• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2001.06a
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• pp.151-152
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• 2001

A common problem of the model simulations of the land surface - atmosphere interaction is to choose the appropriate spatial scale and resolution at which the simulations are to be performed. The accuracy of energy and water exchange predictions between the land surface and the atmosphere in regional and global scale atmospheric models is mainly influenced by: model simplifications applied to describe the spatial heterogeneity of land surface properties within individual grid cells; ignoring the variability of sub-grid properties (e.g. relief, vegetation, soils), and; lacks of necessary input meteorological and biophysical data.(omitted)

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2019.08a
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• pp.150-150
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• 2019

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.4
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• pp.193-203
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• 2006

This study conducts mapping of the results of topographical dissected degree analysis using GIS and analyzes relation between dissected degree and land use of study area. Application of GIS typographical dissected degree analysis can greatly save time and efforts comparing with traditional manual work, and makes it possible to vary analysis variables widely, which gives possibility to carry out 2-dimensional research using these results. This study, taking start from such background, tries to find the way to carry out dissected degree analysis with the use of GIS, compares the results of the analysis with the land use map, and tries to find the ways of practical application of this analysis results. The results of analysis of the relation between basin dissected degree and agricultural land use of Gangneungnamdae river study area show that for agricultural land use topographical dissection is mostly distributed in quite developed area. Specifically, land used for paddy and dry fields appeared to have higher level of correlation with dissection degree. When comparing dissected degree and agricultural land use interrelation for each area, comparison of intensively formed urban districts with suburbs showed low correlation.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.194-198
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• 2008

Significant soil erosion and water quality degradation issues are occurring at highland agricultural areas of Kangwon province because of agronomic and topographical specialities of the region. Thus spatial and temporal modeling techniques are often utilized to analyze soil erosion and sediment behaviors at watershed scale. The Soil and Water Assessment Tool (SWAT) model is one of the watershed scale models that have been widely used for these ends in Korea. In most cases, the SWAT users tend to use the readily available input dataset, such as the Ministry of Environment (MOE) land cover data ignoring temporal and spatial changes in land cover. Spatial and temporal resolutions of the MOE land cover data are not good enough to reflect field condition for accurate assesment of soil erosion and sediment behaviors. Especially accelerated soil erosion is occurring from agricultural fields, which is sometimes not possible to identify with low-resolution MOD land cover data. Thus new land cover data is prepared with cadastral map and high spatial resolution images of the Doam-dam watershed. The SWAT model was calibrated and validated with this land cover data. The EI values were 0.79 and 0.85 for streamflow calibration and validation, respectively. The EI were 0.79 and 0.86 for sediment calibration and validation, respectively. These EI values were greater than those with MOE land cover data. With newly prepared land cover dataset for the Doam-dam watershed, the SWAT model better predicts hydrologic and sediment behaviors. The number of HRUs with new land cover data increased by 70.2% compared with that with the MOE land cover, indicating better representation of small-sized agricultural field boundaries. The SWAT estimated annual average sediment yield with the MOE land cover data was 61.8 ton/ha/year for the Doam-dam watershed, while 36.2 ton/ha/year (70.7% difference) of annual sediment yield with new land cover data. Especially the most significant difference in estimated sediment yield was 548.0% for the subwatershed #2 (165.9 ton/ha/year with the MOE land cover data and 25.6 ton/ha/year with new land cover data developed in this study). The results obtained in this study implies that the use of MOE land cover data in SWAT sediment simulation for the Doam-dam watershed could results in 70.7% differences in overall sediment estimation and incorrect identification of sediment hot spot areas (such as subwatershed #2) for effective sediment management. Therefore it is recommended that one needs to carefully validate land cover for the study watershed for accurate hydrologic and sediment simulation with the SWAT model.

• Journal of Ecology and Environment
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• v.33 no.3
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• pp.229-236
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• 2010

We conducted field surveys of amphibians and reptiles over a two-year period in 16 lagoons along the eastern coastline of South Korea, and determined the habitat characteristics correlated with the number of amphibian and reptilian species and individuals. We documented 11 amphibian species and 8 reptilian species. The dominant amphibian species was the black-spotted pond frog (Rana nigromaculata), and the dominant reptilian species was the red-eared turtle (Trachemys scripta elegans), an invasive species. Among the 14 habitat characteristics, connectivity to mountainous area significantly affected the number of amphibian and reptilian individuals. Other factors, including emerged plant cover, salinity, pH, the number of birds for amphibians and connectivity to agricultural land, lagoon perimeter length for reptiles also influenced the number of species or individuals of them. Our results demonstrate that these lagoons are home to more amphibians and reptiles than has been previously known. To effectively conserve herpetofauna in the lagoon ecosystem, lagoons as well as surrounding wetlands, grasslands, and mountainous areas should be protected.

• The Korean Journal of Pesticide Science
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• v.12 no.1
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• pp.24-33
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• 2008

In this study, the mobility of seven pesticides from soil in different slopes was investigated by simulated rainfall under field conditions. Simulated rainfall subjected to $22\;mm\;hr^{-1}$ was treated using rainfall simulator after 12 hr of pesticide treatment. Amounts of the pesticides were measured in run-off water samples. The soil samples collected before and after rainfall from upper, middle and lower parts and three different depths of sloped-plot were also analyzed. At result, the order of the amount of pesticide residues was $0{\sim}15$ > $15{\sim}30$ > $30{\sim}45\;cm$ of soil depth and no pattern was shown in upper, middle and lower, and different slopes in soil samples. all pesticides from the run-off water samples collected from soils were detected maximum 96% within 60 minutes after first collection except carbendazim and cypermethrin which have the lowest water solubilities. These results revealed that mobility of pesticides can be dependant mainly on soil textures and physicochemical properties of pesticides. Therefore, it can be suggested that selection of pesticides should be considered for properties of pesticide in the alpine and sloped-land.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.414-417
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• 2008

We have extracted a surface deformation map of a part of Canisteo Peninsula on Amundsen Sea in West Antarctica by applying 4-pass DInSAR technique to two ERS-1/2 tandem pairs obtained on October 21-22, 1995 (diff-pair) and March 9-10, 1996 (topo-pair), and analyzed changes of glaciers, sea ice, ice shelves, and their kinematic interactions. We observed fast motion of glaciers pushing the adjoining sea ice. Some interferometric phases indicate the up-rise of sea ice of which type is thought to be land-fast ice to exert repulsive force against the pushing glacier. There were other glaciers and sea ice that moved to the same direction, suggesting that the sea ice in these regions was land-fast ice weakly harnessed to sea bottom or pack ice not harnessed at all. Several small circular fringes in ice shelves suggested that islands or seamounts on the bottom of ice shelves deterred the movement of ice shelves, resulting in the rise of ice surface.

• Journal of Korean Society of Rural Planning
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• v.9 no.1 s.18
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• pp.19-26
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• 2003

This study investigated and analyzed the current status and operations of tourism farms in the Chuncheon area. By adopting the GIS, an analysis was made of whether the five old tourism farms utilized suitability and how they could open a new one in a suitability. The following results were drawn from the analysis of natural and social suitability factors and accessibility. Time requirements were analyzed taking into account that a majority of tourists came from Seoul and Gyeonggi, area. Four of the five tourism farms were within one hour travel, from these areas but it seemed impossible that they could be reached within one hour considering the actual road conditions and traffic. The natural and social suitability factors of a tourism farm were overlay-analyzed. The land of the first and second class that was considered to be suitable for a tourism farm was $17.12km^2$, which accounted for 1.38% of the entire area examined in the study and 11.50% of the entire agricultural land. The area that was evaluated to be suitable for a tourism farm will be able to attract new tourism farms in the future.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2011.11a
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• pp.7-10
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• 2011

The semi-arid and arid regions comprise almost 40 percent of the world's land surface. The low and erratic precipitation pattern is the single most significant contributor for limiting crop production in such regions where rainfall is the source for surface, soil and ground water. In a changing climate, the semi-arid and arid regions would increasingly face the challenge of water scarcity. According to the relevant literature; under the assumption of a doubling of the current atmospheric CO2 concentration, irrigation demand was estimated to increase for wheat and to decrease for second crop maize in a Mediterranean environment of Turkey in the 2070s. Crop evapotranspiration would decrease due to stomata closure. Reference evapotranspiration and potential soil evaporation were projected to increase by 8.0 and 7.3%, respectively, whereas actual soil evaporation was predicted to decrease by 16.5%. Drainage losses below 90 cm soil depth were found to decrease mainly due to lesser rainfall amount in the future.

• Journal of Korean Society of Rural Planning
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• v.30 no.3
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• pp.55-62
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• 2024

This study aimed to resolve issues in performance monitoring of the ecological sector of the Agricultural Environment Conservation Program through a comparative study of domestic ecological monitoring cases and to identify suitable performance monitoring methods for the project. To achieve this objective, current performance monitoring of the Agricultural Environment Conservation Program was compared and analyzed with domestic ecological monitoring cases to examine their applicability. Research results indicate that domestic ecological monitoring covers a wide range, making it difficult to diagnose the ecological environment at the village level. Therefore, it seems challenging to use these data for evaluating the performance of residents' activities. To accurately assess performances of participating villages in the project, on-site monitoring of the target areas is essential. For this purpose, efforts should be focused on strengthening on-site monitoring through the establishment of collaborative systems. However, domestic ecological monitoring can be utilized for long-term performance monitoring in the Agricultural Environment Conservation Program. By extracting necessary data on agricultural areas through geographic information and particularly by utilizing survey results according to the 'cultivated land ecosystem' type, long-term performance of the project could be evaluated. Accordingly, this study can serve as foundational research for establishing an ecological performance monitoring plan and system suited to the project.