초록 ▼

최종(연차)목표
◦수권경계면에서 물질순환 평가를 위한 수리생태학적 기법 개발 및 수리환경요소간 상호작용 규명
- 수리경계면에서의 상호작용을 규명하기 위한 수리생태학적 다중기법 개발
- 해저유출 지하수 특성 평가를 통한 지하수-해수 상호작용 규명
개발내용 및 결과
◦산악 소유역내 다양한 수문요소에 대한 안정동위원소 및 화학적인자의 시계열 조사 및 수문요소별 고해상도-추적자기반 MTT(평균통과시간)산정, 하상퇴적물내 온도 추적자 시계열자료를 이용한 시공간별 공극 속도 추정 및 seepage rate/mass

최종(연차)목표
◦수권경계면에서 물질순환 평가를 위한 수리생태학적 기법 개발 및 수리환경요소간 상호작용 규명
- 수리경계면에서의 상호작용을 규명하기 위한 수리생태학적 다중기법 개발
- 해저유출 지하수 특성 평가를 통한 지하수-해수 상호작용 규명
개발내용 및 결과
◦산악 소유역내 다양한 수문요소에 대한 안정동위원소 및 화학적인자의 시계열 조사 및 수문요소별 고해상도-추적자기반 MTT(평균통과시간)산정, 하상퇴적물내 온도 추적자 시계열자료를 이용한 시공간별 공극 속도 추정 및 seepage rate/mass flux 측정을 위한 장비 검증, 인위적 영향이 큰 하천변 충적대수층내 다중심도 관측시스템 구축, 자동 관측 수행 및 영양염류포함 수질 조사 및 하천변 지하수유동 및 영양염류거동 개념모형구축
◦화산암 해안지역 유인/무인원격열화상탐사,방사성추적자,현장조사,수치모사결과 기반 통합적 해저지하수유출량 정량화 기법 검증 및 무인항공기 활용 지하수유출량 평가 국제공동연구 수행, 서해안 SGD 정량화를 위한 해수, 지하수, 하천수의 방사성추적자 농도 조사 수행, 담수렌즈 및 경계면 두께 시계열 변화 자료 획득 및 상업화기반 구축
◦호수-지하수 경계대 질소변환 관련 수리학 및 생물지구화학적 인자데이터베이스 구축 및 담수계 질소 생지구화학적 변화 신규기작(anammox)규명, 습지 생태계에서 비소의 sequestration에 미치는 철과 황 역할과 산화환원 환경변화에 따른 식물-토양계 비소 화학종 특성을 위한 온실 메조코즘 실험 수행 및 거동 특성 평가
기대효과
◦지하수-지표수 상호작용을 고려한 유역규모에서 기후변화에 따른수자원 변동성 평가 및 국가 수자원 정책 활용
◦부영양화 방지, 오염물 총량 관리 체계 보완 등 지표수계 수질 관리의 효율성 증대에 기여
◦지하수유입 특성을 고려한 연안 해수 수질 관리 체계 구축에 활용
적용분야
◦지하수-지표수 상호작용을 고려한 국가 수자원 정책 수립기반자료
◦영양염류 등에 대한 유역규모 오염물 총량관리 기초 자료 확보
◦하천수, 연안 해수 등 지표수계 수질관리기술 및 방안 기반 구축

Abstract ▼

CFCs results of 7points located on alluvial layer near Nakdong river showed groundwater age in the aquifer is old with ages greater than 50, vertical age gradient were verified at each multi depth well. Since biodegradation can occur in anaerobic condition, groundwater age should be checked using SF

CFCs results of 7points located on alluvial layer near Nakdong river showed groundwater age in the aquifer is old with ages greater than 50, vertical age gradient were verified at each multi depth well. Since biodegradation can occur in anaerobic condition, groundwater age should be checked using SF₆, and ³H/³He. The stable isotopic composition of oxygen and hydrogen integrated precipitation, soil water, groundwater and surface water were performed for one year to determine significant evaluation technique of mean transit time and to estimate mean transit time (MTT) at a small forested mountainous catchment in Gyeryong mountain. Since the deuterium excess (d value) of precipitation showed large amplitude as 13.8 ‰ and adequate seasonal variation, the seasonal variation of d value was considered for adequate input function in the study area influenced by the Asian monsoon. Based on attenuated amplitude and phase lag time from input function, estimated MTTs of soil water by depth and MTTs of stream were distributed ranging from 51 to 269 days and 177 to 323 days, respectively. The MTTs of headwater stream showed high relationship with total hillslope area and the ratio of stream length to gradient, indicating that development of soil layer by topographic condition and base flow by fracutres in rocks have a significant influence on MTT distribution of headwater stream. The seasonal variation of the 7Be activities in air was monitored by a continuous sampling with a high volume air dust sampler and 7Be activities in precipitation were determined. The activity level of 7Be in air was ranged from 1.94 to 47.2 Bq/m3 and 7Be in the precipitation was separated using cation exchange resin and the monthly average activity level was ranged from 0.29 to 4.77 Bq/L.
Dilution gaging experiment in field was performed to obtain net flux, mass loss,Qloss,MIN, Qloss,MAX, Qgain,MIN, and Qgain,MAX between upper and lower reaches of the Youndgo-chen in cheongwon. According to result, mass loss is 8.158 kg and the Youndgo-chen is regarded as losing stream since net flux shows negative. Also, in order to estimate seepage velocities according to the method of Hatch et al. (2006) using temporally varying stream temperature with daily period and temperatures at different depths within streambed, heat transport simulation model was developed. When estimating seepage velocity using amplitude ratio, it is estimated that at less than 5.0×10-5 m/sec of seepage velocity errors occur more than 25% but more than 3.0×10-4m/sec of seepage velocity errors produce less than 10%. In addition, prior to application of the Hatch method, in order to eliminate various errors with different amplitudes or large trend component with long period, SSA(Singular Spectrum Analysis) program was developed to obtain temporally varying time series with only daily period. Temperature data at different depths within streambed are obtained from nine piezometers and the developed SSA program is applied at those to extract time series with only daily period and thus Hatch method is applied at the extracted time series to calculate seepage velocity. The result shows that periods when downward and upward movement occur are different depending on installation depths of piezometer 5,6, and 7. From September in 2014 to March in 2015, downward flow occurs in a depth of 28cm to 92cm and afterwards upward flow occurs there. However, in a depth of 19cm to 28cm, downward flow occurs from September in 2014 to June in 2015 and afterwards upward flow occurs there. Therefore, we can see that hyphoreic zone exists around a depth of 28cm during March to June in 2015.
In this study, a new method to get time series of water flux and chemical fluxes via SGD was proposed and tested in near-shore environment. The water flow across the interface between surface water and groundwater is determined by not only a constant representing leakage coefficient but also the head difference between groundwater and surface water. Because leakage coefficient (L/T) is typically not measurable in the field, the method proposed in this study uses only the head difference between groundwater and surface water for measuring the water flow across the interface. Results of field test in Bangdu bay, Jeju were presented for verification of the newly designed methodology.
Submarine groundwater discharge (SGD) is a widely recognized process that carries large amounts of groundwater and dissolved chemicals to the ocean. In this study, we reported SGD variations influencing a coastal system in Korea, based on multiple-methods combining aerial remote sensing technology, field survey, and numerical simulation. The aerial surveys clearly showed distinct low temperature signatures of SGD along the coasts of Jeju Island, revealing large groundwater inputs from the coastal aquifers to the ocean. Numerical simulation of coastal system and continuous Rn monitoring also confirms the significant influence of SGD on the near-shore coastal system. We also reported here a successful application of UAV-based aerial TIR mapping supplemented by ground-based field investigations to quantify SGD. Based on the plume area-SGD flux relation together with the time-series SST maps, we estimated that the SGD flux of the study site lies between 33,000 and 54,000 m3d-1.The total fluxes of nitrogen, phosphorous, and silica per unit length of shoreline were estimated to be 20–44, 1.0–2.0×10-1,and 32–60 mold-1m-1, respectively. Our observations highlight that UAV-TIR mapping can serve as a powerful tool for study of SGD and other coastal processes.
Microbial community responses to the changes in groundwater flux was investigated at a coastal beach site, Korea. We performed water chemistry analyses, 16S rRNA gene-based pyrosequencing, and statistical community analyses on coastal water samples. Pyrosequencing and statistical community analyses revealed a periodic shift in the microbial communities in the coastal waters as a function of tidal stage and SGD rates. Interestingly, the community structures in the samples collected at flood and ebb tide were markedly different, despite the similarities in their water chemistry. Groundwater simulation and canonical correspondence analyses suggest that groundwater discharging at higher velocities at ebb tide detaches and transports subsurface bacteria from the aquifer to the coastal water body, resulting in unmistakable increase in γ-Proteobacteria, including anoxic or anaerobic bacteria in the ebb tide samples.
A measuring system for determining radioactive tracers (Rn, Ra) in groundwater and seawater has been established in this project. Submarine groundwater discharge(SGD) could be quantified using the measuring system. Radon (Rn-222) in groundwater and sea water was measured by RAD7 which was developed for measuring radon in air. High resolution continuous radon monitoring system was developed for determining radon activity variations at the groundwater - surface water interface. Radium isotopes(Ra-223, Ra-224, Ra-226 and Ra-228) in water and sediment were measured using HPGe and RaDeCC system with Mn-fiber concentration method. Finally, the SGD quantification system could be applied at the Sogeun-port and Geunheung-bay in Taeahn peninsular in Korea.
A new method using a floating device to monitor the time series change of thefreshwater-saltwater interface is developed for the first time and applied to Handong-1 Sea water intrusion monitoring station with a fixed-depth pressure sensor. The floating device, named sea water intrusion monitoring (SWIM) probe, can move up and down along with the freshwater-saltwater interface movement because it has intermediate density between freshwater, about 1.0 kg/L, and saltwater of about 1.025 kg/L. Based on the 21-days time series data in August, 2013, it is found out that maximum amplitude of the freshwater level and the interface are damped down to 1.1m and 0.14m, respectively, compared to tide of which maximum amplitude was 2.6m. Lag times of the freshwater level and the interface compared to tide were calculated to be 80 minute and 195 minutes, respectively. The SWIM probe can be expanded to sea water intrusion warning system if it is combined with a wireless submersible distance measuring device and remote communication technology. A time series prediction ANN model was developed and validated using the time series monitoring data of the freshwater-salt water interface location obtained from the Handong-1 observatory, Jeju.The model can predict the groundwater level and interface level well with correlation coefficient of 0.9 and 0.7, respectively.
A collaborative research project was begun to investigate processes influencing nitrogen fluxes across the boundary between groundwater and surface-water. The research team includes scientists from the Korean Institute of Geological and Mineral Resources, the United States Geological Survey, and the Virginia Institute of Marine Science. The overarching objectives are to understand the processes influencing the fate of nitrate and ammonium during discharge from groundwater to surface-water, to understand the time-scales on which these processes operate, and to identify the controls on processes and their time-scales. The approach is to determine groundwater flow directions and to quantify rates; to characterize the distribution and concentrations of nitrogen species and related solutes and parameters; to determine the potential of sediments for effecting nitrogen transformations and to identify those processes; to quantify in situ rates of nitrogen-transformation processes; and to characterize the microbial components in the sediments that are related to nitrogen-transformation processes. This approach involves application of molecular tools to characterize microbial components capable of effecting nitrogen transformations, laboratory experimental studies to understand processes and their potential rates, field-scale experiments and characterization to quantify rates of nitrogen transformations, and reactive transport model simulations to test conceptual and quantitative process models. The major findings of this international collaborative project are as follows. Nitrate and ammonium enter the lake via groundwater discharge at the northwest and north end of the lake; nitrate exits the lake at the south end via lake water recharge coupled to nitrification. Locations where anoxic, nitrate-contaminated or ammonium-contaminated groundwater travel through sediments vary over the course of the year as groundwater flow drives changes in lake stage. Functional genes for denitrification and anammox are observed in sediments experiencing groundwater discharge, lake water recharge, and where flow is stagnant. Sediments below approximately 10 cm exhibit very low rates of nitrogen processing, primarily by anammox. Potential denitrification rates are minimal in sediments experiencing discharge of ammonium rather than nitrate-contaminated groundwater; otherwise activity is weakly coupled to chemical conditions in discharging groundwater. Lake-derived organic carbon in surficial sediments fuels vigorous microbial processing of nitrate where anaerobic, nitrate-contaminated groundwater discharges. Lake-derived nitrogen compounds and dissolved oxygen drive nitrification as lake water recharges. Vigorous microbial processing of nitrogen in surficial sediments is demonstrated by laboratory incubations, assays of functional genes, field-scale injections of nitrite into the sediments, and observations of significant decreases in nitrate concentrations in pore water in surficial sediments compared to deep sediments. The pattern of groundwater discharge is complex. Hydrologic conditions can change from active discharge only within a few meters of the shoreline to active discharge well out into the lake within 100 meters. Where pore water is apparently stagnant,biogeochemical conditions can evolve to methanogenic, microbial populations dominated by anaerobes can be observed, and diagenesis can lead to high (hundreds of micromoles per liter) concentrations of ammonium.
We investigated the effect of dissimilatory iron and sulfate reduction on As dynamics in the wetland rhizosphere and its bioaccumulation in plants via greenhouse mesocosms. Results showed that the high Fe and SO₄^2- treatment is most favorable for As sequestration in soils in the presence of wetland plant (Scirpus actus), probably because the biodegradable organic carbon released from the wetland rhizosphere facilitated the microbial reduction of Fe(III), SO₄^2- and As(V) to remove As by precipitation/coprecipitation. Over the concentration range studied, As retention in soil and accumulation in plant were mainly controlled by SO₄^2- rather than Fe levels. Compared with the low SO₄^2- treatments, As sequestered in soils increased by 1.5 times, As accumulated in plant roots increased by 30 times, but As accumulated in plant leaves decreased by 49% in the corresponding high SO₄^2- treatments. As speciation analysis in pore water indicated that 19% more dissolved As was reduced under high SO₄^2- than low SO₄^2-. More dissimilatory arsenate-respiring bacteria under high SO₄^2- were detected by quantitative PCR.
Surface water-groundwater interaction was investigated in terms of microbial community structure. As the study site one of water-curtain cultivation area was selected, since heavy groundwater pumping/extraction is carried out during the cold season for additional warming the green houses by the groundwater temperature higher than the surface (stream) water. Heavy groundwater pumping is supposed to induce decline of groundwater level and migration of the nearby or adjacent stream water to the aquifer, which in turn changes the aquifer condition in the geochemical view point and even microbial community structures at least short period. The results of diversity and abundance of bacterial community structures and dissimilatory sulfite reductase gene indicate that two groups between stream (surface) water and groundwater show less statistical similarity than expected. This presumably suggests that microbial migration is limited in the given geological matrix, (i.e., silty and clay aquifer), unlikely the dissolved materials such as chemical compounds and organic materials, which could induce activation of indigenous bacteria and biogeochemical reactions such as microbial redox reactions on Fe, sulfate, etc.
Based on groundwater depth and flow rates measured in stream water,groundwater used for water curtain cultivation in the study area would be supplied from Nosung stream near wells. Increasing number of wells, compared to those in 2010 and 2011, led to increase in the amount of groundwater consumption, resulting in losing stream in 2014. With measuring in the field, groundwater and stream water were collected in 2014. Plot of oxygen and hydrogen isotopic compositions indicated that of the groundwater studied, groundwater in Buin-ri was affected by the more evaporation,compared to those in Wangjeon-ri. The higher proportion of rice paddy in Buin-ri than in Wangjeon-ri characterized by water curtain cultivation driven the water isotopic composition enriched. Groundwater in the study area was classified according to variation of electron acceptors during the study period. High Fe²⁺ concentration represented that groundwater was under anaerobic condition. In addition, considering the fate of NO₃^- and SO₄^2- with Fe²⁺, groundwater would be under the system including complex redox reactions, for example, denitrification, Fe reduction, sulfate reduction. For this suggestion, it is desirable to study in more detail. Both NO₃- and SO₄^2- showed either increase or decrease in wells including the period when Fe²⁺ was not detected. In contrary, either Fe²⁺ or Mn²⁺ varied corresponding to SO₄^2- in wells that Fe²⁺ was always detected. These occurrences resulted from the different degree of linkage between ground and surface environment. We will determine carbon isotopic composition for dissolved inorganic carbon and dual isotopic composition for nitrate and sulfate of water samples to decipher hydrogeochemical processes occurring in groundwater

목차 Contents

• 표지 ... 1
• 제출문 ... 2
• 최종 보고서 요약서 ... 4
• 요약문 ... 5
• SUMMARY ... 13
• Contents ... 19
• 목차 ... 21
• 제1장 연구개발과제의 개요 ... 24
• 제1절 연구 배경 및 필요성 ... 26
• 1. 배경 ... 26
• 2. 필요성 ... 28
• 제2절 연구 목적 ... 30
• 1. 연구사업 최종 및 연차별 목표 ... 30
• 2. 연구사업 추진 방법, 전략 및 체계 ... 31
• 제3절 연구 범위 ... 38
• 1. 개발 대상 기술 개요 ... 38
• 2. 연차별 연구내용 및 범위 ... 47
• 제2장 국내외 기술개발 현황 ... 50
• 제1절 선행기술 조사 ... 52
• 1. 특허 조사 결과 및 차별성 ... 52
• 2. 논문조사 결과 및 차별성 ... 54
• 제2절 선행연구사업 수행 현황 ... 57
• 1. 국내 선행연구사업 조사 결과 ... 57
• 2. 선행연구사업과의 차별성 ... 58
• 3. 선진국 연구기관의 연구실 기술수준분석 결과 ... 59
• 제3장 연구개발 수행내용 및 결과 ... 60
• 제1절 수리생태학적 다중기법 개발 및 상호작용 규명 ... 62
• 1. 안정동위원소 기반 자연산림유역 물순환 평가 기법 개발 ... 62
• 2. 온도 자료 기반 지표수-지하수 상호작용 해석 기술 개발 ... 86
• 3. 지하수-지표수 경계대 물/물질 교환량 측정기술 개발 ... 119
• 제2절 해저유출지하수 평가 및 상호작용 규명 ... 127
• 1. 다중기법을 활용한 SGD 평가 기법 개발 ... 127
• 2. 방사성추적자 활용 SGD 정량화 기법 개발 ... 162
• 3. 해안지하수 담염수 경계면 변동 특성 연구 ... 185
• 제3절 생태계활용 오염저감 및 정화 특성화 ... 199
• 1. 지하수-호수 경계대 질소순환 평가 기법 개발 ... 199
• 2. 습지 지역 비소 거동 및 비소 축적 식물 생태 특성 ... 215
• 3. 수막재배지역 지하수-하천수 상호작용 평가 ... 230
• 제4장 목표달성도 및 관련분야에의 기여도 ... 252
• 제1절 목표 달성도 ... 254
• 1. 최종 연구목표의 달성도 ... 254
• 2. 연차(3차년도) 목표 달성도 ... 255
• 제2절 관련분야에의 기여도 ... 256
• 제5장 연구개발결과의 활용계획 ... 258
• 가. 정책적 측면 ... 260
• 나. 과학기술적 측면 ... 260
• 다. 국민생활과 사회수준 향상에의 기여 측면 ... 261
• 제6장 연구개발과정에서 수집한해외과학기술정보 ... 262
• 제1절 UNEP-DHI 연구사업 협력 ... 264
• 1.1. 서론 ... 264
• 1.2. 본론 및 방문활동 ... 264
• 1.3. 결론 및 건의사항 ... 267
• 제2절 USGS 국제공동연구 ... 269
• 1. USGS-KIGAM 공동연구활동 (2013년) ... 269
• 2. USGS-KIGAM 공동연구활동 (2014년) ... 273
• 3. USGS-KIGAM 미국 현장연구 활동 (2014년) ... 278
• 4. USGS-KIGAM 공동연구활동 (2015년) ... 284
• 제3절 Princeton University 국제공동연구 ... 288
• 1. Princeton University-KIGAM 공동연구활동 (2014년) ... 288
• 2. Princeton University-KIGAM 공동연구활동 (2015년) ... 291
• 제4절 IAEA 주관 삼중수소의 최근 연구동향 ... 295
• 1. 서론 ... 295
• 2. 본론 ... 295
• 3. 결론 ... 296
• 제5절 University of Hawaii 국제공동연구 (UAV 기반 SGD 유출탐지 현지 조사) ... 297
• 1. 서론 ... 297
• 2. 본론 ... 297
• 3. 결론 ... 301
• 제7장 참고문헌 ... 302
• 부록 2015 국제위탁과제 최종요약보고서 영문초록 ... 312
• 1. USGS 국제위탁 최종보고서 영문초록 ... 314
• 2. Princeton Univ. 국제위탁 최종보고서 영문초록 ... 316
• 끝페이지 ... 319