• 제목/요약/키워드: Dry river

검색결과 454건 처리시간 0.023초

유수소통을 통한 태화강 적조해결 방안 연구 (A Study on Taehwa River Red Tide Solution through Stream Flow)

  • 조홍제;윤성규
    • 한국습지학회지
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    • 제13권2호
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    • pp.363-375
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    • 2011
  • 최근 하수관거 매설과 하수종말처리장 등의 건설로 인해 도시하천의 수질이 크게 개선되고 있으나, 하 폐수 처리시설의 부족으로 하천으로 유입되는 다양한 오염물질은 수중생태계 교란과 적조를 발생시키고 있다. 울산 태화강의 하류부는 하폭이 크고 하상경사가 매우 완만한 감조하천으로써 갈 저수기에는 유속이 매우 느리게 된다. 게다가 약 1.2km 떨어져 있는 2개 교량의 전면기초로 된 교각보호공으로 인해 흐름이 정체되고 오염물질이 퇴적되어, 수년전부터 발생하고 있는 태화강 적조의 원인이 되거나 적조를 활성화 시키고 있다. 본 연구에서는 RMA2모형을 이용하여 두 교량의 교각을 독립기초로 개선하고 흐름을 소통시킬 수 있는 통수단면을 확보했을 때, 수리학적으로 개선될 수 있는 유속과 유량의 변화폭을 모의하였다. 그 결과 유속은 최대 약 103%, 유량은 최대 61% 증가하는 것으로 나타났다. 이는 적조를 직접 소멸시킬 수는 없으나 적조발생을 억제하거나 감소시킬 수 있으며, 오염물질의 퇴적을 막아 적조발생 원인을 근원적으로 제어할 수 있는 것으로 판단된다.

모래여과 및 오존처리에 의한 하천수 수질개선 효과 연구(1) - BOD, COD, SS 및 색도 제거 경향 고찰 (Improvement of River Water Quality By Combined Treatment of Sand Filtration and Ozonation(1) - Focusing on Reduction of BOD, COD, SS and Color)

  • 최창희;남궁규철;윤종우;이채영
    • 한국물환경학회지
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    • 제27권6호
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    • pp.813-821
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    • 2011
  • While various aspects affect river water quality, reduction of water flow rate during dry seasons is one of the most significant factors causing severe water pollution in river water environment. The aim of this study is to investigate the feasibility of applying a physicochemical method (sand filtration + ozonation) for improving river water quality within a short period. The parameters analyzed and assessed were $COD_{cr}$, BOD, SS and color. The source river water had a severe pollution level showing COD 8.8~17.2 mg/L (ave. 11.9 mg/L), BOD 4.8~13.3 mg/L (ave. 8.3 mg/L), SS 9.0~22.1 mg/L (ave. 12.8 mg/L) and color 34.4~77.1 degree (ave. 56.5 degree) during the experimental periods. The variation trends showed a relatively low correlation between BOD and COD and between color and COD, while SS showed very low correlation with other parameters. The combined process of sand filtration and ozonation showed averaged removal efficiency of COD 37.2%, BOD 48.4%, SS 60.1% and colority 45.1%, respectively. The marked change of BOD level from 8.3 mg/L to 4.3 mg/L under the experimental conditions in this study implied the improvement of class V to class III set by the river water quality standard in Korea.

Long Term Monitoring of Storm Surface Runoff from Urban Pavement Road in Korea

  • Lee, C.S.;Seo, G.T.;Lee, J.H.;Yoon, Y.S.;You, J.J.;Sin, C.K.
    • Environmental Engineering Research
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    • 제13권4호
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    • pp.184-191
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    • 2008
  • Long term monitoring was conducted to investigate a surface runoff of pollution from urban highway. The monitoring data was collected for 18 rainfall events and was used to correlate pollution load to various parameters, such as rainfall intensity, antecedent dry days and total discharge flow. Runoff coefficient and seasonal variation were also evaluated. The mean runoff coefficient of the highway was 0.823(range; $0.4687{\sim}0.9884$), and wash-off ratio for $COD_{Mn}$ and SS loads was 72.6% and 64.3%, respectively. For the initial rainfall event, the runoff EMC of $COD_{Mn}$ was high in summer and the EMC of SS was high in autumn season. However the seasonal variation of T-N and T-P was not significant. The discharged $COD_{Mn}$-EMC was $147.6\;mg/L{\sim}9.0\;mg/L$ on the generated $COD_{Mn}$-EMC of $98.8\;mg/L{\sim}8.9\;mg/L$. While the generated EMC of SS was in $285.7\;mg/L{\sim}20.0\;mg/L$ and its discharged EMC was in $190.4\;mg/L{\sim}8.0\;mg/L$. EMC of pollutants was not directly related to the first flush rainfall intensity and the antecedent dry days. But the correlation was relatively high between EMC and cumulative runoff flow volume. The trend of EMC was reduced with the cumulative runoff flow volume.

강우기 및 평수기의 팔당호 유기물 수지산정 (Organic Carbon Budget during Rainy and Dry Period in Paldang Reservoir)

  • 이유희;정동일;박혜경
    • 생태와환경
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    • 제37권3호통권108호
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    • pp.272-281
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    • 2004
  • 팔당호의 유기물 수지 산정을 위해 팔당호내 일차생산력을 측정하고 유입하천의 유입유기물량 및 방류유기물량을 측정하여 유기물부하에서 내부생성유기물의 기여도를 평가하였다. 식물플랑크톤에 의한 일차생산력은 지점과 시기에 따라 큰 차이를 보여 3회 조사결과 $101{\sim}2701\;mgC\;m^{-2}day{-1}$의 범위로 나타났으며, 체류시간이 길고, 수체내 클로로필 a농도가 높았던 6월에 모든 지점에서 높은 생산력을 보였다. 빈번한 강우로 체류시간이 짧고 조류현존량이 적었던 4월과 8월의 조사에서는 총 유기물유입량에서 내부생성유기물량은 약 7%를 차지하였고 이중 식물플랑크톤에 의한 내부생산기여도는 약 5%로 매우 낮았다. 그러나 조사일 전후로 강우가 없어 수체가 안정되었고 외부유입유기물량이 적었던 6월 조사에서는 식물플랑크톤에 의한 내부생산 기여도가 29.0%를 보였다.

Effect of climate change and sea level rise on taking water of South Thai Binhirrigation system in Vietnam

  • Nguyen, Thu Hien;Nguyen, Canh Thai
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2015년도 학술발표회
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    • pp.222-222
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    • 2015
  • Vietnam is one of the most vulnarable countries affected by climate change and sea level rise. One of the consequences of climate change and sea level rise is the increase of salinity intrusion into the rivers which is challenging to irrigation systems in coastal areas. This indicates the necessary to study the ability of taking water through sluice gates of irrigation systems in coastal zones, especially in the dry season with the effects of climate change and sea level rise in the future. In this paper, Nam Thai Binh irrigation system is selected as a case study. The irrigation system is one of 22 biggest irrigation systems of the Red River delta in Vietnam located in coastal region. The computed duration is selected in dry season to irrigate for Winter-Spring crops. The irrigation water for the study area is taken from different sluice gates along the Red River and the Tra Ly River. In this paper, MIKE-11 model was applied to assess the ability of taking water for irrigation of the study area in current situation and in the context of climate change and sea level rise senario in 2050 (under the medium emissions scenario (B2) published by the Ministry of Natural Resources and Environment of Vietnam published in 2012) with different condition of water availability. The operation of the gates depends on the water levels and sanility conditions. The sanility and water level at different water intake gates of Nam Thai Binh irrigation system were simulated with different senarios with and without climate change and sea level rise. The result shows that, under climate change and sea water level rise, some gates can take more water but some can not take water because of salinity excess and the total water taking from the different gates along the rivers decrease while the water demand is increase. The study indicates the necessary to study quantitatively some recommended solutions in the study area particularly and in coastal region generally in Vietnam to ensure water demand for irrigation and other purposes in the context of climate change and sea level rise in the future.

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화학적 수문곡선 분리기법을 이용한 낙동강 최상류 유역 기저유출량 산정 (Base Flow Estimation in Uppermost Nakdong River Watersheds Using Chemical Hydrological Curve Separation Technique)

  • 김령은;이옥정;최정현;원정은;김상단
    • 한국물환경학회지
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    • 제36권6호
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    • pp.489-499
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    • 2020
  • Effective science-based management of the basin water resources requires an understanding of the characteristics of the streams, such as the baseflow discharge. In this study, the base flow was estimated in the two watersheds with the least artificial factors among the Nakdong River watersheds, as determined using the chemical hydrograph separation technique. The 16-year (2004-2019) discontinuous observed stream flow and electrical conductivity data in the Total Maximum Daily Load (TMDL) monitoring network were extended to continuous daily data using the TANK model and the 7-parameter log-linear model combined with the minimum variance unbiased estimator. The annual base flows at the upper Namgang Dam basin and the upper Nakdong River basin were both analyzed to be about 56% of the total annual flow. The monthly base flow ratio showed a high monthly deviation, as it was found to be higher than 0.9 in the dry season and about 0.46 in the rainy season. This is in line with the prevailing common sense notion that in winter, most of the stream flow is base flow, due to the characteristics of the dry season winter in Korea. It is expected that the chemical-based hydrological separation technique involving TANK and the 7-parameter log-linear models used in this study can help quantify the base flow required for systematic watershed water environment management.

Fecal sterol을 이용한 울산만과 주변해역 퇴적물내 하수기인 유기물 평가 (Evaluation of sewage-derived organic matter using fecal sterols in the sediments from Ulsan Bay and adjacent areas)

  • 최민규;최희구;김상수;문효방
    • 한국환경과학회지
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    • 제14권1호
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    • pp.23-32
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    • 2005
  • Surface sediments (0$\~$4 cm) were sampled at 40 stations from Ulsan Bay and its adjacent areas of Korea, to evaluate the contamination by sewage-derived organic matters using fecal sterols. Some sterols were quantified by gas chromatography coupled to mass spectrometry (GC/MS). Total concentrations of eight sterols (co­prostanol, cholesterol, cholestanol, epicholestanol, epicoprostanol, ${\beta}-sitosterol,$ brassicasterol, and stigmasterol) in the sediments from Ulsan Bay and its vicinity varied from 929 to 23,444 ng/g dry weight. The most predom­inant sterols were cholesterol and coprostanol, accounting for $33\~72{\%}$ of total sterols. The concentration of coprostanol known as the indicator of human feces ranged from 141 to 8,257 ng/g dry weight. In particular, the coprostanol concentrations in the sediments from Jansaengpo Harbor and Taehwa River exceeded the value of 1,000 ng/g dry weight, suggesting that these areas could be considered as the hot-spot zones by municipal sewage contamination. Some molecular indices and multivariate data analysis were used to assess the origin of these sterols in the sediments. Results showed that the major routes of sewage contamination in Ulsan Bay and its vicinity were the input through Jansaengpo Harbor and Taehwa River.

건기 실측간격, 강우인자에 따른 탱크모형 매개변수 추정 (Parameter Estimation of Tank Model by Data Interval and Rainfall Factors for Dry Season)

  • 박재일;백천우;전환돈;김중훈
    • 한국물환경학회지
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    • 제22권5호
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    • pp.856-864
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    • 2006
  • For estimating the minimum discharge to maintain a river, low flow analysis is required and long term runoff records are needed for the analysis. However, runoff data should be estimated to run a hydrologic model for ungaged river basin. For the reason, parameter estimation is crucial to simulate rainfall-runoff events for those basins using Tank model. In this study, only runoff data recorded for dry season are used for parameter estimation, which is different to other methods based on runoff data recorded for wet and dry seasons. The Harmony Search algorithm is used to determine the optimum parameters for Tank model. The coefficient of determination ($R^2$) is served as the objective function in the Harmony Search. In cases that recorded data are insufficient, the recording interval is changed and Empirical CDF is adopted to analyze the estimated parameters. The suggested method is applied to Yongdam dam, Soyanggang dam, Chungju dam and Seomjingang dam basins. As results, the higher $R^2s$ are obtained when the shorter recording interval, the better recorded data quality, and the more rainfall events recorded along with certain rainfall amount is. Moreover, when the total rainfall is higher than the certain amount, $R^2$ is high. Considering the facts found from this study for the low flow analysis, it is possible to estimate the parameters for Tank model properly with the desired confidence level.

우리나라 과거 가뭄사상의 정량적 특성 분석 -강수량의 이상치 분석을 중심으로- (Quantitative characterization of historical drought events in Korea -focusing on outlier analysis of precipitation-)

  • 장호원;조형원;김태웅;이주헌
    • 한국수자원학회논문집
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    • 제49권2호
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    • pp.145-153
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    • 2016
  • 본 연구에서는 우리나라에서 발생했던 과거 가뭄사상을 정량적으로 평가하기 위해 우리나라의 59개 기상관측소의 월강수량 자료를 이용하여 연강수량 및 계절별(봄철) 강수량에 대한 이상치($-1{\sigma}$)를 분석하였다. 연강수량을 통해 이상치 발생 빈도를 구하여 그 중 가장 유역별로 과우해($-1{\sigma}$) 발생빈도가 높은 이천, 거창, 정읍, 순천, 장흥 관측소를 선정하여 이상치를 분석한 결과 1988, 1994년이 동일하게 심한 과우해로 나타났다. 전체 이상치 기간 분석결과와 봄철 이상치 분석결과를 통해 2001년 가뭄은 심한 과우해로 분류되지는 않았지만 주로 섬진강 및 영산강 유역을 중심으로 심한 봄 가뭄이 발생하였으며, 농업용수 부족으로 인한 농작물 피해를 발생시킨 대표적인 농업적 가뭄연도로 분석되었다. 반면에 1981-1982년 및 1994-1995년과 같이 2년 이상 지속된 전국적 장기가뭄은 국가적으로 큰 가뭄피해를 야기하였다.

간이변환 수질예측모델에 의한 영일만 내부생산성 평가 (Numerical Simulation of water quality by ${\Delta}COD$ method for Inner Productivity Estimation of Yeong-Il Bay)

  • 윤한삼;류청로;이인철;김헌태
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2003년도 춘계학술대회 논문집
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    • pp.99-104
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    • 2003
  • This study investigated the yearly variation of pollutant loads outflowing from six watershed of Yeong-il Bay and compared the relationship of pollutant load and water quality, and estimated the Inner productivity of Yeong-Il Bay by using ${\Delta}COD$ method which analysis nonlinear process of water quality. As the estimated results for the pollutant loads of Yeong-Il Bay, total COD load outflowing from Hyeong-san river in flood season(summer) of 2001 year was 2275.0 kg/hr and in dry(low water) season(winter) 852.8 kg/hr, respectively. Load quantity in flood season was about 2.67 times than that in dry season. And as the calculated results of the net-flux of water for seven divisions, it showed that the net-flux of water increased for the divisions of the north coast and inner sea of Yeong-Il Bay but decreased for the south coast. On the contrary, for the cases which water quantity increase from land, the net-flux of water in estuary front of Hyeong-san river decreased but outflowing quantity of that though division of the south coast of Homi-got increased. Finally, this study compared the Inner productions for flood and dry season of Yeong-il Bay by using ${\Delta}COD$ method.

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