• Journal of Forest and Environmental Science
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• v.32 no.2
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• pp.113-119
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• 2016

The long lived iteroparous conifers produce male and female gametophyte for hundreds of years once they reach the reproductive stage, however, the production of seed is not frequent. This phenomenon of infrequent seed production in conifers is yet to be understood. An attempt to study this change in cone production in Cedrus deodara of Western Himalayas -a species reported to be mainly monoecious and rarely dioecious has been made. The observations recorded on selected trees of flowering/fruiting stage for four years at four different locations have shown the species to be dioecious with higher percentage of female trees during good seed year but with no definite or predictable pattern of reproduction in the trees. A decline in production of female trees was witnessed at all but one location immediately year after reaching the maximum (good seed year). The phenomenon of seed production has been observed to be cyclic and site specific. A change in the sexual behavior of the trees from male to female or vice-versa, male or female turning monoecious or vegetative and vegetative coming to reproductive was unpredictable.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.6
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• pp.1-15
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• 2011

We recently witnessed increasingly more natural disturbances on forested land. On the other hand, only limited number of nursery grown tree species are available for restoration projects. At the same time, so little on the disturbance resistance of species has been studied that a selection of right species for right site condition becomes very difficult. This study is a compilation of the site specificities and disturbance resistance of each species native to South Korea. Each species was surveyed for 11 items related to site specificities, and 12 items related to disturbance resistance including the resistance to snow damage. This study was conducted for 161 tree species from 44 families : 21 evergreen conifer species, 2 deciduous conifer species, 18 evergreen broad-leaved species, 118 deciduous broad-leaved species, and 2 monocotyledon species. This study suggests that native species in South Korea show resistance to all types of natural disturbances except drought.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.2
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• pp.81-86
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• 2003

The spatial variability of soil heat fluxes in a conifer forest was investigated by meteorological measurement. The maximum daily averages of R $s_{dn}$ and Rn were about 260 W $m^{-2}$ and 180 W $m^{-2}$ . The daily average of G was typically 10% of net radiation during mid-July to mid-August. The measured soil heat flux of $G_{6}$ was suitable to calculate G within 2% error during the study period. A time delay in the maximum nux at a depth of 0.1 m by heat storage was observed. About 10 to 15 W $m^{-2}$ of error can occur, if it is neglected.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.153-156
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• 2008

Comparative analysis of forest fire danger rating on the forest characteristics of thinning area and non-thinning area on forest fire burnt area was studied in this work. To investigate the effect of thinning slash in forest fire, Gangneung-si Wangsan-myeon, Ulgin-gun Wonnam-Myeon, Samchok-si Gagok-Myeon, in which forest fire broke out, were selected. As a result that investigated forest fire danger ratio between thinning slash and non-thinning slash, leeward scorching ratio(36%), crown damage ratio(29%), mortality of branch at the former are higher than those at the latter, leeward scorching ratio of tree, where thinning slash is around, is 10%-20% higher than that of independent tree. So I estimate that thinning slash has a some effect on the intensity of forest fire. And the result to investigate damage of forest fire according to tree species shows that leeward scorching ratio of conifer is 5% higher than that of non-conifer, and mortality of branch of the former is 19% higher than that of the latter. It is considered that forest fire may affect directly to a tree trunk if it diffuse to piled thinning tree because there was no space between thinning trees and trees. Furthermore, it was found that re-ignition had a chance to occur due to lots of piled thinning trees.

• Korean Journal of Environment and Ecology
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• v.34 no.1
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• pp.42-54
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• 2020

This study aimed to analyze the rate of increase and spread patterns of dead trees of the conifer (Abies koreana and others) in subalpine zones by using the high-resolution aerial images in Jirisan National Park around 10 years ago. Furthermore, factors affecting the death of conifer were identified by analyzing the altitude, topographical information, solar radiation, and moisture environment of the site where the dead trees are located. The number of dead trees per unit area increased by two to five times in the Banyabong peak, Yeongsinbong peak, and Cheonwangbong peak in Jirisan National Park over the past decade. The increase was about 2 times in the Banyabong peak, about 3.9 times in the Yeongsinbong peak, and about 5.2 times in the Cheonwangbong peak, indicating the most notable increase in the Cheonwangbong peak. It is estimated that dead trees commonly occurred in the environments where the soil moisture content was low due to the high slope, amount of evaporation was high due to strong solar radiation as the location faced south, and the soil was dry due to strong solar radiation and short rain retention time. In other words, dead conifer trees in subalpine zones were concentrated in dry location environments, and the tendency was the same more than ten years ago.

• Journal of Korean Society of Forest Science
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• v.85 no.2
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• pp.316-324
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• 1996

This study was conducted by relative time study to identify the allowance time and basic work time, which is together composed of the total work time, in the wage composition and work process composition. This study was done for the case of a basic one person a group from thinning treatment for some conifer species such as Japanese red pine, Japanese larch, pitch pine and Korean pine. 1. In order to apply the Japanese allowance time of four species to the general conifer case, the maximum value of allowance time composition value among those of four species was selected. The results are as follows: delay time for person 1.8%, rest time 14.1%, delay time for machine 12.5% and wating time 0.4%. The some of ratios of adjustment allowance time is 28.8%. 2. Estimated wage basis time table, which can be used for wage table or process table, was prepared by adding up adjusted general allowance time and standard work time estimated by estimation equation for each species through the time study.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.2
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• pp.23-29
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• 2015

To fulfill the need for reuse indigenous tree to mitigate the elimination of nature forests due to road construction, one representative method for this reuse is to transplant them and re-establish in similar conditions. In order to investigate the transplant and establishment of indigenous tree, a correlation and regression analysis was conducted by species and tree size. Data were collected for 6 years(2008~2013) in 7 construction sites in cooperation with the Korea Expressway Corporation. Regarding the transplanted indigenous trees status, the success rate of transplant was 15,519(69%) of 22,521. The tree most transplanted was Pinus densiflora(15,562), followed by Quercus spp.(6,156), Prunus sargentii(235), and P. thunbergii(154). P. densiflora and P. thunbergii belong to the conifer group while Quercus spp., Prunus sargentii belong to the broadleaf group. As a result of a contrast test, the conifer group had a significantly lower success rate of transplant than the broadleaf group. In the relation of root collar diameter and success rate of transplant, there was the tendency that the larger the root collar diameter, the lower the success rate of transplant. This study demonstrated that there is a strong negative correlation between the two factors(r=-0.730, p>0.000). The predicted regression equation of the success rate of transplant was Y= -0.811X+88.627(X: root collar diameter, Y: success rate of transplant) and the $R^2$ value for the linear equation was 0.532.

• Journal of the Korean Professional Engineers Association
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• v.38 no.3
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• pp.1-5
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• 2005

As a method of anti-fire construction in forest region it is proposed to build fuelbreak(vegetated firebreak). Fuelbreak can separate the large area conifer forest into smell parts combined with natural firebreaks. Fuelbreaks can prevent forest fire effectively and also have other functions benefiting the forest ecosystem and environment. 3 kinds of construction skills are introduced for the silviculture technique to build fuelbreaks. And it is proposed to build the firebreaks network in national scale.

• Mycobiology
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• v.36 no.4
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• pp.211-216
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• 2008

During our studies on the diverse endophytic fungi resident on conifer needles, many species of Cladosporium previously unreported in Korea were encountered. In this paper, we report on two species of Cladosporium from the needles of pine trees (Pinus spp.). Based on analyses of internal transcribed spacer gene sequence, and cultural and micromorphological characteristics, they were identified as C. oxysporum and C. sphaerospermum. Both species have not been hitherto reported in Korea.

• Korean Journal of Environment and Ecology
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• v.19 no.4
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• pp.333-341
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• 2005

The Wonhyo tunnel section of the Gyeongbu line for KTX, which will be driven through the Cheonseongsan, has the opposing opinions between conservation and development. To investigate the vegetation structure of the Cheonseongsan area, sixty five plots(unit: $100m^2$) were set up and surveyed. The analysis results of the actual vegetation map was showing that the conifer-deciduous and deciduous community is $53\%$, And DGN 8 was $86.88\%$ in the analysis of Degree of Green Naturality. Five representative communities which are conifer-deciduous, de-ciduous, Pinus densiflora -Quercus dentata, P. densiflora-Q. acutissima and Q. dentata community, were investigated on a species composition.