The soil found in hot desserts is called aridisol. In short the soil found in desserts are pooor in organic matter and rich in salts.
On of the main climatic factors affecting soil is the lack of rainfall. Lack of moisture leads to thin soils as the weathering of the surrounding rock is slow. The lack of rainfall limits the amount of vegetation that can grow which leads to very low amounts of organic matter in the soil. Slow decompostiion (which is also a result of sparse vegetation and low amounts of rain) in the arid area also makes the organic content of the soil low . Salt crusts ,form on desert soils due to high temperatures and limited rainfall which lad to evapotranspiration exceeding precipiation and the upward movement on salts.