B horizon
soil type
Also known as: zone of illuviation
Quick Summary
soil profiles on hillslopes
The thickness and composition of soil horizons vary with position on a hillslope and with water drainage. For example, on the upper slopes of poorly drained profiles, underlying rock may be exposed by surface erosion, and nutrient-rich soils (A horizon) may accumulate at the toeslope. On the other hand, in well-drained profiles under forest cover, the leached layers (E horizon) may be relatively thick and surface erosion minimal.
The B horizon is a subsurface soil layer found directly beneath the A horizon. It is characterized by the accumulation of materials, such as clay, that have been transported from the upper layers through processes like illuviation. Unlike the A horizon, which shows organic matter accumulation, the B horizon typically has less weathering and may exhibit distinct structural features due to the deposited clay. This horizon plays a crucial role in the soil profile, contributing to its unique characteristics and classification.1234
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