• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.469-472
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• 2002

This study was conducted to show how to manage the water quality of Kyung-an river. The water quality and hydrologic data were obtained at the main river and branch streams in Marc $h{\sim}April$ 1998. First of all, we surveyed the contribution of branches for the pollution of water quality at Kyung-an river. It was in order of Kongiam(25.5%)>Yong-in Pollutant Treatment Complex (15.26%)^gt;Shin-won(13.99%)>Buen(11.86%)>Yangji(8.68%)>Yooun(7.43%)>Kwang-ju Pollution Treatment Complex(5.50%)>Osan(5.04%). The hydrological model using mass balance and BOD reduction formula suggested that if the quality of water Yoo-un and Shinn-won stream (branch streams of Kyung-an River) which is lowest in the basin is controlled adequately and outlet water from Yong-in pollutant treatment complex is adequately treated, the quality of Kyung-an river will be improved by 90% compared to current level.

• Environmental Engineering Research
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• v.15 no.2
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• pp.117-121
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• 2010

The continual extraction and indiscriminante use of groundwater for residential sectors could cause a decrease in the groundwater level in Para$\tilde{n}$aque river and Las Para$\tilde{n}$aque City; and allows saltwater to penetrate into the aquifer due to the proximity of Manila Bay. This study models the present condition and extent of saltwater intrusion in the aquifer bounded by Para$\tilde{n}$aque river River and Manila Bay. The model is simulated using a 3D finite element modeling software (FEMWATER) that is capable of modeling the groundwater flow condition in the aquifer. Moreover, the model can also be used to predict the future condition of the aquifer for better groundwater management. This study aims to raise public awareness of the extent of the problem and the possible side effects incurred. The model will serve as a basis for further studies on remediation techniques and saltwater intrusion control in the coastal aquifer of Para$\tilde{n}$aque river City.

• Journal of Environmental Science International
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• v.11 no.12
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• pp.1281-1289
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• 2002

This study was conducted to evaluate water quality in the Keum River using multivariate analysis. The analysis data in Keum river made use of surveyed data by the ministry of environment from January 1994 to December 2001. Thirteen water quality parameter were determined on each sample. The results was summarized as follow; Water quality in the Keum River could be explained up to 71.39% by four factors which were included in loading of organic matter and nutrients by the tributaries (32.88%), seasonal variation (16.09%), loading of pathogenic bacteria by domestic sewage of Gapcheon (13.39%) and internal metabolism in estuary as lakes(9.03%). For spatial variation of factor score, four group was classified by each factor characterization. Station 1 and 2 was influenced by Daechung dam, station 3 was affected by domestic sewage of Gapcheon, station 10~12 was affected by estuary dyke and the rest station. The result of cluster analysis by station was classified into four group that has different water quality characteristics. In monthly cluster analysis, three group was classified according to seasonal characteristic. Also, in yearly cluster analysis, three group was classified. It is necessary to control the pollutant loadings by Gapcheon inflow domestic sewage in Daejeon city for the sake of water quality management of Keum river.

• KIEAE Journal
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• v.10 no.6
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• pp.47-54
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• 2010

The significant aim of this research is to suggest the applicable data for the future urban ecological restoration of rivers' activity and the direction of the future eco-experience program found by analyzing the state and progress of the restoration of the river ecological experience program. For this purpose, we researched the eco-experience program's outline and details of its operation and method from six rivers among all of the rivers going through restoration. We also carried out telephone interviews and in-depth interviews with the office staff that takes care about each river at the district office to investigate the specific details not revealed by our analysis, the number of operations, and the number of participants. We compared the number of operations to the number of participants and the frequency of participation of each river in a year. As a result, they have revealed that the participants of the eco-experience program ranged in variety including local students, families, and local citizens as a whole. Also the intimate observation and experience with nature gave the participants a better understanding of the ecosystem. In addition, it is revealed that the cheonggye river goes through its own standard of strict inspections and management daily. It is quite easy to notice that the cheonggye river shows a higher level of participation and operating activity than other rivers.

• Korean Journal of Remote Sensing
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• v.22 no.5
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• pp.421-425
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• 2006

It can be important framework data to monitor the change of land-use pattern of river boundary in design and management of river. This study analyzed the change of land-use pattern of Gab and Yudeung River using time-series aerial images. To do this, we carried out radiation and geometric correction of image, and estimated land-use changes in inland and floodplain. As the analysis of inland, the ratio of residential, commercial, industrial, educational and public area, that is urbanized element, increases, but that of agricultural area shows a decline on the basis of 1990. Also, Minimum Distance Method, which is a kind of supervised classification method, is applied to extract water-body and sand bar layer in floodplain. As the analysis of land-use, the ratio of level-upped riverside land and water-body increases, but that of sand bar decreases. These time-series land use information can be important decision making data to evaluate the urbanization of river boundary, and especially it gives us goodness in river development project such as the composition of ecological habitat.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.6
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• pp.85-95
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• 2015

Recent years, nationwide projects for ecological restoration are implemented with emerging issues on the stream ecosystem. In order to enhance effectiveness of the ecosystem restoration and reduce negative impact, the appraisal of effectiveness through the follow-up monitoring and the adaptive management process are executed in consecutive phase. In this study, planning phase, monitoring and adaptive management in Hakui stream which is part of An Yang stream restoration project is introduced as representative ongoing case of effective adaptive management. The aim of this study is to verify the adaptive management process and suggest direction of effective restoration. Restoration project of Hakui stream resulted in increasing number and diversity of species (vegetation, fish, bird, invertbrates, amphibian and reptilia) according to monitoring from 2004 to 2013, and enhancing natural river landscape by evaluation of river naturalness among 2001(before restoration), 2007 (after), 2015 (recent). However, excessive vegetation expansion or sediment deposition on channel over time caused unexpected results such as terrestrialization or degradation of habitats. Adaptive management action such as removing disturbance species (Humulus japonicus)(2007), coppicing willow (2007), release of march snail (2007), creation of wetland (2014) were implemented based on monitoring results. And then appraisal of management action was discussed.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.2
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• pp.174-189
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• 2015

The objective of this study was to reconstruct spatial information using the results of the investigation and evaluation of the health of the living organisms, habitat, and water quality at the investigation points for the aquatic ecosystem health of the Nakdong River basin, to support the rational decision making of the aquatic ecosystem preservation and restoration policies of the Nakdong River basin using spatial analysis techniques, and to present efficient management methods. To analyze the aquatic ecosystem health of the Nakdong River basin, punctiform data were constructed based on the position information of each point with the aquatic ecosystem health investigation and evaluation results of 250 investigation sections. To apply the spatial analysis technique, the data need to be reconstructed into areal data. For this purpose, spatial influence and trends were analyzed using the Kriging interpolation(ArcGIS 10.1, Geostatistical Analysis), and were reconstructed into areal data. To analyze the spatial distribution characteristics of the Nakdong River basin health based on these analytical results, hotspot(Getis-Ord Gi, $G^*_i$), LISA(Local Indicator of Spatial Association), and standard deviational ellipse analyses were used. The hotspot analysis results showed that the hotspot basins of the biotic indices(TDI, BMI, FAI) were the Andong Dam upstream, Wangpicheon, and the Imha Dam basin, and that the health grades of their biotic indices were good. The coldspot basins were Nakdong River Namhae, the Nakdong River mouth, and the Suyeong River basin. The LISA analysis results showed that the exceptional areas were Gahwacheon, the Hapcheon Dam, and the Yeong River upstream basin. These areas had high bio-health indices, but their surrounding basins were low and required management for aquatic ecosystem health. The hotspot basins of the physicochemical factor(BOD) were the Nakdong River downstream basin, Suyeong River, Hoeya River, and the Nakdong River Namhae basin, whereas the coldspot basins were the upstream basins of the Nakdong River tributaries, including Andong Dam, Imha Dam, and Yeong River. The hotspots of the habitat and riverside environment factor(HRI) were different from the hotspots and coldspots of each factor in the LISA analysis results. In general, the habitat and riverside environment of the Nakdong River mainstream and tributaries, including the Nakdong river upstream, Andong Dam, Imha Dam, and the Hapcheon Dam basin, had good health. The coldspot basins of the habitat and riverside environment also showed low health indices of the biotic indices and physicochemical factors, thus requiring management of the habitat and riverside environment. As a result of the time-series analysis with a standard deviation ellipsoid, the areas with good aquatic ecosystem health of the organisms, habitat, and riverside environment showed a tendency to move northward, and the BOD results showed different directions and concentrations by the year of investigation. These aquatic ecosystem health analysis results can provide not only the health management information for each investigation spot but also information for managing the aquatic ecosystem in the catchment unit for the working research staff as well as for the water environment researchers in the future, based on spatial information.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.772-773
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• 2005

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.84-85
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• 2005

• Journal of the Korean association of regional geographers
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• v.10 no.4
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• pp.757-774
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• 2004

This paper is to reclassify systematically the functions of urban river: that is, water supply, land management, transportation and energy source as social and economic function; formation of geomorphic surface, water-side landscape, community constitution and boundary and separation between regions as spatial function; and drainage of waste water, purification, habitation, and weather regulation as ecological function. On the basis of this reclassification, it can be argued that the socio-economic functions (eg. water supply) of the river among the functions of the river have been strongly mobilized in the process of modernization, while the spatial function and ecological function of urban river have been ignored. The Kumho river which flows through Daegu and the adjacent area has made a great contribution to the modem development process of the river basin area, but as a result of a selective development of a specific function of the river, that is the social and economic function, it now suffers from the lack of instream flow and is deprived of its original functions with the water pollution and degradation. Moreover the Daegu region seems no longer possible to develop on the dependence of the river. In order to overcome this kind of social and environmental crisis, this paper is to suggest both some principles and main evaluating indicators to restore the original and comprehensive functions of the river, and important measures to make the co-evolution of the city and the river possible.