• Journal of Korean Society for Geospatial Information Science
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• v.19 no.1
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• pp.105-113
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• 2011

Since existing thematic maps have been made with medium- to low-resolution satellite images, they have several shortcomings including low positional accuracy and low precision of presented thematic information. Digital aerial photo image taken recently can express panchromatic and color bands as well as NIR (Near Infrared) bands which can be used in interpreting forest areas. High resolution images are also available, so it would be possible to conduct precision land cover classification. In this context, this paper implemented object-based land cover classification by using digital aerial photos with 0.12m GSD (Ground Sample Distance) resolution and IKONOS satellite images with 1m GSD resolution, both of which were taken on the same area, and also executed qualitative analysis with ortho images and existing land cover maps to check the possibility of object-based land cover classification using digital aerial photos and to present usability of digital aerial photos. Also, the accuracy of such classification was analyzed by generating TTA(Training and Test Area) masks and also analyzed their accuracy through comparison of classified areas using screen digitizing. The result showed that it was possible to make a land cover map with digital aerial photos, which allows more detailed classification compared to satellite images.

• Korean Journal of Environment and Ecology
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• v.24 no.1
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• pp.26-36
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• 2010

The purpose of this study is to investigate the change and structure of the altitudinal vegetation on the east side of Hallasan National Park, and to accomplish this research, seventeen plots($400m_2$ per zone) were set up along the Seongpanak trail starting from 750m to 1,450m(which was 700m long). These zones, according to the two-way indicator species analysis(TWINSPAN) and ordination analysis(DCA), were divided into six communities: Carpinus tschonoskii-Stryrax japonica community(I), Stryrax japonica-Quercus serrata community(II), Carpinustschonoskii-Q. serrata community(III), Q. mongolica-C tschonoskii community(IV), Acer pseudosieboldianum community(V), and Q. mongolica-Abies koreana community(VI). The findings of my investigation are as follows: the altitudinal vegetation structure of all the investigated zones from 750m to 1,000m above sea level is similar to one another, whereas the same zones from 1,000m to 1,450m above sea level showed dissimilarities among them. That indicates that altitudinal vegetation structure on the east side of Hallasan National Park has changed drastically at the 1,000m areas above sea level, and the forest age of this area is over 50 years.

• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.56-65
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• 2009

In Korea, Red pine(Pinus densiflora) stands at a very important place, historically, culturally, and emotionally and it is one of the tree species that can produce domestic timber as forest resources economically. The growing space for Red pine forest in Korea is gradually reducing while the space for deciduous tree forests including oak series is gradually increasing. Thus, it is required that the research work should be done on renewal for pine forest retention and its related forest management practices. This research aims at developing stable, sustainable management forests and inducing nature renewal by grasping growth environment and succession process through the pattern of stand and structure analysis of the red pine(Pinus densiflora) for central region. The pine forests in central region were classified into four communities, such as Acer pseudo-sibolianum, Quercus acutissima, Lindera erythrocarpa, and Pinus densiflora and they are showing different characteristics by pattern according to their growing district. There appeared a lot of red pines in the upper layer, but there existed high weight of broad-leaved forest tree species, such as oak series in the middle layer and the appearance of the red pine was meager in the lower layer. Therefore, it appears that the red pine has a high influential ecological strength in terms of correlativity; however, if the red pine in tree layer is dead by aging in nature state with the lapse of time, it is considered that oak species, such as Quercus mongolica, Quercus variabilis, and Quercus serrata will be dominant below sub-tree layer. In addition, there appear differences in characteristics and growth pattern of the red pine forest depending on stand pattern, so it is considered that a differential application method should be employed in the pine forest management.

• Clean Technology
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• v.17 no.4
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• pp.336-345
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• 2011

The total area of forest land in Korea is 64.2%, and significant forest resources can continuously be produced. However our country didn't separate the recyclable waste wood and was illegal landfill or incinerated. In this study, waste-wood and rice husk of biomass and low-grade-anthracite made refuse derived fuel by mixing and compressing. In addition, the binding effect of binders and additives were analyzed. Physical and chemical characteristics of manufactured refuse derived fuel were analyzed and evaluated suitability by compared with quality standards. A result of change with compressed and relaxed density, added 20% anthracite and 10% rice husk is optimal density change and average density increased large range when 20 wt.% P.V.A., guargum, molasses and 10 wt.% starch were added. All fuel samples be distributed over 3,500 kcal/kg LHV and grade of No. 3~4 fuels appeared. A result of the characteristics of physical and chemical compressed biomass refuse derived fuel with addictive, 12.9% of durability improvement appeared when is mixing asphalt and 5.8% of durability improvement appeared when is mixing rice bran by pretreatment of NaOH 5%.

• Korean Journal of Environment and Ecology
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• v.27 no.5
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• pp.614-624
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• 2013

The purpose of this study is to offer the raw data for establishing the plan of disaster prevention and the continuous conservation of soil ecosystem by grasping the potential soil loss and the danger of erosion using RUSLE method on whole districts in Gyeongju National Park, Korea. In the results of the average amount of soil erosion for the year, the average of all districts was 5.7 ton/ha in annual, and Namsan district was the highest in 7.6 ton/ha in annual and Seoak district was the lowest in 2.1 ton/ha in annual. The dangerous district due to the soil erosion was analyzed as under 1%, and Gumisan and Hwarange district was not serious. But Namsan district was higher than others, especially, there was intensive in all over Geumohbong. Therefore, to protect the all over Geumohbong, we will establish the valid of restoration and management. The types of land cover in Gyeongju National Park mostly showed forest, and as the average amount of soil erosion in forest was 3.7 ton/ha in annual, there was good condition. In the results of the amount of soil erosion due to landform, the deep canyon showed as 7.3 ton/ha in annual per unit area, secondly, the U-shaped valley was analyzed as 6.1 ton/ha in annual. The plain and high ridge were predicted that there occurred the small amount of soil erosion. In future, if we will analyze the amount of soil erosion in Korean National Parks, we will offer the help to establishing the plan of conservation and restoration on soil ecosystem in whole National Parks.

• Journal of Environmental Policy
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• v.13 no.3
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• pp.3-19
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• 2014

Large-scale unband development resulted from the rapid economic growth in the Republic of Korea has brought about the habitat destruction for the native animals and plants living in forest and farmland. In order to resolve this problem, it is necessary to consider the natural ecosystem as an organism and to preserve the natural ecosystem by managing ecologically significant habitat consistently. Especially, the local governments should be able to establish regional ecologic networks in consideration of the ecological connectivity and the environmental and ecological excellence, and to reflect them into the local development plans. In regard to this, the methods of the regional ecological network establishment was presented, making use of the results including the national ecological network which assessed the ecological connectivity of the nation and the environmental and ecological assessment results of the Environmental Conservation Value Assessment Map which was designed to analyze and assess the national environmental and ecological values quantitatively. Making use of the case of Gyeongsangnam-do; the results presented that the existing national ecological network in the core region has expanded from $2,986km^2$ to $4,049km^2$ and the existing national ecological network in the buffer region has expanded from $2,940km^2$ to $3,006km^2$. Referring to the regional ecological network in the process of the local development plans could contribute to the increase in biodiversity and the integrated local environmental management including the ecosystem preservation.

• Spatial Information Research
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• v.17 no.3
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• pp.261-268
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• 2009

This study accomplished to draw a soil erosion map and a grade map of soil loss hazard in Korea. RUSLE and Rainfall-runoff (R) factor, which was estimated by using the rainfall data observed in 59 meteorological stations from 1977 to 2006 (for 30 years). FARD was used to analyze the frequency, and the whole country R factor was estimated according to the frequency. In the analysis of estimating the whole country R factor, Nakdong river has the smallest vaule, but Han river has the biggest value. According to the result of analyzing soil loss, soil loss occurred in a grass land, a bare land and a field in size order, and also approximately 17.2 ton/ha soil loss happened on the whole area. The average soil loss amount by the unit area takes place in a bare land and a grass land a lot. The total amount of soil loss in 5-year-frequency rainfall yields 15,000 ton and, what is more, a lot of soil loss happens in a paddy field, a forest and a crop field. The grade map of soil loss hazard is drawn up by classifying soil loss hazard grade by 5. As a result of analyzing soil loss, the moderate area which is the soil loss hazard grade 2 takes up the largest part, 72.8% of the total soil loss hazard area, on the contrary, the severe soil loss hazard area takes up only $1,038km^2$ (1.1%) of the whole area. The severe soil loss hazard area by land cover shows $93.5km^2$ in a bare land, $168.1km^2$ in a grass land and $327.4km^2$ in a crop field respectively.

• Korean Journal of Environment and Ecology
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• v.15 no.3
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• pp.276-285
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• 2001

This report surveyed degradation of forest environment and rehabilitation in Ashio of Japan. Since 1880, a large scale forestry in this area has been destroyed by sooty smoke, and the local government invested heavily to rehabilitate the damaged forestry and denuded mountains. These degradations are due to complex operations, such as sulfurous acid gas from copper refinery, forest fires, steep slope and disadvantageous climate. The rehabilitation works on degraded forestry(2,399ha) were undertaken by tree planting fur three years from 1897. However, forest degradation and disasters were continued, and the total damaged areas were about 2,400~3,000ha in 1956. A Manual labor method, a Helicopter method and also Combination of manual labor and helicopter method had been adopted to rehabilitation works from 1945 to 1996, while 828.19ha of the degraded mountains was rehabilitated. Total investment for those projects was 80 billion yen. A debris control dam, a soil arresting structure, a vegetation-block, a vegetation sack measures and tree planting have implemented significantly fur the method of rehabilitation. An objective of manual labor works is a complete rehabilitation on each place through 3 stage working. The revived green areas accounted fur 49% of the total, and the entire afforest areas are less than 10%. In coming 25 years, an amount of 21.3 billion yen will be invested to rehabilitate 564ha of degraded mountain lands. However, it is impossible to estimate that how long it will take until the whole degraded mountain lands are completely rehabilitated. Rehabilitation works in Ashio may be applicable to environmental restoration and revegetation in the abandoned coal-mine lands of Korea.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1134-1138
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• 2010

호소의 수질오염 문제를 해결하기 위해선 우선 소하천에서 강우유출에 의한 비점오염물질이 어디서 얼마나 발생하는지에 대한 정량적인 조사가 필요하다. 그러나 유역의 오염원에 대한 정량적인 조사가 이루어지려면 많은 비용과 시간 그리고 노력이 필요하다. 따라서 본 연구에서는 대청호 상류유역의 소하천인 안내천을 대상으로 강우유출수 조사를 실시하고, 높은 예측 정확성 때문에 세계적으로 널리 쓰이고 있는 Long-Term Hydrologic Impact Assessment(L-THIA)을 이용하여 실측데이터와 L-THIA 모델의 결과를 비교하였다. 안내천의 유역면적은 16.5 $km^2$로 유역의 약 69.5%가 산림, 농업 및 초지지역이 25.3% 그리고 주거지역이 2.6%로 조사되었다. 수질분석을 위하여 자동수질시료채취기(ISCO sampler 6712)를 설치하여 시간단위의 시료를 채취한 뒤 수질농도를 측정하였다. 수질항목은 유기물질인 $BOD_5$, TOC, T-N, T-P 항목에 대하여 수질오염 공정시험법으로 분석하였다. WHAT 시스템을 이용하여 분리된 직접유출량은 315.5~161,835.1 $m^3$의 범위로 나타났다. 직접유출량을 이용하여 산정한 유역의 EMC 농도는 안내천 유역의 $EMC_{BOD}$는 1.0~2.4 mg/L, $EMC_{TOC}$는 1.429~5.491 mg/L, $EMC_{COD}$는 2.2~10.2 mg/L, $EMC_{TN}$은 2.906~10.864 mg/L, $EMC_{TP}$는 0.029~0.285 mg/L의 범위를 보였다. 또한 실측된 유량과 농도를 이용하여 산정한 오염부하는 안내천 유역이 $BOD_5$ 37.9~390.9 g, $COD_{Mn}$ 0.8~1,657.5 g, TOC 0.54~791.83 g, T-N 0.968~1,758.174 g, T-P 0.011~42.139 g의 범위로 나타났다. L-THIA 모델을 이용하여 직접유출량의 산정된 결과와 실측 결과를 비교 분석한 결과 결정계수와 유효지수가 0.95와 0.93으로 높게 나타나 대청호 상류유역에서 발생하는 유출량을 모의하는데 적절할 것으로 판단된다. 토지이용도와 토양도 그리고 일 강우자료만으로 구축되는 L-THIA 모델을 이용하여 대청호 상류의 소하천 유역에 대하여 비점오염원 유출특성을 해석하는 것이 가능 할 것으로 판단된다.

• Journal of Korea Water Resources Association
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• v.38 no.8 s.157
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• pp.645-653
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• 2005

Water cycle analysis in the Cheonggyecheon watershed(river length: 13.75 km, area: $50.96\;km^2$) was performed using WEP model, a physically based distributed rainfall-runoff model. As the application results of the model, the hydrological characteristics of the Cheonggyecheon watershed are significantly consistent with those of a typical urbanized watershed. The direct runoff from the watershed was larger and the evapotranspiration. was lower, and the response of runoff to rainfall was occurred very fast, as compared to forest watersheds. The river channel routing simulation results are similar to the change pattern and scale of the field data. The possible supply period of instream flow from Cheonggyecheoon watershed itself was estimated using WEP. According to the WEP simulation results for the annual water balance of the Cheonggyecheon watershed in 2002, the amount of direct runoff, infiltration and evapotranspiration were 830 mm, 388 mm and 397 mm respectively for an annual precipitation of 1,388 mm. The runoff to rivers was 1,288 mm. And the proportion of direct runoff, intermediate runoff and groundwater runoff were $67.6\%,\;12.7\%$ and $19.7\%$ respectively.