Solum
soil forming conditions. The base of the solum is the relatively unweathered parent material
.
Solum and soils are not synonymous. Some soils include layers that are not affected by soil formation. These layers are not part of the solum. The number of genetic horizons ranges from one to many. A surface layer that is 10 cm thick overlying bedrock can be by itself the solum. A soil that consists only of recently deposited alluvium or recently exposed soft sediment does not have a solum.
In terms of
biological activity
. A solum does not have a maximum or a minimum thickness.
The lower limit should relate to the depth of rooting to be expected for
pedological. Much the same kind of problem exists in some deeply weathered soils in which the deepest material penetrated by roots is very similar to the weathered material at much greater depth.[1]
In Scottish law, the solum is the area of ground that lies inside the walls or foundations of a building.
References
- U.S. Department of Agriculture Handbook 18. Archived from the originalon 2006-02-14. Retrieved 2006-07-02.