• Journal of Wetlands Research
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• v.17 no.1
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• pp.26-37
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• 2015

Halophyte distribution pattern and area in the Suncheon-bay and Beolgyo estuary coastal wetlands were analyzed using KOMPSAT-2 landsat images were taken in 2008 and 2009, and field investigations were fulfilled for confirming the precise boundaries of individual halophyte areas. The salt-marsh vegetation in those areas can be classified mainly into two dominant communities: Suaeda japonica-dominant and Phragmites communis-dominant communities. In order to identify sedimentary characteristics, tidal-flat surface leveling and sedimentary facies analysis had been conducted. The sedimentary facies of marsh area are mostly silty clayey and clay facies with a little seasonal change and its slope is very gentle (0.0007~0.002 in gradient). Phragmites communis and Suaeda japonica communities were distributed in the mud-flat zone between 0.7 m and 1.8 m higher than MSL (mean sea level): zone of 1.1~1.8 m in the former and zone of 0.7~1.3 m in the latter. In the Suncheon-bay estuarine wetland, on the basis of 2009 distribution, Phragmites communis-dominant and Suaeda japonica-dominant communities are about $0.79km^2$ and $0.22km^2$ in distribution area, respectively. On the other hand, Bulgyo estuarine marsh shows that the distribution areas of Phragmites communis-dominant and Suaeda japonica-dominant communities are about $0.31km^2$ and 0.031km2 in distribution area, respectively. Individual 105 and 60 dominant community areas and their distribution patterns can be well defined and indicated in the Suncheon-bay and Bulgyo estuarine marshes, respectively. The distribution pattern and area of hylophyte communities analyzed in this study based on 2008/2009 satellite images would be valuable as a base of future monitoring of salt-marsh related studies in the study area which is the most important salt-marsh research site in Korea.

• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.213-220
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• 2015

This study was carried out to determine the distribution of factors as effected by debris flow in Ulsan and Pusan metropolitan areas because mainly debris flow caused by typhoons and local heavy rainfall events is mainly attributed to damage of human being ad property. The high risk degree of debris flow was to affected by east (20%), northeast (20%) and northwest (20%) slopes with stand age class with elevation (69%) of 100-200 (33%). Also, the risk was high in high erosion collapse degree with slope degree of $20-25^{\circ}$ with over 300 mm (100%) of maximum daily rainfall events and 50-100 mm (50%) or >100 mm (50%) of maximum hourly rainfall events with <5 km of stream path and <50 ha of catchment area. Landslide debris and wood residue flow was also related to igneous rocks (73%) and bank collapse types of debrs flow (57%).

• Journal of the Korean association of regional geographers
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• v.19 no.4
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• pp.600-614
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• 2013

This study aims to examine spatially-detailed changes and projection of subtropical climate zones based on the modified K$\ddot{o}$ppen-Trewartha's climate classification and extreme temperature indices using $1km{\times}1km$ high resolution RCP 4.5 and RCP 8.5 climate change scenarios based on PRIDE model over the Republic of Korea. Subtropical climate zones currently located along the southern coastal region. Future subtropical climate zones would be pushed northwards expanding to the western and the eastern coastal regions as well as some metropolitan areas. For both scenarios, the frequency of cold-related extreme temperatures projects to be reduced while the frequency of hot-related ones projects to be increased. Especially, hot days with $33^{\circ}C$ or higher temperature projects to occur more than 30 days over the most of regions except for some mountain areas with high altitudes during the period of 2070~2100. This study might provide essential information to make climate change adaptation processes be enhanced.

• Atmosphere
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• v.26 no.1
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• pp.141-158
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• 2016

The objective of this study is to examine the impact of urban canopy and the horizontal resolution on simulated meteorological variables such as 10-m wind speed, 2-m temperature and precipitation using WRF model for a local, convective rainfall case. We performed four sensitivity tests by varying the use of urban canopy model (UCM) and the horizontal resolution, then compared the model results with observations of AWS network. The focus of our study is over the Seoul metropolitan area for a convective rainfall that occurred on 16 August 16 2015. The analysis shows that mean diurnal variation of temperature is better simulated by the model runs with UCM before the convective rainfall. However, after rainfall, model shows significant difference in air temperature among sensitivity tests depending on the simulated rainfall amount. The rainfall amount is significantly underestimated in 0.5 km resolution model run compared to 1.5 km resolution, particularly over the urban areas. This is due to earlier occurrence of light rainfall in 0.5 km resolution model. Earlier light rainfall in the afternoon eliminates convective instability significantly, which prevents occurrence of rainfall later in the evening. The use of UCM results in a higher maximum rainfall in the domain, which is due to higher temperature in model runs with urban canopy. Earlier occurrence of rainfall in 0.5 km resolution model is related to rapid growth of PBL. Enhanced mixing and higher temperature result in rapid growth of PBL, which provides more favorable conditions for convection in the 0.5 km resolution run with urban canopy. All sensitivity tests show dry bias, which also contributes to the occurrence of light precipitation throughout the simulation period.

• Korean Journal of Environment and Ecology
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• v.38 no.1
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• pp.48-54
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• 2024

This study conducted a survey from April 2021 to December 2022 to investigate habitat factors affecting bird diversity in the region between Cheonwangbong Peak and Aghwibong in Baekdudaegan protected area, South Korea. Since the region has a spatial scale of 736.4 km² and is an area where a wide variety of habitats are mixed, we selected 20 survey areas of 3 km x 3 km by analysis of habitat homogeneity. As a result of analyzing the relationship between habitat environment and bird diversity in the survey area, it was found that the diversity of bird communities was directly or indirectly related to the diversity of terrestrial insects, slope, average habitat area, mean size of patches, elevation, and forest type, and distance from agricultural land. The slope of habitat, forest type, and distance from agricultural land affect the occurrence of food sources directly and indirectly, and the average area of habitats and forest type is closely related to the structural diversity of habitats. Therefore, it is determined that the diversity of bird communities is affected by the amount of food generated within the habitat and the diversity of habitats. It is determined that the relationship between bird communities and habitat environments in this surveyed region can be basic ecological data for establishing forest management measures to promote the diversity of bird communities.

• Journal of Korean Academy of Rural Health Nursing
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• v.4 no.1
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• pp.22-30
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• 2009

Purpose: The purpose of this study was to explore the prevalence of Clornorchiasis and related factors, targeting inhabitants living in a 5 Km area of the Yeongsan River and to identify knowledge related to Clornorchiasis and intended behavioral changes related to risk of infection. Method: The data were collected from December 16, 2008 to January 10, 2009. A total of 553 questionnaires were distributed, 28 were deleted as answers were not complete, resulting in 525 copies being used for data analysis, which was done using frequency, percentage, $x^2$-test, and t-test with the SPSS 12.0 program. Results: Clornorchiasis was found in 25 persons of the 525 (4.8%). As for knowledge on Clornorchiasis, the Clornorchiasis group had a higher mean score of 10.08 $({\pm}4.96)$, of a possible 17, than the negative group score of 9.42 $({\pm}4.81)$, but, the difference was not statistically significant. The intended behavioral change related to risk of infection, according to presence of infection or not, was statistically significant. Conclusion: Effective management of Clornorchiasis demands management targeted at the inhabitants living in all of the risk areas without any distinction according to sex, areas, live food diet or not, nor liquor consumption or not.

• Korean Journal of Remote Sensing
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• v.36 no.5_1
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• pp.749-762
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• 2020

Precipitation is closely related to various hydrometeorological phenomena, such as runoff and evapotranspiration. In Korean Peninsula, observing rainfall intensity using weather radar and rain gauge network is dominating due to their accurate, intuitive and precise detecting power. However,since these methods are not suitable at ungauged regions, rainfall detection using satellite is required. Satellite-based rainfall data has coarse spatial resolution (10 km, 25 km), and has a limited range of usage due to its reliability of data. The aim of this study is to obtain finer scale precipitation. Especially, to make the applicability of satellite higher at ungauged regions, 10 km satellite-based rainfall data was downscaled to 1 km data using MODerate Resolution Imaging Spectroradiometer (MODIS) based cloud property. Downscaled precipitation was verified in urban region, which has complex topographical and environmental characteristics. Correlation coefficient was similar in summer (+0), decreased in spring (-0.08) and autumn (-0.01), and increased in winter (+0.04) season compared to Global Precipitation Measurement (GPM) based precipitation. Downscaling without calibration using in situ data could be useful in areas where rain gauge system is not sufficient or ground observations are rarely available.

• Journal of Ecology and Environment
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• v.46 no.4
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• pp.316-323
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• 2022

Background: We developed a habitat suitability index (HSI) model for Pedicularis hallaisanensis, a Grade II Endangered Species in South Korea. To determine the habitat variables, we conducted a literature review on P. hallaisanensis with a specific focus on the associated spatial factors, climate, topography, threats, and soil factors to derive five environmental factors that influence P. hallaisanensis habitats. The specific variables were defined based on the collected data and consultations with experts in the field, with the validity of each variable tested through field studies. Results: Mt. Seorak had a suitable habitat area of 2.48 km² for sites with a score of 1 (0.62% of total area) and 0.01 km² for sites with a score of 0.9. Mt. Bangtae had a suitable habitat area of 0.03 km² for sites with a score of 1 (0.02% of total area) and 0 km² for sites with a score of 0.9. Mt. Gaya showed 0.13 km² of suitable habitat for sites with a score of 1 (0.17% of total area) and 0 km² for sites with a score of 0.9. Lastly, Mt. Halla showed 3.12 km² of suitable habitat related to sites with a score of 1 (2.04% of total area) and 4.08 km² of sites with a score of 0.9 (2.66% of total area). Mt. Halla accounts for 73.1% of the total core habitat area. Considering the climatic, soil, and forest conditions together with standardized collection sites, our results indicate that Mt. Halla should be viewed as a core habitat of P. hallaisanensis. Conclusions: The findings in this study provide useful data for the identification of core habitat areas and potential alternative habitats to prevent the extinction of the endangered species, P. hallaisanensis. Furthermore, the developed HSI model allows for the prediction of suitable habitats based on the ecological niche of a given species to identify its unique distribution and causal factors.

• Journal of the korean Society of Automotive Engineers
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• v.8 no.3
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• pp.46-54
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• 1986

Driving pattern of gasoline passenger car was measured and analyzed at some areas(6urban area routes, 4 radial routes, 4 circular routes)in Seoul city. Measured items were vehicle speed, engine speed, intake manifold vacuum, and fuel consumption. Driving pattern data were reappearanced with engine dynamometer. Results of this investigation might be summarized as below; 1. When we compared urban area route with radial or circular route in rush hour, it was found that the average vehicle speed was measured to be lower about 25% and fuel consumption to be higher about 12% in urban area route. 2. Average vehicle speed was measured to be higher about 30% and driving resistance output to be higher about 25% in non-rush hour, but average fuel economy was increased a little. 3. On the bases of average fuel economy and characteristics of exhaust emissions, optimum driving vehicle speed was found about 60 km/h in the 4th(top)and about 40km/h in the 3rd in driving of experimental engine. 4. Idling frequency and exhaust emissions of CO,HC were related to idling closely. But exhaust emission of NOx, which had nothing to do with idling frequency, had relation to acceleration time ratio.

• Economic and Environmental Geology
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• v.41 no.5
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• pp.563-575
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• 2008

The ore depositional and geochemical exploration on Bougouni area in Mali, central-western Africa covering $2,000\;Km^2$ was conducted for determining the detailed survey area. According to the results of this exploration, the highly potential area for the zinc-tin-gold-silver mineralization was found in Kolani and Riarako areas. The contents of zinc in heavy sand collected in the stream sediments range from 14 to 8,600 ppm, while the mean values of zinc in this area are 543 ppm with threshold($x+2{\sigma}$) of zinc anomalies being 1,000 ppm in Bougouni area. Generally zinc anomalies are associated with the tin and molybdenum anomalies and hence the anomalous area was selected for the detailed survey area for tracing the primary zinc and precious ore deposits related to these anomalies in following project.