• Title/Summary/Keyword: forest age

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Effects of Socioeconomic Factors and Forest Environments on Demand for Rural Residential Development (농촌 주거지 개발 수요에 대한 사회경제적 요인 및 산림환경의 영향 분석)

  • Lee, Yohan;Ji, Seongtae
    • Environmental and Resource Economics Review
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    • v.25 no.2
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    • pp.199-228
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    • 2016
  • This study investigates the effects of economic factors and forest environments on rural residential area development in seven north central states of the U.S. by focusing on the relative importance of not only economic factors but also forest environments by forest type as core drivers of residential development. An empirical model of locations and magnitudes of population changes since 1950 in the north central region is first constructed, and then a panel model with fixed effects for counties is used to explain population growth by age group over time at the county level. Then a set of three equations is estimated for three major age groups, and a cross-sectional model is estimated for the last time period that regresses county-level environmental amenity variables on fixed effects coefficients for counties. Finally, an equation explaining changes in rural housing density is estimated. The results imply that immigrant age is a key factor influencing the choice of the place of residence and that the effects of environmental amenity factors on population growth and subsequent housing development in a county vary according to the age group.

Physical and Mechanical Properties of Korean Red Pine Wood from Different Growth Sites and Correlations between Them (생장지역별 소나무재의 물리적·역학적 특성과 상호 상관관계)

  • Han, Yeonjung;Lee, Hyun-Mi;Eom, Chang-Deuk
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.5
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    • pp.695-704
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    • 2016
  • Physical and mechanical properties of Korean red pine wood grown in Anmyeon-do, Taean-gun, Chungcheongnam-do and Sogwang-ri, Uljin-gun, Gyeongsangbuk-do, Korea were measured and each relationships between them were analyzed. The ring width and latewood proportion along radial axis in Korean red pine at two-regions were measured by collecting the growth core of stands with age class V and IX. The ring width in Korean red pine at two-regions decreased with increasing cambium age. The average ring widths in age class V and IX in Anmyeon-do and Sogwang-ri were 2.865 mm, 1.705 mm, 4.764 mm, and 2.228 mm, respectively. The ring widths in Anmyeon-do were measured from 23% to 40% smaller than Sogwang-ri. The latewood proportion was negatively related with the ring width of Korean red pine at two-regions. The relationship between physical and mechanical properties of specimens for compressive and bending strength tests were analyzed with simple regression analysis. The relationship between latewood proportion and oven-dry density were positive and statistically significant. The relationship between latewood proportion and mechanical properties was slightly positive and not statistically significant, except the specimens for bending strength test of Anmyeon-do. The relationship between oven-dry density and mechanical properties was positive. It was just statistically significant in the specimens of Sogwang-ri. The compressive and bending strengths of Anmyeon-do and Sogwang-ri were 51.3 MPa, 80.5 MPa, 37.7 MPa, and 63.7 MPa, respectively. The strength difference between two-regions was determined to due to difference of ring width and latewood proportion by age class.

Effects of Region and Age on Nut Quality of Major Chestnut Cultivars (Castanea spp.) cultivated in the Central Region of Korea (우리나라 중부지역 주요 밤 재배품종의 지역 및 수령에 따른 과실품질)

  • Kim, Mahn-Jo;Lee, Uk;Park, Yun Mi;Hwang, Suk-In
    • Journal of Korean Society of Forest Science
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    • v.100 no.4
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    • pp.616-622
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    • 2011
  • This study was conducted to investigate the effects of region and age on nut quality of major chestnut cultivars (Castanea spp.) cultivated in the central region of Korea to provide basic data for nut quality control and processing of postharvest. In the survey of by regions and ages, Buyeo and 'Hyogo57' showed the highest value by regions and cultivars, respectively. Also, there were statistically significant differences among regions and cultivars in the value of soluble solid content and kernel hardness. In the soluble solid content, Gongju showed the highest value among regions, and 'Tsukuba' among cultivars was the highest, 20.5%. Cheongyang showed the highest value of kernel hardness among regions, and 'Tanzawa' among cultivars showed the lowest value of kernel hardness, $8.75kg/cm^2$. In 'Tanzawa', 'Okkwang' and 'Tsukuba', soluble solid content and kernel hardness showed statistically significant differences according to age, but no correlation with age.

Analysis of the Timber Harvesting Potential of the Garisan Leading Forest Management Complex in Hongcheon (홍천 가리산 선도산림경영단지의 목재생산 잠재량 분석)

  • Young-Hwan Kim;Dong-ho Lee;Min-jae Cho;Jin-Woo Park
    • Journal of Korean Society of Forest Science
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    • v.112 no.4
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    • pp.523-529
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    • 2023
  • The aim of this study was to analyze the potential for timber harvesting in the Hongchoen Garisan Leading Forest Management Complex in the national forests, and to suggest an optimal target yield for sustainable timber harvesting. The potential for timber harvesting was assessed by analyzing the area available for timber harvesting using GIS spatial analysis, but excluding areas with a slope of more than 40° (topographical constraints), areas within 30 m on both sides of streams (environmental constraints), and areas more than 300 m away from forest roads (technical constraints). The analysis identified 3,298 ha (49%) of the total complex area of 6,679 ha as available for timber harvesting, yielding a potential harvesting volume of 608,613 m3. In the case of coniferous plantations, the potential harvesting volume was 409,721 m3, which was a very high level that accounted for 67.3% of the total. We also conducted an optimization analysis to minimize the differences in area between age classes, while maintaining sustainable timber harvesting for the next 50 years. An annual average of 41.9 ha (7,988 m3) was determined to be the optimal timber yield, and in this case, it was possible to convert the age class structure to a more stable structure after 50 years.

Vegetation Structure Analysis of Urban Forest -The Case of Namsan in Kyungju- (도시림의 식생구조분석 -경주 남산을 중심으로-)

  • 이영경;최송현
    • Journal of the Korean Institute of Landscape Architecture
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    • v.28 no.3
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    • pp.13-24
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    • 2000
  • In urban area, urban forests work as an ecological center that mitigates the environmental pollution of the area. In order to maintain the ecological function of a forest, the management method should be established based on ht through investigation of the vegetation structure of the forest. In this study, the vegetation structure of Namsan in Kyungju area was investigated in order to study the ecological value of Namsan and to suggest a desirable management alternative. 21 plots were selected as survey areas. Using the TWINSPAN technique, the forest of Namsan was classified into four communities: Quercus serrata community(I), Castanea crenata-Q. serrata-Q. mongolica community(II), Pinus densiflora community(III) and P. densiflora-P. rigida-Robinia pseudoacacia community(IV). The survey results were summarized by five: 1) the distribution of vegetation showed 2) P. densiflora was the absolutely dominant species in Namsan, 3) number of the average species was 12.6$^{\circ}$$\pm$3.1, 4) number of individual was 131.1$^{\circ}$$\pm$47.8 per a plot(100$m^2$), 5) the results of annual ring analysis revealed that the age of P. densiflora in Namsan was about 3 0$^{\circ}$~60$^{\circ}$years old. From the above results, it was found out that the forest has two problems. One thing is maintenance of P.densiflora against succession, another is artificial forest dispersion. The problems of Namsan forest management will be solved with further studies related.

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Assessment of Naturalness by Application of new Technique (새로운 기법(技法)을 적용(適用)한 자연도(自然度) 평가(評價))

  • Lee, Young Geun;Lee, Don Koo;Lee, Byung Doo
    • Journal of Korean Society of Forest Science
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    • v.90 no.4
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    • pp.488-494
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    • 2001
  • This study was conducted to investigate forest ecosystem assessment which were widely used in Germany and Austria. The study area, Mt. Teawha, is located at Kwangju, Kyunggi-Do province. The methodology of this study considered the following factors. First forest types were classified accoding to species composition and age of tree layer. Naturalness, diversity and rerenees of each forest type were classified into 5 level. Finally, the forest types were assessed by synthesizing those 3 factors. Qurecus mongolica- and valley forest type over 300m was classified as naturalness 4 and Qurecus accustima, Quercus accusitima and Q. variabilis were as naturalness 3. The plantation types on the lower slope showed the level of naturlness 1 or 2. Diversity was similer to naturalness. But indices were different from each other. In the case of Larix leptolepsis plantations, naturalness indicated 1, while diversity showed 3. The valley forest type, wet forest and forest edge were classified into rare forest type. It was concluded that this method could be more efficient method comparing with existing method for assessment of naturality and thereby could contribute for biodiversity conservation in Korea.

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Optimum Use of Forest Biomass Generated from the National Forest Management Operation (Part 1) - Study of Characteristics of Kraft Pulps Made from Single Wood Species - (숲가꾸기 산물의 최적용도 개발을 위한 연구 (제1보) - 단일 수종으로 제조된 크라프트 펄프의 특성 연구 -)

  • Park, Hyun-Jin;Kim, Chul-Hwan;Lee, Jee-Young;Lee, Gyeong-Sun;Lee, Ji-Young;Sheikh, M.I.;Sim, Sung-Woong;Yim, Su-Jin;Lee, Young-Min;Ahn, Byung-Il
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.44 no.5
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    • pp.63-71
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    • 2012
  • This study was carried out to investigate pulping properties of the forest biomass arising from the national forest management operation. The forest biomass was collected and classified into many groups according to their species and age. After the chips were made from the forest biomass, the measurement of chip size and chemical analysis were performed. To make the pulps from the forest biomass, the kraft pulping was applied and thereafter the physical and optical properties of kraft pulps were measured. The pulp fibers from the forest biomass had the similar mean fiber length, but their properties became different according to wood species and ages. Differently from the other species, kraft pulps from chestnut wood had the highest kappa number. Acacia, paulownia and chestnut woods made kraft pulps with lower tensile strength and brightness than the others. It could be concluded that acacia, paulownia and chestnut woods must be screened out in order to make a good quality of kraft pulps while being collected during Forest Management Operation.

Physical and Mechanical Properties of Quercus serrata according to Stand Characteristics in Southern Region of Korea (남부지역 졸참나무의 임분 특성에 따른 물리·역학적 특성)

  • Won, Kyung-Rok;Hong, Nam-Euy;Lee, Kwang-Soo;Jung, Soo-Yung;Yoo, Byung-Oh;Park, Young-Bae;Chong, Song-Ho;Byeon, Hee-Seop
    • Journal of the Korean Wood Science and Technology
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    • v.42 no.6
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    • pp.659-665
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    • 2014
  • Wood properties are affected by environmental factors such as soil and climate change. There were close relationships between mechanical properties and stand characteristics for Quercus serrata stands in Gyeongsangnam-do Province, Jeollanam-do Province and Je-ju island. Both compression and shear strengths of woods showed a negative correlation with diameter at breast height (DBH) and the number of tree per hector, while they are positively related with with tree age, altitude, and drainage. The annual ring width was also negatively correlated with tree age, altitude, drainage, DBH, and tree height. However, anatomical characteristics of wood did not show much variation depending on the provincial regions. These results brought a conclusion that Quercus serrata in southern region could be useful forest resources for the utilization of wood.

Growth Performance of Pinus densiflora Introduced from Six Provenances of Japan at Chungju, Korea (충주에 식재한 일본 6개 산지 소나무의 생장)

  • Kwon, Yong-Rak;Ryu, Keun-Ok;Kim, In-Sik;Lee, Kap Yeon
    • Journal of Korean Society of Forest Science
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    • v.95 no.3
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    • pp.250-255
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    • 2006
  • Pinus densiflora is a dominant conifer species in Korea and also distributed in regions of Japan and eastern China. Success in the establishment and productivity of forest tree plantation is largely determined by selection of species and seed source. The provenance tests of Pinus densiflora in Korea are underway. However, the information of the growth performance of Japanese and Chinese provenances are insufficient. Therefore, this study was conducted to evaluate the growth performance of Pinus densiflora Japanese provenances. Data were collected from a provenance trial including established by Korea Forest Research Institude at Chungju in 1970. Six Japanese provenances ($31^{\circ}90^{\prime}{\sim}40^{\circ} 27^{\prime}$ in latitude and $128^{\circ}47^{\prime}{\sim}141^{\circ}80^{\prime}$ in longitude) were included in this trial. Pyeongchang provenance at Kangwon province in Korea was used for reference provenance. At nursery stage, the height and diameter at root collar of six Japanese provenances were smaller than those of Pyeongchang provenance. Among Japanese provenances, Kasahara provenance showed higher growth performance than those of others. The provenance rankings of growth performance were fluctuated until age 11. However, the growth performance of Japanese provenances showed higher than those of reference provenance after age 17. Kirishima-yama provenance showed best growth performance. Simple correlation analysis was conducted to investigate the geographic factors affecting growth performance. The height growth showed negative corelation with latitude of seed origin. Generally, Japanese provenences of Pinus densiflora were well adapted and grown in Chungju. However, it was suggested that further studies on other sites need to generalize the results of this study.

Estimation of Site Index Equation for Pinus densiflora at Mt. Osu Region using Schnute Growth Function (Schnute 생장함수를 이용한 오서산지역 소나무림의 지위지수 추정)

  • Pyo, Jung-Kee;Lee, Young-Jin;Son, Yeong-Mo;Lee, Kyeong-Hak;Moon, Hyun-Shik
    • Journal of agriculture & life science
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    • v.43 no.4
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    • pp.9-14
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    • 2009
  • The purpose of this study was to estimate height growth pattern and to derive site index equation for Pinus densiflora grown at Mt. Osu region, Chungnam. A total of 21 repre - sentative trees from the established temporary plots around Boryeng and Cheongyang regions were destructively sampled to measure diameter, height, volume growth per 1-year interval by using of DTRS- 2000 measurement instrument. The Schnute growth function was select ed for height growth prediction using 181 height-age paired observations and derived anamorphic base age invariant site index curves (base index age 30 years). The fitted index and the asymptotic value of Schnute model indicated both 0.96 and 10.8 meter, respectively. The results suggested in this study could be very useful to understand the height growth pattern and productivity of the site quality on Pinus densiflora grown at Mt. Osu region, Chungnam.