{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T08:47:21Z","timestamp":1775033241036,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2024,1,3]],"date-time":"2024-01-03T00:00:00Z","timestamp":1704240000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Three Gorges Follow-up Work \u201cRemote Sensing Investigation and Evaluation of Flood Control Safety in the Three Gorges Section\u201d","award":["JZ0161A012023"],"award-info":[{"award-number":["JZ0161A012023"]}]},{"name":"Three Gorges Follow-up Work \u201cRemote Sensing Investigation and Evaluation of Flood Control Safety in the Three Gorges Section\u201d","award":["20212BBG71008"],"award-info":[{"award-number":["20212BBG71008"]}]},{"name":"Youth Innovation Talents Promotion Plan of the Research Center of Flood and Drought Disaster Reduction of the Ministry of Water Resources","award":["JZ0161A012023"],"award-info":[{"award-number":["JZ0161A012023"]}]},{"name":"Youth Innovation Talents Promotion Plan of the Research Center of Flood and Drought Disaster Reduction of the Ministry of Water Resources","award":["20212BBG71008"],"award-info":[{"award-number":["20212BBG71008"]}]},{"name":"Key Research and Development Program of Jiang Xi Province","award":["JZ0161A012023"],"award-info":[{"award-number":["JZ0161A012023"]}]},{"name":"Key Research and Development Program of Jiang Xi Province","award":["20212BBG71008"],"award-info":[{"award-number":["20212BBG71008"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Soil moisture (SM) data can provide guidance for decision-makers in fields such as drought monitoring and irrigation management. Soil Moisture Active Passive (SMAP) satellite offers sufficient spatial resolution for global-scale applications, but its utility is limited in regional areas due to its lower spatial resolution. To address this issue, this study proposed a downscaling framework based on the Stacking strategy. The framework integrated extreme gradient boosting (XGBoost), light gradient boosting machine (LightGBM), and categorical boosting (CatBoost) to generate 1 km resolution SM data using 15 high-resolution factors derived from multi-source datasets. In particular, to test the influence of terrain partitioning on downscaling results, Anhui Province, which has diverse terrain features, was selected as the study area. The results indicated that the performance of the three base models varied, and the developed Stacking strategy maximized the potential of each model with encouraging downscaling results. Specifically, we found that: (1) The Stacking model achieved the highest accuracy in all regions, and the performance order of the base models was: XGBoost &gt; CatBoost &gt; LightGBM. (2) Compared with the measured SM at 87 sites, the downscaled SM outperformed other 1 km SM products as well as the downscaled SM without partitioning, with an average ubRMSE of 0.040 m3\/m3. (3) The downscaled SM responded positively to rainfall events and mitigated the systematic bias of SMAP. It also preserved the spatial trend of the original SMAP, with higher levels in the humid region and relatively lower levels in the semi-humid region. Overall, this study provided a new strategy for soil moisture downscaling and revealed some interesting findings related to the effectiveness of the Stacking model and the impact of terrain partitioning on downscaling accuracy.<\/jats:p>","DOI":"10.3390\/rs16010200","type":"journal-article","created":{"date-parts":[[2024,1,3]],"date-time":"2024-01-03T11:31:50Z","timestamp":1704281510000},"page":"200","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["A Spatial Downscaling Framework for SMAP Soil Moisture Based on Stacking Strategy"],"prefix":"10.3390","volume":"16","author":[{"given":"Jiaxin","family":"Xu","sequence":"first","affiliation":[{"name":"Department of Surveying and Mapping, College of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024, China"},{"name":"China Institute of Water Resources and Hydropower Research, Beijing 100038, China"}]},{"given":"Qiaomei","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Surveying and Mapping, College of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024, China"}]},{"given":"Xiaotao","family":"Li","sequence":"additional","affiliation":[{"name":"China Institute of Water Resources and Hydropower Research, Beijing 100038, China"}]},{"given":"Jianwei","family":"Ma","sequence":"additional","affiliation":[{"name":"China Institute of Water Resources and Hydropower Research, Beijing 100038, China"}]},{"given":"Wenlong","family":"Song","sequence":"additional","affiliation":[{"name":"China Institute of Water Resources and Hydropower Research, Beijing 100038, China"}]},{"given":"Lei","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Surveying and Mapping, College of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024, China"}]},{"given":"Xiaoye","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Surveying and Mapping, College of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024, China"},{"name":"China Institute of Water Resources and Hydropower Research, Beijing 100038, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1016\/j.jhydrol.2005.07.003","article-title":"Evidence for intensification of the global water cycle: Review and synthesis","volume":"319","author":"Huntington","year":"2006","journal-title":"J. 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