• Title/Summary/Keyword: Red River

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Evaluation of River Water Quality by MBOD Method (MBOD법에 의한 하천의 수질평가 -영산강과 섬진강을 중심으로-)

  • 김명숙
    • Journal of Environmental Health Sciences
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    • v.9 no.1
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    • pp.49-62
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    • 1983
  • Evaluation of water quality of Yeong San river and Seomjin river by using of newly simplified MBOD method was performed. Of course, thought that there is some differences between nutrient demands of heterotrophic bacteria and those of Algae which obtain it by photosynthesis, but it has little influence on evaluation of Algae Growth potential. The result of this study were as follows: 1) In both river, the value of Chemical analysis and MBOD method of inorganic salts reveals as nearly same result. 2) Though organic pollution of Seomjin river is less than that of Yeongsan but inorganic contamination is somewhat advanced BOD 2.8 ppm. and MBOD 340 ppm. in Seomjin river but BOD 22 ppm. and MBOD 480 ppm. in Yeongsan river. 3) Both river have tendency to reveal higher Nitrogen value is MBOD=MBOD -P

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A Study on the Extraction of a River from the RapidEye Image Using ISODATA Algorithm (ISODATA 기법을 이용한 RapidEye 영상으로부터 하천의 추출에 관한 연구)

  • Jo, Myung-Hee
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.4
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    • pp.1-14
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    • 2012
  • A river is defined as the watercourse flowing through its channel, and the mapping tasks of a river plays an important role for the research on the topographic changes in the riparian zones and the research on the monitoring of flooding in its floodplain. However, the utilization of the ground surveying technologies is not efficient for the mapping tasks of a river due to the irregular surfaces of the riparian zones and the dynamic changes of water level of a river. Recently, the spatial information data sets are widely used for the coastal mapping tasks due to the acquisition of the topographic information without human accessibility. In this research, we tried to extract a river from the RapidEye imagery by using the ISODATA(Iterative Self_Organizing Data Analysis) classification algorithm with the two different parameters(NIR (Near Infra-Red) band and NDVI(Normalized Difference Vegetation Index)). First, the two different images(the NIR band image and the NDVI image) were generated from the RapidEye imagery. Second, the ISODATA algorithm were applied to each image and each river was generated in each image through the post-processing steps. River boundaries were also extracted from each classified image using the Sobel edge detection algorithm. Ground truths determined by the experienced expert are used for the assessment of the accuracy of an each generated river. Statistical results show that the extracted river using the NIR band has higher accuracies than the extracted river using the NDVI.

COMPARISON OF RED TIDE DETECTION BY A NEW RED TIDE INDEX METHOD AND STANDARD BIO-OPTICAL ALGORITHM APPLIED TO SEA WIFS IMAGERY IN OPTICALLY COMPLEX CASE-II WATERS

  • Shanmugam Palanisamy;Ahn Yu-Hwan
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.445-449
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    • 2005
  • Various methods to detect the phytoplankton/red tide blooms in the oceanic waters have been developed and tested on satellite ocean color imagery since the last two and half decades, but accurate detection of blooms with these methods remains challenging in optically complex turbid waters, mainly because of the eventual interference of absorbing and scattering properties of dissolved organic and particulate inorganic matters with these methods. The present study introduces a new method called Red tide Index (Rl), providing indices which behave as a good measure of detecting red tide algal blooms in high scattering and absorbing waters of the Korean South Sea and Yellow Sea. The effectiveness of this method in identifying and locating red tides is compared with the standard Ocean Chlorophyll 4 (OC4) bio-optical algorithm applied to SeaWiFS ocean imagery, acquired during two bloom episodes on 27 March 2002 and 28 September 2003. The result revealed that OC4 bio-optical algorithm falsely identifies red tide blooms in areas abundance in colored dissolved organic and particulate inorganic matter constituents associated with coastal areas, estuaries and river mouths, whereas red tide index provides improved capability of detecting, predicting and monitoring of these blooms in both clear and turbid waters.

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The Structure of Phytoplankton Community in the Hoeya River (Ulsan) (회야강(울산)의 식물플랑크톤 군집구조)

  • 최철만;배진현
    • Journal of Environmental Science International
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    • v.11 no.3
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    • pp.149-154
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    • 2002
  • This study was conducted to find the structure of phytoplankton community in the Hoeya river(Ulsan) from March 2000 to February 2001. The taxa of phytoplankton identified included 135 species, 5 divisions, 33 families and 82 genera. Among them, chrysophyta(diatoms) were 63 species(46.7%), chlorophyta(green algae) 47 species(34.8%), pyrrophyta(dinoflagellates) 13 species(9.6%), cyanophyta (cyanobacteria) 8 species(5.9%) and euglenophyta(euglenoids) 4 species(3.0%) respectively. Ecological important species is called frequently appearing species, red tide causative species, seawater species and pollution indicator. 22 species including Aulacoseira granulate were recorded frequently appearing species. 19 species including Ceratium furca were recorded as red tide causing species. And the pollution indicators were 33 species including Actinastrum hantzschii var. fluviatile. The highest standing crops were 3,103,441 cells/$\ell$ in August at the RW-1 and the lowest 1,245 cells/ $\ell$ in January at the RW-5. In the community analysis, the dominanance indices ranged from 0.34(October, RW-2) to 0.94(January, RW-1) and the diversity indices from 0.50(May, RW-2) to 2.57(September, RW-2). The saprobic indices were 2.43 in RW-1, 2.41 in RW-2, 2.375 in RW-3, 2.40 in RW-4, 2.43, in RW-5. Therefore, these areas were investigated "$\beta$-mesosaprobic". According to the similarity index among the stations, these areas were defined as residential district areas(RW-2 and RW-3), lower part of the dam (RW-1) and seawater areas(RW-4 and RW-5).

Reflections on the Significance of Post Offices as Indicators of the Evolution of the Red River Valley Settlement Systems in Louisiana (우편.체신업무체계에 근거한 루이지애나주 레드강유역의 취락발달 분석)

  • 홍금수
    • Journal of the Korean Geographical Society
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    • v.35 no.5
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    • pp.681-700
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    • 2000
  • 본 연구는 남북전쟁 이전 미국 루이지애나주 레드강 유역의 취락발달과정을 다루었다. 당시 프런티어에 들어선 우체국은 초기 기능지역의 결절점을 형성하였는데, 본 연구는 우체국의 업무기록에 수록된 통계자료를 바탕으로 우체국취락의 발달과정을 계층구조의 변화에 중점을 두고 접근하였다. 연구는 취락계층이 정보유통량에 비례한다는 가설을 전제로 수행하였다. 자료를 분석한 결과 크게 두 가지 사실을 확인하였는데, 초장기 취락발달이 배후지역으로의 확장을 특징으로 한 반면, 시대를 내려오면서 취락내부에 계층적 분화가 심화되고 있음을 알 수 있었다. 구조 변화의 주원인은 무엇보다 세계체제내에서 유럽과 미국 북동부 섬유산업의 원료로 이용되는 면화경제의 발달이었다.

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Aquatic Biodiversity of the 6 main lakes of Hanoi city and the necessity of its conservation

  • Yen Mai Dinh
    • 한국생태학회:학술대회논문집
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    • 1999.05a
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    • pp.43-54
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    • 1999
  • 1. Hanoi city was built up on the wetland landscape of the Red River delta therefore it has a network of many lakes and rivers. 2. The aquatic biodiversity (Macrophytes, Invertebrates, Fishes, Vertebrates) of the 6 main lakes (Ho Tay, Hoan Kiem, Bay Mau, Giang Vo, Dong Da, Thanh Nhan) are rich and diverse. It represents the patterns of Red River delta one's. Many rare and endangered species are found in these lakes Particularly a giant freshwater turtle species in Hoan Kiem lake. 3. All of these lakes are more or less polluted. Their environments are seriously degrading both in water quality and aquatic biodiversity. 4. Based on socio-economical and cultural role of these lakes of Hanoi city, it is very necessary to preserve and to restore their environments and aquatic biodiversity: water Pollution control, landscape planning, making roads around the lakes and erosion control for their banks, legislation measures, rational exploitation of aquatic biodiversity, restoration the artificial wetlands with macrophytes.

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Oxygen isotope study on the hydrothermal alteration in the Wolf River Batholith, Wisconsin in U.S.A

  • Kim, Sun-Joon
    • The Journal of the Petrological Society of Korea
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    • v.2 no.1
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    • pp.19-31
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    • 1993
  • Oxygen isotope compositions of whole rock and/or mineral separates (quartz and feldspar) have been determined for the granitic and related rocks from the Wolf River Batholith, Wisconsin. Hydrothermal alteration resulting in the decrease of ${\Delta}_{Q-F}$/ values was obaserved locally throughout the batholith. Feldspars of different colors (pink, gray and red) were separated whenever feasible and analyzed. Most red feldspars (An$_{10-30}$/) show the highest and constant ${\delta}^18O$/ values (9.3~10.0 permil) suggesting nearly complete isotope exchange with hydrothermal fluid. Based on ${\delta}^18O$/ values and the alteration temperatures (260~$350^{\circ}C$) estimated from fluid inclusion study, ${\delta}^18O$/ of fluid is calculated to be $5.0{\pm}1.4$ permil. Phanerozoic sedimentary formation water in Wisconsin is most likely the source of the fluid.

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A Study on the Cause and Improvement of the Red-Water Occurrence in Urban Stream (도심하천 내 적수발생 지점에 대한 원인검토 및 개선방안 연구)

  • Beomjin Eun;Jong Hwan Kim;Zi Yu Lin;Jeong Sook Heo;I Song Choi;Jong-Min Oh
    • Journal of Environmental Impact Assessment
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    • v.32 no.3
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    • pp.166-175
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    • 2023
  • This study aims to identify the cause of the red-water occurrence (the phenomenon of water being red) that occurs at some points and sections of rivers in Yongin City. As a result of conducting a preliminary investigation, total three sites were selected as the investigation point as it was found that the red-water occurrence continued. As a result of the investigation, it is judged that the cause of the red-water in Yongin-city river is due to the soil color and iron content of the region. JPS, SBS, and JJS sites all showed that the color of soil is mainly consist of reddish brown and red-yellow. The average Fe concentration was 13.75 mg/L, 10.85 mg/L, and 1.31 mg/L, for each sites, and considering that the Fe concentration in general river water was less than 0.5 mg/L, it was confirmed that the concentration was quite high. At the JPS and JJS points, the red-water occurrence occurred mainly in stagnant places, which is believed to be strengthened by the reaction of organic and microorganisms. In the case of SBS, the wateris red, but as a result of observing the actual color, it is judged that the iron component deposited in the pipe causes an optical illusion with a deep red color. In addition, it is believed that the iron concentration can be reduced to the general river water concentration range by removing the particulate iron component through a decrease of more than 95% as a result of filtering with glass fiber filter with particulate iron. As a result of this study, it is necessary to manage the river to maintain the flow, and it is believed that the occurrence of red-water at the survey point can be alleviated through uptake action through planting and agglomeration precipitation and agglomeration filtration methods for particulate iron treatment.