Answer:
the U.S. southwest
Explanation:
Aridosols are desert soils, where plant diversity is very low and often nonexistent. These soils are formed in arid and semi-arid regions, such as those found in the Southwestern United States. These soils occur due to the insufficient amount of precipitation in the region, in addition, due to the low vegetation cover, the rain that falls in the region, manages to leach the soluble salts of the soil, allowing them to drain into the deeper layers of the soil, where they can form carbonate, gypsum or saliferous horizons.