• Korean Journal of Environmental Biology
• /
• v.24 no.4
• /
• pp.314-328
• /
• 2006

This study was attempted to investigate the flora of Seodaesan (903.7 m). The flora of Seodaesan was investigated from August in 2001 to October in 2003. Vascular plants of this area consist of total 465 taxa; 1 hybrid, 3 forma, 59 varieties, 402 species, 287 genera, 94 families. It corresponds to 11.4% of totally 4,071 taxa appeared in Korea. Useful plants of this area were investigated 388 taxa. It corresponds to 83.4 % of collected plants in this area under our study. Among the useful plants, there are 199 taxa of edible source, 186 taxa of pasture source, 162 taxa of medicinal source, 100 taxa of ornamental source, 20 taxa of timber, and 3 taxa of industrial raw materials. Korean endemic plants were composed 10 families, 11 genera, 12 species and totaling 12 taxa. Naturalized plants were composed 11 families, 18 genera, 22 species and totaling 22 taxa.

• Journal of the Korean Applied Science and Technology
• /
• v.35 no.1
• /
• pp.247-253
• /
• 2018

To replace the imported biomass and to effectively cope with growing RPS(Renewable Portfolio Standard) in power sector, the domestic forest biomass resources for wood pellets were estimated from the preceding research and annual growth rate of forest trees in this study. Assuming that 20% of the by-product from forest trees processing were used as raw material for wood pellet and the wood pellet production capacity was based on the average value derived from the above two methods, unused by-product and residues generated 1.99million tons in 2016, 2.28million tons in 2020 and 3.08million tons in 2030. If 20% of by-products(pebbles, sawdust, etc.) from roundwood processing were used as raw material for wood pellets, the wood pellet could be produced 2.74million tons/year in 2016, 2.95million tons/year in 2020, 3.98million tons/year in 2030. Therefore, total amounts of wood pellet would be increased to 2.74million tons/year in 2016, 3.14million tons/year in 2020, 4.23million tons/year in 2030 when it considered unused by-product and residues from wood processing as raw materials.

• Journal of the Korean Wood Science and Technology
• /
• v.43 no.3
• /
• pp.320-326
• /
• 2015

Mechanical properties of woods are easily affected by the differences of site environment such as soil and climate changes. In this study, the relationship between mechanical properties and growth factors for Cryptomeria japonica stands in Jeollanam-do Province, Gyeongsangnam-do Province and Je-ju island was analyzed. From these plot data, bending strength, compressive strength, and shear strength were analyzed by Duncan's new multiple range test. The results of Duncan's new multiple range test analysis indicated that bending strength, compression strength, and shear strength were positively related to tree mean height, and stem number per ha, respectively, while they were inversely proportional to DBH (diameter at breast height), elevation, and soil drainage. As a result of this study, there are high correlations between mechanical properties of wood and stand characteristics of Cryptomeria japonica by the region, this findings are very useful to apply the silvicultural treatment system to produce high quality timber as a basic data on this species (distributed in southern region of Korea).

• Journal of the Korean Wood Science and Technology
• /
• v.41 no.1
• /
• pp.42-50
• /
• 2013

Since 1990's, a plywood for flooring base has gotten customers' demand. Costs of raw material and production increased because of changed environment of industry. Tropical timber such as Red Meranti (Shorea acuminate) used for raw material of the floor has been depleting beside countries in South Eastern Asia changed species of afforestation. As a result, it gets hard to secure good quality of raw material for plywood. Moreover plywood price is increased suddenly after earthquake in Japan. Eucalyptus (Eucalyptus globulus) in china has been using for raw material as a countermeasure of changed environment of industry. In this study, possibility of using flooring consisted of Eucalyptus veneer as crossband layers was checked by deflection experiments. Flooring consisted of Red Meranti was used for comparison. Two factors which impact on deflection are a type of density gradient and density difference between Long-grain veneer and Short-grain veneer. Red Meranti samples are M type of density gradient on the other hand Eucalyptus samples are W type of density gradient. The more samples have high density difference, the more deformation was checked. A sample which has big density difference between core and cross bands layer warp more also deform. Flooring was deformed smaller than plywood and samples which have big density difference was deformed more.

• Journal of the Korean Wood Science and Technology
• /
• v.41 no.3
• /
• pp.201-210
• /
• 2013

The purpose of this study was to examine the species of 117 wooden elements which were used in the Daewungjeon Hall (National Treasure No. 805, constructed in A. D. 1659) of Bukjijangsa Temple, Daegu, Korea. Pillars were identified as 5 red pines (hard pines; most likely, Pinus densiflora S. et Z.), 2 Cerris section of subgenus Lepidobalanus (deciduous oaks) and 3 Tsuga spp. Hwalju columns were 3 Abies spp. and 1 red pine. Head-penetrating ties were 8 red pines and 1 Cerris sp.; Pyeongbang, 3 red pines and 6 Cerris spp. Purlins were identified as 17 red pines, 16 Cerris spp. and 1 Tsuga sp. Angle rafters were 3 red pines and 1 Cerris sp., and end angle rafters, 2 red pines, 1 Zelkova serrata and 1 exotic hard pine. All of brackets (31 woods), jangyeo (4) and deot-chunyeo (2) were identified as red pines. As a whole, red pines (70.1%) and Cerris (22.2%) were major species used in the Daewungjeon Hall of Bukjijangsa Temple. Tsuga, Abies and exotic hard pines seem imported woods used for recent repairs.

• Journal of the Korean Wood Science and Technology
• /
• v.46 no.1
• /
• pp.85-92
• /
• 2018

In order to use glued built up timber beam as a structural member for post and beam construction, it must be possible to manufacture long-span lumber. In this study, the researchers conducted a performance evaluation for longitudinal bonding of lumber (cross-section $89{\times}120mm$) made from larch. The specimens were prepared in six different forms using the longitudinal bonding method. The bonding strength of these specimens was tested through tensile strength tests and bending strength tests. The tensile strength test result of the longitudinally bonded parts was better than that of the double lap specimens. And, the tensile strength value of the scarf specimen was better than that of the hooked scarf specimen. The tensile strength of the GFRP (Glass Fiber Reinforced Plastic) rod insertion bonding specimen was 3.6 MPa, which was the highest. As for the bending strength test result of the longitudinally bonded part, the average MOR (modulus of rupture) of the specimen where a GFRP rod was inserted and bonded measured 29 MPa, while the specimens of other bonded parts showed a MOR no more than 11 MPa. Toughness destruction was observed in specimens where a GFRP rod was insertion-bonded. The rest of the specimens showed brittle destruction. The average MOR strength of the Rod + Lap specimen was 30.5 MPa, which was the highest among all longitudinally bonded specimens. The bending strength of the Rod + Lap specimens showed an effective strength that was 66% of that of the control group which were not longitudinally bonded.

• Korean Journal of Plant Resources
• /
• v.24 no.5
• /
• pp.521-539
• /
• 2011

This study was carried out to investigate the flora of Mt. Gahyeon (Gyeonggi-do, Gimpo). The vascular plant were collected 13 times (from March to Oct. 2010), and 413 taxa in total were identified, including 96 families, 267 genera, 362 species, 6 subspecies, 40 varieties and 5 forms. Among them were 6 taxa of Korean endemic plants and 17 taxa of specially designated plants by the Ministry of Environment. Usage of 413 taxa were consists of 159 taxa (38.5%) of edible plants, 122 taxa (29.5%) of medicinal plants, 77 taxa (18.6%) of pasture plants, 47 taxa (11.4%) of ornamental plants, 26 taxa (6.3%) of stainable plants, 14 taxa (3.4%) of timber plants, 6 taxa (1.5%) of fiber plants, 5 taxa (1.2%) of industrial plants and 102 taxa (24.7%) of unknown resource plants, respectively. The naturalized plants were identified as 41 taxa and the percent of naturalized index (NI) was 9.9% of total 413 taxa vascular plants. Furthermore, therophytes (27.1%), hemicryptophytes (26.4%), geophytes (14.7%) showed high proportional ratio in life form spectrum.

• Korean Journal of Plant Resources
• /
• v.29 no.2
• /
• pp.204-224
• /
• 2016

This study was carried out to investigate the vascular plants of the protected area for forest genetic resource conservation in the Korea national Baekdudaegan arboretum. The vascular plants collected 12 times (from April 2007 to August 2014) were consisted of total 569 taxa; 89 families, 289 genera, 489 species, 5 subspecies, 66 varieties and 9 forms respectively. The 20 taxa of Korean endemic plants and 21 taxa of Korean rare plants were investigated. The floristic regional indicator plants found in this area were 112 taxa comprising 2 taxa of grade V, 8 taxa of grade IV, 23 taxa of grade III, 40 taxa of grade II, 39 taxa of grade I. The introduced and naturalized plants were counted as 22 taxa, therefore naturalized ratio was 3.8%. 577 taxa listed consists of 223 taxa (39.2%) of edible plants, 168 taxa (29.5%) of medicinal plants, 202 taxa (35.5%) of pasture plants, 58 taxa (10.2%) of ornamental plants, 26 taxa (4.6%) of timber plants, 5 taxa (0.9%) of fiber plants and 4 taxa (0.7%) of industrial plants.

• Korean Journal of Plant Resources
• /
• v.29 no.2
• /
• pp.264-280
• /
• 2016

This survey was conducted in order to investigate the vascular plants of Mt. Goryeong and Gaemyeong in the DMZ area of Korea. The vascular plants were collected eight times from April 2014 to October 2014 and consisted a total of 450 taxa; 91 families, 279 genera, 391 species, 4 subspecies, 49 varieties and 6 forms. The observed rare plant species as designated by Korea Forest Service were 5 taxa including Tylophora floribunda Miq., Aristolochia contorta Bunge, Viola albida Palib., etc. Endemic plant species were 6 taxa containing Aconitum pseudolaeve Nakai, Clematis brachyura Maxim., Clematis trichotoma Nakai, etc. 33 taxa were listed as specific plant species based on phytogeographical in the investigated area. 35 taxa were recorded as naturalized plants, and their naturalized rate and urban index were noted as 7.7%, and 10.9%, respectively. Of the 450 taxa listed; 186 were edible plants, 173 pasture plants, 149 medicinal plants, 51 omamental plants, 20 timber plants, 13 stain plants, 4 fiber plants, 4 industrial plants and 92 unknown resource plants.

• Korean Journal of Plant Resources
• /
• v.21 no.2
• /
• pp.148-161
• /
• 2008

This study was performed to investigate the distribution of vascular plants and their usefulness in Mt. Hwaak (931m). The vascular plants were consisted of total 338 taxa; 92 families, 248 genera, 281 species, 1 subspecies, 47 varieties and 9 forms. It corresponded to 6.9% of totally 4,881 taxa distributed in Korea. The economic plants of this area were 278 taxa. It corresponded to 82.2% of collected plants in this area. Among the economic plants, there were 154 taxa of edible source, 163 taxa of medicinal source, 58 taxa of ornamental source, 91 taxa of pastural source, 22 taxa of industrial source and 9 taxa of timber source. Korean endemic plants of this area were 9 taxa. The rare and endangered plants was 1 taxon, and the specific species floristically of $I\;{\sim}\;V$ grades were 21 taxa. The naturalized plants were 19 taxa and naturalized ratio was 5.6% and Urban index was 6.8%.