• Journal of Ocean Engineering and Technology
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• v.21 no.5
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• pp.18-24
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• 2007

The environmental value of coastal vegetation has been widely recognized. Coastal vegetation such as reed forests and seaweed performs several useful functions, including maintaining water quality, supporting fish (and, thus, fisheries), protecting beaches and land from wave attack, stabilizing sea beds and providing scenic value. However, studies on the physical and numerical process of wave propagation, sediment transport and bathymetric change are few and far between compared to those on the hydrodynamic roles of coastal vegetation. In general, vegetation flourishing along the coastal areas attenuates the incident waves through momentum exchange between stagnated water mass in the vegetated area and rapid mass in the un-vegetated area. This study develops a numerical model for describing the wave attenuation and sediment transport in a wave channel in a vegetation area. By comparing these results, the effects of vegetation properties, wave properties and model parameters are clarified.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.1
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• pp.28-34
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• 2002

This study was carried out to analyze the effects of elapsed years and physical properties on invaded vegetation of forest road slope. For the study, 8 forest roads in Asan-si of Chungcheongnam-do were selected and 15 factors that might influence on vegetation invasion were analyzed. In generally, vegetation coverage of slope have increased with the elapsed years. But invasion species have decreased in the cut-slope and increased in fill-slope. There was no significant correlation between rate of vegetation coverage and elapsed years, but rate of vegetation coverage was strongly related with slope aspect. And the species of invasion vegetation affected mostly by the elapsed years and slope aspect among the physical properties.

• The Korean Journal of Ecology
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• v.21 no.6
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• pp.779-789
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• 1998

The forest vegetation established on Mt. Hwangryung located in Pusan, southern Korea was analyzed through phytosociological procedure. Vegetation of the study area was categorized into 14 communities, 16 groups, and 13 subgroups. Vegetation units obtained from such an analysis were shown in a detailed vegetation map (scale 1:5,000). Ecological characteristics of each vegetation unit were discussed on the basis of the principle of restoration ecology. From those results, it was confirmed that some introduced vegetation under excessive artificial interference was in unstable state and then ecological restoration was needed. On the other hand, ecological information and management systems to maintain the urban forest as ecologically healthy state were developed using GIS.

• Journal of Environmental Science International
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• v.27 no.11
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• pp.983-989
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• 2018

The real-time monitoring of surface vegetation is essential for the management of droughts, vegetation growth, and water resources. The availability of land cover maps based on remotely collected data makes the monitoring of surface vegetation easier. The vegetation index in an area is likely to be proportional to meteorological elements there such as air temperature and precipitation. This study investigated relationship between vegetation index based on Moderate Resolution Image Spectroradiometer (MODIS) and ground-measured meteorological elements at the Yongdam catchment station. To do this, 16-day averaged data were used. It was found that the vegetation index is well correlated to air temperature but poorly correlated to precipitation. The study provides some intuition and guidelines for the study of the droughts and ecologies in the future.

• Journal of Korean Society of Forest Science
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• v.109 no.3
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• pp.249-258
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• 2020

The purpose of this study examined the succession by vegetation type after forest ecosystem restoration in the Baramjae area. Vegetation of the Baramjae area was classified using a survey of 81 sites from May to October 2019. The vegetation type was classified as Pinus densiflora community group with both Quercus mongolica community and P. densiflora typical community. The group unit was further classified as the Quercus dentata typical subgroup, Salix koreensis subgroup, and Q. mongolica typical subgroup. Such as Q. mongolica, Quercus variavilis in vegetation unit 1, Q. mongolica, Q. dentata in vegetation unit 2, P. densiflora in vegetation unit 3 and S. koreensis in vegetation unit 4 were shown a high importance value. The difference in species by vertical layer is explained by sere. Based on the vegetation type classification system, Detrended Correspondence Analysis was conducted to observe the trend of succession. Since restoration, vegetation unit 1 and vegetation unit 2 were considered to have developed the most extensive vegetation. In vegetation unit 2 and vegetation unit 4, many of the species found were in the early vegetation development in S. koreensis subgroup. Accordingly, vegetation in the Baramjae area can be categorized as a stepwise succession.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.1
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• pp.72-82
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• 2015

We constructed greenhouse gas (GHG) and air pollution (AP) integrated sink/emission inventories and evaluated the environmental value for the vegetation sector in Seoul during year 2010. The data of vegetation, classified into four sectors of cultivated land, forest land, park and street tree, were obtained from Statistics Korea and Seoul City. Based on the previous studies, only $CO_2$ was chosen as GHG sink by vegetation. $NO_2$ and $SO_2$ were chosen as AP sink by vegetation, while isoprene, monoterpene, other VOC (OVOC) and NH3 were chosen as AP emission from vegetation. Estimation methodology and sink/emission factors were gathered from reports and published literatures. Estimated GHG sink by vegetation during year 2010 was 12,987,173 $tonCO_{2eq}$, of which approximately 1/4 was from pure vegetation and the remaining 3/4 from vegetation soil. AP sink and emission were estimated to be 23,309 tonAP and 2,629,797 tonAP, respectively. The analysis by administrative districts in Seoul revealed that among 25 districts, Seocho-gu, Nowon-gu, Eunpyeong-gu, Gwanak-gu and Gangbuk-gu were the major districts in GHG and AP sink/emission inventories for vegetation sector. Environmental value of vegetation as a function of GHG and AP sink, was estimated as 800 billion won, corresponding to 5% of the total cost of the forest land in Korea evaluated as a public function.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.3
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• pp.107-116
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• 2011

One of the major factors which increase urban temperature is roads. This paper is aimed to investigate the effect of urban roadside vegetation on the road surface temperature. For this, surface temperature was measured at 18 spots using the thermal imaging camera in terms of road components including use of roadside land use, roadway, sidewalk, roadside vegetation and vegetation median barrier. The size of the roadside vegetation and related urban road characteristics were also measured. In terms of the effect of roadside vegetation on a decrease in road surface temperature, the roadside land use as a green area or open space was the highest, followed by the size of vegetation median barrier and the size of roadside vegetation. Besides road surroundings, an increase in the green zone such as roadside vegetation and median strip vegetation has a significant impact on lowering road surface temperature. Therefore, a good solution for reducing urban heat island effects would be to increase the area of roadside vegetation and green areas along roads.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.2
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• pp.28-37
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• 2008

In this study, we perform land surface monitoring of NDVI (Normalized Difference Vegetation Index) variation by using remote sensing data during 1999-2005 over North Korea, which can't easily access to measure directly land surface characteristics due to one of the world's most closed societies. North Korea forest region has most abundant forest vegetation - so called Lungs of Korea in the Korea peninsula. NDVI represents vegetation activity used in many similar studies. In this study, we detect vegetation variation and analysis factors of the change over North Korea. By using variation of NDVI, we can infer that effect of drought over North Korea, and reduced vegetation indices by typhoon in North Korea. Land surface type except barren ground with decreased NDVI value is considered as when North Korea region was suffering from drought and typhoon effects, which show lower than mean of 7-year NDVI value. Especially, in recently, the food production of North Korea with political and economical issues can be inferred indirectly these trends by using estimated output data from this study.

• Journal of Ecology and Environment
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• v.41 no.2
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• pp.34-44
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• 2017

Background: Monitoring terrestrial vegetation cover condition is important to evaluate its current condition and to identify potential vulnerabilities. Due to simplicity and low cost, point intercept method has been widely used in evaluating grassland surface and quantifying cover conditions. Field-based digital photography method is gaining popularity for the purpose of cover estimate, as it can reduce field time and enable additional analysis in the future. However, the caveats and uncertainty among field-based vegetation cover estimation methods is not well known, especially across a wide range of cover conditions. We compared cover estimates from point intercept and digital photography methods with varying sampling intensities (25, 49, and 100 points within an image), across 61 transects in typical steppe, forest steppe, and desert steppe in central Mongolia. We classified three photosynthetic groups of cover important to grassland ecosystem functioning: photosynthetic vegetation, non-photosynthetic vegetation, and bare soil. We also acquired normalized difference vegetation index from satellite image comparison with the field-based cover. Results: Photosynthetic vegetation estimates by point intercept method were correlated with normalized difference vegetation index, with improvement when non-photosynthetic vegetation was combined. For digital photography method, photosynthetic and non-photosynthetic vegetation estimates showed no correlation with normalized difference vegetation index, but combining of both showed moderate and significant correlation, which slightly increased with greater sampling intensity. Conclusions: Results imply that varying greenness is playing an important role in classification accuracy confusion. We suggest adopting measures to reduce observer bias and better distinguishing greenness levels in combination with multispectral indices to improve estimates on dry matter.

• Journal of Ocean Engineering and Technology
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• v.36 no.5
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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.