• Korean Journal of Environment and Ecology
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• v.28 no.2
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• pp.205-214
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• 2014

The purpose of this study is to suggest vegetation management method as the cultural landscape forest of Dongbaek Island which is the district monument. The study area was $20,000m^2$ around the peak area in management as the nature sabbatical area. Vegetation structure type was classified with the criteria of topography, vegetation, management and the management plan was derived from the vegetation structure analysis according to the types. Vegetation structure types were Management-Camellia japonica, Non-management-Eurya japonica, Non-management-Rugged area-Eurya japonica. As the result of vegetation structure, Pinus thunbergii dominated in canopy layer and Camellia japonica and Eurya japonica dominated in Type I and in Type II and III, respectively. Especially, Machilus thunbergii as the climax species in the warm temperate forest were distributed centering shrubs, and as the result of distribution of diameter of breast height, middle size of Celtis sinensis and Machilus thunbergii were distributed in type I, II. Machilus thunbergii were distributed in range of 4 to 44 individuals through the all types. Mean age of canopy layer was 66 year-old and sub-canopy layer was 22.9 year-old. Shanon's species diversity was analysed from 0.5472 to 0.8646. As the vegetation management direction of Dongbaek island, managed Camellia japonica forest was suggested to maintain the regular management and non-managed Eurya japonica forest was required to remove the Eurya japonica and plant the Camellia japonica. In case of non managed Eurya japonica forest in rugged area, vegetation succession was required to laurel forest.

• Journal of Forest and Environmental Science
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• v.22 no.1
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• pp.18-26
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• 2006

The study was carried out to investigate the flora and stand structure in southwest slope of Mt. Chukryoung from March to October, 2005. As a result of that, vascular plants were 87 families, 268 genera, 399 species, 1 subspecies, 53 varieties, 4 formae and 457 taxa in all: Korean endemic plants were 11 families, 14 genera, 14 species and 14 taxa in all: rare or endangered plants were 8 families, 12 genera, 13 species and 13 taxa in all: naturalized plants were 8 families, 14 genera, 15 species, 1 varieties and 16 taxa in all. The stand structure analysis showed that: canopy was covered with Quercus mongolica. sub-canopy was covered with Styrax obassia, Euonymus oxyphyllus, Acer pseudo-sieboldianum and Quercus mongolica.

• Korean Journal of Environment and Ecology
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• v.21 no.1
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• pp.47-54
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• 2007

This study was conducted to clarify the characteristics of habitat structure and bird communities between natural deciduous forest and around the road from October 2005 to August 2006 in the National Arboretum, Gwangneung, Korea. There were more larger trees and higher coverage of crown canopy in the natural deciduous forest than around the road. A total thirty seven species of birds were observed in the natural deciduous forest and twenty species were around road. The observed number of bird species and individuals, and bird species diversity index (H') were higher in the natural deciduous forest in each season. Foraging and nesting guild structures were also different. The differences of characteristics of bird communities would be related with habitat structure between both study areas.

• Korean Journal of Plant Resources
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• v.33 no.5
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• pp.482-500
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• 2020

The purpose of this study was to identify the phytosociological vegetation structure through a sampling survey of Mt. Jirisan National Park. And it was conducted to provide the latest data for establishing a conservation and management plan for forest ecosystems. As a result of TWINSPAN classification, it was classified into 4 communities. Group I is the Fraxinus mandshurica - Acer pseudosieboldianum Community, group II is the Quercus serrata - Quercus variabilis Community, group III is the Quercus mongolica Community, group IV is the Pinus densiflora Community. Group I is dominated by Fraxinus mandshurica in the canopy layer, and Cornus controversa and Quercus mongolica compete and maintain dominance. Group II is dominated by Quercus variabilis and Quercus serrata in canopy layer, and Styrax obassia and Styrax japonicus compete in sub-tree layer. In group III, Quercus mongolica has a high dominance of 67% in canopy layer and 27% in the sub-tree layer, and Acer pseudosieboldianum competes with the Quercus mongolica in the sub-tree layer. In group IV, Pinus densiflora showed a high dominance of 74% in canopy layer. The sub-tree layer is dominated by Quercus mongolica, and is accompanied by competition between Carpinus tschonoskii and Fraxinus sieboldiana.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.3
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• pp.262-269
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• 1994

This study was conducted to clarify high yielding factors of F$_1$ hybrids in terms of the growth characteristics, canopy structure, nitrogen content and nitrogen profile in the canopy. Varieties used in this study were four hybrid rices showing different heterosis in grain yield and their parents. Varieties of Japonica were Reimei (maintainer), TP 681 and TP 1278(restorers), and F$_1$ (Reimei ms ${\times}$ TP 681, Reimei ms ${\times}$ TP 1278) hybrid rices. Those of Indica type were 1378 (maintainer), Milyang 46 and Suweon 287(restorers), and F$_1$ (1378 ms ${\times}$ Milyang 46, 1378 ms ${\times}$ Suweon 287) hybrid rices. High heterosis in F$_1$ hybrid rices were shown in panicles per hill and spikelets per panicle, being greatest in spikelets per panicle. Spikelets per square meter expressed even greater heterosis than those two yield components because of multiplicative effect of them. Heterosisof ripened concentration of leaf nitrogen and steeper gradient of leaf nitrogen in canopy strata but also better productive structure in favor of light interception seemed to have led to higher canopy photosynthesis of F$_1$ hybrids and subsequent higher partition of assimilates for leaf area expantion especially during vegetative growth stage. Higher dry matter production, resulting from these factors, during vegetative stage would have contributed to the production of greater number of spikelets per square meter, and consequently to higher grain yield in F$_1$ hybrids.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.4
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• pp.325-334
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• 2006

Understanding the airflow characteristics within the canopy structure installed between closely adjacent tunnels either for light adaptation or for protection from snow hazards is required for the normal ventilation as well as safety system design. Grade, horizontal alignment, cross-sectional area and shape are known to substantially influence the fire smoke behavior and their influences raise great concern for the safety design. This paper aims at studying the effects of tunnel geometrical characteristics and canopy installation on the ventilation and fire propagation through CFD analysis. In the case of 145m long canopy, 50% opening ratio is preferred with respect to the airflow pattern and ventilation efficiency. When a 20MW fire occurs in a 1.8km-long tunnel and four 1250mm reversible jet fans are instantly turned on, smoke concentration at 40m downstream of the fire decrease 13% for the upgrade tunnel with 2% gradient and increases 20% for -2% gradient, compared to the standard horizontal tunnel. Backlayering is observed within 45m-long segment toward the entrance in 2% down-graded tunnel. In a rectangular tunnel, there is no significant difference of smoke concentration as well as velocity profile from the standard crown tunnel. Three-laned tunnel shows lower level of both profiles and backlayering is detected up to 50m upstream of the fire, while the risky situation rapidly disappears thereafter.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.4
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• pp.37-49
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• 2015

The goal of this research is to examine air temperature changes according to tree type, plantation type, roadside green area structure, and green volume of street green area within a city. The plantation type that could be analyzed for comparison by tree type with over 3 species was 1 rows of tree+shrubs. The results of analysis of average air temperature difference between pedestrian and car streets vis-a-vis 1 row of tree+shrub in high air temperature areas were: Pinus densiflora, $1.35^{\circ}C$; Zelkova serrata, $1.84^{\circ}C$; Ginkgo biloba, $2.00^{\circ}C$; Platanus occidentalis, $2.57^{\circ}C$. This standard large wide canopy species was analyzed by the roadside to provide shade to have a significant impact on air temperature reduction. In terms of analysis of the relationship between plantation type of roadside trees and air temperature, the average air temperature difference for 1 row of tree type was $1.80^{\circ}C$; for 2 rows of trees it was $2.15^{\circ}C$. In terms of analysis of the relationship between the roadside green area structure and air temperature, for tree type, average air temperature $1.94^{\circ}C$: for tree+shrub type, average air temperature $2.49^{\circ}C$; for tree+mid-size tree+shrub type, average air temperature $2.57^{\circ}C$. That is, air temperature reduction was more effective in a multi-layer structure than a single layer structure. In the relationship analysis of green volume and air temperature reduction, the air temperature reduction effect was enlarged as there was a large amount of green volume. There was a relationship with the green volume of the road, the size of the tree and number of tree layers and a multi-layer structured form of planting. The canopy volume was large and there were a great number of rows of the tree layer and the plantation type of multi-layer structure, which is what is meant through a relationship with the green volume along the roadside. Green composition standards for air temperature reduction effects and functional improvement were proposed based on the result. For a pedestrian street width of 3m or less in the field being ideal, deciduous broadleaf trees in which the canopy volume is small and the structure of the tree+shrub type through the greatest 1m green bend were proposed. For a pedestrian street width of over 3m, deciduous broadleaf trees in which the canopy volume is large and is multi-layer planted with green bend over 1m, tree+mid-size tree+shrub type was proposed.

• The Korean Journal of Ecology
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• v.19 no.4
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• pp.253-261
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• 1996

This study was conducted to clarify the relationship between bird community and forest structure from early May to mid June, 1988 in two sites which had different forest structures due to silvicultural practice, located in the Tomakomai Experimental Forest of Hokkaido University, Hokkaido, Japan. Quantitative ahbitat analysis was applied to elucidate difference between the two study sites, and territory mapping method and guild analysis were used for assessment of the bird community. Dominant tree species were Quercus mongolica, Magnolia obovata, Prunus sargentii, Acer mono and Tilia japonica. Unithinned site had more foliage coverage in upper and middle layers, but in lower layer had less coverage than thinned site. Thirty four species of birds were recorded and of them only 21 species occupied territories within the study area. Dominant species were Ficedula narcissina, Phylloscopus occipitalis, Parus major, Passer rutilans, Sitta europaea and Parus palustris in the study area. The unmber of breeding species of the two sites were equal, but the species composition of breeding bird communities was different between the sites. The number of species and pairs on hole-nesting guild were greater in the unthinned site, but those on ground-nesting guild were greater in the thinned site. Canopy-nesting guild showed no significant difference between the two sites. Silvicultural practice such as proper thinning appeared to be not inadequate to all of the forest birds, probably good to bush and ground nesting guild, and to tree & bush and ground foraging guild. The silvicultural practice also did not considerably affect the hole and canopy-nesting guild.

• Korean Journal of Environment and Ecology
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• v.21 no.1
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• pp.67-73
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• 2007

To investigate the coastal forest structure and its ecological characteristics in Busan, four typical sites, Taejongdae, Molundae, Amnam Park, and Igidae, were selected and surveyed. These sites are famous coastal areas in Busan. According to the analysis of vegetation structure, Pinus thunbergii was a dominant species at the canopy layer in all sites. But at the understory layer, Eurya japonica in Taejongdae and Molundae, Ficus erecta in Igidae and Eurya japonica and Prunus sargentii in Amnam Park were dominant species.

• Journal of Korean Society of Forest Science
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• v.89 no.4
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• pp.502-512
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• 2000

Old-growth development for two different second-growth northern hardwood stands in the North America was evaluated with a computer simulation. The two sites compared were a representative 77 year old even-aged stand (Phelps) with heavy dominance by pole size classes, and an older uneven-aged stand with some existing old-growth structural features (Wildcat Creek). Each stand was evaluated in its natural progress toward old-growth structural conditions with stand structure, size distribution of live and dead trees, percent stand area in canopy gaps, and visual canopy profile and overhead view. The Phelps stand reached the minimum structural threshold for the old-growth stage after 74 years. Only 13 years was required for Wildcat Creek stand to reach the old-growth threshold. During the 45 years of simulation, the diameter distributions of both stands became broader and flatter. DBH distribution of dead trees had a general descending trend over the simulation in each stand. Gaps at Phelps were typically small after 45 years. Gap area at Wildcat Creek was somewhat more constant over the 45 years of simulation but a big gap was formed because of the death of several adjacent large trees.