• Journal of Forest and Environmental Science
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• v.12 no.1
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• pp.13-25
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• 1996

In recent erosion control works, securing not only the disaster prevention space but the environmental space, harmonized with surrounding environment and abundant with biological resources, are emphasized. Inspired of by the fact that efforts to secure such spaces have been being briskly promoted in Japan since the beginning of 1990s', we compile and analyze the Japanese sources about the "environmentally-sound erosion control works" to contribute to the erosion control works of our country. Specifically, in this report, we deal with the subjects of "establishment of the comfortable river environment" and "environmentally-sound erosion control works" which includes "erosion control dam", "water channel works and revetments", "fish routes" and "water quality conservation works".

• Journal of Korean Society of Forest Science
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• v.20 no.1
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• pp.51-60
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• 1973

The trend and achievments of soil erosion control research in Japan were investigated through observation tours and reference work and following facts were found to be important aspects which should be considered in the soil erosion control research program in Korea. Experiments on forest and water relations, and ground water phenomena at the water source zone in Tokyo University. Studies on land-slides and erosion control dam in Kyoto University. Studies on mud-flow and snow avalanches in Hokkaido University. Studies on sanddune fixation and disaster damage prevention forests in Kyushu University. Studies on forest denudations in Nagoya University. Studies on Greening-works and soil erosion prevention chemicals in Tokyo Agriculture University. Training on planning of erosion control works and prevention of disaster damages in Forest Research Institute. Experiments on soil erosion phenomena and infiltration in Tohoku Branch, FRI. Experiments on erosion and surface stratum failure of steep slopes and their prevention methods in Railway Technical Research Institute.

• Journal of Korean Society of Forest Science
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• v.76 no.2
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• pp.145-160
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• 1987

To evaluate damage status and necessities of repair works on the forest-side erosion control structures constructed from 1966 to 1986 in Korea, developmental procedures of erosion control structures from the standard unit-cost tables established by the Forestry Administration every year, existing counter-measures for disaster erosion control system administrated by the government organization and existing status of each structure at constructed site were investigated and analyzed integrally. About 10-15% of the constructed forest erosion control structures were required to be repaired as a result of the investigation. It is actually incapable of repairing the damaged forest erosion control structures caused by excessive run-off and floodings under the existing forest-side erosion control systems. Therefore, it is necessary to put regularly repair erosion control system that will be secured by national budgetary pre-allocation system. Especially, it is also necessary to frame a new system that repair erosion control works by national budget (central government) should be possible for any scale of damages in case of the erosion control projects for the disaster counter-measures. The results of this research could be adopted as important policy data for erosion control policy-making in forest-side in Korea.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.5
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• pp.59-69
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• 2003

Most denuded mountain areas in Korea were completely stabilized by the successful work of the 1st and 2nd 10-year Forest Development Plans which targeted the reforestation of denuded forest lands. The objectives of this study are (1) to estimate the depth of organic horizon in the soil profile, (2) to investigate the change of vegetation structure, (3) to estimate the change of biomass in the erosion controlled and rehabilitated mountain areas with the passage of time. This study was carried out as the 5th times. The first study began in the year of 1985, the second study was in the year of 1988, the third study was in the year of 1992, 4th was in the year of 1998 and 5th was in the year of 2002. The first study started in the study sites which elapsed 9 years after erosion control works. The results of the study were as follows : The increase rate of soil thickness was estimated to $Y_{(cm)}=2.906log_{(yr)}-3.2476(r^2=0.917)$ during 26 years after erosion control works. The important value of pines decreased to 14.7% on upper layer. But, the important value of alders. which did not plant on erosion control work increased to 27.1%. The decrease of whole crown projection indicates that pines. and alders were heavily injured by pine leaf gall midge in the year of 1993, 1995 years and Agelastica coerulea Baly in the year of 1986, 1987 years at Yoju-gun. The young growth of pines and alders not appeared on the soil surface which elapsed 26 years after erosion control works. On the lower layer, oaks occupied over 50% in I.V, RD, RC, RF. In process of years, the increase of biomass estimated to be $Y_{(t/ha)}={0.7505X_{(yr)}}^{1.6335}\;(r^2=0.9712)$ for 26 years after erosion control works.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.1
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• pp.80-90
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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. Since the end of 20th century, the native ecology and landscape of Japan remained only a limited areas such as stream side, water side and forest areas. Therefore, recently the works of forest conservation and erosion control of environmental restoration on stream side tended to increased. The strategic prospects of environmental restoration in Japan were summarized as follows : 1. From the ecological point of view, we have to develop a certain method and technology in construction of forest conservation and erosion control to prevent environmental problem from erosion control works. 2. We have to restore not only a continuity of stream side forest from a primitive area to an estuary but also the stream side forest to preserve and restore a stream side vegetation on a primitive watershed areas. 3. We have to improve a method of construction or removal of a structure which were constructed in the stream to restore a water side environment and an interaction system for an integration on a forest land, stream, and erosion control. Additionally, we have to establish an integrated evaluation method and an enforcement system after investigation of influences on natural environment, stream, and forest etc. 4. We have to conduct an integrated research to investigate the ecosystem of stream side, and construct environmentally friendly water park and erosion control park which considered natural environment and its landscape. Additionally, we need to introduce and adopt a natural style stream construction method to restore a water side areas.

• 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.

• Journal of Korean Society of Forest Science
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• v.19 no.1
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• pp.33-48
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• 1973

The study was made to examine basic data for the eventual establishment of scientific terms in forestry and also propose tentatively correct terms in the soil erosion control measures in various fields of rehabilitation works. The 30 foundamental measures and 279 measures concerned with soil erosion control works are collected and arranged in sequence of gully, hillside, and sanddune erosion control measures and in order of Chinese, Korean and English respectively.

• 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 Forest and Environmental Science
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• v.28 no.4
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• pp.227-231
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• 2012

Reforestation is one of the most important ways to reduce erosion soil. The objective of this study was to determine the effect of jellyfish soil amendment on seedling growth for reforestation. 100g jellyfish soil amendment was applied into planting hole for the purpose of improvement of the Chamaecyparis obtusa seedling growth. Results showed that during growing period, mortality were 4.4% for the fertilized group and 8.3% for control group. The seedling average height and root diameter were 95.0 cm and 1.07 cm in fertilized group and 40.6 cm and 0.74 cm in control group. The fertilized group was found to be superior (by 1 to 5%) to control group in terms of mortality rate, seedlings height, and root diameter. The positive growth of the fertilized group can be due the increase in soil moisture and the higher availability of nutrients to the plants from jellyfish fertilizer.

• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.353-364
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• 2009

This study was conducted to evaluate the effect of erosion control works on the stream ecosystem in a mountain torrential stream. The species composition of benthic macroinvertebrates and biological water quality were investigated before and after construction of erosion control works at 5 sites. The total number of benthic macroinvertebrates before construction was 3,086 individuals including 4 phyla, 6 classes, 11 orders, 22 families, and 25 species, but after construction it has decreased to 1,208 individuals including 4 phyla, 6 classes, 10 orders, 17 families, and 19 species. Especially, the diversity, richness, and evenness indices, which were calculated based on existing number of biological species, have decreased or not produced at the erosion control sites, where biological species were not found or the minimum number of species were found. The results of community analysis of benthic macroinvertebrates and ESB(Ecological Score of Benthic macroinvertebrate community) indicated that the environmental qualities of the stream based on saprobity, environmental condition, and water quality decreased after the construction at all sites: before construction, the top of the stream was satisfactory and some satisfactory, the middle was some defectiveness, and the lower was defectiveness and very defectiveness; after construction, all parts of the stream except some parts of the top were very defectiveness. Moreover, the water quality of torrential stream was rated between I to III before construction, but after construction, it declined to $IV{\sim}V$ except control. The habitat damage of benthic macro invertebrates occurred at all investigation sites after the construction of erosion control works led to reduction of the number of biological species and water quality deterioration. The results reported in this study were collected directly after the construction of erosion control works. Therefore, additional studies are needed to further explore the effect of disaster-prevention of erosion control works and the recovery process of stream ecosystem through long term monitoring.