Nation-wide open soil property maps of up to 100 cm depth for Sri Lanka

This dataset contains interpolated maps for 9 soil properties; pH, bulk density (gcm-3), cation exchange capacity (cmol+ kg–1), organic carbon content (%), volumetric moisture content (VMC) at 0.33 bars level (drainage upper limit – mm mm-1), VMC at 15 bars level (wilting point – mm mm-1), clay (%), sand (%) and silt content (%). The data are available at 5 different depths as 0-5 cm, 5-15 cm, 15-30 cm, 30-60 cm and 60-100 cm.

Observed data from 122 locations that were distributed throughout the country were used for interpolation mapping. The choice of interpolation method can generate different results, therefore several interpolation methods were used in the interpolation process. The least Root Mean Square Error (RMSE), through the process of cross-validation or leaving-one-out of determined the final method used for mapping each property.