• Korean journal of applied entomology
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• v.57 no.3
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• pp.143-149
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• 2018

The black pine bast scale (BPBS), Matsucoccus thunbergianae (Homoptera: Margarodidae), is one of the most serious insect pests of Japanese black pine (Pinus thunbergiana) in Korea. The density of BPBS varies by tree, branch, and location, making it difficult to monitor them. This study investigated to find a monitoring method for distribution and occurrence of BPBS on Japanese black pine using the yellow sticky trap. The density of male BPBS on sticky trap and nymphs from the branch of Japanese black pine was highly correlated in various surveyed sites. The number of male BPBS that attracted to the yellow sticky traps was higher in upper crown than the lower crown of P. thunbergiana but this was not statistically significant. The density of BPBS nymphs increases with the increase of the diameter of the branch, but the differences were not significant from 1 to 2.5 cm. BPBS was highly distributed in bottom-faced branch than the upper-faced branch of P. thunbergiana. Therefore, we suggest, the yellow sticky trap for the monitoring of BPBS and when examining the nymph density in branch, it is recommended that the bottom-faced branch of the 2-2.5 cm diameter branch be examined.

• Journal of Korean Society of Forest Science
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• v.99 no.1
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• pp.62-67
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• 2010

This study was carried out to develop local allometric biomass regression equations and to estimate aboveground biomass of red pine (Pinus densiflora S. et Z.) stands among three regions (Hadong, Hamyang, Sancheong) from the western regions of Gyeongnam province. We selected three natural red pine stands with similar stand ages (about 40-year-old) from each region. The allometric regression equations were significant in all tree components (P<0.05) and the determination of coefficient ($R^2$) ranged 0.87 from 0.99. There was a significant difference (P<0.05) in the biomass of tree components among three regions. The biomass was 173.3 Mg/ha in Hadong, 131.0 Mg/ha in Sancheong, and 66.5 Mg/ha in Hamyang. The proportion of biomass was 70.4-77.1% in stemwood, 10.9-15.2% in branch, 8.9-10.4% in stembark, and 3.1-4.4% in needle. The results indicated that red pine stands in the western Gyeongnam regions showed the significant difference of aboveground biomass which was attributed to site quality and stand density.

• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.285-293
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• 2009

This research had been executed to find out the structure of Magnolia obovata community, a dispersal range and characteristics of scatter investigation, and to prepare management measure of it. In the result of this study, Magnolia obovata was distributed in a native plant community from planting trees of UNESCO Peace Center. The maximum numbers of Magnolia obovata were found in $20{\sim}100m$ from trees of mother. Seed of Magnolia obovata has a characteristics of gravity dispersal. But some individuals was found in 420m from its tree of mother. Seeds of Magnolia obovata has a characteristics of animal dispersal, too. Major species of animal dispersal are Garrulus glandarius, Ciurus vulgaris coreae, and Tamias sibiricus asiaticus in the study site. The importance value between native plants and Magnolia obovata had a negative relation. Because Magnolia obovata is more shade tolerant than other trees. Also, the growth of Magnolia obovata is faster than other trees. And so if the influence of Magnolia obovata reduce, it is necessary to expand native plant community, and to cut Magnolia obovata over 10m of the height and over 10cm of the DBH, for preventing influence of Magnolia obovata.

• Journal of agriculture & life science
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• v.46 no.5
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• pp.1-10
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• 2012

This study analyzed on the characteristics of vegetation structure, species composition and DBH class distribution in order to conservation and effective management for Taxus cuspidata community in Mt. Seorak, Mt. Balwang, Mt. Taebaek, and Mt. Odae. The vegetation in upper, subtree and shrub layer was consist of 11, 22, 33 species in Mt. Seorak, 15, 21, 33 species in Mt. Balwang, 10, 23, 36 species in Mt. Taebaek, and 14, 30, 32 species in Mt. Odae. As a result of importance value at all study sites, T. cuspidata and Abies nephrolepis in upper layer, T. cuspidata, A. nephrolepis and Acer komarovii in subtree layer, and Tripterygium regelii in shrub layer were high, respectively. Species diversity in upper and subtree layer at all study sited were ranged 0.834~1.234 and 1.125~1.329, respectively. According to the DBH class of major three species, T. cuspidata in Mt. Odae site showed a reverse J-shaped curve, which was estimated that T. cuspidata community of this site might be maintained continuously as a stable state.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.284-293
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• 2020

We present a quantitative survey of the carbon storage and absorption capacity of tree species in the vegetation conservation and ecological restoration areas of Bulamsan urban nature park in Nowon-gu, Seoul. The density of the sawtooth oak (Quercus acutissima) community in the ecological conservation area is approximately 30 individuals/225 ㎡, while a further 20 species, such as Japanese snowbell (Styrax obassia), galcham oak (Quercus aliena), Asian Sweetleaf (Symplocos chinensis f. pilosa), East Asian ash (Fraxinus rhynchophylla), and Korean rhododendron (Rhododendron mucronulatum) are sparsely distributed. In contrast, the ecological restoration sites typically comprised Mongolian oak (Quercus mongolica), jolcham oak (Quercus serrata), and East Asian ash (Fraxinus rhynchophylla) plantations, with planting densities of 8.3, 7.7, and 14.3 individuals/25 ㎡ , respectively. Approximately 10 species, including Amur maple (Acer tataricum subsp. ginnala), Korean mountain ash (Sorbus alnifolia), Japanese spice bush (Lindera obtusiloba), and Korean rhododendron (Rhododendron mucronulatum) were identified in the ecologically restored area. The total amounts of carbon stored by the trees in the vegetation conservation and ecological restoration sites are 250.77 and 19.3 t C ha-1, respectively, and the total annual carbon uptakes are 10.28 and 2.33 t C ha-1 yr-1, respectively. The survey results are expected to provide important basic data for monitoring the carbon absorption capacity and carbon balance of green areas in the city.

• 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.95 no.1
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• pp.102-112
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• 2006

The change of species composition and stand structure along altitudinal gradients in different aged stands was studied in five natural stands located each at 400 m, 800 m, 1,000 m, and two at 1,300 m above sea level (asl) in the western part of Mt. Chiri in Korea. Trees larger than 2.5 cm DBH were inventoried in 3 to 8 $20m{\times}20m$ quadrats in each study site. Stand ages were estimated based on the ages of Pinus densiflora Siebold & Zucc. and Abies koreana Wilson, and used to analyze the changes in species composition and stand structure including diameter and height distributions. Species composition was changed along altitudinal gradients as P. densiflora dominated stands at 400 m asl while A. koreana dominated stands at 1,300 m asl. Major species of Quercus also changed along altitudinal gradients as Quercus variabilis Blume at 400 m asl, Quercus serrata Thunb. ex Murray at 800 m asl, and Quercus mongolica Fisch. ex Ledeb. at higher than 1,000 m asl. The diameter distribution did not show significant differences among stands of different altitudes. However, the height distributions of upper crown layers were significantly different among stands at below and above 1,000 m as) (P < 0.0001). Trees taller than 20 m rarely appeared in stands over 1,000 m asl. P. densiflora dominant stands at 400 m asl developed two clumped age groups as one in 30-40 ages and the other around 70 years old. Q. serrata dominant stands at 800 m asl, Q. mongolica dominant stands at 1,300 m asl and A. koreana dominant stands at 1,300 m asl were estimated to be around 30, 70, and over 140 years old after major disturbances, respectively. The diameter distribution with age structure indicated that P. densiflora at 1,300 m asl might be replaced by Q. mongolica, and Q. mongolica might be replaced by A. koreana and Pinus koraiensis later. A. koreana dominant stand seemed to stay its dominance quite long if the large disturbance would be absent.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.492-503
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• 2020

This study was conducted to analyze stem decay in Quercus mongolica and Quercus variabilis in Korea. To ensure even allocation, a total of 5,005 sample trees (2,504 Q. mongolica and 2,501 Q. variabilis) were cut and collected in five regions and 27 subregions. The trees were then examined for stump decay and assigned to four classes based on the degree of scar, tissue decay and decolorization, splitting, and tree hollowing. The results show that the decay rate of Q. mongolica was 66.1%, at least twice as high as that of Q. variabilis, which was rated at 35% (χ2 = 631.15, p < 0.001). The comparison among regions indicated that the highest ratio of Q. mongolica occurs in the Central Regional Forest Service zone (76.5%), followed by the Northern zone (74.8%) and Eastern zone (65.7%). In contrast, the greatest proportion of Q. variabilis is found in the Northern Regional Forest Service zone (38.6%), followed by the Southern (32.9%) and Eastern (37.8%) zones. A statistically significant difference was seen among the five zones (p < 0.05, p < 0.001). There was also a clear tendency for the proportions for the two species to increase with a rise in the DBH. With respect to age, however, a statistically significant difference was found (p < 0.01, p < 0.05) only in Q. mongolica, whose rate increased with the increase in age. Our results show that as the DBH and age increases, the conditions of tissue decay and decolorization are manifested in Q. mongolica, whereas scars are common in Q. variabilis.

• Journal of Korean Society of Forest Science
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• v.74 no.1
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• pp.67-81
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• 1986

To investigate the stand structure of the stocked broad-leaved forests in Korea, 1,000 plots, allocated by systematic sampling method, were interpreted on the aerial photographs accompanied with ground survey. Total area of the stocked broad-leaved forests except Jeju island was 818,286ha and the percentage to total forest area was 12.7%. Total stock volume of the stocked broad-leaved forests was $38,890,779m^3$ and the percentage to total stocked forest volume was 27.4%. Mean number of trees per ha was 947 trees/ha, basal area was $11.17m^3/ha$, DBH was 11.30cm, tree height was 7.65m, stock volume was $44.96m^3/ha$, and current annual volume increment was $3.64m^3/ha$ in total land. The 64.7, 79.8 and 52.7 percent of the stocked broad-leaved forest area were distributed at elevations of 300-900m, in slope degree of above 25, and in northern aspect, respectively. Standfactors were apt to get better with the increase of distance from the car road way and the village, and with the increase of elevation belt.

• Korean Journal of Environment and Ecology
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• v.37 no.3
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• pp.182-191
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• 2023

This study was carried out to identify the distribution and growth characteristics and evaluate the conservation status of the Michelia compressa Maxim., a rare and endangered wild plant II, in the habitats in Korea. A total of 314 individuals were found in the natural habitats of Heuksan Island and Jeju Island and were divided into four populations. About 45.9% (144 individuals) were distributed in the range of 401m~500m above sea level. The average height of trees was 2.7(±4.8)m, the diameter at breast height was 12.6(±13.9)cm, and the number of branches was 1.0(±0.5) on average. 54.3% of the sapling individuals of M. compressa were distributed within a radius of 30 m from the mother tree, 25.8% were distributed between 31 m through 40 m, and most (90.1%) were distributed within a radius of 60 m. The fact that sapling individuals of M. compressa are not identified even around some mature individuals and appear only in extremely limited areas is estimated to be closely related to the growth conditions as well as the environment of the natural habitats. The dispersal of M. compressa is presumed to be related to the birds and natural seedlings because water puddles, a resting place for birds beyond the range of natural seedlings, characterize its habitats. The IUCN Red List evaluation criteria at the regional and national level of M. compressa corresponds to the Critically Endangered category, and the domestic population under the category of "CR B2ab(v); C2a(i); D."