• Journal of Korean Society of Forest Science
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• v.86 no.2
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• pp.158-166
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• 1997

This study presents the method to quantify the stand structure diversity or homogeneity. Gadow's dbh differentiation(Durchmesserdifferenzierung) is introduced which quantifies the horizontal stand structure by the ratio of the dbh between subject tree and neighbour trees. And new stand structure diversity index based on Lorenz curve, which is made by ratio of tree number and basal area or volume by dbh class, is presented. The horizontal stand structure index based on Lorenz curve has a value from 0 to 1 as Gadow's index, and approximates to 1 if the stand structure has high diversity. In the comparative analysis for performance, the new stand structure index based on Lorenz curve is considered to compare with the Gadow's index for describing the stand structure.

• 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 Korean Society of Forest Science
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• v.112 no.2
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• pp.209-216
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• 2023

This study aimed to use national forest inventory data to develop a forest productivity index and yield prediction model of a Tilia amurensis stand. The site index displaying the forest productivity of the Tilia amurensis stand was developed as a Schumacher model, and the site index classification curve was generated from the model results; its distribution growth in Korea ranged from 8-16. The growth model using age as an independent variable for breast height and height diameter estimation was derived from the Chapman-Richards and Weibull model. The Fitness Indices of the estimation models were 0.32 and 0.11, respectively, which were generally low values, but the estimation-equation residuals were evenly distributed around 0, so we judged that there would be no issue in applying the equation. The stand basal area and site index of the Tilia amurensis stand had the greatest effect on the stand-volume change. These two factors were used to derive the Tilia amurensis stand yield model, and the model's determination coefficient was approximately 94%. After verifying the residual normality of the equation and autocorrelation of the growth factors in the yield model, no particular problems were observed. Finally, the growth and yield models of the Tilia amurensis stand were used to produce the makeshift stand yield table. According to this table, when the Tilia amurensis stand is 70 years old, the estimated stand-volume per hectare would be approximately 208 m³ . It is expected that these study results will be helpful for decision-making of Tilia amurensis stands management, which have high value as a forest resource for honey and timber.

• Journal of Korean Society of Forest Science
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• v.98 no.3
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• pp.225-230
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• 2009

Using dynamic programming, which is one of operations research techniques, the best pathway was chosen to maximize the total harvest volume for a Korean white pine (Pinus koraiensis) stand. This study was carried out in an age class III at Chuncheon National Forest, Gangwon province. That stand was assumed to apply 3 different thinning intensities of none, 30% and 50% thinnings. These thinning pathways are planned to implement two times, of thinning at 35 age and 55 age. The final cutting (rotation age) is assumed to carry out in 70 years. A growth function for Korean white pine stand was developed with forest inventory data, the volume was calculated with this growth function. As a result, the best thinning pathway for this Korean white pine stand using dynamic programming is to implement 30% at the first thinning and 50%at the second thinning.

• Journal of Korean Society of Forest Science
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• v.76 no.3
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• pp.181-192
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• 1987

The purpose of this study is to develop the method of stand volume estimation by the plotless sampling method. The required data were obtained from 164 sampling plots in the red pine(Pinus densiflora) stands which were located in Kyeong-gi, Chung-nam, Chung-buk and Kang-won areas, and related factors were measured actually. The method of stand volume estimation and several tables were drivel from these data. 1. The relationship between the values of stand average height, basal area per ha, and basal area height obtained from the plotless sampling method and values measured actually could be described by the equation Y=bx, where b approached nearly 1.0 and there were no significant differences between them. Therefore stand volumes could be estimated by the plotless sampling method. 2. The estimated equations of the stand voulumes, which were estimated using factors to be measured by dendrometer, are as follows ; logV=-0.0208+0.8497 logGH, logV=-0.0028+0.7981 logG+0.9313 logH. Stand volume tables by these estimated equations were shown in table 4, 5 and estimation error percentages were 9.16% and 8.50% respectively. FH=D/(1.5205+0.0994D) logFH=0.0451+0.2429 logD+0.3474 logH logFG=-0.0380+0.7758logG-0.0066logH F=H/ (-5.1697+2.6013H) F=FH/(-3.1256+2.7611FH) logF=-0.0634-0.0848 logGH-0.1224 logDi 4. Stand form height tables(table7, 8), form basal area tables(table 9), and stand form factor tables(table 10, 11) were prepared using the above estimated equations, and the estimation error percentages were less than 10%.

• Journal of Korean Society of Forest Science
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• v.79 no.4
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• pp.388-397
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• 1990

This study was conducted to investigate the changes of land use and stand volume around Mt. Kuem-O by B/W aerial photographs in 1979 and B/W Infrared aerial photographs in 1988. The results obtained in this study were as follow : 1. In classification of forest type on aerial photographs, coniferous stand was dark tone and hardwood stand was light tone and irregularly rounded crowns. 2. In classification of coniferous stand, Pinus densiflora was narraw cone and rounded tip of crowns and rough texture, Pinus rigida was irregulary rounded and broadly conical crowns. 3. To refer to changes of forest land area, mixed forest was changed into P. desiflora (687ha), P. rigida (130ha) and hardwood stand (219ha). 4. The regression equations between crown diameter and DBH were significant at 1% level by F-test in all stands. So the equation, D=a+bCD was used to estimate DBH. 5. The tree height curve equations were significant at 1% level by F-test in all stands. To estimate tree height the equation, logH=loga+blogD was adopted in P. densiflora and L. leptolepis and $H=a-bD+cD^2$ was adopted in P. rigida, hardwood stand and mixed forest. 6. The highest volume per hectare was observed in L. leptolepis and mixed forest showed the greatest growth percentage, while the lowest volume per hectare and growth percentage were observed in hardwood stand.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.613-621
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• 2022

The study aim was to investigate changes in the diameter, number of standing trees, stand volume per ha and site index by the forest survey order, climate zone (northern temperate, central temperate, southern temperate, and warm temperate regions), and altitude in 100 m intervals) by collecting samples of Robinia pseudoacacia from the fifth, sixth, and seventh national forest survey datasets. The rotation cutting age, which is a standard used for wood, was calculated. The changes were statistically analyzed by performing ANOVA and the Duncan multiple test. Diameter growth naturally increased according to the forest survey order and was lowest in the southern temperate region by climate zone and lowest at the 301-400 m altitude. The number of standing trees per ha did not change according to the forest survey order and altitude, and the density was highest in the central temperate region and lowest in the southern temperate region. The stand volume per ha increased according to the forest survey order, and the climate zone was divided into two groups: ① northern temperate region and central temperate region, ② southern temperate region and warm temperate region. The stand volume growth was highest at the 201-300 m point. Thesite index showed results similar to the change pattern of the stand volume per ha. The growth curve, which can be seen by the change in stand volume per ha, was estimated by applying theWeibull formula, and the stand volume per ha was estimated to reach approximately 200 m³/ha at 50-60 years. The rotation of the highest production in volume, which is the standard for using trees as wood rather than honey sources, was calculated to be 34 years.

• Journal of Korean Society of Forest Science
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• v.96 no.6
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• pp.742-749
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• 2007

The objective of this study was to develop thinning effect analysis model (TEAM) using individual-tree distance-independent growth model of Pinus koraiensis Stands. The TEAM was designed to analyze thinning effects associated with such thinning prescriptions as the number, timing, intensity, and method of thinnings. To testing TEAM application, stand growth effects were compared with seven scenarios according to thinning prescription plan. In the results, it was possible to estimate the number of trees, height, volume with diameter (DBH) class of individual trees, and average diameter growth, height growth, the number of trees and volume growth per ha of stands. The result of sensitivity analysis on one Pinus koraiensis stand, it was not sure to expect the much more volume at the rotation age by stand density control applying thinning prescription. In the case of thinning, total yield volume has much more $40{\sim}75m^3$ per ha, within 5 cm in average diameter growth and within 1 m in average height growth than thats of non-thinning over increasing stand age. TEAM, as decision making support system, can be used for selecting the thinning prescription trial and determining one of some thinning prescription plan in different site specific stand environments.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.1
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• pp.28-33
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• 2003

In this study, we observed air temperature to make clear that land coverage condition and stand form has a certain relationship to air temperature during the night in various green space. And with revolution analysis, we interpreted relationship of air temperature distribution in the green space, The way of analysis is this land coverage rate and air temperature, of number of tree volume of tree air temperature. With this experimental result, we can propose green plan, which is taking into consideration lower effect of air temperature. In this result, lower zone is formed in forest and water area, higher zone is formed in paved surface and barren ground. but this gap is a little. arbor+subarbor area, in the point of water area surrounded stand is formed relative lower air temperature. As a result to make up efficiency lower air temperature area, it is needed to make water area which has surrounded forest, and it is needed to make stand form lower air temperature 2~3 layer forest. In order of arbor, subarbor, shrub, the lower air temperature is more effect.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.9-21
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• 1983

The structures of oak stands were studied in relation to their productivity. Three plots classified by the site quality following to altitude, were selected on the oak stand located at Naryongri Eunsanmyun Buyeogun. The site qualities of the stand studied were generally estimated to be moderate in respect to some soil physical and chemical properties. Quercus variabilis was dominant species in the vegetation composition of the stand studied. The crown densities of the stand were varied from 65.4% in plot I to 78.2% in plot III and the parts, occupied with oak trees, ranged from 44.4% in plot I to 65.9% in plot III in the density. In the contrast to crown density, the growing stocks of oak trees ranged from $3.937m^3$ in plot I (73.4% of plot total) to $2.075m^3$ in plot III (84.3% of plot total). The occupied ratios, measured by crown class, exhibited dissimilarity between crown projection area and volume, and also the ratios brought into different patterns by plot. Highly significant correlations were proved between crown projection areas and volumes of individual oak trees by plot, but not proved in the relations by crown class. The cumulative growth, current annual increment and mean annual increment displayed various patterns by plot and by crown class in the heights, D. B. H. s and volumes of oak trees. The maximum values of current annual increment of height were generally recorded in 10 to 20 years, earlier than those of D. B. H. The mean annual increment of height, D. B. H. and volume maintained similar levels after about 10 years and fluctuated irregularly. The crown projection area and volume following to thinning decreased in the order of the thinning methods of grade A < grade B < crown thinning$90m^3/ha$ in about 40 years in the productivity of volume of the oak stand studied.