• Journal of Korean Society of Forest Science
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• v.108 no.1
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• pp.10-20
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• 2019

The purpose of this study is to identify the long-term area changes in the subalpine coniferous forests in Korea in order to understand the changes in the subalpine forest ecosystems vulnerable to climate change. We analyzed 20 years of time-series Landsat satellite images (mid 1990s, mid 2010s) for change detection of coniferous forests and compared with the long term changes of climate information to identify their relationship in the study area. As a result, the area of coniferous forests in the study region decreased by 25% over 20 years. The regions with largest changes are Seoraksan, Baegunsan-Hambaeksan-Jangsan, Jirisan, and Hallasan. The region with the largest decrease in area was Baegunsan (reduced area: 542 ha), and the region with large decrease in area and the largest rate of decrease was Hallasan (rate of decrease: 33.3%). As the Jeju region has the most rapid temperature rise, it is projected that Hallasan is the most vulnerable forest ecosystem affected by climate change. The result of this study shows that from a long-term perspective the overall coniferous forests in the subalpine region are declining, but the trend varies in each region. This national and long-term information on the change of coniferous forests in the subalpine region can be utilized as baseline data for the detailed survey of endangered subalpine coniferous trees in the future.

• 산림경영
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• s.187
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• pp.13-15
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• 2008

2007년 말 현재 우리나라 나무 총량은 약 6억 2,440만$m^3$로 작년 한 해 동안 9,800만$m^3$가 자란 것으로 조사되었으며, 산림면적은 6,944ha가 감소한 638만 2,000ha인 것으로 나타났다.

• Journal of Korean Society of Forest Science
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• v.90 no.5
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• pp.643-649
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• 2001

The case study of the Cooperatives' members and Sincere Forest Managers/Forest Successors was carried out to find the determinants affecting the forest investment of private forest owners and analyze their effects on it. For this the landowners' forest investment probability function was estimated using the logistical regression model. The results showed that the forest investment of the Cooperatives' members was the function of forest area, stand age, forest income, and technical assistance. Three of the variables (forest income, forest area, and technical assistance) exhibited a positive effect on the forest investment as expected, while stand age showed a negative effect unlike the expectation of the study. In case of Sincere Forest Managers and Forest Successors forest area, distance(1)(distance from forest to road accessible by vehicle), knowledge of financing program, and forest income were significant indicators for the forest investment. All these variables showed the expected signs; forest area, knowledge of financing, and forest income had a positive effect on the forest investment, and distance(1) showed a negative effect.

• Journal of Korean Society of Forest Science
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• v.88 no.3
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• pp.352-363
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• 1999

It has been rare to obtain reliable information related to the size of forest land in North Korea. Several sources of forest statistics, ranging from the first map of forest distribution in Korean Peninsula produced in 1910 to official data reported by the North Korea Government in 1997, were gathered and analyzed to define the characteristics of forest cover changes over years. In addition, Landsat satellite data obtained from 1973 to 1993 were processed for the two study areas of the provinces of Pyungyang and Heasan, where the topography and land use pattern are significantly different each other. Using three sets of multitemporal Landsat imagery, land cover ma-ps were produced by computer classification. Although forest statistics reported before 1990 are somewhat inconsistent, they mere gradually decreasing over years. The estimates of 1991 satellite data and the recent statistics reported in 1998 shows very steep decline in forest lands as compared to the ones before 1990. The abrupt decrease of forest lands after 1990 was also found on the detailed analysis of Landsat data for the two study areas of Pyungyang and Heasan. The rapid decline of forest lands may have something to do with the poor economic situation of the country and the continuing natural disasters of severe flooding and drought. Unstocked forest, which was not classified into forest land, was a very distinct and pervasive land cover type that can be easily observed on satellite imagery. Since unstocked forest land in North Korea may be a critical factor for degrading environmental quality as well as for the continuing natural disasters, further analysis is necessary to define the exact extent and the physical characteristics of the cover type.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.9-16
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• 2012

This study was conducted to scientifically analyze on the trends of cultivation area and production, and to detect the suitable site for Morus alba cultivation in forest of Buan-gun for effective cultivation. During last 3 years, the cultivation area of M. alba has steadily been increased, and the mulberry production of Jeollabuk-do has been researched as the greatest in Korea. Especially Buan-gun has the largest cultivation area of M. alba. On the other hand, as the result of detecting the suitable site for M. alba cultivation by factors of altitude, aspect, slope, soil texture, and organism content using GIS, there was the 663 ha suitable site of the total of 16,608 ha. In this area, Byeonsan-myeon, Sangseo-myeon, and Jinseo-myeon were included with the largest area, therefore, it was considered that these were the favorable regions for the expansion of M. alba cultivation area. The result of this study would be expected to be used as the effective information when establishing the expansion plan for M. alba cultivation area focused on the forest of Buan-gun in the future.

• Journal of Korean Society of Forest Science
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• v.112 no.4
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• pp.523-529
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• 2023

The aim of this study was to analyze the potential for timber harvesting in the Hongchoen Garisan Leading Forest Management Complex in the national forests, and to suggest an optimal target yield for sustainable timber harvesting. The potential for timber harvesting was assessed by analyzing the area available for timber harvesting using GIS spatial analysis, but excluding areas with a slope of more than 40° (topographical constraints), areas within 30 m on both sides of streams (environmental constraints), and areas more than 300 m away from forest roads (technical constraints). The analysis identified 3,298 ha (49%) of the total complex area of 6,679 ha as available for timber harvesting, yielding a potential harvesting volume of 608,613 m³. In the case of coniferous plantations, the potential harvesting volume was 409,721 m³, which was a very high level that accounted for 67.3% of the total. We also conducted an optimization analysis to minimize the differences in area between age classes, while maintaining sustainable timber harvesting for the next 50 years. An annual average of 41.9 ha (7,988 m³) was determined to be the optimal timber yield, and in this case, it was possible to convert the age class structure to a more stable structure after 50 years.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.4
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• pp.19-31
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• 2022

The definition of urban forest is described as all forest and trees except the Natural Parks throughout whole territory in Urban Forest Act. But the concept of urban forest in the law differs from general awareness by Korean citizen and from definitions of other countries. For discussing such differences of urban forest definition, it was tested how much urban forest area would be changed according to the various definition of urban area. The urban area was defined to be four scenarios in this study in consideration of "urban area" by National Land Planning and Utilization Act (NLPUA), 300m buffered boundary from the "urban area" proposed by World Health Organization (WHO) and forest watershed area. In the scenario 1, including forest watershed intersected with "urban area" by NLPUA, urban forest area was estimated at 1.83 million ha in which urban forest area per person was 386㎡. In the scenario 2, including forest watershed intersected with 300m buffered boundary from the "urban area" by NLPUA, urban forest area was estimated at 1.92 million ha in which urban forest area per person was 405㎡. In the scenario 3, including forest watershed intersected with "urban area" placed within administration boundary (Eup·Dong districts), urban forest area was estimated at 1.08 million ha in which urban forest area per person was 230㎡. In the scenario 4, including forest watershed intersected with 300m buffered boundary from "urban area" placed within administration boundary, urban forest area was estimated at 1.20 million ha in which urban forest area per person was 256㎡. Therefore, the boundary of urban area should be agreed clearly prior to defining the urban forest area for avoiding unclear area calculated according to different definitions.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.190-190
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• 2021

우리나라는 전체 면적의 63.0%가 산림으로 구성되어 있고, 일정면적 내 나무들의 총 부피를 의미하는 입목축적의 경우 1973년에 11.3 m³/ha에서 2015년에 146.0 m³/ha로 43년 동안 1292.0% 증가하였다. 이에 본 연구에서는 유역 면적의 70.2%가 산림에 해당하는 용담댐 상류 유역(930.2 km²)을 대상으로 SWAT(Soil and Water Assessment Tool)을 이용하여 장기간 산림 성장에 따른 수문 변화를 평가하였다. 산림 성장 변화 분석을 위해 산림청의 전국산림자원조사에서 제공하는 침엽수, 활엽수, 혼효림 식생 자료를 1980년부터 2019년까지 40년의 산림 성장 자료를 10년 단위(1980s; 1980~1989, 1990s; 1990~1999, 2000s; 2000~2009, 2010s; 2010~2019)로 구축하였으며, Terra MODIS MOD15A2 엽면적지수(LAI) 자료를 2010년부터 2019년까지 구축하였다. LAI는 연대별 식생 높이의 상관성을 고려하여 1980년부터 2019년까지 회귀하여 총 40년 자료를 구축하고 10년 단위로 활용하였다. SWAT의 검보정은 2010년부터 2019년까지 실측된 유량, 증발산량 및 토양수분을 이용하였으며 검보정 결과 유량의 평균 NSE는 0.57, R²는 0.69, RMSE는 1.66 mm/day, PBIAS는 4.95%이며, 증발산량 및 토양수분의 R²는 0.60, 0.52로 나타났다. 산림 성장에 따른 수문 변화를 관찰하기 위해 기상자료를 2010s로 고정하고 연대별 산림 정보를 입력하여 산림 성장이 물순환에 미치는 영향을 시공간적으로 평가할 예정이며, 침엽수, 활엽수, 혼효림 생장을 개별적으로 분석하여 식생별 영향을 비교 및 평가할 예정이다.

• Korean Journal of Remote Sensing
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• v.35 no.5_1
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• pp.649-663
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• 2019

The 2018 United Nations Development Programme (UNDP) report announced that deforestation in North Korea is the most extreme situation and in terms of climate change, this deforestation is a global scale issue. To respond deforestation, various study and projects are conducted based on remote sensing, but access to public data in North Korea is limited, and objectivity is difficult to be guaranteed. In this study, the forest detection based on density estimation in statistic using Landsat imagery was conducted in Gangwon province which is the only administrative district divided into South and North. The forest spatial data of South Korea was used as data for the labeling of forest and Non-forest in the Normalized Difference Vegetation Index (NDVI), and a threshold (0.6658) for forest detection was set by Gaussian Probability Density Function (PDF) estimation by category. The results show that the forest area decreased until the 2000s in both Korea, but the area increased in 2010s. It is also confirmed that the reduction of forest area on the local scale is the same as the policy direction of urbanization and industrialization at that time. The Kappa value for validation was strong agreement (0.8) and moderate agreement (0.6), respectively. The detection based on the Gaussian PDF estimation is considered a method for complementing the statistical limitations of the existing detection method using satellite imagery. This study can be used as basic data for deforestation in North Korea and Based on the detection results, it is necessary to protect and restore forest resources.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.4
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• pp.42-51
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• 2020

This study was performed to support the 6th forest basic planning by Korea Forest Service as predicting the change of forestland area by the transition of land use type in the future over 35 years in South Korea. It is very important to analyze upcoming forestland area change for future forest planning because forestland plays a basic role to predict forest resources change for afforestation, production and management in the future. Therefore, the transitional interaction between land use types in future of South Korea was predicted in this study using econometrical models based on past trend data of land use type and related variables. The econometrical model based on maximum discounted profits theory for land use type determination was used to estimate total quantitative change by forestland, agricultural land and urban area at national scale using explanatory variables such as forestry value added, agricultural income and population during over 46 years. In result, it was analyzed that forestland area would decrease continuously at approximately 29,000 ha by 2027 while urban area increases in South Korea. However, it was predicted that the forestland area would be started to increase gradually at 170,000 ha by 2050 because urban area was reduced according to population decrement from 2032 in South Korea. We could find out that the increment of forestland would be attributed to social problems such as urban hollowing and localities extinction phenomenon by steep decrement of population from 2032. The decrement and increment of forestland by unbalanced population immigration to major cities and migration to localities might cause many social and economic problems against national sustainable development, so that future strategies and policies for forestland should be established considering such future change trends of land use type for balanced development and reasonable forestland use and conservation.