• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.4
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• pp.24-36
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• 2008

The essence of a natural stream restoration project is providing habitats for various creatures in terms of the stream's environmental function. This research suggests the problems of natural stream restoration project by studying streams in terms of habitats for creatures and reviewing the national and international cases on existing natural stream restoration project. As a solution for the above, this research suggests a preservation method for biotope of upper stream areas focusing on the fish biotope area considering the ecological characteristics and preservation value of the respective stream so that the stream can be preserved as habitats for creatures. The research was carried out on Cheonglimli Baekcheon region which is an upper stream area of Buan-Dam located in the public park in Byunsanbando, Buangoon, Jeonlabookdo. We suggest the preservation method based on the habitat environment and keystone species of fish. The habitat environment evaluation was carried out mainly being divided into three groups namely, habitats and surrounding environment, reservoir's features and fish way and the diversity of fish. By improving the problematic elements discovered through such evaluation, it tries to improve the biotope of the stream and continuously preserve the stream. In addition, in order to restore the stream as habitats for various creatures, this research suggests to select keystone species which are suitable for the stream environment and restore the habitats based on the keystone species rather than restoring habitats for all species. Fish not only plays the role of a consumer of Epilithic algae and water beetles but also plays an important ecological role as a food for birds or small mammalia. If such ecologically important biotope for fish is preserved, the ecological environment of the stream will be maintained more stably.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.558-564
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• 1998

Flow rate, watertable and selected water quality of 2 small rural streams and 6 observation well located in Kangwon-do, Korea, were monitored land use of the watersheds was investigated to describe the trend of stream water quality for 2 years and groundwater quality for 1 year. Water qualities were analyzed with respect to BOD, SS, T-N, Nitrate, T-P and E-coli. Stream water quality and gorundwater quality directly concerned with the amount of rainfall and paddy fields. but water quality of watersheds is existed with other factor. Therefore, We have to continued monitoring and developing the best management practice.

• Proceedings of the Korea Water Resources Association Conference
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• 1983.07a
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• pp.78-79
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• 1983

It is well known that small amplitude wave theory, a first approximation to the complete theoretical description of wave behavior, yields a maximum investment in mathematical endeavor. But, if the wave amplitude is large, the small amplitude considerations are not valid, and finite amplitude wave theory which retains higher-order terms to obtain an accurate representation of the wave motion is numercal theory. The Stream function wave theory, one of the numerical methods, was developed by Dean for use with asymmetric measured wave profiles and with symmetric theoretical wave profiles. Dalrymple later improved the comjputational procedure by adding two Lagrangian constraints so that more efficient convergence of the iterative numerical method to a specified wave heigh and to a zero mean free surface displacement resulted. This paper introduces in details the Dean and Darlymple Stream Function Method in case of the symmetric theoretical wave, because in design purposes, wave height and wave period are given.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.1
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• pp.55-75
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• 2017

The purpose of this study is to present the basic data for restoration of physical stream environment by analyzing habitat variables because habitat environment is changed due to the construction of waterfront space in urban streams. Assessment results of 10 habitat variables(three divisions) were almost same as optimal condition, in the reach of reference stream where there are no stream crossing structures and channel alteration. Assessment results of reaches in urban rivers, where streams were improved on water-friendly recreation activities, appeared to be marginal condition. Because habitat environment got worse due to stream improvement works such as construction of weir for water landscape, stepping stones for walking, low water revetment and high water revetment, and high water channel. In addition, in the case of mid gradient stream, the frequency of riffles was small or not existed because the intervals of the river crossing structures was short. In the case of mild stream types, the diversity of the pool was damaged due to the deposition of sludge in the upstream pool of weir and the installation of low water revetment.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.6
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• pp.162-167
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• 2006

The urban stream includes the channel and sandbars. The sandbar plays a key role in the riparian ecosystem. For birds and insects the sandbar offers a small strip of habitat and fish and other fauna feed in the boundary of sandbar where eddies occur. So, it is important habitat and source for the flow of energy, matter and organisms through the landscape and act as ecotone between the terrestrial and stream corridors. However, the sandbar changes continuously by the natural process. Thus, it is necessary to measure the shape and area of the sandbar accurately for the efficient urban stream management for the amenity of urban residents and stream protection. The study site is Yangjae Stream where the first natural-style urban stream restoration projected was impelemented by the support of Ministry of Education in Korea. The measurement was taken by the beacon Differential Global Positioning System (DGPS) and the data were stored and analyzed using ArcView Geographic Information System (GIS) program. Therefore, the purpose of this study is to measure the change of sandbars in the urban stream after concentrated stormwater during summer.

• Journal of Environmental Science International
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• v.14 no.8
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• pp.739-748
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• 2005

The purpose of this study is to analyze seasonal changes in structure and landscape of Gongji stream corridor in Chuncheon, and to suggest some guidelines to contribute to creating a desirable close-to- nature stream. The study seasonally surveyed floodplain and revetment conditions, channel micro-topography, streamflow level and velocity, and vegetational cover. Flooding, water level, and vegetation were major factors of affecting seasonal changes in streambed structure and stream landscape. Small sand bars and islands were considerably disturbed by flooding and water level change. However, large islands and sand bars in the upper and middle section of the study stream remained or reappeared even after flooding. Flooding also tended to repeat channel sedimentation at the same spot. Controlling water volume of the Euiam Lake, which is adjacent to the study stream, caused higher water level downstream in the dry seasons. The majority of vegetation in sand bars and islands was washed away by the floods. Vehicle passing, crop cultivation, and ball game were other elements which disturbed vegetation in the floodplain. Creating a close-to-nature stream should reflect micro-topographical changes of channel by flooding, prevent improper vehicle entry and human use, and remove concrete material in the revetment and floodplain.

• Journal of Korean Society of Rural Planning
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• v.26 no.1
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• pp.89-99
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• 2020

This study was conducted as a basic research to create a sound and vital ecological environment in the city compared to the appearance characteristics of Gap stream(G-stream), which are the main stream of Banseok stream(B-stream), by analyzing the characteristics of waterbirds, including Wild Spot-billed Duck (S-Duck), that live in B-stream built as ecological stream. The waterbird survey was conducted by the line census for 3.2km, Jukdong-bridge to Jamiseon-bridge, from January to August 2018. The analysis of the survey was conducted with Relative species density(RD) of the emerging waterbird species, the Species diversity and Density Per Unit area for 100㎡(DPU). The waterbird survey results of B-stream was conducted 65 times. The five types of water birds that appeared during the survey were Spot-billed Duck(Anas poecilorhyncha), Teal(Anas crecca), Little Egret(Egretta garzetta), Great Egret(Egretta alba), and Grey Heron(Ardea cinerea). As a result, for S-Duck at B-stream, RD was 89.9%, monthly species diversity was simple as 0.3801 in January, 0.5943 in February and 0.3501 in August. The DPU of the S-Duck was 0.165/100㎡ in the B-Stream survey section which was 4.9 times higher than the main stream section, G-stream. The non-freezing zone of the city's small stream is expected to play an important role as a winter stop for wild birds such as S-Duck during the freezing period of the huge stream. For this reason, considering the ecological characteristics of wild waterbirds such as S-Duck when creating ecological stream, a: space and linear selection of waterways which can minimize the impact of natural enemy and increasing the number of walkers, b: management water-friendly plants in the low flow channel, c: arrangement walking-bicycle road will be necessary.

• Journal of Korea Water Resources Association
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• v.33 no.1
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• pp.73-85
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• 2000

A water quality model was developed for small stream at a upland agricultural watershed. A control volume method was employed to digest the severe variability of stream shape, water quality and discharge at small streams. We estimated optimum reaction coefficients and model structure using a random number generation technique. The index of agreement and coefficient of efficiency were introduced for the model calibration criterion. As the result, the reliability of model parameter estimation could be improved. The applicability of model was tested by a set of sampling results at Yongduckchun in Kimhae. The variability of water quality reaction coefficient was explored through the observed data and using the developed model. model.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.341-351
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• 2015

This study is to select the areas to ensure stream space or to implement flood defence measures according to flood frequencies by classifying the stream segment using river bed slope in Mangyeong river. The analysis result for each stream segment showed that the variation of flood inundation area was small in upper stream catchment. But in the lower stream area, the inundation area became larger greatly according to the increase of flood return period. This study classified the catchment of each steam segment as the region of ensuring stream space (ESS), below 10% residential area ratio, and the region of reinforcing flood defence (RFD), over 10% residential area ratio. The analysis results showed that the lower stream area included more RFD regions than upper stream area, and the upper stream area included more ESS regions than lower stream area. In future study, the regions stream spaces can be ensured will be analyzed considering the past stream morphology and the positions of wetlands.

• Journal of Korea Water Resources Association
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• v.34 no.5
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• pp.561-566
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• 2001

This study is the analysis of hydraulic characteristic for stream diversion reach by numerical model test. Through it we can provide the basis data in flood, and in grasping stream flow characteristics. Analysis of hydraulic characteristics in Seoknam stream were implemented by using computer model HEC-RAS(one-dimensional model) and RMA2(two-dimensional finite element model). As a result we became to known that RMA2 to simulate left, main channel, right in stream is more effective method in analysing flow in channel bends, steep slope, complex bed form effect stream flow characteristics, than HEC-RAS.