• Korean Journal of Ecology and Environment
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• v.47 no.4
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• pp.337-341
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• 2014

The changes in the area and standing crop of forests and the understory vegetation structure of various plantations were investigated by literature survey to predict the changes in the structure of forest ecosystems of the Korean Peninsula in the future. The greater part of forest was severely destroyed in 1950's in the Korean Peninsula. The forest standing crop has been dramatically increasing since the nationwide plantation was actively performed in 1970's and 1980's in the Republic of Korea. The area of forest was incessantly decreased at the rate of $5,500ha\;yr^{-1}$. The results of regression analysis on the changes in forest standing crop of the Republic of Korea showed that the forest might approach to the maturity stage in around 2150. It was predicted that the potential natural vegetation of Quercus mongorica, Fraxinus rhynchophyllus, Prunus sargentii, etc. would establish in the plantations of Larix leptolepsis, Pinus koraiensis and Robinia pseudoacacia in the future.

• Journal of Korean Society of Forest Science
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• v.94 no.4 s.161
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• pp.252-257
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• 2005

The study on long-term change of natural and sediment disasters such as landslides and debris flows is not thoroughgoing enough in spite of increasing of concern for disaster. Therefore, the change of natural and sediment disasters was investigated with the number of victims caused by both disasters and the ratio of sediment disasters for natural disasters was compared. The number of victims by sediment and natural disasters has apparently been decreasing despite of the change of rainfall pattern. The number of victims was changed to 140 persons/year in the late 1990s from 250 persons/year in the 1970s of natural disaster and that of sediment disaster to 20 persons/year in the late 1990s from 60 persons/year in the late 1970s. Furthermore, the ratio of sediment disaster victims to natural disaster victims has decreased from 2/7 in the 1970s to 2/15 after 1980s. But, the system of sediment disaster management and new soil erosion control works tough introduction of watershed management concept are requested because of increased landslide area in recent years (206ha in 1981 $\rightarrow$ 688ha in 1999).

• Journal of Korean Society of Forest Science
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• v.97 no.4
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• pp.458-466
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• 2008

This study was carried out to forecast long-term supply and demand of chestnut and to analyze the impacts of change in the environment of domestic and international chestnut markets. For these ends, the study developed a partial equilibrium market model, in which in-shelled chestnut market was vertically linked to shelled chestnut market. To examine the predictive ability of the model for the endogenous variables ex-post simulation was run for the period 1990 through 2003. In general, all endogenous variables reproduced the historical trends during the period except for disuse areas and newly established areas. The results of forecasting supply and demand show that domestic in-shelled chestnut production is estimated to decrease slightly from 76,447 ton in 2005 to 76,286 ton in 2020 and that exports of shelled chestnut continue to be decreased.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.334-338
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• 2011

일반적으로 유역에서 발생하는 토양손실은 붕괴사면과 표면침식, 토사류 붕괴에 의한 운반, 하상의 침식등 자연적인 요인과 도로건설, 산림의 벌채, 단지개발 등 인위적인 원인으로 발생할 수 있다. 토양손실의 발생은 농업생산성을 떨어뜨리고 목초지를 손상시키며, 물의 흐름을 방해하여 홍수위 상승, 저수지의 저수용량 감소, 고탁수 등 다양한 문제를 야기 시킨다. 이러한 문제를 해결하기 위해선 우선 토양손실 발생의 위험지역을 선정하고 그 지역을 집중적으로 관리하는 적절한 관리 대책의 마련이 필요하다. 이에 본 연구에서는 낙동강유역 전체를 대상유역으로 선정하고 토양손실 발생에 영향을 주는 여러 요소중 도시화나 농경지 확장 등 인간의 인위적인 개발로 인해 쉽게 변경될 수 있는 토지이용도를 이용하여 세부적으로 분석하였다. 토지이용도를 구성하고 있는 총 8가지의 토지이용항목 중 다른 항목들에 비해 분포면적이 매우 작은 녹지, 습지, 나지를 제외한 5가지의 항목(시가화, 논, 밭, 산림, 수역)의 분포면적을 통해 토지 이용특성에 따른 유사발생의 연관성을 파악하였으며 유역별 유사발생 위험순위를 평가하였다. 유사발생 위험순위 평가결과, 전체 낙동강유역내 유사발생 위험성이 높은 표준유역들로 구성되어있는 중권역은 내성천, 위천합류점, 합천댐유역, 안동댐유역으로 모두 높은 순위를 차지했다. 내성천유역, 위천합류점 유역, 합천댐유역은 구성하고 있는 표준유역의 절반 이상이 높은 순위들로 구성되어 있으며 안동댐유역은 구성하고 있는 소수의 표준유역이 유역내 최상위 순위를 차지하였다.

• Korean Journal of Remote Sensing
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• v.36 no.5_3
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• pp.1125-1137
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• 2020

This study aimed to propose the method of linking satellite image-based forest fire data to supplement the limitation of forest fire survey data that records only the ignition location and area of forest fire. For this purpose, a method was derived to link the fire survey data provided by the Korea Forest Service between January 2012 and December 2019 with MODIS and VIIRS image-based forest fire data. As a result, MODIS and VIIRS-based forest fire data out of 191 wildfires in the forest fire survey data were able to identify 11% and 44% of fire damage area, respectively. An average of 56% of forest damage area was extracted from VIIRS-based forest fire data compared to forest fire areas identified by high-resolution Sentinel-2A satellites. Therefore, for large-scale forest fires, VIIRS wildfire data can be used to compensate for the limitations of forest fire survey data that records only the ignition location and area.

• Journal of Korean Society of Forest Science
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• v.88 no.1
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• pp.55-62
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• 1999

Successful hosting of mesa-events such as the universiade games usually brings many external changes such as more domestic and foreign travelers, image improvement of the host country and region as well as promotion of the local economy through improving the infrastructure for the contest. This longitudinal study analyzed the effects of the winter universiade games, which were held at Muju in 1997, on the hosting rural area, based upon a multidimensional study. As a result, the inhabitants sensed that hosting the winter universiade games had large-scale investment effects on both the tourism industry and the regional development. On the other hand, hosting this kind of event was not quite successful in terms of activating the local economy, and the environment of Togyusan National Park was harmed.

• Journal of Korean Society of Forest Science
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• v.6 no.1
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• pp.24-26
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• 1967

1. The purpose of this experiment was to compose the precision of dot grid method and transects method with that of pianimeter method in area measurement. 2. The following conclusions were obtained through study on precision of area measurement of 20 plots. 3. The percentage error of each method was none significant in comparision with planimeter method. 4. The dot grid method gave 0.2% of overestimated value and the transects method 0.67% of underestimated value. 5. Accordingly, the dot grid method gave the better result than the transects method. 6. The transects method had small errors at the plots larger than 30ha. while it had big errors at plots smaller than 30ha. Therefore, it can be said that the transects method is suitable for area measurement of plots larger than 30 hectares.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.168-168
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• 2016

도시화는 수문학적으로 산림이나 농경지와 같은 투수지역을 건물, 도로 등의 불투수 지역으로 변화시키는 것이며, 이로 인하여 홍수파의 도달시간이 줄어들고 첨두유량이 증가하는 등의 수문변화를 수반하게 된다. 도로나 건물 등이 대부분을 차지하고 있는 도시지역에서는 지표면이나 식생으로부터 대기 중으로 방출되는 증발산량이 농촌이나 산림지역보다 상대적으로 적으며, 강우시 토양중의 침투량과 지표면의 저류량도 도시지역에서는 매우 적게 나타난다. 도시화 전 후의 물순환특성을 평가하기 위해서는 도시 개발 전 후의 장단기 수문 관측 결과를 기초로 물순환계를 구성하는 인자간의 관계를 정량적으로 분석하고 물순환계 구성요소의 일부 변화가 다른 부분에 미치는 영향을 평가할 필요가 있다. 즉, 도시화가 물순환 구조 변동에 미치는 영향을 정량적으로 평가함으로써 유역 전체의 건전한 물순환 체계를 유지할 수 있는 대책 수립이 가능하다. 본 연구에서는 판교신도시 개발에 따른 유역에서의 홍수 및 유출특성 변화의 정량적 규명을 목적으로 두고 집중형 모형인 HEC-HMS모형과 물리적 기반의 준분포형 모형인 CAT을 이용하여 판교신도시 개발전의 정량적 물순환 특성을 평가하였다. 대상유역은 지방 2급 하천 탄천의 지류인 운중천, 금토천이 포함된 판교유역이며, 유역면적은 약 $25km^2$이다. 이 중 유역면적의 38 %에 해당하는 지역이 개발되었으며 개발된 지역은 하류부근에 위치한다. 강우자료는 지상 강우관측소인 수원 관측소의 지점강우 자료를 이용하였다. 도시 개발 전 단계에 해당하는 2006년, 2007년 호우사상 중 누적강우량 50 mm 이상인 호우사상을 추출하여 모의를 수행하였다. 유출 특성 분석을 위해 12개의 소유역과 5개의 하도로 구성하였으며 HEC-HMS의 손실량 산정방법으로는 SCS Curve Number법을 사용하였고, 단위도는 Clark 단위 도법을 적용하였다. CAT모형에서 침투는 Rainfall Excess방법, 하도추적은 Muskingum 방법을 적용하였다. 관측치와 모의치의 적합도 검증을 위해 RMSE (Root Mean Square Error), NSE (Nash Sutcliffe Efficiency), $R^2$값을 산정하여 비교 분석하였다.

• Journal of Environmental Impact Assessment
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• v.30 no.5
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• pp.317-327
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• 2021

Industrial complexes have have been played an important role in various aspects such as national industrial development, economic growth. However, it is a cluster of manufacturing facilities which has a great impact on the surrounding area and the overall domestic environment during the operation of the facility. In this study, environmental influences and siting characteristics of industrial complexes were investigated based on the environmental impact assessment report from 2009 to 2019. The development tendency of industrial complexes is continuous decline, and major development areas are Gyeonggi, Gyeongsang and Chungcheong areas. We also confirmed that the average area of defenestration due to industrial complex is on the decline. Furthermore, the residential area and educational facilities, and the exposed population affected by industrial complex is constantly increased.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.547-558
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• 2022

In August 2020, a debris flow occurred in Gokseon, Jeollanam-do, that resulted in the death of five residents. In this study area, high-resolution 0.03 m topographic information was generated through photogrammetry, and the amount of soil movement/loss was measured. In addition, sensitivity analysis was performed for flow depth, flow velocity, and debris flow area with the program Flo-2D using the difference in simulation parameter that discharge and topographic information. Wth increasing debris flow input discharge, increases were seen in flow depth, flow velocity, and debris flow area, as ell as in the gap in results from high-resolution topographic information and low-resolution topographic information. Also, when high-resolution topographic information was used, the results were similar to the actual (measured) flow direction of the debris flow. Therefore, the application of high-resolution topographic information increases the accuracy of the debris flow analysis results compared with low-resolution information. Results could be further imporved in the future by considering geological information such as yield stress and viscosity.