• Korean Journal of Remote Sensing
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• v.17 no.2
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• pp.111-119
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• 2001

This study analyzes time variability of the normalized difference vegetation index (NDVI), the leaf area index (LAI) and surface temperature (Ts) estimated from AVHRR data collected from across the Korean peninsula from 1981 to 1994. In the present study, LAI defined as vegetation density, as a function of NDVI applied for the vegetation types and Ts defined by the split-window formulation of Becker and Li (1990) with emissivity of a function of NDVI, are used. Results of the inter-annual, intra-annual and intra-seasonal variabilities in Korea show: (1) Inter-annual variability of NDVI is generally larger in the southem and eastern parts of the peninsula than in the western part. This large variability results from the significant mean variation. (2) Inter-annual variability of Ts is larger in the areas of smaller NDVI. This result shows that the NDVI play a small role in emissivity. (3) Inter-annual variability of LAI is larger in the regions of higher elevation and urban areas. Changes in LAI are unlikely to be associated with NDVI changes. (4) Changes in NDVI and Ts are likely dominant in July and are relatively small in spring and fall. (5) Urban effect would be obvious on the time-varying properties of NDVI and Ts in Seoul and the northern part of Taejon, where NDVI decreases and Ts increases with a significant magnitude.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.6
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• pp.545-552
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• 2017

Aeolian dunes are typical sand dunes which are maintained and developed by interactions of earth surface, wind and vegetation. Developing a model which can predict the changing phenomena of these sand dunes is vital in enhancing the efficiency of understanding and management of terrains such as land degradation. In the existing models, however, there is lack of studies on the long - term behaviors of the sand dunes and application to actual topography. Therefore, this study applied the wind-vegetation model considering vegetation to the actual topography and analyzed the applicability of the wind-vegetation model by analyzing the long-term behaviors and comparing them with actual data. Through analysis, study found out that use of wind-vegetation model and data from unmanned aerial vehicle is effective in analyzing the changes of actual dune topography. Except for the boundary, the error of about 1m was generated compared with the change of the actual dune topography.

• Journal of Environmental Science International
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• v.18 no.1
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• pp.99-111
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• 2009

In this study vegetation structure was monitored focusing on slanting surface of stream for the purpose of developing a management plan and ecological restoration of small stream in Paju. The study was conducted by types of geographical structure, yearly flora, naturalization rate changes, actual vegetation changes, plant community changes. Slope area of small stream in Paju was varied in the slope range of $10{\sim}35^{\circ}$. The survey results of yearly flora showed that 37 species appeared in 2000, 55 species in 2001, 95 species in 2002, and 125 species in 2003. Therefore, the trend of continuous increase of flora each year was observed. In the case of yearly changes of actual vegetation, indigenous wetland herb community including Phragmites communis$(19.99%{\rightarrow}18.42%{\rightarrow}19.60%)$ did not show substantial changes in the area, while the influence of controlled flora such as Humulus scandens$(8.86%{\rightarrow}5.26%{\rightarrow}9.73%)$, and Ambrosia artemisiifolia$(1.06%{\rightarrow}1.43%{\rightarrow}6.93%)$ were increased. The vegetation structure investigated by 18 preset belt-transects also indicated that Phragmites communis and Miscanthus sacchariflorus were maintaining the status or decreasing the population, while the population of Humulus scandens, Ambrosia artemisiifolia, Setaria viridis, and Erigeron canadensis were greatly increased. Our proposal management to restore ecology is as follows: first, preservation and restoration of Phragmites communis landscape; second, restoration of potential stream vegetation community; third, selection and removal of controlled plants.

• Journal of the Korean earth science society
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• v.35 no.1
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• pp.54-68
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• 2014

In order to analyze the land surface properties in Seoul and its surrounding metropolitan area, several indices and land surface temperature were calculated by the Landsat satellites (e.g., Landsat 5, Landsat 7, and Landsat 8). The Landsat data came from only in the fall season with Landsat 5 on October 21, 1985, Landsat 7 on September 29, 2003, and Landsat 8 on September 16, 2013. The land surface properties used are the indices that represented Soil Adjusted Vegetation Index (SAVI), Modified Normalized Difference Wetness Index (MNDWI), Normalized Difference Wetness Index (NDWI), Tasseled cap Brightness, Tasseled cap Greenness, Tasseled cap Wetness Index, Normalized Difference Vegetation Index (NDVI) and Normalized Difference Built-up Index (NDBI) and the land surface temperature of the area in and around Seoul. Most indices distinguish very well between urban, rural, mountain, building, river and road. In particular, most of the urbanization is represented in the new city (e.g., Ilsan) around Seoul. According to NDVI, NDBI and land surface temperature, urban expansion is displayed in the surrounding area of Seoul. The land surface temperature and surface elevation have a strong relationship with the distribution and structure of the vegetation/built-up indices such as NDVI and NDBI. While the NDVI is positively correlated with the land surface temperature and is also negatively correlated with the surface elevation, the NDBI have just the opposite correlations, respectively. The NDVI and NDBI index is closely associated with the characteristics of the metropolitan area. Landsat 8 and Landsat 5 have very strong correlations (more than -0.6) but Landsat 7 has a weak one (lower than -0.5).

• Journal of Environmental Science International
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• v.18 no.4
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• pp.375-388
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• 2009

Numerical simulation is essential to indicate the flow of the atmosphere in the region with a complicated topography which consists of many mountains in the inland while it is neighboring the seashore. Such complicated topography produces land and sea breeze as the mesoscale phenomenon of meteorology which results from the effect of the sea and inland. In the mesoscale simulation examines, the change of the temperature in relation to the one of the sea surface for the boundary condition and, in the inland, the interaction between the atmosphere and land surface reflecting the characteristic of the land surface. This research developed and simulated PNULSM to reflect both the SST and vegetation effect as a bottom boundary for detailed meteorological numerical simulation in coastal urban area. The result from four experiments performed according to this protocol revealed the change of temperature field and wind field depending on each effect. Therefore, the lower level of establishment of bottom boundary suitable for the characteristic of the region is necessary to figure out the atmospheric flow more precisely, and if the characteristic of the surface is improved to more realistic conditions, it will facilitate the simulation of regional environment.

• Journal of The Geomorphological Association of Korea
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• v.26 no.3
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• pp.1-17
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• 2019

Naeseongcheon is Korea's representative sand stream, and it is one of the regions where the dynamic changes of various river topography developed in the sand bed can be observed. Most of drainage area near of the river channel are formed with Daebo granite, and the granite weathering zone is developed at the surface of hill. Due to the massive input of sediment flux, braided channel reaches are found some of the area. However, the results of the study shows that the alluvial layer is very thin in some reaches. In addition, bedrock or weathered materials, including the Tors are exposed at the channel beds. On the other hand, during the flood, a considerable amount of sediment was introduced, causing the massive sediment to be close to 1m thick. In addition, despite the short distance, large changes in the particle size and sorting of the sediment were observed. Vegetation, on the other hand, has been shown to have a significant effect on the development of the overall channel bed topography, as reported in previous studies. In small floods or low water levels, vegetation's protection role of the surface is predominates, but in large flood conditions, herbaceous loss at the surface of the point bars, accelerating the erosion of surface.

• Atmosphere
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• v.15 no.1
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• pp.1-16
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• 2005

Land-surface and soil processes significantly affect mesoscale local weather systems as well as global/regional climate. In this study, characteristics of land-surface models (LSMs) and soil models (SMs) that are frequently coupled into mesoscale meteorological models are investigated. In addition, detailed analyses on three LSMs, employed by the PSU/NCAR MM5, are provided. Some impacts of LSMs on heavy rainfall prediction are also discussed.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.111-124
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• 2010

To monitor the environment of land surface change is considered as an important research field since those parameters are related with land use, climate change, meteorological study, agriculture modulation, surface energy balance, and surface environment system. For the change detection, many different methods have been presented for distributing more detailed information with various tools from ground based measurement to satellite multi-spectral sensor. Recently, using high resolution satellite data is considered the most efficient way to monitor extensive land environmental system especially for higher spatial and temporal resolution. In this study, we use two different spatial resolution satellites; the one is SPOT/VEGETATION with 1 km spatial resolution to detect coarse resolution of the area change and determine objective threshold. The other is Landsat satellite having high resolution to figure out detailed land environmental change. According to their spatial resolution, they show different observation characteristics such as repeat cycle, and the global coverage. By correlating two kinds of satellites, we can detect land surface change from mid resolution to high resolution. The K-mean clustering algorithm is applied to detect changed area with two different temporal images. When using solar spectral band, there are complicate surface reflectance scattering characteristics which make surface change detection difficult. That effect would be leading serious problems when interpreting surface characteristics. For example, in spite of constant their own surface reflectance value, it could be changed according to solar, and sensor relative observation location. To reduce those affects, in this study, long-term Normalized Difference Vegetation Index (NDVI) with solar spectral channels performed for atmospheric and bi-directional correction from SPOT/VEGETATION data are utilized to offer objective threshold value for detecting land surface change, since that NDVI has less sensitivity for solar geometry than solar channel. The surface change detection based on long-term NDVI shows improved results than when only using Landsat.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.219-222
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• 2003

Bech scale tests were performed to evaluate the adaptability of industrial wastes, especially bottom ash, salg and phosphogypsum among others, for constructing the surface layer of a landfill or reclamation, which function is a vegetation base layer. In the test, columes test were used to check the extraction characteristics of wastes and small PVC soil-box that equipped the drainage device was used to model a performance of layers and to monitor the growth of plants at the composite layer of those. Tests have been continued during one and half year and It has been verified that bottom ash and phosphogypsum look like as a valuable material to safely reuse as the vegetation base layer even though some unconfined factors are remain.

• The Korean Journal of Ecology
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• v.21 no.4
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• pp.351-355
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• 1998

This study was carried out to investigate occurrence and distribution of cellular slime molds by vegetation in Mt. Seorak. Eleven species were isolated from surface soil samples as follows: P. violaceum, P. candidum, P. purpureum, D. brefeldianum, D. minutum, D. delicatm, D. crassicaule, D. macrocephalum, D. firmibasis, D. polycephalum and D. implicatum. The dorminant species was D. brefeldinum. D. delicatum, D. implicatum, D. polycephalum and P. candidum of them were isolated rarely in Korea. It can be thought that these results were caused by characteristics of forest zone and geographical condition which Mt. Seorak is located at east side of central areas of Korea.