Assessment of soil erosion in Mongolia by climate change using RUSLE model
RUSLE 모델을 이용한 기후변화에 따른 몽골의 토양 유실 평가
- 주제(키워드) Assessment of soil erosion , RUSLE , GIS , Climate change , Mongolia , national scale , land management
- 발행기관 고려대학교 대학원
- 지도교수 전성우
- 발행년도 2020
- 학위수여년월 2020. 8
- 학위구분 석사
- 학과 대학원 환경생태공학과
- 세부전공 환경계획및조경학전공
- 원문페이지 56 p
- UCI I804:11009-000000232226
- DOI 10.23186/korea.000000232226.11009.0001170
- 본문언어 영어
- 제출원본 000046048351
초록/요약
Issues related to soil erosion and land resources are one of the highly significant environmental issues in Mongolia. Mongolia has high mountain ranges ranging from 2,500m to 3,500m above sea level, and these mountainous regions have the topographical characteristic that has a higher risk of landslides than flat land. Especially, a country with relatively high altitude and continental climate as Mongolia, soil erosion and degradation of land resources has been negatively affecting the ecosystem, crop production. In recent years, soil erosion is increasingly being recognized as a hazard. In order to establish an appropriate environmental management plan for soil erosion and soil degradation in Mongolia, it is necessary to evaluate the vulnerability of soil erosion and establish a land use management plan to protect the land resources accordingly. However, investigation for the assessment of soil erosion was performed only in some regions of Mongolia, and detailed studies on soil erosion and land degradation that represent the whole territory of Mongolia have not been conducted. This study was aimed to assess the soil erosion of Mongolia at a national scale and also to predict future soil erosion that may occur due to climate change. Assessment of soil erosion rates calculated using the Revised Universal Soil Loss Equation (RUSLE) model in the Geographic Information System (GIS) environment. The RUSLE model reflects geographic and climatic characteristics according to the location of the study area, which influencing factors for soil erosion and is aimed at a wide area such as the Mongolian territory. For running the RUSLE model, Climatologies at high resolution for the earth's land surface areas (CHELSA) data, Representative Concentration Pathway (RCP) 8.5 scenario, Food and Agriculture Organization (FAO) soil grid data, European Space Agency (ESA) land cover map, Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) data was used. The results derived from the model are the evaluation of soil erosion using historical data from 1993 and 2013, and predictions for soil erosion in 2050 and 2070 under the RCP 8.5 scenario. Soil erosion rate was divided into 6 classes. In Mongolian territory, 78.02% of the area has been classified to very low erosion risk, while 7.07%, 9.37%, 2.59%, 1.57%, and 1.37% have been classified to low, medium, higher than medium, high and very high erosion risk, respectively. The results of soil erosion at the national scale in 2013 were relatively decreased compared to the results in 1993 but tended to increase again in the future predictions of 2050 and 2070. In the national scale results, the areas classified as highest soil erosion risk were three broad areas: Bayankhongor aimag, Uvurkhangai aimag, and Umnugobi aimag. These three large areas located in high mountain ranges and transition regions of the Gobi Desert and Steppe area. There is also the Gobi Gurvansaikhan National Park, which has the highest conservation value in Mongolia. Therefore, this study suggests that the three regions should be considered first in national land use and soil management plans. As a limitation of the study, this study considered only precipitation as an influencing factor of climate change. According to this study, changes in precipitation caused by climate change make desertification progress faster and also affect land cover changes. Therefore, future studies need to apply prediction models of future land cover change. In addition, the results of soil erosion in the three regions classified as high risk grades are the result of considering only future precipitation for the whole country. In order to evaluate the soil management plans at the regional scale, it is necessary to estimate the soil erosion in each region considering various factors such as a land cover change in addition to precipitation. In this study, we estimated soil erosion at the national scale and predicted future soil erosion in 2050 and 2070. The results of the study can be used as basic data for land use and soil management plans at the national scale and can be used to select areas that require urgent management at the national scale.
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Table of Contents
Abstract
Abstract in Korean
Tables of Contents
List of Tables
List of Figures
1. Introduction
1.1. Background and Purpose
1.2. Literature review
2. Methods and Materials
2.1. Study area
2.2. Study method
2.3. Data
3. Results and Discussion
3.1. RUSLE model results
3.1.1. Rainfall erosivity factor (R)
3.1.2. Slope length and steepness factor (LS)
3.1.3. Soil erodibility factor (K)
3.1.4. Cover management factor (C)
3.1.5. Support practice factor (P)
3.2. Prediction results of soil erosion under the RCP 8.5 scenario
3.3. Discussion
4. Conclusion
References
