What are soil horizons?
As you drive along highways, you are likely to pass places where the roadway cuts through soil. Have you noticed layers in these road cuts? During soil formation, inorganic materials (e.g., minerals) and organic materials (e.g., decaying plants and animals) are transformed and, with the flow of water through the soil, settle downward which creates layers called soil horizons. An established method for describing soil horizons labels them, form the surface down, O, A, E, B, C, and R. There can, however, be subdivisions of the major horizons in some soil profiles. Also, not all of the soil horizons are represented in any given location; the presence or absence of these layers helps to classify soil types. Soils have different and unique profiles depending on a number of factors, including: climate, organisms, parent material, topography, and time. What are the characteristics of different soil horizons? O Horizon: The O, or organic, horizon is found in soils formed under forest vegetatio
