Gasmi A. auteur aut IRD Gomez Cécile auteur aut IRD Lagacherie P. auteur aut IRD Zouari H. auteur aut IRD Laamrani A. auteur aut IRD Chehbouni Abdelghani auteur aut IRD text journalArticle eng text/pdf born digital access Visible, near-infrared and short wave infrared (VNIR/SWIR, 400-2500 nm) remote sensing imagery is a useful tool for topsoil property mapping, but limited to bare soils pixels. With the increasing amount of freely available VNIR/SWIR satellite imagery (e.g. Landsat TM, ETM+, OLI and Sentinel-2A/B), extensive time series data can be exploited to increase the spatial coverage of bare soil derived information. The objective of this study was to evaluate the benefits of using a bare soil image created from the mean spectral reflectance from bare soil pixels along a time series, compared to a single-date image. The benefits were analyzed in term of (i) proportion of soil mapping and (ii) accuracy of clay content prediction. The study was conducted over the Cap-Bon region (Northern Tunisia) which is a pedologically contrasted and cultivated area. To this end, 262 topsoil samples and three Landsat-TM images acquired during the summer season were used. Multiple linear regression (MLR) models based on the multi-date and single-date Landsat-derived spectral dataset were performed to quantify clay soil content. Our results have shown that (1) a bare soil image created from only mean spectral reflectance from common bare soil pixels along a time series provided the best accuracy of clay content prediction (i.e., coefficient of determination of validation (R-val(2)) of 0.75, a root mean square error of prediction (RMSEP) of 88 g/kg) with a moderate bare soil coverage (i.e., 23% of the study area); (2) a bare soil image created from a mix of mean spectral reflectance from common bare soil pixels along a time series and of spectral reflectance from bare soil pixels of single-date images provided acceptable accuracy of clay content prediction (i.e., R-val(2) = 0.64, RMSEP = 109 g/kg) with a relatively high bare soil coverage (i.e., 44% of the study area); and (3) all the bare soil images provided similar spatial structures of the clay content predictions. With the actual availability of the VNIR/SWIR satellite imagery for the entire globe, this study offer a simple and accurate method for delivering accurate soil property maps over large areas, to the geoscience community. specialized Multi-Date imagery Landsat-TM Bare soil coverage Soil day mapping MLR Prediction accuracy TUNISIE CAP BON 068 126 388 114864 [12 p.] 2021 0016-7061 https://www.documentation.ird.fr/hor/fdi:010081038 10.1016/j.geoderma.2020.114864 0016-7061 [F B010081038] https://www.documentation.ird.fr/hor/fdi:010081038 https://www.documentation.ird.fr/intranet/publi/2021/03/010081038.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2021-04-01 2025-02-24 fdi:010081038 fre