• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.227-234
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• 2007

The forest canopy gap has been well known as a substantial process of forest cyclic regeneration and important role in stand structure, dynamics, and biodiversity of the forest ecosystem. Based on 3,600 $5m{\times}5m$ square grids in a 9ha permanent experimental plot, the study was conducted to evaluate the regeneration pattern of woody species by developmental stage {seedlings (<1 m of height), saplingI (>1 m of height, <2 cm of DBH), and saplingII (2 cm$<200m^2$), $201-400m^2$, $400-600m^2$, $601-800m^2$, and $>800m^2$) in the mixed broadleaved-Korean pine forest. The results indicated that the regenerating trees of Populus ussuriensis occurred only in the canopy gap area, considered to be a typical gap-dependent species. The regeneration of Ulmus japonica, Ulmus laciniata, and Maackia amurensis could be generally satisfied with the gap size of $201-600m^2$, Betula costata and Prunus padus with gap size of $401-800m^2$, Picea koraiensis with gap size of $201-800m^2$, Fraxinus mandshurica and Syringa reticulata var. mandshurica with smaller than $800m^2$, respectively. Acer ukurunduense and Acer tegmentosum were likely to have no problem with the gap size to make gap regeneration. Acer mono and Tilia amurensis looked more capable of regenerating in the closed canopy disregarding the upper crown condition. The regeneration of Pinus koraiensis and Abies nephrolepis had no trouble under the canopy condition in less than $800m^2$of gap size. The density of regenerating shrubs was rather high, especially under the closed canopy, considered to be associated with great amount of regeneration production in such shade tolerant species as Lonicera maackii, Corylus mandshurica, Euonymus pauciflorus, and Philadelphus schrenkii under the closed canopy. Pearson correlation coefficient was computed to compare the similarity among non-gap area and five gap size classes by developmental stages for trees and shrubs. The similarity coefficients among closed canopy and the gap size classes were mostly significantly correlated to each other with a few exceptions.

• Korean Journal of Soil Science and Fertilizer
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• v.5 no.1
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• pp.9-15
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• 1972

Comparative analyses of canopy structure were conducted using newly bred high yield rice cultivars (IR 667-Suwon 213 and 214) and commercial varieties (Jinhung and Paldal) under the field condition. "Canopy score" as criteria of canopy structure was proposed. The results were summerized as follows: 1. IR667 line (IR8${\times}$Taichung Native 1${\times}$Yukara) showed lower canopy height, greater tiller openness, smaller leaf openness and leaf length ratio (flag leaf/3rd), shorter 4th and 5th internode length, greater diameter of 5th internode, consequently greater leaf area index, panicle weight and leaf weight ratio (leaf/leaf sheathculm) as merits, and greater leaf width, smaller leaf number(number of leaf/$m^2$)and specific leaf area($cm^2/g$) and faster destruction of canopy by senescence as demerits comparing with commercial varieties. 2. IR 667 line showed much higher "Canopy score", subsequently higher yield. 3. The quality of individual leaf was better in the commercial varieties indicating that the best combination for the better yield would be the leaf of commercial varieties with the structure of IR667 line.

• Journal of Biosystems Engineering
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• v.36 no.1
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• pp.15-22
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• 2011

An experimental variable rate nursery sprayer was developed to adjust application rates for canopy volume in real time. The sprayer consisted of two vertical booms integrated with ultrasonic sensors, and variable rate nozzles coupled with pulse width modulation (PMW) based solenoid valves. A custom-designed microcontroller instructed the sensors to detect canopy size and occurrence and then controlled nozzles to achieve variable application rates. A spray delivery system, which consisted of diaphragm pump, pressure regulator and 4-cycle gasoline engine, offered the spray discharge function. Spray delay time, time adjustment in spray trigger for the leading distance of the sensor, was measured with a high-speed camera, and it was from 50 to 140 ms earlier than the desired time (398 ms) at 3.2 km/h under indoor conditions. Consequently, the sprayer triggered 4.5 to 12.5 cm prior to detected targets. Duty cycles of the sprayer were from 20 to 34 ms for senor-to-canopy (STC) distance from 0.30 to 0.76 m. Outdoor test confirmed that the nozzles were triggered from 290 to 380 ms after detecting tree canopy at 3.2 km/h. The spray rate of the new sprayer was 58.4 to 85.2% of the constant application rate (935 L/ha). Spray coverage was collected at four areas of evergreen canopy by water sensitive papers (WSP), and ranged from 1.9 to 41.1% and 1.8 to 34.7% for variable and constant rate applications, respectively. One WSP area had significant (P < 0.05) difference in mean spray coverage between two application conditions.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.2
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• pp.80-94
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• 2010

The purpose of this study is suggest to restoration model of Pinus thunbergii in Saha-gu, Busan. The result of this study is summarized as follows. As the results of this study, vegetation restoration model is presented by separating community planting and edge planting. In community planting, as a group of canopy, there are 6 species; Pinus thunbergii, Quercus acutissima, Quercus dentata, Quercus serrata, Quercus alienna, Quercus variabilis. As a group of understory, there are 5 species; Platycarya strobilacea, Prunus sargentii, Styrax japonica, Eurya japonica, Morus bombycis. Also as a group of shrub, there were 15 kinds of species; Ulmus pavifolia, Ulmus davidiana, Lindera obtusiloba, Elaeagnus macrophylla, Mallotus japonicus, Ligustrum obtusifolium, Sorbus alnifolia, Rhus trichocarpa, Zanthoxylum schinifolium, Rosa wichuraiana, Rhus chinensis, Viburnum erosum, Rhododendron mucronulatum, Rhododendron yedoense, Indigofera pseudotinctoria. And as a group of edge vegetation, there were 10 kinds of species; Japanese Angelica, Symplocos chinensis, Pittosporum tobira, Lespedeza maximowiczii, Lespedeza bicolor, Rubus coreanus, Rubus idaeus, Vitis thunbergii, Ampelopsis brevipedunculata, Rosa multiflora. Vegetation restoration models of Pinus thunbergii community were calculated the units $400m^2$ for the average populations of the woody layer is 24 in canopy layer, 35 in understory layer, 410 in shrub layer, 34% herbaceous layer ground cover. And the average of breast-high area and canopy area is $10,852cm^2$ in canopy layer, in understory layer $1,546cm^2$, in shrub layer $1,158,660cm^2$. The shortest distance between trees is calculated as 2.0m in canopy layer, 1.9m in understory layer.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.1
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• pp.44-51
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• 2009

In order to determine air temperature difference by canopy layer in the forest, air temperatures were observed at Seolleung Park, Gahngnam-ku, Seoul. from November 9, 2007 to November 8, 2008 by 10 minute interval. The data were analyzed in terms of diurnal variation based on annual and monthly temperature difference. Using calm, less cloudy and no rainy weather data, average air temperature difference between forest and grass was observed as $0.8^{\circ}C$. The maximum air temperature difference was observed at 22:10, 23:20, 23:30 and 23:40 by $2.13^{\circ}C$ and the minimum one observed at 13:00 by $-0.84^{\circ}C$ in diurnal variation. The maximum temperature difference occurred at 19 : 50 on September by $3.67^{\circ}C$, Overall the air temperature in the forest was higher than that of grass at night and lower in midday.

• Journal of Ecology and Environment
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• v.30 no.4
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• pp.325-330
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• 2007

Recognizing the ecological importance of forest gap formation for forest community structure, we examined the differences in species diversity between forest gaps and closed canopy areas for trees and shrubs in three developmental stages (seedling, sapling I, and sapling II) in a typical mixed broadleaved-Korean pine forest. We randomly placed 100 sample plots ($2{\times}2m$ for seedling and sapling I, and $5{\times}5m$ for sapling II) in forest gap and closed canopy areas of a 9 ha permanent sample plot for vegetation surveys of plants of each developmental stage in each habitat type. Even though the formation of forest gaps encouraged the occurrence of gap-dependent species and increased overall species diversity, there were no significant differences in species richness among the three developmental stages for both tree and shrub species (p>0.05). Comparing the two types of sites, statistical tests revealed no difference in species richness for trees, but highly significant differences (p<0.01) between forest types for shrubs for seedlings and sapling I, but not sapling II. Analysis of variance test indicated that there were no significant differences in species diversity among the three developmental stages of tree species (p>0.05) for both Simpson and Shannon indices. The variance for shrub seedlings was significantly different between forest gaps and closed canopy areas, but not for sapling I and sapling II. The analysis showed that the species diversity in forest gaps was significantly different from that of closed canopy areas for seedling and sapling I (p<0.01), but not for sapling II (p>0.05).

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.1
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• pp.52-59
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• 1999

Vegetation canopy plays an important role in $CO_2$/$H_2$O exchange between the biosphere and the atmosphere by controlling leaf stomata. In this study, rice (Oryza sativa L.), a staple crop in Asia was investigated to formulate its single leaf model of photosynthesis and stomatal conductance. Photosynthesis and stomatal conductance were measured with a portable infrared gas analyzer system. Other plant and meteorological variables were also measured. To evaluate empirical constants in this biochemical leaf model, nonlinear least squares technique was used. The maximum catalytic activity of enzyme and the maximum rate of electron transport were $ 100\mu$㏖ $m^{-2}$ $s^{-1}$ and $140 \mu$㏖ m$^{-2}$ s$^{-1}$ (@ 35$^{\circ}C$), respectively. The empirical constants, m and b, associated with stomatal conductance model were 9.7 and $0.06 m^{-2}$ $s^{-1}$ , respectively. On a leaf scale, agreements between the modeled and the measured values of photosynthesis and stomatal conductance were on average within 20%, and the simulation of diurnal variation was also satisfactory On a canopy scale, the Simple Biosphere model(SiB2) was tested using the derived parameters. The modeled energy fluxes were compared against the micrometeorologically measured fluxes over a rice canopy. Agreements between the modeled and the measured values of net radiation, sensible heat and latent heat fluxes, and $CO_2$ flux (i.e., net canopy photosynthesis) were on average within 25%.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.1
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• pp.19-29
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• 2004

This study was carried out to understand the bird community and habitat using condition in the Gildong natural ecological park, from April 2001 to March 2002. In this study, 63 species and 2,075 individuals were observed respectively. The dominant species were Paradoxornis webbianus(33.6%), Emberiza elegans 18.5%), Parus major(6.4%), Pica pica(6.0%), and the diversity of the species was 2.511. With migration, the highest number and percentage to the lowest was residents, summer visitors, winter visitors and passage migrants. Among 17 species which bred in the Gildong natural ecological park, hole(H) was 47.1%, canopy(C) was 41.1% and bush(B) was 11.8% in their nesting guilds. In foraging guilds in breeding season was canopy(c) was 45.7%, water(w) was 23.9% and bush(c) was 15.2%, and, in non-breeding season, canopy was 43.5%, water 23.9% and bush 21.7%. For the habitats of the birds in the Gildong natural cological park, reservoir area was used by herons, ducks and sandpiper, wetland area was used by Lanius bucephalus, Paradoxornis webbianus and buntings, grassland area was used by Paradoxornis webbianus and buntings, and forest area was used by Streptopelia orientalis, woodpeckers and tits. The number of species and individuals of birds observed in the Gildong natural ecological park was higher than other urban parks. We suggest that this was attributed to different habitats such as reservoir, wetland, grassland and forest area constructed in the Gildong natural ecological park.

• Journal of Photoscience
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• v.9 no.2
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• pp.166-169
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• 2002

This paper is a part of the research into effects of increased UV-B (Ultraviolet-B, 280-320nm) upon the ecosystem of field wheat. Based on a 3-year project with intensified UV-B influencing the crop, observation and calculation were made of such factors and parameters as the morphology of a single wheat plant including its leaf area, leaf base angle and proportion of spacing between joints. The results show that the enhanced UV-B signifantly decreased wheat's SSLA, and the increased percentage of the lower LAI is associated with the change in leaf base angle and proportion of spacing between joints.

• Animal cells and systems
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• v.9 no.1
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• pp.41-46
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• 2005

This study was conducted to reveal tree species preference and inter-specific difference of foraging behavior among four canopy-dwelling birds at forest dominated by Quercus mongolica, Acer pseudosieboldian and Carpinus cordata at 1,000 meters above sea level during breeding season of birds from 1995 to 1997 in Mt. Jumbongsan. Breeding birds were about 25 species and dominant birds were Erithacus cyane, Parus ater and Parus palustris. A relatively high number of bush-nesters can be a characteristic of breeding bird community at study area. Three gleaners (Tits, P. varius, P. palustris and P. ater) selectively preferred the trees irrespective of dominant tree species, whereas bark foragers (Nuthatch, Sitta europaea) utilized the dominant trees. The four birds showed significant inter-specific difference in use of foraging location, but the three tits did not show significant inter-specific difference in use of foraging maneuver and trees. Closely related tits may coexist with each other by inter-specific different use of foraging location determined by foliage structure and leaf arrangement.