• Title/Summary/Keyword: River

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The Karyotype of a Riceash, Oryzias latipes from Southern Korea (한국 남부지방에 서식하는 송사리 Oryzias latipes (Temminck et Schlegel)의 핵형)

  • 김익수;문교정
    • The Korean Journal of Zoology
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    • v.30 no.4
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    • pp.379-386
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    • 1987
  • Karyotype of the ricessh Orygias latipes (Temminck et Schlegel) was investigated using 151 specimens of eleven populations in the southern Korea. Based on the karyotype analysis, two distinct chromosomal groups were found. One group, occurring in the Kum River, the Mankyong River, the Dongjin River, the Ysngsan River and the SEmjin River had a diploid chromosome number of 46 and arm number of 70, which contained one pair of "large" metacentric chromosomes. The other group, occurring in the Tamjin River, the Hyongsan River andthe all four island populations observed had a diploid chromosome number of 48 and arm number of 68. These results showed that 0. latipes of 6 inland populations was identical with the Chinese population in diploid number, arm number and presence of "large" metacentric chromosome, while the present species of island populations ana populations of the Tamjn R. and Hyongsan R. was similar to the Japanese population in chromosome number and arm number. The karyotype variation in populations indicated that karyotypes will probably provide useful information in studying zoogeography of this species.phy of this species.

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Evaluation of Water Quality using Principal Component Analysis in the Nakdong Rivev Estuary (주성분 분석법을 이용한 낙동강 하구 해역의 수질 평가)

  • Sin, Seong-Gyo;Park, Cheong-Gil;Song, Gyo-Uk
    • Journal of Environmental Science International
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    • v.7 no.2
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    • pp.171-176
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    • 1998
  • This study was conducted to evaluate water quality utilizing principal component analysis in the Nakdong River Estuary. From the results of analysis, water quality in the Nakdong River Estuary could be explained up to 65.3 Percente by three factors which were Included In river loadlnwastes from the Nakdong River and rainfalls : 39.1%1, sediment resuspension(13.7BS) and metabolism(12.5%). In the eastern part of estuary In flowing the Nakdong River, river loading factor score(factor 1 Pas higher than that In western part. Sediment resuspension factor score(factor 2) was high in shallow water, while metabolism factor score(factor 3) was high in deeper water. For seasonal variations of factors score, factor 1 was h19h- 1y related to rainfall season.

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An initial study on ecological environment changes after emergent water transportation at lower reaches of Tarim River, China based on remote sensing technique

  • Jianli, Zhang;Lin, Li;Longjiang, Du
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.313-315
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    • 2003
  • Tarim River is the longest continental river in China. Its downstream ecological environment declination and valley remedy got great concern. To improve ecological environment of lower Tarim River, “Emergent water transportation project for Tarim river valley remedy” was carried out from May 2000. Water was transported five times till May 2003. Several periods MODIS image was used to monitor water body in river channel. Two periods ETM image was used to interpreter changes of environment. Area of vegetation in 1999 was similar with 2001, but become better in total. The normalized difference vegetation index (NDVI) and vegetative coverage reflected environment changed better.

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The Characteristic of Point Source Loads for Nitrogen and Phosphorus to Gwangyang Bay, Korea (광양만으로 유입되는 질소, 인의 점원 오염부하 특성)

  • Kim Do-Hee;Cho Hyeon-Seo;Lee Young Sik
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.8 no.1
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    • pp.1-8
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    • 2005
  • We estimated the loadings of nitrogen and phosphorus flowing into Gwangyang Bay front river for monthly interval from April to December of 2003. We analyzed the concentrations of nitrogen and phosphorus in water and estimated the flowing rates of fresh water in 34 rivers. The amounts of water flowing into the Gwdngyang Bay from Sum-Jin River was 51-76% in the total inflow of the river. The river water over 96% of discharge was from Sumjin River, Dong River, Ju-Kyo River, Seo River and Shinkyum River. The flowing patterns of nitrogen and phosphorus into Gwangyang Bay were similar to the flowing of river. The nitrogen and phosphorus loadings into the Bay were higher in July and August than in dry seasons. In particular, the concentrations of phosphorus were high in Namshu River, Deukyang River and Kilho River sewage during in dry seasons. The range of DIN and TN loadings from Sumjim River were 46-66% and 36-64%, respectively. The loading of DIP and TP from Sumjim River were 2-55% and 12-67%, respectively. These results show that the most efficient control of N. p flow into Gwangyang Bay is to restrain the inflows of N, p from Namshu River, Deukyang River and Kilho River and to restrain the flows of N, p from Dong River, Ju-Kyo River and industrial plant. The DIN/DIP atom ratio in river water was about 18 in July and August, while the ratio was more higher in dry seasons than July and August of rainy seasons. The TN/TP atom ratio in river water was about 7 in rainy seasons, while the ratios were higher than 100 in the other months of dry seasons.

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Distribution Patterns of Benthic Macroinvertebrates in Streams of Korea (우리나라 주요 하천 수계에서 저서성 대형무척추동물의 분포 특성)

  • Kwak, Ihn-Sil;Lee, Dae-Seong;Hong, Cheol;Park, Young-Seuk
    • Korean Journal of Ecology and Environment
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    • v.51 no.1
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    • pp.60-70
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    • 2018
  • The distribution of benthic macroinvertebrates was investigated at 1,157 sites of 7 main water systems in Korea, including 442 sites of Han River system (Namhan River, Bukhan River, Han River main stream, Anseongcheon, etc.), 305 sites of Nakdong River system (Nakdong River, Hyeongsan River, Taehwa River, etc.), 199 sites of Geum River system (Geum River, Sapgyocheon, Mangyeong River, Dongjin River, etc.) 102 sites of Seomjin River system (Seomjin River), 102 sites of Yeongsan River system (Yeongsan River, Tamjin River, etc.), and 7 sites of Jeju stream system. A total of 151 families were found in the whole survey sites, including 141 families in Han River, 122 in Nakdong River, 115 in Geum River, 106 in Seomjin River, 113 in Yeongsan River, and 50 in Jeju. Chironomidae (20.8%) was the most dominant species in Korea, followed by Hydropsychidae (17.1%), Baetidae (12.6%), Tubificidae (10.3%), Heptageniidae (8.6%), Ephemerellidae (6.3%), Asellidae (2.7%), Leptophlebiidae (2.4%), Planariidae (1.7%), and Tipulidae (1.6%). Substrates compositions consisted of large sand (22.6%), large gravel (18.4%), silt (10.5%), and boulder (8.2%). The mean stream width was 133.5 m and the mean watercourse width was 61.7 m. The mean water depth and velocity were 30.2 cm and $33.1cm\;s^{-1}$, respectively. Results of cluster analysis based on distributional characteristics of benthic macroinvertebrates were divided into six groups according to the frequency of benthic macroinvertebrate taxa which appeared in the study area. Finally, altitude, current velocity and substrate composition were the most influencial factors determining the distribution patterns of macroinvertebrate communities.

Study on the long-term change of Chlorides in the tidal area of river (하천 감조부에 있어서 염분의 장기변동에 관한 연구)

  • 김원규
    • Journal of Environmental Science International
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    • v.3 no.1
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    • pp.11-16
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    • 1994
  • Generally, it is difficult to predict water quality in a tidal river, because tidal flows make the transport phenomena more complicated. The purpose of this study is to clarify long-term mass transport in a tidal river through suggestion of simulation model. A simulation model based on a Lagrangian coordinate system, which has the advantage reducing numerical dispersion, was used to calculate changes in concentration of chlorides. Several field surveys were conducted to verify calculated results. Concludingly, long-term behavior of mas transport in a tidal river can be represented using the model.

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The study on the schematic design of outdoor lighting for Han river bridges (한강교량 경관조명의 기본계획에 관한 연구)

  • 정근영;정봉근;이준형;최안섭
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2001.11a
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    • pp.27-30
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    • 2001
  • This paper describes the geographical and cultural characteristics of Han river and presents a schematic design of outdoor lighting for Han river bridges. Basic design concept for Han river and detail theme for each bridge was developed. With lighting simulation program, lamp, color, and image of bridge in Han river modeled and simulated. Lighting visualizations of the three major bridges were shown and detail design concept for such bridges were introduced.

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Molluscan Fauna in Lower Part of Han River, Korea (한강 하류의 패류 분포상)

  • 김재진
    • The Korean Journal of Malacology
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    • v.14 no.2
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    • pp.161-166
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    • 1998
  • Mollusks were collected with Ponar grab from seven stations in lower part of Han river, Korea from June 1995 through May 1996. Basket sampler with artificial substrate was also employed to collect the adhesive mollusks. In addition to above mentioned sampling stations, Bam islet was surveyed. A total of species, Corbicula fluminea, Anodonta woodiana, Unio douglasiae, Limnoperna fortunei, corbicula fenouilliana and Physa acuta, were collected in lower part of Han river. Author reviewed the literatures on the ecological survey of molluscan fauna in Han river.

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The System of Sewage and Domestic Wastewater Treatment Plants in Tan-Sui River Basin

  • Ko, Chun-Han
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2002.04a
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    • pp.26.2-39
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    • 2002
  • Tan-Sui River Basin covers Taipei metropolitan area of 2,726 square kilometers with more than six million residents. Since 1988, Taiwan government started to plan and construct an integrated sewerage system, consisted by both separated and concentrated trunk sewers, wastewater treatment plants and ocean outfalls. This presentation will introduce the master plan and major facilities of Tan-Sui River Basin sewerage system. Other measures to protect general water quality and the environment of adjacent river basin area of Tan-Sui River and her tributaries by Taiwan EPA will be presented as well.

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Characteristics of Meteorological Environment Variation Before and After Construction of Nak-dong River Estuary Barrage (낙동강 하구둑 건설 전·후의 기상환경 변화 특성)

  • Jeon, Byung-Il
    • Journal of Environmental Impact Assessment
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    • v.14 no.3
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    • pp.135-145
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    • 2005
  • This study was conducted to investigate the characteristics of meteorological environment variation before and after construction of Nak-dong river estuary barrage. We used meteorological data(air temperature, precipitation, relative humidity, visibility, wind) at Gimhae airport meteorological station. The construction of river estuary barrage can change climate at the neighboring districts and influence human's health and vegetable. The construction of Nakdong river estuary barrage brought rise of temperature, decrease of relative humidity and increase of poor visibility frequency.