• 한국물환경학회지
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• 제26권1호
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• pp.104-110
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• 2010

Eutrophication is a well-known phenomenon in lentic habitats, however it is receiving increasing attention in shallow streams of Korea due to the increase of periphyton to a nuisance level. In this study temporal and spatial variation in periphyton standing crop and nutrient concentrations were surveyed in the upper reach of the Han River (the Inbuk Stream) that used to be a pristine rural stream until 1980s. Chlorophyll-a concentration per unit surface area of bottom substrate was examined monthly for one year period at nine sites along the Inbuk Stream together with environmental factors such as phosphorus, nitrogen, and water velocity. The standing crop of periphytic algae ranged from $4{\sim}242mgChl.a/m^2$ with a median of $55mgChl.a/m^2$, often exceeding the nuisance level criterion. Along the stream periphyton increased significantly from $39{\pm}48mgChl.a/m^2$ to $94{\pm}49mgChl.a/m^2$ after merging of a tributary in an intensive agricultural basin with high phosphorus concentrations. Seasonally periphyton biomass was highest in autumn (median $171{\pm}76mgChl.a/m^2$) from October through December when water flow velocity was low (median $0.4{\pm}0.3m/s$), while it was higher in flood season (median $1.2{\pm}0.4m/s$) and freezing season (median $0.2{\pm}0.3m/s$) was lower. The result shows that this rural stream often shows characteristics of eutrophication according to periphyton standing crop and it may be regulated by phosphorus and water velocity.

• 한국수자원학회논문집
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• 제34권5호
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• pp.543-549
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• 2001

수리학적 하도추적으로부터 하천유량을 간접추정하였다. 짧은 하천구간의 세 지점 연속수위자료와 하천 단면 자료만을 사용하여 조도계수 추정b과 하천유량 계산이 가능하였다. 유량의 간접추정 과정에서, 상류-하류 경계조건을 수위-수위 조건으로 사용하였다. 미국 미시시피 강의 상류 구간 자료가 사용되었고 수리학적 하도추적에는 DWO-PER (operational dynamic wave model)를 이용하였다. DWOPER 모형에서 수정 Newton-Raphson법에 의한 조도계수 추정과정을 개선하기 위하여 SCE-UA 전역최적화 기법을 적용하였으며, SCE-UA 기법의 결과가 적은 오차를 보였다. 특정 홍수에 대하여 유량을 추정한 결과, 몇 개를 제외한 대부분의 계산유량이 10% 이내의 오차를 보였다.

• Animal cells and systems
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• 제15권3호
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• pp.235-241
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• 2011

To examine variation in trophic pathways and the characteristics of food webs from organic matters to aquatic insects, we used stable isotopes to study an intermittent stream system of the Inukami River, Japan. The aquatic insects, including Glossosoma spp., Chironominae spp., Stenelmis spp., Rhyacophilla nigrocephala, and Hexatoma spp., were characterized by different feeding strategies. The ${\delta}^{13}C$ values for these species indicated that Glossosoma spp. graze upon periphyton; Chironominae and Stenelmis spp. mainly feed on benthic particulate organic matter, and R. nigrocephala and Hexatoma spp., which were identified as predators, feed upon Glossosoma, Stenelmis, and/or Chironominae spp. This suggests that the trophic position of consumers at each station may be determined by the trophic position of basal food sources in situ. For trophic pathways, the ${\delta}^{13}C$ values for both organic matter and aquatic insects tended to gradually decrease, whilst the ${\delta}^{15}N$ values increased from the upper reach to the lower reaches, relative to the physicochemical and geographical conditions. These parameters indirectly influence the flow of energy from organic matter to consumers within food web in an intermittent stream system.

• The Korean Journal of Ecology
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• 제21권5_1호
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• pp.435-448
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• 1998

The phytosociological investigation was carried out at 32 sites of the riparian vegetation in Musim-Chon stream passed through Choengju-City, Chungcheongbuk-Province by Braun-Blanquet's method from August to October, 1997. The flora of vascular plants in this survey was 202 species. The riparian vegetation was classified into 25 communities as follows. The submerged hydrophytes are Potomogeton malaianus var. latifolius community, Potomogeton crispus community, Myriophyllum verticillatum community-Hydrilla verticillata community and Ceratophyllum demersum community. The floating-leaved hydrophyte is Trapa japonica community. The emerged hydrophytes are Phragmites communis community, Perzicaria thunbergii community, Phragmites japonica community, Oenanthe javanica community, Zizania latifolia community and Persicaria hydropiper community. The herbaceous vegetation of floodplain are Artemisia montana community, Humulus japonicus community, Miscanthus sacchariflorus community, Erigeron anmus community, Impatiens balsamina community, Bidens frondosa community, Setaria viridis community, Ambrosia artemisiifolia var. elatior community and Eragrostis ferruginea community. The woody vegetation of floodplain are Robinia pseudo-acacia community, Stephanandra incisa community and Clematis apiifolia community. The species diversity was low in the upper and down stream, while the diversity was high in the mid stream situated at the center of Choengju-City because of frequent disturbance by citizens. These results suggested that distribution of communities and species diversity was closely related to the disturbance.

• 상하수도학회지
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• 제27권5호
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• pp.661-669
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• 2013

River-water quality has been greatly improved during past several decades with the extraordinary expansion for the wastewater treatment capacities by the government. Research aims to select the priority restoration streams based on the chronicle data for tributaries in Geumgang watershed as the main stream area in the Chungchungnamdo province. The quality of BOD, phosphorus and percent of sewered population on 15 branch streams were compared by the grouping methods. The results of group D streams by category I that exceed 3.0 mg/L for BOD and 0.1 mg/L for phosphorus were Seuksung, Ganggyung and Bangchuk stream. The results of group D streams by category II that exceed 3.0 mg/L for BOD and less than 63.5 % of average percent of sewered population were Ganggyung, Gilsan, Bangchuk and Seuksung stream. The final results of selected streams drawn by the chronicle data which exceeded the standard quality and lower than the average percent of sewered population were Seoksung, Gangeyung and Bangchuk stream. The pollution of rivers in the down streams were more serious than in the upper streams. Their watersheds have to be improved river water quality, especially to extend sewer systems as well as wastewater treatment facilities.

• 한국물환경학회지
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• 제29권6호
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• pp.825-831
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• 2013

The Suwon stream which consists of a mountainous reach, an artificial reservoir and an urban reach provides benthic macroinvertebrates with various habitats. This study was conducted to find out the influence of reservoir sluice control and water quality on benthic macroinvertebrates community in the Suwon stream from June to August, 2011. As a result, substrate composition showed little difference between the upper site (S2) and the lower site of the reservoir (S3). At site S3, water velocity was fastest, and water temperature was lowest due to the intermediate depth discharge of the reservoir. Cheumatopsyche brevilineata which prefer fast water velocity was dominant at site S3. Some biotic indices (H', J, and R) of site S3 decreased significantly whereas Benthic Macroinvertebrate Index (BMI) showed little difference between site S2 and site S3. EPT showed a negative correlation with water temperature. The sluice control of the reservoir leaded variations of water velocity and temperature, and seemed to make the state of aquatic ecosystem worse.

• 한국환경농학회지
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• 제25권1호
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• pp.34-39
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• 2006

남한강 수계의 항금천과 사탄천, 만경강 수계의 익산천, 전주천, 고산천과 정읍천의 수계와 유역을 대상으로 수질, 토지이용현황, 식생을 조사한 결과 항금천, 사탄천과 고산천은 산림지역과 농경지로 구성되고 익산천은 대부분 농경지이며 축산단지가 형성되어 있고 전주천은 도시지역을 많은 범위에서 차지한다. 정읍천은 공업지역과 도시지역이 함께 분포하고 있는 것으로 조사되었다. 하천의 수질은 BOD, T-N, T-P는 익산천에서 가장 높게 나타났고 COD는 전주천에서 높게 조사되었다. 산림지와 농경지가 대부분인 항금천, 사탄천과 고산천은 수질이 양호한 것으로 분석되었다. 하천 식물의 종다양성은 상류보다 하류지역이 익산천을 제외하고 낮게 조사되었다. 생활형의 비교에서는 상류에서는 다년생이 대부분을 차지하고 있으며 하류에는 일년생이 높은 점유율을 보이고 있었다. 하천 수질과 토지이용 그리고 식물의 생활형은 상관관계를 가지며 하천의 농경지와 주거지 같은 인간의 영향이 있는 곳의 생태계의 교란은 하천의 수질과 식생에 영향을 미치는 것으로 판단되었다.

• 생태와환경
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• 제40권4호
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• pp.495-502
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• 2007

Species biotic index (SBI), based on a fish assemblage, was applied to a stream assessment using long-term ecological fish data set (1996 to 2001) in Boryong dam area, which is located in the mainstream of Ungchun Stream of Chungnam province, Korea. According to the methods of Hilsenhoff (1988), the scores of tolerance guild assigned 10 classes to each species by its habitat and feeding guild, but modified current 7 criteria to 5 scoring standards due to unclear borderline among species. Relative abundance in the species number of upper stream guilds was only 7% of the total, whereas the abundance in the species number of middle to downstream upper stream guilds was 64%. Mean SBI, based on dataset in Site 1 during 1995-2001 averaged 5.10, which was judged as a "good" condition by the rank criteria of SBI. Before the dam construction, mean SBI in the Site 1 was 4.61, indicating a "good" condition, but after the dam construction, mean SBI was 5.60, indicating a "fair" condition. Trajectory analysis in the Site 1 showed significantly (One-way ANOVA, $F_{6,21}=3.26$, p=0.02) different among years, reflecting the changes of fish composition and population density by the dam construction, whereas Site 2 showed no significant changes ($F_{6,21}=1.00$, P =0.45) difference among years. Mean SBI prior to the dam construction in the Site 3 was 4.52 but after the construction, the value was 6.30, indicating a distinct difference between the pre- and post-dam construction. Trajectory analysis at the Site 3 supported this fact: Values of SBI showed significantly ($F_{6,21}$=14.37, p<0.01) different. Mean SBI was 4.67 in the Site 4, indicating a "good" condition in the health and the health rank was same as the sampling sites 1, 2, and 4. Trajectory in the Site 4 showed no significant ($F_{6,21}=2.35$, p=0.07) difference among the years. Overall, our trajectory analysis indicated that three of four sampling sites (sites 1, 3, 4) showed significant decreases (n=7, p<0.05) and that the proportions of sensitive species declined evidently in the sites 1 and 2 and the tolerant species increased in the dam sites. Our outcomes may be used as a key data for diagnosis of the long-term ecological impact in the future in the watershed.

• 한국어류학회지
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• 제10권1호
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• pp.77-86
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• 1998

낙동강 중류의 지류인 위천에서 어류상과 서식상황을 1995년 8월에서 1997년 10월까지 약 2년에 걸쳐 조사한 결과를 요약하면 다음과 같다. 본 조사의 결과, 모두 10과 30속 40종의 어류가 채집되었다. 그 중 잉어과 어류가 26종(65.0%)으로 가장 많았고, 다음은 기름종개과 어류가 5종(12.5%), 동자개과 어류가 2종(5.0%)이었고 나머지는 1종씩으로 이루어져 있었다. 한반도 고유종은 Rhodeus uyekii를 비롯한 16종으로 전체 어종수의 40%를 차지하여 매우 높은 고유성을 나타내었다. 하천 전체로 보면 Zacco temmincki(15.46%), Zacco platypus(14.29%), Squalidus gracilis majimae(11.25%)의 3종이 우점종이었으며, Cyprinzιs carpio, Rhodeus ocellatus, Culter brevicauda, Misgurnus mizolepis, Leiocassis ussuriensis, Silurus asotus, Macropodus chinensis, Channaargus의 8종은 상대 풍부도가 0.1% 미만인 희소종이었다. 지역별 종조성을 보면 상류에서는 Moroco oxycephalus, 중상류에서는 Zacco temmincki, Squalidus gracilis majimae 및 Niwaella multifasciata, 중하류에서는 납자루류와 Zacco temmincki, 하류에서는 Zacco platypus와 Microphysogobio속 어류가 우세하게 나타났다. 군집구조의 분석은 본류의 중류인 St. 9, 10, 11과 쌍계천의 중류인 St. 17, 18, 19의 6지점이 가장 안정되고 다양한 군집의 구조를 지니고 있으며, 상류인 St. 1과 4는 소수의 어종이 지배하고 있는 다양성이 낮은 군집구조를 지니고 있음을 나타내고 있다.

• 한국어류학회지
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• 제10권1호
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• pp.67-76
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• 1998

낙동강 중류의 1차지류인 영강의 어류상과 서식상황을 1997년 4월에서 11월까지 18개 조사지정에 대하여 조사한 결과를 요약하면 다음과 같다. 본 조사의 결과, 모두 10과 24속 32 종의 어류가 채집되었다. 그 중 잉어과 어류가 17종(53.1%)으로 가장 많았고, 다음은 기름종개과 어류가 5종(15.6%), 메기과와 꺽지과 어류가 각각 2종, 그리고 나머지는 1종씩으로 이루어져 있었다. 한반도 고유종은 Gobiobotia naktongensis를 비롯한 13종으로 전체 어종수의 40.6%를 차지하여 매우 높은 고유성을 나타내고 있었다. 하천 전체로 보면 Zacco temmincki(32.78%)와 Moroco oxycephalus(15.10%)가 우점종이었으며, Zacco platypus, Pungtungia herzi, Niwaella multifasciata, Odontobutis platycephala의 4종은 보통종이었다. Lampetra reissneri, Pseudorasbora parva, Squalidus chankaensis tsuchigae, Microphysogobio koreensis, Gobiobitia naktongensis, Cobitis rotundicaudata, Nemacheilustoni, Silurus asotus, Silurus microdorsalis, Siniperca scherzeri 및 Oreochromis niloticus의 11종은 상대풍부도가 0.1% 미만인 희소종이었다. 하천의 구배에 따른 지역별 종조성을 보면 상류에서는 Moroco oxycephalus, 중상류에서는 Zacco temmincki와 Moroco oxycephalus, 중하류에서는 Zacco temmincki와 Niwaella multifasciata, 하류에서는 Zacco platypus와 Microphysogobio속 어류가 우세하게 나타났다. 군집구조의 분석은 용암천의 중류인 St. 11과 본류의 중류인 St. 15와 최하류인 St. 18의 3개 지점이 가장 안정되고 다양한 군집의 구조를 지니고 있으며, 조령천의 최상류인 St. 1, 5, 7은 소수의 어종이 지배하고 있는 다양성이 낮은 군집구조를 지니고 있음을 나타내고 있다.