We therefore applied the equal-area spline function to the soil components of STATSGO2 map units in order to obtain estimates of soil organic carbon (SOC) content at the GlobalSoilMap standard depth increments. Using these estimates, we calculated the weighted mean of SOC for each STATSGO2 ...
Application of the Equal-Area Spline Function to Legacy Soil Data.Nathan P. Odgers
The results also showed that using additional samples from the top and/or bottom of the soil profiles improved the prediction quality of the spline functions.doi:10.1016/S0016-7061(99)00003-8T.F.A. BishopA.B. McBratneyG.M. Laslett