• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.463-467
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• 2004

This study was carried out to estimate of leaf area index (LAI) rapidly using plant canopy analyzer, comparing with specific leaf area (SLA) and leaf area ratio (LAR) in rice from 2001 to 2002 at Honam Agricultural Research Institute in Iksan Korea. The relationship between LAI values taken by plant canopy analyzer and by leaf area meter showed high correlation at each growth stages of rice. LAIs obtained by plant canopy analyzer were highly correlated with that by leaf area meter which were the highest in Dongjinbyeo and the lowest in Hapcheon1. Specific leaf area (SLA) of all rice cultivars were tend to decrease remarkably with the progress of growth stage. It was found that the SLA of Dasanbyeo was the highest and that of Hapcheon1 was the lowest among rice cultivars tested. Leaf area ratios (LARs) was also decreased with the progress of growth stage.

• The Korean Journal of Ecology
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• v.8 no.2
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• pp.61-68
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• 1985

The modeling of interception and absorption of light was studied in plant canopies at Mt. Kwanak. Followering results were obtained. Light intensity passing through the stacked leaves is attenuated exponentially. This phenomenon seems to be more clearly applied to the plant canopies, if they have large cumulative leaf area and are matured densely. Light interception and absorption are influenced by leaf thickness, shape pigments, and leaf area, and they have great effect on the maturation of canopies. It was confirmed that the light penetrating through the stratified canopies is decreased exponentially in dual pattern. The cumulative leaf area of a definite space in a certain plant canopy is the same as the growth of leaf area of the canopy at that time. A hypothetical model for calculating the light absorption in plant canopies, was established on the bases of phenomena that incident light is captured at the maximum level and light inerception effect is minimized by leaves.

• Korean Journal of Remote Sensing
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• v.35 no.4
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• pp.545-560
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• 2019

Unlike other critical forest diseases, pine pitch canker in Korea has shown rather mild symptoms of partial loss of crown foliage and leaf discoloration. This study used high-resolution satellite images to detect and monitor canopy decline by pine pitch canker. To enhance the subtle change of canopy reflectance in pitch canker damaged tree crowns, multi-temporal analysis was applied to two KOMPSAT multispectral images obtained in 2011 and 2015. To assure the spectral consistency between the two images, radiometric corrections of atmospheric and shadow effects were applied prior to multi-temporal analysis. The normalized difference vegetation index (NDVI) of each image and the NDVI difference (${\Delta}NDVI=NDVI_{2015}-NDVI_{2011}$) between two images were derived. All negative ΔNDVI values were initially considered any pine stands, including both pitch canker damaged trees and other trees, that showed the decrease of crown foliage from 2011 to 2015. Next, $NDVI_{2015}$ was used to exclude the canopy decline unrelated to the pitch canker damage. Field survey data were used to find the spectral characteristics of the damaged canopy and to evaluate the detection accuracy from further analysis.Although the detection accuracy as assessed by limited number of field survey on 21 sites was 71%, there were also many false alarms that were spectrally very similar to the damaged canopy. The false alarms were mostly found at the mixed stands of pine and young deciduous trees, which might invade these sites after the pine canopy had already opened by any crown damages. Using both ${\Delta}NDVI$ and $NDVI_{2015}$ could be an effective way to narrow down the potential area of the pitch canker damage in Korea.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.1
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• pp.13-19
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• 2020

This study compared RGB color images with canopy light interception (LI) and leaf area index (LAI) measurements for low cost and low labor. LAI and LI were measured from vertical gap fraction derived from top of digital image in soybean canopy cover (cv Daewonkong, Deapongkong and Pungsannamulkong). RGB color images, LAI, and LI were collected from V4.5 stage to R5stage. Image segmentation was based on excess green minus excess red index (ExG-ExR). There was a linear relationship between LAI measured with LI (r²=0.84). There was alinear relation ship between LI measured with canopy cover on image (CCI) (r²=0.94). There was a significant positive relationship(r²=0.74) between LAI and CCI at all grow ingseason. Therefore, it is expected that in the future, the RGB color image could be able to easily measure the LAI and the LI at low cost and low labor.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.2
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• pp.137-143
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• 2008

Rapid canopy closure (RCC) is one of the physiological attributes that may enhance genetic yield potential of rice (Oryza sativa L.) in a growing season. Crop growth before canopy closure could be described by an exponential equation of $y\;=\;{\alpha}{\cdot}{\exp}({\beta}{\cdot}t)$ where $\alpha$ is the crop leaf area index (LAI) or shoot dry weight (DW), t is the thermal time, $\beta$ is the LAI or DW at the beginning of the exponential growth and is the relative growth rate of LAI ($m^2m^{-2}^{\circ}C^{-1}$) or DW($gg^{-2}^{\circ}C^{-1}$). Field experiment using 22 cultivars revealed that the exponential growth phase before canopy closure can be divided into two sections; an earlier section during which crop dry weight and LAI of varieties are highly dependent on $\alpha$ and a second section where crop dry weight and LAI are highly dependent on $\beta$. Grain weight had significantly positive correlation with $\alpha$ parameter and dry weight and LAI during early exponential phase. The parameter $\beta$ of the exponential growth curve had positive and significant correlation with the LAI and dry weight during the late exponential growth phase, grain number per unit area, and grain yield. There was genotypic difference for RCC parameters, $\alpha$ and $\beta$, indicating the possibility of genetic improvement for these traits.

• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.452-460
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• 2000

This study was to investigate the growth characteristics, physiological adaptation of Pinus densiflora(Japanese Red Pine) seedlings at the artificial canopy gap in the Quercus acutissima plantation and to analyze its natural regeneration mechanism. Photosynthetic and transpiration rates were analyzed by different levels of photosynthetically active radiation and by seedling growth. Comparing to seedlings at the open area, those at the canopy gap showed more growth in height than in diameter with different levels of light quality and low light intensity, and the increase rate of dry weight was higher in the aboveground than in the underground, maintaining relatively high T/R rate. The C/F(the ratio of non-photosynthetic organs to photosynthetic organs in dry weight) of the aboveground at the canopy gap was higher than that at the open area by 0.1~0.2, while light saturation and light compensation points at the canopy gap were lower than that at the open area by $300{\mu}mol\;m^{-2}s^{-1}$ and 40%, respectively. The seedlings appeared to have shade tolerance to a certain extent at the young growth stage despite Pinus densiflora is typically classified shade-intolerant species. With light intensity lower than $400{\sim}450{\mu}mol\;m^{-2}s^{-1}$, photosynthetic rate and water use efficiency relatively increased by effective use of light energy.

• Journal of Environmental Science International
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• v.16 no.8
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• pp.881-889
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• 2007

The flora of vascular plants in Jangsanbong located at Busan Metropolitan City was investigated from April 2003 to April 2004. Vascular plants in the surveyed area were 254 taxa that belonged to 78 families, 175 genera, 218 species, 34 varieties, and 2 forma. Among them, 20 taxa of evergreen broad trees, 31 taxa of naturalized plants were identified, and especially Rubus trifidus was first recorded in Busan. In the upper part of a circular road dominant species was Pinus thunbergii. In the lower part of a circular road and the coastal area, dominant species were Platycarya strobilacea, Clerodendron trichotomum, Euscaphis japonica, Quercus aliena, Quercus dentata, Mallotus japonicus, which distribute mainly in the subtropical and temperate zone. In the surveyed area, the canopy consistsed of tall trees, Pinus thunbergii, and the understratum were trees such as Eurya japonica, Ficus erecta, Ligustrum japonicum, Prunus sargentii, and Celtis sinensis var. japonica.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.454-462
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• 2014

This study was carried out to determine the effect of tree height on light transmission, spray penetration, tree growth performance, fruit quality attributes, and labor productivity in the slender-spindle system of 'Hongro'/M.9 apple trees. With increasing tree height, the light penetration into the internal parts of the canopy decreased, especially in the lower canopy. Leaf area index (LAI) increased with increasing tree height, thereby leading to a reduction in the extent of spray penetration into the interior of the canopy. With increasing tree height, shoot growth was more vigorous but produced slender shoots in the upper canopy compared to the lower canopy. Although the soluble solid content and coloration of fruit decreased, there was no difference in fruit firmness and acidity. In addition, the number of final fruit set increased, although the production of large fruit (> 305 g) decreased. The increase in tree height also significantly increased the labor required for practices such as thinning of flowers and fruits, pruning, and harvesting. Nevertheless, this problem of increased in labor input in taller trees would was eased by use of a mechanical lift. Utilizing a lift for thinning the flowers of trees 4.5 m in height saved 14.6 min per tree, compared to the use of ladder. Therefore, it is highly considerable that in order to enhance light transmission and fruit coloration, light conditions should be improved in the internal tree canopy of slender-spindle systems.

• Korean Journal of Environmental Agriculture
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• v.8 no.1
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• pp.30-36
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• 1989

To determine irrigated water temperature under the rice plant canopy, micrometeorological elements air temperature, relative humidity, water temperature, solar radiation, and the rice leaf area index the rice plant canopywere measured. Water temperature under the canopy was also estimated from these data. The results are as follows ; 1. Maximum and minimum temperatures of water in the paddy field were higher about $1-2^{\circ}C$ than those of air temperature. 2. Mean water temperature under the canopy became lower than mean air temperature when the leaf area indices were greater than 4, because of decreased light penetration rates 3. Penetration amounts of net radiation under the canopy can be estimated by an exponential equation 4. Estimated water temperatures under the canopy by a combination method model was adaptable in Suweon, a plain area, but its accuracy was lower in Jinbu, an alpine area.

• 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.