• 한국농공학회지
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• 제28권3호
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• pp.69-78
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• 1986

This studies were established to find out the characteristics of frequency distributiom for the number of occurrence and magnitude, probable flood flows according to the return periods, design floods, and design frequency factors for the studying basins in relation to the risk levels which can be correlated with design return period and the life of structure in the non-annual exceedance series. Eight watersheds along Han, Geum, Nak Dong and Seom Jin river basin were selected as studying basins. The results were analyzed and summarized as follows. 1. Poisson distribution and Exponential distribution were tested as a good fitted distributions for the number of occurrence and magnitude for exceedance event, respectively,at selected watersheds along Han, Geum, Nak Dong and Seom Jin river basin. 2.Formulas for the probable flood flows and probable flood flows according to the return periods were derivated for the exponential distribution at the selected watersheds along Han, Geum, Nak Dong, and Seom Jin river basin. 3.Analysis for the risk of failure was connected return period with design life of structure in the non-annual exceedance series. 4.Empirical formulas for the design frequency factors were derivated from under the condition of the return periods identify with the life of structure in relation to the different risk levels in the non-annual exceedance series. 5.Design freguency factors were appeared to be increased in proportion to the return periods while those are in inverse proportion to the levels of the risk of failure. Numerical values for the design frequency factors for the non-annual exceedance series ware appeared generally higher than those of annual maximum series already published by the first report. 6. Design floods according to the different risk levels could be derivated by using of formulas of the design frequency factors for all studying watersheds in the nor-annual exceedance series.

• 한국농공학회지
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• 제35권3호
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• pp.100-116
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• 1993

It is experienced fact that unreasonable design criterion and unsitable operation management for the agricultural structures including reservoirs based on short terms data of monthly flows have been brought about not only loss of lives, but also enormous property damage. For the solution of this point at issue, this study was conducted to simulate long series of synthetic monthly flows by multi-season first order Markov model with selection of best fitting frequency distribution and to make a comparison of statistical parameters between observed and synthetic flows of six watersheds in Yeong San and Seom Jin river systems. The results obtained through this study can be summarized as follows. 1.Both Gamma and two parameter lognormal distribution were found to be suitable ones for monthly flows in all watersheds by Kolmogorov-Smirnov test while those distributions were judged to be unfitness in Nam Pyeong of Yeong San and Song Jeong and Ab Rog watersheds of Seom Jin river systems in the $\chi$$^2$ goodness of fit test. 2.Most of the arithmetic mean values for synthetic monthly flows simulated by Gamma distribution are much closer to the results of the observed data than those of two parameter lognomal distribution in the applied watersheds. 3.Fluctuation for the coefficient of variation derived by Gamma distribution was shown in general as better agreement with the results of the observed data than that of two parameter lognormal distribution in the applied watersheds both in Yeong San and Seom Jin river systems. Especially, coefficients of variation calculated by Gamma distribution are seemed to be much closer to those of the observed data during July and August. 4.It can be concluded that synthetic monthly flows simulated by Gamma distribution are seemed to be much closer to the observed data than those by two parameter lognormal distribution in the applied watersheds. 5.It is to be desired that multi-season first order Markov model based on Gamma distribution which is confirmed as a good fitting one in this study would be compared with Harmonic synthetic model as a continuation follows.

• 한국농공학회지
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• 제35권3호
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• pp.117-129
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• 1993

This study was conducted to get reasonable and abundant hydrological time series of monthly flows simulated by a best fitting stochastic simulation model for the establishment of rational design and the rationalization of management for agricultural hydraulic structures including reservoirs. Comparative analysis carried out for both statistical characteristics and synthetic monthly flows simulated by the multi-season first order Markov model based on Gamma distribution which is confirmed as good one in the first report of this study and by Harmonic synthetic model analyzed in this report for the six watersheds of Yeong San and Seom Jin river systems. 1.Arithmetic mean values of synthetic monthly flows simulated by Gamma distribution are much closer to the results of the observed data than those of Harmonic synthetic model in the applied watersheds. 2.In comparison with the coefficients of variation, index of fluctuation for monthly flows simulated by two kinds of synthetic models, those based on Gamma distribution are appeared closer to the observed data than those of Harmonic synthetic model both in Yeong San and Seom Jin river systems. 3.It was found that synthetic monthly flows based on Gamma distribution are considered to give better results than those of Harmonic synthetic model in the applied watersheds. 4.Continuation studies by comparison with other simulation techniques are to be desired for getting reasonable generation technique of synthetic monthly flows for the various river systems in Korea.

• 생태와환경
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• 제44권2호
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• pp.144-154
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• 2011

섬강의 어류 군집구조 및 멸종위기어종 꾸구리(Gobiobotia macrocephala)와 돌상어(G. brevibarba)의 서식현황을 알아보기 위하여 2010년에 10개 지점을 선정하여 계절별로 조사하였다. 총 출현한 어종은 10과 37종이었고, 우점종은 피라미(Zacco platypus, 36.2%), 아우점종은(13.2%)와 돌상어(12.2%), 그 다음으로 쉬리(Coreoleuciscus splendidus, 8.1%)와 밀어(Rhinogobius brunneus, 4.9%) 등의 순으로 우세하게 출현하였다. 출현종 중 한국고유종은 18종(48.6%)이였으며, 환경부 멸종위기종은 꾸구리와 돌상어 2종이 출현하였다. 지점별 출현한 어종을 근거로 유사도 분석을 한 결과 상류(St. 1~3)와 중류(St. 4~6), 하류(St. 7~10)로 잘 구분되었으며 하류로 갈수록 우점도 지수는 대체로 낮아지고, 다양도 지수와 종 풍부도 지수는 대체로 높아지는 경향을 보였다. 멸종위기 어종인 꾸구리는 섬강 하류의 자갈과 돌이 쌓인 여울에서 서식하였고, 돌상어는 전구간에 쌓인 여울지역에 비교적 높은 비율로 서식하고 있었다.

• 생태와환경
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• 제49권3호
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• pp.215-227
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• 2016

담수생태계에서 어류기생충의 종류와 감염경로는 다양하고, 중형 또는 고등동물을 숙주로 하여 생활환을 이어가기 때문에 매우 복잡하다. 그중에서 어류의 복강에 기생하는 충류를 대상으로 수행되었다. 본 연구는 2007년 2월부터 10월까지 섬강에서 생긴 피라미의 기생충에 관한 민원을 해결하고자 생태계의 감염특성을 조사하였다. 섬강에서 복강기생충이 관찰된 시기에 감천, 대포천, 양산천 및 율하천도 동일하게 조사하였다. 저서성대형무척추동물은 수서곤충류와 패류가 각각 90.4%, 7.7%로써 주종을 이루었다. 수서곤충류는 하루살이류 (46.8%)와 날도래류 (29.8%)가 대부분을 차지하였고, 패류는 복족류였다. 어류는 잉어과와 피라미 (Zacco platypus)가 각각 85.7%, 48.8%로써 가장 풍부하였다. 물새 조류는 흰뺨검둥오리 (Anas poecilorhyncha)와 쇠백로 (Egretta garzetta)가 높은 밀도로 우점하였다. 어류기생충은 복강에 주로 기생하는 편형동물문 조충류 Ligula intestinalis로써 분류 동정되었다. 10월에 섬강과 양산천에서 우점 서식한 피라미로부터 각각 1개체, 15개체 관찰되었다. 복강기생충의 감염률은 1.4~15.8% 범위였다. 수서생태계의 조사결과로부터 기생충-숙주 관계의 감염 생활사를 고찰하였다. 본 연구결과는 국내의 육수학적 관점에서 복강기생충의 생태를 이해하는 데 유용한 기초자료로써 활용되기를 기대한다.

• 한국환경생태학회:학술대회논문집
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• 한국환경생태학회 2009년 학술대회 논문집 2호
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• pp.177-181
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• 2009

• 한국환경보건학회지
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• 제31권4호
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• pp.235-240
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• 2005

The effects of municipal sewage treatment plants on the water quality and effluent loading were investigated. BOD removal rates from Wonju, Hoengseong, and Hongcheon municipal sewage treatment plants were $88.9\%,\;80.6\%,\;90.7\%$ and T-P removal rates were $47.3\%,\;56.5\%,\;71.6\%,$ respectively. Also, BOD effluent leading from WonJu, Hoengseong, and Hongcheon treatment plants were 1,520 kg/day, 75 kg/day, 55 kg/day and T-P effluent loading were 203.9 kg/day, 4.2 kg/day, 4.0 kg/day, respectively. In terms of water quality distribution by distance of flow, BOD of the Seom river rapidly rose from 1.6 mg/l to 4.0 mg/l and T-P rose from 0.034 mg/l to 0.321 mg/l. Also BOD of the Hongcheon river showed a slowly rise from 1.1 mg/l to 1.4 mg/l and T-P from 0.011 mg/l to 0.026 mg/l. In conclusion, the effects of municipal sewage treatment plants on the water quality proved that T-P was higher than BOD. Consequently, in order to improve water quality, it is necessary to adopt an advanced sewage treatment system like nutrient removal.

• 한국지반환경공학회 논문집
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• 제12권8호
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• pp.51-57
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• 2011

섬진강 하류지역은 1978년 이후 지속적인 하상 세굴로 인하여 염수 침입이 확대된 지역으로서, 본 연구에서는 지하댐 설치 시의 염수침입 차단 효과를 수치모델로서 평가하였다. 현재 섬진강 하류 지표수의 염소이온농도는 상류로 가면서 지수함수적으로 감소하며, 지하수내 농도는 지표수의 1/10 이내로 나타난다. 하구로부터 4.6km 지점에 암반 상부로부터 25m 높이의 지하댐을 설치하는 조건으로 FEM 모델인 FEFLOW를 수행한 결과, 지하댐 상류의 퇴적 작용으로 현재보다 충적층의 두께가 5m 정도 두꺼워진다면 하구로부터 25km 지점에서의 염소이온농도(0.25psu)가 하류로 약 3km 정도 이동하는 것으로 나타났다. 반면에, 지하댐 상류에 퇴적물이 쌓이지 않을 경우에는 지하댐 설치 효과가 미미한 것으로 해석되었다.

• 농촌계획
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• 제24권4호
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• pp.81-88
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• 2018

With the increase of the number of riverfront development projects an objective and systematized survey and assessment tool is required to understand and identify the characteristics and potentials of river environment for human uses. The purpose of this study was to develop an assessment system for the investigation and evaluation of the water-friendly environment and to examine its effectiveness by applying the system to the selected study sites. Literature reviews, expert consultation, and preliminary survey were conducted to select highly relevant indexes to evaluate water-friendliness in rivers and, as a result, an assessment system of ten items in four areas was established. The assessment system were applied to 139 reaches of six rivers including Bykgye Cheon, Seom River, Gap Cheon, Yudeng Cheon, Naesung Cheon, and Kumho River. The scores and grade of water-friendliness were calculated per rivers and reaches, and their differences were prominent according to urban river, rural river, mountainous area and city area. Bykgye Cheon and Naesung Cheon got high scores in visual quality and Kumho River and Gap Cheon in community needs and potential uses. The scores of each section in the same river can be used as a basic data for the selection of appropriate sites for the development of hydrophilic space. In addition, it is expected that identifying the characteristics of each river help establish an appropriate management plan for the river.

• Ecology and Resilient Infrastructure
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• 제7권4호
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• pp.238-247
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• 2020

본 연구의 목적은 최근 급격하게 증가하고 있는 하천내 식생의 발생원인을 분석하는 것이다. 이를 위해 1984년에서 2018년까지 35년 동안 19개 지점의 월강우량 변화를 분석하였고, 섬강, 청미천, 내성천 식생 발생 단면에서의 수위변화를 분석하였다. 그 결과 2012년 이후 4월 강우량은 30% 증가하였고, 5월에서 9월까지의 강우량은 최대 49% 감소한 것으로 나타났다. 강우량이 감소한 2012년에서 2018년 사이에 섬강, 청미천, 내성천에서 하천 전단면이 침수되는 시간이 급격하게 줄어들었는데 섬강은 2012년, 청미천은 2013년 이후 고수부지가 한 번도 물에 잠기지 않았다. 내성천에서도 2013년 이후 저수로 전체가 침수되는 시간이 급격하게 줄어들었고 2015년에는 한 번도 잠기지 않은 것으로 나타났다. 이와 같은 영향으로 침수가 되지 않은 부분에서 식생이 급격하게 발생하였고 시간 경과에 따라 정착한 것으로 판단된다. 하천 식생의 확대와 정착은 하천 통수능의 감소 뿐만아니라 육역화로 인한 수상 생태계 상실로 이어질 수 있기 때문에 이에 대한 대책의 수립이 필요하다.