Soil Profile

**Soil horizons** represent the structure of soil according to is chemical and physical features. We recognize these 5 types:

**O horizon** is created by at least 20% of organic matter. According to its decomposition state, we can identify sapric (highly), hemic (moderately) and fibric (minimally decayed).

**A horizon** represents a mineral structure of the soil. It is the upmost layer of the soil, referred also as topsoil. It is full of organic matter which has decayed, which explain its darker colour.

**B horizon** is typical for its transformations, such as chemical variation of a clay composition, and additions in the form of soil enrichment. Most common materials are clay, iron and soluble salts.

**C horizon** is created by parent materials (weathered minerals forming particles of a soil). No dominant processes happen here, loses and additions of soluble material (e.g. salts) are scarce.

**R horizon** is a bedrock.

## Keywords
crust pedosphere pedology soil horizon earth