• Title/Summary/Keyword: forest damage

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Roadside Landslide and Ditch Erosion in Mountain Forest Road (산악지림도(山岳地林道)의 노견(路肩) 사면붕괴(斜面崩壞)와 측구침식(側溝浸蝕)에 관(關)한 연구(硏究))

  • Ma, Sang Kyu
    • Journal of Korean Society of Forest Science
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    • v.76 no.2
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    • pp.161-168
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    • 1987
  • Forest road (10 Km) constructed for the demonstrational purpose by Forest Work Training Center (F.T.C.) in 1984 was partly damaged through the roadside landside and ditch erosion by the typhoon in 1986. The causes were investigated to apply for protecting against the damage of mountain forest road. The damaging length caused by roadside landside is around 3% out of total length of 10 Km forest road, and mostly coming from the curve road filled up more than 10 m slope length on the concave mountain slope, partly from the foot of fillslope along the ever-following valley and from the both side of fillslope under the outlet of culvert with ever-flowing water. In case of ditch erosion, the big damage at V-type ditch is coming from the overflow of valley water flowing down along the inside slope. Other problem is also showing in the steepness of longitudial gradient, which is felt as a problem in road to be constructed under more than 10 persent of gradient. Other cause of ditch erosion is coming from the bury of sand basin (water collecting wall) by the debris in small diameter culvert zone, namely less than 400mm, in diameter and by the soil mass slumped down from steep wall slope. From above results the causes of F.T.C. model road damage is showing to come from no-following the general guide or little experience to protect against the forest road damage. When improved above mentioned mistakes, F.T.C. Method of mountain forest road type could be developed as a model of Mountain forest road.

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An Approach to the Spectral Signature Analysis and Supervised Classification for Forest Damages - An Assessment of Low Altitued Airborne MSS Data -

  • Kim, Choen
    • Korean Journal of Remote Sensing
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    • v.7 no.2
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    • pp.149-163
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    • 1991
  • This paper discusses the capabilities of airborne remotely sensed data to detect and classify forest damades. In this work the AMS (Aircraft Multiband Scanner) was used to obtain digital imagery at 300m altitude for forest damage inventory in the Black Forest of Germany. MSS(Multispectral Scanner) digital numbers were converted to spectral emittance and radiance values in 8 spectral bands from the visible to the thermal infrared and submitted to a maximum-likelihood classification for : (1) tree species ; and. (2) damage classes. As expected, the resulted, the results of MSS data with high spatial resolution 0.75m$\times$0.75m enabled the detection and identification of single trees with different damages and were nearly equivalent to the truth information of ground checked data.

Analysis of Burned Areas in North Korea Using Satellite-based Wildfire Damage Indices (위성기반 산불피해지수를 이용한 북한지역 산불피해지 분석)

  • Kim, Seoyeon;Youn, Youjeong;Jeong, Yemin;Kwon, Chunguen;Seo, Kyungwon;Lee, Yangwon
    • Korean Journal of Remote Sensing
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    • v.38 no.6_3
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    • pp.1861-1869
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    • 2022
  • Recent climate change can increase the frequency and damage of wildfires worldwide. It can also lead to the deterioration of the forest ecosystem and increase casualties and economic loss. Satellite-based indices for forest damage can facilitate an objective and rapid examination of burned areas and help analyze inaccessible places like North Korea. In this letter, we conducted a detection of burned areas in North Korea using the traditional Normalized Burn Ratio (NBR), the Normalized Difference Vegetation Index (NDVI) to represent vegetation vitality, and the Fire Burn Index (FBI) and Forest Withering Index (FWI) that were recently developed. Also, we suggested a strategy for the satellite-based detection of burned areas in the Korean Peninsula as a result of comparing the four indices. Future work requires the examination of small-size wildfires and the applicability of deep learning technologies.

Categorical Prediction and Improvement Plan of Snow Damage Estimation using Random Forest (랜덤포레스트를 이용한 대설피해액에 대한 범주형 예측 및 개선방안 검토)

  • Lee, Hyeong Joo;Chung, Gunhui
    • Journal of Wetlands Research
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    • v.21 no.2
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    • pp.157-162
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    • 2019
  • Recently, the occurrence of unusual heavy snow and cold are increasing due to the unusual global climate change. In particular, the temperature dropped to minus 69 degrees Celsius in the United States on January 8, 2018. In Korea, on February 17, 2014, the auditorium building in Gyeongju Mauna Resort was collapsed due to the heavy snowfall. Because of the tragic accident many studies on the reduction of snow damage is being conducted, but it is difficult to predict the exact damage due to the lack of historical damage data, and uncertainty of meteorological data due to the long distance between the damaged area and the observatory. Therefore, in this study, available data were collected from factors that are thought to be corresponding to snow damage, and the amount of snow damage was estimated categorically using a random forest. At present, the prediction accuracy was not sufficient due to lack of historical damage data and changes of the design code for green houses. However, if accurate weather data are obtained in the affected areas. the accuracy of estimates would increase enough for being used for be the degree preparedness of disaster management.

Status of Damage and Restoration Planning of Forest Trail in Choansan(Mt.) Neighborhood Park, Seoul, South Korea (초안산근린공원 숲길 훼손 실태 및 복원방안 연구)

  • Han, Bong-Ho;Ki, Kyong-Seok;Noh, Tai-Hwan
    • Korean Journal of Environment and Ecology
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    • v.26 no.6
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    • pp.923-933
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    • 2012
  • The purpose of this study targeting Choansan(Mt.) Neighborhood Park in Seoul of South Korea, whose level of visitation and use pressure has been recently increasingly high, was to understand distribution and damage status of forest trail and accordingly, set up direction of how to improve forest trail in urban area. With regards to current damage on forest trail in Choansan(Mt.) Neighborhood Park, the damaged trail with road width of over 2m and with erosion depth of over 30cm amounted to 20.3% and 36.3% respectively. And the trail section with bare land erosion, root exposure or rock exposure and the section whose impact rating class exceeded IV occupied 47.0% and 70.6%, indicating the forest trail was severely damaged. The severely injured trail route mainly included the main forest trail formed along the main ridge, the byroad connected to the main forest trail and the steep forest trail in low-lying area. Based on the study results, five types of restoration of forest trail in Choansan(Mt.) Neighborhood Park were offered, including prevention of forest trail extension, stabilization of forest trail base, maintenance of forest trail surface, vegetation restoration after closing forest trail and maintenance. Ecological restoration was additionally offered. The prevention of forest trail extension was planned to prevent expanded width of forest trail where bare land was exposed. The stabilization of forest trail base was planned to prevent erosion in the forest trail and exposure of roots. The maintenance of forest trail surface was planned in a way to protect the severely damaged forest trail surface by using wood deck and wood stairs and surfacing the road.

INSTALLATION PARAMETERS EFFECTING ON THE WIND PROOF OF A COASTAL FOREST (해안림의 방풍 효과에 영향을 미치는 설치 파라미터 분석)

  • Shin, J.H.;Chang, S.M.;Park, K.H.;Youn, H.J.
    • Journal of computational fluids engineering
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    • v.20 no.2
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    • pp.52-60
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    • 2015
  • The objective of this research lies in the effect of installation parameters influencing on the wind proof performance of the coastal forest for damage prevention. The dissipation ratio of incident wind power is developed as an assessment index to make a lumped parameter study possible. From the real field data of East, West, and South Sea bounded on the Korean peninsula, single and double storied forests were modeled in three-dimensional shape with computer aided design, and so was done the artificial structures such as wind break, sand accumulating fence, and sand dune, etc With a commercial code ANSYS-CFX, the computational result from the comparison of dissipation ratio between single and double storied forest shows the effect of composition, and also the installation effect is investigated for artificial structures with optimal dimension of distance.

Comparative Analysis of Mortality in Species of Trees after Surface Forest Fire (지표화 산불피해지의 수종별 임목 고사율 비교분석)

  • Lee, Si-Young;An, Sang-Hyun
    • Journal of the Korean Society of Hazard Mitigation
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    • v.9 no.2
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    • pp.39-43
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    • 2009
  • we studied and analyzed a tree mortality of 7 species(Pinus koraiensis etc) in surface forest fire area. In this results, the order of tree mortality was Cryptomeria japonica>Pinus koraiensis>Pinus densiflora>Pinus thunbergii>Larix leptolepis>Pinus rigida>Quercus. More damaged crown was higher tree mortality and more d.b.h was less tree mortality. Especially, oak trees in which a damage rate of crown was less 30% almost survived.

A New Optimized Localized Technique of CG Return Stroke Lightning Channel in Forest

  • Kabir, Homayun;Kanesan, Jeevan;Reza, Ahmed Wasif;Ramiah, Harikrishnan;Dimyati, Kaharudin
    • Journal of Electrical Engineering and Technology
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    • v.10 no.6
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    • pp.2356-2363
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    • 2015
  • Localization of lightning strike point (LSP) in the forest is modeled to mitigate the forest fire damage. Though forest fire ignited by lightning rarely happens, its damage on the forest is grievousness. Therefore, predicting accurate location of LSP becomes crucial in order to control the forest fire. In this paper, we proposed a new hybrid localization algorithm by combining the received signal strength (RSS) and the received signal strength ratio (RSSR) to improve the accuracy by mitigating the environmental effect of lightning strike location in the forest. The proposed hybrid algorithm employs antenna theory (AT) model of cloud-to-ground (CG) return stroke lightning channel to forecast the location of the lightning strike. The obtained results show that the proposed hybrid algorithm achieves better location accuracy compared to the existing RSS method for predicting the lightning strike location considering additive white Gaussian noise (AWGN) environment.

Atmospheric Quality, Soil Acidification and Tree Decline in Three Korean Red Pine Forests

  • Lee, Choong-Hwa;Lee, Seung-Woo;Kim, Young-Kul;Cho, Jae-Hyoung
    • The Korean Journal of Ecology
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    • v.26 no.2
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    • pp.87-89
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    • 2003
  • Although a forest damage of large area due to air pollution has not yet been found in Korea, declines of Korean red pine (Pinus densiflora Sieb. et Zucc.), the most common coniferous species, have been locally reported. To evaluate the effect of air pollution and acid deposition on the forests, SO$_2$ concentration, acid load, soil pH and tree decline were monitored for 13 years from 1988 to 2001 in Namsan, Doowang and Gyebangsan with the gradient of air pollution. During the study period, annual mean SO$_2$ concentration in Namsan, Doowang and Gyebangsan were 14 ppb, 13 ppb and 6 ppb, respectively. Annual mean acid loads in Namsan and Doowang were three to four times more than that in Gyebangsan. As respected, forest surface soils in Namsan and Doowang were acidified to pH 4.1 and 4.3, whereas that in Gyebangsan showed normal value as pH 5.4. On the other hand, decline degrees of Korean red pines in Namsan and Doowang in both 1996 and 2001 were higher than those in Gyebangsan. It is reasonable that the severer tree declines in Namsan and Doowang could be closely related with the higher air pollution, acid load, and the effects (possibly Ca deficit and Al toxicity) of soil acidification.