• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.3
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• pp.120-126
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• 2016

This study was carried out to examine the relationships between seasonal variations of soil $CO_2$ efflux rates and soil environmental factors in matured Pinus densiflora and Quercus variabilis stands in the Wola national experimental forests, southern Korea. Soil $CO_2$ efflux rates were measured monthly from March 2015 to February 2016. Mean soil $CO_2$ efflux rates during the study period were significantly higher in the Q. variabilis ($mean{\pm}standard$ error; $2.27{\pm}0.22{\mu}mol\;m^{-2}s^{-1}$) than in the P. densiflora ($1.63{\pm}0.12{\mu}mol\;m^{-2}s^{-1}$) stands. Mean soil water content and pH were also significantly higher in the Q. variabilis ($26.96{\pm}0.93%$, pH 5.19) than in the P. densiflora ($21.32{\pm}0.89%$, pH 4.87) stands, while soil temperature was not significantly different between the P. densiflora ($13.92{\pm}0.67^{\circ}C$) and in the Q. variabilis ($13.52{\pm}0.70^{\circ}C$) stands. $Q_{10}$ values were higher in the Q. variabilis (3.35) than in the P. densiflora (2.72) stands. The results indicate that soil $CO_2$ efflux rates in Q. variabilis stand could be more sensitive by the change of soil temperature compared with P. densiflora stand under a similar site environmental condition.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.543-548
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• 2015

We studied the genetic impact of natural regeneration practices, such as Single seed tree, Group seed tree, Patch clear cutting and Alternate strip clear cutting systems, by comparing the nuclear microsatellite(nSSR) variation of post-practice natural regeneration one-year old seedlings of Pinus densiflora to that of pre-practice mature trees. The levels of genetic diversity of seedlings (A=13.6, $A_e$=4.3, $H_o$=0.571, $H_e$=0.597) were similar to those of mature trees (A=13.4, $A_e$=4.3, $H_o$=0.596, $H_e$=0.598) and the differences in the level of genetic diversity between seedlings and mature trees for each of the practices were not statistically significant. The degree of genetic differentiation between seedlings and mature trees was very low ($F_{ST}$=0.002) and the pairwise $F_{ST}$ values between seedlings and mature trees for all practices were less than 0.01. Overall, the natural regeneration practices appeared to have only minor impacts on the genetic diversity and the genetic composition in the studied P. densiflora stands. For a better understanding of the genetic effects of natural regeneration practices, subsequent studies such as temporal genetic variation of seedlings formed by crossing among post-practice mature trees should be considered.

• The Korean Journal of Mycology
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• v.11 no.1
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• pp.9-13
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• 1983

Ectomycorrhizal fungi in Pinus $rigida{\times}taeda$ and poplar stands (Populus $alba{\times}glandulosa$ and others) were collected in 1981 and 1982. A total of 39 mushrooms representing 15 genera were identified from the pine stand, and the major genera were Amanita, Lactarius, Russula, Laccaria, and Boletus. From the poplar stands 16 mushrooms representing 8 genera were identified and 13 of them were the same found in the pine stand. Amanita, Russula, Laccaria, and Leccinum are the major genera in the poplar stands. A single species of Boletus was found in large number in pine and poplar stands. Lactarius was not observed in the poplar stands, while Leccinum was not found in the pine stand. Cantharellus lutescens which has not been reported in Korea was collected in the pine stand.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2001.06a
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• pp.181-185
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• 2001

경제개발과 함께 중화학 공장의 건설, 화력발전 그리고 자동차 등에 의한 화석연료의 급격한 사용의 증대와 인구의 도시 집중화는 공업지역 등 대도시 지역에 있어서 급격히 대기오염을 증대 시켰다. 황산화물의 농도는 도시와 공업지대에서 증가하고 있고, 질소산화물의 오염은 넓은 지역으로 이동하여 직ㆍ간접적인 대기오염의 피해를 가져오고 있다.(중략)

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2002.11a
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• pp.97-100
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• 2002

산업사회로의 급속한 발전에 따른 인위적인 환경오염 중에서 산성강우에 의한 자연환경 및 생태계의 심각한 문제로 대두되고 있다. 이러한 대기오염물질은 대기 중에 부유하면서 직접적인 피해를 주기도 하지만, 비, 눈 등의 강수현상에 의해 응결ㆍ낙하(rainout)되거나, 세정작용(washout)으로써 강수 내 화학성분의 변화를 초래한다고 하였다(박종길과 황용식, 1997).(중략)

• Journal of Korean Society of Forest Science
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• v.109 no.3
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• pp.300-312
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• 2020

The growing stocks of young forests that are less than10 years of age have been excluded from the Korean forest resource statistics, despite the existence of standing trees; however, sustainable forest management and carbon removals in the forestry section require complete information regarding forest resources. This study developed a method to estimate the growing stocks for young forests from National Forest Inventory (NFI) data. After reviewing previous research on growth characteristics for young forests, we conducted stem analysis of major species, and examined stand characteristics by site index, based on real yield tables. Our statistical analysis results showed that there were few standing trees with diameters at breast height (DBH) above 6 cm in young stands, and that it would have taken 12 years, on average, to reach 6 cm DBH. This suggests that mean tree height by diameter should be assessed at the root, in order to assess growing stocks for young stands through the NFI. Moreover, the database system should be improved to differentiate tree species, since diverse shrubs, including trees, have been surveyed.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.138-147
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• 2012

For biomass estimation of Phyllostachys pubescens stands by optimal survey method we established 9 bamboo sample plots in the research forests of KFRI (Korea Forest Research Institute). The dry weight of culm segment determined by relative heights of total bamboo height show us two groups of 1st to 5th culm segment (up to 0~55% culm of tree height from the bottom area) and 6th to 8th culm segment (55~100%) by the results of cluster analysis for dry weight ratio. This results show that upper and lower part of 55~70% reference height from the bottom area against total culm height can be used in obtaining 1 kg of a sample bamboo, respectively, rather than 2.0 m stem segments of other forest tree species. In above-ground biomass estimation by $W=aD+bD^2$ having the highest coefficient of determination in this study, above ground stand biomass was 57.77 ton/ha (culm 40.47 ton/ha, branch 9.29 ton/ha, and leaf 8.01 ton/ha) of which 70% was contributed by culm component followed by branch (16%) and leaf (14%). Below-ground biomass was 53.35 ton/ha in total.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.461-467
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• 2020

The aim of this study was to utilize Kozak's stem taper model to develop both a stem taper equation and a stem volume table for Criptomeria japonica, a tree species distributed across Korea. A total of 1,000 sample trees were cut and collected across the country to measure their diameters by stem height. The equation was then used to estimate examine their stem shapes. Our results show that the Fitness Index for the equation was 98.7%, the Mean Absolute Deviation (MAD) was -0.0142, and the MAD was 1.1640, thus indicating a high level of fitness. A statistically significant difference (p < 0.05) was also found from the analysis of discrepancies between a current table and the new table used in this study. It is therefore suggested that the new table-with data from actual stands-will contribute to enhancing the accuracy of national and municipal forest statistics and reducing losses caused by imprecise data on available forest resources.

• Journal of agriculture & life science
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• v.50 no.1
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• pp.73-81
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• 2016

The objectives of this study were to determine the effects of thinning intensity on the changes of vegetation structure in Japanese Evergreen Oak(Quercus acuta Thunb.) stands in Wando-arboretum. The flora were composed of 24 families, 33 genera, and 36species in thinned sites. The dominant layer of control site showed higher number of plant species than that of treatment sites. On the while, the sub-dominant layer, shrub layer, and herbaceous layer treatment sites showed higher number of plant species than control site. According to the analysis of importance value, Q. acuta in the dominant layer, Q. acuta and Camellia japonica in sub-dominant layer, and Camellia japonica in shrub layer showed the highest importance values, respectively. The importance value of Trachelospermum asiaticum was the highest in the herbaceous layer. According to the results, species diversity was higher in descending order of heavy thinning, light thinning, and control. This result could be explained by increased light transmissions from higher thinning intensity than in other treatments. In this context, the results of this study may be useful for selecting appropriate tending methods in terms of forest management and biodiversity conservation.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.477-483
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• 2020

We constructed a stand yield table for Chamaecyparis obtusa based on data from an actual forest. The previous stand yield table had a number of disadvantages because it was based on actual forest information. In the present study we used data from more than 200 sampling plots in a stand of Chamaecyparis obtusa. The analysis included theestimation, recovery and prediction of the distribution of values for diameter at breast height (DBH), and the result is a valuable process for the preparation ofstand yield tables. The DBH distribution model uses a Weibull function, and the site index (base age: 30 years), the standard for assessing forest productivity, was derived using the Chapman-Richards formula. Several estimation formulas for the preparation of the stand yield table were considered for the fitness index, and the optimal formula was chosen. The analysis shows that the site index is in the range of 10 to 18 in the Chamaecyparis obtusa stand. The estimated stand volume of each sample plot was found to have an accuracy of 62%. According to the residuals analysis, the stands showed even distribution around zero, which indicates that the results are useful in the field. Comparing the table constructed in this study to the existing stand yield table, we found that our table yielded comparatively higher values for growth. This is probably because the existing analysis data used a small amount of research data that did not properly reflect. We hope that the stand yield table of Chamaecyparis obtusa, a representative species of southern regions, will be widely used for forest management. As these forests stabilize and growth progresses, we plan to construct an additional yield table applicable to the production of developed stands.