• Title/Summary/Keyword: forest age

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Growth Performance of Pinus strobus at Four Plantations in Korea (스트로브잣나무의 조림지역에 따른 산지별 생장반응)

  • Choi, Hyung-Soon;Ryu, Keun-Ok;Kwon, Hae-Yun;Jeon, Du-Sik;Kim, Kyong-Hwan;Ahn, Chan-Gi;Ahn, Young-Hwan
    • Korean Journal of Breeding Science
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    • v.40 no.4
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    • pp.377-386
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    • 2008
  • The growth performance of Eastern white pine (Pinus storbus L.) was studied with six provenances in four plantations. All growth performances were significantly different among provenances and plantations. The most outstanding source in volume growth at age 39 is North Carolina in all plantations and this trends had been started from four years old seedlings. In plantations, the growth is best in ChunCheon plantation while that is worst in GunPo plantation. The Effect of plantations was thought to be larger than that of provenances growth of P. strobus. A pattern of growth by ages was different by among plantations and even ate age about 40, the growth was still vigorous. Annual precipitation, foggy days, altitude and sand contents in soil are positively correlated with growth and the correlations between by ages were very high.

Effect of Tree Age and Active Alkali on Kraft Pulping of White Jabon

  • Wistara, Nyoman J.;Carolina, Anne;Pulungan, Widya S.;Emil, Nadrah;Lee, Seung-Hwan;Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.5
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    • pp.566-577
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    • 2015
  • White Jabon (Anthocephalus cadamba Miq.) is one of the fast growing species in Indonesia and has the potential as the raw material for pulp and paper. In this research, 3, 5, and 7 years old White Jabon woods were pulped under different active alkali charge of 15%, 18%, 21%, 24%, and 27%, and its effect on delignification degree, kappa number, pulp yield, pulp viscosity, brightness, unbeaten freeness, and delignification selectivity was investigated. The results showed that tree age and active alkali concentration influenced the quality of pulp and pulping properties, except for that of unbeaten freeness. Delignification degree increased with increasing active alkali charge, and this brought about the decrease of pulp kappa number. The pulping yield tended to decrease below the Klason lignin of approximately 4%. Even though the 3 years old wood resulted in the highest brightness and highest delignification selectivity, the highest pulp viscosity was obtained with the 5 years old wood. The dominant fiber length of all wood ages was in the range of 1.2 - 2.0 mm. The 3 years old wood was considered to be the most promising raw material for kraft pulping in the view point of pulping properties, pulp quality and harvesting rotation.

An Analysis the Relationship between User characteristics by Forest Welfare Facilities: Focusing on Correspondence Analysis (산림복지시설별 이용객 특성과의 관계 분석: 대응분석을 중심으로)

  • Dong-Hoon Kim;Byung-Hoon Kang;Eun-Jee Lee;Hee-Ji Kang;Jeong-Hee Lee
    • Journal of Korean Society of Forest Science
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    • v.113 no.1
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    • pp.1-13
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    • 2024
  • This study used the results of the 2022 national survey of forest welfare facilities and space users conducted in the Republic of Korea to identify the associations and combination patterns among use of forest welfare facilities and various user characteristics. In addition, a correspondence analysis-namely, a categorical data analysis-was performed regarding four facilities: National Natural Recreation Forest, National Soopchewon, National Forest Trail, and National Healing Forest. The cross-analysis revealed highly significant differences (p < .001) in the age, household income per month, means of transportation, companion type, path to information acquisition, and purpose of visit among the users of forest welfare facilities. Moreover, the results of the correspondence analysis demonstrated that users of National Soopchewon and National Healing Forest were distinguished from users of the other forest welfare facilities based on demographic characteristics such as age and household income per month. In addition, the means of transportation of National Forest Trail users differed from that of users of the other forest welfare facilities. Moreover, users of National Soopchewon were associated with the type of public group visit, acquisition of information from the websites of related institutions and facilities and via online portals, and the purpose of participating in education and experiencing education programs. Therefore, the companion type, path to information acquisition, and purpose of visit on the part of users of National Soopchewon could be differentiated from those of users of other forest welfare facilities. The findings of this study revealed the associations and combinations among forest welfare facilities and the characteristics of users of such facilities, with the scope of utilization of the forest welfare facility user data being expanded via correspondence analysis.

Evaluation of Watershed Stability by the Forest Environmental and Stream Morphological Factors (산림환경 및 하천형태인자에 의한 유역안정성 평가)

  • Jung, Won-Ok;Ma, Ho-Seop
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.4 no.4
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    • pp.1-11
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    • 2001
  • This study was carried out to analyze the characteristics of forest environmental and stream morphological factors by using the quantification theory(I) for evaluation of the watershed stability. Present annual mean sediment yield of erosion control dams were investigated in 167 sites of erosion control dam constructed during 1986 to 1999 in Gyeongbuk. The results obtained from this study were summarized as follows; According to the coefficients of partial correlation, each factor affecting to sediment was shown in order of gravel contents, number of first streams order, number of total streams, length of total streams, forest type, length of main stream, parent rock, stand age, soil texture, stream order, slope gradient, soil depth and aspect. Descriptions of class I were as follow; Igneous rock of parent rock, hardwood stands of forest type, less than 20 year of stand age, less than 30cm of soil depth, sandy clay loam of soil texture, more than 41% of gravel contents, south~east of aspect, 2,501~3,500m of length of main stream, 21~25 of number of total streams, 5,501~10,000m of length of total streams, 3 or more than 4 of stream order, more than 16 of number of first stream orders and more than $31^{\circ}$ of slope gradient. Descriptions of class II were as follow; Metamorphic rock of parent rock, coniferous stands of forest type, more than 25 year of stand age, 31~40cm of soil depth, silt loam of soil texture, 11~20% of gravel contents, north~west of aspect, 2,501~3,500m of length of main stream, 16~20 of number of total streams, 3,501~5,500m of length of total streams, 3 of stream order, 11~15 of number of first stream orders and more than $31^{\circ}$ of slope gradient. Descriptions of class III were as follow; Sedimentary rock of parent rock, mixed stands of forest type, more than 25 year of stand age, more than 51cm of soil depth, silty clay loam of soil texture, less than 10% of gravel contents, south~west of aspect, less than 500m of length of main stream, less than 5 of number of total streams, less than 1,000m of length of total streams, less than 1 of stream order, less than 2 of number of first stream orders and less than $25^{\circ}$ of slope gradient. The prediction method of suitable site for erosion control dam divided into class I, II, and III for the convenience of use. The score of class I evaluated as a very unstable area was more than 8.4494. A score of class II was 8.4493 to 6.0452, it was evaluated as a moderate stable area, and class III was less than 6.0541, it was evaluated as a very stable area.

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A Pollen Analysis on the Environmental Changes during the Later Half of the Postglacial Age around the Basin of Onyang River, Asan (화분분석을 이용한 아산시 온양천 유역의 후빙기 후기 환경변화)

  • PARK, Ji-Hoon
    • Journal of The Geomorphological Association of Korea
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    • v.17 no.1
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    • pp.39-48
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    • 2010
  • This is a case study to research the environmental changes that occurred during the Latter Half of the postglacial age around the Basin of Onyang River in Asan, Korea. In line with this purpose, the author performed a pollen analysis and a radiocarbon dating on the deposits of alluvial fan around the upper Geumgok River, a tributary of Onyang River. Sampling point was at the altitude of about 67.5 meters, which belongs to the central zone of the cool temperate forest. The followings are the results of the study. The study area has passed through SC-I (the coniferous forest period in which Pinus was dominant), SC-II (the deciduous broad-leaved forest period in which Quercus and Castanea were dominant) and SC-III (the mixed conifer and deciduous broad-leaved forest period, in which Pinus, Quercus and Ulmus/Zelkova were dominant) respectively since about 3,000 yrB.P. SC-I period and SC-II period are presumed to be between about 3,000 and 2,000 yrB. P., and SC-III period to begin after 2,000 yrB.P. In comparison with the nationwide pollen zone during the postglacial age, SC-I and SC-II periods are contrasted with the R-IIIa zone and also the SC-III zone with the RIIIb zone. In addition, it is assumed that Pinus densiflora forest luxuriated there since 2,000 yrB.P. due to the destruction of forests, and that a lot of Fagopyrum pollen appeared; altogether, it was the so-called human interference period, from which forests began to be markedly destroyed. It is concluded that in those days inhabitants leaded agricultural life.

Studies on Guarantee Strategies of Overseas Timber Resources (해외(海外) 목재자원(木材資源) 확보(確保) 전략(戰略)에 관한 연구(硏究))

  • Woo, Jong-Choon;Won, Hyun-Kyu;Kim, Young-Sik
    • Journal of Forest and Environmental Science
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    • v.11 no.1
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    • pp.1-21
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    • 1995
  • This paper was aimed to find alternatives for coping spontaneously with the changing world forest resoures and international timber markets after UNCED in 1992. The guarantee of timber resources abroad in Korea is essential and the urgent subject, because about 90% of korean forest resources are specially under III age class and young, korean forest is in the step of improvement forestry. Therefore, some strategies were proposed for the stable guarantee of overseas timber resources.

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Analysis of the Final Cutting Ages in Quercus variabilis Coppice Forests (굴참나무 맹아갱신지의 벌기령 추정)

  • Park, Joon Hyung;Chung, Sang Hoon;Kim, Sun Hee;Kim, Hyungho;Lee, Sang Tae
    • Journal of Korean Society of Forest Science
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    • v.109 no.4
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    • pp.468-476
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    • 2020
  • we developed a stand density management diagram for Quercus variabilis in order to predict the final cutting ages of coppice forests based on management objectives. The sample data were classified into two groups: 603 data points for analysis and 113 data points for verification. Using these data, a stand density management diagram was constructed and a goodness-of-fit test was performed. The explanatory power (R2) of the constituent models for the stand density management diagram was 0.732 for the equivalent height curve and 0.990 for the equivalent diameter curve. According to the analysis of the final cutting age rangeof the highest production, the final cutting ages for 900 buds remaining per hectare was 42-44 years, and that for the 1,800 buds remaining per hectare was 38-42 years. With the third-grade log set as the production target, the final cutting age range with site index 16 and 14 was 25-28 years and 29-33 years, respectively. The results of this study provide baseline data for establishing a management plan for Q. variabilis coppice stands.

Analysis Methology of Detailed Stand Age Classes in Forest Type Map (임상도 작성시 정밀 영급분석기법 연구)

  • Kim, Jeong-Ho
    • Journal of Environmental Science International
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    • v.17 no.6
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    • pp.647-655
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    • 2008
  • The purpose of the study is to find the problems related to the current state of the stand age classes and the method of calculating it defined in the existing forest type map and propose the more accurate method of calculating the stand age classes. The object for the study was selected as the forest scattered around the Geesan village Paju city in Kyunggi province. For the accurate method of calculating the stand age classes, such items as, the type of actual vegetation, establishment of grid-type standard area scaled down at the level of the 5% of the actual area, the types, number, DBH and age of tree found by the plots, were investigated. It was found out actual vegetation was divided into the total 24 types and the 20 types of them belonged to the growing tree areas. As the plots, the 125 places(unit area: $400m^2$) were established the types of the trees found were distributed in the range where the minimum was 1 type, the maximum was 9, the mean was $4.4{\pm}1.5$, and the mode was 4 types. The number of the trees found was distributed in the range where the minimum was 17, the maximum was 125, the mean was $4.4{\pm}1.5$, and the mode was 70. In the DBH, the minimum was 6 cm, the maximum was 30 cm, the mean was 13 cm and the mode was 10 cm. As the result of measuring the age of the 5 trees corresponding to the value of the mode in DBH, selected among the dominant species by the plots, less than 20 years was 17 places, the 115 places were included in the range from 21 to 30 years, and more than 31 years was the 6 places.

Study on the Recognition of Forest-Official's and Stakeholders's Toward Improvement of Tree Cutting Permit System (입목벌채 허가제도 개선에 대한 벌채허가 담당자와 벌채 실행자의 인식조사)

  • Park, Kyung-Seok;Lee, Seong-Youn;Bae, Sang-Won;Kim, Min-Hee;Kim, Hyun-Sig;Baik, Kyung-Soo;An, Ki-Wan
    • Journal of Korean Society of Forest Science
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    • v.100 no.2
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    • pp.292-304
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    • 2011
  • The purpose of this study is to draw institutional implications for tree cutting permit system improvement in comparison with Korea and foreign countries (German, Japan). A survey about recognition of cutting system and cutting-invigorating factors for two groups in charge of work for cutting permit (forest-official) and cutting operation (forest owner, tree butcher, forestry association, and forestry corporation) was carried out. The survey provides basic information which is necessary to improve current cutting system. The result of analysis about both German and Japan's cutting system show that clear cutting area to hinder function of forests tends to decrease and flexible final age of maturity considering condition of regional forest not uniform cutting age were applied. As a result of German and Japan's cutting system review flexible cutting system on regional characteristics is used to manage for the purpose of forest regeneration. The survey result about awareness and invigorating factors of cutting system represents that only public official group said final age of pine tree (3.13) and cedar (3.05) was proper and final age of other species of trees should have shortened. In matters of cutover area, current standard is less than 5ha per a felling area and the largest total area limit is 30 ha, only tree butcher, forestry corporation said cutover area must expand. Invigorating factors of current cutting system are reinforcement of cutover area, facility support, enrichment of technical training, increase of equipment support, simplification of administrative procedures, and provision of various benefits. The reinforcement of technical training among them especially represents the statistical significance of the participants' differential recognition.

Population Structure, and Emergence and Growth Dynamics of Seedling, and Spatial Distribution of Dendropanax morbifera Lev.(Araliaceae) (황칠나무의 집단구조와 치수의 발생과 생육동태 및 공간분포)

  • 정재민
    • Korean Journal of Plant Resources
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    • v.11 no.3
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    • pp.345-352
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    • 1998
  • A Korean endemic and evergreen small tree ' Dendropanax morbifera $L_{EV}$.(Araliaceae)' is a component of evergreen forest and mainly idstributein sourthern region and islands in Korea. A local population of D. morbifera which is located between evergreen and deciduous forest within 50m x 50m quadrate was investigated to ascertain the change of population structure, emergence and growth dynamics of seedlings and saplings, and pattern of spatial distribution by the temproal and spatial expansion of population . The result of analysis of population structure by Importnace Value(IV), evergreen forest showed a high species diversity of evergreen tree species such as Cinnamomum japonicum, Machilus japonica, Neolitsea serica, Daphniphyllum macropodum, Ligustrum japonicum, and etc, in middle and under story than in upper story where Camelia japonica and Quercus acuta were dominant. And in conterminous deciduous fores, the major component of evergreen forest in this region, Camellia japonica, Quercus acuta, evergreen tree of Lauraceae and etc. were abundant in only under story. IV of D. morbifera differed from among three story. In comparative analysis of emergence and growth dynamics of D. morbifera seedlings and saplings between evergreen and deciduous forest, emergece and density of seedlings were significantly greater in evergreen than in deciduous forest, and growth of height and basal diameter of seedlings and saplings were slightly larger in evergreen than in deciduous forest. The spatial distribution patterns by Moristia's index mapping of indivuduals using a lattice method of XY axis within this population showed that seedlings(age up to 2 years) and saplings (age>2 years and height<1m) both evergreen and deciduous forest were more or less aggregated apart from mature trees, and thougth intermediate trees(height>1m and dbh<10cm) had a aggregated distribution pattern, mature trees(dbh>10cm were uniform. In conclusion , the expansion of D. morbfera population from evergreen to deciduous forest accompanied with a mumber of evergreen woody species, and also, emergence and recruitment, and growth of seedlings were greatly influenced moisture and canopy by around community structure.

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