• Title/Summary/Keyword: forest college

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A Consideration of the Possibility of Planting Cryptomeria japonica and Chamaecyparis obtusa on the East Sea Area in Gangwon-Province by Tree Ring Dating and Climatic Factor Analysis (삼나무, 편백의 연륜과 기후인자 분석을 통한 강원 동해안 지역 식재가능성 검토)

  • Son, Ho-Jun;Kim, Young-Sol;Kim, Nam-Young;Lee, Hak-Bong;Park, Wan-Geun
    • Journal of Forest and Environmental Science
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    • v.30 no.1
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    • pp.36-44
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    • 2014
  • We measured radial growth of Cryptomeria japonica and Chamaecyparis obtusa growing in Gangneung, Boseong, Yangsan and Ulleung-do, respectively and analyzed its relationship with temperature and precipitation. We found from the result of tree ring counting that forest stands of Cryptomeria japonica in Gangneung and Boseong was 40 to 50 years old and 50 to 70 years old in Yangsan and Ulleung-do. According to climate change, the mean temperature in Gangneung was found to be $12^{\circ}C$ to $13^{\circ}C$ which was similar to that of Boseong and Yangsan 40 to 50 years ago. While the result of the radial growth measured from Cryptomeria japonica in Gangneung showed a slightly decreasing tendency compared to the other areas, Chamaecyparis obtusa showed an increasing tendency. In the case of Cryptomeria japonica, a strong negative correlation between radial growth and climate related variables including both mean temperature and mean precipitation existed in Ulleung. There was a strong negative correlation between radial growth and mean temperature for Chamaecyparis obtusa in Yangsan, although there was a positive correlation in Gangneung and Yangsan.

Rainfall Intensity Regulating Surface Erosion and Its Contribution to Sediment Yield on the Hillslope Devastated by a Shallow Landslide (산사태 붕괴사면에 있어서 표면침식에 영향을 미치는 강우강도와 그에 따른 유출토사량의 변화)

  • Kwon, Se Myoung;Seo, Jung Il;Cho, Ho Hyoung;Kim, Suk Woo;Lee, Dong Kyun;Ji, Byoung Yun;Chun, Kun-Woo
    • Journal of Forest and Environmental Science
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    • v.29 no.4
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    • pp.314-323
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    • 2013
  • To examine surface erosion and sediment export patterns on a hillslope, which was devastated by a shallow landslide and which was slowly revegetating by natural plant species, we surveyed variations in surface erosion depth on the upper-, middle- and lower-section of the hillslope, and subsequent sediment yield from the whole hillslope. The result showed that, with the passing of year, surface erosion on the devastated hillslope was regulated by higher rainfall intensity due to the supply-limitation of exportable sediment, and its variation range decreased. In addition, surface erosion on the upper-section with steep slope was regulated by higher rainfall intensity, which might result in raindrop erosion, compared to it on the lower-section with relatively gentle slope. Besides, the sediment yield from the devastated hillslope had nonlinear relationship with surface erosion depth on the hillslope because sediments on the hillslope are exported downwards while repeating their cycle of transport and redistribution. Our findings suggest the establishment of management strategy to prevent sediment-related disasters occurred during torrential rainfall events, which was based on the continuous field investigation on the hillslope devastated by landslides.

Variation in Sodium Chloride Resistance of Cenococcum geophilum and Suillus granulatus Isolates in Liquid Culture

  • Obase, Keisuke;Lee, Jong-Kyu;Lee, Sun-Keun;Lee, Sang-Yong;Chun, Kun-Woo
    • Mycobiology
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    • v.38 no.3
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    • pp.225-228
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    • 2010
  • We studied the resistance of Cenococcum geophilum and Suillus granulatus isolates to NaCl during growth under axenic culture conditions. C. geophilum isolates displayed variations in NaCl resistance; mycelial growth of most isolates was inhibited above 200mM. All isolates of S. granulatus were tolerant to high NaCl content.

Estimation of Forest Biomass based upon Satellite Data and National Forest Inventory Data (위성영상자료 및 국가 산림자원조사 자료를 이용한 산림 바이오매스 추정)

  • Yim, Jong-Su;Han, Won-Sung;Hwang, Joo-Ho;Chung, Sang-Young;Cho, Hyun-Kook;Shin, Man-Yong
    • Korean Journal of Remote Sensing
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    • v.25 no.4
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    • pp.311-320
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    • 2009
  • This study was carried out to estimate forest biomass and to produce forest biomass thematic map for Muju county by combining field data from the 5$^{th}$ National Forest Inventory (2006-2007) and satellite data. For estimating forest biomass, two methods were examined using a Landsat TM-5(taken on April 28th, 2005) and field data: multi-variant regression modeling and t-Nearest Neighbor (k-NN) technique. Estimates of forest biomass by the two methods were compared by a cross-validation technique. The results showed that the two methods provide comparatively accurate estimation with similar RMSE (63.75$\sim$67.26ton/ha) and mean bias ($\pm$1ton/ha). However, it is concluded that the k-NN method for estimating forest biomass is superior in terms of estimation efficiency to the regression model. The total forest biomass of the study site is estimated 8.4 million ton, or 149 ton/ha by the k-NN technique.

Trends in Temporal Forest Cover Change and Its Degradation in Benchi-Sheko Zone, Southwestern Ethiopia

  • Seyoum Robo;Yideg Mamo;Bedassa Regassa;Ayalew Zeleke;Tamirat Wato
    • Journal of Forest and Environmental Science
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    • v.40 no.3
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    • pp.250-258
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    • 2024
  • Forests are crucial for ecosystem stability, societal advancement, and subsistence; however, environmental changes since the 1970s, including shifting agriculture, deforestation, urbanization, increasing human population, and drought, have significantly impacted the region. The purpose of this study was to investigate the status of temporal forest cover changes in the Benchi-Sheko zone in Southwestern Ethiopia. Two types of data were collected: spatial data from satellite images of 1973, 1988, 2003, and 2017, and GPS point data. GIS software, ERDAS version 2015 software, and a handheld GPS were used for data analysis. The data of both GIS from image classification and ERDAS quantification revealed that forest cover decreased from 46,306.17 (92.67%) hectares in 1973 to 27,937.89 (55.91%) hectares in 2017; therefore 18,368.28 hectares (36.76%) decrease in forest cover was detected in the last 44 years by an average annual change of 417.46 hectares and. Based on this, it is recommended that partners working on forest conservation in the locality should enhance local people's awareness to protect forests and forest products in their day-to-day activities.

Value Chain Optimization in Timber Supply Chain: Case Study in Gangwon-do

  • Kang, Byongrho;Kim, Hyoungtae;Jang, Jaeyoung;Woo, Heesung;Woo, Jongchoon
    • Journal of Forest and Environmental Science
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    • v.34 no.4
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    • pp.304-312
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    • 2018
  • This study investigates to identify the impact factors of timber production cost on the relationship between production cost components and revenues generated by evaluating the entire timber supply chain. In this research, selected 13 logging zones as target areas and classified 14 forest production cost factors, six groups. Additionally, established 13 externalenvironmental factors with related stakeholders and forestry experts. And the BCR (Benefit Cost Ratio) method was then used to analyze the economics of each zone. Filled up a checklist and rated using 5 point scale for each target region, and extracted major cost factors for the production economy of the item. The analysis of major cost factors in the timber production revealed that wood grab equipment usage fee was the first ranked and forest trees purchase cost was ranked in the $2^{nd}$Also, the $3^{rd}$ranking was logging expenses, and transport cost, which accounted for 84% of the total cost, was ranked in the $4^{th}$. In addition, the rock land ratio, slope, timber payment (forest trees purchase cost), special timber, ratio of timber, DBH (Diameter at Breast Height), and mixed forest ratio were the factors that most affected the timber supply chain cost.

The Effects of Geological Features on Forest Devastation in Kyungpook Province Area (지질(地質)이 경북(慶北) 산림황폐(山林荒廢)에 미친 영향(影響))

  • Son, Doo-Sik;Lee, Heon-Ho;Park, Sang-Jun;Jau, Jae-Gyu
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.2 no.4
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    • pp.1-8
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    • 1999
  • Forest devastation in Korea was caused by several factors such as internal factors from geological features and external factors from artificial forest damages including fuel wood collection from forests, forest fires, shifting cultivations and so on. According to the reports of 1935, lots of forest devastation in Kyungpook province area occurred around the main and branch stream of Nakdong river. Main factors of occurring forest devastation in 1935 were investigated by the methods of forest devastation rate and the population density at the basin of Nakdong river. But based on our study, forest devastation mainly occurred in rock zones of granite and granite gneiss, next to Nakdong formation but scarcely occurred in Hayang formation. Clay of the weathered soils of granite and granite gneiss was lost by rainfall, but remaining coarse-sandy soils(or grits) have poored conditions in vegetation's growth, which are due to high level of water permeability, lack of water-holding capacity and dried conditions. Generally, pine forests are mainly growing up in these regions. It is supposed that forest devastation was accelerated due to long periods of natural regeneration and no ability of natural regeneration by sprout after frequent collections of fuel wood and cuttings from pine forest on those grit areas. These results indicated that the high rate of forest devastation occurred around the basin with the high resident population density, which was partly due to forest damages by fuel collection. Moreover, both geological features and number of residents had much influence on forest devastation. Forest devastation was positively correlated with those variables(r=+0.73).

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Role of NTFPs in Rural Livelihood of Lao PDR

  • Xayvongsa, Lamphoune;Bae, Young-Soo;Choi, Yong-Eui;Yi, Jae-Seon
    • Journal of Forest and Environmental Science
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    • v.25 no.2
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    • pp.85-91
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    • 2009
  • About 83% of the total population of Lao PDR lives in rural areas. People living near forest are highly dependent on the forest resources closed to their villages. Especially non-timber forest products (NTFPs) provide a wide range of subsistence needs and are the main source of their cash income. They also make a significant contribution to the country economy. The annual export value of NTFPs is considerably high. 708 edible NTFP species (238 edible plants and 470 animals) have been recorded so far, and about 400 plants have been reported and used as medicinal plants by Lao people. One hundred NTFP species are considered as commercial forest products. The striking trend in NTFP resources is the decline of some commercial species due to increased demand on them for commercialization, and the loss of forest by rapid population growth. To sustainablely manage the NTFPs resources, a number of new management systems are under development and support in progress by the government.

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