• 한국환경농학회지
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• 제30권1호
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• pp.37-42
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• 2011

본 연구의 목적은 논의 중간 낙수 기간 동안 미꾸라지의 이동 특성을 살펴보는 것이다. 실험 결과, 미꾸라지는 중간 낙수 초기에는 배수로 쪽으로 수로가 형성되어 둠벙보다는 배수로 쪽으로 이동하는 경향이 있었다. 전체 표지한 미꾸라지 중 약 3.0%가 배수초기에 배수로를 통해 농업용 배수로로 이동한 것으로 나타났다. 중간 낙수가 완료되어 논에 물이 없는 시기에는 전체 표지 미꾸라지 중 5.0%의 미꾸라지가 둠벙으로 이동하여, 중간 낙수기간 동안 둠벙을 피난처로 이용한다는 것을 알 수 있었다. 실험기간동안 표식한 미꾸라지 중 논 바닥을 파고들어 가는 것은 채집되지 않았다. 둠벙이 있는 논에서는 바닥을 파고 들어가기보다는 둠벙으로 이동하는 것을 선호한 것인지 아니면 표식에 의한 스트레스로 바닥을 파고들어갈 힘이 부족했던 것인지에 대해서는 추가적인 연구가 필요하다. 둠벙과 논에서 채집한 미꾸라지의 소화관 내용물을 분석한 결과, 둠벙에서는 동물성 먹이가 86.1%, 식물성 먹이가 13.9%를 차지하여 동물성 먹이가 매우 우세하였다. 둠벙에서 채집된 미꾸라지 중 90% 이상이 먹이를 섭식하고 있었으며 10% 정도가 공복상태를 보이고 있어 표식 후 방류한 미꾸라지가 둠벙에서 정상적인 섭식 활동을 한 것으로 사료된다. 반면 논에서 채집된 미꾸라지는 모든 개체가 공복 상태를 보이고 있어 섭식활동에 장애를 받은 것으로 나타났다.

• 한국농공학회지
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• 제45권7호
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• pp.70-82
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• 2003

A pilot study was performed from July 1998 to December 2002, including winter performance, to examine seasonal performance of a constructed wetland and subsequent pond system for treatment of sewage in small communities of Korea. Pond was operated as a intermittent-discharge pond during winter period, and continuous flow system during growing season; its effects was evaluated from December 2001 to April 2003. The subsurface flow (SSF) wetland was satisfactory for treating sewage with good removal efficiency even during the winter period. The wetland effluent concentrations of $BOD_5$ and TSS were often higher in winter than in the growing season, but this was explained by the higher loading rates, rather than lower removal efficiency. The relatively poor-quality wetland effluent was further polished during winter in the pond. The upper layer of the pond water column became remarkably clear immediately after ice melt. In the growing season, ponds could be operated as a continuous flow system to remove nutrients and pathogens, and the effluent of pond could be reused as a supplemental irrigation water without risk of infection by sewage-borne pathogens as well as causing adverse effect on growth and yield. Overall, the wetland system was found to be adequate for treating sewage with stable removal efficiency, and the intermittent-discharge pond was found to be effective for further polishing if necessary. Therefore, the combination of a wetland and subsequent pond system and reuse of effluent as crop irrigation water is recommended as a practical alternative to treat sewage in Korean small communities, and partial discharge of pond water in March is suggested.

• 한국수자원학회논문집
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• 제36권3호
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• pp.385-398
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• 2003

내배수시설계획시 최대저류비에 의한 유수지 규모의 결정 방법은 이전 연구자에 의하여 제시된 바 있다. 본 연구에서는 동두천시 11개 소규모 내배수시설을 선정하여 분석한 결과, 배수면적이 작고 펌프기능이 강화된 내배수 시설에서는 강우지속기간별 우수지의 저류비의 차이는 미미하므로 최대저류비에 의한 조정지 규모의 결정은 무리가 있음을 알 수 있었다. 또한 최대저류비에 의하여 결정된 조정지 용량을 펌프에 의하여 배제되는 시간은 펌프의 허용시동간격보다 짧은 경우도 있어 펌프의 빈번한 작동을 초래한다. 그러므로 조정지는 펌프의 빈번한 작동에 의한 펌프 고장의 가능성을 피할 수 있는 규모로 결정되어야 한다. 다양한 펌프용량을 적용하여 분석한 결과, 소유역에서도 조정지의 기능이 강화된 내수배제시설에서는 최대저류비를 기준으로 한 조정지 용량의 결정은 펌프운영 측면에서 타당함을 알 수 있었다. 따라서 본 연구에서는 소규모 배수구역에서 조정지용량의 결정시 펌프의 계획배수량과 유수지의 용량에 따른 펌프의 시동빈도를 반영하여 기존의 최대저류비에 의한 방법을 개선한 방안을 제시하였다. 또한 유수지 규모와 펌프용량의 관계를 간단한 선형계획모형으로 분석한 결과, 종래의 유수지 홍수추적에 의한 유수지 용량 결정은 도시지역의 내배수시설 계획에만 타당함을 알 수 있었다.

• 태양에너지
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• 제7권2호
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• pp.22-29
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• 1987

This paper dealed with thickness variation of bottom heat sotrage zone due to salinity and flow rate of extration hot brine in small test solar pond (0.5m wide, 0.5m high, 1.0m long). Testing apparatus and situation were follows: 7.1 cm of height of suction diffuser and 1.8cm of height of discharge diffuser above the test pond respectively, 0.3cm of slot size of suction diffuser, 1.0cm of slot size of discharge diffuser, 47cm of length of the slot; heating of hot water ($75^{\circ}C$) through separated hot water tank, discharge of the brine into storage zone through discharge diffuser, the extration of the brine through suction diffuser, circulation of the extracted brine through a heat exchanger (cooler). Following results were obtained through the experiments. 1. In small test solar pond, the typical three zone which showed up in real solar pond were established. 2. Richardson Number was used more effectively to confirm hydrodynamic stability of the stratified flow. 3. The thickness of non convective layer had a great effect on the heat storage of the bottom convective layer, then the temperature of bottom convective layer had a relation to that of upper convective layer. 4. Optimum operating condition in the test pond was on 10%-15% of salt concentration and $0.05m^3/hr$ of flow rate of extraction hot brine. 5. Following thickness of 3 zones were available to obtain under optimum operation condition: o bottom storage zone: $30%{\pm}10%$ of total pond depth o non-convective zone: $40%{\pm}10%$ of total pond depth o Upper surface zone: $20%{\pm}10%$ of total pond depth.

• 한국물환경학회지
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• 제24권6호
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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.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.655-660
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• 2005

This study was carried out to evaluate of water purification in oxidation pond with filamentous algae mat. It is the water treatment process in the small rural streams to remove the organic materials and nutrients. We used the filamentous algae mat(FAM) which selectively predominate the filamentous algae to prevent the additional contamination by algae outflow. The removal efficiencies of COD, SS, T-N and T-P in Oxidation Pond with Filamentous Algae Mat were -2.5%, 84.7%, 63.9% and 89.2%, respectively. The removal efficiencies of T-N and T-P which are nutrients index were high. Results of this study would help us to determine the possibility of using the water treatment on the contaminated small rural streams.

• 농촌계획
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• 제20권4호
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• pp.13-24
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• 2014

The pond wetlands in agricultural landscape are important natural resources that carry out the function of bio-diversity conservation. However, recently, those have been gradually embedded as their utility value were disappeared. And, the assessment methods used for pond wetlands are insufficient. Therefore, this study was conducted to examine the conservation value of pond wetlands by using the modified RAM, and present the improvement of assesment methods. The study sites, a total of 32 pond of 4 types by land use, were selected on the basis of Ramsar Convention. Through the analysis of precedent studies, the weighted 8 functions were adjusted. According to the assessment results, pond wetlands made the largest contribution to Fishery and Herpetile Habitat function. In addition, it also made large contribution to Floral Diversity, Wildlife Habitat, and Water Quality Protection function. On the other hand, it made a small contribution to Aesthetics and Recreation, Runoff Attenuation, Shoreline /Stream Bank Protection, and Flood/Storm Water Storage function due to the characteristics of small-scale pond wetlands. In the assessment of 8 functions, house type showed the worst assessment result, and mountain type showed the best assessment result. It is thought that those are due to land use type in terms of vicinity. 10 items among 52 of the modified RAM showed the same assessment results in all land use types. Accordingly, it is required to be deleted and modified the assessment method. On the other hand, it is required to add age, interference, and water use to the assessment method. It is thought that these results can be utilized for the development and modification of assessment methods focused on pond wetlands in rural area.

• 한국환경복원기술학회지
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• 제4권1호
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• pp.90-97
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• 2001

For improvement of water quality, $20m^2$ of artificial floating plant islands planted with Iris pseudoacorus, were installed in small pond on March, 1999. Small pond has surface area $1,000m^2$ and mean depth 1.5 m. The density of plants was 16 per $m^2$ by using jute pot. Environmental parameters such as COD, SS, T-N, T-P and planktons were biweekly measured from 29 March to 28 September. Because of the small portion of floating island, the effect for water quality improvement was not sufficient. But considering the data of plant growth and nitrogen and phosphorus uptake capacity of plant, about 40% of coverage by artificial floating island was needed for elimination of whole nutrients from inflow.

• 한국수자원학회논문집
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• 제33권3호
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• pp.351-364
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• 2000

본 연구에서는 저류지에 의한 우수의 수질개선 효과를 모형실험에 의하여 분석하였다. 본 연구를 통하여 배수구역 출구에 저류지를 설치함으로써 합류식 관거를 통한 하수 및 강우 초기 유출수의 첨두유량과 오염도를 크게 경감시킬 수 있음을 확인하였다. 저류조 모형실험은 자연침강 저류조와 자갈접촉 저류조에 대하여 각각 실시하였다. 자연침강 저류조실험에서는 지속적으로 우수한 방류하는 경우보다는 일정시간 저류지내에 정체 후 방류하는 경우가 동일한 지체시간의 조건하에서 더 높은 오염물질 제거율을 보였다. 또한, 자갈을 채운 저류조에 대한 실험을 실시하였으며, 자연침강 저류조에 비해 전반적으로 각 오염성분에 대해 높은 제거율을 보였다. 한편, 채움재료의 표면이 상대적으로 거친 쇄석의 경우가 자갈보다 높은 제거율을 보였다.

• 한국농공학회지
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• 제44권4호
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• pp.139-148
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• 2002

Pilot study was performed to examine the feasibility of the pond system for further polishing of treatment wetland effluent from December 2000 to June 2001. The wetland system used for the experiment was highly effective to treat the sewage during the growing season, but it was less effective and its effluent was still high to discharge to the receiving water body. Therefore, the wetland effluent may need further treatment to prevent water quality degradation. Pond system could be used to hold and further polish the wetland effluent during the winter season and ots feasibility was evaluated in this study. Additional water quality improvement was apparent in the pond system during winter season, and the pond effluent could be good enough to meet the effluent water quality standards if it is properly managed. Timing of the pond effluent discharge appears to be critical for pond system management because it is a closed system and whole water quality constituents are affected by physical, chemical, and biological pond environments. Once algae started to grow in mid-April, constituents in the pond water column interact each other actively and its control becomes more complicated. Therefore, upper layer of the pond water column which is clearer than the lower layer my need be discharged in March right after ice cover melted. In the experiment, water quality of the upper water column was markedly clear in March than ant other times probably because of freezing-thawing effect. The remaining lower water column could be further treated by natural purification as temperature goes up or diluted with better quality of wetland effluent for appropriate water uses. This study demonstrated the feasibility of pond system for subsequent management of wetland effluent during the winter season, however, more study is needed for field application.