• The Korean Journal of Ecology
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• 제13권4호
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• pp.297-309
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• 1990

The distribution of aquatic macrophytes in TanChon basin, a stream of the Han River, were investigated in terms of environmental gradient from June 1989 to March 1990. In the basin, 12 species of aquatic macrophytes were listed and four communities of Potamogeton crispus community. $P. octandrus$ community, $Hydrilla verticillata$ community and $Vallisneria$ asiatica community were recongized by character species. $P. crispus, P. octandrus$ and $V. asiatica$ were found in rapids while $H. verticillata , Ceratophyllum demersum$ and $Trapa japonica$ were done in pools. The depth of sediment $TanCh\u{o}n$ was showed as a exponential function of water velocity, Bd=exp (-K Wv). The values of Biochemical Oxygen Demand(BOD), Chemical Oxygen Demand(COD) and Suspendid Solid(SS) were recorded as range of 3.2~121.0mg/1, 4.2~54.5mg/1 and 4.1~114.0mg/1, respectively. And the linear positive correlation between BOD(X) and COD(Y) were expressed as Y=3.904+0.4308 X with $R^2$=0.9808 and also the correlation between BOD value(X) and SS value(Y) were done as Y=5.333+0.9606X with $R^2$=0.9700. In two dimensional analysis of BOD and water velocity, their clusters were showed similar types matching to communities classified by character species. However, no aquatic macrophyes were found at the site with BOD$\geq$50mg/l or DO$\leq$0.2mg/l.

• Journal of Species Research
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• 제8권4호
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• pp.395-406
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• 2019

The aim of this study was to compile a species list of endemic water beetles of Mongolia and determine their distribution patterns. A total of 1,179 individuals of endemic water beetles were collected from nine different sub-basins (123 sample points) throughout the country. Currently, 21 endemic and sub-endemic species have been recorded in Mongolia. Eight of these species were strictly endemic. The endemic and sub-endemic species were found only among four families: Dytiscidae (10 out 99 spp.), Gyrinidae (1 out 7 spp.), Helophoridae (5 out 16 spp.), and Hydraenidae (5 out 13 spp.). The rate of endemism was higher in Hydraenidae than other families (38.4%). Endemic beetle fauna was most similar between the Onon and Kherlen River Basins (80%). Helophorus parajacutus Angus, 1970 was common in five sub-basins, but Agabus kaszabi $Gu{\acute{e}}orguiev$, 1972, Gyrinus sugunurensis Nilsson, 2001 and Ochthebius mongolicus Janssens, 1967 were recorded from only one sub-basin. In terms of sub-endemic species, Mongolia was mostly similar to the fauna of Eastern Siberia, Russia (73.7%) than other neighboring regions. Due to Mongolia's vast territory and different natural zones, endemism was exceptionally low (12.4%), but these data provide baseline information of endemic and rare species for their further conservation.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2021년도 학술발표회
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• pp.127-127
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• 2021

In order to estimate parameter uncertainty of hydrological models, the consideration of the likelihood functions which provide reliable parameters of model is necessary. In this study, the Bayesian Markov Chain Monte Carlo (MCMC) method with informal likelihood functions is used to analyze the uncertainty of parameters of the SURR model for estimating the hourly streamflow of Gunnam station of Imjin basin, Korea. Three events were used to calibrate and one event was used to validate the posterior distributions of parameters. Moreover, the performance of four informal likelihood functions (Nash-Sutcliffe efficiency, Normalized absolute error, Index of agreement, and Chiew-McMahon efficiency) on uncertainty of parameter is assessed. The indicators used to assess the uncertainty of the streamflow simulation were P-factor (percentage of observed streamflow included in the uncertainty interval) and R-factor (the average width of the uncertainty interval). The results showed that the sensitivities of parameters strongly depend on the likelihood functions and vary for different likelihood functions. The uncertainty bounds illustrated the slight differences from various likelihood functions. This study confirms the importance of the likelihood function selection in the application of Bayesian MCMC to the uncertainty assessment of the SURR model.

• 한국습지학회지
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• 제11권3호
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• pp.161-169
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• 2009

도시 지역의 강우-유출 과정은 자연유역과 비교하여 보다 복잡한 형태를 지니고 있다. 도심의 확장과 개발로 인해 유역의 특성들이 변화하고, 이로 인해 유출 모형의 적용 또한 어렵다. 본 연구에서는 전주의 대표적인 도시하천인 조경천 유역을 대상으로 도시화의 진행에 따른 수문환경의 변화와 강우-유출 형태의 변화를 분석하였다. 도시화 정도에 따라 도시화가 진행되기 전인 자연유역기(1924), 전북대학교 조성기(1963), 주거단지 조성기(1986), 도시화 완료기(1995)로 단계를 구분하고, 각 단계별 유역특성자료와 불투수면적 등의 입력자료를 기반으로 SWMM 모형을 이용하여 유출을 분석하였다. 단계별 배수계통도에 의하면, 유로연장, 조도계수, 지표면 저류계수는 감소하였고, 토지이용 상태는 투수면적이 97.7%에서 42%로 감소하였고, 불투수 면적은 0.6%에서 34.0%로 증가하였다. 도달시간은 90분에서 37분으로 감소하였고, 첨두유량은 $4.37m^3/s$에서 $111.13m^3/s$로 증가 하였으며, 유출률은 0.8%에서 68%로 증가하였다.

• 농촌의학ㆍ지역보건
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• 제26권2호
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• pp.1-6
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• 2001

2001년 7월에서 10월 동안 전북 지역 4개강- 금강, 만경강, 동진강, 섬진강에서 민물어류를 채집하여 간흡충 피낭유충 감염상을 조사하였다. 금강 에서는 몰개와 참붕어에서 간흡충 피낭유충이 어체 1g당 평균 12개와, 26개가 검출되었다. 만경강에서는 몰개에서만 4개가 검출되었다. 섬진강에서는 돌고기에서만 7개 검출되었으며, 동진강에서는 검출되지 않았다. 섬진강 유역의 순창 지역 주민의 대변 검사 결과 간흡충 충란 양성률은 1999년에 8.9%, 2000년에 6.8%로 조사되었다. 이상의 결과로 전북지역의 4개강에 서식하는 참붕어, 몰개, 돌고기 등에서 간흡충의 피낭유충이 다수 감염되어 있음을 확인하였으며 이 지역 주민에서 이들 민물어류의 생식에 의한 간흡충 감염이 만연되고 있음을 알 수 있었다.

• Advances in environmental research
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• 제7권2호
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• pp.87-107
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• 2018

Water quality monitoring network needs periodic evaluations based on environmental demands and financial constraints. We used a genetic algorithm to optimize the existing water quality monitoring stations on the Sefid-Rud River, which is located in the North of Iran. Our objective was to optimize the existing stations for drinking and irrigation purposes, separately. The technique includes two stages called data preparation and the optimization. On the data preparation stage, first the basin was divided into four sections and each section was consisted of some stations. Then, the score of each station was computed using the data provided by the water Research Institute of the Ministry of energy. After that, we applied a weighting method by providing questionnaires to ask the experts to define the significance of each parameter. In the next step, according to the scores, stations were prioritized cumulatively. Finally, the genetic algorithm was applied to identify the best combination. The results indicated that out of 21 existing monitoring stations, 14 stations should remain in the network for both irrigation and drinking purposes. The results also had a good compliance with the previous studies which used dynamic programming as the optimization technique.

• 한국물환경학회지
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• 제31권6호
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• pp.700-714
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• 2015

The characteristic of the water quality and pollutant discharge was analyzed at the units watershed of the total amount management in Han-river basin, and after classified in a similar area by multivariate statistical analysis, the main trend such as the water quality trend and pollutant discharge characteristic were analyzed. As a result of this study, the density of the pollutant at the unit watershed is not necessarily identified as discharge density, and the primary management watershed and targeted substances were analyzed depending on the operating status of the environmental infrastructure in watershed and the main pollution factor and discharge path per pollutants. As a result of cluster analysis, watersheds were classified into four groups according to discharge characteristics. It will be used when selecting target area of primary management that is appropriate to the characteristics of each river and establishing efficient water quality improvement plans.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2020년도 학술발표회
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• pp.118-118
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• 2020

This study investigates the change of flow characteristics over 10 Asian river basins in the past 30 years (1976-2005). The variation is estimated from The Soil and Water Assessment Tool (SWAT) model outputs based on reanalysis data which was bias-corrected for Asian monsoon reagion. The model was firstly calibrated and validated using observed data for daily streamflow. Four statistical criteria were applied to evaluate the model performance, including Coefficient of determination (R2), Nash - Sutcliffe model efficiency coeffi cient (NSE), Root mean square error-observations standard deviation ratio (RSR), and Percentage Bias (PBIAS). Then parameters of the model were applied for the historical period 1976-2005. The estimates show a temporal non-considerable increasing rate of daily streamflow in most of the basins over the past 30 years. The difference of monthly discharge becomes more significant during the months in the wet season (June to September) in all basins. The seasonal runoff shows significant difference in Summer and Autumn, when the rainfall intensity is higher. The line showing averaged runoff/rainfall ratio in all basins is sharp, presenting high variation of seasonal runoff/rainfall ratio from season to season.

• 물과 미래
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• 제13권1호
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• pp.39-48
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• 1980

우리나라 5대 하천유역 즉 한강, 낙동강, 금강, 영산강 및 섬진강에 대한 지역최대일 강우량의 실측기록을 써서 지역강우빈도 분석을 실시한바 분석방법으로는 다섯가지 방법을 활용하여 비교 검토하였다. 지역강우에 대한 빈도분석은 많이 이루어졌으나 지역강우에 대한 연구는 찾아 볼 수 없었기 때문에 이 성과를 쓴다면 홍수해석에 도움을 줄 수 있겠다 하겠다. 본 연구에서 제시한 강우량의 빈도별 산정식을 쓴다면 수문관측 기록이 나와 있지 않은 기타 지역에도 지역확률 강우량을 산정 할 수 있다.

• 한국물환경학회지
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• 제28권6호
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• pp.786-795
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• 2012

Water quality management should be focused on the pollution concentrated area so that the improvement of water quality can be achieved effectively for the management of Total Maximum Daily Loads (TMDLs). It is necessary to consider discharge characteristics in the TMDL plan. This study analysed discharge characteristics such as pollution generation and discharge load density, and reduction potential by each unit watershed, and categorized the unit watershed into four groups according to its discharge load characteristics. This analysis can be used as helpful information for the prioritization of pollution reduction area and selection of pollution reduction measures in the development of TMDL plans.