iSDAsoil: soil silt content (USDA system) for Africa predicted at 30 m resolution at 0-20 and 20-50 cm depths (Q6688911)

iSDAsoil dataset soil silt content in % predicted at 30 m resolution for 020 and 2050 cm depth intervals. Data has been projected in WGS84 coordinate system and compiled as COG.Predictions have been generated using multi-scale Ensemble Machine Learning with 250 m (MODIS, PROBA-V, climatic variables and similar) and 30 m (DTM derivatives, Landsat, Sentinel-2 and similar) resolution covariates. For model training we use a pan-African compilations of soil samples and profiles (iSDA points, AfSPDB, LandPKS, and other national and regional soil datasets). Cite as: Hengl, T., Miller, M.A.E., Križan, J.et al.African soil properties and nutrients mapped at 30m spatial resolution using two-scale ensemble machine learning.Sci Rep11,6130 (2021). https://doi.org/10.1038/s41598-021-85639-y To open the maps in QGIS and/or directly compute with them, please use the Cloud-Optimized GeoTIFF version. Layer description: sol_silt_tot_psa_mehlich3_m_30m_*..*cm_2001..2017_v0.13_wgs84.tif = predicted soil silt content mean value, sol_silt_tot_psa_mehlich3_md_30m_*..*cm_2001..2017_v0.13_wgs84.tif = predicted soil silt content model (prediction) errors, Model errors were derived using bootstrapping: md is derived as standard deviation of individual learners from 5-fold cross-validation (using spatial blocking). The model 5-fold cross-validation (mlr::makeStackedLearner) for this variable indicates: Variable: silt_tot_psa R-square: 0.64 Fitted values sd: 11.9 RMSE: 8.92 Random forest model: Call: stats::lm(formula = f, data = d) Residuals: Min 1Q Median 3Q Max -63.746 -3.631 -0.526 2.630 72.486 Coefficients: Estimate Std. Error t value Pr(|t|) (Intercept) -35.876865 36.887592 -0.973 0.331 regr.ranger 0.948111 0.003874 244.733 2e-16 *** regr.xgboost 0.062717 0.005506 11.391 2e-16 *** regr.cubist 0.025705 0.004747 5.415 6.14e-08 *** regr.nnet 1.902142 1.968248 0.966 0.334 regr.cvglmnet -0.028579 0.005799 -4.928 8.32e-07 *** --- Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 Residual standard error: 8.915 on 122223 degrees of freedom Multiple R-squared: 0.6399, Adjusted R-squared: 0.6399 F-statistic: 4.344e+04 on 5 and 122223 DF, p-value: 2.2e-16 To submit an issue or request support please visit https://isda-africa.com/isdasoil