• Water Engineering Research
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• 제6권3호
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• pp.131-147
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• 2005

Today, a trend that tries to return the artificial space of a river to a natural one is expanding. But in Korea, which lies in the monsoon climate zone, rivers endure flood damage every year. Moreover, climatic change from global warming causes severe variations in precipitation patterns. Until recently, river restoration practices in Korea have followed partial restoration. These restorative treatments transformed artificial structures of the stream to natural ones and introduced natural vegetation by imitating natural or semi-natural streams. Treatment transformed the riparian structure and increased the diversity of micro-topography and vegetation. Furthermore, restoration recovered species composition, increased species diversity, and inhibited the establishment of exotic species. In particular, the Suip stream, which was left to its natural process for approximately 50 years, recovered its natural features almost completely through passive restoration. An urban stream, the Yangjae, and a rural stream, the Dongmoon, were restored partially by applying ecological principles. On the contrary, technological treatment applied to recover flood damage induced species composition far from the natural vegetation and decreased species diversity. Additionally, this treatment increased exotic species. The same results were found also in benthic invertebrate and fish fauna. The above-mentioned results reflect the importance of ecological considerations in river management.

• 환경정책연구
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• 제11권3호
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• pp.67-96
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• 2012

도심 하천복원사업의 정책적 방향을 도출하기 위한 기초연구로서, 이미 사업이 종료된 청계천 복원사업에 대한 사후 비용편익 항목과 분석방안을 제시하고자 한다. 사후 비용편익 항목을 도출하기 위해 사전 비용편익분석의 비용과 편익항목에 대하여 비판적으로 검토하였다. 검토의견과 예비타당성 표준지침, 비용편익분석 이론 등에 근거하여 사후 비용편익 분석방안을 제시하였다. 그 결과, 비용부문에는 보상비, 갈등조정비, 연구 및 홍보비, 감면받은 유지용수, 물 값 등이 포함되었다. 편익부문에는 환경개선편익 추정시 하천의 자연도 평가를 포함한 다속성 평가기법을 적용하도록 제안하였다. 이와 같은 사후 비용편익 항목과 분석방안이 제시됨으로써 도심 하천복원사업의 효율성이 증대되고, 하천복원의 의미에 더 부합되도록 사업을 평가할 수 있다.

• 한국환경복원기술학회지
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• 제6권2호
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• pp.11-20
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• 2003

This research was conducted to investigate the influences of the solifluction soil and amount of flow on the stream water quality of the Bukhansan National Park from March to october, 2002. The average pH of stream water was higher than that caused by solifluction soil. The average electrical conductivity of upstream water was about 2.1~2.8 times lower than that of downstream water. Linear regression analysis showed that pH and amount of anion($Cl^-$, ${NO_3}^-$, ${SO_4}^{2-}$) of stream water were very significantly correlated with those at the caused by solifluction soil. Structures for erosion control along both sides of stream channel should be designed in order not to influence upon solifluction soil and stream water quality.

• 한국물환경학회지
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• 제27권2호
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• pp.218-227
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• 2011

The objective approach for assessment of stream naturalness is an essential part of the stream restoration project. This study proposes the methodology for the assessment of stream naturalness considering physical, biological and chemical factors. Physical factors consists of riffle and pool, river bed material, bank protection, floodplain vegetation and levee materials; biological factors are benthic macroinvertebrate, KSI (Korean Saprobic Index), and IBI (Index of Biological Integrity) and chemical factors are pH, DO (dissolved oxygen), and TP (total phosphorus). This procedure is applied to the Mokgamcheon. As a result, the downstream of Mokgamcheon (zone I) needs the prompt improvement of stream naturalness, compared to the others (zone II and III). This evaluation technique will be an effective tool to quantify the stream naturalness and can be used to set the target of stream restoration project.

• 한국환경복원기술학회지
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• 제17권5호
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• pp.65-77
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• 2014

The ecosystem of Jaemin stream, flowing into the center of Gongju-si, had been damaged by low water quality and lack of water quantity of the steam. However, after applying the SSB (Sustainable Structured wetland Biotop) system to the flood plain and the upstream of Jaemin stream, the efficiency of ecological water purification and ecological restoration are as follows. Through the constant maintenance and monitoring from year 2009 to year 2013 after restorative design and construction the average influent concentration of BOD5 was 4.2 mg/L, and the average effluent concentration was 1.8 mg/L, reaching ecological water purification rate of 57%. As for the T-N, the average influent concentration was 9.983 mg/L, and the average effluent concentration was 6.303 mg/L, showing the rate of 37%. For the T-P, the average influent concentration was 0.198 mg/L, and the average effluent concentration was 0.098 mg/L, being the rate of 51%. The vegetation of Jaemin stream monitored for 2 years after the restoration was composed of 51 species in 28 families which show high ratio of planted native species. As for the animals in the site, 5 species in 3 families of reptiles and amphibians, 34 species of 23 families of birds, and 3 species in 2 families of mammals were monitored, indicating that the bio-diversity of the site has improved, as well.

• 한국환경복원기술학회지
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• 제21권2호
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• pp.13-26
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• 2018

The restoration of the impaired stream ecosystem is an important part of river policies in Ministry of Environment (MoE). However, the diagnosing the impairment sources of stream ecosystem has been omitted on the current river projects and policies. This phenomena lead the remaining impairment sources keep influencing on negative effects on streams. Hence, it is critical to construct a diagnosis system of impairment sources in order to increase the efficiency of various river restoration projects and policies. Moreover, it is also important to understand the relative impact of socio-economic factors of the impairment of stream ecosystems so as to build a domestic diagnosis system in place. Therefore, the study aims to analyse the relative effects of socio-economic factors which are the source of the stream ecosystem impairments through implementing the Analytic Hierarchy Process (AHP). In order to achieve the goal, a list of socio-economic factors influencing the stream health has been derived. On the basis of the derived causes list, AHP questionnaire were carried out to the experts of aquatic ecology. The study results could be implemented to analysing the relative influence of socio-economic impairment causes in domestic stream environments. In addition, more case study investigation is needed to cross-check if the derived impairment causes and weights are applied in the field as well as to develop more reliable indicators.

• Water Engineering Research
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• 제6권4호
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• pp.161-168
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• 2005

With characteristics of river continuum, stream ecosystems have diverse components and environments from upstream channel to estuarine area. Therefore, the habitat requirements and composition of conservative object should be well understood before applying any improvement measure. In this paper, the causes of stream habitat changes were first illustrated with the categories and principles of habitat restoration methods. The structural restoration techniques of fish habitat improvement utilized by the authors or one three-year research project starting at 1990 were then presented. Through the introductions on the project background, planning guidelines, structure design, and ecological evaluation, this paper tried to provide some effective examples of stream restoration practices that ecological expert was invited for cooperation and advising.

• 농업과학연구
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• 제38권2호
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• pp.315-324
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• 2011

Riparian vegetation distribution patterns and diversity relative to various fluvial geomorphic channel patterns, stream bank stabilization methods, and stream flow processes are described and interpreted for selected nature-friendly small stream bank protection of Goesan, central Korea. Idong Stream Pilot Project, which began in May 2003 and finished in December 2003, was selected to develop effective methods which was nature-friendly stream bank protection. The project aim to maintain or increase stream bank stabilization ecosystem goods and services while protecting downstream and stream bank ecosystem. A number of protecting methods which were a Flight of fieldstone, Vegetation block, Green river block, Stone net, Green environment block, Eco friendly cobble, Vegetation mat and Geo-green cell and Firefly block were applied on the bank of Idong stream. The stream sites have been monitored about vegetation conditions each method in 2007. We selected six points to separately investigate in left and right bank. The main purpose of this study was to find out suitable methods and to improve stream restoration techniques for ecosystem. On the stream bank, H environment block method (9.7) was the highest average of vegetation coverage and Firefly block method (3.87) was the lowest average in applied methods.

• 한국환경복원기술학회지
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• 제13권6호
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• pp.133-144
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• 2010

The objective of this planning proposal is to rehabilitate the urban stream which has been ecologically disturbed in the urban process. The experimental stream, Su-am stream located in Anyang City is typical urban stream in adjacent land use and the spatial condition. The stream in the watershed context, is the second tributary of Han River, in the Anyangcheon watershed. The Characteristics of the stream reach were analyzed by the river corridor survey. In the conceptual phase, Rehabilitation Programs were established based on the hydrological, ecological and spatial characteristics of the stream. Spatial zoning concept according to the characteristics of the stream and adjacent land use, was suggested 4 types of zoning; ecological preservation zone, natural landscape zone, neighborhood water-friendly zone and CBD water-friendly zone. Implementation Practices can be summarized as follow: For The longitudinal river continuum, some In-stream practices were suggested and implemented; such as channel alignment, step & pool, pool & riffle and low-flow channel bank. For latitudinal continuum and intimate spatial relationship between Sam-duk Park & Su-am stream, gentle sloped bank was planned and implemented. After stream improvement & ecological Implementation, follow-up monitoring and adaptive management programs will be a meaningful process for ecological rehabilitation.

• 환경영향평가
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• 제18권6호
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• pp.321-330
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• 2009

Spatiotemporal changes in the thermal environment in a large city, Seoul, Korea were analyzed using a thermal index, perceived temperature (PT), to standardize the weather conditions. PT is a standard index for the thermal balance of human beings in thermophysiological environment. For the analysis of PT, the data from long-term monitoring and intensive observations in and around the inner-city stream called 'Cheonggye' in Seoul, were compared with a reference data from the Seoul weather station. Long-term data were monitored by installing two automatic weather stations at 66m (S1) and 173m (S2) away from the center of the stream. Through the analysis of the data during the summer of 2006 and intensive observation periods, it was revealed that the stream's effects on the PT extended up to the distance of the S1 site. In winter, the increase of the PT between pre- and post-restoration was stronger at S1, which was nearer than S2 from the stream. These results suggest that PT can be used as an effective model in analyzing the changes of the thermal environment in relation with the changes of water surface areas.