• 한국해양공학회지
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• 제36권5호
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• pp.326-339
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• 2022

Recently, not only Korea but also the world has been suffering from problems related to coastal erosion. The hard defense method has been primarily used as a countermeasure against erosion. However, this method is expensive and has environmental implications. Hence, interest in other alternative methods, such as the eco-friendly vegetation method, is increasing. In this study, we aim to analyze the hydraulic characteristic of submerged rigid vegetation according to the cross-sectional change through a hydraulic experiment and numerical simulation. From the hydraulic experiment, the reflection coefficient, transmission coefficient, and energy dissipation coefficient were analyzed according to the density, width, and multi-row arrangement of the vegetation zone. From numerical simulations, the flow field, vorticity distribution, turbulence distribution, and wave distribution around the vegetation zone were analyzed according to the crest depth, width, density, and multi-row arrangement distance of the vegetation zone. The hydraulic experiment results suggest that the transmission coefficient decreased as the density and width of the vegetation zone increased, and the multi-row arrangement condition did not affect the hydraulic characteristics significantly. Moreover, the numerical simulations showed that as the crest depth decreased, the width and density of vegetation increased along with vorticity and turbulence intensity, resulting in increased wave height attenuation performance. Additionally, there was no significant difference in vorticity, turbulence intensity, and wave height attenuation performance based on the multi-row arrangement distance. Overall, in the case of submerged rigid vegetation, the wave energy attenuation performance increased as the density and width of the vegetation zone increased and crest depth decreased. However, the multi-row arrangement condition did not affect the wave energy attenuation performance significantly.

• 한국측량학회지
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• 제23권4호
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• pp.393-399
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• 2005

식생은 700nm근처에서 명확한 흡수파장대와 반사파장대를 갖고 있으므로 그 반사율의 차이가 상당히 크다. 이러한 식생의 흡수 및 반사파장대에 착안하여 식생에 관한 리모트센싱 기법을 실행하기 위하여 많은 식생지수가 연구되어지고 있다. 현재, 일반적으로 많이 사용되고 있는 식생지수로는 정규식생지수(NDVI)와 수직식생지수(PVI)가 있다. 일반적으로 식생의 활력도를 나타내는 것은 증산속도나 이산화탄소 소비량 그리고 클로로필농도등 이지만 주로 클로로필농도를 이용한다. NDVI나 PVI을 구하는데 이용되는 적색파장대는 클로로필의 흡광작용이 강하므로 클로로필 농도를 파악하는데도 유효하다. 특히 NDVI는 개략적인 식생상황을 파악하는데 주로 사용되기 때문에 초기조사에 많이 이용되고 있다. 그러나 이러한 식생지수는 활력도와 식생피복에 관한 정보가 혼합되어 있기 때문에 활력도와 식생피복간의 중복이 없는 독자적인 파장대에 패하여 모니터링을 할 필요가 있다. 지금까지 많은 식생지수는 식생의 활력과 식생피복이 혼재되어 있어서 함께 평가하였으나 본 연구에서는 활력도와 식생피복율을 분리평가하기 위하여 잔디를 이용한 실험을 행하여 분리 평가의 효용성을 강조하고자 하였다. 따라서 분광반사특성을 이용하여 식생지수를 평가한 결과 식생의 활력과 피복을 분리하여 평가하는 것이 바람직하다고 생각된다.

• 한국생태학회:학술대회논문집
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• 한국생태학회 2002년도 VIII 세계생태학대회
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• pp.71-77
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• 2002

For landscape ecological management of the isolated forestlands in Incheon city located in the western tip of South Korea, the forest vegetation of Mt. Cheolma was classified phytosciologically and mapped out its spatial distribution at a scale of 1:5,000. Characteristics of forest landscape structures were discussed in terms of the number and size of patches obtained by analyzing vegetation map. Units to manage the forest vegetation were categorized into eighteen communities, seventeen groups, and sixteen subgroups. Landscape elements were classified into five types: secondary vegetation, introduced vegetation for forestry (IVF), introduced vegetation for agriculture (IVA), and other elements. Two hundred and ninety-three forest landscape patches covers 443.3ha of which IVF accounted for 316.8ha(71.5%), the largest portion, secondary vegetation for f01.2ha(22.8%), IVA for 6.2ha(1.4%), and others for 19.1ha(4.3%). The ratio of natural forest elements of 31.9% showed that this area was mainly comprised of artificially introduced vegetation, such as Robinia pseudoacacia plantation and Pinus rigida plantation. Forest landscape patches have a mean area of 4.5ha, a density of 66.1/100ha, and a diversity index of 0.87. It was estimated that differentiation of patches recognized in community level would be related to human interference and those in subordinate level to natural processes.

• The Korean Journal of Ecology
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• 제25권4호
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• pp.205-211
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• 2002

For landscape ecological management of the isolated forestlands in Incheon city located in the western tip of South Korea, the forest vegetation of Mt. Cheolma was classified phytosciologically and mapped out its spatial distribution at a scale of 1:5,000. Characteristics of forest landscape structures were discussed in terms of the number and size of patches obtained by analy zing vegetation map. Units to manage the forest vegetation were categorized into eighteen communities, seventeen groups, and sixteen subgroups. Landscape elements were classified into five types: secondary vegetation, introduced vegetation for forestry (IVF), introduced vegetation for agriculture (IVA), and other elements. Two hundred and ninety-three forest landscape patches covers 443.3ha, of which IVF accounted for 316.8ha(71.5$\%$), the largest portion, secondary vegetation for 101.2ha(22.8$\%$), IVA for 6.2ha(1.4$\%$), and others for 19.1ha(4.3$\%$). The ratio of natural forest elements of 31.9$\%$ showed that this area was mainly comprised of artificially introduced vegetation, such as Robinia pseudoacacia plantation and Pinus rigida plantation. Forest landscape patches have a mean area of 4.5ha, a density of 66.1/100ha, and a diversity index of 0.87. It was estimated that differentiation of patches recognized in community level would be related to human interference and those in subordinate level to natural processes.

• 한국수자원학회논문집
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• 제56권1호
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• pp.23-34
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• 2023

본 연구에서는 실내실험과 수치모의를 통해 식생대에서의 소류사 이동 및 하도 변화를 분석하였다. 실내시험에서 식생대의 영향을 검토하기 위해 아크릴 봉으로 제작한 인공 식생대를 실험수로에 설치하였으며, 유량 조건을 조정하여 유량변화에 따른 식생대에서의 소류사 이동 및 하도 변화를 검토하였다. 다음으로 실내실험과 동일한 조건을 2차원 수치 모형인 Nays2D모형에 적용하여 수치모의를 수행하고, 그 결과를 실내실험 결과와 비교하여 수치모형의 적용성을 검토하였다. 마지막으로 적용성을 검토한 수치모형을 적용하여 식생밀도의 변화에 따른 소류사 이동 및 하도의 변화를 검토하였다. 실내실험과 수치모형을 적용하여 유량변화에 따른 식생대에서의 소류사 이동 및 하도 변화를 검토한 결과, 두 적용 방법의 결과가 유사하게 나타났다. 유량이 증가함에 따라 상류에서 유입된 소류사가 식생대 내부에 퇴적되었으며, 식생대 반대편에는 흐름이 집중되어 침식이 발생하였다. 또한 시간이 지날수록 하류방향으로 침식범위가 증가하였다. 식생밀도의 변화에 따른 소류사 이동 및 하도의 변화를 검토한 결과, 식생대의 식생밀도가 증가할수록 상류에서 유입된 소류사가 식생대 내부에 퇴적되었다. 또한 식생밀도의 증가로 인하여 흐름이 식생대의 반대편으로 집중되어 식생대 반대편 하도의 침식이 발생하였다.

• Journal of Ecology and Environment
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• 제41권1호
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• pp.1-8
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• 2017

Background: Though the biomass of floral vegetation in understory plant communities in a forested ecosystem only accounts for less than 1% of the total biomass of a forest, they contain most of the floral resources of a forest. The diversity of understory honey plants determines visitation rate of pollinators such as honey bee (Apis mellifera) as they provide rich food resources. Since the flower visitation and foraging activity of pollinators lead to the provision of pollination service, it also means the enhancement of plant-pollinator relationship. Therefore, an appropriate management scheme for understory vegetation is essential in order to conserve pollinator population that is decreasing due to habitat destruction and disease infection. This research examined the diversity of understory honey plant and studied how it is related to environmental variables such as (1) canopy density, (2) horizontal heterogeneity of canopy surface height, (3) slope gradient, and (4) distance from roads. Vegetation survey data of 39 plots of mixed forests in Chuncheon, Korea, were used, and possible management practices for understory vegetation were suggested. Results: This study found that 113 species among 141 species of honey plant of the forests were classified as understory vegetation. Also, the understory honey plant diversity is significantly positively correlated with distance from the nearest road and horizontal heterogeneity of canopy surface height and negatively correlated with canopy density. Conclusions: The diversity of understory honey plant vegetation is correlated to vegetation structure and human impact. In order to enhance the diversity of understory honey plant, management of density and height of canopy is necessary. This study suggests that improved diversity of canopy cover through thinning of overstory vegetation can increase the diversity of understory honey plant species.

• 국제초고층학회논문집
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• 제3권4호
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• pp.273-278
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• 2014

Green roof's performance in reducing stormwater runoff has been reported by numerous studies. Nonetheless, the roles of low growing vegetation in influencing stormwater runoff reduction on green roofs have been greatly overlooked. This paper describes an experiment investigating the influence of low growing vegetation in the reduction of tropical stormwater runoff on extensive green roofs. Three types of locally occurring native vegetation and one non-native Sedum species were selected (fern, herb, grass and succulent) for the experiment. Stormwater runoff reduction performance from different low growing species was done by measuring excess water runoff from the simulated green roof modules. The results show significant differences in stormwater runoff reduction from different types of vegetation. Fern was the most effective in reducing stormwater runoff, followed by herb, Sedum and grass. Vegetative characters that are found to attribute towards the performance of stormwater runoff are rooting density, structure, density, leaf type, and vegetation biomass.

• 한국환경복원기술학회지
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• 제21권5호
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• pp.81-96
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• 2018

The purpose of this study is to analyze the characteristics of vegetation changes and structures in the buffer green zone of Sihwa Industrial Complex and propose environmental, ecological and multi-functional vegetation management directions. The density of the Pinus thunbergii decreased from $23.1trees/100m^2$ in 2006 to $9.6trees/100m^2$ in 2017 due to the influence of thinning works. Its green volume increased from $0.97m^3/m^2$ to $2.02m^3/m^2$, contributing to the improvement of the atmospheric environment and promotion of biodiversity. The density of deciduous broad-leaved trees at the top maintained at $18{\sim}21trees/100m^2$. In the areas where the understory vegetation was removed, Pueraria lobata spread as an invasive plant and disturbed the forest. In the areas where the understory vegetation was not removed, various native plant species including the Rhus javanica and Celtis sinensis were introduced and contributed to the development of a forest in a multiple structure. There was a concern with the spread of Robinia pseudoacacia which developed into understory vegetation in Pinus thunbergii forest and some canopy forest. The study proposed vegetation management directions for the back, top and front side according to the physical structure of large-scale buffer green zone formed in a long linear form and the usage characteristics of adjacent land.

• Journal of Forest and Environmental Science
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• 제38권3호
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• pp.174-183
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• 2022

The study aims to examine population indices of mature trees in Jebel Elgarrie forest, Blue Nile State, Sudan. We used remote sensing techniques to stratify the forest into vegetation classes depending on tree density. We distributed 97 circular sample plots (0.1 ha) proportionally to the area of the vegetation classes. In each sample plot we identified, counted and recorded all mature trees (DBH ≥10 cm). We calculated frequency, density, abundance, richness, evenness and diversity for each species and we drew abundance rank curve of mature trees. We used One-Way ANOVA to test for differences (α=0.05) in mean density (No./ha) of mature trees between vegetation classes. Results revealed that the forest was conveniently sub-divided into high density (C1), medium density (C2), low density (C3) and bare farm land (C4) classes. We identified fifteen tree species that belong to 10 families and 14 genera. Combretaceae and Fabaceae were the common families while Anogeissus leiocarpa was the most frequently occurring species. While species diversity varied between vegetation classes, diversity of the forest as a whole is low. While mean density of mature trees in C1, C2, C3 and C4 it was 100, 74, 10, and 0, respectively, it was 54 for the whole forest indicating low stocking, Following One-Way ANOVA, multiple comparisons revealed significant differences in mean density of mature trees between C1 & C3 and C2 & C3. The study provided empirical results on population indices of mature tree species, which would be of importance for successful management and conservation of the forest.

• 한국수자원학회논문집
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• 제46권9호
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• pp.909-919
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• 2013

본 연구에서는 실내실험을 통하여 식생의 변화에 따른 하도의 수리학적특성, 저수로의 변화, 사주의 거동, 하안의 안정성 등을 정량적으로 파악하였다. 실내실험은 기존에 인공식생 대신에 수로에서 실제식생인 알팔파를 성장시켜서 수행하였다. 식생대에서는 유속이 매우 느리며, 저수로의 이동이 감소하였다. 2중 퓨리에 해석 결과, 교호사주의 특성을 나타낸 1-1모드의 진폭이 지배적이지만, 시간이 증가하면서 복렬사주의 특성을 나타내는 2-2와 2-3모드의 진폭이 증가하였다. 식생에 의하여 저수로가 고착화 되어 하도의 안정성이 증가하고, 하도 내 사주의 이동속도는 감소하지만, 하상이 불규칙하게 변하면서, 사주의 수는 증가하였다. 식생의 밀도가 증감함에 따라 하안의 안정성은 증가하였다. 식생의 밀도가 증가함에 따라 유사의 유출량과 유출량의 변동성이 감소하였다. 또한 망상화 강도는 감소하지만, 하도의 상관계수와 하상의 기복지수(BRI)는 증가하는 특성을 보여주었다.