• Title/Summary/Keyword: vegetation

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Utilizing Concept of Vegetation Freeboard Equivalence in River Restoration

  • Lee, Jong-Seok;Julien, Pierre Y.
    • International Journal of Contents
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    • v.8 no.3
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    • pp.34-41
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    • 2012
  • The concept of vegetation freeboard equivalence (VFE) is presented from the comparison between the rise in stage with/without vegetation and the freeboard height under design discharge conditions. In South Korea, the freeboard height of large, medium and small rivers is defined as a function of river discharge. Two models are used for this analysis of flood stage with and without vegetation: the 1-D model HEC-RAS and the 2-D model RMA-2. Both models are applied to three river study sites of the Geum River in South Korea as representative sites for a large, a medium and a small river. The analysis shows that without vegetation, both models provide comparable results and the calculated results are in very good agreement with the design configuration. The vegetation effects on the medium river are less significant, and the freeboard is adequate to contain the rise in stage from the added floodplain vegetation in large rivers. The concept of vegetation freeboard equivalence is therefore useful for the analysis of flood river stages after the restoration of channels with increased floodplain vegetation.

Effects of Microtopography on the Development of Riparian Vegetation in Stream Corridors (하천통로에서 미세 지형 발달이 하천 식생에 미치는 영향)

  • 정경진;김동엽
    • Journal of the Korean Institute of Landscape Architecture
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    • v.27 no.4
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    • pp.39-49
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    • 1999
  • Urban streams have, recently, been straightened and widened to alleviate flooding problem. As a result, the stream have been modified inadvertently for ecological functions and microtopography. In this study, we investigated riparian vegetation and microtopography of the tributaries of Han River before and after the monsoon rain in summer. The purpose of this study was to relate the stream microtopography to the distribution of riparian vegetation. The stream microtopography was investigated for its scale and pattern. Vegetation was investigated from 131 plots by Braun-Blanquet method. The distribution of riparian vegetation was significantly correlated with the stream microtopography. Various herbaceous species occurred at stream bank slop, high terrace and channel side. However, at channel side and concave part of terrace where soils were in high moisture level, only a few wetland species were dominated. The complexity of the microtopography in the stream corridors led to heterogeneous riparian vegetation. The vegetation showed more stability against flooding at the stream corridors with natural and complex microtopography than at the urban-type stream corridors with simple topographical features. The results showed that the development of riparian vegetation was influenced by the changes in microtopography, which was primarily determined by the shape and characteristics of channel. It seemed that a close-to-nature river system would be restored more readily with an understanding of microtopographical features affecting the distribution of riparian vegetation.

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Comparative Analysis of the Multispectral Vegetation Indices and the Radar Vegetation Index

  • Kim, Yong-Hyun;Oh, Jae-Hong;Kim, Yong-Il
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.6
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    • pp.607-615
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    • 2014
  • RVI (Radar Vegetation Index) has shown some promise in the vegetation fields, but its relationship with MVI (Multispectral Vegetation Index) is not known in the context of various land covers. Presented herein is a comparative analysis of the MVI values derived from the LANDSAT-8 and RVI values originating from the RADARSAT-2 quad-polarimetric SAR (Synthetic Aperture Radar) data. Among the various multispectral vegetation indices, NDVI (Normalized Difference Vegetation Index) and SAVI (Soil Adjusted Vegetation Index) were used for comparison with RVI. Four land covers (urban, forest, water, and paddy field) were compared, and the patterns were investigated. The experiment results demonstrated that the RVI patterns of the four land covers are very similar to those of NDVI and SAVI. Thus, during bad weather conditions and at night, the RVI data could serve as an alternative to the MVI data in various application fields.

Vegetation Structure arid Management Planning of the Sansung Nature Park, Cheonju (전주시 산성자연공원의 식생구조 및 관리대책)

  • 최만봉;이규완;오구균
    • Journal of the Korean Institute of Landscape Architecture
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    • v.18 no.1
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    • pp.41-51
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    • 1990
  • This study was executed to investigate the vegetation structure and to propose the vegetation management proposals of the Sansung Nature Park at Cheonju City and the results were as fellows. 1. A damage of vegetation and soil surface around the Namgosa was taken place up to 100m by picnic 2. Pinus rigida forest covered 36.1% of the total area(152.6ha) and total afforested vegetation covered 43.5%, respectively. P. denstflora comm. covered 28.4% arid Carpinus laxiflora Comm. as a climax vegetation in temerate zone covered 0.3%, respectively. 3. 6, 7 and 8 of the degree of human disturbance of vegetation covered 45.3%, 26.6% and 21.4%, respectively and resulted in low quality of naturalness. 4. Physical and chemical properties of soil were pour at high elevation and were poor severely in and around the Namgosa due to human disturbance. 5. Plant community were under rapid succession and had unvalanced structure and heterogeneous composition of species. Rapid vegetational succession from Pinus densiflora and Pf. rigida to Carpinus laxifora, Quercus spp. and Robinina pseudo-acacia were taken place.6. The speeies of Raunkiaer's frequency class I as of high frequency class were Pinus dunsiflora, Carpinus alxiflora, Quercus mmongolica, Sorbus alnifolia, Prunrs sargintii, Rhododendron yedoense, Stephanandra incisa and Lespedeza maxinowiczii. 7. Vegetational management proposals were made for three vegetation zones ; Historic landscape restoration and preservation zone, Afforested vegetation zone, Native vegetation conservation zone and recommanded native species for landcape planting.

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Phytosociological Study on the Vegetation of Daehuksan Island (대흑산도 식생에 대한 식물사회학적 연구)

  • Kim, Chul-Soo;Jang, Yoon-Seok
    • The Korean Journal of Ecology
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    • v.12 no.3
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    • pp.145-160
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    • 1989
  • Daehuksan Island (125°23'-125° 28' E and 34°37'-34°42' N, ca 19.7㎢) in the southwestern part of Mokpo, Korea, is a part of the Dadohae National Marine Park. Most of the actual vegetation of the island is substitutional vegetation under various human impact such as grazing, cutting for firewood. And natural vegetation is partially distributed in the tutelary shrine forests, deep valleys, etc. During 1987, phytosociological investigation of this was carried out on the basis of Braum-Blanguet's method. The forest vegetation was classified into 1 association and 7 communities, Camellia japonica, Machilus thunbergii, Ardisio-Castanopsietum sieboldii, Daphniphyllum macropodum-Quercus acuta, Pyrrosia lingua-Pinus densiflora. Rhododendron mucronulatum-Pinus thunbergii, Carpinus coreana, and Psedosasa japonica community. Grassland vegetation was classified into Gleichenia japonica, Gleichenia dichotoma, Arundinella hirta-Miscanthus sinensis, Artemisia princeps var. orientalis. Imperata cylindrica var. koenii Artemisia princeps var. orientalis-Pennisetum alpecuroides, Carex boottiana, and salt marsh vegetation. Thypa orientalis, Spergularia marina, Phragmites communis, Carex scabrifolia, and Triglochin maritimum community. Based on them, the actual vegetation map was made in 1:50,000 scale.

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Reducing Effect of Traffic Noise Soundproof Facilities (방음시설의 소음저감효과에 관한 연구)

  • Jeon, Gi-Seong;Park, Young-Ho
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.3 no.1
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    • pp.20-26
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    • 2000
  • In order to propose the design and installation information of vegetation belt, field investigation were carried out in the noise pollution control facilities of highway and the streets of a city for two years(1998~1999), and field tests were performed to analyze the noise attenuation effect of them. The noise pollution control facilities were generally classified into three types (noise barrier and vegetation belt type, mounding and vegetation belt type, vegetation belt type only). Most soundproof facilities were proved the noise reduction effects. But according to width, height, structure, auditory distance and planting forms of them, difference of noise reduction effects were investigated. The soundproof facility was suitable the mounding and vegetation belt type in the consideration of road environment, and the installation standard of vegetation was estimated that the width of vegetation was at least 20m and the length of that was 2 times in the distance from noise source.

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Numerical modeling of Atmosphere - Surface interaction considering Vegetation Canopy (식물계를 고려한 지표-대기 상호작용의 수치모의)

  • 이화운;이순환
    • Journal of Environmental Science International
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    • v.3 no.1
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    • pp.17-29
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    • 1994
  • An one dimensional atmosphere-vegetation interaction model is developed to discuss of the effect of vegetation on heat flux in mesoscale planetary boundary layer. The canopy model was a coupled system of three balance equations of energy, moisture at ground surface and energy state of canopy with three independent variables of $T_f$(foliage temperature), $T_g$(ground temperature) and $q_g$(ground specific humidity). The model was verified by comparative study with OSUID(Oregon State University One Dimensional Model) proved in HYPEX-MOBHLY experiment. As the result, both vegetation and soil characteristics can be emphasized as an important factor iii the analysis of heat flux in the boundary layer. From the numerical experiments, following heat flux characteristics are clearly founded simulation. The larger shielding factor(vegetation) increase of $T_f$ while decrease $T_g$. because vegetation cut solar radiation to ground. Vegetation, the increase of roughness and resistance, increase of sensible heat flux in foliage while decrease the latent heat flux in the foliage.

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Fundamental Studies for District Planning in Natural Park (자연공원의 용도지구계획을 위한 기초적 연구)

  • 배병호
    • Journal of the Korean Institute of Landscape Architecture
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    • v.19 no.3
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    • pp.27-40
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    • 1991
  • For the establishment of district planning in natural parks, vegetationin the most significant point. Consequently, district plan should be made basically under phytosociological investigations. The purpose of this paper is to conserve vegetation in the district planning at natural park(Nam Han San Sung provincial natural park). The result of vegetation survey are as follows : As an actual vegetation 13 communities are recognized. Those are Quercus mongolica-Carpinus laxiflora community, Quercus mongolica-Rhododendron schlippenbachii community, Quercus serrate community, Betula platyphylla var. Japonica community, Quercus dentata community, Quercus mongolica-Pnuus densiflora community, Quercus acutissima community, Robinia pseudo-acacia community, Alnus hirsuta community, Castanea crenata community, Quercus variabilis community, Pinus densiflora community, Pinus rigida community, weed community on cultivated land(Form land), Larix leptolepis reforested land, cut over area and non-vegetation area. The grade of vegetation naturalness was divided into five degrees by characteristics of actual vegetation. I intended to make zoning plan for protection of vegetation with a special attention to the grade of vegetation naturalness and I discussed the necessity of the improvement of existing district plan. District plan was proposed as Fig. 5.

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Community Structure of forest vegetation in Mt. Bislsan (비슬산(琵瑟山) 산림식생(山林植生)의 군락구조(群落構造))

  • Lee, Jung-Hyo;Suh, Seung-Hee;Hong, Sung-Cheon
    • Current Research on Agriculture and Life Sciences
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    • v.23
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    • pp.9-18
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    • 2005
  • Vegetation composition and structure of forest community at Mt. Bislsan, Dalseung-Gun, Daegu in Korea, were studied using a qualitative with a quantitative approach and its vegetation types and various ecological characteristics such as the importance values, species diversity of the major component species analyzed. The forest vegetation were classified into 2 community group, 14 community, 6 group, and total of 18 vegetation units. Pinus densiflora distributed mainly from lower at the sea level, while Quercus mongolica tended to distributed upper altitude in Physiognomical vegetation. the species diversity values showed mostly 0.8 and Quercus dentata, Quercus serrato and Cornus controversa Community and so on highly showed to 1.0 and 1.1. According to the results of importance value analysis, the I.V. of pinus densiflora and Quercus mongolica highly showed in the tree and subtree layer, and Rhododendron mucronulatum and Lindera obtusiloba and so on highly showed in the shrub.

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FLOW-VEGETATION-SEDIMENT INTERACTION

  • Dittrich Andreas;Jarvela Juha
    • Water Engineering Research
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    • v.6 no.3
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    • pp.123-130
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    • 2005
  • A good understanding of the interaction between flow, vegetation, and sediment is required for successful river restoration and sustainable flood management. The purpose of this paper is to provide a summary of available methods to determine flow resistance of natural rivers with vegetation, and discuss the influence of vegetation on erosion and sedimentation processes. Recently, significant advances have been made, but the effects of vegetation on flow and sediment dynamics are still not fully understood. Possible solutions to close the gaps in the current knowledge are suggested, with special focus directed to the determination of the interactive width between main channel and vegetated floodplains, the flow resistance of flexible vegetation with and without leaves, and the flow over submerged vegetation with low water depth.

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