{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T16:07:29Z","timestamp":1781539649768,"version":"3.54.5"},"reference-count":75,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2023,11,23]],"date-time":"2023-11-23T00:00:00Z","timestamp":1700697600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004901","name":"Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado de Minas Gerai (FAPEMIG)","doi-asserted-by":"publisher","award":["APQ-01562-23"],"award-info":[{"award-number":["APQ-01562-23"]}],"id":[{"id":"10.13039\/501100004901","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004901","name":"Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado de Minas Gerai (FAPEMIG)","doi-asserted-by":"publisher","award":["001"],"award-info":[{"award-number":["001"]}],"id":[{"id":"10.13039\/501100004901","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002322","name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento Pessoal de N\u00edvel Superior (CAPES)","doi-asserted-by":"publisher","award":["APQ-01562-23"],"award-info":[{"award-number":["APQ-01562-23"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002322","name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento Pessoal de N\u00edvel Superior (CAPES)","doi-asserted-by":"publisher","award":["001"],"award-info":[{"award-number":["001"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]},{"name":"CNPq (Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico)","award":["APQ-01562-23"],"award-info":[{"award-number":["APQ-01562-23"]}]},{"name":"CNPq (Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico)","award":["001"],"award-info":[{"award-number":["001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Despite optical remote sensing (and the spectral vegetation indices) contributions to digital soil-mapping studies of soil organic carbon (SOC), few studies have used active radar remote sensing mission data like that from synthetic aperture radar (SAR) sensors to predict SOC. Bearing in mind the importance of SOC mapping for agricultural, ecological, and climate interests and also the recently developed methods for vegetation monitoring using Sentinel-1 SAR data, in this work, we aimed to take advantage of the high operationality of Sentinel-1 imaging to test the accuracy of SOC prediction at different soil depths using machine learning systems. Using linear, nonlinear, and tree regression-based methods, it was possible to predict the SOC content of soils from western Bahia, Brazil, a region with predominantly sandy soils, using as explanatory variables the SAR vegetation indices. The models fed with SAR sensor polarizations and vegetation indices produced more accurate results for the topsoil layers (0\u20135 cm and 5\u201310 cm in depth). In these superficial layers, the models achieved an RMSE in the order of 5.0 g kg\u22121 and an R2 ranging from 0.16 to 0.24, therefore explaining about 20% of SOC variability using only Sentinel-1 predictors.<\/jats:p>","DOI":"10.3390\/rs15235464","type":"journal-article","created":{"date-parts":[[2023,11,23]],"date-time":"2023-11-23T03:45:56Z","timestamp":1700711156000},"page":"5464","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Sentinel-1 Imagery Used for Estimation of Soil Organic Carbon by Dual-Polarization SAR Vegetation Indices"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4888-906X","authenticated-orcid":false,"given":"Erli Pinto dos","family":"Santos","sequence":"first","affiliation":[{"name":"Department of Agricultural Engineering, Federal University of Vi\u00e7osa, University Campus, Peter Henry Rolfs Avenue, Vi\u00e7osa 36570-900, MG, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michel Castro","family":"Moreira","sequence":"additional","affiliation":[{"name":"Department of Agricultural Engineering, Federal University of Vi\u00e7osa, University Campus, Peter Henry Rolfs Avenue, Vi\u00e7osa 36570-900, MG, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9484-1411","authenticated-orcid":false,"given":"Elp\u00eddio In\u00e1cio","family":"Fernandes-Filho","sequence":"additional","affiliation":[{"name":"Department of Soil, Federal University of Vi\u00e7osa, University Campus, Peter Henry Rolfs Avenue, Vi\u00e7osa 36570-900, MG, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5328-0323","authenticated-orcid":false,"given":"Jos\u00e9 Alexandre M.","family":"Dematt\u00ea","sequence":"additional","affiliation":[{"name":"Department of Soil Science, \u201cLuiz de Queiroz\u201d College of Agriculture, University of S\u00e3o Paulo, P\u00e1dua Dias Avenue, Piracicaba 13418-900, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1925-1809","authenticated-orcid":false,"given":"Emily Ane","family":"Dionizio","sequence":"additional","affiliation":[{"name":"Department of Agricultural Engineering, Federal University of Vi\u00e7osa, University Campus, Peter Henry Rolfs Avenue, Vi\u00e7osa 36570-900, MG, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9666-7421","authenticated-orcid":false,"given":"Demetrius David da","family":"Silva","sequence":"additional","affiliation":[{"name":"Department of Agricultural Engineering, Federal University of Vi\u00e7osa, University Campus, Peter Henry Rolfs Avenue, Vi\u00e7osa 36570-900, MG, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Renata Ranielly Pedroza","family":"Cruz","sequence":"additional","affiliation":[{"name":"Department of Agronomy, Federal University of Vi\u00e7osa, University Campus, Peter Henry Rolfs Avenue, Vi\u00e7osa 36570-900, MG, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean Michel","family":"Moura-Bueno","sequence":"additional","affiliation":[{"name":"Soil Science Department, Federal University of Santa Maria, Roraima Avenue, 1000, Santa Maria 97105-900, RS, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0884-254X","authenticated-orcid":false,"given":"Uemeson Jos\u00e9 dos","family":"Santos","sequence":"additional","affiliation":[{"name":"Federal Institute of Education, Science, and Technology of Par\u00e1, Campus \u00d3bidos, Rodovia PA 437, km 02, \u00d3bidos 68250-000, PA, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6874-9315","authenticated-orcid":false,"given":"Marcos Heil","family":"Costa","sequence":"additional","affiliation":[{"name":"Department of Agricultural Engineering, Federal University of Vi\u00e7osa, University Campus, Peter Henry Rolfs Avenue, Vi\u00e7osa 36570-900, MG, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1016\/j.geoderma.2017.12.011","article-title":"Modeling Soil Organic Carbon with Quantile Regression: Dissecting Predictors\u2019 Effects on Carbon Stocks","volume":"318","author":"Lombardo","year":"2018","journal-title":"Geoderma"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1016\/bs.agron.2019.07.004","article-title":"Soil Organic Carbon in Sandy Soils: A Review","volume":"Volume 158","author":"Yost","year":"2019","journal-title":"Advances in Agronomy"},{"key":"ref_3","unstructured":"FAO, and ITPS (2020). 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