Digital soil mapping of nitrogen, phosphorus, potassium, organic carbon and their crop response thresholds in smallholder managed escarpments of Malawi

This study demonstrates how to predict and map soils within smallholder farms in fragile landscapes of Malawi. We used random forest algorithm and sentinel imagery to improve mapping of SOC and NPK farm level. SOC was predicted by bare soil reflectance, N: vegetation, P: topography, K is indiscrete. Our soil digital mapping revealed SOC & NPK stoichiometric thresholds at scale for small-farm management.