• Title/Summary/Keyword: forest structure

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Analyzing Research Trends in Forest Watersheds Using the Vosviewer Program (VOSviewer 프로그램을 이용한 산림유역 관련 연구동향 분석)

  • Ji-Eun Lee;Rhee-Hwa Yoo;Min-Jae Cho
    • Journal of the Korean Society of Industry Convergence
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    • v.26 no.6_3
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    • pp.1183-1195
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    • 2023
  • In this study, we collected and analyzed domestic and international studies related to watersheds in the forest sector. Keyword co-occurrence analysis was conducted using the VOSviewer program to identify the research areas of domestic and international studies and the network structure to compare research trends. As a result, the number of research articles in international watershed-related studies showed an overall increasing trend, and the research areas were diverse and located close to each other, indicating that many convergence studies were conducted. On the other hand, the number of papers in domestic watershed-related studies seems to have stagnated overall from the past to the present, and the research areas are mainly focused on forest disasters and hydrology, with limited interdisciplinary convergence studies. In addition, in both domestic and international studies, watersheds are currently mentioned as research sites rather than management or analysis units in the forest sector. It is important to actively promote interdisciplinary research in Korea to provide a scientific and balanced basis for watershed-level forest management planning.

Community Structure of Natural Monument Forest (Forest of Japanese Torreyas in Pyeongdae-ri, Jeju and Subtropical Forest of Nabeup-ri, Jeju) in Jeju-do (제주도 천연기념물 수림지(제주 평대리 비자나무 숲과 제주 납읍리 난대림)의 군집구조)

  • Jeong Eun Lee;Yo Seob Hwang;Ho Jin Kim;Ju Heung Lee;Chung Weon Yun
    • Journal of Korean Society of Forest Science
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    • v.112 no.4
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    • pp.393-404
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    • 2023
  • The Natural Monument Forest (NMF) is a form of natural and cultural heritage that has symbolized the harmony between nature and culture in Korea for a long time. Recently, the NMF has deteriorated due to industrialization and reckless city expansion. Given this situation, it is necessary to preserve and manage the ecosystem of the NMF through preferential research regarding the forest community structure. Accordingly, this study sought to identify the community structure by analyzing the vegetation classification, stratum structure,and species diversity using vegetation data collected from the Forest of Japanese Torreyas in Pyeongdae-ri, Jeju and the Subtropical Forest of Nabeup-ri, Jeju. The results classified the forest vegetation as a Litsea japonica community group divided into two communities: a Torreya nuciferacommunity and a Quercus glauca community. The T. nuciferacommunity was subdivided into the Idesia polycarpa group and Dryopteris erythrosora group, while the Q. glauca community was subdivided into the Mercurialis leiocarpa group and Arachniodes aristata group. The T. nucifera species showed the highest level of importance in vegetation units 1 (Litsea japonicacommunity group-Torreya nucifera community-Idesia polycarpa group) and 2 (Litsea japonica community group-Torreya nucifera community-Dryopteris erythrosora group), whereas Q. glauca showed the highest level of importance in vegetation units 3 (Litsea japonica community group-Quercus glauca community-Mercurialis leiocarpa group) and 4 (Litsea japonica community group-Quercus glauca community-Arachniodes aristata group). In terms of the species diversity, vegetation units 1, 2, 3, and 4 had 2.866, 2.716, 2.222, and 2.326 species, respectively. These findings suggest that it is necessary to prepare a differentiated management plan for each vegetation unit.

Species Diversity of Arbuscular Mycorrhizal Fungi Community Depending on Environmental Conditions of Forest Soils (산림(山林)의 토양환경(土壤環境) 조건(條件)에 따른 수지상(樹枝狀) 균근(菌根)(AM)균(菌) 집단(集團)의 종(種) 다양성(多樣性))

  • Koo, Chang-Duck
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.3 no.1
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    • pp.70-79
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    • 2000
  • Arbuscular mycorrhizal(AM) fungi have significant role for ecosystem structure and function. They are the major component of forest soil ecosystems and critically important for water and nutrient cycling in the system. To understand the ecology of AM fungi the fungal spores were collected, identified and counted in forest soils under various climatic and edaphic conditions. In relation to soil depth 90% of AM fungi spores and mycorrhizas distributed within 15cm soil depth. Number of spores per $100m{\ell}$ forest soil volume was 5 to 36 spores from 1 to 3 fungal species. AM fungal species diversity was higher in warmer climates, and more moist and fertile soils. The most frequently found species were Gigaspora decipiens irrespective of soil moisture and Gi. gigantea irrespective of soil fertility. In the Jeju island the soils of Cryptomeria japonica plantations and Miscanthus sinensis var. purpurascens meadow had more AM spores than the other soils. We suggest AM fungi be considered as keystones species when restoring a disturbed forest ecosystem.

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Introduction of Wooden Kagome Structure to the Furniture Design

  • Chung, Woo-Yang;Xu, Hui-Lan
    • Journal of the Korea Furniture Society
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    • v.21 no.3
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    • pp.248-252
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    • 2010
  • This study is carried out to introduce the concept of Kagome structure as the new trial for the furniture design and the feasibility of its utilization in furniture industry. Kagome means originally the two dimensional bamboo-basket woven pattern that is composed of interlaced triangles whose lattice points each have four neighboring points, which was used in traditional bamboo craft design like 'Jukbuin(bamboo-wife)'. Its unique truss structure has been widely used by many kinds of the domain of science and engineering in mechanical and architectural industry with some merits, i,e, material utilization efficiency and robust strength. Here we tried to introduce two dimensional and three dimensional form of Kagome which are supposed to be a furniture design elements. Authors think these Kagome design could be realized with domestic lumber of inferior properties. Both of them would be used as a decorative element or mechanical supporter in furniture design.

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Factors Affecting Z-direction Penetration of PVAm Solution into Paper (PVAm 용액의 종이 두께 방향 침투에 영향하는 인자들)

  • Choi, Do-Chim;Won, Jong Myoung;Cho, Byoung-Uk
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.47 no.5
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    • pp.104-111
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    • 2015
  • Factors influencing penetration of PVAm solution into paper during impregnation were investigated with ultrasonic Penetration Evenness Analyzer (PEA). Paper structure was varied by changing basis weight, freeness of pulp, calendering, and filler addition, and hydrophobicity of paper was varied by adding AKD. In addition, the viscosity of PVAm solution was varied by changing the concentration of PVAm solution. Important factors influencing penetration of PVAm solution into paper were found to be the pore structure and the hydrophobicity of paper, and the viscosity of PVAm solution. Pore structure of paper could be controlled by refining degree and filler addition and hydrophobicity of paper could be controlled by internal sizing. Denser structure of paper, higher hydrophobicity and higher liquid viscosity slowed down the penetration of PVAm solution into paper.

Effect of Fines Distribution on Press Dewatering and Physical Properties of Multi-ply Sheet

  • Lee, Hak-Lae;Youn, Hye-Jung;Kang, Tae-Young;Choi, Ik-Sun
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.40 no.5
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    • pp.36-41
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    • 2008
  • Multi-ply sheet forming has many advantages including the possibility of using wide range of materials in a given structure, lowering production cost, making higher grammage products and so on. But, incorrect structure of sheet makes flow resistance higher so that it shows poor dewatering in press section. One of major factors that affect sheet structure and dewatering property is fines content in each layer. We, therefore, examined the press dewatering of multi-ply sheet that has the different fines content in each layer and the effect of fines distribution on physical properties of sheet to find a technology for optimum utilization of raw materials. In case of two layered sheet, the sheet which was composed of layers with the different flow resistance showed higher dewatering rate than one which has the same flow resistance. And the more difference in fines content for layers existed, the more dewatering occurred. For three layered sheets, dewatering is mainly dependent on fines content of bottom layer. Strength properties were affected by dewatering degree and multi-ply sheet structure.

Comparison of Genetic Diversity and Population Structure of Kalopanax pictus (Araliaceae) and its Thornless Variant Using RAPD

  • Huh, Man-Kyu;Jung, Sang-Duk;Moon, Heung-Kyu;Kim, Sea-Hyun;Sung, Jung-Sook
    • Korean Journal of Medicinal Crop Science
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    • v.13 no.2
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    • pp.69-74
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    • 2005
  • Kalopanax pictus is a long-lived woody species mostly distributed in East Asia. K. pictus has been regarded as medically and ecologically important species in Korea. Thornless castor aralia variant, local name 'Cheongsong' is an endemic to Cheongsong province in Korea. Random amplified polymorphic DNA (RAPD) was used to investigate the genetic variation and structure of Korean populations of two species. A high level of genetic variation was found in six K. pictus populations. Twelve primers revealed 49 loci, of which 29 were polymorphic (59.2%). Nei's gene diversity for K.pictus and K. pictus variant were 0.119 and 0.098, respectively. Mean of genetic diversity in K. pictus was higher than average values for species with similar life history traits. The asexual and sexual reproduction, perennial habitat, and longevity are proposed as possible factors contributing to high genetic diversity. An indirect estimate of the number of migrants per generation (Nm=0.857) indicated that gene flow was not extensive among Korean populations of K.pictus. It is suggested that the isolation of geographical distance and reproductive isolation between K.pictus and K.pictus variant populations may have played roles in shaping the population structure of this species.

A Study on Architecture and Structure of Landscape Building in Remote Mountain Village - Focused on Southwestern Black Forest Area, Germany - (유럽 산간마을의 건축과 경관형성실태에 관한 연구 - 독일의 남서부지역 블랙 포레스트를 중심으로 -)

  • Chong, Geon-Chai
    • Journal of the Korean Institute of Rural Architecture
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    • v.21 no.3
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    • pp.41-48
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    • 2019
  • The purpose of this study is to understand whether the architecture of the mountain village conforms to the geography and local landscape, and become a unique scenic element. Also, the study is to grasp the status of the village landscape design elements. The methods and contents of the study were surveyed by field research with references in Biederbach community, an isolated mountain village in Southwestern Germany. The time frame for the survey research is July 2015. The contents of the study include the analysis of the village's landscape structure, architecture, and landscape design patterns. The following conclusions were reached through the above research process. First, the village landscape structure seen in the mid-distance view is the hilly scene of the alpine region, which houses the sloping terrain of Black Forest and surrounds the residential area with the grassland covered by the Black Forest. Second, the main elements of the town's landscape building are historical culture, traditional architecture, topology and nature, and artificial environmental design. Third, the landscape design utilizing the village's resources creates a sustainable community's residential environment.

Generation of DEM Data Under Forest Canopy Using Airborne Lidar

  • Woo Choong-Shik;Kim Tae-Guen;Shin Jung-Il;Lee Kyu-Sung
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.512-514
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    • 2005
  • Accurate DEM surface of forest floor is very important to extract any meaningful information regarding forest stand structure, such as tree heights, stand density, crown morphology, and biomass. In airborne lidar data processing, DEM data of forest floor is mostly generated by interpolating those elevation points obtained from last laser returns. In this study, we try to analyze the property of the last laser return under relatively dense forest canopy. Airborne laser data were obtained over the study area in relatively dense pine plantation forest. Two DEM data were generated by using all the points in the last laser returns and using only those points after removing non-ground points. From the preliminary analysis on these DEM data, we found that more than half of points among the last laser returns are actually hit from canopy, branches, and understory vegetation that should be removed before generating the surface DEM data.

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Simulation of Forest Succession in Kwangnung Experimental Forest with Gap Model (Gap 모델을 이용한 광릉삼림군락의 천이에 대한 모의 실험)

  • Han, You-Young;Park, Seung-Tai;Kim, Joon-Ho;Lee, Chang-Seok
    • The Korean Journal of Ecology
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    • v.19 no.6
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    • pp.499-506
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    • 1996
  • Forest stand development in Kwangnung Experimental Forest, Korea, was simulated with a forest succession gap model of the JABOWA/FORET type, in order to predict climax species and characterime the trend of community structure along the succession. The model runs for a period or 1, 000 yr and is based on the averaged successional characteristics of 50 forest plote with an individual size or 1/12 ha gap consisted of the 15 major tree species. The total bimass and leafarea index have arrived at a steady state since about 200 yr and these values are smaller than that or field survey. Carpinus cordata, C. laxiflora, Quercus mongolica and Q. serrata were epected to be climax species that represent about 86% or total biomass in later stage and these results coincided with the previous succession studies from field survey in the area.

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