• Korean Journal of Agricultural Science
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• v.37 no.2
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• pp.223-229
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• 2010

This study is to analyze location conditions for erosion control dams to be constructed in Chungcheongnam-do, Daejeon Metropolitan City, Chungcheongbuk-do and Gyeongsangbuk-do in order to establish proper conditions for erosion control dams in the future. 199 sites where erosion control dams are expected to be built in 2010 were chosen and investigated in terms of 12 factors including basin area, basin slope, and landslide risk. The results showed that erosion control dams for Chungcheongnam-do and Daejeon Metropolitan City are mostly impermeable gravity dams mainly composed of concrete. In contrast, Chungcheongbuk-do and Gyeongsangbuk-do are increasing the number of permeable or compound erosion control dams. Basin analysis at planned erosion control dam sites showed that at least 44.5% of the total area has high landslide risk. Gyeongsangbuk-do had the largest basin area for erosion control dam sites at 157.3ha, followed by Chungcheongbuk-do at 64.4ha and Chungcheongnam-do at 54.8ha. Analysis of sand deposits in the Chungcheongnam-do erosion control dam built in 2010 confirmed an average deposit of 971.8m3. The sand deposit capacity and amount of sediment control for erosion control dams have a very low correlation with basin area or flow path slope, and this needs to be addressed in future sand deposit capacity designs.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.509-512
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• 2007

The fire area need management to prevent enlargement of collapes and sinkage. and it need that repair Vegetation sack work, Soil arresting structure, Terrace-sodding works, Direct seeding works in greening works and Water cushion in erosion control dam. The whole of the Concrete stream grade stabilization structures were broken, it need to be repair. As pass the time, a lot of structures were abandoned. Therefore, it need to reorganize erosion control structures and the method of construction in the fire area

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.1
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• pp.36-43
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• 2007

This study was carried out to know how erosion control function of forests varies as forests develop in watersheds. The erosion control function among the forest welfare functions can be estimated by comparing sediment yield in stocked with non-stocked area. Sediment yield of reservoirs in stocked area were collected from farmland improvement associations. The sediment yields in non-stocked area were using USLE (Universal Soil Loss Equation) in the same reservoirs. Forests' erosion control function estimated by differences of the sediment yield between stocked and non-stocked area was static model because of no consideration on forest aging. Dynamic model was developed to consider a forest stand age. The model comprises the relationship between average forest age in watershed and sediment yield. The amount of sediment yield was different depending mother rocks. It decreased exponentially according to the forest's grow up. In case of igneous rock, the volume of sediment yield $Y_{ig}=1.4431e\;^{0.023x}$(x=average forest age), metamorphic rock $Y_{me}=4.7115e\;^{0.0694x}$, and sedimentary rock $Y_{se}=1.2808e\;^{0.028x}$.

• Journal of agriculture & life science
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• v.50 no.5
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• pp.111-120
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• 2016

The objective of this study was to provide basic information for selecting the right timing and the right place of erosion control of stream on Gyeongsangnam-do. In order to achieve this objective, a total of 526 erosion control dams and 230 mountains stream conservation facilities on the constructed places and construction planned places for the erosion control were investigated on site, forest physiognomy, and hydrologic conditions. The erosion control dams and mountain stream conservation facilities were mostly constructed in the area, which has the sedimentary rock, 200-400m of altitude, a slope of 21~30°, and II of landslide hazard map. Among the forest environmental factors, it was only similar to the construction frequency in the areas that have small diameter class, III age class. Also, we investigated the hydrological environmental factors that determine the size and numbers of erosion control dam. The places constructed to the highest frequency were below 50ha in the area, 2.1~4.0km/㎢ of drainage density, longitudinal water system, 61~90mm of maximum precipitation per hour, and 201~300mm of day maximum precipitation. As the results, the sites and floodgate conditions between the constructed places and stream conservation facilities for the erosion control showed to be very similar. Therefore, these results indicate that the erosion control of the stream of the areas, which have the disruption of mountain peaks and the high erosion risk areas, should be used on both the erosion control dam and stream conservation facilities.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.251-258
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• 2012

This study was conducted to analyze field inspection results of erosion control facilities within national forests and to suggest maintenance and management plan of erosion control facilities. The objects amounted to a total of 1,628 locations, comprising 308 erosion control dams and 1,320 erosion control areas (1,269.05 ha). The field inspections were conducted during March-June each year. The erosion control dams inspected were constructed during 1991-2005, with 96.4% of them, or 297 dams, constructed in or after 2000. The erosion control areas were constructed during 1986-2005, with 68.6% of them, or 903 areas, constructed in or after 2000. As for erosion control dams, there were 205 concrete erosion control dams and 68 concrete with boulder pitching erosion control dams, respectively, with 296 out of a total of 308 erosion control dams in a good condition. As for erosion control areas, there were many erosion control structures using stone masonry works and gabions, with 1,245 out of a total of 1,320 (94.3%) erosion control areas in a good condition. Overall, erosion control facilities within national forests were in a good condition, amply fulfilling their functions. As for erosion control facilities in a bad condition, they must be made to accomplish the goals of erosion control works through supplementation and repairs without fail. In addition, for the systematic maintenance and management of existing erosion control facilities and erosion control facilities constructed in the future as part of erosion control works, the construction of an erosion control facility management system is urgently needed.

• Journal of the Korean Society of Safety
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• v.33 no.1
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• pp.128-134
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• 2018

With the increase in frequency of typhoons and heavy rains following the climate change, the scale of damage from the calamities in the mountainous areas has been growing larger and larger, which is different from the past. For the case of Korea where 64% of land is consisted of the mountainous areas, establishment of the check dams has been drastically increased after 2000 in order to reduce the damages from the debris flow. However, due to the lack of data on scale, location and kind of check dams established for reducing the damages in debris flow, the measures to prevent damages based on experience and subjective basis have to be relied on. Under this study, the high-precision DEM data was structured by using the terrestrial LiDAR in the Jecheon area where the debris flow damage occurred in July 2009. And, from the numerical models of the debris flow, Kanako-2D that is available to reflect the erosion and deposition action was applied to install the erosion control facilities (water channel, check dam) and analyzed the effect of reducing the debris flow shown in the downstream.After installing the erosion control facilities, most of debris flow moves along the water channel to reduce the area to expand the debris flow, and after installing the check dam, the flow depth and flux of the debris flow were reduced along with the erosion. However, as a result of analyzing the diffusion area, flow depth, erosion and deposition volume of the debris flow generated from the deposition part after modifying the location of the check dams with the damages occurring on private residences and agricultural land located on the upstream area, the highest reduction effect was shown when the check dam is installed in the maximal discharge points.

• Journal of Korean Society of Forest Science
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• v.107 no.1
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• pp.59-70
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• 2018

The objective of this study was to develop erosion control dam for preventing disaster in consideration of characteristics of forested catchment near urban area, and to assess its stability and functionality to see its practicability in the field. Two types of hybrid erosion control dams were developed including debris flow prevention dam by using pillar and float board screen type and debris flow control dam by using groyne. Also, review about their static (sliding, overturning, bearing capacity) and dynamic (member force) stability was carried out. According to the result, most of the assessed items met standard safety level although there were some cases where assessed items were short of stability criteria against impact. Also, after miniature flume experiments based on the developed erosion control dam to prove structure function (material catch, deposit), it turned out the dam decreased flow sediment amount and velocity while increasing sediment-capturing capacity by 3.5 times on average compared to the one controlled without erosion control dam. When function of erosion control dam for forested catchment near urban area is quantified based on future flume experiments in a variety of conditions, the dams can be practically used in the urban area, contribution to effectively reducing debris flow damage.

• The Korean Journal of Ecology
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• v.9 no.1
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• pp.25-31
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• 1986

A study was made on the change of vegetation in Yungil area after the erosion control works. The area was divided into three major areas, the devastated land area, the afforested area and the subclimax area. Two groups of plant, i.e., the common species in all area and the different species confined in the subclimax area, were identified by the interspecific correlation analysis based on the positive correlation value at 5% significance level. High similarity among the sites in the afforested region was indicated by the DIF (difference measure) value, lower than 0.33. However, the devastated area and the subclimax area were distinguished completely. The change in species diversity has been extremely low since the erosion control works. Robinia pseudo-acacia was the dominant species in the afforested region and showed an adequate growth status.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.2
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• pp.66-74
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• 2000

This study was carried out to introduce current status and development strategy for an environmental restoration of stream side in Japan, and to consider a methodology which could be effectively applied for the environmental restoration of stream side in Korea. The strategy prospects of environmental restoration in Japan were summarized as follows: 1. We should establish a new paradigm of forest road, forest conservation and erosion control which can emphasize the restoration of the streamside ecosystem and reduce the effects of soil movement change in the areas. And we should maintain the biotic habitats to conserve native biotic community when we practice forest road, forest conservation and erosion control works. 2. In the point of view ecological conservation aspects, we should evaluate the effects of new forest conservation and erosion control methods which is emphasized on the restoration of the streamside ecosystem to apply desirable methodology to the environmental restoration of the streamside area. 3. In the past, the objective of forest conservation and erosion control was to fix a soil by construction of permanent structures. Whereas, the direction of future's forest conservation and erosion control needs to change new forest conservation and erosion control technology to prevent large scale soil movement but allow small scale soil movement to conserve sound ecosystem and biotic habitats. 4. The restoration of the streamside ecosystem should provide continuity of the streamside environment which allows desirable biological habitats, and environmentally sound facilities to harmonize the environment.

• Korean Journal of Environment and Ecology
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• v.34 no.2
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• pp.121-129
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• 2020

This study investigated the change of benthic macroinvertebrates community due to erosion control dams installed in Wonju, Gangwon by comparing the data before and after a rainy season. It selected a closed-type erosion control dam (boulder stone), an open-type erosion control dam (buttress), and a control area and surveyed two upstream points and two downstream points four times between March and September 2019. The flow velocity mostly increased in the closed-type, open-type, and control areas but decreased in St. 3 after the rainy season. The number of benthic macroinvertebrates species and their populations mostly decreased after the rainy season, and the rate of decrease in the populations in the open-type and control areas were more similar than the closed-type area. Species and populations of the EPT groups mostly decreased after the rainy season. A result of the similarity analysis showed that the closed-type and open-type areas were separated by 38.4% with the control area before the rainy season, but the open-type and control areas were separated by 51.3% with the closed-type area after the rainy season. A result of the principal components analysis (PCA) based on axis 1 showed that the closed-type area had a positive value before and after the rainy season, and the open-type and control areas had a negative value before and after the rainy season. The open-type area was more correlated with the control area than the close type. The analysis of the EPT groups showed the distribution of Ephemeroptera in the closed-type area and Trichoptera in the open-type and control areas. The result of this study shows that the installation of erosion control dam can cause changes in benthic macroinvertebrates community and that the open-type area had a smaller difference community difference from the control area after the rainy season than the closed-type area.