• Journal of Ecology and Environment
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• v.46 no.1
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• pp.85-98
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• 2022

Background: Korean white pine (Pinus koraiensis) is a major commercial species, and the importance of the oak trees (Quercus spp.) is increasing due to various factors such as environmental and ecological values. However, more information is required to clearly understand the growth characteristics of these species especially regarding thinning intensity. This study was performed to provide the basic information to develop the silvicultural guideline and field manual by analyzing tree and stand characteristics in line with thinning intensity in the Korean white pine plantation and oak-dominated natural deciduous forest. Results: Diameter at breast height (DBH) and volume changes by the thinning intensity in the Korean white pine plantation were significantly different from those in the oak-dominated deciduous natural forest. In particular, DBH distribution in the pine stand appeared that there were more large diameter trees as the thinning intensity was higher. DBH periodic annual increment (PAI) of the pine stand was higher as the thinning intensity was stronger and the growth period was shorter. This trend was similarly shown in the natural deciduous forest, but the amount of PAI was smaller than in pine stand. The volume PAI after thinning was not decreased over time. In each stand type, the PAI tended to be lower as stand density was higher. The volume PAI in the pine stand was significantly higher than that in the oak-dominated natural deciduous forest. Dead trees occurred the most in the unthinned plots of each stand type, and those were higher in the natural deciduous forest. Ingrowth trees were observed only in the natural deciduous forest, and its distribution was the lowest in unthinned plots; Korean white pine as ingrowth occurred the most frequently among many tree species. Conclusions: Different effects of thinning treatment on DBH and volume PAI, mortality, and ingrowth were observed for each stand. With respect to forest growth, Korean white pine plantation was superior to the oak-dominated natural deciduous forest. The results of this study offer fundamental information for the development of silvicultural guidelines for Korean white pine plantations and oak-dominated natural deciduous forests in Korea.

• Journal of Korean Society of Forest Science
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• v.97 no.2
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• pp.156-164
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• 2008

Recognizing the importance of the multi-purpose management of natural deciduous forest, this study was carried out to implement the partial cutting for stand regulation to examine agroforestry practice as well as other concurrent forest resource production, and to investigate the changes in stand characteristics and understory vegetation in a silvopasture practiced natural deciduous stand in the Research Forest of Kangwon National University, Korea. Three different partial cutting intensities (68.1%, 48.6%, and control) were performed in the unmanaged natural deciduous stand in order to improve the growing condition, especially light condition, for introducing some commercial herbaceous plants on the forest floor to establish agroforestry and/or silvopastoral system. Dominated by Quercus varibilis Blume (50.5%) and Quercus dentata Thum. ex Murray (42.6%), eight tree species were composed of the study forest, including poles of Pinus desiflora Siebold & Zucc and sapling of Pinus Koraiensis Siebold & Zucc. The total of 87 (13 tree species, 12 shrub species, 58 herbaceous species, and 4 woody climbers) vascular plant species were observed in study site after partial cutting treatments, while that of before partial cutting was 53 species (14 tree species, 8 shrubs species, 30 herbaceous species, and 1 woody climbers). The proportion of life form spectra in plot B was Mi (28.4%)-Na (23.0%)-Ge (17.5%)-Ch (10.8%)-He (9.5%)-MM (6.7%)-Th (4.1%). No statistically significant differences were observed in changes of life form spectra from before to after partial cutting treatment and among partial cutting gradients in this study. Partial cutting and scratching for forage sowing made plants invade easily on the forest floor, and light partial cutting (LPC) plot (500 stems/ha) had much higher number of undersory species than those of heavy partial cutting (HPC) plot (310 stems/ha) and control plot (1,270 stems/ha).

• Journal of Korean Society of Forest Science
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• v.103 no.4
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• pp.613-621
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• 2014

This study was conducted to estimate the changes of stand diversity before and after applying three different silvicultural treatments such as selection cutting system, two-storied system, and shelterwood system. Data were collected in the natural deciduous forests in Pyungchang of Gangwon Province, Korea. Nine permanent sampling plots of 0.09 ha were established in the forests and the each of silvicultural treatments was applied to three sampling plots, respectively. Some tree variables were measured in each stand before and after the silvicultural treatments were applied. With these data, stand attributes were estimated in each stand before and after the silvicultural treatments. In this study, two different indices related to each of stand diversity indices such as contagion, DBH-difference, height-difference, and mingling were estimated and compared to analyze the differences of stand diversity among the stands before and after silvicultural treatments. As a result, total eight stand diversity indices were used to analyze the differences among structures of stands managed by three different silvicultural treatments. Duncan's multiple range test and t-test were then employed to statistically analyze the difference of stand diversity among the stands. The results revealed that stand structures seem to be improved after applying the silvicultural treatments. There are significant differences in the stand diversity indices between before and after silvicultural treatments for each stand. According to the evaluation of stand diversity indices, it was confirmed that spatial structure of the stands was improved by applying the silvicultural treatments.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.297-304
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• 2012

The objective of this study was to estimate the changes of stand structure before and after applying the three different silvicultural treatments such as selection cutting system, two-storied system, and shelterwood system. This study has been conducted in the natural deciduous forests in Pyungchang of Gangwon Province, Korea. Three permanent sampling plots of 0.09 ha were established in the forests and the three silvicultural treatments were applied in 2008. For this study, some tree variables were measured in each stand before and after the silvicultural treatments were applied. With these data, stand attributes were estimated in each stand before and after the silvicultural treatments. In this study, four stand structure indices were used to analyze the differences among structures of stands managed by three different silvicultural treatments. Contagion index, DBH-difference index, height-difference index, and mingling index were estimated and compared to analyze the differences of stand structures among the stands before and after silvicultural treatments. Duncan's multiple range test and t-test were then employed to statistically analyze the difference of stand structure among the stands. The results revealed that all of the stand structure indices seem to be increased after applying the silvicultural treatments. There are significant differences in the stand structure indices between before and after silvicultural treatments for each stand. According to the evaluation of stand structure indices, it was confirmed that spatial structure of the stands was improved by applying the silvicultural treatments. For attaining the specific goal of each stand types acquired by different silvicultural treatments, the frequencies and amounts of additional practices should be decided based on the changes of stand structure as time passed.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.427-433
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• 2015

This study was conducted to provide a method of establishing two-storied forests by the adjustment of stand structures in natural deciduous forests of Pyeongchang area. Three permanent sampling plots of 0.09 ha were established in study site and some tree variables were measured in each sampling plot before the treatment of two-storied system. Stand attributes and stand structures before treatment were estimated based on the data measured in sampling plots. The results indicate that the current stand status is different from typical stand structures of two-storied forests. A simulation technique was applied to predict stand attributes and stand structures after the treatment of two-storied system. Results suggest that significant time is required to accomplish target stand structures even after applying the treatment of two-storied system. Number of trees in the upper canopy class after treatment was predicted to be 170 trees/ha, which adequately meets the target of two-storied forests. It was predicted, however, that the lower canopy class trees has much less trees compared with the typical stand structures of two-storied forests. This problem could be solved with ingrowth of infant trees over time or by under-planting of tolerant species. It is confirmed that the target growing stock volumes of the upper canopy class should be approximately $150m^3/ha$ considering stand status after treatment. It is predicted that twenty years of conversion period is required to accomplish this goal. The changes in stand structures over time should be assessed based on stand inventory carried out every five years, and additional treatments for inducing two-storied forests should be applied if necessary.

• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.515-521
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• 2013

The objective of this study was to estimate the changes of stand structure before and after applying the three different silvicultural treatments such as selection cutting system, two-storied system, and shelterwood system. This study has been conducted in the natural deciduous forests in Pyeongchang of Gangwon Province, Korea. Nine permanent sampling plots of 0.09 ha were established in the forests and each of the three silvicultural treatments was applied to three sampling points. Some tree variables were measured in each stand before and after the silvicultural treatments were applied. With these data, stand attributes were estimated in each stand before and after applying the silvicultural treatments. In this study, a competition index was used to analyze the differences among structures of stands managed by three different silvicultural treatments. Hegyi's distance-dependent competition index was estimated and compared to analyze the differences of stand structures among the stands before and after silvicultural treatments. A method using a height angle $50^{\circ}$ from the base of the subject tree was adopted as the selection method of competitor trees. Duncan's multiple range test and t-test were then employed to statistically analyze the difference of stand structure among the stands. The results revealed that competition status among trees in the stand seems to be improved after applying the silvicultural treatments. There are significant differences in the competition index between before and after silvicultural treatments for each stand. According to the evaluation of competition index, it was confirmed that spatial structure of the stands was improved by applying the silvicultural treatments.

• Journal of Forest and Environmental Science
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• v.20 no.1
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• pp.40-50
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• 2004

This study was conducted to provide appropriate tending operation strategies for the natural deciduous forest, by the method of evaluating the stand quality, suggesting the removal plan for the undesirable trees, and predicting improvement cutting practice by tree quality evaluation. The results showed that average number of trees per ha was 717 stems, average DBH was 21.1cm. and average height was 13.6m. Canopy dominant species were in the order of Quercus serrata, Q. variabilis, Q. mongolica, Styrax obassia, and Ulmus davidiana var. japonica. Based on grades of four tree form factors for all tree in the study plots, we estimate the change of tree numbers. DBH and height with the improvement cutting by different tree grade. When the higher tree grade was applied to tending operation, the number of stem was decreased, but the values of DBH and height were not changed much, predicted to improve the stand quality.

• Journal of Korean Society of Forest Science
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• v.99 no.1
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• pp.136-143
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• 2010

This study was conducted to provide basic information on the management of natural deciduous forests by presenting suitable stand density over time for natural deciduous forests in Pyungchang Area. The stand density index(SDI) for the sampling point was also computed. The cutting scenarios were adopted by considering the SDI estimated in the sampling point. And then, simulation cutting was enforced to the stand. Cutting scenarios consisted of three cutting levels, with the period of 5 years where each suitable cutting level of selection system will not have the SDI over the maximum SDI throughout 30 years and consider harvest after 30 years. As a result of the simulation cutting, it was found that removing 12% and 14% of basal area per each time kept proper stand density while removing 10% exceed to the adequate basis. From an economic point of view, it was concluded that removal 12% of basal area would be the most suit cutting level in selection system.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.136-144
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• 2007

The objectives of this study were to compare nutrient input by throughfall, stemflow and litterfall and concentration of nutrient in soil water between deciduous forest stand and Larix kaempferi plantation at Mt. Joongwang, Pyongchang-gun, Gangwon-do. The amount of rainfall interception during study period in deciduous forest stand and L. kaempferi plantation was 12% and 36%, respectively. Concentrations of cation ($Na^+$, $Mg^{2+}$, $K^+$ and $Ca^{2+}$) in throughfall were not different, while concentration of $Cl^-$ in stemflow was higher in L. kaempferi plantation. The results indicated that annual nutrient inputs by rainfall with the exception of $Cl^-$ were significantly greater in deciduous forest stand. In soil water, concentrations of anion ($Cl^-$, $NO_3{^-}$ and $SO{_4}^{2-}$) in A-layer, and $Ca^{2+}$ and $Cl^-$ in B-layer were higher in L. kaempferi plantation. Litterfall input during study period was $2,589kg\;ha^{-1}$ in deciduous forest stand and $1,046kg\;ha^{-1}$ in L. kaempferi plantation. Concentration of N was higher in L. kaempferi plantation, while N input from litterfall was greater in the deciduous forest stand ($36.81kg\;ha^{-1}yr^{-1}$) than L. kaempferi plantation ($16.16kg\;ha^{-1}yr^{-1}$). $Na^+$, $Mg^{2+}$, $K^+$ and $Ca^{2+}$ in litterfall collected from deciduous forest stand were found to be higher than those from the L. kaempferi plantation. Also, input of those were greater in deciduous forest stand. Thus, total nutrient input by throughfall, stemflow and litterfall was greater in deciduous forest stand than L. kaempferi plantation, significantly.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.14-16
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• 2004

Although there have been wide range of studies to characterize forest stands based upon spectral information of satellite image, it was not fully understood the texture information of forest stand using high resolution data. The objective of this study is to evaluate several texture measures for characterizing forest stand structure, such as species composition, diameter at breast height(DBH), stand density, and age. High resolution IKONOS satellite imagery data were acquired in August 200 lover the forested area near Ulsan, Korea. Primary forest types were plantation pine, mixed forest, and natural deciduous forest of stand age ranging from 10 to 50 years old. Several GLCM-based texture measures were compared with forest stand characteristics. In overall, a texture measure (contrast) calculated using red band were better to differentiate species and age group than other texture measures and near infrared bands.