• Journal of the Korean Geographical Society
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• v.44 no.4
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• pp.557-576
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• 2009

Physical based water balance model had better simulation results than conceptial model, however it is difficult to obtain input data for the model. This study suggests some methods to obtain parameter values of BROOK90 from meteorological data, soil map, land-use map. Comparing measured and simulated discharge proved the methods to be valid. For validation model($2001{\sim}2003$), comparing measured and simulated discharge a daily mean bias error, Nash-Sutcliffe's model efficiency coefficient, coefficient of determination equal to -0.517, 0.87 and 0.89 respectively. The results of this study would be helpful to the hydrological study using physical based hydrological model not only in super site but in other catchments.

• Journal of the Economic Geographical Society of Korea
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• v.15 no.2
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• pp.192-205
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• 2012

This study estimates how much climate variables affect the land price and acreage of rice paddy and dry farm field in agriculture with the case of Gangwon-do in Korea. To this end, we capitalize upon the Ricardian approach based upon the panel data on climate, soil and geography, farmland prices and acreage, other economic and social variables for 11 municipal units comprising Gangwon-do during the period of 1992-2010. Our empirical analysis shows that the temperature variable has negative economic impacts on the price and acreage of rice paddy and dry farm field, confirming that the temperature variable is much significant than that of precipitation in global warming. On the other hand, the other determinants of farmland price and acreage are different with the type of farmland in Gangwon-do.

• Journal of the Korean association of regional geographers
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• v.10 no.3
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• pp.568-578
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• 2004

This study is aimed at investigating floodgate characteristics and environmental issues in Gwangjucheon and examining possible problems of expanding river maintenance water being carried on in the context of river recovery works. In general, the obtained results show the following. The treatment water provisioned in the restoration project of the drying stream going through the water circulation device can pollute the land and groundwater in the Gwangjucheon Basin. Besides, although about $17,565m^3$/day of water is available in the upper ground, most of it go to the junction and exhausting directly to the waste water treatment or going into the groundwater. Because of the drying stream, the amount of water going to the ground is increased. Therefore, efficient land use along with regulations to protect cultivated land and ensure recovery works of city stream through the recovery of water circulation by constructing and expanding a special drainage system are of vital importance.

• Journal of the Korean association of regional geographers
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• v.17 no.5
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• pp.521-535
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• 2011

This study intended to explain the relationship between climate change and magnetic susceptibility of estuarine sediment. Data of OSL dating and magnetic susceptibility from estuarine tidal sediment were compared with various climate change data. During the last Holocene, the intense of magnetic susceptibility related with weaker Siberian High and stronger Asian Summer Monsoon. It is explained that high precipitation and runoff made much fluvial sediment input to the estuary. From the early to mid Holocene, there is no clear relationship between climate change and MS because of the much coastal sediment input caused by rapid sea level rise and the formation of upland soil and coastal marsh. These results contribute to reconstruct paleo-environmental changes of west coast of Korea, in the way of using benefit of ubiquitous estuarine tidal flats and relatively useful magnetic susceptibility methodoloy.

• Journal of the Korean association of regional geographers
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• v.13 no.2
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• pp.129-142
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• 2007

The Purpose of this study is to evaluate the value of abandoned paddy fields as wetland ecosystems and their suitability as habitats for various species. Physical and chemical characteristics of soils and the change of vegetation in paddy fields were analysed -with the passage of time after cease of cultivation. The results of analyses for soil characteristics, vegetation succession, and functional values of abandoned paddy fields as wetlands were as follows: First, top soils become coarser as years after abandonment increase. Second, as the years of abandonment passed. there were significant differences in organic matter, available phosphorate and calcium, while not in magnesium and cation exchange capacity(CEC). Third, species increased from early stage till middle stage, and decreased in late stage. In similarity analysis of species composition, sites were classified into three groups according to the stage of succession. Upper and lower terraces at Daetgol were classified as early stage of succession. The 1st, 2nd and 3rd terraces at Nonbanggol were in middle stage, while tile 4th and 5th were in late stage. Forth, according to evaluation sheets of MoE and RAM(Rapid Assessment Method) standards, me overall average of functional value of Nonbanggol site were 2.13, classified as "common".

• Journal of The Geomorphological Association of Korea
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• v.15 no.2
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• pp.37-53
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• 2008

This study has developed a water balance model for the catchment of Byungchun river using a BROOK90 4.4e physical deterministic water balance model with the long-term meterological data and stream run off data obtained from the basin of Byungchun river in Korea. It is intended that the validation model with calibrated model fitting parameter can build a long-term water balance plan for a period when meterological data are available but stream runoff data are not. Results of this study have satisfied the first expectation as an experiment for water balance modeling since measured stream runoff data have turned out to be very similar to simulated stream runoff data. Through the confirmation of model fitting parameters and validated simulation, water balance for the period of 1998 to 2006 has been restored. Unless the conditions of geomophology, vegetation, soil and land use change, meterological data alone can produce various hydrometeorological data related to stream runoff amount, soil water amount, and evapotranspiration. This study opens up a new horizon in restoring water balance in the past as well planning water balance in the present. The obtained results from this study are expected to be used in predicting future water balance in the wake of the changes in climate and vegetation in Korea.

• Journal of The Geomorphological Association of Korea
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• v.20 no.1
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• pp.21-33
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• 2013

Weight of evidence model was applied for potential mapping of mountainous wetland to reduce the range of the field survey and to increase the efficiency of operations because the surveys of mountainous wetland need a lot of time and money owing to inaccessibility and extensiveness. The relationship between mountainous wetland location and related factors is expressed as a probability by Weight of evidence model. For this, the spatial database consist of slope map, curvature map, vegetation index map, wetness index map, soil drainage rating map was constructed in Yeongnam area, Korea, and weights of evidence based on the relationship between mountainous wetland location and each factor rating were calculated. As a result of correlation analysis between mountainous wetland location and each factors rating using likelihood ratio values, the probability of mountainous wetlands were increased at condition of lower slope, lower curvature, lower vegetation index value, lower wetness value, moderate soil drainage rating. Mountainous Wetland Potential Index(MWPI) was calculated by summation of the likelihood ratio and mountainous wetland potential map was constucted from GIS integration. The mountain wetland potential map was verified by comparison with the known mountainous wetland locations. The result showed the 75.48% in prediction accuracy.

• Journal of the Korean Geographical Society
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• v.31 no.2
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• pp.106-127
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• 1996

In Korea, modern geomorphology has developed as one of main subjects in geography, such as in Europe. Geomorphology is one of the most advanced specialties in the geography dicipline, since foundation of Korean Geographical Society in 1945. Untill 1960's study, first generation of the Korean geomorphologists trained the younger ones, together with energetic research activities. Their great works in education and research established the base of ulterier development of the geomorphology in Korea. Since 1970s, research manpower and quality has incresed rapidly, partly due to the various international activities and cooperations of Korean geomorphologists. Owing to above development, Korean geomorphologist was able to found "The Geomorphological Association of Korea" in 1990 and publish "Journal of GAK", since 1994. Furthermore, geomorphologists are playing important roles in interdisciplinary academic societies, such as "The Korean Quaternary Assocition". Still 1960s, our research had focused on the identification and interpretation of erosional surfaces in Korea Peninsular. Of course, W.M. Davis's "Geographical Cycle Theory" and L.C. King's "Pedimentation Theory" had a great influence on the Koerans' works. After 1970s, the study of erosional surface played the important role in setting up the morphoclimatic viewpoint and methodology. Research scope tend to be notably broad and various than it was untill 1960's. Disposotion of the scientific methods and techniques become more and more apparent. These trends of research has settled precise descreption and interpretation of actual landforms, based on the careful field works, scientific measuring, and analisis, rather than methodology focused on the particular master theories. Recent geomorphological researches show the scope from climatic geomorphology and Quaternary geomorphology to granite and limestone weathering, pedo-geomorphogenic environment and periglacial landforms, focused on the small-to-medium scales. And then there have been new trying to interprete erosional surfaces such as hillslopes and terraces. Also, studies of coastal and plain landforms have been successfully developed. Recent new trends show the quantitative and analytic modelling using field measurement and laboratory work, and study on the human impacts on the natural landforms.y on the human impacts on the natural landforms.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.1
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• pp.133-149
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• 2022

Existing domestic studies on estimating rice yield were mainly implemented at the level of cities and counties in the entire nation using MODIS satellite images with low spatial resolution. Unlike previous studies, this study tried to estimate rice yield at the level of eup-myon-dong in Gimje-si, Jeollabuk-do using Sentinel-2 satellite images with medium spatial resolution, rainfall and soil data, and then to evaluate its accuracy. Five vegetation indices such as NDVI, LAI, EVI2, MCARI1 and MCARI2 derived from Sentinel-2 images of August 1, 2018 for Gimje-si, Jeollabuk-do, rainfall and paddy soil-type data were aggregated by the level of eup-myon-dong and then rice yield was estimated with gamma generalized linear model, an expanded variant of multi-variate regression analysis to solve the non-normality problem of dependent variable. In the rice yield model finally developed, EVI2, rainfall days in September, and saline soils ratio were used as significant independent variables. The coefficient of determination representing the model fit was 0.68 and the RMSE for showing the model accuracy was 62.29kg/10a. This model estimated the total rice production in Gimje-si in 2018 to be 96,914.6M/T, which was very close to 94,470.3M/T the actual amount specified in the Statistical Yearbook with an error of 0.46%. Also, the rice production per unit area of Gimje-si was amounted to 552kg/10a, which was almost consistent with 550kg/10a of the statistical data. This result is similar to that of the previous studies and it demonstrated that the rice yield can be estimated using Sentinel-2 satellite images at the level of cities and counties or smaller districts in Korea.

• Journal of the Korean Geographical Society
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• v.47 no.1
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• pp.60-78
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• 2012

The main objective of this study is to conduct subnational population projections of Korea based on a Myriad Things" (萬物門), which is part of Seongho's representative work entitled $Miscellaneous$ $Explanations$ $of$ $Seongho$ (星湖僿說), has been in this paper in order to understand Seongho's "thinking on geography". To do so, contents related to geography were selected and these were discussed and interpreted in terms of the classification system of today's geographical knowledge. Following is the result of this research. First, information on astronomical geography and natural geography such as uplift, tornado, structure of soil, and the $yut$ board as well as humangeographical topics such as wild $ginseng$, cigarettes, hot pepper, traditional fruits and nuts (chestnuts, jujubes, and persimmons), Goryeo paper (Korean paper), mulberry trees, cotton plants, natural dye, policy about horses, magnetic compass needles, and farming implements for rice transplantation are mentioned in "Myriad Things" in relation to geography. Second, the depth of information described varies from topic to topic, but the topics on tornado and magnetic compass needles, horses, wild ginseng, traditional fruits and nuts, and $yut$ board are described in depth and in detail. Third, authenticity of the contents on these topics are "true" insofar as bibliographical information and citations are provided for support. Fourth, these topics reflect the interests and circumstances that are related to the "economic improvement of common people's livelihood" in those days, such as agriculture, crops, and transportation of goods. Fifth, the bibliography and citations explaining all instances reveal that China (Qing) is a great civilization of the advanced world and that the scholarship of Joseon relied on and accepted it. Sixth, except for horse raising and management, farming implements for rice transplantation, sericulture, and natural dying of cloth, most of the topics are useful even today. In short, theres is a profound aspect to the content that makes it possible to estimate the "geographical thinking". In general, the focus of the content of this book directly linked to the practical agricultural economy of the common people.