• The Korean Journal of Ecology
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• 제21권5_1호
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• pp.409-418
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• 1998

A molel study was conducted to determine the optimal sample size for the analysis of the aquatic insect community in a stream reach of the Pangtae Creek, Kangwon-do in October 1995 and may 1996. The results showed that the required minimum sample size varied and depended on the purposes of the community analysis. Acoording to the Species: Area Curve method, at least 16 Surber samplings ($30{\times}30cm$) were required in a stream reach in each spring and fall survey. The species diversity index did not vary significantly as the sample size increased. Based on the coefficient of variation analysis, the minimum sample sizes of 10 were required in order to compare seasonal differences of the community in the study area. Considering the static community structure of aquatic insects, including both species numbers and individual numbers of aquatic insects, 11 and 7 samplings were optimal sizes for the fall and spring survey, respectively. We concluded that 12 Surber samplings from 3 riffle-pool sequences (4 samplings at each riffle-pool sequence) would be required in a stream reach (length 1 km) to obtain reliable as well as cost efficient data. Our model showed that the optimal sample size should be determined by interactions between minimum sample size, the degree of data reliability, and cost efficiency.

• 한국습지학회지
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• 제6권3호
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• pp.83-93
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• 2004

본 연구의 목적은 하천환경의 정량적 평가기법을 통해 하천 관리 전략의 틀을 개발하는데 있다. 연구 대상지는 경남 진주시를 관통하여 남강으로 유입되는 6개의 지방 하천이다. 하천환경 평가는 세 가지의 현장 조사를 통해 수행되었다. 첫째, 대상 하천의 제방선으로부터 좌우 50m, 길이 500m 간격을 단위구간으로 하여 20개의 평가항목에 대해서 하천 자연도를 조사하여 5등급으로 평가하였다. 둘째, 수질 및 유량을 8회 조사하여 5등급으로 평가하였다. 셋째, 해당 하천 유역의 토지이용도를 주거지 비율을 따라 5등급으로 평가하였다. 이상의 하천환경의 세 가지 부문인자인 자연도, 수질 그리고 토지이용도를 통합하여 다시 5등급으로 분류하여 최종적인 하천 환경을 평가하였으며 그 결과에 따라 각 하천별 관리 전략을 제시하였다. 하천별 적용 결과를 살펴보면, 판문천과 가좌천은 적극적인 환경복원이 필요한 IV등급으로 평가되었고, 나불천과 용아천은 부분적 복원이 필요한 II등급으로 평가되었으며, 영천강과 독산천은 현 상태 유지가 바람직한 I등급으로 평가되었다. 이상의 대상 하천별 환경 평가는 향후 하천관리 계획수립이나 하천 복원을 위해 중요한 참고자료가 될 것으로 기대된다.

• 농촌계획
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• 제12권4호
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• pp.83-88
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• 2006

Recently, management and restoration efforts using the plants promote the disturbed habitats such as a set-asides or field boundaries. But, side effects are coming out because of using the exotic plants in restoration process. This study was conducted to select the native plant species used for restoration through the vegetation survey and plant community analysis at small stream-side in rural villages. We surveyed at two small stream-sides in open field and high land area in 2005 as a case study. Total 126 species was found at small stream side in open field area. As the result of important value' calculation, Persicaria thunbergii 23.0%, Humulus japonicus 18.6%, Phragmites communis 4.4%, Bromus japonicus 4.2%, and Rosa multiflora 3.4% were in the order of important value. Total 92 species were found at small stream side in high land area. As the result of important value' calculation, Dactylis glomerata 16.1%, Artemisia princeps var. orientalis 11.0%, Persicaria thunbergii 10.9%, Humulus japonicus 9.3%, Phragmites japonica 5.2% and Phragmites communis 3.5% were in the order of important value. We selected some plant species to use in restoration after due consideration of problems of exotic plant and high coverage and density species, and ecological process; Persicaria thunberii, Phragmites communis, Bromus japonicus, Rosa multiflora, Equisetum arvense, Digtaria sanguinalis, Impatiens textori, and Artemisia princeps var. orientalis in open field stream-side, and Artemisia princeps var. orientalis, Persicaria thunbergii, Phragmites japonica, Phragmites communis, Artemisia selengensis, Panicum bisulcatum, Rorippa indica, and Equisetum arvense at hghland stream-side. We will verify the selected native plants and plan the utilization of the native plants in restoration at stream-side in rural village.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.719-722
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• 2008

Forest management is done to keep ecological health of forest and to enhancement of its function. Nowadays, the abnormal climate and heavy rain happen frequently. Therefore, there are opinions that the thinning slash allowed in the mountain is flowed in rivers, which can influence in flood damage. This study, we grasp moving characteristics of thinning slash through field survey and achieved basic study about the effect of thinning slash on the discharge capacity of rivers and stream structure.

• 대한토목학회논문집
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• 제28권3B호
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• pp.283-296
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• 2008

본 연구에서는 현재의 하천상태를 진단할 수 있는 도시하천 평가기법을 제시하였다. 이를 위해 국내 외 하천평가에 대한 문헌 및 연구자료를 조사하고 비교 분석하였으며, 예비하천조사를 실시하고 도시하천의 특성 및 하천의 치수기능 등을 고려하여 하천의 상태를 평가할 수 있는 평가인자를 도출하였다. 도시하천 평가기법은 상위단계, 중간단계, 하위단계의 3단계로 구성하였다. 상위단계에서 하천의 기능을 고려하여 제방, 하천, 생태환경의 3개 특성으로 구분하고, 중간단계에서는 3개 특성이 변형되고 훼손된 정도를 설명할 수 있는 10개의 평가부문(제방, 수로, 흐름, 하상, 비인공화 정도, 저수로변과 홍수터, 하천주변, 동물상, 식물상, 수질)으로 나누었으며, 하위단계에서는 도출된 53개의 평가항목을 구성요소로하여 단계적 평가가 가능한 평가기법을 제시하였다. 특성간, 평가부문간 가중치를 산정하기 위하여 하천전문가를 대상으로 설문조사를 실시하고, 이를 AHP(Analytic Hierarchy Process)를 이용하여 분석하였다. 하천의 규모와 복원정도를 고려하여 수원천, 안양천, 중랑천을 대상하천으로 선정하고 평가를 실시하여 도시하천 평가기법의 적용성과 평가정보의 가치 수준을 확인하였다. 평가결과는 항목지수, 부문지수, 특성지수, 총괄지수 및 평가등급으로 하천의 상태를 나타냈다. 본 연구에서 제시한 하천평가기법에 따른 하천평가결과는 하천이 변형되고 훼손된 부분과 정도를 파악함으로써 도시하천의 복원과 관리에 필요한 기초자료로 활용되어 질 수 있을 것으로 판단된다.

• 한국물환경학회지
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• 제25권2호
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• pp.235-244
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• 2009

The purpose of this study is to offer information about the current river conditions and basic data of streams in Busan city, by selecting 20 underground streams and evaluating their multilateral stream assessment. Concerning the evaluation of streams, 4 sections including the general index, the bank index, the river characteristic index, and the ecological environment characteristic index were evaluated. Ahead of the evaluation, the study divided Busan city into 4 zone for a systematic river investigation. Then, the study allocated code names to each river, and conducted literature research and a field survey of streams. Based on this, the study applied the evaluation of multilateral stream assessment. As a result, out of 4 entire grades, there was no grade 1 or grade 2. Instead, 35% were grade 3, 60% were grade 4, and 5% were grade 5. When looking into the evaluation results by Zone, the Dongbusan Zone showed the highest index, and the Suyeonggang Zone, the Jungbusan Zone, and the Nakdonggang Zone followed, in order.

• Journal of Ecology and Environment
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• 제32권3호
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• pp.197-206
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• 2009

Benthic macroinvertebrate communities were collected from six different sites in the Dobong Stream in Seoul, Korea to investigate spatial and temporal changes in benthic macroinvertebrate communities in response to natural disturbances such as floods and droughts. We collected samples monthly or semimonthly with a Surber net ($30cm{\times}30cm$), and measured environmental factors, including stream temperature, discharge, width, conductivity, dissolved oxygen and pH at each sampling site. Benthic macro invertebrates were strongly affected by floods as well as droughts. In addition, benthic macroinvertebrate communities displayed different responses to the onset of the rainy season in summer 2006 and 2007, apparently due to differences in the intensity and amount of precipitation. Chironomids were particularly sensitive to heavy rain. Floods and droughts also affected the proportions of functional feeding groups during the survey period: the proportion of scrapers was high right after heavy rains, while the proportion of predators tended to increase in intermittent-type streams as the riffle zone decreased. Finally, although species richness and abundance were strongly influenced by heavy rain, they recovered to background levels for within one month, and varied consistently among stream types, indicating habitat stability.

• 한국농공학회논문집
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• 제52권4호
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• pp.53-61
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• 2010

An impervious cover in the watershed management has been used as effective indicators. It is a very useful barometer to measure the impacts of watershed development on aquatic systems. Hence, it is necessary to survey the impervious cover of a watershed and to develop an impervious cover model (ICM) for supporting best management practices. The main objectives of this study were to investigate the spatial patterns of the impervious cover, to calculate landscape indices using FRAGSTATS, and to develop an ICM in the Gap-stream watershed and its six sub-watersheds. The results showed that the impervious cover of the Gap-stream watershed increased from 4.9 % in 1975 to more than 11.2 % in 2000, the number of impervious cover fragments increased from 662 to 3,578, and the landscape shape index increased from 27.0796 to 91.1982. Fragmentation was severe within the Yudeungcheon downstream and the Gapcheon downstream of six sub-watersheds. This paper presented the results derived landscape indices to define landscape patterns and structure for the Gap-stream watershed. Our results indicate that altered land use might be influenced changes in landscape structure.

• 한국환경보건학회지
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• 제11권1호
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• pp.1-8
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• 1985

Urban sewage and stream water in Wonju city were examined and the results were as follows: The average water quality of Wonju stream was flow 52.8m$^3$/min, BOD 21.14ppm, COD 7.06 ppm, SS 212.4ppm, Cl$^-$ 23.14ppm, O-Phosphate 1.08ppm, NH$_3$-N 1.08ppm, NO$_2$-N 2.63ppm and pH 7.48 respectively. The average water quality of urban sewage was flow 2.76m$^3$/min, BOD 112.7ppm, COD 33.6ppm, SS 374.4ppm, Cl$^-$ 46.2ppm, O-Phosphate 1.56ppm, NH$_3$-N 5.96ppm and NO$_2$-N 3.28 ppm respectively. The quality of stream water showed was 4th grade area according to environmental water quality standard. The survey showed k$_1$ 0.11day$^{-1}$, k$_2$ 0.29day$^{-1}$ and the self- purification coefficient 2.5 in average.. In calculating oxygen variation in water by Streeter-Phelp's equation the zero station exhibited in down stream.

• 환경위생공학
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• 제10권1호
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• pp.66-75
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• 1995

This survey is executed about the water quality and improvement measure of Imjin- river. The results are summarized as follows; 1 ) Ammonia nitrogen concentration in tap water was two times higher than drinking water standard. 2) The concentration of BOD in textile wastewater was 235ppm which is higher than wastewater distribution standard and leather wastewater showed high nitrogen concentration. 3) Water quality of the Imjin- river upstream was not in problem but that of Shin- stream showed somewhat high concentration in BOD, COD, and ammonia nitrogen. Especially the detected Cynide compound on the lower of Shin- stream implied seriously polluted condition. 4) The heavy metal in soil of the river bed was not detected but iron, zinc was detected to high concentration. 5) It Is urgently suggested to build more municipal sewage and sanitary treatment plants, and run dredging and river bed rearrangement project. 6) The Construction of the wastewater treatment complexes of relevant industries shall be propelled as soon as possible.