| 研究生: |
祝福 Dlamini, Sibusiso Bongani |
|---|---|
| 論文名稱: |
評估 SMAP 推導之土壤水分指數與 Eswatini(史瓦帝尼)乾旱監測系統 在農業乾旱監測中的一致性 Evaluating the Consistency of SMAP-Derived Soil Moisture Index with the Eswatini Drought Monitoring System for Agricultural Drought Monitoring. |
| 指導教授: |
羅偉誠
Lo, Wei-Cheng |
| 學位類別: |
碩士 Master |
| 系所名稱: |
工學院 - 自然災害減災及管理國際碩士學位學程 International Master Program on Natural Hazards Mitigation and Management |
| 論文出版年: | 2026 |
| 畢業學年度: | 114 |
| 語文別: | 英文 |
| 論文頁數: | 91 |
| 外文關鍵詞: | Soil moisture, SMAP, drought monitoring, standardized soil moisture index, Eswatini |
| 相關次數: | 點閱:6 下載:0 |
| 分享至: |
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Soil moisture is a key climate variable and an important indicator of agricultural drought, yet satellite estimates remain uncertain at field scale in semi-arid, data-scarce regions such as Eswatini’s Lowveld. This study evaluated the ability of NASA’s SMAP Level-4 soil moisture product to represent field-scale soil moisture variability and support drought monitoring in Nkilongo Inkhundla (constituency), using a decade-long in situ observations and the Composite Drought Indicator (CDI). Multi-depth capacitance probes at four sites provided soil moisture measurements at 100, 200, 300, 400, 600, and 800 mm depths from 2015 to 2025. Missing data were reconstructed using Random Forest regression, which performed best in the mid-root-zone and less consistently at shallower and deeper layers. Monthly in situ and SMAP soil moisture series were then used to derive anomalies, standardized soil moisture indices (SSMI), and drought classes. SMAP and in situ anomalies showed weak to moderate agreement, while SSMI values showed stronger correspondence and moderate categorical agreement. Comparison of SMAP root-zone SSMI with CDI showed over 50% exact agreement and more than 80% agreement within one drought class, with a significant negative correlation. Overall, the findings show that SMAP Level-4 root-zone soil moisture can complement CDI and improve drought monitoring and early warning in Eswatini when used together with field observations.
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