• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.5
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• pp.138-149
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• 2000

The purpose of this study is to evaluate Suwon stream naturalness Index(S.N.I). and tofind out stats, problems and opportunities of the Suwon stream by assessment standard. Assessment standard is mainly based on physical structure of stream environment. the purpose evaluating sectors and elements are physical form and structure restoration of stream. To find out assessment standard of stream naturalness index, conceptual frame of assessment standard has been established, for which four sections, for example, longitudinal section, lateral section, stream bottom structure and water environment, have been selected. Overall stream naturalness index of the Suwon stream has been distributed at 3rd to 4th grade, and 3.3 of assessment index and mode were 3rd grade respectively. stream naturalness index of each section was as follows: Longitudinal section accounted for 3.7in average to be 4th grade, lateral section did 3.8 to be 4th grade, and water environment did 2.4 to be 2nd grade. Analysis of assessment outcome of stream naturalness index has checked status, problems and opportunities of corresponding stream. Assessment of stream naturalness index of the study provides useful information for restoration of close-to-nature stream, and furthermore has its meaning in checking problems and opportunities of Suwon stream.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.4
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• pp.315-324
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• 2003

The purpose of this is to evaluate Hakui Stream Naturalness Index(S.N.I). and to find out stats, problems and opportunities of the Hakui stream by assessment standard. Assessment standard is mainly based on physical structure of stream environment. The purpose evaluating sectors and elements are physical form and structure restoration of stream. To find out assessment standard of stream naturalness index, conceptual frame of assessment standard has been established, for which four sections, for example, longitudinal section, lateral section, stream bottom structure and water environment, have been selected. Overall stream naturalness index of the Hakui stream has been distributed at 3rd to 4th grade, and its assessment index accounted for 3.2 to be 3rd grade, and its mode also did 3rd grade. Stream naturalness index of each section was as follows: Longitudinal section index accounted for 3.6 in average to be 4th grade, and later section index did 3.0 to be 3rd grade, and stream bottom structure index did 3.0 to be 3rd grade, and water environment index did 2.7 to be 3rd grade. Analysis of assessment outcome of stream naturalness index has checked status, Problems and opportunities of corresponding stream. Assessment of stream naturalness index of the study provides useful information for restoration of close-to-nature stream, and furthermore has its meaning in checking problems and opportunities of Hakui stream.

• Journal of Korean Society on Water Environment
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• v.27 no.2
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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.

• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.4 s.11
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• pp.131-143
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• 2003

The purpose of this study was to develop a new method for evaluation of stream naturalness in order to promote stream managers' understanding on importance of improving stream naturalness, and in order to appraise and prescribe for streams effectively in the process of ecological restoration of stream corridors. In order to analyze the evaluation method of stream naturalness and its applicability to streams, stream naturalness index(SNI) which has seven factors such as channel development, longitudinal profile, lateral section, stream bed structure, low flow channel structure, stream surroundings and water quality was suggested in this paper. For case studies, Bokha stream was selected for the evaluation of stream naturalness. At the Bokha stream, the scores of SNI factors were in range of $2.2{\sim}3.8$, and the average of SNI was 3.1, and the most frequent grade of SNI factors was grade 3. Among the 7 factors, the best was lateral section, and the worst was channel development. In this study, SNI grade can represent the characteristics of stream naturalness well and select the streams which will be restored, and can also decide the segment and the method of restoration for deteriorated streams.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.2
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• pp.73-81
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• 1997

The main purpose of this study was to develop a new method for evaluation of stream naturalness in order to appraise and prescribe for streams effectively in the process of ecological restoration of stream corridors. The results are as follows : 1) For this purpose six factors were selected on considering the spatial axes of stream corridor variation and total 20 descriptors about the physical structure were selected. 2) The calculation of S.N.I. for each segment was consisted of three steps, such as calculation of S.N.I.s of the individual descriptors, averaging all the descriptors's for each factor, and finally averaging the factors's for the Total S.N.I. 3) The evaluation unit was decided to be 100m size. The score system ranging 1~5 was adopted. Weighting parameters of factors were unified with each other. 4) A GIS model was adopted for classification, calculation, querying, analysing, and presenting S.N.I. information. And the format of S.N.I. maps including statistical graphs and other spatial watershed information was designed for the GIS odel. The naturalness of stream corridor was was investigated by the naturalness of habitat, and assessed by the descriptors focused on physical structure, therefore the S.N.I. can manifest prescriptions for restoration of the stream corridor. On the other hand because some evaluation factors such as water quality, water volume, fauna, flora, functions of stream exosystem has been excluded, S.N.I. could have some limits on representing the full aspects of stream naturalness. This evaluation method is hypothetical one, so it would be investigated through iterative applicatons.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.516-520
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• 2004

Stream Naturalness means the index of natural state in stream's ecosystem. The evaluation of stream naturalness can evaluate relatively the effect of environmental damages by human and to show how significantly current stream has been apart from its natural state. And it could be show what is the meaning of importance in stream's ecosystem by such distinctions and it Is done by showing the need how a large scale of action for restoration to be restored to natural state of stream system. In this study, a set of index for Stream Naturalness evaluation is proposed, which is referred to and modified problems with domestic and foreign study cases. This methodology is supposed to show well the characteristics of stream in Korea. A case study of Hong-Chun River shows how this methodology is applied to the Stream Naturalness evaluation. For improving the function of river which are water use and flood control and for preserving the function of inhabitation, the proposed methodology is expected to be used a index of direction for a environmental project related stream improvement by evaluation of ecologically sound function in streams.

• Journal of Environmental Impact Assessment
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• v.20 no.1
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• pp.61-69
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• 2011

Integrated stream naturalness based on abiotic and biotic factors were developed. Abiotic factors considered in this study were types of land use in the riparian area, river bank and high water bed streamside, revetment, bed substrate and artificial construction of streamside. Biotic factors included types of vegetation, assemblages of fish, macroinvertebrate, bird and mammal(Otter) in streams. The presence/absence of legal species and biological assessment index were also weighted as important parameters in this study. Scoring criteria selected for each matrix was five rating system; 1=poor, 2=moderate, 3=fair, 4=good, 5=excellent. Numerical ratings for the matrix were then summed. This resulted in a minimum score of 13 if all matrix at a site were poor, and a maximum score of 65 if all matrix were excellent. Five grade system from poor(I) to excellent condition(V) was employed. To verify its validity in natural environment, the evaluation system was applied to the Gapchun stream which is a test bed selected. Our result showed that stream naturalness of each reach was clearly distinguished by biotic and abiotic characteristics. Determination of correlation coefficient between abiotic and biotic factors was also high ($R^2=0.96$, p<0.05). In conclusion, assessment for stream naturalness reflecting abiotic and biotic factors was useful method representing stream integrated.

• Journal of Environmental Science International
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• v.23 no.1
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• pp.143-152
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• 2014

The results which are from naturalness assessment and visual assessment was examined to accomplish a classification, a conclusion, a comparison and an analysis. Also statistical test was examined to identify applicability of the survey to other rivers according to the result of visual assessment. As a result of naturalness assessment and visual assessment, evaluation rate of Geumho river is the highest rank of the grade as 2.5. Also t-test was examined to apply items of visual assessment at other rivers through differences in means of river naturalness rates from which visual assessment results. Most of differences in means of river naturalness rates are significant. Thus assessment criteria can be applied to other rivers to find out unique characteristics because each item has independent characteristics.

• Korean Journal of Ecology and Environment
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• v.41 no.4
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• pp.499-511
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• 2008

The major focus of this study is to evaluate a newly developed stream naturalness index system 'Habitat-riparian Indexing System (HIS).' There have been many studies that have assessed stream naturalness in order to provide information required for restoration. The results of these studies were enough for the purpose of the studies; however, the methodologies were limited especially with respect to rapid measurement and the representation of ecological habitats. Therefore, we derived crucial variables from a popularly utilized method and merged them with other criteria obtained from overseas approaches, resulting in the development of the HIS method. The stability of HIS was evaluated by comparing the results with the Stream Naturalness Index (SNI) of Cho (1997). We monitored 100 stream sites in the Nakdong River system using the two different methods for two sampling periods (spring and autumn), and the results were compared using statistical analyses. The determination coefficients between the index values from two methods were c.a. 0.6 for both seasons, and statistics revealed that HIS had a relatively higher stability, providing index values for stream environments. The results of this work suggest a possibility of the utility of HIS for other stream habitats.

• Journal of Environmental Impact Assessment
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• v.20 no.1
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• pp.1-11
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• 2011

This study was carried out to suggest the baseline data necessary for vegetation restoration at riverine wetland within stream corridor. We used the prevalence index for wetland assessment by applying the method of weighted averages with index values based on five hydrophyte indicator status as defined by estimated probability occurred in wetland. We selected near nature and urbanized reach of Gap and Yanghwa streams as experimental site. Although two sites have some different disturbance and characteristics of watershed, they showed that similarity of vegetation community including three dominant species - Salix koreensis, Phragmites communis, Miscanthus sacchariflorus - was very high. But in case of Yanghwa stream, various kinds of emergent plants along wetted condition were distinctly occurred, resulted from difference of hydrological regime and substrate, etc. Degree of naturalness of vegetation at the sampled areas indicated that near nature area of Gap stream and all area of Yanghwa stream were fitted as riverine wetland, while urbanized area of Gap stream has changed into upland condition. In conclusion assessment system using prevalence index would be considered an effective method for evaluating of natural states of riverine wetland, but further integrated consideration of physical, hydrological, and biological factors of stream process, and also with considering the difference between those qualitative data of vegetation community.