• Journal of Environmental Science International
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• v.12 no.3
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• pp.247-255
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• 2003

Forest management starts from forest road facility, which is designated as generation source of muddy water in mountain stream during initial stage of establishment. Therefore, this study reviewed the effect of suspended sediment generated in forest road surface on the muddy water in mountain stream with respect to marsh area of forest. As a result, characteristics of outflow of suspended sediment was understood, and it was judged that generation of suspended sediment due to establishment of forest road is diluted by mountain stream this charged from drainage area so as to have small effect on muddy water in total mountain stream.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.644-653
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• 2018

Landslides occur frequently due to the effects of heavy rainfall and typhoons caused by climate change. Erosion control measures are needed to effectively prevent landslide damage. In order to improve their efficiency, it is necessary to quantitatively measure the sediment discharge from the mountain stream. In this study, a load cell sensor was installed in a mountain stream and the measured values were compared according to the applicability and load test type in the mountain stream. The result of the load test showed that the effect of the loading type (load test 1, 2) was low at average (loadings) of 0.4kgf and 0.6kgf at sites 1 and 2, respectively. The load factor was also derived by regression analysis to increase the accuracy of the measured values. According to the results of the load factor (normalized) to the load-cell measurement value, the output value increased by 14.8% and 24.6% in sites 1 and 2, respectively, and was calculated to be similar to the reference value. The load cell sensor enabled us to quantitatively estimate the amount of sediment discharge in the mountain stream through time series analysis with the water level and rainfall information. If the monitoring is carried out for a long time, it can be used to find the sediment discharge mechanism for the mountain stream. In addition, applying sensors such as load-cells to a mountain stream is expected to contribute to the development of related industries, such as the manufacturing of measurement sensors.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.16-27
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• 2020

This study presented a plan for the establishment of conservation areas and the ecological management of those areas in the stream based on the Marxan with Zones Program for a Jungrangcheon Stream in downtown Seoul. The application of the Marxan with Zones Program included the stage of planning unit setting, application of mapping indices, numerical correction for repetitive analysis, creation of scenario-specific optimizations through analysis, analysis of sensitivity by scenario, review, and the selection of optimal plans among the scenarios considered. As a result of the establishment of a conservation area near Jungrangcheon Stream, which has several watershed areas, including an upper-middle-class wildlife protection zone, which was previously designated and managed as a conservation area, and the migratory protection zone downstream of Jungrangcheon Stream were designated as key conservation areas. A number of wild birds were observed in the upper reaches of Jungrangcheon Stream, adjacent to the forests of Suraksan Mountain and Dobongsan Mountain. The downstream area is a habitat for migratory birds that travel along the stream and the adjacent river ecosystem, including the Hangang River confluence and Cheonggyecheon Stream confluence. Therefore, the upper and lower reaches of Jungrangcheon Stream are connected to forest ecosystems such as Dobongsan Mountain, Suraksan Mountain, and Eungbongsan Mountain, as well as urban green area and river ecosystems in the basin area, which influence the establishment of conservation areas. This study verified the establishment and evaluation of existing conservation areas through the Marxan with Zones Program during the verification of the conservation areas and was presented as in-stream management and basin management method to manage the basin areas derived from core conservation areas determined through the program.

• Economic and Environmental Geology
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• v.55 no.5
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• pp.439-445
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• 2022

Organic pollutants that contained in stream sediments have origins of mountain soil in natural and cattle manure in human activity. Nitrogen and carbon isotope analysis for mountain soil, cattle manure and stream sediment were performed for contribution evaluation of organic pollutants in Toil stream of Yeongju dam basin. Average carbon isotope ratio(δ¹³C) is -25.17‰, -22.34‰, and -26.39‰ for river sediments, cattle manure and mountain soil, respectively. Result of carbon isotope analysis suggests that river sediments are more affected by acid soils. Average value of the nitrogen isotope ratio (δ¹⁵N) is 9.46% for river sediment, 1.99% for mountain soil, and 19.53% for cattle manure. Result of nitrogen isotopic analysis show that contribution of cattle mature is slightly higher than that of mountain soil in Toil stream sediments.

• Environmental Engineering Research
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• v.15 no.2
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• pp.111-115
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• 2010

To study the relationship between the concentrations of nitrogen in mountain streams, and anthropologic and natural factors, the water chemistry of the mountain streams in the entire Hyogo Prefecture, Japan, were investigated. A thousand mountain streams were investigated between 1998 and 2001. The concentrations of nitrate nitrogen ranged from 2.92 to 0.1 mg/L, with an arithmetic mean value of 0.45 mg/L. A number of streams showing more than 1.0 mg/L of nitrate nitrogen accounted for 8% of the mountain streams investigated. These results indicated that the concentrations of nitrate nitrogen in the mountain streams were low in the entire Hyogo Prefecture. In general, the mountain stream water in Hyogo Prefecture appears to not have been affected by wet and dry deposition originating from anthropologic sources in mountain streams and Japan. On the other hand, sites with more than 0.8 mg/L nitrate nitrogen were distributed over the entire Hyogo Prefecture, which were classified into five groups. Each group showed unique geographical, geological and anthropological characteristics. No common characteristic among five groups were discover. These results suggest that the cause of high concentrations of nitrogen in mountain streams is not from a uniform set of conditions.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.719-722
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• 2008

Forest management is done to keep ecological health of forest and to enhancement of its function. Nowadays, the abnormal climate and heavy rain happen frequently. Therefore, there are opinions that the thinning slash allowed in the mountain is flowed in rivers, which can influence in flood damage. This study, we grasp moving characteristics of thinning slash through field survey and achieved basic study about the effect of thinning slash on the discharge capacity of rivers and stream structure.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.4
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• pp.11-23
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• 2011

Mountain streams, which are major components of an entire river network, play an important role as the source of water, sediment, coarse and fine organic matter, and nutrients for lowland rivers. Therefore, dynamics and downstream linkages of each compartment of the mountain stream can be essential for watershed management in catchment scale. The dynamics and downstream linkages are understood as a development of step-pool sequences along a river course. Recently, stream restoration after flooding event often employ the development of step-pool sequences in the world. In this paper, we 1) examined the geomorphic characteristics and the role of step-pool sequences in steep mountain streams by reviewing the results of past studies, and 2) introduced the case studies of stream restoration using step-pool sequences, and finally 3) addressed design methods considering geometry and stability of artificial step-pool sequences for stream restoration. Step-pool sequences play an important role not only as roughness with energy dissipation but also as heterogeneity of stream feature for aquatic habitat. Step-pool sequences, even if they are constructed artificially along a stream, may be effective for small stream restoration considering eco-friendly torrent controls. So far the artificial step-pool sequences were employed for mountainous streams, but those would be applied to urban stream.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.333-343
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• 2012

In-stream large wood (LW) has a critical impact on the geomorphic characteristics relevant to ecosystem management and disaster prevention, yet relatively little is known about variations in its dynamics and subsequent export on the watershed-scale perspective in Korea. Here we review variations in the dynamics and subsequent export of LW as a function of stream size, which is appropriate for Korean mountain streams. In upstream channels with narrow bankfull widths and low stream discharges, a massive amount of LW, resulting from forest dynamics and hillslope processes, may persist for several decades on valley floor. These pieces, however, are eventually transported during infrequent debris flows from small tributaries, as well as peak hydrology in main-stem channels. During the transport, these pieces suffer fragmentation caused by frictions with boulders, and stream bank and bed. Although infrequent, these events can be dominant processes in the export of significant amounts of LW from upstream channel networks. In downstream channels with wide bankfull widths and high stream discharges, LW is dominantly recruited by forest dynamics and bank erosion only at locations where the channel is adjacent to mature riparian forests. With the LW pieces that are supplied from the upstream, these pieces are continuously transported downstream during rainfall events. This leads to further fragmentation of the LW pieces, which increases their transportability. With decreasing stream-bed slope, these floated LW pieces, however, can be stored and form logjams at various depositional sites, which were developed by interaction between channel forms and floodplains. These pieces may decay for decades and be subsequently transported as particulate or dissolved organic materials, resulting in the limitation of LW fluvial export from the systems. However, in Korea, such depositional sites were developed in the extremely limited streams with a large dimension and no flood history for decades, and thus it does not be expected that the reduction of LW export amount, which can be caused by the long-term storage. Our review presents a generalized view of LW processing and is relevant to ecosystem management and disaster prevention for Korean mountain streams.

• Korean Journal of Environment and Ecology
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• v.18 no.2
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• pp.197-204
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• 2004

The concept of Baekdudaegan(Korean traditional and major mountain system) was conceived toward the close of Silla Kingdom and in the beginning of the Goryeo dynasty. The concept was brought up through the Goryeo dynasty and was completed in the Joseon dynasty. We have to recognize the next two facts to restore the Baekdudaegan concept these days. Firstly, Baekdudaegan is not the highest watershed line but a domain. Secondly, Baekdudaegan is not a set of ridges but a corporate body of a water system and a mountain system. When it comes to fix the management area of Baekdudaegan, it is necessary to make criteria on the basis of traditional ideas and to include natural characteristics considering physical environment. The management area of Baekdudaegan include the third order of stream with the conservation area including the first order of stream. The most important thing in the management strategy is to prevent the damage of configuration of the ground. Baekdudaegan is a symbol of Korea spirit. Therefore, to manage Baekdudaegan wisely is one of ways to lay down the stepping stone of our country's reunification.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.454-460
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• 2012

This study was conducted for determining the influence of Sediment Control Dam dredging on benthic macroinvertebrate communities in mountain stream of Gyeongsangbuk-do. The sediment control dams were surveyed before and after dredging from mountain streams of Yecheon, Yeongju and Bonghwa in Northern part of Gyeongsangbuk-do. Sampling was taken at upper and down from 3 experimental sites and 2 control sites during May to August 2011. The identified species before dredging were 56 belonged to 31 families, 11 orders, 6 classes and 4 phyla, but after dredging it has decreased to 51 species belonged to 27 families, 10 orders, 5 classes and 4 phyla. The microhabitat damage of benthic macroinvertebrates occurred at experimental sites after dredging of sediment control dams led to reduction of the number of species and individuals. Especially, upper stream of experimental sites showed the reduction of an average of 38% species. In general, species diversity indices and species richness indices decreased after dredging; however, dominance indices increased at experimental sites. In the upper stream of experimental sites, the microhabitat damaged and became pool due to dredging. Also, velocity of flow decreased and the river bed became simply due to the sedimentary matter being finer than sand and silt. As a result, composition of functional feeding groups and functional feeding groups were relatively simpler at upper stream and the degree of community differences was greater between upper and down stream. Also, Chironomidae spp., Ephemeridae spp., and Gomphidae spp. to prefer where slow velocity of flow and lentic increased in a greater rate, and the EPT/C index to indicate the balance of the community decreased.