Quantification of soil loss from eroded soil phases

The effect of accelerated erosion on soils is recorded on US National Cooperative Soil Survey maps as phases of soil series and reflect the percentage of the original A horizon remaining. This definition requires a knowledge of original A horizon thickness prior to cultivation. Erosion classes based on erosion of topsoil underestimate the extent of erosion from both the topsoil and subsoils, particularly where soils have been cultivated for hundreds of years and are severely eroded. For some soils, a major soil classification problem occurs when accelerated erosion affects the diagnostic horizons. -from Authors