• Journal of Korean Society on Water Environment
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• v.26 no.5
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• pp.850-859
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• 2010

Structure and succession of zooplankton community studied by hydraulic and ecological characteristics targeting the five lakes in the Han river system from March to December 2008. Results separated by river-type lake and lake-type lake depending on the type of hydraulic, Paldang lake and Cheongpyeong lake were river-type lake, while Chungju lake, Hoengseong lake and Doam lake was lake-type lake. The Paldang lake was a eutrophic lake, zooplankton community density and species number were the most among the five lakes. Relative dominance of the rotifera was the largest and the yearly first dominant species was a small cladocera Bosmina longirostris. The Cheongpyeong lake was a mesotrophic-eutrophic lake, hydraulic characteristics and zooplankton community changes were similar the Paldang lake. Relative dominance of the cladocera was the largest and the yearly first dominant species was a small cladocera Bosmina longirostris. The Chungju lake was a oligotrophic-mesotrophic lake, zooplankton community density was the least among the five lakes. Relative dominance of the copepoda was the largest and the yearly first dominant species was a large cladocera Daphnia galeata. The Hoengseong lake was a oligotrophic-mesotrophic lake, relative dominance of the rotifera was the largest and the yearly first dominant species was a small cladocera Bosmina longirostris. The Doam lake was a mesotrophic-eutrophic lake, zooplankton community density showed dramatic difference at the investigation time. Relative dominance of the rotifera was the largest and the yearly first dominant species was the copepoda Nauplius.

• Journal of Korean Society on Water Environment
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• v.25 no.6
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• pp.951-963
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• 2009

The community structure and ecological characteristics of fish community in Lake Paldang were investigated from May to September 2008. During the survey period, 53 species belonging to 13 families were collected. Dominant species was Squalidus japonicus coreanus representing 81.8% of total number and 25.7% of total biomass of collected fish and subdominant species was Lepomis macrochirus representing 3.3% of total number and 18.9% of total biomass of collected fish. There were 20 Korean endemic species (38% of collected species number) including Cottus koreanus and 4 exotic species (7.5%) including Micropterus salmoides. The similarity analysis of fish communities among water areas of Lake Paldang using UPGMA showed that fish community of North-Han River was similar to that of South-Han River area and was different from that of Gyeongan River area. Long-term variation of fish community from 1972 to present study in Lake Paldang showed decrease of the species numbers after dam construction until 1994, and gradual increase from 1996 to present study indicating the disturbance of lentic system by dam construction in the 1980s. The increase of species number in the late 2000s may results in part from the increase of survey sites of successive studies. L. macrochirus which was designated as a domestic ecosystem-disturbing alien species with wide food niche have shown more than 20% of relative abundance since 1996 indicating the adverse effect on not only fish community but also aquatic ecosystem food web of Lake Paldang.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.4
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• pp.91-98
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• 1997

At present, automated monitoring of water quality in Han river has been operated at each water treatment plant. But the automated measurement sites must be choosen newly because water source in Seoul move to the upper stream of Chamshil weir. In this study, automated monitoring sites in Han river were reviewed, and the proper sites for automated monitoring of water quality have been selected by Qual2E model, RMA model, water sampling guidline, Sanders' method and topograpical characteristics of Han river in order to resonable operate. 8 sites have been selected as follows: (1) the site of immediately after Paldang drainage (2) the left site and a right site of $Gu{\check{u}}i$ water intake (3) the left site and a right site at Noryangjin(Han river bridge) (4) the site between Shingok weir and Anyangchun confluence point(Hangju bridge) (5) the site of Chungryangchun downstream(existence) (6) the site of Tanchun downstream(existence) (7) the site of Anyangchun downstream(existence) (8) the site of Wangsukchun downstream. The results proposed resonable operating management of network and economical system built up.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.241-245
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• 2011

Small hydropower is one of the many types of new and renewable energy, which South Korea is planning to develop, as the country is abundant in endowed resources. In order to fully utilize small hydropower resources, there is a need for greater precision in quantifying small hydropower resources and establish an environment in which energy sources can be discovered using the small hydropower resource management system. This study has given greater precision to calculating annual electricity generation and installed capacity of small hydropower plants of Han river system by inquiring into average annual rainfall, basin area and runoff coefficient, which is anticipated to promote small hydropower resources utilization. Small hydropower resource management system was also established by additionally providing base information on quantified small hydropower resources and analysis function and small hydropower generator status, rivers, basin, rainfall gauging station, water level gauging station etc.. Small hydropower resource management system can be used gather basic information for positive applications of small hydropower energy nationwide.

• Water for future
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• v.18 no.1
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• pp.57-65
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• 1985

In recent years, an increment of river engineering activities and more intensive use of flood plain, the river geomorphology has attracted considerable attention owing to an extensive land reclamation. One of the important problems is the maintenance of river meanders and almost all natural rivers exhibit the tendency to be a meander. A statistical analysis is applied to typifying their shapes and the meander characteristics are analyzed by channel model of line generalization algorithm in this study. This method is applied to Han River System. The results show that the variance of curvature is a better index to describe the meander intensity and the kurtosis is a good index to characterize the total lengh of the straight sections for a given reach. The channel model of line generalization algorithm gives good results in analysis of meander characteristics.

• Journal of Plant Biology
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• v.12 no.3
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• pp.35-41
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• 1969

To clarify the types of brackish region of the Han River Estuary, this research was carried out, and the results obtained on the basis of salinities and phytoplankton are as follows: 1. Geomorphologically, the Han River Estuary is the drowned river valley type. 2. According to the Venice System, the estuarine extent is defined from the lower point of Jollyu-ri to Palmi Island. As a whole the estuarine region is mixo-haline including parts from oligo-haline to poly-haline. 3. In standpont of phytoplankton frequency, the frequency of fresh-water species is high in the upper region of estuary and that of marine species is high in the lower region. The rate of frequency of fresh-water species is inversely proportionate to that of marine species. The area mixedby marine and fresh-water species over estuarine boundary. 4. The frequency of some typical brackish species is very low and almost similar in the whole region.

• Spatial Information Research
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• v.8 no.1
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• pp.131-140
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• 2000

The systematic data management system in the area of river flow analysis has not yet constructed, even though the need is evident due to the complicated process of tremendous input/output data in the modeling study and the importance of visualization of spatial flow variation. The objectives of this study are to suggest the method for constructing the NGIS-based river database based on contour, river, elevation, boundary layers and river cross sections and to provide the algorithm for interpolating equi-distance river cross section points. The selected study area is the main Han River starting from Paldang dam site to Indogyo bridge. The constructed database will be useful for the scientific water flow management system in the study area.

• Current Research on Agriculture and Life Sciences
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• v.17
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• pp.31-38
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• 1999

Trend of some hydrologic features such as precipitation, runoff and reservoir storage rates in the five great river systems of Han, Nakdong, Keum, Yeongsan and Seomjin river watershed areas were surveyed and analysed. The sample period of Sept. 1994 to Aug. 1998 (four years) was chracterized by unusual climatic features such as El Nino, La Nina and areal terrible storms. And also average values of rainfall and runoff of the priod of 1961 to 1990 (30 years) were surveyed and analysed compared with the sample preiod events for the same river systems. In case of the monthly mean rainfall of the sample period (Sept. 1994 to Aug. 1998 : 48 months) in the five great river systems, 20 months, 19 months, 20 months, 21 months and 18 months in the Han, Nakdong, Keum, Yeongsan and Seomjin river system respectively were higher than monthly average rainfall records of the 30 year records. For the monthly runoff in the same river systems, 7 months, 9 months, 7 months, 11 months and 11 month in the Han, Nakdong, Keum, Yeongsan and Seomjin river systems respectively were higher than the monthly average runoff of the period of 30 years. For the storage rates, most of the dams in the Han river systems were highly stored through the year continuously and Paldang dam was specially higher than the other dams in the same river system. And most of the dams in the other river systems were stored irregularly but getting much better than early time during the 48 months. And special climatic features were not found during the sample period of 48 months, Sept. 1994 to Aug. 1998.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.1
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• pp.177-185
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• 2009

In this study, we developed the program to calculate the corrosion evaluation index for examining the corrosivity of raw water. When it was applied to the Han river and Nakdong river system, sulfuric acid ion, which accelerated corrosion, was higher in Nakdong river system than Han river system while calcium and hardness, which restrained corrosion, was the same way. Summarization of the LI and CCPP calculation result by the developed corrosion evaluation model showed that water quality of Han river system had strong tendency to corrode (is strongly corrosive). Moreover, this study evaluated the corrosivity of calcium carbonate saturation index by adding the chemicals to tap water. Saturation status was maintained in the order of $Ca(OH)_2$ > NaOH > ${Na_2}{CO_3}$ > $CaCO_3$ in the case of LI and RI.

• Journal of Korea Water Resources Association
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• v.31 no.4
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• pp.415-427
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• 1998

FIAS (Flood Inundation Analysis System) using Arc/Info is developed and applied to the South Han River basin. The DWOPER model is revised and expanded to handle simultaneous multiple overtopping and/or breaking and to estimate the inundation depth and extents. The model is applied to an actual levee overtopping case, which occurred on August 23~27, 1995 in the South Han River. Stage hydrographs inside and outside of the levee are compared, then inundated discharges from overbank spilling are computed. The Graphic User Interface is developed with AML(Arc/Info Macro Language). Two-and three-dimensional inundation maps by Arc/Info are presented. The computed inundation extends agree with observations in terms of inundation depth and flooded area. Keywords : River, Floodwave, Flood Inundation, Geographic Information System.