stakeholders so that they can develop effective management actions. In this study, the trophic state of a small pond (Wonheung) that experiencing water quality degradation due to vicinity land development was assessed using various Trophic State Indexes (TSIs) and statistical analysis including Principal Components Analysis (PCA) based on the field monitoring data obtained from May to December, 2007. The results showed that the pond is under eutrophic state with average total nitrogen (T-N) and total phosphorus (T-P) concentrations of $708.1{\mu}g/L$ and $59.3{\mu}g/L$, respectively. The factor loading plot obtained from PCA showed distinct two influencing factors, PC 1 and PC 2. PC 1 was grouped by T-P, Chlorophyll a (Chl-a), suspended solids (SS), TN/TP ratio, and transparency that all strongly related to the eutrophication state, while PC 2 by temperature, conductivity, dissolved oxygen (DO) and turbidity that explains the seasonal water quality variations. The limiting factor was identified as light rather than phosphorus by both T-N/T-P ratio and TSI indexes analysis. The results and methodology adopted in this study can be used for water quality assessment for other small ponds and lakes.

Analyses of the Environmental Characteristics of Ponds in Golf Courses for Ecological Management (골프장 연못의 생태적 관리를 위한 환경특성 분석)

  • Ahn Deug-Soo;Kim Chang-Hwan
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.6 s.113
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    • pp.51-77
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    • 2006
  • Pond management is a critical part of overall golf course management, both during growth and maintenance modes of turf care. This study investigated 48 ponds in nine 18- or 27-hole golf courses to analyze the environmental characteristics of ponds. The research process had three phases: (1) inventory and analysis of grading plans and drainage plans, (2) field verification and interviews with greenskeepers, and (3) analyses of water quality and statistics. All data were collected from May to August in 2004. The results of this study can be summarized as follows: 1. It is desirable to site a golf course in a small watershed with high watershed eccentricity to control storm water runoff efficiently and to minimize soil erosion during construction. 2. The siting and size of a pond should be determined through a land-use analysis of the watershed for the purpose of ecological management. The bigger the forest-to-golf course ratio, the better the water quality will be. 3. The size and capacity of each individual ponds varied and there were many somewhat longish rather than round ponds. 4. There were many differences among golf courses in naturalness of the ponds, and the correlation between naturalness and area of aquatic plants was very high. 5. Analyses of pond water quality indicated that the degrees of Dissolved Oxygen, Chemical Oxygen Demanded and Suspended Solids were relatively low values but Total Phosphorus and Total Nitrogen were too high. Therefore a systematic approach is needed to solve e problem. Pesticide residues were not detected in all ponds. 6. Water depth and area of hydrophyte should be considered when designing an ecological pond. 7. All ponds used storm water as a main source of water supply and added underground water. Aquatic plants and physical methods such as water aeration and spray fountains were the main choices for maintaining a healthy aquatic environment.