• Journal of the Korean Wood Science and Technology
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• v.29 no.2
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• pp.118-125
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• 2001

In this study, it was examined the characteristics of bending property of red pine(Pinus densiflora S, et Z.) related to slope of grain. At first, we have investigated the characteristics of wood species for bending property. At second, it was examined the relationships between grain angle and its related bending property. Specimens were made following to grain angle $0^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $90^{\circ}$, respectively. Dimension of wood materials was $10mm(T){\times}20mm(R){\times}350mm(L)$. Microwave irradiation time for bending process was 30, 60, 90, 120 seconds. The result of this study were as follows ; 1. Grain angle of wood was closely related to Young's modulus on bending process. In the process of bending with various grain angle, wood bending was easily proceed on the high grain angle range. 2. However, the strength of bent wood was very weak when the grain angle was high. Therefore, it was considered suitable grain angle for bending was existed. 3. The characteristics of wood properties for wood bending were very different among wood species.

• The Korean Journal of Quaternary Research
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• v.14 no.2
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• pp.87-99
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• 2000

May-June precipitation (253 years : A.D. 1746∼1998) of Yungdong region (coastal area of East-central Korea) was reconstructed using two tree-ring chronologies of Pinus densiflora sampled from Daeseung Fall area in Sorak Mountains. Dry periods were 1765∼1800 (longest dry period), 1835∼1845, 1890∼1910, 1920∼1940 and 1980∼1995, and wet ones 1810∼1830, 1850∼1890 and 1950∼1970. In long-term variation, late 18th century was dry. The 19th century May-June (250㎜) was wetter than the 20th century (231㎜) and the former indicated higher variability than the latter. Major wet/dry periodicities in May-June precipitation series reconstructed were 3 years in short term and 60∼80 years in long term. The present reconstructed data agreed to the ancient rain gauge 'Chukwooki' data (1777∼1907) of Seoul (central-west Korea) in low frequency variations except early 1800s.

• Journal of the Korean Wood Science and Technology
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• v.10 no.3
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• pp.133-134
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• 1982

This experiment has been made to investigate the absorption of watersoluble zinc chloride by Pinus densiflora S. et Z. at different moisture content, under soaking process, to decide the optimum content condition for the maximum absorption of zinc chloride by the wood tested and to investigate the concentration of zinc chloride affecting each moisture content of wood. Material was cut in the Dept. of Forest, College of Agr. S.N.U. Suwon, Korea. Sample was divided into sap and heartwood group and cut $2{\times}2{\times}2\;cm$ in size, having exact three dimensions, using the part of D.B.H. The numbers of sample were 20 pieces for each moisture content condition for both sap and heartwood. Especially, the samples were protected from exposure to keep moisture content in green condition. The ranges of moisture content tested were as the table 3 and 4. The conclusions were as follows: 1. With 3% zinc chloride solution, the rate of absorption decreased with the time increased, if the air seasoned Korean red pine (Pinus densiflora S. et Z.) was treated in steeping process. Initial absorption for 30 minutes was more than 50% of total absorpon for 24 hours. 2. Rate of absorption was same under the green condition, while rate of absorption under the moisture content 7 to 30% varied. 3. Although it was not quite proportional change in the absorption with the difference of moisture content, the great change in the absorption occured by seasoning. With exception sap green condition, sapwood twice more permeable than the heartwood in the oven dried condition and it has been observed the nearly same amount of absorption at the moisture content of 7%, 10% and 15% respectively in heartwood. 4. It was better from water in wood from view-point of absorption of zinc chloride solution, but it was difficult practically to obtain the smallest moisture content, and then it was decided that values of allowable moisture content, on the basis of mean absorption, were 15% to 20% in the sapwood, and in the heartwood, 10% to 15%. The mean absorption for each moisture content in the sap and the heartwood were as following. 5. In general, the concentration of zinc chloride after steeping was nearly same between moisture content and sap and heartwood respectively.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.4
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• pp.327-335
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• 2014

Current volume tables might underestimate or overestimate the volumes of individual trees in a specific region because the tables were made using the data from broad regions within South Korea. Therefore, to solve this problem, this study was conducted to develop local stem volume tables reflecting the local growth pattern and properties using stem taper equations in the regions of Hongcheon and Yeongju. We developed the local stem volume table for Pinus densiflora, which is the widely planted species in South Korea. To derive the most suitable taper equation for estimating the stem volume of region, three models of Max & Burkhart, Kozak and Parresol et al. were applied and their fitness were statistically analyzed by using the Fitness Index, Bias, and Standard Error of Bias. The result showed that there is a significant difference among the three models, and the Fitness Index of the Kozak model was highest compared to the other models. Therefore, the Kozak model was chosen for generating stem taper equation and stem volume tables for P. densiflora. The result from the developed stem volume tables of each region was compared to the current stem volume tables with driven by the data of tree growth obtained throughout the nation. The result showed that there is a significant difference (0.000< ${\alpha}=0.05$) in two regions, Hongcheon and Yeongju, and also there is a significant difference (0.000< ${\alpha}=0.05$) between the two regions.

• Journal of Forest and Environmental Science
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• v.15 no.1
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• pp.107-116
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• 1999

For the study on the variation of Pinus densiflora S. et Z. natural populations. 13 stands were selected in Kangwondo region in 1994. They were located in Hyoja-Dong, Chunchon-Si [plot 1]; Sinnam-Myun, lnje-Gun [plot 2]; Buk-Myun, lnje-Gun [plot 3]; Seo-Myun, Yangyang-Gun [plot 4 and 5]; Sonyang-Myun, Yangyang-Gun [plot 6]; Toseong-Myun, Goseong-Gun [plot 7]; Synrim-Myun, Wonju-Si [plot 8]; Dunnae-Myun, Hoengsong-Gun [plot 9]; Jinbu-Myun, Pyungchang-Gun [plot 10]; Sogumgang, Kangneung-Si [plot 11]; Seo-Myun, Ulchin-Gun [plot 12]; and Mitan- Myun, Pyungchang-Gun [plot 13]. The morphological characteristics of needles and cones were investigated for twenty individual trees from each population. The results are summarized as follows: 1. Among needle characteristics, length, the number of serration. and the number of stoma row were significantly different among populations and between individuals within a population. They were 69.3~91.9mm, 25.1~28.7 per 0.5cm, and 4.1~6.2 rows for abaxial side and 2.9~4.6 rows for adaxial side, respectively. 2. Among cone characters surveyed. length and diameter were significantly different among populations and between individuals within a population. They were 31.1~43.7mm and 20.0~24.1mm, respectively. 3. A highly positive correlation was observed between the number of stoma row of abaxial side and that of adaxial side. and between length and diameter of cone. But the number of serration was negatively correlated with all traits. 4. The distance from seashore was positively correlated with needle length and the number of serration, but negatively correlated with the number of stoma row and cone length. However, the altitude was positively correlated with the number of serration, but negatively correlated with the number of stoma row and cone length. 5. Cluster analysis using average linkage method for needle and cone characteristics showed two groups to Euclidean distance 1.0. They were group I consisting of plots 1, 8, 12, and 13 and group II of plots 2, 3, 4, 5, 6, 7, 9, 10, and 11. However, group II was divided again to Euclidean distance 0.8, that is a group including plots 2, 3, 9, and 11 and the other group comprising plots 4, 5, 6, 7, and 10.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.4
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• pp.10-16
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• 2013

Korean housing developers are in a very competitive market and their way of attracting buyers is landscaping better than competing firms do. Thus, transplanting larger pine trees(Pinus densiflora S. et. Z.) is in vogue. A typical case is a pine tree about 30-year old, 35 diameters at breast height, transplanted 223 km afar from the Gangwon Province to Seoul. We estimated and compared carbon emissions during the whole transplanting works, and carbon intake by the tree if it survives 50 more years on site. Findings are; first, a large tree will take up and sequestrate approximately 90 kgC if it survives 50 more years. Second, transplanting works emit approximately 113.69 kgC, which is about 1.26 times of its possible future intake of carbon. Landscaping is a legal requirement for the purposes not only of aesthetics but also of environmental quality. Transplanting larger trees that came from a dam or a road building site may be inevitable and acceptable. However, transplanting larger trees long distance was evaluated to be harmful to the environment. It is strongly recommended to prohibit transplanting large trees. Landscape professionals need to guide clients to have desirable consumer attitude.

• Journal of Korean Society of Forest Science
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• v.44 no.1
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• pp.36-42
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• 1979

A study was conducted on the genetic correlations and simple correlations between some characters of the plus trees of Pinus densiflora. The results can be summarized as follows. 1. Simple correlations height growth by age was measured and high correlation(above r=0.9) were observed. Therefore, early selection seems to be possible in the light of the results made up to 8 years old. 2. Genetic correlation between height and root collar diameter was 0.266 and the correlation between height and branch diameter was 0.091 and 0.391 was between root collar diameter and branch diameter.

• Journal of Korean Society of Forest Science
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• v.94 no.3 s.160
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• pp.191-196
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• 2005

This studies were conducted to compare ozone sensitivity among half-sib families of Japanese red pine (Pinus densiflora S. et Z.). 90 families were exposed in walk-in type chambers to charcoal-filtered air and 100 ppb ozone for 8 hours daily, 5 consecutive months. We surveyed the foliar injury, Relative DRC (diameter at root collar) growth and relative dry weight after fumigation. After 5 months of exposure, foliar injury ranged from 1.9% at tolerant group to 15.2% at sensitive group. Relative DRC growth rates showed increased 12% at tolerant group, but reduced 23% at sensitive group. Total dry weight increased 17% at tolerant group, otherwise reduced by 33% at sensitive group, relative to the control. The root biomass showed more sensitive than the other part biomass. On the basis of the results of these screening studies, families Kangwon 04, 16, 26, 27 and 73 were determined to be tolerant; Kangwon 40, 52, 83, Gyeonggi 01 and Gyeongbuk 20 to be sensitive to ozone. Considerable genetic variation in ozone responses occurred, as shown by differences in sensitivities among families and among groups. These results indicate that tolerant groups of P. densiflora exhibited a high degree of resistance to ozone pollution injury.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.82-89
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• 2013

Harvest is one of the major disturbances affecting the soil carbon (C) dynamics in forests. However, researches on the long-term impact of periodic harvest on the soil C dynamics are limited since they requires rigorous control of various factors. Therefore, we adopted a modeling approach to determine the long-term impacts of harvest interval, harvest intensity and post-harvest residue management on soil C dynamics by using the Korean Forest Soil Carbon model (KFSC model). The simulation was conducted on Pinus densiflora S. et Z. stands in central Korea, and twelve harvest scenarios were tested by altering harvest intervals (50, 80, and 100-year interval), intensities (partial-cut harvest: 30% and clear-cut harvest: 100% of stand volume), and the residue managements after harvest (collection: 0% and retention: 100% of aboveground residue). We simulated the soil carbon stock for 400 years for each scenario. As a result, the soil C stocks in depth of 30 cm after 400 years range from 50.3 to 55.8 Mg C $ha^{-1}$, corresponding to 98.1 to 108.9% of the C stock at present. The soil C stock under the scenarios with residue retention was 2.5-11.0% higher than that under scenarios with residue collection. However, there was no significant impact of harvest interval and intensity on the soil C stock. The soil C dynamics depended on the dead organic matter dynamics derived from the amount of dead organic matter and growth pattern after harvest.

• Journal of the Korean Wood Science and Technology
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• v.17 no.4
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• pp.44-56
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• 1989

To recover much residual lignin from the black liquor of kraft pulp. the black liquor was extracted and purified with many organic solvents. Many kinds of lignins were isolated from each fraction obtained and the characteristics of these lignins investigated by $^{13}C$-NMR spectroscopy. If M$\ddot{o}$rck's method was compared with Kirk's method. M$\ddot{o}$rck's method was better than Kirk's method because the particular signals of each lignin occur more in the former than m the latter. Especially the $^{13}C$-NMR spectrum of the MCS fraction identifies with those of other researchers. The experiment that the kraft lignin from Pinus densiflora S. et Z. found in Korea was investigated by $^{13}C$-NMR spectroscopy was performed first in Korea.