Leptosols

Leptosols are soils classified in the World Reference Base for Soil Resources (WRB) as having very limited profile development. They are typically shallow or extremely stony, and often lack well-defined A, B, or C horizons. In many Leptosols, bedrock lies at or near the surface, or the soil consists of a thin mineral layer over a lithic or rock-fragment cover. As a result, diagnostic horizons are absent or poorly expressed, and soil depth is a major constraint on plant growth.

Leptosols occur in a wide range of climates and geologies but are especially common on rugged terrain, steep slopes, and landscapes where erosion or slow weathering limits soil development. They can be rocky, gravelly, or skeletal soils, with organic matter content varying with vegetation cover.

Management and uses: due to shallow depth and limited horizon development, Leptosols are generally not suitable for conventional arable farming without significant soil improvement. They may support grazing, hardy grasses, or forestry, and can be important for biodiversity and landscape value. In soil surveys, Leptosols are distinguished from deeper or more strongly developed soils by their stoniness and lack of horizon differentiation.

See also: World Reference Base for Soil Resources; soil classification.