• Journal of Climate Change Research
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• v.6 no.4
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• pp.357-366
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• 2015

This study was conducted to estimate carbon stocks of Quercus serrata with drawing volume of trees in each tree height and DBH applying the suitable stem taper equation and tree specific carbon emission factors, using collected growth data from all over the country. Information on distribution area, tree number per hectare, tree volume and volume stocks were obtained from the $5^{th}$ National Forest Inventory (2006~2010), and method provided in IPCC GPG was applied to estimate carbon storage and removals. Performance in predicting stem diameter at a specific point along a stem in Quercus serrata by applying Kozak's model,$d=a_1DBH^{a_2}a_3^{DBH}X^{b_1Z^2+b_2ln(Z+0.001)+b_3{\sqrt{Z}}+b_4e^Z+b_5({\frac{DBH}{H}})}$, which is well known equation in stem taper estimation, was evaluated with validations statistics, Fitness Index, Bias and Standard Error of Bias. Consequently, Kozak's model turned out to be suitable in all validations statistics. Stem volume tables of Quercus serrata were derived by applying Kozak's model and carbon stock tables in each tree height and DBH were developed with country-specific carbon emission factors ($WD=0.65t/m^3$, BEF=1.55, R=0.43) of Quercus serrata. As a result of carbon stock analysis by age class in Quercus serrata, carbon stocks of IV age class (11,358 ha, 36.5%) and V age class (10,432; 33.5%) which take up the largest area in distribution of age class were 957,000 tC and 1,312,000 tC. Total carbon stocks of Quercus serrata were 3,191,000 tC which is 3% compared with total percentage of broad-leaved forest and carbon sequestration per hectare(ha) was 3.8 tC/ha/yr, $13.9tCO_2/ha/yr$, respectively.

• Journal of Forest and Environmental Science
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• v.36 no.1
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• pp.1-6
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• 2020

This study was conducted to investigate the effect of different pre-sowing treatments of seeds on germination and growth performance of native threatened tree species Quercus gomeziana A. Camus at the nursery of Chittagong University, Bangladesh. Furthermore, seedling growth attributes under different doses of fertilizer (urea) was also experimented to find the best dose of fertilizer on this tree species at the nursery stage for better field level growth. Seeds were placed to six pre-sowing treatments e.g. control (PT₀), treated with sand paper rubbing (PT₁), nicking (PT₂), seeds immersed in cold water for 48 hours (PT₃), seeds immersed in cold water for 7 days (PT₄) and seeds sown at propagator house with increased temperature (PT₅). It was found from the study that germination was started earlier (at 31 days) in treatments sand paper rubbing (PT₁) and nicking (PT₂). The highest germination percentage (93%) was in PT₁ followed by 86% in seeds immersed in cold water for 7 days (PT₄) and 80% in PT₀ (control). Germination percentage was observed least (63%) in PT₂ even though germination started earlier. For fertilizer dose experiment to seedlings at the nursery level, treatment FT₁: 100 kg/ha (0.33679 g urea/pot/seedling) comparing with other treatments FT₀: 0 kg/ha (Control), FT₂: 200 kg/ha (0.67358 g urea/pot/seedling), FT₃: 300 kg/ha (1.01037 g urea/pot/seedling) showed better performance in case of collar diameter (6.74 mm), number of leaves, shoot dry weight (19.74), total dry weight (28.16 g), total fresh weight (67.96 g), volume index (3904.82), sturdiness (127.69). Finally, it can be concluded that Quercus gomeziana seedlings revealed better performances under the treatment FT₁ in growth and biomass production. Findings of this study will be helpful to take decision on organic fertilizer dose application to seedlings of Q. gomeziana for large scale plantation and conservation of this species.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.431-440
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• 2005

Location, height and clear-length of individual tree can be measured directly by LiDAR Remote Sensing, and dbh(diameter at breast height) can be estimated indirectly by tree height measured by LiDAR. In addition, stand volume and stand biomass are computed from estimated growth factors. In this study, each estimated growth factor was compared to the field measurements to validate accuracy. The coefficient of determination of total tree heights was 0.66 for total trees, 0.68 for Pinus koraiensis, 0.66 for Larix leptolepis and 0.60 for Quercus spp. The coefficient of determination of clear-length was 0.79 for total trees, 0.73 for Pinus koraiensis, 0.79 for Larix leptolepis, 0.68 for Quercus spp. The coefficient of determination of dbh predicted was 0.73 for Pinus koraiensis, 0.73 for Larix leptolepis and 0.85 for Quercus spp. Moreover The coefficient of determination of basal area was 0.82 for Pinus koraiensis, 0.92 for Larix leptolepis and 0.95 for Quercus spp. Biomass per ha computed by growth factor using LiDAR was 40,306 dm/ha for Pinus koraiensis, 94,150 tdm/ha for Larix leptolepis and 94,481 tdm/ha for Quercus spp. by species.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.482-489
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• 2022

This study aimed to determine the optimal planting density of Fraxinus rhynchophylla assessed from the early growth performance at various planting densities over the 7-year period after planting. The study site was in Pyeongchang County, South Korea, and seedlings of 2-year-old (bare-root seedlings) F. rhynchophylla were planted at four densities (3,000, 5,000, 7,000, and 10,000 trees ha^-1) in March 2015. The survival rate, root-collar diameter (RCD), and height (H) were measured from 2015 to 2021, and the H/D (H/RCD) ratio and stem volume were calculated. The survival rate (84-97%) and H/D ratio (54.5-59.2%) were not affected by the planting density during the study period, but the RCD, H, and stem volume were significantly higher for 7,000 trees ha^-1 than for other planting densities. Especially, the stem volume (cm³ tree^-1) at 7 years after planting was highest for 7,000 trees ha^-1 (1,356.1), followed by 10,000 trees ha^-1 (958.6), 5,000 trees ha^-1 (773.0), and 3,000 trees ha^-1 (579.5). As the planting density increased, F. rhynchophylla seedlings showed initial rapid growth due to light competition, but relatively low growth at excessive planting densities. In the future, use of a suitable planting density considering planting costs should provide outstanding growth performance of F. rhynchophylla on plantations.

• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.51-61
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• 2002

This study was conducted to investigate and compare species composition, stand structure, and growth pattern for two different sites in which silvopastoral system has been taking place. One site was the pasture area where a number of trees were removed and grasses were planted for cattle grazing, and the other site was the deciduous forest that has been established by ecological succession. The results were as follows: 1. Nine tree species were present equally in the pasture area and the deciduous forest. Of these species, seven tree species were growing in common for two sites. However, the species composition, including density and frequency, was varied by sites. 2. The number of stems per hectare in the pasture area was 71, and that in the deciduous forest was 1,433, having shown the big difference. It is estimated that, considering the growth rate, better grown trees were remained at the time of harvesting in 1996. 3. The growth of diameter, height, and basal area in the pasture area was superior to that in the nearby deciduous forest. In spite of higher values of diameter and height, the timber volume of pasture area per unit area was less than 15% of that in the deciduous forest. 4. Providing sufficient growing space, the pasture area supported higher values of diameter and height. The wider growing space also had influence on the expansion of crown of trees by the result of deliquescent growth pattern. From this point of view, more research would be needed to establish appropriate number of trees for silvopastoral system.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.62-69
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• 2011

Six commonly used non-linear growth functions were fitted to individual tree height-dbh data of eight major tree species measured by the $5^{th}$ National Forest Inventory in Chungcheong province. A total of 2,681 trees were collected from permanent sample plots across Chungcheong province. The available data for each species were randomly splitted into two sets: the majority (90%) was used to estimate model parameters and the remaining data (10%) were reserved to validate the models. The performance of the models was compared and evaluated by $R^2$, RMSE, mean difference (MD), absolute mean difference (AMD) and mean difference(MD) for diameter classes. The combined data (100%) were used for final model fitting. The results showed that these six sigmoidal models were able to capture the height-diameter relationships and fit the data equally well, but produced different asymptote estimates. Sigmoidal growth models such as Chapman-Richards, Weibull functions provided the most satisfactory height predictions. The effect of model performance on stem volume estimation was also investigated. Tree volumes of different species were computed by the Forest Resources Evaluation and Prediction Program using observed range of diameter and the predicted tree total height from the six models. For trees with diameter less than 30 cm, the six height-dbh models produced very similar results for all species, while more differentiation among the models was observed for large-sized trees.

• Journal of Environmental Science International
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• v.19 no.2
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• pp.229-236
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• 2010

As air pollution has emerged as one of the most pressing urban environmental concerns, many studies have investigated the influence of air pollutants(ex: $O^3$, $NO^2$, $SO^2$, Acid rain, etc.) on roadside trees and urban grove. In Korea, population density started to increase since the industrialization. Since dense population aggravates our living conditions, it's very important for us to preserve and keep a lively and refreshing nature in order to live with green nature in harmony under the current artificial environment-dominating world. In metropolitan cities, the production of pollutants increases in proportion to population growth. The vehicle exhaust gas and air pollutants from cooling and heating systems have been the major causes of acid rain. Furthermore, tire particles which are naturally produced by tire wearing on roads and other toxic substances in exhaust gas have caused a problem in human health directly and indirectly. In fact, a lot of studies have analyzed air pollution, roadside trees and plants in Korea. However, they are mostly limited to covering the influence of air pollution on the growth of plants. No paper has clearly explained why air pollution-resistant or-vulnerable species has shown different reactions yet. Even though a lot of urban roadside trees have died or stopped to grow from time to time, this kind of problem has not been properly examined. This paper is aimed to comparatively analyze physio-ecological characteristic such as photosynthesis, chlorophyll contents, soil volume water figure out their relationship with environmental factors against the expanding roadside trees in Cheong-ju, and provide basic data for management of roadside trees and elaboration of urban environment preservation policies.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.6
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• pp.525-532
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• 2001

In this paper, physical properties and electrical characteristics of linear low density polyethylene(LLDPE) films blended with ethylene vinyl acetate(EVA), containing polar groups within it, were investigated to improve defects of polyethylene(PE) such like space charge accumulation and tree growth. Blending method changes super-structure of LLDPE, having a great influence on electrical characteristics. For analysis of physical properties, FTIR, XRD and DSC methods were executed, and for electrical characteristics, volume resistivity and dielectric strength were measured with the varying temperature. From the results, it is confirmed that bled specimens tend to be safe to varying temperature, and specially of 70:30 and 50:50 have a good performance.

• Journal of Korean Society of Forest Science
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• v.77 no.4
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• pp.382-388
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• 1988

Improvement of productivity by forest tree breeding work in Korea was estimated for a few important tree species. Progenies of 17 plus trees of red pine (Pines densiflora) outgrew by 57 percentage compared with progenies of unselected trees at age 15. If best three families are selected among the 17, more than double in volume grow-th is expected. The hybrid Pinus rigida ${\times}$ P. taeda showed more than double volume growth compare to P. rigida at a southern plantation at age 15. However, the superiority of the hybrid decreased at northern plantations, mainly because of low coldhardiness of the hybrid. At a northern plantation, the hybrid grew less than the P. rigida on upper hill, while the hybrid grew much better than the P. rigida on flat area. Another hybrid Populus alba ${\times}$ P. glandulosa grew faster than both parents by two to two and half times according to planting sites at age 10. Introduction of Pinus rigida also showed increased volume growth. Volume increase by selection of best five provenances among 45 at age 12 was estimated as 53 percent compare to progenies of plus trees in Korea, Additional 19 percent of volume increase was expected by selection of the best families within the best provenances. Annual production of chestnuts reached about 70,000 M/T by planting resistant clones to chestnut gall wasp (Dryocosmus kuriphilus), which killed almost all susceptible trees. Although polyploid trees and mutants have been produced by colchicine treatments in over 10 tree species, none of them is economically important Remarkable improvement of productivity is expected by biotechnology in future through selection, hybridization, introduction of foreign genes at cell, cell organelle and gene level, and gene transformation. At present, mass propagation of superior planting materials by tissue culture will increase the productivity.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.390-399
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• 2020

We investigated the effect of seedling age and planting density on early growth performance of Zelkova serrata trees. Containerized Z. serrata seedlings, 1-year-old and 2-year-old, were planted according to two different planting densities (3,000 and 5,000 trees ha-1) at the end of March, 2017. Three plots were established for each treatment (2 seedling ages × 2 planting densities). We calculated the survival rate (%) of out-planted seedlings as well as the stem volume based on the root collar diameter (RCD) and height (H) in September of each year, from 2017 to 2019. Seedling age and planting density did not affect survival rate of the out-planted trees. Planting density did not affect height of the trees, whereas the treatment significantly affected RCD and the H/D ratio for 2-year-old seedlings in 2019. The stem volume per tree was highest in the plot of 2-year-old seedlings at 5,000 trees ha-1 and lowest in the 1-year-old seedlings at 3,000 trees ha-1. In addition, the tree height in both 1-year-old and 2-year-old Z. serrata trees was greater in the 5,000 trees ha-1 plot than in the 3,000 trees ha-1 plot. There was no interactive effect between seedling age and planting density on stem volume; however, as seedling age and planting density increased, stem volume of Z. serrata trees increased. The values for stem volume per hectare are 85%, 68%, and 300% higher in 1-year-old 5,000 trees ha-1, 2-year-old 3,000 trees ha-1, and 2-year-old 5,000 trees ha-1 plots, respectively, compared to the values in 1-year-old 3,000 trees ha-1. This result shows that high planting density (close planting) affects tree growth differently based on seedling age, and suggests that the planting density of 5,000 trees ha-1 is suitable for 2-year-old seedlings to improve early growth field performance.