• Journal of Korean Society of Forest Science
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• v.107 no.3
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• pp.278-286
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• 2018

This study examined the damage characteristics through investigation for a total of 10 factors (longitudinal position, crossing position, soil type, collecting well volume, outlet position, water apron material, waterway existence, pipe culvert diameter, pipe culvert gradient, pipe culvert height) affecting outlet damages of forest road cross drainage for forest roads in the Research Forest of Kangwon National University. We predicted outlet damages of forest road cross drainage for forest roads using a discriminant analysis Results showed that longitudinal position, crossing position, soil type and pipe culvert height did not affect damages caused to forest road cross drainage. Most influential factors affecting outlet damages were outlet position, waterway existence, pipe culvert diameter, pipe culvert gradient and collecting well volume, respectively. The discriminant ratio calculated from the developed discriminant function was 68.8% which is reasonably reliable.

• Journal of Korea Foresty Energy
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• v.25 no.2
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• pp.1-8
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• 2006

The physical, mechanical and chemical properties of old and new Korean red pine (Pinus densiflora) were analyzed. The old woods were from dismantled timbers of Bonjungsa temple. The crystallized resin in the latewood was observed by microscopic analysis. Also, reduction of specific gravity, occurrence of microscopic cleavage of tracheid was observed in the old wood. The angle of microscopic cleavage of tracheid is estimated with the same angle of micro-fibril angle of 52 layer. The bending, compression and shear strength of old world were decreased about 35-27% than those of new wood. Dynamic modulus of elasticity measured by ultrasonic nondestructive test has the tendency of reducing by the time elapse of the wood usage. Therefore, deterioration of wood could be measured by reduction of specific gravity and dynamic MOE. The static MOE and mechanical properties of old wood could be predictable by measuring dynamic MOE in the longitudinal direction. Extractives of the old wood in 1-% NaOH solution are larger quantity than new wood. Therefore the decay of the wood could be evaluated by analyzing the chemical compound, especially 1-% NaOH solution. The results of this research could be used for understanding and prediction of the changing properties with elapsing time of wood.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.3
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• pp.190-200
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• 2022

In this study, the island's land-use and land-cover change (LULCC) is analyzed in South Korea using remotely sensed land cover data(Globeland 30) acquired from 2000 to 2020 to meet the requirement of providing practical information for forest management. Analysis of LULCC between the 2000 and 2020 images revealed that changes to agricultural land were the most common type of change (7.6% of pixels), followed by changes to the forest (5.7%). The islands forests maintain 157,246 ha (42.2% of the total island area). Land cover types that changed to the forest from grasslands were 262 islands, while reverse cases have occurred on 421 islands. These 683 islands have a possibility of transition and disturbance. The artificial land class was newly calculated in 22 islands. The forests, which account for 42.2% of the 22 island area, turned into grassland, and 27.8% of agricultural land and grassland turned into forests. The development of artificial land often affects developed areas and surrounding areas, resulting in deforestation, management of agriculture, and landscaping. This study can provide insights concerning the fundamental data for assessing ecological functions and constructing forest management plans in islands ecosystems.

• Journal of Ecology and Environment
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• v.43 no.2
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• pp.85-97
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• 2019

Background: Despite the increasing role of dry forests in climate change adaptation and mitigation, these versatile resources has got less attention in the national and regional planning, their potential to enhance the local and national economy has been overlooked, and their contribution to sustainable environmental management has not been recognized. Hence, the objective of this study was to assess the socioeconomic contribution of dry forests and forest products to climate change adaptation in the Liben Woreda, Southern Oromia region of Ethiopia. Methods: For this study, an integrated qualitative and quantitative approach was used. A total of 74 households from villages in the Bulbul, Boba, and Melka-Guba kebeles were randomly selected for the household survey. Results: Results showed that 75% of the respondents in the area indicated that climate change has become their major sources of vulnerability, where drought has been manifested in the form of crops failure and massive death of livestock particularly cattle species. The main income strategies of the study households include livestock, crop, forests such as gum and resins, firewood and charcoal and non-farm activities such as in the form of petty trade, wage and aid. The average total household income was ETB 11,209.7. Out of this, dry forest income constituted 15% of the total income. In addition to using dry forests as rangeland for livestock, the communities collect wood for construction, fodder, traditional medicine, and forest food both for subsistence and for sale. On the other hand, dry forest products could be considered as less vulnerable, rather resilient livelihood strategies to climate- and environment-related risks compared to livestock and crop production such as in the face of drought periods. More than 48.6% of the households argued that the income generated from dry forests increased substantially due to increment in the level of engagement of family members in forest based income activities. On the other hand, 35.8% of the households responded that livestock production, particularly camels and goats, have been making the livelihood strategies of the respondents more resilient indicating the shift made from grazers browsers to livestock. In general trends show that, the trends of livelihood dependency on dry forest were highly increasing indicating the importance of dry forest income in responsse to frequent droughts. Conclusions: Dry forest income has been becoming crucial livelihood staretgy in response to frequent droughts in the study area and hence, it is important to improve the management of dry forests for livelihood enhancement, while also securing their long-term ecological functions.

• Journal of Korean Society of Forest Science
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• v.105 no.3
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• pp.342-350
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• 2016

This study aims to make the stand density management diagram which is very useful for establishing systematic management plan and obtaining management goal in Pinus densiflora forest. To estimate 5 models mainly composed of stand density management diagram, we used total of 1,886 sample plots having more than 75% of the total basal area of the pine trees in each stand. To test the goodness of fit, $X^2$ was computed with a significance level of 5%, and the acceptable error range as 20%. Also standard deviation of the model was $34.59m^3{\cdot}ha^{-1}$, minimum acceptable error range was 16.59% and coefficient of variation was 22.11%. If we use the stand density management diagram, it would be useful to establish the timber yield and thinning plan understanding the pathway of stand density management.

• Journal of Korean Society of Forest Science
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• v.106 no.4
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• pp.457-464
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• 2017

This study has utilized the stand density management diagram to devise an efficient management standard for the stand density for Pinus densiflora that secures the health of the stands and predicted the harvest goals. The appropriate stand control level was estimated by modeling the relationship of the relative yield index (Ry) to the ratio of slender trees within the stand through an exponential function; the coefficient of determination ($R^2$) was found to be 0.424 according to the estimation. The ratio of slender trees within the stand showed a tendency of rapid increase at a certain relative yield index; with this relational function, the appropriate Ry value of 0.84 was obtained. By estimating the curve of the Ry value 0.84, which was the appropriate stand density management level, as well as the height of dominant trees in the central region of Korea, the production objective for each site index was set. Assuming that the final age by the site indices ranged from 10 to 16 for the P. densiflora in central region of Korea, the number of production was estimated to be between 426 to 1,311 trees per ha. It was predicted that the production of medium-diameter logs larger than 30 cm in diameter is possible for the target DBH at a site index of more than 16; small-diameter logs larger than 20 cm in diameter for site indices 12 and 14 enabled, and small-diameter logs of less than 20 cm for site index 10.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.163-163
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• 2003

The study area, Kwangneung Experiment Forest (KEF) is located on the west-central portion of Korean peninsula and belongs to a cool-temperate broadleaved forest zone. At the old-growth deciduous forest near Soribong-peak (533.1m) in KEF, we have established a permanent plot and a flux tower, and the site was registered as a KLTER site and also a KoFlux site. In this study, we aimed to present basic ecological characteristics and synthetic data of carbon budgets and flows, and some monitoring data which are essential for providing important parameters and validation data for the forest dynamics models or biogeochemical dynamics models to predict or interpolate spatially the changes in forest ecosystem structure and function. We made a stemmap of trees in 1 ha plot and analyzed forest stand structure and physical and chemical soil characteristics, and estimated carbon budgets by forest components (tree biomass, soils, litter and so on). Dominant tree species were Quercus serrata and Carpinus laxiflora, and accompanied by Q. aliena, Carpinus cordata, and so on. As a result of a field survey of the plot, density of the trees larger than 2cm in DBH was 1,473 trees per ha, total biomass 261.2 tons/ha, and basal area 28.0 m2/ha. Parent rock type is granite gneiss. Soil type is brown forest soil (alfisols in USDA system), and the depth is from 38 to 66cm. Soil texture is loam or sandy loam, and its pH was from 4.2 to 5.0 in the surface layer, and from 4.8 to 5.2 in the subsurface layer. Seasonal changes in LAI were measured by hemispherical photography at the l.2m height, and the maximum was 3.65. And the spatial distributions of volumetric soil moisture contents and LAIs of the plot were measured. Litterfall was collected in circular littertraps (collecting area： 0.25m2) and mass loss rates and nutrient release patterns in decomposing litter were estimated using the litterbag technique employing 30cm30cm nylon bags with l.5mm mesh size. Total annual litterfall was 5,627 kg/ha/year and leaf litter accounted for 61% of the litterfall. The leaf litter quantity was highest in Quercus serrata, followed by Carpinus laxiflora and C. cordata, etc. Mass loss from decomposing leaf litter was more rapid in C. laxiflora and C. cordata than in Q. serrata litter. About 77% of C. laxiflora and 84% of C. cordata litter disappeared, while about 48% in Q. serrata litter lost over two years. The carbon pool in living tree biomass including below ground biomass was 136 tons C/ha, and 5.6 tons C/ha is stored in the litter layer, and about 92.0 tons C/ha in the soil to the 30cm in depth. Totally more than about 233.6 tons C/ha was stored in DK site. And then we have drawn a schematic diagram of carbon budgets and flows in each compartment of the KEF site.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.331-337
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• 2013

Formate dehydrogenase (FDH), catalyzing the oxidation of the formate ion to carbon dioxide, is known as the stress protein in response to drought, low temperature and pathogen infection. To study the functions of FDH in poplar (Populus alba ${\times}$ P. glandulosa), we isolated a FDH cDNA (PagFDH1) and examined its expressional characteristics. The PagFDH1 is 1,499 base pairs long and encodes a putative 388 amino acid protein with an expected molecular mass of 42.5 kDa. The PagFDH1 protein has N-terminal mitochondria signal peptide and $NAD^+$ binding domain. Southern blot analysis indicated that a single copy of the PagFDH1 is present in the poplar genome. PagFDH1 is expressed highly in the suspension cells (especially in the lag and early exponential phases) and moderately in roots, flowers and leaves. ABA-mediated enhanced expression of PagFDH1 in response to drought and salt stress treatments indicates that the gene product could play an important role in the development of stress resistant trees.

• Journal of Korean Society of Forest Science
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• v.99 no.6
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• pp.929-933
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• 2010

According to the IPCC guideline (2006), uncertainty assessment is very important in terms of the greenhouse gas inventory. Therefore, the purpose of this study is to estimate the basic wood density (BWD) and its uncertainty for Pinus densiflora in Korea. In this study, Pinus densiflora forests were divided into two ecotypes which were Gangwon and Jungbu regions. A total of 33 representative sampling plots was selected to collect sample trees after considering the tree ages and DBH distributions. The BWD showed statistically no difference between age classes based on IPCC's classification. While, it showed statistically difference(pvalue=0.0017) between eco-types. The BWD and uncertainty was 0.396(g/$cm^3$) and 12.9(%) for Pinus densiflora in Gangwon, while it was 0.470(g/$cm^3$) and 3.8(%) for Pinus densiflora in Jungbu. The values of the BWD uncertainty for Pinus densiflora were more precised than the values given by the IPCC guideline.

• Journal of Korean Society of Forest Science
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• v.95 no.1
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• pp.124-130
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• 2006

To explore the development of photoprotective mechanisms, chlorophyll a fluorescence, chlorophyll and carotenoid content and antioxidant enzyme activity in leaves were investigated at different vitality and leaf development stage of Alnus firma Sieb. et Zucc under tailing condition. The lowest maximum photochemical efficiency (Fv/Fm) in leaves of high- and low-vitality plants were observed at 12:00 pm and 2:00 pm, respectively, and the decrease of Fv/Fm in leaves of all plants were almost completely restored at 6:00 pm. Fv/Fm of full-expansion leaves was higher than that of emergence leaves at all measurement time. Chlorophyll, ${\beta}$-carotene and xanthophyll content in leaves of high-vitality plants and in full-expansion leaves were higher when compared to those of low-vitality plants and emergence leaves. Especially xanthophyll contents in both stage leaves of high-vitality plants were higher than 8.7 times and 18.8 times those of low-vitality plants. Only SOD activity was seen significant difference between leaf stage in leaves of high-vitality plants.