• Title/Summary/Keyword: silviculture

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Construction Of Fire Resistant Forest Belts (산불피해를 줄일 수 있는 조림방안 - 내화수림대 조성 -)

  • Lim, Joo-Hoon
    • Journal of the Korean Professional Engineers Association
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    • v.38 no.3
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    • pp.1-5
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    • 2005
  • As a method of anti-fire construction in forest region it is proposed to build fuelbreak(vegetated firebreak). Fuelbreak can separate the large area conifer forest into smell parts combined with natural firebreaks. Fuelbreaks can prevent forest fire effectively and also have other functions benefiting the forest ecosystem and environment. 3 kinds of construction skills are introduced for the silviculture technique to build fuelbreaks. And it is proposed to build the firebreaks network in national scale.

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A Case Study of Risk Assessment of Ozone Impact on Forest Tree Species in Japan

  • Watanabe, Makoto;Yamaguchi, Masahiro;Matsumura, Hideyuki;Kohno, Yoshihisa;Koike, Takayoshi;Izuta, Takeshi
    • Asian Journal of Atmospheric Environment
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    • v.5 no.4
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    • pp.205-215
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    • 2011
  • Ozone ($O_3$) is a main component of photochemical oxidants and a phytotoxic air pollutant. Although the current levels of tropospheric $O_3$ in East Asia could adversely affect productivity of forest tree species, risk assessments of $O_3$ impact were limited. In this paper, we summarize the methodology of risk assessment of $O_3$ on forest tree species based on our two previous studies, risk assessments of $O_3$ impact on the growth of Fagus crenata by Watanabe et al. (2012) and on the annual carbon absorption of three representative conifers, Cryptomeria japonica, Pinus densiflora and Larix kaempferi by Watanabe et al. (2010). $O_3$ sensitivity of each tree species obtained from an experimental study, $O_3$ exposure and atmospheric N deposition based on field monitoring and vegetation survey were integrated by geographic information system method. Based on the results, we conclude that the area with high risk of $O_3$ impact does not necessarily correspond to the area with high $O_3$ exposure. The varieties of tree habitat, tree sensitivity to $O_3$ and annual carbon absorption among the tree species, and N deposition-induced change in the $O_3$ sensitivity of F. crenata are raised as the factors of discordance between areas with high risk and those with high $O_3$ exposure. In the last part of this paper, we discuss the present uncertainty and perspectives of risk assessment for the future studies on the impact of $O_3$ on forest tree species in East Asia.

A GIS-based Supply and Demand Potential Mapping of Forestry-biomass Energy (GIS를 기반으로 한 산림바이오에너지의 공급 및 수요 잠재지도 작성)

  • Lee, Jung-soo;Lee, Hu-cheol;Seo, Hwan-seok
    • Journal of Korean Society of Forest Science
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    • v.98 no.3
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    • pp.311-318
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    • 2009
  • This study purposed to construct supply and demand potential map of forest bioenergy with a GIS-based decision support system. The target areas of this study were a part of the forests in Yongdong region, Gangwondo, and most types of forests were pinus densiflora, pinus koreaiansis, and Oak. Data about forest type, age classes, the number of households, regional silviculture planning was stored in GIS to define the potential areas for supplying potential bioenergy from the forests, and to assess biomass available for a household. Theoretical potential biomass energy based on silviculture plan was estimated in average 3,144 Tcal, and this quantity will be enough to supply the quantity of demand of households in that area. However, if it assumed that average collecting rates of Kangwon province were 10%, the available quantity of biomass will be between 6% and 15% of demand. If the collecting rates were 60%, the supply of biomass could exceed the quantity of demand in certain cities.

Clonal Propagation in Commiphora Wightii (Arnott.) Bhandari

  • Mishra, Dhruv Kumar;Kumar, Devendra
    • Journal of Forest and Environmental Science
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    • v.30 no.2
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    • pp.218-225
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    • 2014
  • Studies were carried out to standardize and develop a suitable macro-propagation technology for large scale production of superior clonal stock through stem cuttings in Commiphora wightii Arnott (Bhandari), a data deficient medicinal plant of arid region. For the purpose, three experiments were conducted. The first experiment was tried to elucidate the impact of various cutting diameters (0.50-0.75 cm, 0.75-1.00 cm, 1.00-1.50 cm, and >1.50 cm) in combination with varying growing conditions (sunlight, shade house and mist chamber) on shoot sprouting and rooting without using exogenous plant growth regulators. Cutting diameter (size 0.75-1.00 cm) in mist chamber has shown maximum sprouting (90.00%) and rooting (73.33%), primary root (6.67) and secondary root (16.67) followed by 1.00-1.51 cm in mist chamber. Minimum sprouting (40.00%), rooting (33.33%), number of shoot (1.33), primary root (1.00) and number of secondary root (1.00) was recorded in cutting diameter (size >1.50 cm) in sunlight. Second experiment was performed to find out optimum growth regulator concentration of rooting hormone (100, 200, 500 and 1000 ppm) of Indole-3-acetic acid (IAA) and Indole-3-butyric Acid (IBA) on adventitious root formation on cuttings diameter (size 0.25-0.50 cm) in comparison to control. Maximum rooting percentage (93.33%) was recorded in 200 ppm followed by 500 ppm (86.66%) of IBA as compared to control, which showed only 60 per cent sprouting. Third experiment was performed with newly formed juvenile micro-cuttings treated with varying concentrations of IAA and IBA. The juvenile cuttings (size 6-10 cm, basal dia <0.25 cm) were selected as micro-cuttings. The cuttings treated with IBA (500 ppm) showed 64.30% rooting as compared to other treatments. Results of above experiments indicate that cuttings (size 0.75-1.00 cm dia) may be developed in mist chamber for better performance. While using heavier cuttings, no growth promoting hormones is required however; growth regulator 200 ppm concentration of IBA rooting hormone was observed optimum for promoting macro-propagation in stem cuttings of lower diameter class (0.25-0.50 cm).

Plant Assemblages Along an Altitudinal Gradient in Northwest Himalaya

  • Gupta, Bhupendar;Sharma, Navneet
    • Journal of Forest and Environmental Science
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    • v.31 no.2
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    • pp.91-108
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    • 2015
  • The study investigates herbage communities along the altitudinal gradient in northwest Himalaya and highlights the effect of trees on its understory floristic diversity and phytosociology. The study was conducted in nine forests at three elevations viz., chir pine (Pinus roxburghii), mixed and khair (Acacia catechu) forests at elevation $E_1$ (850-1150 m), chir pine, mixed and ban oak (Quercus leucotrichophora) forests at elevation $E_2$ (1151-1600 m) and ban oak, mixed and chir pine forests at elevation $E_3$ (>1600 m) in a sub-watershed located in Solan district of Himachal Pradesh, India. These were compared grasslands located adjacent to forests. In all, 20 grass, 3 sedge, 2 forb and 4 legume species were recorded in study sites. Jaccard's coefficient of herbage vegetation was highest between chir pine forests and grasslands, and lowest in khair and ban oak forests. TWINSPAN dendrogram of herbage composition exhibited three subtypes with Apluda mutica, Arundinella nepalensis and Dichanthium annulatum as indicator species. Three groups of plant communities were identified on the basis of their moisture requirement. Peak density and basal area of herbage in forests and grasslands occurred by September. Density and basal area of herbage in grasslands at different elevations ranged from 649.6 to $1347.9tillers/m^2$ and 30.0 to $65.7cm^2/m^2$, respectively, while, in forests it varied from 351.2 to $1005.3tillers/m^2$ and 14.9 to $43.9cm^2/m^2$, respectively. Density and basal area of the herbage in plant communities decreased along the elevation. Under trees in forests the density of herbage decreased up to 77% and basal area up to 62% of their respective values in grasslands.

Environmental Factors Affecting the Abundance and Presence of Tree Species in a Tropical Lowland Limestone and Non-limestone Forest in Ben En National Park, Vietnam

  • Nguyen, Thinh Van;Mitlohner, Ralph;Bich, Nguyen Van;Do, Tran Van
    • Journal of Forest and Environmental Science
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    • v.31 no.3
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    • pp.177-191
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    • 2015
  • The effect of environmental variables on the presence and abundance of tree species in a tropical lowland undisturbed limestone and non-limestone forest in Ben En National Park, Vietnam was investigated. The relationships between 13 environmental variables and 29 tree species with a DBH ${\geq}10cm$, as well as between six 6 physical variables with 26 species of seedling and sapling communities were assessed by canonical correspondence analysis (CCA). Data concerning all tree species ${\geq}10cm$ DBH were collected from eighteen $400m^2$ sample plots, while the abundance of regeneration (all individuals ${\leq}5cm$ DBH) was counted in fifty $2{\times}20m$ strip-plots. The significance of species-environments correlations were tested by distribution-free Monte Carlo tests. The CCA of the 29 examined tree species and 13 environmental variables indicated that the presence and abundance of the tree species were closely related to topographic factors. We may confirm that soil properties including pH, soil moisture content, and soil textures, were the most crucial factor in tree species composition and their distribution. Several species including Pometia pinnata, Amesiodendron chinense, Gironniera cuspidate, Cinnamomum mairei, and Caryodaphnopsis tonkinensis were not controlled by soil properties and topographic variables. The CCA also indicated that the abundance of regeneration tree species at all sites had positive and significant correlations with soil depth, while the occurrence of several other tree species (such as Koilodepas longifolium and Aglaia dasyclada) was positively correlated with a higher slope and rocky outcrop.

Isolation and Characterization of a Gene Encoding Hexokinase from Loquat (Eriobotrya japonica Lindl.)

  • Qin, Qiaoping;Zhang, Lanlan;Xu, Kai;Jiang, Li;Cheng, Longjun;Xu, Chuanmei;Cui, Yongyi
    • Horticultural Science & Technology
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    • v.30 no.3
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    • pp.243-249
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    • 2012
  • Hexokinase is the first enzyme in the hexose assimilation pathway; it acts as a sensor for plant sugar responses, and it is also important in determining the fruit sugar levels. The full-length cDNA of a hexokinase gene was isolated from loquat through reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends, which was designated as EjHXK1. EjHXK1 is 1,839 bp long and contains an entire open reading frame encoding 497 amino acids. The predicted protein of EjHXK1 shares 72%-81% similarity with other plant hexokinases. Phylogeny analysis indicated that EjHXK1 is closely related to maize and rice hexokinases. Transient expression of the 35S: EjHXK1-GFP fusion protein was observed on the cell membrane and cytoplasm. Real-time RT-PCR indicated that EjHXK1 is expressed in loquat leaves, stems, flowers, and fruits. EjHXK1 transcripts were higher during early fruit development, but decreases before maturation, which is consistent with hexokinase enzyme activity during fruit development and conducive for hexose accumulation in mature fruits. These results imply that EjHXK1 may play important roles in the regulation of sugar flux during fruit ripening.

Wood Properties of Quercus acuta due to Thinning Intensity (붉가시나무의 간벌 강도에 따른 재질 특성)

  • Hong, Nam-Euy;Won, Kyung-Rok;Jung, Su-Young;Lee, Kwang-Soo;Byeon, Hee-Seop
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.6
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    • pp.721-729
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    • 2015
  • Wood properties depend on not only environmental factors such as soil, climate change, or forest stand characteristics, but also silviculture practices such as thinning, regeneration, or selection. This study report influences of the extent of thinning intensity from no thinning, moderate and heavy thinning to the wood property of Quercus acuta forest stands in Wan-do arboretum, Jeollanam-do Province. The results showed that there were close relationships between thinning intensity and anatomical, physical or mechanical properties of Quercus acuta wood. Especially, there are close relationships between thinning intensity and ring width or mechanical properties of wood. As a result, this study showed high correlations between Quercus acuta wood properties and thinning intensity of Quercus acuta forest stand. These findings are expected to be very useful as fundamental data for the implementation of silviculture practices of this specie to produce timber.

Forestry Profitability in Korea with Evaluating Stumpage Prices (입목가 평가를 통한 임업의 수익성 분석)

  • Min, Kyungtaek
    • Journal of Korean Society of Forest Science
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    • v.108 no.3
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    • pp.405-417
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    • 2019
  • We analyzed the profitability of Korea's forestry by evaluating stumpage prices of the main economic tree species. Stumpage prices are evaluated with a market value formula, subtracting logging and transporting costs from market prices of logs. If trees are sold at the current cutting age, the stumpage price of larch is about 4.5 million KRW per hectare and that of Korean pine is about 3.7 million KRW per hectare. The stumpage prices do not cover reforestation cost, which is about 6.1 million KRW per hectare. If government subsidies did not support the cost of reforestation and silviculture, there would be no profits at all. The cost of forestry is very high in terms of planting and silviculture. In the future, the prices of logs are not predicted to rise and the wages for labor are not predicted to fall. Without reforming the current forestry regime, Korean forestry is, thus, not sustainable. Therefore, low-cost forestry efforts like natural regeneration should be adopted to make forestry viable. Investments in forestry infrastructure like forest roads are also required to decrease the timber logging and transporting costs.

Input-Output Analysis Focused on Forestry and Wood Industry in Korea (임업·목재산업의 산업연관분석)

  • Min, Kyungtaek
    • Journal of Korean Society of Forest Science
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    • v.109 no.4
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    • pp.521-531
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    • 2020
  • In order to identify the economic impacts of forest-related industry on the national economy in general and the linkages between forestry and its related industries, an input-output analysis was conducted using the 2015 Input-Output Tables of the Bank of Korea. Production inducement effects are relatively high in paper products, lumber, and silviculture and relatively low in other wood industries. Value-added inducement effects are relatively high in silviculture and log production. With respect to the wood products industry, forward linkage effects are higher and backward linkage effects are lower. A Ritz-Spaulding multiplier analysis revealed that the growth of wood products production has only a modest impact on the growth of forestry. How to increase the linkage between forestry and the wood products industry is one of the most important policy tasks in Korea, given that it affects forest ecosystem management and climate change mitigation efforts.