• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.4
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• pp.15-26
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• 2013

In recent years, river maintenance projects using natural methods have been continuously implemented in urban areas and methods emphasizing ecology are being developed and constructed in revetment areas. However, there is insufficient technical review on the hydraulic stability of those revetment methods during the event of flood. Therefore, a hydraulic analysis is necessary for the stream where revetments are applied. This study was conducted to develop an objective test method for the hydraulic stability of green revetment media. For this purpose, hydraulic model tests were performed for the green base materials for revetments. Tests were conducted using experimental devices for the hydraulic model which were installed to simulate the rapid current during the flood. Loss of soil by the hydraulic condition was compared and analyzed with that of dry green revetment media, and the evaluations were made on the corrosion resistance, tractive force, and contractile force. Test results showed that green revetment media had higher corrosion resistance in non-vegetation condition compared to dry green revetment media, and the loss of base materials by the rooting of vegetation showed significant reduction by the vegetation. In addition, results of the allowable tractive force of the base material indicated it is relatively stable in vegetation condition but scouring can occur in non-vegetation condition. Therefore, the development of vegetation in revetment areas is anticipated to be effective for the stability of revetment areas by reducing external forces interacting with the corrosion resistance and stream bank. The green revetment media in expected to contribute to the stability of revetment areas.

• Korean Journal of Environment and Ecology
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• v.22 no.3
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• pp.268-279
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• 2008

This study is aimed at typifying the crossing structure and inquiring into the characteristics of vegetation distribution by type targeting Dorimcheon(stream), Banghakcheon(stream), Seongnaecheon(stream) and some sections of Yangjaecheon(stream) in Seoul through the establishment of basic data for restoring vegetation in urban stream. This research classified the crossing structure into 56 slope types and 31 vertical types in combination with the three items, such as bank slope(vertical style, slope style) of bank, absence or presence of waterside, and revetment structure. This research derived nine slope types including SB1 (revetment of low water level-revetment with vegetation, and revetment of high water level-nature riverside) including SG5(revetment of low water-concrete, and revetment of high water level-riprap work), and three vertical types, such as VH4(bank revetment-wet masonry), and VH7(bank revetment - concrete )from the target survey areas. Among these, both revetment of low water level and high water level were found to be distributed on the longest section as the type of SG7 and VG7 structured in concrete. As a result of inquiry and analysis of micro topography structure and vegetation structure of eight major types, this research could find out the influence of crossing structure on plant vegetation according to the characteristic by typified item, but there appeared no distinct characteristic of vegetation distribution by crossing structure.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.97-102
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• 2003

This study was carried out to understand the variation of bird community by eco-park development of urban stream, Yangjae stream, Seoul, from Jan. 1996 to Dec. 2001. After the development, slight change in the bird community happened; for example, the number of species increased(r²=0.729, p<0.05), but there was not any variation in the total number of birds(r²=0.050, p>0.05). Especially, the number of individuals in herons and ducks rose. We suggest that the change as caused by restoration of low revetment vegetation and artificial pond vegetation in flood plain. However, the number of sandpipers, plovers and wagtails inhabiting on the sands and gravels in stream fell down. It seems that it would be caused by construction of bicycle path on the flood plain. The number of songbirds was tended to go down to 2000, but increased in 2001. The decrease of songbirds might be attributed to irregular removals of bush. We suggested that riparian vegetation restoration and artificial ponds positively affected birds inhabitation, but bicycle path and irregular elimination of a bush negatively affected.

• Korean Journal of Environment and Ecology
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• v.11 no.2
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• pp.210-213
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• 1997

This study for development of close-to nature revetment techniques is conducted to rehabilitate disturbed stream ecosystem. For this objective, the experimental reach as on-site dimonstrated research was set up in Hakyoul, the Yangjaech'on from Oct. 1995 to Nov. 1996. Special emphasis on the developing process of the design of revetments was given to geomorphic character of 3 types of low flow channel bank: point bar, attack point and shallow bay. Each revetment was developed with the consideration on revegetation of emergent plants. And designed techniques were applied to the experimental reach, and were evaluated with monitoring for 1 year. As a result of the process, the experiment suggested ecological alternatives to enhance technical feasibility and to replace the conventional river-work.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.2
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• pp.112-129
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• 2012

The aim of this study was to provide basic data in managing the project that was carried out on Bulgwangcheon in a nature-friendly way to improve the conditions around the areas, which was brought to completion in 2002, based on changes in ecological characteristics. For this propose, this study examined documents related to the project, compared physical and enviromnental changes before and after the project was conducted and analyzed changes in the stream ecosystem. The result showed that in areas that effluent water was often observed, especially when it rained, the river wall was washed away and vegetation was found damaged. As for actual vegetation, this study compared planting coverage of each section of the research area and actual vegetation charts. The results indicated that Lespedeza spp., Aster koraiensis among mixed seeds that were planted in the reservoir path were almost swept away while Festuca arundinacea dominated the areas. Phragmites communis, Miscanthus sacchariflorns and Salix gracilistyla which had been planted in a small number were also almost washed out though a small number of them were left to form a colony. After examining the topography and structure of the plant community, this study found that areas where mixed seed were planted had changed into two types of vegetation: First type of area is dominated by P and R which are usually raised in apron with abundant floating particles. The second type of area is dominated by dry gramineous plant such as F and A. Areas around low flow channel where Phragmites communis, Miscanthus sacchariflorus and Salix gracilistyla planting construction method is applied was washed away with the width of low flow channel reduced. Though P, M and S formed a small community in some areas around the low flow area, they were in small number and in composition of simple plant species. Two ways were suggested in this study to manage the stream in an ecological way. First, adequate revetment construction methods should be applied by monitoring the flow of the stream as well as considering the flood control of urban streams. Second, target vegetation communities that are suitable for the environment of the stream should be chosen and be plantedconstantly with high density. At the same time, ornamental native plants shouldn't be planted as they have been and disturbing vegetation should be removed.

• Ecology and Resilient Infrastructure
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• v.2 no.1
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• pp.99-104
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• 2015

Topsoil including numerous soil seedbanks has been known to be a valuable material for ecological restoration. There is a lack of specific study for its utilization in the field of stream restoration. This study conducted a revaluation of the value of topsoil as a material for stream restoration. Furthermore, an ecological technique using topsoil was applied in an improvement project of a stream environment at the Hwanggujicheon Stream in Korea. Stockpiling and spreading topsoil was specifically applied to the revegetation of a low slope revetment and a high flow plain. The result of this application showed that topsoil played an integral role in eco-friendly restoration in terms of ecological, flood control, economic, and constructional aspects. In conclusion, this study's findings suggest that topsoil is a suitable candidate material for stream restoration.