• Journal of the Korean Geographical Society
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• v.43 no.3
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• pp.263-275
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• 2008

This Study deals with the comparative analysis on the estimation of surface soil erosion volume between South and North Korea using RUSLE model in Imjin River basin located on DMZ of Central Korea. Comparatively North Korea areas have been more eroded three times as much as South Korea parts. Because of cropland development such as com Held in the hillslope, in North Korea, more surface soil erosion and transportation to the river bed has given rise to frequent flood hazards. It seems that the study can dedicate to mitigation of environmental problems such as soil erosion and flooding in unaccessible Imjin River basin located on DMZ.

• Journal of the Korean association of regional geographers
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• v.14 no.1
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• pp.19-26
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• 2008

A validation study has been performed using the Soil and Water Assessment Tool(SWAT) model with data collected for the Neponset River watershed, which includes roughly 130 square miles of land located southwest of Boston. All of this land drains into the Neponset River, and ultimately into Boston Harbor. This paper presents the methodology of a SWAT model. The calculated contribution of the baseflow to the streamflow is far too high whereas the interflow is strongly underestimated. Alternatively, the modified and calibrated model yields far better results for the catchment. The modification allows hydrological processes to be modeled while not restraining the applicability of the model to catchments with other characteristics. For this study, the SWAT 2005 model is used with ArcGIS 9.1 as an interlace, and sensitivity analysis is performed to provide rough estimated values before adjusting sensitive input parameters during calibration period.

• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.544-561
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• 2004

Weekly monitoring of discharge and water quality in forested and agricultural subcatchments were performed to understand the difference of water quality caused by land uses in Doegwollyong area. Correlations between water quality variables including discharge were analyzed for the same purpose. There was little variation of water Quality in forested subcatchment. On the other hand, the range of water quality variation in agricultural subcatchment was wide due to soil loss and the application of chemical fertilizers and livestock manure. Dissolved oxygen(DO) had strong negative correlation with discharge in both subcatchments. Total nitrogen(T-N) and potassium ion(K$^{+}$) had stronger positive correlation with discharge in forested subacatchment than in agricultural one. On the other hand, total suspended sediments(TSS), total phosphorus(T-P), and chemical oxygen demand(COD) had stronger correlation with discharge in agricultural subcatchment than in forested one. As water pollution of the Doam Lake, especially the increase of T-P is serious, soil conservation is very important to improve water quality. In particular, the loss of soil and nutrients from late June till early July were more serious than any other seasons, therefore it is necessary to apply environmentally sustainable methods of cultivation.n.

• Journal of the Korean Geographical Society
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• v.45 no.5
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• pp.553-572
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• 2010

Grain size analysis of sediments and soils has been regarded as a one of the most important analytical methods in Earth Sciences. The results of grain size analysis by 10 different pretreatment procedures in loess-paleosol sediments are compared in the study. In spite of the most powerful effectiveness of dispersant(sodium hexametaphosphate) on the dispersions of sediments, the effects show large differences by its treatment orders with HCl. It may result from that $Na^+$ ions in the dispersant may not be able to effectively substitute $Ca^{2+}$ ions in the sediments due to the electrostatic forces between $Na^+$ and $Cl^-$ ions in the dispersant and HCl, respectively. Although $H_2O_2$ and HCl are more effective in dispersion than hot water, they do not affect greatly the dispersions. Therefore, the reliable results of grain size analysis can be obtained by selecting the adequate pretreatment procedures most suitable for the purposes of researches and characteristics of sediments.

• Journal of the Korean Geographical Society
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• v.44 no.1
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• pp.17-30
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• 2009

Paleostudies using lake sediment are essential to reconstruct environmental history of cental Mexico, where few documents on ancient civilizations and the colonial period exist. This study aims to reveal changes in the soil erosion rates through the calculation of sediment influx into the lake. The calculation is based on different kinds of chronologies and LOI. Sediment influx and dates for important events could be obtained in great detail through various chronological methods. Results show that corn agriculture was the most important reason to degrade the environmental status of the lake basin and European cattle raising was not much influential within the lake basin at least. It was possible to reveal a lot of recent environmental changes in detail, because the lake sediment used for this study has a very high sedimentation rate. Also, due to an accurate chronological framework, fundamental problems with the sediment were solved and reliable results could be produced.

• Journal of the Korean Geographical Society
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• v.44 no.3
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• pp.207-223
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• 2009

The TOPMODEL Topographic Index (TI) is widely used to predict the spatial distribution of soil moisture contents, The TI is one of terrain indices which are frequently used in spatially distributed environmental modelings. There have been studies on the evaluation and improvement of the TI. Most of them. however, have focused on only the modified multiple flow direction algorithm and algorithms for slope calculation have been paid little attention, In this research, we attempted to improve the TI by utilizing the infinitive flow direction (Dinf) algorithm and Horn slope algorithm. Then we attempt to analyze and evaluate the influence of the improved TI on hydrological responses of the TOPMODEL As a result. our approaching using the infinitive flow direction (Dinf) and Horn slope algorithm made the TI better than the multiple flow direction (MD8) - the multiple descent slope (MDS) algorithm. However, the model efficiency of discharges at the outlet was not increased. Our research may provide an insight to choose appropriate algorithms for calculating flow direction and slope in spatially distributed environmental modelings.

• Journal of the Korean Geographical Society
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• v.14
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• pp.1-8
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• 1976

본 고에서는 낙동강 하류지방의 배후습지성 호조에 대해서 살펴보았다. 후빙기 해면상승과 관련시켜 고찰할 때, 이들 호조는 삼림남발로 인한 가속된 토양침식 및 주요 하도의 하상 상승때문에 근래에 발달된 것이 아니라, 낙동강 범람원이 현해면을 기준으로 형성되어 가는 중에 발달된 지형임이 확실하다. 대실아언은 정양지와 박실지가 30년 또는 40년 이래에 생긴 호조라고 지적했다. 그러나, 대정6년(1917) 측도 1:50,000 지형도에 이 두 호조가 나타나 있는 것을 보면, 그가 채택한 주민의 증언은 사실과 다름이 분명하다. 주민의 증언은 이들 호조의 하단부에 공수시 황강의 역수를 막기 위해 쌓은 제방의 축조 년대를 가리키는 것이 아닌가 생각된다. 그리고 박실지는 흡지의 간척으로 과거에 비해 많이 축소되었다. 배후습지 및 배후습지성 호조는 확대되는것이 아니다. 토사축적과 간척으로 계속 축소되고 있는 것이 일반적인 경향이다. 배후습지성 지형은 한강 및 금강 하류에서도 발견되지만, 낙동강 하류지방에 가장 널리 분포한다.

• Journal of the Korean Geographical Society
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• v.34 no.3
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• pp.295-318
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• 1999

본 연구는 단양군 소백산맥 북서사면을 사례지역으로 농업적 토지이용의 수직적 분화를 파악하는 것을 목적으로 한다. 이 연구를 통하여 산지가 많은 우리 나라에서 산지사면을 농업적 측면에서 효율적으로 이용하는 방안을 제시할 수 있다. 단양군 소백산맥 북서사면 지역의 수직적 토지이용의 구성에 의한 농업생산지대의 형성 메카니즘을 농업경영 형태와 수직적 농업 토지이용의 면에서 살펴 보면 다음과 같다. 농업 생산기반 요인으로는 자연환경요소인 기후와 토양 및 해발고도, 경지 소유관계로 자가 경지소유, 노동력은 가족 노동력, 농기계화와 모터리제이션, 그리고 농가와 경지와의 거리를 들 수 있다. 그리고 사회.경제적 요인으로는 상전의 토지이용 변화, 인접지역의 재배작물 영향, 인접지역으로부터 전입인구, 교통의 발달정도 등을 들 수 있다. 마지막으로는 농업정책의 요인으로는 특화단지 조성, 협업생산체제와 1군 1명품 사업 등을 들 수 있다.

• Journal of the Korean Geographical Society
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• v.48 no.3
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• pp.366-386
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• 2013

This paper analyzes the drought and restriction on water supply in Taebaek City during the winter season in 2008 using Actor-Network Theory. Actor-Network Theory emphasizes and brings into view the role and act of non-human actors as well as human actors in various environmental issues. The fact that only Taebaek experienced restriction on water supply for 88 days although the winter season drought in 2008 affected the whole nation, requires a synthetic analysis of both human and non-human actors and their relationships and networks embedded in Taebaek City at that time. This paper shows that both human and non-human actors including Taebaek City Hall, Korea Water Resource Corporation, Taebaek citizen, the water supply facilities, Gwangdongdam, obsolete water pipes, the topography of Taebaek, soil, the change of industry, and population interact one another transforming the geography of water in Taebaek. This study helps to understand the complex processes related to drought disasters at a specific local scale and to provide appropriate measures to drought.

• Journal of The Geomorphological Association of Korea
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• v.21 no.4
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• pp.133-147
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• 2014

Reducing the range of target landform, is required to save the time and cost before real field survey in the case of inaccessible landform such as talus. In this study, Weight of Evidence modeling, which is a Target-driven spatial analysis statistics methods, has been applied to reduce the field survey range of target landform. In order to apply the Weight of Evidence analysis, a likelihood ratio was calculated on the basis of the result of correlation analysis between geomorphic factors and GIS information after selection of geomorphic factors regarding talus. A best combination, which has the biggest possibility for Talus Potential Index, was found by using SRC and AUC methods after calculating the number of cases for each thematic maps. This combination which includes aspect, geology, slope, land-cover, soil depth and soil drainage factors, showed quite high accuracy by 74.47% indicating the ratio of real existent talus to potential talus distribution.