• 제목/요약/키워드: Larix

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韓國의 森林構造에 따른 物質生産力에 관한 分析 - 年齡生長 分析에 의한 森林 樹木의 最高生産力期 및 最適伐採期 推定모델 - (Studies of the Forest Structure and Productivity in Korea -Models of Maximum Productivity and Optimum Cutting Time of the Forests by Annual Ring Growth analyses-)

  • Chang, Nam-Kee;Kim, Heui-Baek;Oh, In-Hye;Chang, Myung-Ae
    • The Korean Journal of Ecology
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    • 제13권3호
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    • pp.191-202
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    • 1990
  • For the maximun yield of the forest trees in the forest management, the growth of annual ring area of the major forest trees was analysed in the four areas in South Korea. The time to the maximum productivity and the optimum cutting time for the maximum yield were estimated. The growth curve of annual ring area showed sigmoid like that of other organisms. Only the growth coefficient among the areas between Fraxinus rhynchophylla and Pinus koraiensis represented significance (5% level). The growth coefficient among forest trees between Pinus densiflora and Abies holophylla, Larix kaempferi and Carpinus laxiflora, Larix kaempferi and Quercus mongolica, Larix kaempferi and Quercus serrata, Larix kaempferi and Pinus koraiensis, and Larix kaempferi and Abies holophylla represented significance (5% level). Among eight forest trees, the time to maximum productivity (tm) of Larix kaempferi was the earliest (21.4 year), and Abies holophylla was the latest (91.9 year). The optimum cutting time for the maximum yield (tc) of L. kaempferi was the earliest (29.4 year) and that of A, holophylla was the latest (122.2 year) of all communities. The optimum cutting time for the maximum yield was 1.33 times as late as the time to the maximum productivity. If the growth of annual ring area as the forest tree for wood is regarded, L. kaempferi and P. densiflora are thought to be more economical than A. holophylla and P. koraiensis.

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Influence of Composition of Layer Layout on Bending and Compression Strength Performance of Larix Cross-Laminated Timber (CLT)

  • Da-Bin SONG;Keon-Ho KIM
    • Journal of the Korean Wood Science and Technology
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    • 제51권4호
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    • pp.239-252
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    • 2023
  • In this study, bending and compression strength tests were performed to investigate effect of composition of layer layout of Larix cross-laminated timber (CLT) on mechanical properties. The Larix CLT consists of five laminae, and specimens were classified into four types according to grade and composition of layer. The layer's layout were composited as follows 1) cross-laminating layers in major and minor direction (Type A), and 2) cross-laminating external layer in major direction and internal layer applied grade of layer in minor direction (Type B). E12 and E16 were used as grades of lamina for major direction layer of Type A and external layer of Type B according to KS F 3020. In results of the bending test of CLT using same grade layer according to layer composition, the modulus of elasticity (MOE) of Type B was higher than Type A. In case of prediction of bending MOE of Larix CLT, the experimental MOE was higher than 1.00 to 1.09 times for Shear analogy method and 1.14 to 1.25 times for Gamma method. Therefore, it is recommended to predict the bending MOE for Larix CLT by shear analogy method. Compression strength of CLT in accordance with layer composition was measured to be 2% and 9% higher for Type A using E12 and E16 layers than Type B, respectively. In failure mode of Type A, progress direction of failure generated under compression load was confirmed to transfer from major layer to minor layer by rolling shear or bonding line failure due to the middle lamina in major direction.

잣나무재와 일본잎갈나무재의 방사방향 방사조직 밀도 및 연륜 내 복열방사조직 출현 빈도수 변이 (Radial Variations of Ray Spacing and Intra-annual Variation of Biseriate Ray Frequency in Pinus koraiensis and Larix kaempferi Woods Grown in Korea)

  • 김남훈
    • Journal of the Korean Wood Science and Technology
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    • 제37권6호
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    • pp.531-536
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    • 2009
  • 주요 국산 수종인 잣나무재와 일본잎갈나무재의 횡단면상 방사조직 밀도 및 접선단면상 복열방사조직 출현 빈도수에 대한 변이성을 조사하였다. 방사조직의 밀도는 잣나무재 4.6개/mm, 일본잎갈나무재 9.0개/mm로 일본잎갈나무재의 방사조직 밀도가 더 높게 나타났다. 또한, 방사조직 밀도는 수 부근에서 높았고, 수피 쪽으로 이행함에 따라 점차 감소하는 경향을 나타냈다. 한 연륜 내에서의 복열방사조직 출현 빈도수는 일본잎갈나무재가 잣나무재보다 높았다. 잣나무재의 복열방사조직은 복열의 수가 1세포고인 것(B+1)이, 일본잎갈나무재는 2세포고인 것(B+2)이 가장 많았다. 일반적으로 복열방사조직의 출현 빈도수는 조재부가 만재부보다 높았는데 일본잎갈나무재의 경우 복열의 수가 6~7세포고에 달하는 것(B+6~B+7)도 있었다. 본 연구 결과, 방사조직 밀도의 변이성은 성숙재와 미성숙재를 구분하는 기초 자료로뿐만 아니라 방사조직의 출현 빈도와 함께 두 수종을 식별하는 자료로도 활용될 수 있을 것으로 생각되었다.

일본잎갈나무림과 침활혼효림의 입지환경이 산양삼 종묘의 초기 생육에 미치는 영향 (Effect of Location Environments on Early Growth of Wild-simulated Ginseng (Panax ginseng C. A. Meyer) Seedlings in Larix kaempferi and Mixed Forest)

  • 김기윤;엄유리;정대희;어현지;전권석;김현준
    • 한국산림과학회지
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    • 제109권3호
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    • pp.313-324
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    • 2020
  • 본 연구는 일본잎갈나무림과 침활혼효림의 입지환경이 산양삼 종묘의 초기 생육에 미치는 영향을 구명하기 위해 수행하였다. 일본잎갈나무림과 침활혼효림에 시험포지를 조성하고, 입지환경과 산양삼 종묘의 생육특성을 조사하였다. 입지환경 중에서 토양 유기물, 전질소, 양이온치환용량과 같은 토양특성은 일본잎갈나무림에 비해 침활혼효림에서 높게 나타났고, 산양삼 종묘의 생육특성 또한 일본잎갈나무림에 비해 침활혼효림에서 유의적으로 높게 나타났다. 시험포지 내 수종 비율, 토양특성, 산양삼 종묘 생육특성 간의 상관관계를 분석한 결과, 토양특성과 생육특성은 활엽수림의 비율과 유의적인 정의 상관관계를 보였고, 토양특성 중에서 유기물, 전질소, 양이온치환용량이 산양삼의 생육과 유의적인 정의 상관관계를 보였다. 본 연구에서는 일본잎갈나무림과 침활혼효림의 입지환경 중에서 임상과 토양특성이 산양삼 종묘 생육특성과 유의미한 상관관계를 보이는 것을 구명할 수 있었고, 본 연구의 결과를 바탕으로 향후 산양삼의 최적 재배지를 선정하는데 기초적인 자료로서 도움을 줄 수 있을 것으로 사료된다.

낙엽송으로부터 배출되는 자연 VOC 배출속도 및 배출특성 연구 (Study on Natural VOC Emission Rates and Characteristics Emitted from Larix Leptoleis (Sieb. et Zucc.) Gordon)

  • 김기준;김조천;임준호;선우영;박현주;조규탁
    • 한국환경과학회지
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    • 제16권2호
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    • pp.151-158
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    • 2007
  • In order to investigate the compositions and the emission rates of monoterpenes emitted from coniferous trees, those from Larix leptoleis (Sieb, et Zucc.) Gordon were measured. In spring and summer, the major monoterpenes were ${\alpha}-terpinene,\;{\alpha}-pinene$, myrcene; however, ${\alpha}-pinene\;and\;{\alpha}-terpinene$ were most abundant in fall. The total mean monoterpene emission rates were $0.455\;({\mu}gC/gdw/hr)$ during the whole period. The higher monoterpene emission rates were found in fall compared to those in spring and summer. In addition, the slopes (${\beta}\;value$) between emission rate and temperature were two times lower in fall than those in spring and summer. It was also found that Larix leptoleis (Sieb. et Zucc.) Cordon had lower monoterpene emission rates than P. densiflora and P. rigida.

경기도 광릉시험림의 구주낙엽송, 스트로브잣나무, 서양측백 조림지 토양내 질소 무기화 비교 (Differences of Nitrogen Mineralization in Larix decidua, Pinus strobus and Thuja occidentalis Plantations of the Kwangeneung Experimental Forest, Kyonggi Province)

  • Son, Yowhan;Im-Kyun Lee;Jung-Tae Kim;Sang-Eun Lee
    • The Korean Journal of Ecology
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    • 제18권3호
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    • pp.385-395
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    • 1995
  • Species effects on soil nitrogen mineralization and nitrification in the top 15 cm of soil were evaluated using the buried-bag incubation method in three coniferous plantations in the Kwangneung Experimental Forest, Kyonggi Province. The plantations were established on a similar soil in 1927, and included Larix decidua, Pinus strobus, and Thuja occidentalis. Ten soil samples within each plantation were taken during an entire growing season (May 2~Oct. 30, 1994). Mean daily nitrogen mineralization rates during 45-day in situ soil incubations were significantly different among species and incubation dates. Growing season nitrogen mineralization also differed significantly among species and ranged from 47.7 mg N/kg soil for Larix decidua to 21.5 ma N/kg soil for Thuja occidentalis. Growing season nitrification differed significantly among species and comprised from 93% to 100% of the total growing season nitrogen mineralized. We speculated that organic matter contents and quality might control nitrogen mineralization and nitrification in these soils.

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잣나무와 일본잎갈나무 수지구의 출현형태 (Appearance Pattern of Resin Canals in Pinus koraiensis and Larix kaempferi)

  • 김남훈;권성민
    • Journal of the Korean Wood Science and Technology
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    • 제34권1호
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    • pp.1-6
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    • 2006
  • 국내에 가장 많이 조림된 수종이고 중요한 국산 목재자원인 잣나무와 일본잎갈나무 두 수종의 재질특성을 구명하기 위하여 수지구와 에피델리얼세포의 수간내 변이성을 조사하였다. 그 결과, 두 수종 간에 수직수지구의 수와 그 수의 방사방향 변이성에 차이가 있었다. 일본잎갈나무의 수평수지구의 직경 및 에피델리얼세포 수도 방사방향으로 변이성을 나타냈다. 즉 미성숙재부와 성숙재부간에 수지구와 에피델리얼 세포의 출현특성이 차이가 있었다. 결론적으로, 잣나무와 일본잎갈나무에 있어서 수지구와 에피델리얼세포의 출현특성을 성숙재부와 미성숙재부로 구분하는 재질지표로 이용할 수 있을 것으로 생각하였다.

지리산산(智異山産) 일본 잎갈나무재(材)와 포플러재(材)의 단면별(斷面別) 평형함수율(平衡含水率)(EMC) 측정치(測定値)와 그 상관성(相關性) (Correlation between Determining Values of Sectional Equilibrium Moisture Contents of Larix leptolepis and Populus euramericana I - 476 grown in Mt. Jiri)

  • 황증;문창국
    • 한국산림과학회지
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    • 제59권1호
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    • pp.63-66
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    • 1983
  • 일본잎갈나무(Larix leptolepis)오 포플러(Populus euamerieana I-476)에 대(對)하여 각(各) 함수율(含水率)을 각단면별(各斷面別) 전건법(全乾法)에 의(依)한 측정치(測定値)와 Electric Moisture Meter(Kett-M8A) 측정치(測定値)와 계산추정치간(計算推定値間)이 상관성(相關性)과 그 신뢰성(信賴性)을 조사(調査)하여 본바 일본잎갈나무재(材)에 있어서는 전건측정치(全乾測定値), Moisture Meter측정치(測定値), 계산추정식간(計算推定値間)에 모든 방향(方向)에 1~5% 수준(水準)의 높은 상관성(相關性)을 보였으나 포플러재(材)에 있어서는 전건측정치(全乾測定値)와 Moisture meter측정치간(測定値間)에 상관성(相關性)은 인정(認定)되나 여지(餘地)에서는 유의의(有意義)한 상관성(相關性)을 인정(認定)할 수 없었다.

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북한 소나무과 나무의 생태와 자연사 (Ecology and Natural History of North Korean Pinaceae)

  • 공우석
    • 환경영향평가
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    • 제15권5호
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    • pp.323-337
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    • 2006
  • This work discussed the species composition, phylogeny, spatio-temporal distribution, ecology and natural history of North Korean Pinaceae or pine tree family, which seems to be important to maintain nature and ecosystem in the Korean Peninsula. Out of five genera and sixteen species of Pinaceae of the Korean Peninsula, North Korea contains four genera and eleven species of Pinaceae, including Pinus densilflora, P. koraiensis, P. pumila, Picea jezoensis, P. koraiensis, P. koraiensis var. koraiensis, P. pungsanensis, Larix gmelini, L. gmelinii var. olgensis, Abies holophylla and A. nephrolepis. In terms of phylogeny Pinus is closely related to Picea, and followed by Larix. Abies is close to Tsuga which only occur at Ullung Island. Distributional pattern of North Korean Pinaceae can be classified into four types; three species of nation-wide montane type i.e., Pinus densilflora, P. koraiensis and Abies holophylla, four species of central and northern subalpine type, i.e., Pinus pumila, Picea koraiensis, Larix gmelini and Abies nephrolepis, one nation-wide subalpine type, Picea jezoensis, and three species disjunctive to north type, i.e., Picea koraiensis var. koraiensis, P. pungsanensis, and Larix gmelinii var. olgensis. Pinaceae species occurring on the alpine and subalpine belts of North Korea, such as Pinus koraiensis, P. pumila, Picea jezoensis, P. koraiensis, P. koraiensis var. koraiensis, P. pungsanensis, Larix gmelini, L. gmelinii var. olgensis and A. nephrolepis are considered as the glacial descendant from the boreal region. Those species might have migrated from the north during the Pleistocene glacial epochs in search of favourable condition, and since the Holocene period they survived on the hostile alpine and subalpine environments, in which they are more competitive than warmth-tolerant temperate vegetation. Certain species, such as Picea pungsanensis, is segregated on the isolated mountains since the Pleistocene period, and forced to adapt to local environment, and eventually became an endemic species of North Korea. Recent rapid global warming trend especially in northern high mountains of North Korea could cause an unfavourable environment for the survival of cold-tolerant Pinaceae of the alpine and subalpine belts. Pinus densiflora, which is occurring on the montane belt might faced with difficulties due to both the deforestation and the outbreak of insect-borne disease, such as Bursaphelenchus xylophilus.

일본잎갈나무, 물박달나무, 밤나무 세포내강의 액체이동 (Capillary Flow in Different Cells of Larix Kaempferi, Betula Davurica, Castanea crenata)

  • 전수경
    • 한국가구학회지
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    • 제28권1호
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    • pp.88-93
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    • 2017
  • A study was carried out to observe the 1% aqueous safranine solution flow speed in longitudinal and radial directions of softwood Larix kaempferi (Lamb.)Carriere, diffuse-porous wood Betula davurica Pall.. and ring-porouswood Castanea crenata S.etZ. In radial direction, ray cells and in longitudinal direction, tracheids, vessel and wood fiber were considered for the measurement of liquid penetration speed at less than 12% moisture contents (MC). The length, lumen diameter, pit diameter, end wall pit diameter and the numbers of end wall pits determined for the flow rate. The liquid flow in the those cells was captured via video and the capillary flow rate in the ones were measured. Vessel in hardwood species and tracheids in softwood was found to facilitate prime role in longitudinal penetration. Anatomical features like the length and diameter, end-wall pit numbers of ray parenchyma were found also responsible fluid flow differences. On the other hand, vessel and fiber structure affected the longitudinal flow of liquids. Therefore, the average liquid penetration depth in longitudinal tracheids of Larix kaempferi was found the highest among all cells considered in Betula davurica and Castanea crenata, In radial direction, ray parenchyma of Larix kaempferi was found the highest depth and the one of Betula davurica was the lowest. The solution was penetrated lowest depth in the wood fiber of Castanea crenata. The large vessel of Castanea crenata was found the lowest depth among the vessels. The solutin was penetrated to the wood fiber of Betula davurica higher than the one of Castanea crenata.