{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T05:23:33Z","timestamp":1776835413014,"version":"3.51.2"},"reference-count":54,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2015,7,13]],"date-time":"2015-07-13T00:00:00Z","timestamp":1436745600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008845","name":"Xinjiang University","doi-asserted-by":"publisher","award":["XJUBSCX-2013012"],"award-info":[{"award-number":["XJUBSCX-2013012"]}],"id":[{"id":"10.13039\/501100008845","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008845","name":"Xinjiang University","doi-asserted-by":"publisher","award":["XJDX0201-2013-06"],"award-info":[{"award-number":["XJDX0201-2013-06"]}],"id":[{"id":"10.13039\/501100008845","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U1138303"],"award-info":[{"award-number":["U1138303"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41130531"],"award-info":[{"award-number":["41130531"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Soil salinization is one of the most widespread soil degradation processes on Earth, especially in arid and semi-arid areas. The salinized soil in arid to semi-arid Xinjiang Uyghur Autonomous Region in China accounts for 31% of the area of cultivated land, and thus it is pivotal for the sustainable agricultural development of the area to identify reliable and cost-effective methodologies to monitor the spatial and temporal variations in soil salinity. This objective was accomplished over the study area (Keriya River Basin, northwestern China) by adopting technologies that heavily rely on, and integrate information contained in, a readily available suite of remote sensing datasets. The following procedures were conducted: (1) a selective principle component analysis (S-PCA) fusion image was generated using Phased Array Type L-band SAR (PALSAR) backscattering coefficient (\u03c3\u00b0) and Landsat Enhanced Thematic Mapper Plus (ETM+) multispectral image of Keriya River Basin; and (2) a support vector machines (SVM) classification method was employed to classify land cover types with a focus on mapping salinized soils; (3) a cross-validation method was adopted to identify the optimum classification parameters, and obtain an optimal SVM classification model; (4) Radarsat-2 (C band) and PALSAR polarimetric images were used to analyze polarimetric backscattering behaviors in relation to the variation in soil salinization; (5) a decision tree (DT) scheme for multi-source optical and polarimetric SAR data integration was proposed to improve the estimation and monitoring accuracies of soil salinization; and (6) detailed field observations and ground truthing were used for validation of the adopted methodology, and quantity and allocation disagreement measures were applied to assess classification outcome. Results showed that the fusion of passive reflective and active microwave remote sensing data provided an effective tool in detecting soil salinization. Overall accuracy of the adopted SVM classifier with optimal parameters for fused image of ETM+ and PALSAR data was 91.25% with a Kappa coefficient of 0.89, which was further improved by the DT data integration and classification method yielding an accuracy of 93.01% with a Kappa coefficient of 0.92 and lower disagreement of quantity and allocation.<\/jats:p>","DOI":"10.3390\/rs70708803","type":"journal-article","created":{"date-parts":[[2015,7,13]],"date-time":"2015-07-13T10:38:10Z","timestamp":1436783890000},"page":"8803-8829","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":55,"title":["Monitoring Soil Salinization in Keriya River Basin, Northwestern China Using Passive Reflective and Active Microwave Remote Sensing Data"],"prefix":"10.3390","volume":"7","author":[{"given":"Ilyas","family":"Nurmemet","sequence":"first","affiliation":[{"name":"Ministry of Education Key Laboratory of Oasis Ecology and College of Resources and Environmental Sciences, Xinjiang University, Urumqi 830046, China"},{"name":"Department of Geosciences, Western Michigan University, Kalamazoo, MI 49008, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abduwasit","family":"Ghulam","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of Oasis Ecology and College of Resources and Environmental Sciences, Xinjiang University, Urumqi 830046, China"},{"name":"Center for Sustainability, Saint Louis University, St. Louis, MO 63108, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tashpolat","family":"Tiyip","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of Oasis Ecology and College of Resources and Environmental Sciences, Xinjiang University, Urumqi 830046, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Racha","family":"Elkadiri","sequence":"additional","affiliation":[{"name":"Department of Geosciences, Western Michigan University, Kalamazoo, MI 49008, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jian-Li","family":"Ding","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of Oasis Ecology and College of Resources and Environmental Sciences, Xinjiang University, Urumqi 830046, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4241-6181","authenticated-orcid":false,"given":"Matthew","family":"Maimaitiyiming","sequence":"additional","affiliation":[{"name":"Center for Sustainability, Saint Louis University, St. Louis, MO 63108, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abdulla","family":"Abliz","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of Oasis Ecology and College of Resources and Environmental Sciences, Xinjiang University, Urumqi 830046, China"},{"name":"Applied Physical Geography, Catholic University of Eichst\u00e4tt-Ingolstadt, Eichst\u00e4tt 85071, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mamat","family":"Sawut","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of Oasis Ecology and College of Resources and Environmental Sciences, Xinjiang University, Urumqi 830046, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fei","family":"Zhang","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of Oasis Ecology and College of Resources and Environmental Sciences, Xinjiang University, Urumqi 830046, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abdugheni","family":"Abliz","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of Oasis Ecology and College of Resources and Environmental Sciences, Xinjiang University, Urumqi 830046, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qian","family":"Sun","sequence":"additional","affiliation":[{"name":"Ministry of Education Key Laboratory of Oasis Ecology and College of Resources and Environmental Sciences, Xinjiang University, Urumqi 830046, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,7,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"191","DOI":"10.1016\/j.geoderma.2005.02.003","article-title":"Assessing salt-affected soils using remote sensing, solute modelling, and geophysics","volume":"130","author":"Farifteh","year":"2006","journal-title":"Geoderma"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0034-4257(02)00188-8","article-title":"Remote sensing of soil salinity: Potentials and constraints","volume":"85","author":"Metternicht","year":"2003","journal-title":"Remote Sens. 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