• Title/Summary/Keyword: forest college

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Harvesting Cost and Productive of Tree-Length Thinning in a Pinus densiflora Stand Using the Tower Yarder (HAM300)

  • Cho, Minjae;Cho, Koohyun;Jeong, Eungjin;Lee, Jun;Choi, Byoungkoo;Han, Sangkyun;Cha, Dusong
    • Journal of Forest and Environmental Science
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    • v.32 no.2
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    • pp.189-195
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    • 2016
  • Logging equipment and method have a major influence on harvesting productivity and cost. This study investigated the productivity and operational costs of tree-length cable yarding system using HAM300, a domestically developed tower yarder. We tested HAM300 for thinning operation in Pinus densiflora stands at Gangreung, Gangwon-do on April, 2014. To assess the productivity we conducted time study for each stage of the operation. When the average time/cycle was examined for each stage of the operation, the longest was for yarding (241 sec), followed by delimbing (237 sec), felling (153 sec), and processing (103 sec). Furthermore, productivity for felling was $8.6m^3/hr$, followed by delimbing ($5.1m^3/hr$), yarding ($3.5m^3/hr$), and processing ($8.1m^3/hr$). The total cost for the tree-length logging system was $58,446won/m^3$, of which the majority was incurred by the yarding cost at $46,217won/m^3$ (79.3%), whereas the lowest cost was for felling at $2,359won/m^3$ (4.1%). We suggest that it is necessary to foster specialized operators and provide training in operating the tower yarder thereby implementing efficient harvesting system resulting from low-cost yarding.

Wildlife as Potential Vectors of African Swine Fever Virus

  • Lim, Sang Jin;Han, So Hyeon;Park, Joong Yeol;Kim, Nam Hyung;Namgung, Hun;Oh, Yeonsu;Park, Yung Chul
    • Journal of Forest and Environmental Science
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    • v.38 no.1
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    • pp.55-63
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    • 2022
  • The African swine fever virus (ASFV) remains contagious for a long time, not only in the carcass, but also in the bone marrow of an infected animal. The scavenging activity of various animals on ASFV-infected carcasses is a likely risk factor for ASFV transmission. Thus, we conducted this study to determine whether scavengers are potential vectors for ASFV. In nonprotected wild boar carcasses on the forest floor, we investigated the seasonal patterns of carcass decomposition and scavenger visits for feeding on them. The duration from fresh to early skeletonization (only bones and leather remaining) of adult carcasses was 37.6±23.1 days (n=3, range=11-51 days) in winter. The duration from fresh to later skeletonization (only bones and some fur remaining) of all carcasses, including subadult carcasses, was 8.3±2.5 days (n=4, range=7-12 days) in summer. At all three study sites, leopard cats (30.3%), large-billed crows (21.6%), and golden eagles (18.1%) were the frequently visiting species, representing more than 10% of the total visits (343 visits) in winter, whereas raccoons (21.9%), grey-backed thrushes (39.4%), and eyebrowed thrushes (14.7%) were the most frequent visitors in summer. In winter, crows or cinereous vultures were the first animals to arrive at a carcass; in summer, raccoons or crows arrived first. Our results showed that wild boars, raccoons, and leopard cats relatively frequently visited wild boar carcasses and stayed there for a long time. Wild rodents chewing on or staying near carcasses were photographed during winter. In addition to wild boars, thus, mammals, such as raccoons, leopard cats and rodents, and birds, such as accipitrids and thrushes, may be spreaders of ASFV in South Korea.

A Review of Forest Development Patten by the Length of Protection Period in Gangwondo Baekdudaegan Mountains (강원지역 백두대간 산림의 보호기간에 따른 임분 발달 양상 검토)

  • Chung, Sang Hoon;Hwang, Kwang Mo;Lim, Seon Mi;Kim, Ji Hong
    • Journal of Forest and Environmental Science
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    • v.30 no.1
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    • pp.133-144
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    • 2014
  • This study was carried out to review the pattern of forest stand development for six Gangwondo Baekdudaegan Mountains which experienced different type and duration of intensive legal protection. Vegetation data from point sampling method were employed to classify community types by cluster analysis on the basis of the importance values of canopy tree species for the study areas. The names of classified communities were given by the composition of dominant tree species. The communities were also compared one another in terms of stand structure by species diversity index. The results indicated that National Parks (Seoraksan and Odaesan) had greater proportion of mixed mesophytic forest type which was supposed to progress further forest succession process so as to have more complex and diversified stand structure. On the other hand, ordinary forest areas (Seokbyeongsan and Deokhangsan) had greater proportion of the forest types which was dominatively composed of Quercus mongolica and Pinus densiflora. The forest types with large amount of these two species would tend to develop for relatively short period of time of 40-50 years after artificial disturbances. Hyangnobong of Natural Protection Area and Hambaeksan of Natural Ecosystem Conservation Area showed intermediate stand development pattern in between National Parks and ordinary forest areas. The period of intensive legal protection of the forest area was positively correlated with species diversity index (R=0.736), and noted that the forest which received intensive protection regulation for longer period tended to show more complex and diversified stand structure.

Metabolic engineering for production of ginsenosides in Panax ginseng (인삼 사포닌 생산을 위한 대사공학)

  • Kim, Tae-Dong;Kim, Yun-Soo;Han, Jung-Yeon;Lim, Soon;Choi, Yong-Eui
    • Journal of Plant Biotechnology
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    • v.36 no.4
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    • pp.352-359
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    • 2009
  • Panax ginseng roots produce triterpene saponins called ginsenosides, which are high value secondary metabolites and has been used as drugs, detergents, sweeteners, and cosmetics. In the recent years plant cell, tissue and organ cultures have developed as important alternative sources for the saponin production in Panax ginseng. Adventitious roots and hairy roots have been successfully induced and cultured for the improvement of saponin contents. Genetic and metabolic engineering to regulate saponin biosynthesis in P. ginseng might be important way to improve the medicinal values of P. ginseng. Here we introduced the protocol of genetic transformation and recent progress of functional characterization of genes involved in saponin biosynthesis in P. ginseng.

Cellulase Production in the Digestive Organs of Reticulitermes speratus, a Native Termite from Milyang, Korea

  • Lee, Young-Min;Kim, Yoon-Hee;Cho, Moon-Jung;Shin, Keum;Kim, Yeong-Suk
    • Journal of the Korean Wood Science and Technology
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    • v.38 no.5
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    • pp.421-428
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    • 2010
  • This study investigated on enzyme production in the digestive organs of the native termite (Reticulitermes speratus) in Milyang, Korea. Four types of major cellulases [EG (endo-1,4-${\beta}$-glucanase), BGL (${\beta}$-glucosidase), CBH (cellobiohydrolase) and BXL (${\beta}$-1,4-xylosidase)] were present in the digestive organs of the termite. The strong enzyme activity for BGL was found from the native termite, and also shown that the enzyme was distributed in the salivary gland, foregut, and hindgut. BXL, which breaks down hemicellulose near the amorphous region, was detected mainly from salivary gland, foregut, and midgut. However, CBH was distributed mainly in the hindgut. Meanwhile, EG which degrades cellulose, was found mainly in the hindgut and salivary glands. These facts indicate that celluases production patterns are differ from different sites compare to the same species found in Japan, suggesting that enzyme production in the digestive organs of termites is changed according to their habitats.

Assessment of REDD+ Suitable Area for Sustainable Forest Management in Paraguay

  • Park, Jeongmook;Lee, Yongkyu;Lim, Byeongmin;Lee, Jungsoo
    • Journal of Forest and Environmental Science
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    • v.36 no.3
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    • pp.187-198
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    • 2020
  • This study extracted deforestation area and degraded forestland area, which are potential REDD+ (Reducing Emissions from Deforestation and Forest Degradation) project candidate areas in Paraguay using Land Cover Map (LCM) and Tree Cover Map (TCM). The REDD+ project objectives scenarios were set three stages: 'afforestation and economic efficiency scenario', 'local capacity reinforcement scenario', and 'Infrastructure-oriented scenario'. And then, we evaluated the project unit suitable area of the REDD+ project. All scenarios selected the evaluation factors for each scenario in addition to the area ratio factors for deforestation area and degraded forestland area and weighted values were extracted by assigning category scores. As a result of the three scenarios comparison analysis, Concepcion state score was the highest. Within Concepcion state, the Belon district had the highest score, making it appropriate as a project unit REDD+ project candidate area in Paraguay, while the San Carlos district had the lowest score. This study can be used as basic data for selecting REDD+ project candidate area in Paraguay, and it is expected to contribute sufficiently to REDD+ project if additional data or information of social, cultural and economic sectors are secured.

Physiological and Psychological Effects of Combined Forest/Thermal Therapy on Depressive Symptoms in Individuals with Alcohol and Nicotine Dependency

  • Sunhee Lee;Heeju Ro;Jungkee Choi;Youngran Chae;Soyeon Kim
    • Journal of Forest and Environmental Science
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    • v.39 no.4
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    • pp.225-234
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    • 2023
  • This study verified the effect of a combined forest/thermal therapy (FT/TT) program on participants with depressive symptoms and smoking or alcohol dependence. The participants included 20 people in the experimental group and 18 people in the control group. The experimental group participated in the FT/TT program for 2 nights and 3 days at the National Center for Forest Healing, in Hoengseong (National Hoengseong Supchewon), and a charcoal kiln operated by the Gangwon Charcoal Farming Association. The control group carried out their daily life for the same period. Psychological, physiological, and biochemical tests were conducted to determine the effect of the program. The results showed that there were significant improvements in stress, anxiety, depression, sleep quality, sleep satisfaction, and IL-6 levels. However, no significant difference was found in the cortisol, serotonin and melatonin levels between the experimental and control groups. Thus, the FT/TT therapy had psychological and biochemical effects on individuals with depression and nicotine or alcohol dependency. Further studies should be conducted to verify the effect of forest healing in various conditions.

Forest Management and Forest Resources in Bangladesh

  • Ahmed, Sheikh Ali;Chong, Song-Ho;Chun, Su-Kyoung;Kim, Jong-In
    • Journal of the Korea Furniture Society
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    • v.18 no.2
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    • pp.129-137
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    • 2007
  • Total forest land in Bangladesh is about 2.5 million hectare which is 17% of total land area. Bangladeshi forest is mainly classified into three categories- 1) Hill forest 2) Sal forest and 3) Mangroves. This forest land area is decreasing day by day. But in past decayed due to some policies, the total forest land area is increasing slowly. By this planning both government and the local people in the community are being benefited. This paper mainly discussed about the past, present and future trend of forest condition, forest land uses, sustainable forest planning and forest management.

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Effects of Forest Experience Activity on the Attitude toward Forest and Personality of Primary School Students

  • Kim, Soyeon;Choi, Jungkee
    • Journal of Forest and Environmental Science
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    • v.34 no.6
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    • pp.490-496
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    • 2018
  • The present study aimed to identify the importance of forest experience activity by examining what effects forest experience activity has on primary school students. The study population consisted of 108 students enrolled as fourth graders in primary schools in Chuncheon as of November 2017. The study measured the changes in their attitude toward forest and personality from before and after forest experience activity. The results indicated that the primary school students who participated in forest experience activity showed statistically significant increase in attitude toward forest and personality. In other words, the study identified the positive effects of forest experience activity on recognizing the importance of nature and personality building. The present study aimed to test the importance and effects of forest experience through forest experience activity outside of the classroom, as well as to present the validity of promoting forest experience activity.

Weathering of Larch Wood treated with Wood tar and Wood vinegar (목타르와 목초액로 처리한 낙엽송재의 Weathering 특성)

  • Kwon, Gu-Joong;Kwon, Sung-Min;Jang, Jae-Hyeok;Chun, Kun-Woo;Kim, Nam-Hun
    • Journal of Forest and Environmental Science
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    • v.27 no.1
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    • pp.55-60
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    • 2011
  • This study has been carried out to investigate the preservation characteristics and weathering of larch wood treated with wood tar and wood vinegar, neglected under the circumstance of outdoor exposure, buried under ground, and deposited under water. Earlywood cell wall observed by optical microscope has been collapsed due to the fungi deterioration. This phenomenon occurred more frequently in the case of woods treated with wood tar and buried under ground. Relative crystallinity of woods treated with wood tar, exposed outdoors, and untreated wood buried under ground was highest at 63% while wood tar treated wood buried under ground was lowest at 46%.