• Journal of Ecology and Environment
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• v.43 no.1
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• pp.84-84
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• 2019

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.1
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• pp.53-69
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• 2015

Plants and birds have symbiotic relationship as the birds eat the fruits and disperse its seeds from the different places. Because Brown-eared Bulbul eats various fruits, We investigated the fruits consumed by Brown-eared Bulbul and the distribution of these seeds. Surveys were conducted at several area throughout Jeju Island at least twice a month from 2013 to 2014. We identified the fruits consumed by Brown-eared Bulbul through observation, pictures and interviews from the local residents. Results showed that this species consumed fruits from 82 plant species, belonging to 38 plant families. Thirty nine percent(39%) of these plant species belong to the Rosaceae, Lauraceae, Moraceae, Aquifoliaceae and Vitaceae and 33 species were classified as warm-temperate and subtropical plant which is 40% of the total plant species consumed. Two feeding types, which were gulper type and pecking type were observed for the Brown-eared Bulbul. It was also observed that this species preferred eating fruits of gulping type compared to that of pecking type. The average size of the fruits consumed through gulping was $8.92{\pm}3.41mm$ while it was $45.25{\pm}26.67mm$ for the pecker type. This bird species also consumed more fruits with globular shape compared to those of fruits with ellipse shape. For the fruit color, red and black-colored fruits were more preferred than yellow-colored fruits by Brown-eared Bulbul. Eaten frequency varied from 0.04 to 0.58 and the 10 fruits species were eaten frequently by Brown-eared Bulbul. This study would provide information for the role of Brown-eared Bulbul in the ecosystem as a seed dispersal agent.

• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.131-142
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• 2024

The purpose of this study was to estimate the optimal stand density criteria for each growth stage of Chamaecyparis obtusa (Siebold & Zucc.) Endl. to achieve the timber production goal for cypress forests and develop an optimal silvicultural system for forest thinning. A relative yield index (Ry) value of 0.75, presented as a stand density management criterion index, was estimated by analyzing the relationship characteristics between the composition ratio and stand density of slender trees from 216 sample plots of the recruited cypress forests. The analysis of the feasibility of achieving each production target in the existing silvicultural system for C. obtusa revealed that the growth rate according to the parameters of forest land productivity, such as site index and thinning intensity according to the increase in age, was not properly reflected. In the thinning system for each timber production target analyzed in this study, 353 high-quality large hardwoods from 498.1 m³/ha, 703 high-quality medium hardwoods from 376.2 m³/ha, and 1,758 small-diameter hardwoods from 249.5 m³/ha could be harvested. Although the silvicultural system prepared on the basis of the results of this study cannot be uniformly applied according to various management goals, this study is meaningful in that it presents empirical reference standards based on the stand density management diagram that reflects the growth characteristics of cypress forests in South Korea.

• Journal of the Korean Wood Science and Technology
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• v.49 no.5
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• pp.482-490
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• 2021

This research was conducted to analyze the sound absorption effect of air-dried leaves from two evergreen tree species found in Korea's warm-temperate and subtropical regions. As eco-friendly sound absorption materials, Dendropanax morbiferusa, and Fatsia japonica leaves were prepared in three specimen units sizes 0.5 × 0.5 cm², 1.0 × 1.0 cm², and 2.0 × 2.0 cm², and each of them was formed at a thickness of 1.00 cm, 1.75 cm, and 2.50 cm. The measured sound absorption coefficients (SAC) for 18 conditions were comparatively analyzed in this study. The SAC of both tree species was significantly improved by increasing the dried leaf layer thickness. These results showed a more consistent and distinct trend for both tree species under the condition of 0.5 cm² in dried leaf size compared to other leaf specimen sizes. However, as the thickness increased, the difference in sound absorption effect according to the leaf size tends to decrease overall. In the case of D. morbiferus, there was no significant difference in SAC based on leaf size under the condition of 2.5 cm thickness (p < 0.05). The highest mean SAC was found in a 2.5 cm thick condition with a leaf size of 0.5 × 0.5 cm², 0.549 for D. morbiferusa, and 0.594 for F. japonica, respectively.

• Journal of Korean Society of Forest Science
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• v.112 no.4
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• pp.417-425
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• 2023

The aim of this study was to derive stem taper equations for Quercus acuta, one of main evergreen broad-leaved tree species found in warm temperate regions, and to prepare a stem volume table using those stem taper equations. A total of 688 individual trees were used in the analysis, which were collected from Jeonnam-do, Gyeongnam-do, and Jeju-do. The stem taper models applied to derive the stem curve pattern were the Max and Burkhart, Kozak, and Lee models. Among the three stem taper models, the best explanation of the stem curve shape of Q. acuta was found to be given by the Kozak model, which showed a fitness index of 0.9583, bias of 0.0352, percentage of estimated standard error of 1.1439, and mean absolute deviation of 0.6751. Thus, the stem taper of Q. acuta was estimated using the Kozak model. Moreover,thestemvolumecalculationwasperforme d by applying the Smalian formula to the diameter and height of each stem interval. In addition, an analysis of variance (ANOVA) was conducted to compare the two existing Q. acuta stem volume tables (2007 and 2010) and the newly created stem volume table (2023). This analysis revealed that the stem volume table constructed in the Wando region in 2007 included about twice as much as the stem volume tables constructed in 2010 and 2023. The stem volume table (2023) developed in this study is not only based on the regional collection range and number of utilized trees but also on a sound scientific basis. Therefore, it can be used at the national level as an official stem volume table for Q. acuta.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.5
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• pp.43-49
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• 2014

Fairy Pittas use the forest around the valley and Gotjawal as breeding places. This survey was conducted to investigate the characteristic of earthworms, specifically its population density, body size around the breeding site in Gotjawal and the forest around the valley areas from the middle of July to the end of July 2013. A total of 405 individual earthworms were collected in the 100 small established quadrats, in which 315 were found in Gotjawal and 90 were found in the forest around the valley area. The density of earthworms in Gotjawal was significantly higher compared to that forest around the valley area. It was also observed that the body size of earthworms was significantly different between Gotjawal and the forest around the valley area. Proportion of number of individuals which are larger than 7cm in body size was 43%(n=135) in Gotjawal and 84%(n=76) in the forest around the valley area, respectively. Soil area was not important factor to the density of earthworms. We suggest that Gotjawal can be considered as a suitable breeding site for Fairy Pitta because of the richness of its primary food in this area.

• Korean Journal of Environment and Ecology
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• v.16 no.2
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• pp.131-140
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• 2002

The bryophyte communities on the forest floor of the mixed coniferous and deciduous broad-leaved forest of cool temperate zone on Deongnyusan(1,616m) south-eastern part of the Korean Penninsula were investigated from the phytosociological viewpoint. As a result, a bryophyte community was recognized, considering the phytosociological unit of the forest: Sasamorpha borealis-Abies koreana / Hylocomiopsis ovicarpa-Thamnoblyum alopecurum community. This community was interpreted as a counterpart one of the Sasamorpha borealis-Abies koreana / Dicranum scoparium-Plagiothecium silvaticum community in the Jiri Mountains, but between the two communities, the species composition was somewhat different. The bryophyte community on the forest floor on Deongnyusan was confirmed as a synusie belonging to the Fraxino-Abietetum koreanae Song 1988. Up to date many investigators have described the coniferous forest distributed above 1,400m on Deongnysan as the forest vegetation of subarctic(=subalpine) zone. However, from the results of the present study, the forest vegetation, a mixed forest, was elucidated to be one of cool temperate zone. Species diversity of the terri-colous bryophyte community on Deongnyusan was very close to that of the communities of the similar type in the Jiri Mountains. The taxa of the bryophyte community was composed of 19 families,25 genera and 38 species.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.1
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• pp.94-105
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• 2016

This study was carried out to assess the distributional probability for Evergreen Broad-Leaved Forests(EBLFs) using the field data and digital climate data that were occurred during the period of 1980 to 2010. For the validation of logistic regression model, the probabilistic value ranged from 33 to 84%, especially the probabilistic value of growing distribution becomes lower patterns with higher altitude. In addition, it has been estimated that the probabilistic value of growing distribution is the highest with 63~83% among the regional units in temperate/warm-temperate forests.

• Journal of Forest and Environmental Science
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• v.35 no.1
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• pp.6-24
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• 2019

We have investigated the impact of anthropogenic and natural disturbances on regeneration, composition and diversity in some temperate forests of Bhagirathi Catchment Area of Garhwal Himalaya. The forests were categorized on the basis of canopy cover and magnitude of disturbance into highly, moderately and least disturbed classes. The dominant tree species at lower elevation were Pinus roxburghii and Quercus leucotrichophora, while Abies pindrow, Q. semecarpifolia and Rhododenron arboreum were the dominant species at the upper elevational forests. Cythula tomentosa and Indegophera heterentha were the dominant shrub species present in all the forests. Similarly, Circium wallichii and Oxalis corniculata were the dominant herb species found in all forests (except Q. leucotrichophora forest), whereas Thalictrum foliolosum and Viola pilosa were noticed in each forest (except P. roxburghii forest). The tree density values oscillated between $400{\pm}10\;trees\;ha^{-1}$ to $750{\pm}89.1\;trees\;ha^{-1}$ which generally decreased from lower to higher disturbance regimes however, the total basal cover value was highest ($88.1{\pm}23.6m^2\;ha^{-1}$) in highly disturbed forest and lowest ($25.8{\pm}2.2m^2\;ha^{-1}$) in moderately disturbed forest. The shrub and herb densities were maximum in least disturbed forest, while the young regenerating individuals i.e., sapling and seedling were observed increasing from high to low disturbed forests which reflected that the forest fragmentation adversely affected the regeneration. However, A. pindrow and P. roxburghii were found invariably encroaching the habitats of R. arboreum and Q. leucotrichophora at various altitudes, respectively. The Canonical Correspondence Analysis clearly indicated that the elevation and lopping intensity have more impact on trees, while shrub and herbs were more influenced by elevation, canopy cover, light attenuation and soil erosion. Pinus roxburghii was the only species which was affected by heavy litter removal and forest fire.

• Journal of the Korean Wood Science and Technology
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• v.48 no.5
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• pp.631-640
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• 2020

In this study, the effect of specimen size and layer thickness on the sound absorption of the leaves of two evergreen broad-leaved tree species, Dendropanax morbiferus and Fatsia japonica, was investigated. The specimen sizes of 0.5 × 0.5, 1.0 × 1.0, and 2.0 × 2.0 ㎠ and layer thicknesses of 1.00, 1.75, and 2.50 cm were considered. At the layer thickness of 2.5 cm, the leaf of the D. morbiferus showed no significant difference in sound absorption coefficients (SACs) as the sample size varied, however, a significant change in SACs was recorded in that of the F. japonica. At 1.0-cm thickness, the SACs of the F. japonica leaf varied more remarkably with the sample size. The 2.50-cm-thick F. japonica leaf with the specimen size 0.5 × 0.5 ㎠ exhibited the highest sound absorption effect among all samples investigated.