• Title/Summary/Keyword: Dierssen

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Forest Community Classification of Dodeokbong and Baekwunbong in Daejeon (대전 도덕봉과 백운봉의 산림군락 분류)

  • 김효정;이미정;지윤의;안승만;이규석;송호경
    • Korean Journal of Environmental Biology
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    • v.20 no.3
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    • pp.216-223
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    • 2002
  • This study was carried out to classify forest vegetation community of Dodeokbong and Baekwunbong in Gyeryongsan. Employing the releve method of Dierssen, 89 plots were sampled. Forest community was classified into Quercus mongolica community, Quercus serrata community, Quercus variabitis community, Pinus densiflora community, Carpinus laxiflora community, and Pinus rigida-Pinus thunbergii community. Quereus mongolica community was found in high altitude and steep area, Quercus serrata community in relatively low altitude and steep slope area, and Quercus variabilis in southern arid and low area compared with Quercus mongolica community. Pinus densiflora community is present in relatively high altitude and narrow arid ridge area. And, Carpinus laxiflora community is mainly distributed in southern valley area. Pinus rigida-Pinus thunbergii community is planted community.

Characteristics of Behavior of Steel Sheet Pile installed by Vibratory Pile Driver (진동타입기에 의해 시공되는 강널말뚝의 거동특성)

  • Lee, Seung Hyun;Kim, Byoung Il;Kim, Zu Cheol;Kim, Jeong Hwan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.1C
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    • pp.27-35
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    • 2010
  • Instrumented steel sheet piles being driven by vibratory pile driver were installed in granular soil deposit and behaviors of the sheet piles were investigated. One of the instrumented steel sheet pile was installed without clutch and the other was installed with clutch. Sheet pile with clutch means that of installed in connection with pre-installed sheet pile. Penetration rates of sheet piles measured from depth measuring drum has shown that interlock friction had great effect on penetration speed of sheet pile. Clutch friction shows irregular distribution along the depths of penetration and its magnitude was estimated as 19.1kN/m. According to the accelerations obtained from accelerometer, it was seen that steel sheet pile behaviored nearly as a rigid body. Efficiency factor of an isolated sheet pile was 0.42 and that of the connected sheet pile was 0.71. Shapes of dynamic load transfer curves obtained from analysis of measuring devices was similar to those suggested by Dierssen.

Effects of Forest Eire on Herb Layer Development and Chemical Properties of Soil (산화가 초본층의 발샐 및 토양의 화학적 특성에 미친 영향)

  • 박관수;이미정;송호경
    • Korean Journal of Environment and Ecology
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    • v.16 no.2
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    • pp.141-148
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    • 2002
  • This study was carried out to estimate the effect of forest fire on herb layer development and chemical properties of soil. The forest fire was in April 2000 in Pinus rigida(softwood) and Robinia pseudoacacia(hardwood) dominant forests at Gaejoksan, Daejeon. Vegetation studies were in the two communities and herb layer development study was in July using dominance of Dierssen. The coverage of herb layer was higher in the burned area than in the unburned area in the two study communities. There was no different herb layer species number between the burned and unburned areas, but there was different herb layer species number between the two communities. Soil samples were collected at 0~10cm and 10~20cm soil depths from the unburned and burned sites after 3 days and 8 months of forest fire. There was no forest floor in burned site, but unburned site has the forest floor of 1.5cm thick. There were no significant differences in soil organic matter, total N, available P, exchangeable K, Ca, Na, and Mg, and CEC, pH in all soil depth, between unburned and burned sites after 3 days of forest fire and between burned site after 3 days and 8 months of forest fire, except in organic matter in 10~20cm soil depth in hardwood sites and in exchangeable Ca in the 10~20cm soil depth, and in Mg in the two soil depths in hardwood sites. It seems to be that forest fire had not changed the chemical soil properties in this study.

The Study of vegetation Structure and Soil Characteristics in Koelreuteria paniculata Communities of Anmyondo and Gunhung-Myon, Taean-Gun (안면도 및 태안군 근흥면 모감주나무군락의 식생구조 및 토양특성에 관한 연구)

  • Song, Ho-Kyung;Park, Kwan-Soo;Lee, Sun;Lee, Mi-Jung;Ji, Yoon-Eui
    • Korean Journal of Environmental Biology
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    • v.18 no.1
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    • pp.69-75
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    • 2000
  • The vegetation structure and soil characteristics in Koelreuteria paniculata communities of Taean-Gun and Anmyondo were studied. The Koelreuteria paniculata community in Anmyondo had two vegetation layers, lower-tree and herb layers, but the Koelreuteria paniculata community in Anmyondo had three vegetation layers, subtree, shrub, and herb layers. Also the Koelreuteria paniculata was only the species of subtree layers in the Koelreuteria paniculata community of Anmyondo, but the subtree layer in the Koelreuteria paniculata community of Taean-Gun consisted of Pinus thunbergii, Cornus walteri, Celtis jessoensis, Celtis sinensis, and Evodia danielii. The soil organic matter, total N, available P, CEC, and exchangeable K, Ca, Mg, and Na concentrations were greater in the two Koelreuteria paniculata community than in the adjacent forest. The range of soil pH in the two Koelreuteria paniculata communities were 6.3-7.0, but those in adjacent forests were 4.7-5.5. [Dierssen scale, Vegetation classification, Forest soil] .

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