• Journal of Korean Society of Forest Science
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• v.86 no.4
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• pp.502-508
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• 1997

Black locust(Robina pseudo-acacia L.) and hornbeam trees(Carpinus laxiflora BL.) are widely growing in Korea and have relatively good wood qualities. However, they have seldom been used as industrial materials. This study was carried out to investigate the effect of wood moisture content on microwave-bending processing. The bending processing of the both species are improved as the increase of wood moisture from 30% to green, and the maximum limit of wood moiture content is 50%. The minimum solid-bending radii of black locust and hornbeam green wood were 60mm and 40mm for micro-wave bending, respectively. In conclusion, the microwave-heated green wood showed very good bending processing properties for bent-wood furniture.

• Journal of the Korean Wood Science and Technology
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• v.43 no.2
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• pp.156-167
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• 2015

The aim of this study was to determine the physical and mechanical properties of glued laminated timber (glulam) manufactured from small-diameter logs of three wood species, Acacia mangium (mangium), Maesopsis eminii (manii), and Falcataria moluccana (sengon), with densities of 533, 392, and $271kg/m^3$, respectively. Glulam measuring 5 cm by 7 cm by 160 cm in thickness, width, and length, respectively, was made with three to five lamina, or layers, and isocyanate adhesive. The glulams contained either the same wood species for all layers or a combination of mangium face and back layers with a core layer of manii or sengon. Solid wood samples of the same size for all three species were included as a basis for comparison. Physical-mechanical properties and delamination tests of glulam referred to JAS 234:2003. The results showed that the properties of same species glulam did not differ from those of solid wood, with the exception of the shear strength of glulam being lower than that of solid wood. Wood species affected glulam properties, but three- and five-layer glulams were not different except for the modulus of elasticity. All glulams were resistant to delamination by immersion in both cold and boiling water. The glulams that successfully met the JAS standard were three- and five-layer mangium, five-layer manii, and five-layer mangium-manii glulams.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.4
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• pp.85-97
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• 2010

This study analyzed the distribution, structure and environmental condition of the vegetation of the Chionanthus retusus Lindly et Paxton community at the Wansanchielbong in the Jeonju city to offer basic data for sustainable conservation and ecological management system. And the results are as follows; 1. The average pH of soil at the community was pH 5.69 and it was slightly higher than the average of forest soil pH of Korea. But if the degree of pH will be down, it will be needed some more fertilization of Calcium. 2. The total average for contents of organism was 4.98%. And the nitrate - nitrogen content(mg/kg) of A, B, C, D quadrat was 20.29%, 28.87%, 7.65%, and 23.3% respectively. And there were good condition except quadrat C which was contaminated by amount of earth and sand. 3. The flora of the Chionanthus retusus Lindly et Paxton community was listed as 60 taxa; 37 families, 50 genera, 47 species, 10 varieties and 3 forms. The average appearance species of each Quadrat were A sector 30, B sector 26, C sector 19 and D 19 taxa respectively. 4. Surveyed woody plants in the community were as follows : Chionanthus retusus, Zelkova serrata, Quercus variabilis, Cornus walteri, Robinia pseudo-acacia and those were mixed status. And Chionanthus retusus, Zelkova serrata, Robinia pseudo-acacia, Albizzia julibrisin, Cudrania tricuspidata, Symplocos chinensis for. pilosa were mixed in mid layer trees. Herbaceous plants were founded such as Chionanthus retusus, Zelkova serrata, Robinia pseudo-acacia, Grewia parviflora, Rosa multiflora, Trachelospermum asiaticum was dominant with 35~64% in the ground cover, and Commelina communis, Calamagrostis arundinacea, Dryopteris bissetiana, Lilium lancifolium were founded also. 5. The importance values of Chionanthus retusus was 40.2% in the quadrat A1, 50.2% at quadrat A, 50.0% B1, 45.2% B2, 22.4% C1, 73.6% C2, 33.2% D1 and the total average of I.V. was 44.9%. 6. The average height of surveyed Chionanthus retusus was 5.7m and the average DBH was 12.4cm. The number of trees higher than 2m were 107 and the number of trees lower than 2m were 63. The total numbers of Chionanthus retusus were 170. 7. The age of surveyed Chionanthus retusus were analyzed 42 thru 87 years old and that of Zelkova serrata were 42, Quercus variabilis were 60, Quercus aliena were 48, Robinia pseudo-acacia were 40. 8. The number of trees with DBH 40 through 50cm were 6, and that of 30~39cm were 3, and that of 20~29cm were 16, so the total number that was over 20cm was 25. And there were 70 trees under 10cm of DBH and 63 seedlings. It will be very important data to conserve the habitat that the structure and environmental condition of the Chionanthus retusus Lindly et Paxton community at the Wansanchielbong was stable, and sustainable monitoring will be needed. Now that community is nurse forest of Jeonju City but more positive preservation plan will be needed and assigning monument of city or province also be necessary.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.231-237
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• 2006

Grease barrier food containers are commonly used for packaging of fast food, cooked food, and food in general. Greaseproofing is also used for certificate paper and label paper etc. Different pulp raw materials, due to their different fiber morphology and chemical compositions, produce papers of varying characteristics. We used optical photomicroscopy and fiber analysis data to evaluate fiber morphology and traits under various beating conditions in order to understand which pulp raw materials produced superior greaseproofing property when a fluorinated greaseproofing agent was added internally. The experiment studied 9 species of pulps, including 2 softwood (northern pine and radiata pine) bleached kraft pulps which were beaten to 550 and 350 mL CSF, respectively; 3 hardwoods (eucalypts, acacia, mixed Indonesian hardwoods) bleached kraft pulps which were beaten to 450 and 250 mL CSF, respectively; and nonwood fibers of reed, bagasse, and abaca. A fluorinated greaseproofing chemical at 0.12% dosage with respect to dry pulp was added to each pulp preparation and formed handsheets. A total of 67 sets of handsheets were prepared, and their basis weights, thickness, bulks, opacities, wet opacities, air resistance, water absorption and degrees of greaseproofing were measured for an overall evaluation of pulp and freeness on greaseproofing papers. The experimental fiber length, coarseness and distribution characteristics and the greaseproofing results suggest that softwood pulps (radiate pine > northern pine) were superior to hardwood pulps (eucalypts > acacia > mixed Indonesian hardwoods). The unbeaten pulps gave papers with high porosities and nearly devoid of greaseproofing property. Greaseproofing is proportional to air resistance. Among the nonwood fibers, bagasse had the best greaseproofing property, followed by reed and abaca was the poorest. With regards to waterproofing property, hardwood pulps (mixed Indonesian hardwoods > acacia > eucalypts) were better than softwood pulps (northern pine > radiate pine). Among the Nonwood fibers, reed had the highest waterproofing property, and it was followed by abaca, while bagasse had the poorest waterproofing characteristic. In summary, bleached kraft northern pine, eucalypts and reed pulps were best suited for making greaseproofing papers, Freeness of the pulps should be kept at $200{\sim}280mL$ CSF for optimal performance.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.1
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• pp.41-51
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• 1990

This study was executed to investigate the vegetation structure and to propose the vegetation management proposals of the Sansung Nature Park at Cheonju City and the results were as fellows. 1. A damage of vegetation and soil surface around the Namgosa was taken place up to 100m by picnic 2. Pinus rigida forest covered 36.1% of the total area(152.6ha) and total afforested vegetation covered 43.5%, respectively. P. denstflora comm. covered 28.4% arid Carpinus laxiflora Comm. as a climax vegetation in temerate zone covered 0.3%, respectively. 3. 6, 7 and 8 of the degree of human disturbance of vegetation covered 45.3%, 26.6% and 21.4%, respectively and resulted in low quality of naturalness. 4. Physical and chemical properties of soil were pour at high elevation and were poor severely in and around the Namgosa due to human disturbance. 5. Plant community were under rapid succession and had unvalanced structure and heterogeneous composition of species. Rapid vegetational succession from Pinus densiflora and Pf. rigida to Carpinus laxifora, Quercus spp. and Robinina pseudo-acacia were taken place.6. The speeies of Raunkiaer's frequency class I as of high frequency class were Pinus dunsiflora, Carpinus alxiflora, Quercus mmongolica, Sorbus alnifolia, Prunrs sargintii, Rhododendron yedoense, Stephanandra incisa and Lespedeza maxinowiczii. 7. Vegetational management proposals were made for three vegetation zones ; Historic landscape restoration and preservation zone, Afforested vegetation zone, Native vegetation conservation zone and recommanded native species for landcape planting.

• The Korean Journal of Ecology
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• v.8 no.2
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• pp.81-87
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• 1985

The vegetation on the north and south slopes of Kwanak mountain was assessed and recorded during thesummer of 1976. Recordings were made of 5*5m quadrats placed along the transects running parallel to the slopes. On the north slope, most of large trees such as Alnus sibirica, Sorbus alnifolia, Robinia pseudo-acacia and Pinus rigida make the crown and their mean DBH was conspicuously large, while the vegetation of south slope is dominated by dwarf Juniperus utilis, Pinus densiflora, Weigela florida var. glabra which are considered as a resistant species of dry site. The amount of humus, total nitrogen, soil water content and available phosphorous is higher on the north slope than the south one. However, the soil pH is higher on the south slope. It is assumed that the humus content is a main factor to make difference on the type of vegetation between the north and south slope.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2003.11a
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• pp.17-26
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• 2003

Nalita wood(Trema orientalis) is one of the fastest growing woods in the world. It may be a viable species for pulpwood. The physical, chemical and morphological properties of Nalita were studied. The total lignin, pentosan and holocellulose content in Nalita wood were 24.7%, 22% and 81.2%, respectively. Its fiber length was about 0.92 mm, which are comparable to Acacia mangium. Nitrobenzene oxidation of Nalita wood meal indicated that the guaciayl and syringyl unit were the major constituent of Nalita lignin. Nalita produced 50% pulp yield at Kappa number 21 in soda-anthraquinone process. The strength properties of Nalita pulp were comparable to other tropical hardwood pulp. At $40_{\circ}$ SR, the breaking length, burst index, tear index and total energy absorption were 6000 m, $3.5kPa{\cdot}m^2/g\;and\;7.0mN{\cdot}m^2/g\;and\;75J/m^2$, respectively.

• The Korean Journal of Ecology
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• v.15 no.4
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• pp.411-431
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• 1992

The present study was undertaken to classify and describe the vegetation around andong dam area, kyong-buk, korea$(36^{\circ}\;35^{\prime}\;N, \;128^{\circ}\;47^{\prime}\;E)$ by methods of the ZM school of phytosociology. The investigations were carried out in the plot. The homogeneous part of forest and grass communities was analyzed by recording the combined scale of cover-abundance and sociability of all species found in the plot. The community data obtained were classified into two associations and seven communities; festuco onvinae-pinetum densiflorae assoc. nov., quercetum variabili-serratae, quercus acutissima community, larix leptolepis, populus tomentiglandulosa, acer canadensis, prunus spp. afforestations, robinia pseudo-acacia-commelina communis community and acer palmatum cv. afforestation. The grass vegetation was divided into six associations and seventeen communities; lactuco indicae- humuletum japonicae, eragrostio ferruginei-plantaginetum asiaticae, polygonetum thunbergii, phragmitetum japonicae, eragrostio ferruginei-plantaginetum asiaticae, polygonetum thunbergii, phragmitetum japonicae, artemisio-potentilletum chinesis, eleusinetum indicae, amorpha freticosa, artemisia princeps, achyranthes fauriei and other fourteen communities. amoung the above vegetationship of the vegetation units with their environments was outlined.

• Journal of Forest and Environmental Science
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• v.34 no.2
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• pp.145-152
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• 2018

Quantification of Carbon stock has become in the contest of changing climate and mitigation potential of forests. Two different forest types, Dry Shiwalik Sal Forest and Moist Shiwalik Sal Forest in Barkot and Lachchiwala of Doon Valley, Western Himalaya are selected for the study. Volume equations, destructive sampling and laboratory analysis are done to estimate the carbon stock in different carbon pools like trees, shrubs, herbs and soils. Considerable variations are observed in terms of carbon stocks in different forest types. In Dry Shiwalik Sal Forest, carbon stock density varied between 129.81 and $136.00MgCha^{-1}$ while in Moist Shiwalik Sal Forest, carbon stock density ranged from 222.29 to $271.67MgCha^{-1}$. Tree species like Shorea robusta, Syzigium cumini, Miliusa velutina, Acacia catechu, and Mallotus philippensis had significant role in carbon sequestration. Shorea robusta had contributed highest in carbon stock due to highest density. Total of 2,338,280.165 Mg carbon stock was estimated in all the forest types.

• The Korean Journal of Ecology
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• v.6 no.1
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• pp.33-44
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• 1983

Vegetatiion structure and population dynamcis of pine needle gall midge were investigated from 1980 to 1982 at the southern part of Palgong mountain near Daegu. The results of investigation at the areas of A (pure stand), B(30% mixed forest) adn C(60% mixed forest) were as follow; Vegeation of 3 areas were not classified by the species diversity, but by the unequal distribution of Alnus hirsuta, Robinia pseudo-acacia, Lespedeza cyrtobotrya, Quercus variabilis and vitality of Pinus densiflora at the area C was low, due to shadow by broad-leaf trees. Soil environmental factors at 3 areas not characteristic, but the average of humus contents showed high significance and the order was A