• 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.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.435-440
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• 2002

The objective of this study is to analyze the relationship between polarimetric radar backscatters and stand characteristics over the mountainous forest area. L- and P-band full polarimetric airborne SAR data obtained in September 2000 were processed to compare with forest stand maps and ground collected stand variables. After the geometric registration of SAR image, mean radar backscatters were extracted for those ground plots where the stand parameters, such as tree height, DBH, and basal area, were measured during and after the SAR data acquisition. Preliminary analysis was focused on the topographic influence of radar backscattering under the homogeneous forest stand condition. Topographic effects, assessed by the local incidence angles, were different obvious in L-band data while it was not clear with P-band data.

• 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.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.332-335
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• 2008

Newly developing SAR (Synthetic Aperture Radar) sensors commonly include high resolution X-band those data are expected to contribute various applications. Recent few studies are presenting potential of X-band SAR data in forest related application. This study tried to investigate the relationship between forest stand parameters and multi-band SAR normalized backscattering. Multi-band SAR data was radiometric corrected to compare signal from different forest stand condition. Then correlation coefficients were estimated between attribute of forest stand map and normalized backscattering coefficients. Although overall correlation coefficients are not high, only X-band shows strong relationship with DBH class than other bands. The signal of C- and L-band is composed of a large number of discrete tree components such as leaves, stems, even background soil. In forest, strength of radar backscattering is affected by complex parameters. Further study might be considered more various forest stand parameters such as canopy density, stand height, volume, and biomass.

• Journal of Forest and Environmental Science
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• v.24 no.3
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• pp.165-169
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• 2008

This study attempts to analyze the relationship between forest volume and age based on 5th NFI data and spectral characteristics of satellite imagery using ASTER sensor in Korea. Forest stand volume and age had the negative correlation with the spectral reflectance in all of the band (Blue, Green, Red, SWIR). With increasing of stand volume and age, spectral reflectance decrease. The spectral reflectance of band1 showed the highest correlation between stand volume and spectral reflectance among the VNIR wavelength. The spectral reflectance band 1, 2 (visible wavelength) and stand age have high correlation compared to other bands. The correlation coefficients between forest volume and vegetation indices have low relationship. This result indicates that the reflectance of blue band may be important factor to improve the potential of optical remote sensing data to estimate forest volume and age.

• 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).

• The Korean Journal of Ecology
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• v.23 no.6
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• pp.435-438
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• 2000

Diameter distributions describe forest stand structure information. Prediction equations for percentiles of diameter distribution and parameter recovery procedures for the Weibull distribution function based on four percentile equations were applied to develop prediction system of even-aged slash pine stand structure development in terms of the number of stems per diameter class changes. Four percentiles of the cumulative diameter distribution were predicted as a function of stand characteristics. The predicted diameter distributions were tested against the observed diameter distributions using the Kolmogorov-Smirnov two sample test at the ${\alpha}$=0.05 level. Statistically, no significant differences were detected based on the data from 236 evaluation data sets. This stand level diameter distribution prediction system will be useful in slash pine stand structure modeling and in updating forest inventories for the long-term forest management planning.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.83-90
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• 2012

This study was undertaken to analyze 1) the growth characteristics for the optimal planting density and 2) reached ages of sap tapping for the planting timing of Acer okamotoanum in natural and plantation stand. Soil in natural stand was significantly more fertile than that of plantation stand. Early growth of A. okamotoanum in plantation stand was affected by planting density. Results showed that there was a positive relationship between the DBH and crown width in both natural and plantation stands. Reached ages by DBH were no significant difference in natural stands. Reached ages on DBH 10 cm were approximately 19 and 9 in natural and plantation stands, respectively.

• The Korean Journal of Quaternary Research
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• v.18 no.2 s.23
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• pp.107-107
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• 2004

In this paper we have introduced some results of study on stand growth pattern and stand structure of larch forest which are located in selected forest sites of Khangai and Gobi-Altai mountain ranges of Mongolia. Our investigations showed that growth intensity and stand structure in western Mongolia are very specific from the other forest vegetation zones of Mongolia. Studies on the stand structure and growth trend indicate that tree types of stand structure and different types of growth of Larix sibrica are very common in Western Mongolia. These peculiarities of stand structure and growth of larch stands in Western Monolia could be used for inventory work and an improvement of the forest management in Western Mongolian region. The larch tree is the dominant tree species in Western Mogolia. Forest cover of the region is about 15%, which is two times higher than the country's average. In this region forest area is divided into 4 forest sub-regions: the Central Khangai, Western Khangai, North Eastern Khangai and South Easterun Khangai sub-regions including taiga, pseudo taiga, sub taiga, sub-alpine and forest steppe belts. Silviculture practices and forest research management request to study forest growth trends in local and general conditions, which means to indicate a change of taxonomic characteristics of stand from time to time including diameter, height, basal area, growth stock etc. The forest management practice mostly uses tables of forest growth and yield based on the results of long term research on forest growth. Forest yield tables and other relevant forest standards of Russia are used for the forest inventory and forest management. They are not able to determine forest structure and growth peculiatities of Mongolian forests. Studies on forest resource assessment in Mongolia indicate that after logging operations and forest fires the natural regeneration of desired species such as pine and larch often does not succeed. This situation forces to take a different approach of forest management and silviculture practice depending on the stand structure and growth rate of the forest stands. According to our investigation in last years, forest growth pattern of larch forest depends mostly on stand structure, stand age and growth condition including forest soil, climate and location in different slopes. Due to improve environmental function of forest ecosystem in the region, it is needed to conduct very comprehensive study of high mountain forest ecosystem in selected sub-regions.

• Journal of Forest and Environmental Science
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• v.35 no.3
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• pp.197-204
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• 2019

A tree-length harvesting system using the HAM300, which is mounted on a farm tractor prototype machine, have been recently introduced in South Korea for thinning old (>30 years) forests. However, no research has previously been conducted on the characteristics of residual stand damage associated with cable yarding systems on thinning treatment stands in South Korea. Therefore, there were assessed on the degree and quantity of residual stand damage caused by felling and yarding process to broaden the knowledge of residual stand damage on semi-mechanized skyline thinning operations. This study investigated scar size, direction, area, shape type and their distribution on the residual stand damage caused by felling and yarding operations. Damage to residual trees was generated for 7.4% and 6.9% of residual trees in felling and yarding operations, respectively. Damaged direction of scars was located in front-side (38.9%) and up-side (34.7%) for felling operations while the highest scar damage was found on down-side (44.6%) for yarding operations. Scar heights of felling damage were higher than those of yarding damage. In yarding operation, the most of the scars was located within l0m from the center of the skyline corridor. These results should be useful information for forest managers and landowners to reduce residual stand damages and retain valuable timber volume from thinning treatments.