• Journal of Forest and Environmental Science
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• 제34권6호
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• pp.451-456
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• 2018

The use of single component distribution to describe the irregular stand structure of degraded forest often lead to bias. Such biasness can be overcome by the application of finite mixture distribution. Therefore, in this study, finite mixture distribution was used to characterise the irregular stand structure of the Gmelina arborea plantation in Omo forest reserve. Thirty plots, ten each from the three stands established in 1984, 1990 and 2005 were used. The data were pooled per stand and fitted. Four finite mixture distributions including normal mixture, lognormal mixture, gamma mixture and Weibull mixture were considered. The method of maximum likelihood was used to fit the finite mixture distributions to the data. Model assessment was based on negative loglikelihood value ($-{\Lambda}{\Lambda}$), Akaike information criterion (AIC), Bayesian information criterion (BIC) and root mean square error (RMSE). The results showed that the mixture distributions provide accurate and precise characterisation of the irregular diameter distribution of the degraded Gmelina arborea stands. The $-{\Lambda}{\Lambda}$, AIC, BIC and RMSE values ranged from -715.233 to -348.375, 703.926 to 1433.588, 718.598 to 1451.334 and 3.003 to 7.492, respectively. Their performances were relatively the same. This approach can be used to describe other irregular forest stand structures, especially the multi-species forest.

• Journal of Forest and Environmental Science
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• 제31권3호
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• pp.192-201
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• 2015

Information on plant diversity and community structure are required to chalk out necessary actions for conservation management. The present study assessed the composition and diversity of tree species in Kamalachari Natural Forest of Chittagong South Forest Division, Bangladesh, during April 2010 to November 2011. A total of 107 tree species belonging to 72 genera and 37 families were recorded, where Moraceae family was represented by maximum (11) species. Density, Basal area and volume of tree species were $418{\pm}20.09stem/ha$, $21.10{\pm}2.62m^2/ha$ and $417.4{\pm}79.8m^3/ha$ respectively. Diameter and height class distribution of tree species revealed an almost reverse J-shaped curve. Both the number of species and percentage of tree individuals were maximum in the lower DBH and height ranges. Anthropogenic disturbances like illegal tree cutting, over extraction, settlement inside forest area etc. were noticed during the study, which are supposed to cause gradual decrease of both tree species and individuals in the higher DBH and height classes. However, Artocarpus chama was found dominant showing maximum IVI followed by Schima wallichii, Aporosa wallichii, and Lithocarpus acuminata. The quantitative structure of the tree species of Kamalachari natural forest is comparable to other tree species rich tropical natural forests. The findings of the study may help in monitoring future plant population changes of the identified species and adopting species specific conservation programs in Kamalachari natural forest.

• Journal of Forest and Environmental Science
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• 제28권4호
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• pp.254-262
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• 2012

The purposes of the research in related to FSC in JuJe experimental forests (JJEFs) is to make pre and post socio-economic comparisons and play an important role of FSC, and recognition change to FSC timbers and to make an analysis to consumers' needs. As the results of onsite survey in 2005, respondents show a high awareness of SFM and FSC in comparisons of 2004, and the JJEFs play a critical role to make SFM and FSC advertisement worldwide, such as consumers' satisfaction to SFM and FSC is high. Hence provision of JJEF information such as job creation and socio-economic impacts to stockholders could make their satisfaction improving. Most of respondents to the FSC of JJEF represent a positive rate while low awareness to FSC timber is represented. Therefore, necessary information about JJEF FSC with forest management, process and consumption pattern of FSC is required into citizens. The final results prove that FSC effects such as 1.3 billion won direct additional benefits in terms of socio-economic aspects including environmental benefits and job creation and economic effects are enough to offset 1.3 billion won additional costs.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.533-536
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• 2007

The LiDAR data structure has the potential for modeling in three dimensions because the LiDAR data can represent voxels with z value under certain defined conditions. Therefore, it is possible to classify the physical damaged degree of vegetation by forest fire as using the LiDAR data because the physical loss of canopy height and width by forest fire can be relative to an amount of points reached to the ground through the canopy of damaged forest. On the other hand, biological damage of vegetation by forest fire can be explained using the NDVI (Normalized Difference Vegetation Index) which show vegetation vitality. In this study, we graded the damaged degree of vegetation by forest fire in Yangyang-Gun of South Korea using the LiDAR data for physical grading and digital aerial photograph including Red, Green, Blue and Near Infra-Red bands for biological grading. The LiDAR data was classified into 2 classes, of which one was Serious Physical Damaged (SPD) and the other was Light Physical Damaged (LPD) area. The NDVI was also classified into 2 classes which are Serious Biological Damaged (SBD) and Light Biological Damaged (LBD) area respectively. With each 2 classes ofthe LiDAR data and NDVI, the damaged area by forest fire was graded into 4 degrees like damaged class 1,2,3 and 4 grade. As a result of this study, 1 graded area was the broadest and next was the 3 grade. With this result, we could know that the burned area by forest fire in Yangyang-Gun was damaged rather biologically because the NDVI in 1 and 3 grade appeared low value whereas the LiDAR data in 1 and 3 grade included light physical damage like the LPD.

• 대한원격탐사학회지
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• 제39권6_1호
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• pp.1341-1352
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• 2023

위성영상 기반의 정규식생지수(normalized difference vegetation index, NDVI)는 넓은 영역에서 주기적인 정보를 수집할 수 있어 산림 및 농업 모니터링에 주로 사용된다. 그러나 광학센서 기반 식생지수는 구름 등의 영향으로 일부 지역에서 결측을 가지기 때문에, 본 연구는 전천후 및 주야에 관계없이 관측 가능한 Sentinel-1의 합성 개구 레이더(synthetic aperture radar, SAR) 영상을 활용하여 Sentinel-2 NDVI 결측값을 복원하는 모델을 개발하였다. 이는 광학적으로 관측이 어려운 구름 조건이나 야간에도 NDVI를 추정할 수 있는 잠재력을 보여준다. Automated machine learning (AutoML)을 활용한 비선형 결측복원모델의 5폴드(fold) 교차검증 결과, 절대오차 7.214E-05, 상관계수 0.878의 NDVI 복원 성능을 보였다. 이를 통해 시공간 연속적인 NDVI 생산 방법론을 발전시켜, 전천후 식생 모니터링에 필요한 정보 생산에 기여할 수 있을 것으로 기대된다.

• 한국지리정보학회지
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• 제7권2호
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• pp.57-68
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• 2004

우리나라 산림행정 업무의 대부분은 서류 및 대장에 의존하고 있는 실정으로 신속, 정확하고 다양한 업무 처리를 위해서는 첨단의 공간정보기술을 이용한 과학적인 산림정보 관리시스템의 개발이 시급하다. 특히 지리정보시스템(GIS)과 항공사진 활용기술의 도입은 산림이용기본계획이나 산지개발, 산림자원 관리 및 산림보호 정책 등의 의사결정지원에 효율적으로 기여할 수 있을 것이다. 본 연구에서는 GIS와 항공사진(1998년도 촬영)을 기반으로 주요 산림정보인 수치지도, 수치임상도, 임야도 및 관련 속성데이터 등을 가공하여 DBMS(data base management system) 내에 저장하였으며, 이를 기반으로 세부 응용시스템인 지번별 임야정보 검색, 산지이용개발 정보관리, 법정제한림 정보관리, 산림자원 정보검색 등의 인터페이스를 개발함으로써 산림 관련 실무자가 산림정보의 종합적인 공간분석 및 질의 검색이 가능한 산림정보 관리시스템을 구축하였다. 본 시스템의 구축으로 산림의 효율적 관리는 물론 경제적인 산림자원 및 임산업 육성과 쾌적한 산림환경을 조성할 수 있을 뿐만 아니라 관련 부서들 간의 표준화된 공간 자료 공유와 과학적인 정보체계의 연동으로 산림자원 관리를 위한 집약된 공간 및 전자 정보화 인프라 구축의 기반을 마련할 것으로 사료된다.

• The Korean Journal of Ecology
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• 제19권4호
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• pp.305-320
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• 1996

It is necessary to obtain information about the productivity of the human-influenced forest and to understand the consumption of biomass resources in secondary forest in order to examine the resource flux by human activity in rural landscape. Thus the aims of this study were to elucidate the biomass and their use of secondary Pinus densiflora forests and to discuss sustainable utilization of secondary forests in rural landscape system. This study was carried out in Yanghwa-ri, Kongjugun, Chungcheongnam-do, central Korea. The changes of growth rate and aboveground biomass of a pine forest for 2 years were analyzed to understand forest management regimes in rural pine forests. Through allometric equations deduced from 25 sample trees, biomass was estimated. The biomass increase of pine forest was approximately 16.36 t/ha/yr in the unexploited stand and 12.24 t/ha/yr in the exploited stand. These were nearly equal to those of natural pine forests in central Korea. This result proved that human-influenced pine forest in rural landscape as well as the natural one has high potentiality to provide forest products. Making graveyard in forest-land was the important disturbance and land-use which currently occurring in rural landscape in the study area. Finally, we presented some forest management for stutainable and positive uses of secondary forests as one of the local energy resources in terms of the holistic landscape-ecological view.

• 한국농림기상학회지
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• 제17권2호
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• pp.126-135
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• 2015

본 연구는 전라북도 남원시의 맞춤형 조림지도인 적지적수도를 제작하기 위해 수행하였다. 이를 위해 남원시에 분포하는 주요 수종별 지위지수 추정식을 개발하고, 수종별로 적지에 적합한 입지조건을 반영한 생육범위를 고려하여 각 수종의 적지분포를 공간적으로 평가하였다. 남원시에 분포하는 주요 8개 수종별 지위지수 추정식은 각각 4-5개의 환경인자 조합이 관여하는 것으로 분석되었으며, 전체 27개의 환경인자 중에서 15개가 수종별 지위지수 추정에 사용되었다. 특히 사면위치($X_7$)와 경사형태($X_8$), B층 건습도($X_{11}$), 연최저 기온($X_{15}$), 온량지수($X_{16}$) 비생장기간 5개월 동안의 총강수량($X_{23}$), 월평균 상대습도($X_{24}$), 그리고 생장기간 초기 3개월 동안의 월평균 상대습도($X_{25}$)가 수종별 지위지수 추정식에 많이 포함되는 것으로 판명되었다. 이상과 같은 방법으로 남원시의 적지적수도를 제작한 후, 적합성 검증을 위해 현지 확인 조사를 수행하였다. 현지 확인 결과 본 연구에서 제작한 적지적수도는 사용 가능한 자료의 한계에도 불구하고 수종별 적지분포를 비교적 무난하게 표현하고 있는 것으로 평가되었다. 하지만 부적지로 평가된 일부 지역의 경우 수정 및 보완이 필요한 것으로 나타났다.

• 농촌계획
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• 제11권4호
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• pp.47-57
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• 2005

The goal of this research is to evaluate landscape-ecological characteristics of watersheds in the Nakdong River Basin by using Geogaphic Information System (GIS) and landscape indices for integation of spatio-temporal informations and multivariate statistical techniques for quantitative analysis of forest landscape. Fragmentation index and change matrix techniques using factor analysis and grid overlay method were used to efficiently analyze and manage huge amount of information for ecological-environmental assessment (land-cover and forest landscape patterns). According to the results based on the pattern analysis of land-cover changes using the change detection matrix between 1980s and 1990s, addition on 750km$^2$ became urbanized areas. The altered 442.04km$^2$ was agricultural areas which is relatively easy for shifting of land-use, and 205.1km$^2$ of forests became urbanized areas, and average elevation and slope of the whole altered areas were 75m and 4$^{\circ}$. On the other hand, 120km$^2$ of urban areas were changed into other areas (i.e., agricultural areas and green space), and fortunately, certain amount of naturalness had been recovered. But still those agricultural areas and fallow areas, which were previously urban areas, had high potential of re-development for urbanization due to their local conditions. According to the structural analysis of forest landscape using the landscape indices, the forest fragmentation of watersheds along the main stream of the Nakdong River was more severe than my other watersheds. Furthermore, the Nakdong-sangju and Nakdong-miryang watersheds had unstable forest structures as well as least amount of forest quantity. Thus, these areas need significant amount of forest through a new forest management policy considering local environmental conditions.

• 한국환경교육학회지:환경교육
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• 제21권1호
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• pp.31-44
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• 2008

This study was aimed at developing and providing textbook writers with information and materials required to introduce forest education ideas and paradigm into primary, middle, and high school students, responding to establishment of the new national curriculum. Research methods included interview with school teachers, literature review on forest education and policy, analysis of writings and drawings of elementary school students. As a primary result, the study produced a framework that can be applied to analyze and understand how people think of and put a value on forest, consisting of 1) Resource-Economic Perspective, 2) Environmental-Ecological Perspective, 3) Cultural-Educational Perspective, and 4) Existential-Ethical Perspective. To test its validity, the developed framework was applied to the processes of reorganizing and interpreting the outcomes of teacher interview and writings and drawings of elementary school students. The results of applications showed that current school education mostly focused on ecological-environmental (about 50%) and cultural-educational (about 30%) perspectives on forest. To improve the quality of current forest education in schools, five main directions including integration, balance, interrelatedness, identity, and systematic approaches were suggested.