Present global maps of soil water retention(SWR)are mostly derived from pedotransfer functions(PTFs)applied to maps of other basic soil *** an alternative,'point-based'mapping of soil water content can improve global ...
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Present global maps of soil water retention(SWR)are mostly derived from pedotransfer functions(PTFs)applied to maps of other basic soil *** an alternative,'point-based'mapping of soil water content can improve global soil data availability and *** developed point-based global maps with estimated uncertainty of the volumetric SWR at 100,330 and 15000 cm suction using measured SWR data extracted from the WoSIS Soil Profile Database together with data estimated by a random forest PTF(PTF-RF).The point data was combined with around 200 environmental covariates describing vegetation,terrain morphology,climate,geology,and hydrology using *** total,we used 7292,33192 and 42016 SWR point observations at 100,330 and 15000 cm,respectively,and complemented the dataset with 436108 estimated values at each *** cross-validation yielded a Root Mean Square Error(RMSE)of6380,7.112 and 6.48510^(-2)cm^(3)cm^(-3),and a Model Efficiency Coefficient(MEC)of0.430,0386,and 0.471,respectively,for 100,330 and 15000 *** results were also compared to three published global maps of SWR to evaluate differences between point-based and map-based mapping ***-based mapping performed better than the three map-based mapping approaches for 330 and 15000 cm,while for 100 cm results were similar,possibly due to the limited number of SWR observa-tions for 100 *** sources or uncertainty identified included the geographical clustering of the data and the limitation of the covariates to represent the naturally high variation of SWR.
Digital maps of soil properties are now widely ***-users now can access several digital soil mapping(DSM)products of soil properties,produced using different models,calibration/training data,and covariates at various ...
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Digital maps of soil properties are now widely ***-users now can access several digital soil mapping(DSM)products of soil properties,produced using different models,calibration/training data,and covariates at various spatial scales from global to ***,there is an urgent need to provide easy-to-understand tools to communicate map uncertainty and help end-users assess the reliability of DSM products for use at local *** this study,we used a large amount of hand-feel soil texture(HFST)data to assess the performance of various published DSM products on the prediction of soil particle size distribution in Central *** tested four DSM products for soil texture prediction developed at various scales(global,continental,national,and regional)by comparing their predictions with approximately 3200 HFST observations realized on a 1:50000 soil survey conducted after release of these DSM *** used both visual comparisons and quantitative indicators to match the DSM predictions and HFST *** comparison between the low-cost HFST observations and DSM predictions clearly showed the applicability of various DSM products,with the prediction accuracy increasing from global to regional *** simple evaluation can determine which products can be used at the local scale and if more accurate DSM products are required.
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