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EARTH SCIENCE > LAND SURFACE > SOILS > SOIL HORIZONS/PROFILE

Definition:
The soil profile is the vertical section of the soil, from the surface through all its horizons, where a horizon is a layer of soil, approximately parallel to the soil surface, differing in properties and characteristics from adjacent layers below and above it.

Reference:
The Nature and Properties of Soils, Prentice Hall, 1996.