• Journal of Forest and Environmental Science
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• v.36 no.1
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• pp.37-46
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• 2020

Vegetation carbon sequestration and regeneration are the two major parameters of forest research. In this study, we analyzed the vegetation carbon stock and regeneration of community-managed pine plantation of Kathmandu, central Nepal. Vegetation data were collected from 40 circular plots of 10 m radius (for the tree) and 1m radius (for seedling) applying a stratified random sampling and nested quadrat method. The carbon stock was estimated by Chave allometric model and estimated carbon stock was converted into CO₂ equivalents. Density-diameter (d-d) curve was also prepared to check the regeneration status and stability of the plantation. A d-d curve indicates the good regeneration status of the forest with a stable population in each size class. Diversity of trees was very low, only two tree species Pinus roxburghii and Eucalyptus citriodora occurred in the sample plots. Pine was the dominant tree in terms of density, basal area, biomass, carbon stock and CO₂ stock than the eucalyptus. The basal area, carbon stock and CO₂ stock of forest was 33±1.0 ㎡ ha^-1, 108±5.0 Mg ha^-1 and 394±18 Mg ha^-1, respectively. Seedling and tree density of the plantation was 4,965 ha^-1 and 339 ha^-1 respectively. The forest carbon stock showed a positive relationship with biomass, tree diameter, height and basal area but no relationship with tree density. Canopy cover and tree diameter have a negative effect on seedling density and regeneration. In conclusion, the community forest has a stable population in each size class, sequestering a significant amount of carbon and CO₂ emitted from densely populated Kathmandu metro city as the forest biomass hence have a potentiality to mitigate the global climate change.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.2
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• pp.97-106
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• 2006

Site index is an essential tool to estimate forest productivity. Generally, a site index equation is developed and used from the relationship between stand age and dominant tree heights. However, there is a limit to the use of the site index equation in the application of variable ages, environmental influence, and estimation of site index for the unstocked forest. Therefore, it has been attempted to develop a new site index equation based on various environmental factors including site, climate, and topographical variables. This study was conducted to develop a site index equation based on the relationship between site index and environmental factors for the species of Pinus koraiensis in Yangpyung-Gun, Gyunggi Province. The influence of climatic factors (temperature and solar irradiation ratio), topographical factors (elevation, slope, ratio of slope to valley and aspect) and soil profiles (soil depth by layer and soil consistency) on site index were evaluated by multiple regression analysis. Five environmental factors were selected in the final site index equation for Pinus koraiensis. The site index equation developed in this study was also verified by three evaluation statistics: model's estimation bias, model's precision, and mean square error of measurement. Based on the site index equation, the number of productive areas for Pinus koraiensis were estimated by applying GIS technique to digitized forest maps. In addition, the distribution of productive areas was compared with the areas of current distribution of Pinus koraiensis. It is expected that the results obtained in this study could provide valuable information about the amount and distribution of productive areas for Pinus koraiensis reforestation.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.4
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• pp.299-311
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• 2020

This paper analyzes the distribution of water vapor pressure and relative humidity in complex terrains by collecting weather observation data at 6 locations in the valley in Jungdae-ri, Ganjeon-myeon, Gurye-gun, Jeolla South Province and 14 locations in Akyang-myeon, Hadong-gun, Gyeongsang South Province, which form a single drainage basin in rural and mountainous regions. Previously estimated water vapor pressure used in the early warning system for agrometeorological hazard and actual water vapor pressure arrived at using the temperature and humidity that were measured at the highest density (1.5 m above ground) at every hour in the valley of Jungdae-ri between 19 December 2014 and 23 November 2015 and in the valley of Akyang between 15 August 2012 and 18 August 2013 were compared. The altitude-specific gradient of the observed water vapor pressure varied with different hours of the day and the difference in water vapor pressure between high and low altitudes increased in the night. The hourly variations in the water vapor pressure in the weather stations of the valley of Akyang with various topographic and ground conditions were caused by factors other than altitude. From the observed data of the study area, a coefficient that adj usts the variation in the water vapor pressure according to the specific difference in altitude and estimates it closer to the actual measured level was derived. Relative humidity was simulated as water vapor pressure estimated against the saturated water vapor pressure, thus, confirming that errors were further reduced using the derived coefficient than with the previous method that was used in the early warning system.

• Korean Journal of Environment and Ecology
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• v.27 no.2
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• pp.209-218
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• 2013

This study was conducted to analyze the characteristics of odonata communities as habitat types in Wonju City, Korea. The 33 plots were installed at 4 types of biotope like abandoned paddy fields, natural type reservoir, natural type river and forest valley in Wonju city. From the survey, the 9 family and 38 species were identified. As the result of comparative investigation of the species composition of each habitat through TWINSPAN analyzing, the difference of species composition was definite in abandoned paddy field, natural type reservoir and forest valley, however, it was uncertain in natural type river. The dominant species and the subdominant species of each habitat were mainly Sympetrum frequens and Sympetrum infuscatum but the distributions of Paracercion hieroglyphicum, Epophthalmia elegans, and Anax parthenope julius were different as haibtat types. The order of the index of species diversity was not different between abandoned paddy fiedls, natural type reservoir and natural type river, but forest valley was low. The abandoned paddy field was shown the most diverse spawning type of odonata, it is considered that hydrophyten play an important role in the abundant of odonata since the sorts of odonata spawning in plants are majority. As the result of analyzing interspecies relationship, Crocothemis servilia mariannae and Orthetrum albistylum, Crocothemis servilia mariannae-Platycnemis phyllopoda, Lyriothemis pachygastra-Sympetrum parvulum are shown the positive correlation, however, they have a difference in preferred habitat between high correlation species.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.73-82
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• 1988

This study was excuted to analyze the vegetational community structure of the Hongrudong valley the Mt. Gaya by three kinds of ordination techniques (polar, principal component analysis, reciprocal averaging). Eleven sites were sampled with the clumped method to analyze the vegetation structure. The result suggested that Hongrudong valley forest was divided by Pinus densiflora and Quercus aliena community. The relation between stand scores of ordination and soil pH, humus content, soil moisture had a tendency to increase significantly from P. densiflora to Q. aliena community. RA was the most effective method of this study. RA ordination was showed that successional trends of tree species seem to be from P. densijlora through Q. variabilis to Q. aliena, Carpinus laxiflora in the upper layer and from Lespedeza cyrtobotrva, Rhus spp., Rhododendron schlippenbachii through Fraxinus sieboldiana, Lindera obtusiloba to Euonymus oxyphyllus, Weigela subsessilis, Callicarpa japonica in the middle layer.

• Current Research on Agriculture and Life Sciences
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• v.23
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• pp.53-60
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• 2005

This study was carried out in order to produce useful material for the forest multiple use and forest protection management by soil physio-chemical analysis of studied area in Mt. Namsan. The result of soil physio-chemical analysis and statical analysis represented as following. In side of physical properties of forest soil in Mt. Namsan, Soil depth was average 31.4cm and available soil depth was average 20.0cm. Soil type was Brown forest soil that representative soil type in Korea. Soil texture was sandy loom(SL) except valley area. In side of chemical properties, the range of soil acidity was 4.29 ~ 5.19 (average 4.76), organic matter content was 3.17% that compared the lowest value to organic matter content of Korea forest soil. Available phosphorus was 3.64ppm that was lower than others forest soil. Exchangeable cation content was similar to the Korea brown forest soil. Cation exchange capacity(CEC) was $8.22cmol_c/kg$ in Mt. Narnsan.

• Journal of Forest and Environmental Science
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• v.39 no.1
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• pp.13-19
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• 2023

We investigated Soil respiration in Bluepine forest of western Bhutan, in relation to soil temperature, moisture content and soil pH and it was aimed at establishing variability in space and time. The Bluepine forest thrives in the typical shallow dry valleys in the inter-montane Bhutan Himalaya, which is formed by ascending wind from the valley bottom, which carries moisture from the river away to the mountain ridges. Stratified random sampling was applied and the study site was classified into top, mid, low slope and further randomized sample of n=20 from 30 m×30 m from each altitude. The overall soil respiration mean for the forest was found 2248.17 CO₂ g yr^-1 and it is ~613.58 C g yr^-1. The RS from three sites showed a marginal variation amongst sites, lower slope (2,309 m) was 4.64 μ mol m^-2 s^-1, mid slope (2,631 m) was 6.78 μ mol m^-2 s^-1 and top slope (3,027 m) was 6.33 μ mol m^-2 s^-1 and mean of 5.92 μ mol m^-2 s^-1, SE=0.25 for the forest. Temporal distribution and variations were observed more pronounced than in the space variation. Soil respiration was found highest during March and lowest in September. Soil temperature had almost inverse trend against soil respiration and dropped a low in February and peak in July. The moisture in the soil changed across months with precipitation and pH remained almost consistent across the period. The soil respiration and soil temperature had significant relationship R²=-0.61, p=0.027 and other variables were found insignificant. Similar relationship are reported for dry season in a tropical forest soil respiration. Soil temperature was found to have most pronounced effect on the soil respiration of the forest under study.

• Journal of Environmental Science International
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• v.11 no.11
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• pp.1149-1156
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• 2002

The ecological characteristics of Dolbae trees, a valuable genetic resource for native pyrus fruit trees, were investigated at four naturally inhabited areas on Mount Kaya, Gyeongsangnam-Do. Most Dolbae trees were found on the southwest side of an old hiking path to a mountain valley at altitudes of 610∼670 m. The surrounding flora consisted of 46 families, 69 genera, 75 species, and 10 varieties. The natural habitat of the Dolbae trees was basically a deciduous broad-leaved forest with a predominance of Quercus serrata and ligneous plants(xylophytes) from the Fagaceae and Betulaceae families. The habitat was also found to be in a second transition resulting from forest disturbance and exhibited a degree of diversity of 2.901-5.065, based on Shannon-Weiner's index. Examination of the Dolbae trees found in Mount Kaya revealed diameter breast heights(DBHs) ranging from 10 to 60 cm, including six old and large Dolbae trees with a DBH of 50∼60 cm, which will be particularly valuable as a genetic resource. Accordingly, the current results suggest that the study areas are a secondary forest in a typical mid-temperate zone resulting from forest damage about 10 years earlier.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.32-42
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• 1988

This research was to establish the fundamental materials for the preservation and multiple-purpose management of forest vegetation of Dong Hwa Sa area located in the south facing slope of Mt. Pal-Gong. Analysis of forest vegetation of this area was studied by the method of Gentaro Toyohara, based on ZM School method and Pfister. The results obtained were summarized as follows. (1). Forest vegetation in this area divided into mountain forest and valley forest. (2). Mountain forest divided into A. Pinus densiflora community, B. Carpirtus laxiflora community, C. Quercus mongolica community. (3). Valley forest was formed mostly of Zelkova serrata community. (4). Piraus densiflora community divided into 1. Pines densiflora typical group, 2. Pines densiflora-Alnus hirsuta group, 3. Pines densiflora-Ilex macropoda group. (5). Quercus mongolica community divided into 1. Pinus densiflora-Carpinus cordata group, 2. Prunus sargentii-Hydrangea serrata for. acuminata group, (6). Zelkova serrata community divided into 1. Acer mono group, 2. Vine plant group. A vegetation analysis based on concepts and methods developed by Robert, D. Pfister and Gentaro Toyohara was considered to be effective on providing a guiding principle for a multiple-purpose management of forestry and a three-dimensional utilization of forest, but it is not easy for us to utilize such a analysis method because we are not rich in the materials of analysis of vegetation to our forest. Thus, It is necessary that we should collect much materials to various parts of forest in order that may utilize this method of analysis of vegetation.

• Korean Journal of Plant Resources
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• v.18 no.2
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• pp.223-239
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• 2005

The vascular plants collected from Dongwol Valley in Mt. Gyeryongsan, national park were composed of all 248 taxa including cultivated species, and classified into 1 phylum, 4 classes, 3 subclasses, 34 orders, 84 families, 178 species, 33 varieties and 4 forms. As compared the flora of the commonly distributing species of this region with those of the southern part, the middle part, the northern part of the Korean Peninsula, Jeju-do Island and Ulreung-do Island, the proportion of them were $90.3\%,\;98.0\%,\;79.0\%,\;73.8\%$ and $62.1\%$, respectively. One taxon of the plants distributed only in the southern part, 3 taxa of those in the middle part, 5 taxa of those in the middle-northern part and 23 taxa of those in the middle-southern part were found in this Valley. Natural resource plants were categorized into edible 118 taxa, medicinal 78 taxa, industrial 46 taxa, ornamental 39 taxa, timber 14 taxa and fiber 9 taxa. Four taxa of the Korean endemic plants are distributed in Dongwol Valley. The vegetation of the valley is Quercus and Rhododendron mixed forest, and it belongs to the boundary between the middle part and the southern part in the floral zone of the Korean Peninsula.