의사결정지원기법을 이용한 농촌유역 통합수질관리모형의 개발

권순국 서울대학교 농업개발연구소 1999 농업생명과학연구 Vol.3 No.-

A decision support system(DSS-WQMRA) is developed to support the water quality management for various pollutants in rural areas. The DSS-WQMRA consists of four submodels such as a GIS, a database, water quality simulation models and a decision model. In the system, the GIS shows location of pollutants. The database manages each data and supplies input data that are required to operate various models. The water quality simulation model is composed of GWLF, PLCM and WASP5. The decision model using mixed integer programming can determine optimal costs and specific methods of wastewater treatment to satisfy selected water quality standards. The DSS-WQMRA is written in JAVA. The DSS-WQMRA was applied to the Bok-ha watershed. It was proved that DSS-WQMRA could be very useful tool for water quality management in rural areas.

小流域의 流出豫測을 위한 數學的 模擬發生 模型

權純國 서울大學校 農科大學 1983 서울대농학연구지 Vol.8 No.2

Modifications were made to the Standford Wastershed Model(SWM), which was a deterministic, lumped, hydrologic simulation model, in an effort to adopt the model to the geophysical and hydro-meteorologicak conditions in Korea. The resulting modified model was evaluated its potentital applicability of predicting water yields from a watershed, which were essential to the design criteria for agricultural water resource development projects in the pennisula. The hydrologic simulation model herein provides long-term runoff for different hydrological and meteorological conditions. Two experimental watershed under IHP project were selected and their hydrological data were tested with the model. However, it was found that the data had some limitations on the accuracy as well as the length of records, which was important for the simulation. Runoff is a synthetic response from a watershed to various hydrological input. Thus, the comprehensiveness of hydrological data and the accuracy of runoff data are all a prerequisite for proper evalutions of the hydrologic system. They are even more important for the applivations of a simulation approach to runoff processes on a small watershed. The runoff from a small watershed fluctuates in a relatively short period of time, and necessiates at most hourly measurements. Furthermore, It seems necessary that runoff data be continuously menitored with self-recording stage gauges. The results form this paper demonstrate that any application of advanced hydrologic approches like a simulation model should follow a program for adequate and reliable measurements of hydro-meteorological data. Once appropriate data bases are established, a deterministic watershed model would be possible to provide hydrologic information. The information may be further used for the development, management, and utilization of agricultural water resources. Data bases can also be accurately extrapolated to ungaged watersheds using appropriate hydrological parameters.

농촌지역 오폐수처리용 한국형 Biofilter System 개발

권순국 서울대학교 농업개발연구소 2000 농업생명과학연구 Vol.4 No.-

Biological wastewater treatment using a fixed film reactor is the aerobic system which utilizes biofilm developed on the surface of the filter medium to oxidize the carbonaceous organics in the sewage. New technology is called Absorbent Biofilter System where absorbent filter medium with open cell type of polyethylene foam to maximize the treatment efficiency is filled in the aeration container. In this study, Korean Type Biofilter System(KTBS) has been developed by improving the design of a commercial biofilter system. It is consisted of an anaerobic septic tank to remove solids and an absorbent biofilter to oxidize carbonaceous organics more effectively. A series of bench scale as well as pilot plant experiments were conducted to evaluate carbonaceous organics and nutrients removal efficiencies. With this efficient system, we can attain treated BOD and TSS concentration less than 10 mg/L which is to meet the water quality standard in the Special Region in Korea. Moreover, with the introduction of new operational scheme using alternate anoxic/oxic recirculation process in this system, high removal efficiencies over 70% for both T-N and T-P were attained. Since the KTBS adopted biological wastewater treatment using the biofilm reactor and unique operational scheme to maxmize the treatment efficiencies, and a method of packed tower aeration, it was thought to be a competitive alternative and ideal method to treat wastewater in Korean rural communities considering the cost-effectiveness, stable and excellent performance, and minimum maintenance. We also provide the standard design for KTBS from the experimental results. It is expected that the KTBS will become a standard method for decentralized on-site wastewater treatment provided a remote monitoring system of maintenance and temperature raising facilities during cold winter period. Futhermore, it may also contribute to improving the living envirnment as well as the water quality in Korean rural communities if disseminating nationwide.

降雨特性을 이용한 降雨에너지 算定에 관한 硏究

盧載卿,權純國 서울大學校 農科大學 1984 서울대농학연구지 Vol.9 No.2

It is known that the amount of soil erosion and infiltration is greatly affected by the energy of a rainstorm. However, the energy of a rainstorm can not be measured directly and/or ana1yzed accurately due to the continuous variations of raindrop size distribution and intensities in time and space. The raindrop size distribution data in this study were obtained by using an apparatus that provided a continuous measurement of raindrop size distribution. The measured data were then used to calculate the rainstorm energy. From the result of analysis of the relationship between raindrop characteristics and the rainfall energy, the following results were obtained. 1. Various rainstorm characteristics were evaluated from the raindrop size distribution data of 801 items for a duration of one minute. As the rainfall intensity increased, the median size of raindrops and rainfall kinetic energy also increased with some variations. 2. The relationship between median drop size and rainfall intensity was obtained by regressional analysis from the rainfall data obtained as follows. log??D??=0.073+0.115 log?? I 3. The relationship between kinetic energy of rainfall and rainfall intensities was proved as a logarithmic regressional equation. log??KE=1.08+0.136 log?? I However, a curve showing the value of lower limit of rainfall kinetic energy at various rainfall intensities could be represented by the following equation. log??KE=0.820+0.258 log?? I

시화호 인공습지의 식물 플랑크톤과 갈대 부착조류 군집의 동태

김용재,권순국 한국환경농학회 2004 한국환경농학회지 Vol.23 No.1

인공습지를 이용한 오염수 처리를 위해 조성된 시화 인공습지의 개방수 정점에서 식물플랑 크톤과 갈대 조성지의 정점에서 갈대 부착 조류 군집의 동태에 대한 연구를 위해 5개의 정 점을 선정하여 2001년 10월부터 2002년 6월까지 조사를 실시하였다. 반월천으로부터 유입된 오염수는 정점 1을 통해 갈대군락을 관류하면서 정점 2에서 저감 효과를 나타내었다. 총인/ 총질소 비는 모든 정점에서 16이상을 약간 상회하였다. 본 수계는 인이 제한 영양염으로 작용하는 것으로 나타났다. 식물플랑크톤은 총 413종류로 서 375종, 21변종, 2품종 및 15미동정이었다. 현존량은 330∼36,420 cells/mL의 범위로 정점 5에서 최저였고 정점 1에서 최대였다. 현존량은 정점 1과 2, 정점 3과 4를 관류하면서 영양 염류와 같이 감소되는 경향을 나타내었다. 엽록소 농도는 2.5∼170.7 ㎍/L의 범위로 정점 1 에서 최대였고 정점 5에서 최저였다. 엽록소 농도 역시 유입수부터 습지 관류후의 정점에서 뚜렷한 차이를 나타내었다. 우점종은 Euglena oblonga, Synura spinosa 등 14종류였으며 정 점 1과 2에서는 부영양수역에서 출현율이 높은 종으로 조성되어 있다. 갈대 부착조류는 총 329종류로서 295종, 13변종, 3품종 및 17미동정동으로 구성되어 있다. 종수는 녹조강-규조강 ㄹ-남조강-유글레나강-황갈조강의 순으로 조사되었다. 상대빈도는 정점 간에 약간의 차이는 있지만 계절적으로 남조강-규조강-녹조강으로 변화하였다. 생체량인 엽록소 농도는 5.5∼ 363.8 ㎎/㎡의 범위로서 정점 4에서 최저였고 정점 2에서 최대였다. 본 요인은 정점 1에서 2 그리고 정점 3에서 4로 관류된 후에 증가하는 경향을 나타내었다. 우점종은 총 16종류로서 조사 초기에는 Lyngbya angusta 등 남조강이 조사되었고 이후에는 Stigeodonium lubricum 등 녹조강과 규조강의 Nitzschia palea 등도 조사되었다. 본 조사에서 식물 플랑크톤의 종수, 현존량 및 엽록소 농도는 유입 정점에서 높았으며 습지를 관류 된 후에 감소하였다. 갈대 부착조류는 유입 정점보다 습지 관류 후에 증가하는 경향을 나타내었는데 이것은 습지를 관 류하면서 부유물질 등이 습지를 통해 제거됨으로서 부착조류의 생육을 개선시킨 것으로 나 타났다. The Shihwa constructed wetland was established for the treatment of severely polluted water from Banwoul, Donghwa and Samhwa stream. This study was focused on investigating dynamics of phytoplankton communities in open waters and periphytic algae on reed (Pluragrrites communis) planting area at 5 stations from October 2001 to July 2002. The concentration of T-N and T-P of inlet stations from the stream were decreased by flowed through the wetland However, the TN/TP ratios at all stations were shown as a little over 16 indicating that the T-P will play some role as a limitation factor. Phytoplankton communities were identified as a total 413 taxa which were composed of 375 species, 21 varieties, 2 forma and I5 unidentified species. Standing crops of phytoplankton communities and chlorophyll-a concentrations ranged from 330 - 36,420 cells/mL and 2.5-170.7 ㎍/L respectively, and showed the decreasing tendency after flowing through the wetland at almost all stations Dominant species were 14 taxa at all stations which were Euglea oblonga and Synura spinosa etc. Periphytic algae on the reed were a total 329 taxa which were composed of 295 species, 13 varieties, 3 forma and 17 unidentified species. The species numbers were recorded in order of Chlorophyceae - Bascillariophyceae - Cyanophyceae - Euglenophyceae - Chrysophyceae. The relative abundance (%) was showed a seasonal variation from Qanophyceae to Baseillariophyceae and to Chloyphyceae. Chlorophyll-a concentrations, ie. the biomass of periphytic algae were ranged from 5.5-363.8 ㎎/㎡. Dominant specie were 16 taxa which were Lyngbya angusta of Qanophyceae in the early investigation, and were changed to Stigee clorrium lubricum of Chlorophyceae, and Nitzschia palea of Bacillariophyceae etc. in the late. Species number, standing crops and chlorophyll-a concentrations of phytoplankton and perphytic algae were shown higher value at the inlet station? than the stations after flowing through the wetland.

Drop box weir의 水理特性에 關한 硏究

吳壽勳,權純國 서울大學校 農科大學 1986 서울대농학연구지 Vol.11 No.1

This study was intended (1) to estimate the accurate stage discharge relationship through field measurement on a weir located at the outlet of the Sangrim watershed, (2) to investigate the reliability of the stage-discharge relationship of the Sangrim Drop-box weir in relation to the approach angles of flow and the stream slope and the maximum probable sedimention using the fixed bed model and the movable bed model tests respectively, (3) to find a new stage gaging point which would supplement the gaging point which it currently used (G-1), and finally, (4) to find the usage limit of the Drop-box weir for other hydrologic studies of the watershed. The results of the study can be summarized as follows; 1. Stage-discharge relationship of the Drop-box weir was ?? at stage gaging point G-1. 2. The stage-discharge relationship at the stage gaing point G-1 appeared to have little effect with different approach angles. With different stream slopes, the relationship was one curve at discharges up to about 4㎥/s. On the whole the stream slope change appeared to influlence slightly to the stage-discharge relationship. 3. The maximum probable sediment accumulation estimated using the movable bed model test was 1.2~1.5 meters high meausred at 1.8 meters upstream from the weir head wall. This sediment accumulation showed little effect on a reliability of the stage-discharge relationship at the stage gaging point G-1. 4. The stage gaging point G-2 selected to supplement the limitations of the stage gaging point G-1 showed a straight lime stage-discharge relationship. This G-2 was generally safe against the approach angles, stream slope changes and sediment deposition at weir upstream. It can therefore be recommended that the gaging point be set up at G-2. 5. The greatest storm for a single event during the period of study was only 75mm. In the future it recommended that the stage-discharge relationship for the weir under study must be newly tested at high flow rates created by the greater storms. 6. From the results of the laboratory experiment and the observed operation of the drop box attached to the weir, it can be conclude that the Sangrim Drop-box weir is acceptable and representative of field weirs for other hydrologic studies in Korea.

畓에서의 有效雨量에 關한 硏究

金成俊,朴承禹,張秉郁,權純國,鄭夏禹 서울大學校 農科大學 1986 서울대농학연구지 Vol.11 No.1

In this study, a daily water balance model for effective rainfall in paddy fields is descrived, and compares the results with field data. The model was used to simulate seasonal effective rainfall for ideal plots with different irrigation scheduling. The followings are a summary of this study results: 1. Effective rainfall during irrigation season of paddy fields in 1985 ranged from 172.3mm at 4cm ridge to 206.7mm at 6cm ridge. They were 63.1% and 75.7% of total precipitation during that span, respectively. The water balance model simulated that 60.5% and 69.5% precipitation may be considered to be effective rainfall. 2. Daily rainfall appears to be important to the ratios of effective rainfall to the total. 3. Measured and estimated effective rainfall had a high correlation. R=0.9805

우리나라 중부지방의 시설원에 토양 및 지하수 환경

김진호,이종식,김원일,정구복,윤순강,정연태,권순국 한국환경농학회 2002 한국환경농학회지 Vol.21 No.2

연구대상 시설재배지 토양의 물리성은 대부분이 모래의 비율이 높은 sandy loam이나 loam으로 투수성이 양호할 것으로 판단되나, P2나 S1에서는 미사의 비율이 높은 미사 loam으로 투수성 및 통기성이 상대적으로 낮은 것으로 판단된다. 토양의 화학성은 EC의 경우 표토의 대부분이 기준치에 도달하거나, 초과하는 경향이었고, 심토의 경우는 기준치 이하로 조사되었다. 또한 유기물 함량은 적정수준 2~3%보다 조사 대상 지점의 대부분에서 상회하였고, 심토의 일부분도 이 수준을 넘는 곳도 있었다. 조사 대상 지역의 수질 특성 중 시설재배지 지하수의 가장 중요한 염류 지표인 EC는 연평균 0.48 dS/m로 농업용수로서 작물에 미치는 영향은 없는 것으로 판단되나, 수질오염지표인 질산성 질소의 경우 19.1 mg/L 로 농업용수 수질 기준인 20 mg/L에 근접한 수준을 나타내었다. 특히 조사 대상 지점의 36.4%가 수질 기준을 초과하는 것으로 나타났다. 지하수중의 이온의 양과 영양염류의 양을 간접적으로 나타내는 전기전도도인 EC는 양이온인 경우 Mg^(2+), Ca^(2+), Na^+, K^+와 정의상관이 있었으며, 특히 2가 양이온인 Mg^(2+)와 Ca^(2+)간에는 고도의 정의상관을 보이고 있었다. 또한 EC와 음이온간에는 NO_3^-, Cl^-, SO_4^(2-), PO_4^(2-)와 상관을 보이고 있었다. 지하수의 오염지표인 NO_3-N의 경우에는 COD를 제외한 모든 이온들과 상관을 보이고 있었다. 특히 SO_4^(2-), Cl^-, Na^+, Ca^(2+), Mg^(2+)와는 고도의 정의 상관을 보여주고 있다. 이는 NO_3-N는 EC와 함께 지하수오염의 중요한 지표중의 하나임을 보여주고 있다. The objective of this study was to know the qualities of soil and shallow groundwater in plastic film house fields around Central Part of Korea. The study was conducted at 11 sites in Suweon, Hwasung, Pyungtaek, Yongin, and Chuncheon through May to August in 1999. Soil textures of plastic films house were mainly sandy loam or loam. Electric conductivity and organic matter content of surface soils mostly exceeded the critical levels for crop production. Average concentration of N0_3-N in the shallow groundwater was 19.1 mg/L, and it reached almost the limiting level of agricultural groundwater quality (20 mg/L). Moreover about 36% of survey sites exceeded the limiting level of agricultural groundwater quality. Sulfate concentrations also at some sites exceeded agricultural groundwater quality limit level (50 mg/L). Nitrate-N, one of the most important factors in the groundwater quality, had positive correlations with other ions in groundwater.

농업용수 수질기준의 문제점 및 개선대책 : 외국사례와의 비교를 통해

김진호,이종식,정구복,윤순강,고문환,심재천,권순국 한국국제농업개발학회 2003 韓國國際農業開發學會誌 Vol.15 No.3

우리나라 농업용수 수질기준과 다른 국가 또는 농업관련 국제기구의 수질기준에 대한 비교분석을 통해 우리나라 농업용수 수질기준의 문제점 도출과 해결방안을 모색코자 본 연구를 수행하게 되었으며, 그 결과를 요약하면 다음과 같다. 1. 우리나라 농업용수 수질기준은 관개용수 수질기준이 아니고, 수원보호측면의 수질기준이라 할 수 있다. 2. 우리나라 수질기준중 유기물지표가 하천과 호소에 따라 BOD와 COD로 이원화되어 있고, 특히 COD의 경우 산화제로 KMnO4를 사용함으로써 효과적인 유기물지표로 활용할 수 없는 실정이다. 농업용수로의 활용측면에서는 K₂Cr₂O_(7)을 이용한 COD를 기준으로 도입하는 것이 유기물 분해능 및 수중의 유기물지표로 활용하고 있는 국제적 데이터 일치를 위해서도 타당하다. 3. 우리나라 농업용수 수질기준은 캐나다와 FAO에서 제시하고 있는 염류에 대한 기준은 거의 없는 실정이다. 또한 양이온에 대한 기준도 없다. 염류의 기준이 모든 이온 존재의 가능성을 의미하므로, 실험치 및 외국문헌에 의한 1.0dS/m수준을 한계농도로 선정해야 한다. 4. FAO와 캐나다에서 사용하고 있는 축산용수에 대한 수질기준이 없다. 5. 관개용 농업용수가 농업(작물)에 미칠 수 있는 영향을 평가하기 위해서는 수원별로 수질기준이 다른 것이 큰 모순이다. 따라서 관계부처에서는 부처간의 이해를 떠난 수질기준을 설정해야 한다. 6. 우리나라 농업용수 수질기준의 모순점을 극복하기 위해서는 농업의 안전성확보측면 위해 관개용수 수질기준과 축산용수 수질기준을 조속히 제정해야 할 것이다. Present problems and possible solutions on the Water Quality Standards for Agriculture in Korea, were identified in the study. Because the Ministry of Environment made the laws and standards without consulting the agri-scientists, among others, the water quality standards formulated were not suitable standards of FAO, Japan, Canada, and the likes. The BOD and COD are the organic materials indicators. In case of rivers, BOD are set for the indicator. And at reservoirs. COD are set. Especially. COD was analysed using KMnO₄It is not suitable oxidizing agent for COD. Because the oxidic capacity is very low. So, in most developed country, K₂Cr₂O_(7) is usually used to analyze COD. And the salts and cations are not belonged to the Korean Water Quality Standards for Agriculture. The water quality standards for agriculture have big differences among lakes, rivers and groundwater. To apply different standards by resources to evaluate the relationship between water and crops is conflicting. So, to overcome the these problems, the suitable water quality standards for irrigation and livestock should be set.

Finite Element Numerical Analysis on Tidal Characteristic Changes due to Seadike Construction

Kwun, Soon-Kuk,Na, Jeong-Woo,Chang, Hyun-Jin The Korean Society of Agricultural Engineers 1997 韓國農工學會誌 : 전원과 자원 Vol.39 No.2

Abstract [] The prediction of changes in the tidal regime due to the sea dike closure in the Saemankum area was performed using the nonlinear finite element model, TIDE. Based upon an overall comparison of calibrated model results with available field data, the TIDE model behaves well and is good representation of the hydrodynamic of the Saemankum tidal project area. It is shown that the TIDE model does an excellent job of computing the changes of tidal characteristics resulting in sea dike closure in an estuary area.