• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.547-547
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• 2015

본 연구에서는 달천구간 (괴산댐~송동보)에서 어류 군집 (Fish Community)을 고려한 생태학적 최적유량 (Ecological Optimum Discharge)을 산정하였다. 이를 위해 유량증진방법론(IFIM: Instream Flow Incremental Methodology)을 기반으로 한 2차원 모형인 River-2D를 적용하여 수리해석 및 대상어종 (Target Fishes)에 대한 가중가용면적 (WUA: Weighted Usable Area)을 산정하였다. 모형 검증을 위해 김원 등 (2007)에 의해 수행된 과업구간 내 수위 및 유량 모니터링 자료를 활용하였으며, 하류경계조건은 김지성 등 (2007)에 의한 수위-유량 관계곡선식을 활용하였다. 또한 평저류량 조건에서의 조도높이 (Roughness Height) 산정을 위해 유량 및 하상재료의 영향을 고려할 수 있는 멱함수 및 반대수함수 형태의 조도계수 공식을 적용하였다. 모형검증 결과 River-2D에 의해 계산된 수위값이 모니터링값과 비교적 잘 일치함을 알 수 있었다. 대상유역에 대한 어류 모니터링 (에코리버21사업단, 2007~2010) 결과를 바탕으로, 과업지역내 우점종 (피라미), 아우점종 (쉬리 등 3개 어종), 멸종위기어종 (묵납자루)을 대상어종으로 선정하였으며, 대상어종에 대한 서식도적합도지수 (HSI, Habitat Suitability Index) 산정을 위해 IFASG (Instream Flow and Aquatic Systems Group) 방법 및 WDWF (Washington Department of Fish and Wildlife) 방법을 적용하였다. 수심, 유속, 하상재료 및 하상형상에 대한 서식도적합도지수가 5가지 대상어종에 대해 각각 산정되었으며, 복합적합도지수 (CSI : Combined Suitability Index)를 고려한 과업대상 위치별 어류의 발생확률이 모의되었다. 어류 군집에 대한 가중가용면적 (WUA)이 최대로 되는 생태학적 최적유량 산정 결과, Type I~III의 경우 모두 $10m^3/s$ 이하의 유량조건에 대해서 WUA가 최대값을 갖는 것을 확인할 수 있었으며, 납자루속의 어류 (Type III)의 WUA가 000 및 000속 (Type II)의 어류에 비해서 작은 유량에서 더 큰 값을 갖으며, $10m^3/$s 초과 유량에 대해서는 반대의 경향이 나타나는 것을 확인할 수 있었다.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1811-1815
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• 2016

Wetland geographical areas have a higher incidence of Opisthorchis viverrini-associated cholangiocarcinoma (CCA), confirmed by data from geographic information systems, than other areas. Behavioral data also indicate that people in these areas traditionally eat uncooked freshwater fish dishes, a vehicle for O. viverrini infection. The best approach to reducing CCA incidence is decreasing risk factors together with behavior alteration. Evaluation of CCA risk and its related factors are first needed for planning the prevention and control programs in the future. We therefore aimed to evaluate the CCA risk and explore its related factors among people in wetland communities of Ubon Ratchathani, Thailand. A cross-sectional study was conducted between July and August 2014. In total 906 participants, with informed consent, completed questionnaires. Overall risk of CCA was determined by multiplying odds ratios (ORs) of the risk factors for CCA from literature reviews. A mean score of 5.95 was applied as the cut-off point. Assessment of factors related to overall risk of CCA was accomplished using conditional logistic regression. Of all participants, 60.15% had a high level of the overall risk of CCA. Factors related to the overall risk of CCA were gender (p<0.001), marital status (p<0.001), perceived susceptibility (p=0.043) and prevention behavior for CCA (p<0.001). In conclusion, most participants in this community had a high level of overall risk of CCA. Therefore, integrated prevention and control programs continue to be urgently required.

• Korean Journal of Ecology and Environment
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• v.40 no.3
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• pp.403-411
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• 2007

The purpose of the study was to evaluate fish community, based on conventional at Shannon-Weaver diversity index (H'), and ecological health, based on the Index of Biological Integrity (IBI) using fish assemblage in the eight sites of Nakdong River during June${\sim}$August 1999. Total number of species sampled was 19 species, and two sensitive species of Zacco temminckii (51%) and Rhynchocypris oxycephalus (28%) dominated the fish community. Also, trophic guild analyses showed that insectivore was 87% of the total and omnivore was rare, indicating that the ecological health is well maintained in the system. The pattern of spatial variation in the diversity index(H') was very similar to patterns of the species number and individual number, whereas the pattern of H' was not matched with the tolerance and trophic guild data. The diversity index (H') showed highest (1.56) in Site 6 where the proportion of sensitive species and tolerant species was minimum and maximum, respectively, and where the insectivore and omnivore were minimum and maximum. In other words, the diversity index was not matched at all with the trophic and tolerant guilds, indicating that the conventional index did not reflect the ecological characteristics of fish community in the system. In the mean time, the ecological health (IBI) averaged 33.5 (n=8), indicating "good${\sim}$fair condition" and the IBI values matched with trophic and tolerance guilds. Maximum IBI occurred in Site 2 where the sensitive and msectivore species were nearly maximum, and the tolerant and omnivore species were almost minima, indicating that IBI values were closely associated with the ecological functions and health conditions. Overall data suggest that the conventional diversity index may not effective for a evaluation of fish community, and that in contrast the IBI approach may be a useful tool for diagnosis of stream community.

• Journal of Environmental Science International
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• v.22 no.8
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• pp.925-935
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• 2013

In this study, a comprehensive field monitoring was conducted to understand habitat conditions of fish species in up and downstream of Hoengseong Dam. Based on the monitoring data, riverine health conditions such as composition ratio of fish species, bio-diversity (dominance index, diversity, evenness and richness), index of biological integrity (IBI) and qualitative habitat evaluation index (QHEI) were assessed, and optimal ecological flowrates (OEF) were estimated using the habitat suitability indexes (HSI) established for three fish species Coreoleuciscus splendidus, Pungtungia herzi and Microphysogobio longidorsalis selected as icon species using the physical habitat simulation system (PHABSIM). The total number of species sampled was 20 species, and two species of Zacco platypus (30.4%) and C. splendidus (20.9%) dominated the fish community. As a result, it was revealed that IBI and QHEI values decreased from upstream to downstream along the river. The estimated IBI value ranged from 24 to 36 with average being 30.9 out of 50, rendering the site ecologically fair to good health conditions. HSI for C. splendidus were determined according to three different month in terms of season: Spring (April), Summer (August) and Autumn (October). HSI for flow velocity were estimated at 0.7 to 0.8 m/s for the Spring, 0.5 to 1.0 m/s for the Summer and 0.8 to 0.9 m/s for the Autumn. HSI for water depth were estimated at 0.3 to 0.5 m for the Spring; 0.3 to 0.5 m for the Summer; and 0.3 to 0.4 m for the Autumn. OEF was estimated at 4.2 and $6.5m^3/s$ for the Spring and Autumn, and $12.0m^3/s$ for the Summer. Overall, it was concluded that the Hoengseong Dam has been relatively well protected from the anthropogenic disturbance for the legally protected species including the endemic species studied in this study.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.8
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• pp.564-571
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• 2011

In order to establish fundamental data for stream restoration and environmental flow, we investigated fish fauna, community and physical habitat conditions in the Dal Stream of Han River Basin. Field monitoring including fish sampling was conducted from September 2008 to October 2009. A total number of fish caught in the 5 sites was 2,080 representing 9 families 35 species, and 19 species (54.3%) including Acheilognathus koreensis and Iksookimia koreensis were Korean endemic species during the study period. The most frequently found species in number was pale chub (Zacco platypus, 25.7%, n = 632) followed by Coreoleuciscus splendidus (18.0%, n = 375) and Z. koreanus (13.0%, n = 272). The lower reach of Dal Stream was more abundance of species, high diversity, evenness and richness, and lower dominance index than those of the upper reach. According to the dendrogram established at 0.63 level of similarity rate, sampling stations were divided into 2 groups. Most of upper streams in Korea consist of riffles and runs that are repeatedly followed by another one. However, stream channelization and leveling have caused reduction of habitat diversity. Therefore, it is necessary to make an effort on stream rehabilitation with evaluation of physical habitat condition by indicator species in order to maintain biodiversity and perform ecological restoration.

• Korean Journal of Ecology and Environment
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• v.42 no.2
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• pp.172-182
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• 2009

This study was to analyze characteristics based on tolerance and trophic guilds and to determine the level of total mercury in tissues of sentinel species, Zacco platypus at 3 sampling sites of the Mangyeong River in 2007. Total sampled fishes were 26 species and the most dominant species was Zacco temminckii (47%). Fish community analysis was resulted that eveness index and diversity index showed low value at S1. However, diversity index and richness index at other sites showed high. According to various guilds analysis, relative abundance of sensitive species was 70% and 42% at S1 and S2, respectively. While sensitive species were decreased (1%) and tolerant species were increased (60%) at S3. It was mainly carried to the impacts of wastewater treatment plants near the location. Relative abundance of insectivore species was decreased from up (S1) to midstream area (S3). In addition, chemical water quality, based on analyses of BOD, COD, TP, TN, EC, MPN and SS concentration showed similar trends. Qualitative Habitat Evaluation Index (QHEI) was averaged 164, judged as "good" habitat condition. Average concentrations of total [Hg] was 146.9 ${\mu}g$ $kg^{-1}$. In the muscles of total [Hg] was the highest, and then followed by kidney, vertebrae, liver, and gills. According to FDA standards (500 ${\mu}g$ $kg^{-1}$) of Korea, total [Hg] has not affected to the individual fish health.

• Journal of Environmental Health Sciences
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• v.45 no.1
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• pp.42-53
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• 2019

Objectives: The Yongpung reservoir in Korea is a crucial facility that supplies water to farms in its surrounding $2km^2$ area. However, its water quality is not suited to the needs of current residents who wish for the availability of environmentally friendly agricultural products and desire to use the waterfront area. The aim of this research was to evaluate the reservoir's fish and benthic macroinvertebrate distributions and determine its water quality and the heavy metal content in its sediment. This basic data can be used to establish environmentally protective plans for the Yongpung reservoir. Methods: Six sites were selected for analysis in this investigation. Three points (YP-1, YP-2, and YP-3) were evaluated for water quality and metal content in sediments; they were located upstream, midstream, and downstream of the reservoir. Samplings of the fish and benthic macroinvertebrate populations were performed at three other sites: St. 1, St. 2, and St. 3. Results: Based on chemical oxygen demand (COD) and total nitrogen (T-N) data, the quality of the Yongpung reservoir water corresponds to Class VI (very poor) according to Korea's lake environmental standards. The lead levels measured in the sediment at the midstream and downstream points of the reservoir were 76.7 and 72.7 mg/kg, respectively, while 8 orders, 15 families, and 16 species of benthic macroinvertebrates were identified in the reservoir. The ecological score of the benthic macroinvertebrate community (ESB) was between 8 and 23, denoting poor to very poor environmental conditions. Further, 4 families and 7 species of fish were identified in the reservoir, with Cyprinidae accounting for 94.3% of all observed freshwater fish. Conclusion: Based on these findings, we conclude that management plans, including the removal of lead from the sediment, are necessary to improve the quality of the agricultural water in this reservoir. The T. japonica, which cover almost 30% of the water area, must also be removed.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.327-336
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• 2007

This study assessed ecological health using a multi-metric fish model from 15 sites in the headwater watershed of southern Han River during June${\sim}$August 1999 and then compared the health with conventional community diversity index to figure out differences between health and diversity index. For the analysis, we adopted 10 metric IBI model for regional applications. During this survey, total number of species sampled were 24 (6 families) and varied depending on magnitude of ecological disturbance and stream order. In the mountainous streams, mean proportion of sensitive and insectivore species was composed of 91% and 56%, respectively, indicating a potential healthy conditions. However, tolerant species with 66% and omnivore species with 76% were sampled from the 2nd order stream, which was shown deterioration in the physical habitat quality. In the overall watershed, mean IBI value was 38, judging as "fair" condition by the health criteria. Values of Individual IBI were closely associated with stream order and this pattern was similar to other mountainous streams showing low chemical pollutions and disturbance. Our comparison between IBI and diversity index over the stream order showed a distinct difference; Shannon-Weaver diversity index overestimated the actual community conditions and the variation range in the 2nd order stream was greater in the diversity index. Overall data suggest that the multi-metric approach may to a useful tool for stream ecosystem management and the conventional diversity index may not effective unless the stream order is considered for the stream evaluation.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.3
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• pp.240-248
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• 2006

In this study, a retrofitting BNR process that was modified for the economical applicability was proposed and evaluated in the pilot plant($50m^3/d$). At the same time the bacterial community structure was investigated in the pilot plant by using FISH(fluorescent in situ hybridization) method. Economically 16% of the initial construction cost for the proposed process(introduction of a biological nutrient removal process of $60,000m^3/d$ scale basis) was reduced due to the absence of a bioreactor. Water treatment efficiencies and maintenance facilities of the modified process were satisfied with the strengthened discharge permits in Korea throughout a long term pilot plant operating including a winter season. Bacterial populations in the pilot plant and in the control plant(A2/O process, B SIP(Sewage Treatment Plant)) were remained uniformly during the test period, but bacterial structure in the bioreactor was changed drastically. Proportions of ${\beta}$-proteobacteria group including soil bacteria which play a important role in wastewater treatment increased $25{\sim}607%$ in population.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.5
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• pp.735-745
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• 2022

In this study, a health assessment was conducted using the Benthic Health Index (BHI) to assess fish cage farms, where a fishery environment assessment was also performed. A total of 43 farms were evaluated located in the East Sea, West Sea, and South Sea in Korea. The results of the BHI health evaluation included 8 grade 1 farms, 4 grade 2, 12 grade 3, and 19 grade 4. The grade 1 farms included sandy sediment farms and those with low intensity aquaculture, while the grade 2 farms included those located in areas with active seawater circulation. The fish cage farms belonging to grade 3 and 4 included the majority of farms with high-intensity aquaculture activities. There was no significant difference in total organic carbon between grade 3 and 4 farms, but the results of polychaete community analysis show that organic matter concentration was significantly higher in grade 4 farms.