• Title/Summary/Keyword: forest type

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Decay Efficacies of Plywoods Manufactured by ACQ-treated Veneers of Domestic Softwood and Hardwood Species

  • Suh, Jin Suk;Lee, Hyun Mi;Hwang, Won Jung;Hwang, Sung Wook;Lee, Dong Heub;Park, Sang Bum
    • Journal of the Korea Furniture Society
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    • v.25 no.3
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    • pp.233-237
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    • 2014
  • The eco-friendly preservatives such as ACQ or CUAZ have been used in landscape architectural facilities these days. In this study, the decay efficacies of ACQ treatments were evaluated according to domestic veneer species, concentration of ACQ, weathering test, adhesive type, and fungus type. In case of veneer species, hinoki cypress and yellow poplar showed the highest and lowest decay resistance, respectively. And the decay resistance appeared to be greater in plywoods bonded by resorcinol resin-bonded plywood and non-weathering treated plywood than polyurethane resin-bonded plywood and weathering treated plywood.

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Vegetation Structure and Ecological Restoration of Disturbed Forest due to Artificial Plant (인공식재에 의해 교란된 산림의 식생구조 및 생태적 복원기법)

  • Bae, Byung-Ho;Yoon, Yong-Han;Kim, Jeong-Ho
    • Journal of Environmental Science International
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    • v.20 no.6
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    • pp.701-710
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    • 2011
  • The purpose of this study is to investigate the vegetation structure and ecological restoration of disturbed forest due to artificial plant. To this end, 12 plots were set up and surveyed. The result analyzed considering mean importance percentage(M.I.P) showed that the types were divided into three groups which are artificial planted forest type(three plots), natural forest-artificial planted forest type(four plots), natural forest type(five plots). Dominant proportion of artificial planted species were as follows: artificial planted forest type was over 60%, natural forest-artificial planted forest types were 14~49%. The range of Shannon's index of all associations was from 0.7131 to 0.7771(natural forest-artificial planted forest > natural forest > artificial planted forest). Also we suggested restoration method of vegetation for ecological value as follow: Control of density considering step and Remove of Pinus koraiensis seedlings of understory layer and shurb layer.

Evaluation of The Moment Resistance Joint Strength of Larch Glulam Using Glass Fiber Reinforced Wood Plate

  • Song, Yo-Jin;Jung, Hong-Ju;Park, Hyun-Ho;Lee, Hak-Young;Hong, Soon-Il
    • Journal of the Korean Wood Science and Technology
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    • v.42 no.5
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    • pp.571-578
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    • 2014
  • As a way of developing wooden joint development, a glass fiber reinforced wood plate was manufactured to replace a steel plate. Also, the fracture toughness was evaluated. Through application to a cantilever-type specimen made of a column and a beam, the moment resistance performance was evaluated. For the fracture toughness specimen of the wood plate, 12 types were manufactured by varying the combination of a main member (veneer and plywood) and reinforcement (glass fiber sheet and glass fiber cloth). The results of the fracture toughness test indicated that the 5% yield load of the specimen using plywood was 18% higher than that of the specimen using veneer, and that the specimen reinforced by inserting glass fiber sheets between testing materials (Type-3-PS) had the highest average 5% yield load 4841 N. Thus, a moment resistance strength test was performed by applying Type-3-PS to a column-beam joint. The results of the test indicated that compared to the specimen using a steel plate and a drift pin (Type-A), the maximum moment ratio of the specimen using a glass fiber reinforced wood plate (Type-3-PS) and a drift pin (Type-B) was 0.79; and that a rupture occurred in the wood plate due to high stiffness of the drift pin. The maximum moment ratio of the specimen using a glass fiber reinforced wood plate (Type-3-PS) and a glass fiber reinforced wooden laminated pin (Type-C) was 0.67, which showed low performance. However, unlike Type-A, a ductile fracture occurred on Type-C, and the load gradually decreased even after the maximum moment.

Modification of ginsenoside saponin composition via the CRISPR/Cas9-mediated knockout of protopanaxadiol 6-hydroxylase gene in Panax ginseng

  • Choi, Han Suk;Koo, Hyo Bin;Jeon, Sung Won;Han, Jung Yeon;Kim, Joung Sug;Jun, Kyong Mi;Choi, Yong Eui
    • Journal of Ginseng Research
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    • v.46 no.4
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    • pp.505-514
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    • 2022
  • Background: The roots of Panax ginseng contain two types of tetracyclic triterpenoid saponins, namely, protopanaxadiol (PPD)-type saponins and protopanaxatiol (PPT)-type saponins. In P. ginseng, the protopanaxadiol 6-hydroxylase (PPT synthase) enzyme catalyses protopanaxatriol (PPT) production from protopanaxadiol (PPD). In this study, we constructed homozygous mutant lines of ginseng by CRISPR/Cas9-mediated mutagenesis of the PPT synthase gene and obtained the mutant ginseng root lines having complete depletion of the PPT-type ginsenosides. Methods: Two sgRNAs (single guide RNAs) were designed for target mutations in the exon sequences of the two PPT synthase genes (both PPTa and PPTg sequences) with the CRISPR/Cas9 system. Transgenic ginseng roots were generated through Agrobacterium-mediated transformation. The mutant lines were screened by ginsenoside analysis and DNA sequencing. Result: Ginsenoside analysis revealed the complete depletion of PPT-type ginsenosides in three putative mutant lines (Cr4, Cr7, and Cr14). The reduction of PPT-type ginsenosides in mutant lines led to increased accumulation of PPD-type ginsenosides. The gene editing in the selected mutant lines was confirmed by targeted deep sequencing. Conclusion: We have established the genome editing protocol by CRISPR/Cas9 system in P. ginseng and demonstrated the mutated roots producing only PPD-type ginsenosides by depleting PPT-type ginsenosides. Because the pharmacological activity of PPD-group ginsenosides is significantly different from that of PPT-group ginsenosides, the new type of ginseng mutant producing only PPD-group ginsenosides may have new pharmacological characteristics compared to wild-type ginseng. This is the first report to generate target-induced mutations for the modification of saponin biosynthesis in Panax species using CRISPR-Cas9 system.

Future Prospects of Forest Type Change Determined from National Forest Inventory Time-series Data (시계열 국가산림자원조사 자료를 이용한 전국 산림의 임상 변화 특성 분석과 미래 전망)

  • Eun-Sook, Kim;Byung-Heon, Jung;Jae-Soo, Bae;Jong-Hwan, Lim
    • Journal of Korean Society of Forest Science
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    • v.111 no.4
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    • pp.461-472
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    • 2022
  • Natural and anthropogenic factors cause forest types to continuously change. Since the ratio of forest area by forest type is important information for identifying the characteristics of national forest resources, an accurate understanding of the prospect of forest type change is required. The study aim was to use National Forest Inventory (NFI) time-series data to understand the characteristics of forest type change and to estimate future prospects of nationwide forest type change. We used forest type change information from the fifth and seventh NFI datasets, climate, topography, forest stand, and disturbance variables related to forest type change to analyze trends and characteristics of forest type change. The results showed that the forests in Korea are changing in the direction of decreasing coniferous forests and increasing mixed and broadleaf forests. The forest sites that were changing from coniferous to mixed forests or from mixed to broadleaf forests were mainly located in wet topographic environments and climatic conditions. The forest type changes occurred more frequently in sites with high disturbance potential (high temperature, young or sparse forest stands, and non-forest areas). We used a climate change scenario (RCP 8.5) to establish a forest type change model (SVM) to predict future changes. During the 40-year period from 2015 to 2055, the SVM predicted that coniferous forests will decrease from 38.1% to 28.5%, broadleaf forests will increase from 34.2% to 38.8%, and mixed forests will increase from 27.7% to 32.7%. These results can be used as basic data for establishing future forest management strategies.

Forest Degradation and Spatial Distribution of Forest Land Development (산지개발의 공간분포와 산림훼손)

  • Yu, Jaeshim;Choi, Wontae;Lee, Sanghyuk;Choi, Jaeyong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.19 no.6
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    • pp.101-110
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    • 2016
  • Development activities in forest areas are analysed based on degree of slope, altitude, land cover, and prefectures in order to improve the capacity of existing regulations of 'feasibility of forest land conversion' and 'assessment of forest land characteristics' in this research. 959 land based developments between year 2007 and 2013 have been analysed. A development site includes over 50% of forest is categorized as a forest type, degree of slope is steeper than $8.5^{\circ}$ as mountain type, and a development included in the both categories as combined type. Distribution characteristics of the above three types are analysed by development categories and regions adopting Relative Mountain Development Index(RMDI). In results, 44.94% of total development activities have been carried out in Gyeongsang Do in order of urban development, industrial complex, sports facilities, and soil and stone collection quarrying. Developments less than $0.3km^2$ which are exempt from the feasibility of forest land conversion regulation consist 86 cases of forest type, 78 cases in mountain type, and 78 cases in combined type. SAI by slope range showed the highest value of 1.55 in less than $5^{\circ}$ and the lowest value of 0.69 between $20^{\circ}-25^{\circ}$. RMDI value in Gyeongsang Do where mountain ratio is 67.05% appeared 1.17, which is 5 times more than Gangwon Do where mountain area ratio is 81.30%, and 2 times more than Chungchung Do where mountain area ratio is 51.24%. Development activities in forestland in Korea showed unequal distributions and 26% of those developments were not subjected to the feasibility of forest land conversion regulation.

Habitat preference of wild boar (Sus scrofa) for feeding in cool-temperate forests

  • Kim, Youngjin;Cho, Soyeon;Choung, Yeonsook
    • Journal of Ecology and Environment
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    • v.43 no.3
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    • pp.297-304
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    • 2019
  • Background: The growing wild boar population has become a social issue and its feeding characteristics could affect the physical condition and the plant species composition in the South Korean forests. We aimed to reveal the preference of the wild boar on forest type and site condition as feeding grounds in two cool-temperate forested national parks, Odaesan and Seoraksan, in order to provide information to manage the growing population. Results: The 75 plots (53.6%) out of 140 plots were used as feeding grounds by the wild boar, implying a considerably large population. Especially, the observation frequency as feeding ground was the highest in Quercus forests (73.3%), and it was significantly more preferred than deciduous forest type (44.2%) and coniferous forest type (32.4%) (${\chi}^2=17.591$, p < 0.001). Significantly more and deeper pits were found in Quercus forests. Moreover, high elevation and gentle slope ridge were relatively preferred regardless of forest distribution. Conclusions: South Korean forests are growing qualitatively and quantitatively. Particularly, Quercus forest area has increased markedly, while coniferous forest area has decreased. Since the Quercus forest provides rich food sources for the wild boar, the enlargement of this forest type is expected to increase the wild boar population. The forests located at high elevations have high species diversity, and it is expected that these forests will be greatly affected by the increase in the wild boar population as preferred feeding grounds.

A Study on the Demander's Consciousness of the National Forest Management System (국유림 경영제도에 대한 수요자의 인식정도에 관한 연구)

  • Park, Kyung-Seok;Lee, Seong-Youn;Choi, Soo-Im;Kim, Hyun-Sik;Jeong, Se-Myong;An, Ki-Wan
    • Journal of Korean Society of Forest Science
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    • v.99 no.3
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    • pp.380-390
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    • 2010
  • This research was conducted to investigate the consciousness of demander on National Forest Management System and to seek for solution to activate it by measuring the variables such as the extent of goal achievement on the system, the extent of importance on function of national forest, benefit for participation of the system, and the extent of importance on the system as well as the extent of demander recognition and intention of participation on the system like, Cooperative Forest Program and People's Forest Program. The target of this investigation is to categorize consumers of National Forest Management System (NFMS) into four types such as environmental organization that do not participate in the system, environmental organization that participate in the team, company to publish a white paper on environmental and local government. As a result, the intention of participation was showed in C Type (62.7%), among fields that respondents interested in participation were tree planting and forest tending (56.2%). However, the rest of the participants were reluctant participate in the NFMS due to more benefit (72.2%) of corporate social responsibility from other fields than those from the field utilizing forestry. If only, diverse facilities related to national forest and active supporting policy are provided by Korea Forest Service, social participation using forest resources would be considered. Although 61% among A Type recognized NFMS in advance, the prime reason for not utilizing are the problems with reserving place for participates in and the inconvenience to participate in on-site. Type D shows slightly high interest in People's Forest Program (3.69). Also, it shows high interest in Forest Recreation (4.15) and Forest Reports (3.90). Particularly, it indicates that GyeongGi-Do and GangWon-Do local government prefers Forest Experience, and Cheolla, ChungCheong and GyeongSang local government prefer Forest Reports. Based on the above study, we finally suggest that legal alignment of the system, and the provision of incentive for inducement of voluntary participation by Corporate Social Responsibility (CSR), and establishment of new exclusive nongovernmental organization be able to operate the system as the solution to activate NFMS in terms of the consumer.

Vegetation Type Effects on Nutrient Status and Stoichiometry of the Forest Floor in Southern Korea

  • Choonsig Kim;Nam Jin Noh
    • Journal of Forest and Environmental Science
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    • v.40 no.1
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    • pp.9-14
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    • 2024
  • Quantitative evaluation of nutrient status and stoichiometry on the forest floor is a good indicator of litter quality in various vegetation types. This study was conducted to determine the effects of vegetation type on the nutrient concentration and stoichiometry of forest floors at a regional scale. Forest floor samples were collected from four vegetation types of evergreen coniferous forests including Cryptomeria japonica, Chamaecyparis obtusa, evergreen broadleaf, and bamboo spp. forests in southern Korea. The dry weight of the forest floor was higher in the C. japonica and C. obtusa forests than in the evergreen broadleaf and bamboo forests. The mean carbon (C) concentrations of the forest floor were highest in the broadleaf forest, followed by the bamboo forest, C. japonica and C. obtusa forests. Mean nitrogen (N) and phosphorous (P) concentrations in the the coniferous forests were lower than those in the broadleaf and bamboo forests. The mean C:N ratio was the highest in C. obtusa forest (118±25), followed by C. japonica (66±6), evergreen broadleaf (41±1), and bamboo (30±1) forests. However, C:P and N:P ratios were lower in the coniferous forests than in the broadleaf forest indicating that the stoichiometry of the forest floor varies across vegetation types. The C, N, and P stocks on the forest floor were higher in the C. obtusa forest than in the broadleaf or bamboo forests. These results highlight that vegetation type-dependent stoichiometric ratio is an useful indicator for understanding interspecific difference in quality and quantity of the forest floor.

Analysis of Consciousness on Land for the Another Use After Quarrying (채석장의 채석작업 후 부지 활용에 대한 의식 분석)

  • Park, Jae-Hyeon;Lee, Joon-Woo;Park, Chong-Min
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.13 no.3
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    • pp.143-151
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    • 2010
  • This study was carried out to use efficiently forest resources through the survey of analysis of consciousness for the application of other use following quarrying. The application types of other use following quarrying were 366 people (49.5%) for forest recreation, 164 people (22.2%) for facility application, 117 people (15.8%) for vacation facility, and 93 people (12.6%) for tree planting types. According to the test of independence between facility utility types and gender, male preferred the leisure facility type, but female preferred the forest recreation type. The tree planting type was not related to the gender, but male preferred facility application types. Also, female preferred a static use type such as recreation and walking, while male preferred a dynamic use type such as the leisure and facility application types. According to the test of independence between facility application and occupation types students and company employees preferred the leisure facility type, while school faculty and staff, self employees, and housewives preferred the forest recreation type. Public servants preferred tree planting and facility application types. The sojourn time was the overnight and 6-8 hours in the leisure facility type, within 4 hours in the forest recreation and tree planting types, and 6-8 hours in the facility application types. Other use plans of the quarry site following quarrying will be needed to establish quarry facility application models with consideration for visitor's preferences.