• Proceedings of the Korean Society of Computational and Applied Mathematics Conference
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• 2003.09a
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• pp.16.1-16
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• 2003

A subset S of vertices of a graph G is independent if no two vertices of S are adjacent by an edge in G. Also we say that S is maximal independent if it is contained In no larger independent set in G. A planted plane tree is a tree that is embedded in the plane and rooted at an end-vertex. A (k＋1) -valent tree is a planted plane tree in which each vertex has degree one or (k＋1). We classify maximal independent sets of (k＋1) -valent trees into two groups, namely, type A and type B maximal independent sets and consider specific independent sets of these trees. We study relations among these three types of independent sets. Using the relations, we count the number of all maximal independent sets of (k＋1) -valent trees with n vertices of degree (k＋1).

• Journal of Environmental Science International
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• v.21 no.11
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• pp.1307-1320
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• 2012

The purpose of this paper is to provide information on planting construction for healthy plant growth. To achieve this purpose, this study analyzed the planting type, planting density, withering rate, soil characteristics, and cambium electrical resistance (CER) of withered trees in an apartment complex with a high withering rate. The major plant groups examined consisted of native broad-leaved tree species (39.3%), native narrow-leaved tree species (24.2%), and native broad-leaved - exotic narrow-leaved tree species (16.4%). The planting density of the green area, where trees were planted from 0.0 to 0.3 trees per unit area, was measured as 98.4%. Withered trees were found in 19 of the 20 planted species, and the withering rate was 41.8% (610 withered/1,461 planted). Withering rates for tree species were measured as follows: Sophora japonica and Salix babylonica (100.0%), Magmolia denudata (84.3%), Lindera obtusiloba (74.7%), cornus kousa (69.3%), acer triflorum (69.2%), diospyros kaki (66.7%), Prunus yedoensis (62.8%), Acer palmatum (52.6%), Prunus armeniaca (51.1%), Chaenomeles sinensis (43.7%), Ginkgo biloba (40.9%), Zelkova serrata (31.0%), Cornus officinalis (28.6%), Taxus cuspidata (25.6%), Pinus densiflora (21.4%), Pinus parviflora (15.2%), Pinus strobus (14.6%), and Abies holophylla (10.3%). Soil chemical analyses for 18 samples revealed that as the withering rate increased, the following occurred: (a) the ratio of silt and clay in soil increased; (b) the soil pH, organic matter rate, nitrogen, available phosphorus, and cation exchange capacity (CEC) in samples were graded as "inadequate," based on the plant grading evaluation; and (c) the NaCl and cation exchange capacity were evaluated as "somewhat satisfactory." The measurement of CER for withering rate shows electrical resistance for higher withering rate are higher, which could predict that a tree will not grow well.

• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.87-99
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• 2017

The first purpose of this study is the verification of hypothesis on Abies holophylla planted as a guardian for Japanese. Second, the purpose of this study is on Abies holophylla planted in the historic sites for anti-Japan fighter. Japan planted Abies holophylla to honor the god of Suwataisha that took care of the Jingu-Kogo's Conquest of Samhan(Three Kingdoms). The fact that Abies holophylla was planted in the historic sites for anti-Japan fighter such as General Gwon Yul, Yi Sun-Shin was investigated. The hypothesis that Abies holophylla was planted as a guardian for Japanese was verified through survey on the pictures of Abies holophylla in Japanese temple, public sites, company of nursing the saplings, commemorative tree of governor and the judgment of Abies holophylla damage incident. Further studies should focus on the intention of planting Abies holophylla by Japan. Researcher should discuss Abies holophylla planted in the historic sites for anti-Japan fighter because old big trees will be respected.

• Korean Journal of Environment and Ecology
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• v.36 no.5
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• pp.496-506
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• 2022

The growth of trees planted through transplantation rapidly decreases immediately after planting due to extreme disturbances such as root cutting and crown damage. Although the growth rate is recovered as time elapses, the time required to restore the original growth varies by species. Therefore, it is necessary to set an appropriate tree management period for survival after transplantation by analyzing each species' annual growth change. In this study, we analyzed the growth amount of deciduous broad-leaf species planted in the area where the riparian ecological belt was formed and proposed the management period based on the results. Slowed growth immediately after planting is a common phenomenon due to root cutting and pruning, the pre-works performed to increase tree survival rate during the transplantation process. Afterward, the original growth rate is recovered as time passes, but the time required may vary depending on the species and planting environment. Most of the trees showed a rapid decrease in growth immediately after transplantation. After that, although it is different for each species, most of them showed a gradual recovery from 2 years onwards. The analysis of the growth rate by tree species confirmed that it took 2 to 4 years, depending on the tree species, to recover the growth level before transplantation after a rapid decrease in growth immediately after transplantation. The results suggest that improving the defect rate of planted trees is necessary to meet the project objectives: ecological restoration and pollutant reduction. It requires setting a tree management period of at least two years and creating an appropriate base environment.

• Journal of Forest and Environmental Science
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• v.25 no.1
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• pp.35-41
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• 2009

Agroforestry combines agriculture and forestry technologies to create more integrated, diverse, productive, profitable, healthy and sustainable land-use systems. This study was performed in three union of Chhagalnaiya Upazila (Sub-district; administrative entity) under Feni district, Southern Bangladesh with a view to identify the tree resources, utilization pattern and economic return of major fruit and timber tree species. Information collected from a total of 45 households ranging from marginal, small, medium and large categories. Number of plant species increased with the increase of homestead area. A total of 39 plant species were recorded from the homegarden, of which 23 were fruit and 16 were timber tree species. Considerable number of vegetables was also planted under the shade of the homestead trees. The investment analysis showed that average benefit-cost ratios were greater than one, net present values were positive and internal rate of returns were more than 10%. Long term investment on horticulture and timber tree species is highly profitable if species like Swietenia mahagoni and Tectona grandis, Spondias pinnata, Syzygium cumini and Areca catechu were planted.

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.279-291
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• 2015

This study analyzed the growth characteristics of multi-layer planted trees through their growth analysis and attempted to present a management strategy. The subject of research is the Citizen's Forest Area of Seoul Forest Park located in Seoul City. Field surveys were conducted three times over eight years from 2005 when the Seoul Forest Park was created through 2013. Labels were attached to all trees in the target area, and their species, height and DBH were investigated. To identify the growth differences by trees in each area, a detailed tree location map was drawn up for use in the analysis. To check soil health, soil organic matter, soil pH and soil microbial activities were analyzed. It turned out that the growth of the multi-layer planted trees in the target area of research was higher than that of the trees in existing urban parks, and that it was similar to that of trees in natural forests. Through a field survey in the area with a remarkably low growth, high-density planting problem, soil was found to have excess-moisture and there was the problem of Pueraria lobata covering. As a result of the analysis of the soil, it was found that its organic content in the soil was lower; soil pH was higher; and microbial activities in the soil were lower when compared to that of natural forests.

• Journal of the Korean Wood Science and Technology
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• v.47 no.5
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• pp.633-643
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• 2019

Growth characteristics [stem diameter (D), tree height (H)] and wood properties [Pilodyn penetration (P) and stress-wave velocity (SWV)] were measured for 65 families of 6-year-old Acacia mangium trees planted in Indonesia, in order to characterize their variation in D, H, P, and SWV. Therefore, the correlations between the measured characteristics were also determined, and their significant differences observed. Furthermore, their low to moderate values of narrow-sense heritability was obtained, and the results indicated the characteristics to be genetically controlled in A. mangium. In addition, highly significant positive correlations were observed among the growth characteristics, suggesting a close relationship, while there was no significant association between the growth characteristics and P, as well as SWV, indicating their independent. Therefore, these results demonstrate a potential for the improvement of both growth and wood properties of A. mangium trees, using the appropriate breeding programs. In addition, 18 families showed good performance in D and SWV, signifying their positive prospect of being considered as plus trees for the next generation breeding cycles.

• Korean Journal of Environment and Ecology
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• v.28 no.4
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• pp.457-471
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• 2014

This study aims to present an evaluation scheme to improve the problems in tree shapes and tree growth which were identified through shape and growth assessments of landscape trees currently planted in Haedoji Park, Songdo, Incheon Metropolitan City after plant structure status and propriety review for funtion of space and concept of planting. Suitability the planting concept was evaluated according to function of space. The result indicated that the shade planting areas accounted for 29.5% of the the shade spaces area. 58.7%, respectively planting areas of visual landscape. And 11.8%, respectively planting areas of buffer. Because the planting areas was lacked according to the park established spatial configuration of central facilities and the result of plant young trees. Plant structure status required consideration with plant structure, density, size, growth status for improve planting function. The tree assessment was performed on a total of 28 species and 600 trees of which 22 species and 209 trees were planted in the buffer zone, 8 species and 71 trees in the shade zone, 16 species and 266 trees in the visual landscape zone, and 4 species and 54 trees in the ecological landscape zone. The trees were divided into grades based on their assessment score and were statistically grouped by the functional zone in where they are planted and by tree species to verify their significance. The tree shape assessment was an average of 56.6 points and the tree growth assessment was an average of 76.0 points. Using the results of the tree assessments, the tree standards for each functional space were identified and a concept of optimum planting and cultivating was applied. When applying the shape assessment results by zone to the concept of planting, since trees for buffering require high functionality they received E's, the lowest grade; as trees for ecological landscaping require diverseness and naturalness, they received D's; since trees for shading require utilization, they received C's as trees with branching at the main stems were considered; and since trees for visual landscaping required aesthetical value, they received A's and B's. When applying the growth assessment results by zone to the concept of planting, based on planting foundations of favorable and poor, for buffering, visual landscaping, and ecological landscaping, trees from grades A to E could be planted, and for shading, trees from grades A to C could be planted. For a cultivation plan that could improve the growth of the trees, we proposed that the topography of the land be selected considering the tree's characteristics and that a method of pot seeding be used. Also, to improve the shape of the trees, we proposed that poles be used to improve the growth of vertically-straight stems, an appropriate planting density be applied for reasonable branch growth, manage tree shape to maintain good crowning, and better manage fertilization to maintain a reasonable crown density.

• Korean Journal of Environment and Ecology
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• v.36 no.3
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• pp.338-349
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• 2022

This study aims to investigate whether modular community planting, which entailed planting a variety of species of seedlings at high density, was more effective in restoring natural forests than the existing mature tree planting. We also investigated whether the planting density of the modular community planting facilitates growth or improves the tree layer coverage. We conducted outdoor experiments in which the samples were divided into a mature tree planting plot (control plot), where mature trees were planted at wide intervals, and a modular community planting (MCP) plot (treatment plot), where multiple seedlings were planted in high density. The MCP plot was further divided into the plot in which 3 seedlings were planted per m² and the plot of 1 seedling per m². We measured the specimens' survival rate, growth rate (tree height, crown width, and root collar diameter), and cover rate for 26 months from May 2019 and the predicted future tree height growth using the measured tree height. The survival rate and relative growth rate of the MCP were higher than those of the mature tree planting plot. The vertical coverage rate of the tree crown in the MCP exhibited complete coverage of the ground before 23 months, while the coverage rate of the mature tree planting decreased due to transplantation stress. The seedlings in the MCP, which were planted at high density, grew well and were predicted to grow higher than the mature trees in the large tree planting plot within 5 to 6.5 years after planting. It was due to multiple species, seedlings, high-density planting, and planting foundation improvements, such as soil enhancement and mulching. In other words, the seedlings planted in the MCP had a higher survival rate as their environmental adaptation after planting was better, and their early growth was also larger than the trees in the mature planting plot. The high-density mixed planting of various native species not only mitigated the inter-complementary environmental pressures but also facilitated growth by inducing competition between species. Moreover, the planting foundation improvement effectively increased the seedlings' viability and growth rate. A reduction in follow-up management costs is expected as the tree layer coverage sharply increases due to the higher planting density. In the MCP (3 seedlings per m² and 1 seedling per m²), the tree height growth was promoted with the higher planting density, and the crown width and root collar diameter tended to be larger with the lower planting density, but these differences were not statistically significant.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.6
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• pp.49-60
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• 2008

In this study, the green zone patterns of sidewalks are classified 'one street-tree row + building,' 'one street-tree row + green zone,' 'two street-tree rows + building,' and 'two street-tree rows + green zone' and assessed their visual characteristic in order to provide desirable measures for scenery design. As a result of the analysis of visual images of sidewalk, the scenery in which street trees are planted in one row was generally assessed to be negative, while roads where green zones rather than buildings are adjacent were revealed to seem stable and pleasant. The scenery in which street trees are planted in two rows was assessed highly in an image of 'extensionality' indicating street circumstances, and especially the pattern 'two street-tree rows + green zone' was shown to be the most beautiful scenery. According to the results of factor analysis of sidewalks, three factors were identified : 'extensionality' showing sidewalk circumstances; 'peculiarity' including unique personality, and 'pliability' showing the organic flow of the scenery. The results of the analysis of visual preference of the scenery according to green zone patterns showed that the 'two street-tree rows + green zone' was measured to be highest. When buildings are adjacent to a sidewalk, two street-tree rows rather than one street-tree row were assessed to increase preference. As for the correlation between visual factors and preference analyzed through multiple regression analysis, all 'extensionality,' 'peculiarity,' and 'pliability' were revealed to show positive correlation for visual preference.