AP BIOLOGY

Detailed explanation-1: -Desert soil is mostly sandy soil (90–95%) found in low-rainfall regions. It has a low content of nitrogen and organic matter with very high calcium carbonate and phosphate, thus making it infertile. The amount of calcium is 10 times higher in the lower layer than in the topsoil.

Detailed explanation-2: -Arid soils (or desert soils) are a soil order in USDA soil taxonomy. Aridisols (from the Latin aridus, for “dry", and solum) form in an arid or semi-arid climate. Aridisols dominate the deserts and xeric shrublands, which occupy about one third of the Earth’s land surface.

Detailed explanation-3: -(i) Arid soils are the soils of desert or semi-desert regions and colours varies from red to brown. (ii) The soil has sandy texture and salinity. As precipitation is very low the temperature is high and evaporation is faster making it lack in moisture and humus.

Detailed explanation-4: -Most desert soils are called Aridisols (dry soil). However, in really dry regions of the Sahara and Australian outback, the soil orders are called Entisols. Entisols are new soils, like sand dunes, which are too dry for any major soil horizon development.

Detailed explanation-5: -TROPICAL SOILS | Arid and Semiarid As with arid soils, semiarid soils might have calcic, petrocalcic, duripan, gypsic, natric, and salic horizons. Yet, as with humid soils, semiarid soils might have albic, argillic, and kandic horizons as well as fragipans and plinthite.