date: 2022-06-18T09:22:49Z pdf:PDFVersion: 1.7 pdf:docinfo:title: Satellite Imagery to Map Topsoil Organic Carbon Content over Cultivated Areas: An Overview xmp:CreatorTool: LaTeX with hyperref Keywords: soil organic carbon; spectral models; satellite imagery access_permission:modify_annotations: true access_permission:can_print_degraded: true subject: There is a need to update soil maps and monitor soil organic carbon (SOC) in the upper horizons or plough layer for enabling decision support and land management, while complying with several policies, especially those favoring soil carbon storage. This review paper is dedicated to the satellite-based spectral approaches for SOC assessment that have been achieved from several satellite sensors, study scales and geographical contexts in the past decade. Most approaches relying on pure spectral models have been carried out since 2019 and have dealt with temperate croplands in Europe, China and North America at the scale of small regions, of some hundreds of km2: dry combustion and wet oxidation were the analytical determination methods used for 50% and 35% of the satellite-derived SOC studies, for which measured topsoil SOC contents mainly referred to mineral soils, typically cambisols and luvisols and to a lesser extent, regosols, leptosols, stagnosols and chernozems, with annual cropping systems with a SOC value of ~15 gkg-1 and a range of 30 gkg-1 in median. Most satellite-derived SOC spectral prediction models used limited preprocessing and were based on bare soil pixel retrieval after Normalized Difference Vegetation Index (NDVI) thresholding. About one third of these models used partial least squares regression (PLSR), while another third used random forest (RF), and the remaining included machine learning methods such as support vector machine (SVM). We did not find any studies either on deep learning methods or on all-performance evaluations and uncertainty analysis of spatial model predictions. Nevertheless, the literature examined here identifies satellite-based spectral information, especially derived under bare soil conditions, as an interesting approach that deserves further investigations. Future research includes considering the simultaneous analysis of imagery acquired at several dates i.e., temporal mosaicking, testing the influence of possible disturbing factors and mitigating their effects fusing mixed models incorporating non-spectral ancillary information. dc:creator: Emmanuelle Vaudour, Asa Gholizadeh, Fabio Castaldi, Mohammadmehdi Saberioon, Lubo? Bor?vka, Diego Urbina-Salazar, Youssef Fouad, Dominique Arrouays, Anne C. Richer-de-Forges, James Biney, Johanna Wetterlind and Bas Van Wesemael dcterms:created: 2022-06-18T09:16:12Z Last-Modified: 2022-06-18T09:22:49Z dcterms:modified: 2022-06-18T09:22:49Z dc:format: application/pdf; version=1.7 title: Satellite Imagery to Map Topsoil Organic Carbon Content over Cultivated Areas: An Overview Last-Save-Date: 2022-06-18T09:22:49Z pdf:docinfo:creator_tool: LaTeX with hyperref access_permission:fill_in_form: true pdf:docinfo:keywords: soil organic carbon; spectral models; satellite imagery pdf:docinfo:modified: 2022-06-18T09:22:49Z meta:save-date: 2022-06-18T09:22:49Z pdf:encrypted: false dc:title: Satellite Imagery to Map Topsoil Organic Carbon Content over Cultivated Areas: An Overview modified: 2022-06-18T09:22:49Z cp:subject: There is a need to update soil maps and monitor soil organic carbon (SOC) in the upper horizons or plough layer for enabling decision support and land management, while complying with several policies, especially those favoring soil carbon storage. This review paper is dedicated to the satellite-based spectral approaches for SOC assessment that have been achieved from several satellite sensors, study scales and geographical contexts in the past decade. Most approaches relying on pure spectral models have been carried out since 2019 and have dealt with temperate croplands in Europe, China and North America at the scale of small regions, of some hundreds of km2: dry combustion and wet oxidation were the analytical determination methods used for 50% and 35% of the satellite-derived SOC studies, for which measured topsoil SOC contents mainly referred to mineral soils, typically cambisols and luvisols and to a lesser extent, regosols, leptosols, stagnosols and chernozems, with annual cropping systems with a SOC value of ~15 gkg-1 and a range of 30 gkg-1 in median. Most satellite-derived SOC spectral prediction models used limited preprocessing and were based on bare soil pixel retrieval after Normalized Difference Vegetation Index (NDVI) thresholding. About one third of these models used partial least squares regression (PLSR), while another third used random forest (RF), and the remaining included machine learning methods such as support vector machine (SVM). We did not find any studies either on deep learning methods or on all-performance evaluations and uncertainty analysis of spatial model predictions. Nevertheless, the literature examined here identifies satellite-based spectral information, especially derived under bare soil conditions, as an interesting approach that deserves further investigations. Future research includes considering the simultaneous analysis of imagery acquired at several dates i.e., temporal mosaicking, testing the influence of possible disturbing factors and mitigating their effects fusing mixed models incorporating non-spectral ancillary information. pdf:docinfo:subject: There is a need to update soil maps and monitor soil organic carbon (SOC) in the upper horizons or plough layer for enabling decision support and land management, while complying with several policies, especially those favoring soil carbon storage. This review paper is dedicated to the satellite-based spectral approaches for SOC assessment that have been achieved from several satellite sensors, study scales and geographical contexts in the past decade. Most approaches relying on pure spectral models have been carried out since 2019 and have dealt with temperate croplands in Europe, China and North America at the scale of small regions, of some hundreds of km2: dry combustion and wet oxidation were the analytical determination methods used for 50% and 35% of the satellite-derived SOC studies, for which measured topsoil SOC contents mainly referred to mineral soils, typically cambisols and luvisols and to a lesser extent, regosols, leptosols, stagnosols and chernozems, with annual cropping systems with a SOC value of ~15 gkg-1 and a range of 30 gkg-1 in median. Most satellite-derived SOC spectral prediction models used limited preprocessing and were based on bare soil pixel retrieval after Normalized Difference Vegetation Index (NDVI) thresholding. About one third of these models used partial least squares regression (PLSR), while another third used random forest (RF), and the remaining included machine learning methods such as support vector machine (SVM). We did not find any studies either on deep learning methods or on all-performance evaluations and uncertainty analysis of spatial model predictions. Nevertheless, the literature examined here identifies satellite-based spectral information, especially derived under bare soil conditions, as an interesting approach that deserves further investigations. Future research includes considering the simultaneous analysis of imagery acquired at several dates i.e., temporal mosaicking, testing the influence of possible disturbing factors and mitigating their effects fusing mixed models incorporating non-spectral ancillary information. Content-Type: application/pdf pdf:docinfo:creator: Emmanuelle Vaudour, Asa Gholizadeh, Fabio Castaldi, Mohammadmehdi Saberioon, Lubo? Bor?vka, Diego Urbina-Salazar, Youssef Fouad, Dominique Arrouays, Anne C. Richer-de-Forges, James Biney, Johanna Wetterlind and Bas Van Wesemael X-Parsed-By: org.apache.tika.parser.DefaultParser creator: Emmanuelle Vaudour, Asa Gholizadeh, Fabio Castaldi, Mohammadmehdi Saberioon, Lubo? Bor?vka, Diego Urbina-Salazar, Youssef Fouad, Dominique Arrouays, Anne C. Richer-de-Forges, James Biney, Johanna Wetterlind and Bas Van Wesemael meta:author: Emmanuelle Vaudour, Asa Gholizadeh, Fabio Castaldi, Mohammadmehdi Saberioon, Lubo? Bor?vka, Diego Urbina-Salazar, Youssef Fouad, Dominique Arrouays, Anne C. Richer-de-Forges, James Biney, Johanna Wetterlind and Bas Van Wesemael dc:subject: soil organic carbon; spectral models; satellite imagery meta:creation-date: 2022-06-18T09:16:12Z created: Sat Jun 18 11:16:12 CEST 2022 access_permission:extract_for_accessibility: true access_permission:assemble_document: true xmpTPg:NPages: 22 Creation-Date: 2022-06-18T09:16:12Z access_permission:extract_content: true access_permission:can_print: true meta:keyword: soil organic carbon; spectral models; satellite imagery Author: Emmanuelle Vaudour, Asa Gholizadeh, Fabio Castaldi, Mohammadmehdi Saberioon, Lubo? Bor?vka, Diego Urbina-Salazar, Youssef Fouad, Dominique Arrouays, Anne C. Richer-de-Forges, James Biney, Johanna Wetterlind and Bas Van Wesemael producer: pdfTeX-1.40.21 access_permission:can_modify: true pdf:docinfo:producer: pdfTeX-1.40.21 pdf:docinfo:created: 2022-06-18T09:16:12Z