• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.124-132
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• 2001

This study was conducted to reveal the relationship between physiological characteristics and growth by family for open-pollinated progeny stand of Korean white pine in Gapyung site. Average growth performance of total 25 families for 18 years old progeny stand in this study site showed 5.9m in mean height, 8.9cm in mean DBH, $12.0m^2$ in basal area per hectare and $46.5m^3$ in volume per hectare, respectively. By the analysis result of growth performance for all 25 families, family No. 20 showed the most excellent growth and middle in family No. 10. On the other hand, family No. 3 represented the worst growth among the 25 families. The change of seasonal photosynthesis rate by increasing luminous intensity was the same tendency as the growth pattern of all 25 families and showed the same results in all four seasons. In the seasonal analysis, the photosynthesis rate was increased as the season has changed from winter to summer. Chlorophyll contents was also increased from winter to summer. Especially, family No. 20 which is the best in growth performance has more chlorophyll contents than the others. In addition, family No. 20 was also better than other families in the weight of assimilation tissue(g), length of needle(cm), width of needle(cm), and number of Stoma. However, in water utilization rate, family No. 3 which is the worst in the growth performance showed the best result that is reverse tendency compared with the photosynthesis rate. The changes of water utilization rate represented to be increased as the season has changed from winter to summer.

• Korean Journal of Plant Resources
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• v.34 no.2
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• pp.144-155
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• 2021

This study was conducted to analyze community structure and species composition of Abies koreana forest. Field survey was carried out from June, 2019 to 2020, September. 121 plots (20×20 m) were set up, 5 herb layer plots (3×3 m) were constructed for each plot, and there, Diameter at Breast Height(DBH), height, environmental factor were measured. It was analyzed that water stress did not have a significant effect on the factors affecting the growth of A. koreana in Mt. Halla-san, and in the case of Mt. Deokyu-san, the more forest stands located at the ridge, the higher the tree density. It was found that the factors affecting the distribution of Abies koreana were not consistent according to the environment of study site.

• Journal of Forest and Environmental Science
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• v.35 no.2
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• pp.69-77
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• 2019

Pterocarpus erinaceus is a multipurpose tree species indigenous to semi-arid and Guinean-savanna woodlands of Africa. Natural regeneration on the savanna is being hampered by higher fire frequencies and other land use changes. Simultaneously, demand for timber from the species on the international market is on the rise, raising conservation concerns. To ensure sustainability, good quality seeds, sources of which have not received much research focus, are needed for afforestation. This study investigated how seed quality, germinability and initial seedling growth of P. erinaceus might be influenced by land-use type, mother tree size as well as source and timing of fruit harvest, using both correlational and experimental approaches. The results showed that up to 94.6% of all harvested fruits contained seeds, with no differences found between fruits harvested from cultivated and non-cultivated lands. Percentage of (sound) unblemished seeds was found to be higher for fruits harvested early March (47.3%) than fruits from late April (39.5%). Percentage sound seeds was 41.4% for dispersed fruits (i.e. detached fruits picked from under mother trees) which was not found to differ from undispersed fruits (i.e. fruits harvested while still attached to mother trees) at 45.5%. Also, the influence of fruit harvest time was not found to be different for dispersed and undispersed fruits. Correlations between seed set (proportion of fruits containing seeds) and mother tree size (both tree height and DBH) were found to be very low and non-significant for both dispersed and undispersed fruits. Across mother trees, mean emergence percent was 79.7%, and mean seedling height at three weeks following emergence was 5.32 cm. Both emergence percentage and seedling height were not found to differ among mother trees, but seeds from dispersed fruits had a higher emergence percent (85%) than seeds from undispersed fruits (74%). Implications of findings are discussed.

• Korean Journal of Environment and Ecology
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• v.35 no.4
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• pp.408-423
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• 2021

We established and monitored survey sites in seven regions of Mt. Jiri to investigate population decline and change of the Korean fir (Abies koreana) over a ten-year period from 2009 to 2018. With the exception of one site (Seseok), the six remaining ones all showed a four-layer stratification structure. The importance value of Korean firs in all of the survey areas decreased significantly by 28.5%, from 55.7% in 2009 to 39.8% in 2018. The average population of objects with a diameter at breast height (DBH) of 5cm or more in all survey sites was 711 objects/ha in 2018, and the cumulative death rate from 2009 to 2018 was 10.8%. Among the death types, DS (dead standing) was the most dominant, comprising 82.4% of the total survey area. However, in Banyabong 1, which had a high gradient of 35°, the death types other than DS accounted for 44.2%. We estimate that A. koreana can maintain a stable population as its distribution type for each diameter class in the Saeseokpyeongjeon site showed a reverse-J shape. The average annual ring growth in all survey sites was 1.09 mm/year, with the most abundant growth observed in the Seseokpyeongjeon site, which was formed mainly by a subtree layer. The growth ring survey showed the estimated average age of A. koreana population in the Byeoksoryeong and Banyabong 1 sites to be 102 and 91 years, respectively, a general downward trend of vitality since 2013.

• Korean Journal of Environment and Ecology
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• v.35 no.4
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• pp.398-407
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• 2021

This study intended to identify causes of poor tree vigor in the Hanbando coastal forest by investigating its geographical environment, climate condition, soil physicochemical characteristics, and growth condition of Pinus thunbergii. It divided the forest into an area with poor tree vigor or dead standing trees and a control area with good tree vigor and examined them separately. The survey showed that stand density was significantly higher in the area with poor tree vigor. In contrast, the crown width in the area with good tree vigor was wider. The number of dead standing trees and the stand density showed a negative correlation. The stand density and diameter at breast height (DBH), tree height, crown height, and crown width also showed a negative correlation. The result indicated that, as the tree's stand density increases, the crowns of individual trees overlapped and the lower branches died. Then crown height and crown width decreased, and the number of leaves and photosynthesis was reduced, leading to lower tree height and weaker growth of breast diameter. As a result, tree vigor weakened, and combined with environmental pressures from the lack of moisture and nutrients in coastal soil and salty wind, P. thunbergii in coastal areas is expected to die massively. Although the causes of dead standing trees and poor tree vigor of P. thunbergii in the Hanbando coastal forest are complicated, poor management of adequate tree density in response to the growth of P. thunbergii is the primary cause. The secondary cause is external environmental pressures, including unfavorable soil conditions and salty and strong wind that obstruct the growth of P. thunbergii.

• Korean Journal of Environment and Ecology
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• v.35 no.6
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• pp.632-643
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• 2021

The objective of this study was to examine vegetation community structure and distribution of Fraxinus chiisanensis in Mt.Minjuji of Chungcheongbuk-do by setting up and surveying 8 plots (400 m² each). Mean Importance Value (MIV) of Fraxinus chiisanensis in 8 plots was 35.19% in average (ranging from 26.07~42.74%). Since it is the dominant species in all plots, it is expected to maintain the present vegetation structure. The analysis of the DBH (diameter at breast height) showed that the diameter of Fraxinus chiisanensis in Mt.Minjuji ranges from 2 to 43cm. The majority of Fraxinus chiisanensis is expected to maintain current state unless disturbance or rapid environmental change occurs. The Species Diversity (H') was 0.8498~1.0261, Evenness (J') was 0.8160~0.9256, Dominance Index (D) was 0.0789~0.1840, Maximum Diversity (H'max) was 1.0414~1.2041. The analysis of annual ring and radial growth showed that the average age of Fraxinus chiisanensis in Mt.Minjuji was 29.1years(ranging from 22~58years). The average annual radial growth of Fraxinus chiisanensis was the highest in community G with 5.84mm and the lowest in community B with 2.80mm. The similarity index analysis revealed that the similarity index between community B and E, C and F, H was the highest with 69.0%, and the similarity index between community E and F was the lowest with 29.6%. Both the area of Fraxinus chiisanensis community of Mt.Minjuji and its population size are very small. Therefore, this area needs to be designated as Forest Genetic Resource Reserve.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.538-547
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• 2022

In this study, the population and community structure of Berchemia berchemiaefolia stands located at Mt. Naeyon (Gyeongbuk, Korea) were quantified, and multivariate analysis was done to determine the correlations between vegetation group types and environmental factors and to have reference data for the conservation and restoration of this species. In total, there were 164 B. berchemiaefolia trees in Mt. Naeyon. The average DBH of the trees was 24.5 cm, forming a normal distribution. It rarely appeared in an understory vegetation height of 3 m. About37.1% of the trees were branched. B. berchemiaefolia stands were classified into two groups: B. berchemiaefolia-Quercus serrata community and B. berchemiaefolia-Carpinus laxiflora community. Canopy gap, organic matter, exchangeable Ca, and cation exchange capacity were the major site characteristics affecting the distribution pattern of the stands. Currently, B. berchemiaefolia trees dominate in Mt. Naeyon, but depending on different habitat positions, the species was in a natural successional stage to C. laxiflora or C. cordata, which is a shade-tolerant species.

• Journal of Korean Society of Forest Science
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• v.112 no.4
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• pp.405-416
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• 2023

In this study, the sustainability of Abies nephrolepis in the presence of Tripterygium regelii was analyzed. To accomplish this, a field survey of140 stands was conducted. Based on the presence or absence of T. regelii, as well as the layer in which it was present (where appropriate), the type of T. regelii presence wasclassified as follows: TP type, indicating the presence of T. regelii in the tree and sub-tree layers; SP type, indicating its presence in the shrub layer; and A type, indicatingits absence from all layers. The indicator species analysis revealed T. regelii to be an indicator species of the TP type and SP type. The MRPP test was used to examine the differences among the types. Moreover, the seedling and DBH class analysis indicated there to be a difficulty in terms of the status competition, as the number of young trees generated by A. nephrolepis was the lowest in the TP type. The findings of this study enhanced our understanding of the vegetation structure of A. nephrolepis, thereby contributing to efforts concerningits conservation and management.

• Journal of Korean Society of Forest Science
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• v.113 no.2
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• pp.143-152
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• 2024

This study was conducted to evaluate the growth and nutrient dynamics in response to fertilization of four tree species (LT: Liriodendron tulipifera L.; PY: Prunus yedoensis Matsumura; QA: Quercus acutissima Ca rruth; a nd PT: Pinus thunbergii Parl.) planted in a fire-disturbed urban forest in Bongdaesan (Mt.), Ulsan Metropolitan Area, South Korea. The trees were planted in 2009, and compound fertilizers (N₆P₄K₁) were applied in April 2013 and March 2014. Tree growth, soil, and foliage nutrients were examined from March 2013 to October 2016. The regression coefficients for the increment of the diameter at breast height (DBH) significantly differed between the fertilized and unfertilized plots, suggesting the significant effects of fertilization. By contrast, fertilization did not affect the coefficients for height increments. Regarding soil nutrient contents, organic carbon and total nitrogen concentrations were lower in the fertilized plots than in the unfertilized plots, whereas available phosphorus, exchangeable calcium, and magnesium concentrations were higher in the fertilized plots than in the unfertilized plots. In foliage, nitrogen and phosphorus concentrations were higher in the fertilized plots than in the unfertilized plots, whereas potassium, calcium, and magnesium concentrations were not affected by fertilization. Nutrient concentration of foliage among the tree species were higher in LT and PY than in QA and PT. These results suggest that fertilizers may be used to enhance soil fertility and the growth and nutrient status of tree species planted in a fire-disturbed urban forest.

• Journal of Korean Society of Forest Science
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• v.113 no.2
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• pp.187-197
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• 2024

In this study, we aimed to identify the factors influencing post-fire mortality in Korean red pine (Pinus densiflora) using Cox's proportional hazards model and analyze the impact of these factors. We monitored the mortality rate of fire-damaged pine trees for seven years after a forest fire. Our survival analysis revealed that the risk of mortality increased with higher values of the delta normalized difference vegetation index (dNDVI), delat normalized burn ratio (dNBR), bark scorch index (BSI), bark scorch height (BSH) and slope. Conversely, the risk of mortality decreased with higher elevation, greater diameter at breast height (DBH), and higher value of delta moisture stress index (dMSI) (p < 0.01). Verification of the proportional hazards assumption for each variable showed that all factors, except slope aspect, were suitable for the model and significantly influenced fire occurrence. Among the variables, BSI caused the greatest change in the survival curves (p < 0.0001). The environmental change factors determined through remote sensing also significantly influenced the survival rates (p < 0.0001). These results will be useful in establishing restoration plans considering the potential mortality risk of Korean red pine after a forest fire.