noun
- the upper layers of soil above the parent material, consisting of the A and B horizons
Usage: geology; soil science
Examples
- The solum in this region extends about three feet below the surface.
- Soil scientists study the solum to understand nutrient distribution.
- The solum contains most of the organic matter and root activity.
- Heavy rainfall can affect the chemical composition of the solum.
- Agricultural productivity depends largely on the health of the solum.