In pedogenesis, which process adds materials to the soil profile?

• A. Additions
• B. Losses
• C. Transformations
• D. Translocations

Answer: (A)

Additions involve inputs of material to the soil from outside the system, such as plant litter accumulating on the surface, wind-blown dust and pollen, and atmospheric deposition of salts. These inputs increase the soil’s mass and bring in new material to the profile, which is why this process is described as additions. The other processes deal with different ways material leaves, changes, or moves within the soil: losses remove material through leaching or erosion; transformations chemically or biologically alter existing material; translocations relocate material within the profile (for example, moving clay or organic matter to lower horizons) but don’t add new external material to the soil as a whole.