• Journal of Practical Agriculture & Fisheries Research
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• v.14 no.1
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• pp.47-59
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• 2012

The effects of organic calcium compounds (ACa) tree-spray for late growing stage on the mineral nutrition concentration of fruit, russet and quality in 'Fuji' apple were investigated. Optimum spray concentration of leaves by ACa tree-spray during late growth stage were ranged 125 times among 1,000 times. Also, Optimum concentration of fruits was effected to 125 times. Optimum spray times of leaves effected by ACa 500 times tree-spray during late growth stage were effective in one times (Sept. 25) and three times (Sept. 25, Oct. 5, 15). Also, Optimum times concentration of fruit skin was effected to one times (Sept. 25) and fruit flesh was effected two times (Sept. 25, Oct. 5) and three times (Sept. 25, Oct. 5, 15). Phytotoxicity by tree-spray of ACa concentration and times different not occur to leaf and fruit.

• Journal of Korean Society of Forest Science
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• v.104 no.1
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• pp.104-110
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• 2015

The objective of this study was to develop allometric equations for the estimation of crown fuel biomass of Pinus koraiensis in Korea. A total of twenty four representative sample trees were destructively sampled in Gapyeong, Hongcheon, and Jeongseon. Crown fuels were weighed separately for each fuel category by size class and by living and dead. The results of this study showed that the needles contributed the largest biomass (16.6 kg, 34.7%), followed by live branches with size ranging from 2~4 cm (9.0 kg, 18.9%), 1~2 cm (6.6 kg, 13.8%), <0.5 cm (5.1 kg, 10.6%), 0.5~1 cm (4.9 kg, 10.3%), and dead branches (3.2 kg, 6.8%), while the live branches with 4 cm (2.4 kg, 4.9%) as the lowest. The adjusted coefficient of determination values were the highest ($R^2_{adj}=0.6021{\sim}9742$) and standard error of estimate were the lowest (S.E.E.=0.2018~0.7271) in allometric equation $lnWt={\beta}_0+{\beta}_1lnD$. The available fuels that are consumed during crown fires (i.e., needles and twigs with diameter less than 1 cm) comprised 55.6% of the total crown fuel biomass.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.359-366
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• 2011

The objective of this study was to analyze the changes of crown fire hazard possibility from the effects of forest tending works (FTW) in Pinus densiflora stands in Korea. The study sites were located in Youngju (FTW) and Bonghwa (Control) areas. Ten representative sample trees were destructively felled at each areas to analyze the crown fuel characteristics. The results of this study showed that crown fuel moisture content in Youngju and Bonghwa areas were 103.6% and 104.4%, respectively. The needles and twigs with less than 1cm diameter accounted 50.3% of the total crown fuel load in Youngju area and 62.0% in Bonghwa area. On the other hand, it was observed in Youngju that the canopy bulk density was $0.11kg/m^3$ lower but have 1.3 m higher average canopy base height therefore having a possibility of lower crown fire hazard as compared to Bonghwa that had higher canopy bulk density and lower canopy base height.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.8-13
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• 2011

This study was carried out to investigate the change of photosynthesis, leaf and fruit according to crown layers in Actinidia arguta and hybrid kiwi. Photosynthesis rate (PPFD $1,000{\mu}mol{\cdot}m^{-2}s^{-1}$) were 5.82, 7.11, $9.54{\mu}mol\;CO_2\;m^{-2}s^{-1}$ at lower, middle, and upper position, respectively in 3 layer cultivation type. The length and area of leaves collected from lower position have lager value than upper position. The fruit quality of A. arguta and hybrid kiwifruit increased with increasing crown height. A linear correlation ($R^2=0.72$, 0.89 and 0.98) was shown between fruit weight (Boeun 4, Injea 16 and HM3) and the height of crown layer(layer 1, 2, and 3). From the results, we can suppose that the tree of the upper position of crown layer in the cultivation of A. arguta and hybrid kiwifruit produce high quality fruit due to its high photosynthesis ability.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.793-799
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• 2016

This study examined Platanus orientalis and Ulmus davidiana planted in downtown parks to identify the correlations among microclimatic factors such as temperature in the crown, air flow, and wind speed. For the field survey, measurements were taken at 1 hour intervals from 09:00 am to 06:00 pm in August. For the measurement of microclimatic factors, data on temperature, light intensity, air flow, and wind speed were collected using a quantum sensor (PAR Quantum Sensor SKP215), a precision thermometer (Pt1000-Sensor), and a combination anemometer (1467 G4 & HG4). The results of the analysis demonstrated that both Platanus orientalis and Ulmus davidiana, showed a greater cooling effect inside the crown as compared with the outside temperature. The cooling effect inside the crown was more evident with air flow and wind speed factors. With relation to wind, the inner temperature of the crown of Platanus orientalis decreased due to air flow while that of Ulmus davidiana decreased due to wind speed. With no wind, the average variation in temperature inside the crown was $-0.9^{\circ}C$ for Ulmus davidiana and $-0.958^{\circ}C$ for Platanus orientalis, indicating that Platanus orientalis was relatively more effective in lowering the temperature of the planting space than Ulmus davidiana. This study is significant because it shows that different tree species have different effects on the microclimate and that factors affecting the formation of the microclimate of trees may vary with species. Further studies on species other than broad leaf trees, such as evergreen trees and shrubs, are required in order to plan the distribution of landscaping trees that are effective in regulating the microclimate within urban green spaces.

• Korean Journal of Remote Sensing
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• v.35 no.6_2
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• pp.1083-1093
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• 2019

The purpose of this study is to detect the burned area change by direct burning of tree canopies and post-fire mortality of trees via analyzing satellite imageries from the Korea multi-purpose satellite-2 and -3 (KOMPSAT-2 and -3) for two large-fires over the Goseong-Sokcho and Gangneung-Donghae regions in April 2019. For each case, the burned area was compared between two dates: the day when the fire occurred and 15-18 days after it. As the results, within these two dates, there was no substantial difference in burned area of sites whose severities were marked as "Extreme", but sites with "High" and "Low" severities showed significant differences in burned area between the two dates. These differences were resulted from the lagged post-fire browning of canopies which was detected by images from in-situ observation,satellite, and the unmanned aerial vehicle. The post-fire browning started after 3-4 days and became apparent after 10-15 days. This study offers information about the timing to quantify the burned area by large fire and about the mechanism of post-fire mortality. Also, the findings can support policy makers in planning the restoration of the damaged areas.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.1
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• pp.46-54
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• 2021

This study compared and analyzed the effects of forest tending works on the vertical distribution of wildfire fuel loads on Pinus densiflora stands in Gyeongbuk province. The study sites were located in Youngju and Bonghwa in Pinus densiflora stands. A total of 10 sample trees were collected for the development of the crown fuel vertical distribution model. The 6th NFI (National Forest Inventory) selected a sample point that only extracted from managed and unmanaged stands of Pinus densiflora in the Gyeongbuk province. The fitness index (F.I.) of the two models developed was 0.984 to 0.989, with the estimated parameter showing statistical significance (P<0.05). A s a results, the vertical distribution of wildfire fuel loads range of unmanaged stands was from 1m to 11m with the largest distribution at point 5m at the tree height. On the other hand, the vertical distribution of wildfire fuel loads range of the managed stands was from 1m to 15m with the largest distribution at the point of 8m at the tree height. The canopy bulk density was 0.16kg/㎥ for the managed stands and 0.25kg/㎥ for the unmanaged stands, unmanaged stands were about 1.6 times more than managed stands. This result is expected to be available for simulation through the implementation of the 3D model as crown fuel was analyzed in three dimensions.

• The Journal of Natural Sciences
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• v.6 no.1
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• pp.49-54
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• 1993

This study was conducted to investigate the influence of various calcium salts on the accumulation of calcium in apple fruits when sprayed on whole tree. Differences in the total calcium contents of fruits were found between calcium sources and cultivars. In 'Tsugaru' , calcium nitrate, calcium chloride, and calcium carbonate were all effective but only calcium chloride and calcium carbonate appeared to be effective in 'Fuji' . Major parts of the applied calcium were accumulated in the feel and outer flesh. Ethylene evolution of fruit was retarded during storage with the increase of total calcium content in 'Fuji' fruit treated calcium acetate.

• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.36-38
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• 1977

Some characteristics of rainfall interception and surface runoff from total rainfall at a forest stand mixed with Pinus densiflora and Alnus hirsuta in 1975 was analysised and the results obtained are as fellow; 1. The annual interception of rainfall by the forest canopy was 19.3 percent to annual rainfall 1,072.7mm. 2. The rate of rainfall interception in the dry season as spring and early summer was of 20 to 50 percent and less than 15 percent in the rainy season as summer. 3. About 50 percent of rainfall was intercepted in case of less than 10mm of every rainfall by the forest canopy and, in more than 20mm, about 20 percent intercepted.

• Korean Journal of Environment and Ecology
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• v.13 no.1
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• pp.34-48
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• 1999

본 연구는 주요 조경수목에 대한 생장예측모델을 추정하여 적정 식재간격을 산정하기 위해 실시하였다. 조경식재에서 많이 사용되는 9개 수종을 대상으로 수종별 30주 이상씩의 개체를 선정한 후, 상관성이 높은 측정변수 간에 회귀분석을 실시하여 생장예측모델을 추정하였다. 그리고 서울 시내 2개 아파트단지 녹지를 사례연구지로 선정하여 생육상태를 파악하고 모델과 비교하였다. 전체적으로 교목층 위주의 식재로 인해 식재밀도가 과밀하여 수관이 왜곡되고 기형적으로 생장하는 현상이 발생하고 있는 바, 수관중복률과 수관왜곡률을 분석한 결과에 의하면 현재의 식재간격이 매우 조밀한 것으로 밝혀졌다. 결론적으로 시간경과에 따른 주요 조경수종의 규격별 생장예측을 통해 목표년도별 적정 식재간격을 제안하였는데, 목표년도를 식재 후 5년으로 본다면 상록교목은 2.0m, 낙엽교목은 3.0~4.0m, 낙엽아교목은 2.0~2.5m의 식재간격이 적당하고, 식재 후 10년을 목표년도로 한다면 상록교목의 경우 3.0m, 낙엽교목은 4.0~6.0m, 낙엽교목은 2.5~3.0m의 간격을 유지하여야 한다. 한편, 본 연구의 결과와 서울시 조례기준 식재밀도를 비교하였는데, 식재후 5년이 경과한 시점에서는 0.23본/m2, 10년 경과시점에서는 0.12본/m2이 적정 식재밀도로 밝혀져 현재 0.2본/m2으로 정하고 있는 서울시 교목식재 관련 기준은 5년 정도를 목표시점으로 한다면 적절한 수준임을 알 수 있었다. 그러나 식재 후 10년이 경과하면 수관중복률이 25%를 초과하게 되므로 쾌적한 녹지환경을 유지하기 위해 반드시 적절한 관리를 실시해야 할 것으로 판단되었다.