Week 4 Textbook Readings: Weathering and Soil Science Flashcards
Acid rain
Precipitation high in sulfuric acid and nitric acid from reactions between water vapor and sulfur and nitrogen oxides in the atmosphere
Parent material
The underlying rock material from which the inorganic components of a soil are derived
Horizon
A horizontal layer in a soil defined by distinctive physical features such as texture and color
Soil degradation
The loss of some or all of a soil’s ability to support plant growth
Erosion
The physical removal of rock fragments from a landscape or ecosystem
Humus
The most fully decomposed organic matter in the lowest section of the O horizon
O horizon
The organic horizon at the surface of many soils, composed of organic detritus in various stages of decomposition
A horizon
Frequently the top layer of soil, a zone of organic material and minerals that have been mixed together. Also known as topsoil.
E horizon
A zone of leaching, or eluviation, found in some acidic soils under the O horizon, or less often, the A horizon
B horizon
A soil horizon composed primarily of mineral material with very little organic matter
C horizon
The least weathered soil horizon, which always occurs beneath the B horizon and is similar to the parent material.
Cation exchange capacity (CEC)
The ability of a particular soil to adsorb and release cations
Base saturation
The proportion of soil bases to soil acids, expressed as a percentage
