So, what is soil? The USDA has this to say:
Soil is a natural body comprised of solids (minerals and organic matter), liquid, and gases that occurs on the land surface, occupies space, and is characterized by one or both of the following: horizons, or layers, that are distinguishable from the initial material as a result of additions, losses, transfers, and transformations of energy and matter or the ability to support rooted plants in a natural environment.
Lengthy definition, that. But reading closely, soil has many things in it: nutrients; minerals; dead, decayed stuff; water and other liquids; and air and other gases.
And–surprise?–soil has horizons just like the atmosphere and each is easily identifiable from the other.