• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.22 no.6
• /
• pp.1-14
• /
• 2019

Carbon storage is one of the regulating ecosystem services provided by urban street trees. It is important that evaluating the economic value of ecosystem services accurately. The carbon storage of street trees was calculated by measuring the morphological parameter on the field. As the method is labor-intensive and time-consuming for the macro-scale research, remote sensing has been more widely used. The airborne Light Detection And Ranging (LiDAR) is used in obtaining the point clouds data of a densely planted area and extracting individual trees for the carbon storage estimation. However, the LiDAR has limitations such as high cost and complicated operations. In addition, trees change over time they need to be frequently. Therefore, Structure from Motion (SfM) photogrammetry with unmanned Aerial Vehicle (UAV) is a more suitable method for obtaining point clouds data. In this paper, a UAV loaded with a digital camera was employed to take oblique aerial images for generating point cloud of street trees. We extracted the diameter of breast height (DBH) from generated point cloud data to calculate the carbon storage. We compared DBH calculated from UAV data and measured data from the field in the selected area. The calculated DBH was used to estimate the carbon storage of street trees in the study area using a regression model. The results demonstrate the feasibility and effectiveness of applying UAV imagery and SfM technique to the carbon storage estimation of street trees. The technique can contribute to efficiently building inventories of the carbon storage of street trees in urban areas.

• Journal of Korean Society of Forest Science
• /
• v.105 no.3
• /
• pp.336-341
• /
• 2016

The object of this study was to classify the local types in relation to regional differences using Height-DBH growth of Pinus densiflora in Korea. The regional types were clustered according to Getis-Ord's $G_i$ among Local indicators of spatial association (LISA) by characteristics of spatial distribution which were calculated the residual of sample plots by fitting Height-DBH growth model using Weibull growth equation. Accordingly, Pinus densiflora were classified 3 groups, It indicated that annual precipitation had one of the biggest impacts among the considered site and climate factors. This results can become the standard for regional management of Pinus densiflora forests.

• Journal of Korean Society of Forest Science
• /
• v.97 no.4
• /
• pp.368-373
• /
• 2008

The objectives of this study were to validate existing growth models of Pinus densiflora and Larix leptolepis grown in Chonbuk regions, and to examine suitability of models to different regions using spatially varied data set. In the valuating model predicted of Pinus densiflora, except to DBH growth model, basal area and height prediction models were biased to fit to different region. And in the valuating predicted height, basal area and DBH model of Larix leptolepis, they were adequate to new data set acquired from different region. Therefore, existing prediction models, except DBH model, of Pinus densiflora have the limitation of practicality that could not be suitable for application to different region. However, owing to high compatibility shown predicted DBH, basal area and height models of Larix leptolepis, they will be adequate to use as the prediction models where data are available around eastern mountain areas of Jeollabukdo.

• Journal of agriculture & life science
• /
• v.45 no.2
• /
• pp.51-59
• /
• 2011

This study was conducted to analysis the growth characteristics and the diameter at breast height (10 cm) reached ages in natural stand and platation for the optimal planting density and planting timing of Acer mono for. rubripes. There was high correlation between the DBH and crown diameter (E-W: r=0.82, S-N: r=0.76) in natural stand, and between the DBH and crown diameter (E-W: r=0.76, S-N: r=0.90) in plantation. In natural stand, average reached age on DBH 10 cm was $21.1{\pm}7.0$, and was $9.2{\pm}1.3$ in plantation. Therefore, the collectable timing of sap in artificial planting short approximately 2.3 times over the natural regeneration.

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

• Journal of Ecology and Environment
• /
• v.46 no.1
• /
• pp.85-98
• /
• 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 Forest and Environmental Science
• /
• v.24 no.1
• /
• pp.41-46
• /
• 2008

Progeny tests of Abies holophylla were established with 32 open-pollinated families at Hwaseong and Gangneung in 1994. Growth characteristics (height, DBH and volume index) were measured at the age of 15, showing that Gangneung site showed in general better performance than Hwaseong site. Analysis of variance (ANOVA) of the growth characteristics showed that there was a significant difference among families in Gangneung but not in Hwaseong, and Hwaseong site showed that DBH and volume index were statistically different among replications. At Gangneung site, family ${\times}$ replication interaction was significant in DBH and volume index. Based on the combined analysis of both sites, all characteristics except height showed highly significant differences between sites and among families. On the other hand, family ${\times}$ replication interaction was not significant, implying that growth pattern of families could be similar at Gangneung and Hwaseong. Individual heritabilities ($hi^2$) at Gangneung were 0.485 in height, 0.611 in DBH and 0.538 in volume index, and the values of $hi^2$ at Hwaseong were 0.121 in height, 0.054 in DBH and 0.080 in volume index, respectively. Based on both sites, $hi^2$ was estimated as 0.204 in height, 0.326 in DBH and 0.238 in volume index. Individual heritabilities (0.054~0.611) were lower than family heritabilities (0.089~0.723) for all growth characteristics. Realized gain was estimated to be 2.5% in height, 9.2% in DBH and 23.6% in volume. When inferior families (about 50% of all families) are genetically thinned from a seed orchard, genetic gain would be 9.55% in height, 17.0% in DBH and 46.8% in volume.

• Journal of Korean Society of Forest Science
• /
• v.94 no.6
• /
• pp.410-419
• /
• 2005

Community structure of evergreen broad-leaved forest of Mt. Yeogwi in Jin-do was investigated to secure sustainable conservation of evergreen broad-leaved forest. Twenty survey plots of $20m{\times}20m$ were established along the elevation from 200 m to 390 m above the sea level in the northwestern slope. The woody species were tallied at each plots. DBH distribution of the major evergreen broad-leaved trees was investigated to find out the spatial distribution. Cluster analysis was applied to a set of vegetation data, that is, importance value to classify the forest community. Species diversity, evenness and species correlation were analysed. Canonical correspondence analysis was also applied to vegetation data and soil environmental data. Cluster analysis showed that the forests of Mt. Yeogwi were classified into 2 community groups, such as Camellia japonica community group and Quercus acuta community group. C japonica community group was subdivided into C japonica- evergreen broad-leaved trees community, C. japonica-Neolitsea sericea community, and C. japonica-deciduous broad-leaved trees community. Q. acuta community group was subdivided into Q. acuta-C. japonica community, and Q. acuta community. C. japonica, Q. acuta, N. sericea, Machilus thunbergii and Illicium religiosum were dominant evergreen broad-leaved tree species, while Styrax japonica, Lindera erythrocarpa, Cornus kousa, Prunus sargentii, Albizzia julibrisin and Quercus acutissima were major deciduous tree species. Species diversity was greater in Q. acuta community group (0.8231 for Q. acuta-C. japonica community, and 0.8135 for Q. acuta community) than in C. japonica community group (0.7674 for C. japonica-evergreen broad-leaved trees community, 0.6164 for C. japonica-N. sericea community, and 0.7931 for C. japonica-deciduous broad-leaved trees community). DBH 2 cm~10 cm of major evergreen broad-leaved trees occupied 80% of all. C. japonica of less than DBH 5 cm tended to aggregate but distribute randomly or regularly with increasing DBH. Q. acuta distributed more aggregately than C. japonica and Machilus thunbergii for more than 15 cm of DBH. C. japonica correlated negatively with Q. acuta, I. religiosum and C. kousa, but positively with N. sericea. with significance at 1% level. Q. acuta correlated negatively with C. japonica, N. sericea and M. thunbergii but positively with l. religiosum. There were also negative correlation between N. sericea and C. kousa. CCA showed that forest communities were correlated with soil variables such as CEC, soil organic matter and soil pH. With increased soil organic matter and CEC, and decreased soil pH, C. japonica was dominant and forest community and Q. acuta and N. sericea tended to develop in the evergreen broad-leaved forest.

• Journal of Korean Society of Forest Science
• /
• v.112 no.1
• /
• pp.71-82
• /
• 2023

Forest biomass is used as a representative indicator of forest size, maturity, and productivity. Therefore, quantitative evaluation is important for management and harvest as well as the evaluation of ecosystem functions and services including CO₂ absorption. The allometric equation is a widely used method for estimating the value of each component through the relative growth rate of plants. Recently, studies indicated that the relative growth of trees is changing because of the increased CO₂ concentration in the atmosphere and the resulting climate change, raising the need to review the previously developed relative growth models and coefficients. In this study, the height-diameter at breast height (DBH) relationships of four major tree species in Korea [(Pinus densiflora (PD), Larix kaempferi (LK), Quercus variabilis (QV), and Quercus mongolica (QM)] were analyzed using the 5th-7th National Forest Inventory (NFI) data. Furthermore, these results were compared with the present yield table from the National Institute for Forest Science. This analysis revealed that the expected height for the same DBH increased as the NFI progressed. For example, in model analysis, the expected heights for PD, LK, QV, and QM for DBH of 25 cm were 12.48, 19.17, 14.47, and 13.19 m, respectively, in the 5th NFI data. In the 7th NFI data, these values were estimated as 13.61 (+9.1%), 21.58 (+12.7%), 15.76 (+8.9%), and 13.93 m (+5.6%), respectively. These results indicate that the major tree species in South Korean forests currently are more vigorous in height growth than in diameter growth when compared to the height-DBH development trends by tree species identified through past survey data.

• Journal of Korean Society of Forest Science
• /
• v.111 no.1
• /
• pp.150-164
• /
• 2022

This study was conducted to provide basic information for the development of silvicultural guidelines and manuals. This was achieved through analysis of tree and stand characteristics according to the first and second thinning in Korean white pine plantations. Data were collected from permanent plots installed at Korean white pine plantations according to thinning intensity, and residual tree and stand variables, including diameter at breast height (DBH), volume, and mortality at age 19-43, were analyzed using data repeatedly collected in 4-5 measurements by experiments. According to one-way variance of analysis, tree DBH and volume were significantly different according to thinning intensity (p<0.05). DBH distribution was skewed to the left side over time as thinning intensity was heavier. Thus, tree DBH values were larger in heavy thinning plots with increased age. The periodic annual increment (PAI) of DBH was higher with heavier thinning intensity and fewer years after thinning. The PAI range by thinning intensity was 0.48-0.95 cm/year at age 19-24. In addition, the PAI increased in heavy thinning plots after the second thinning; The PAI range by thinning intensity was 0.29-0.67 cm/year after the second thinning at age 37-42. The PAI of tree volume differed according to thinning intensity, and the PAI value did not decrease obviously, in contrast to the pattern of the DBH PAI. Stand volume was generally higher in high-density stands, and the PAI of stand volume was high in unthinned and light thinning plots. Mortality was highest in unthinned plots, and the differences in mortality according to thinning intensity increased over time. Consequently, the growth of DBH and tree volume was lower as stand density increased, but this growth was facilitated with appropriate first and second thinning operations.