1.Dry in all parts for more than half of the cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is above 5 °C; and

2.Moist in some or all parts for less than 90 consecutive days when the soil temperature at a depth of 50 cm below the soil surface is above 8 °C.

Soils that have an aridic (torric) soil moisture regime normally occur in areas of arid climates. A few are in areas of semiarid climates and either have physical properties that keep them dry, such as a crusty surface that virtually precludes the infiltration of water, or are on steep slopes where runoff is high. There is little or no leaching in this soil moisture regime, and soluble salts accumulate in the soils if there is a source.

3.4.6 Soil Temperature Regimes

Following is a description of the soil temperature regime identified in Kuwait, which is described as “hyperthermic” and used at the soil family level of Kuwait soil taxonomy hierarchy.

Hyperthermic.—The mean annual soil temperature is 22 °C or higher, and the difference between mean summer and mean winter soil temperatures is 6 °C or more either at a depth of 50 cm below the soil surface or at a densic, lithic contact, whichever is shallower.

References

Gile LH, Peterson FF, Grossman RB (1966) Morphological and genetic sequences of carbonate accumulation in desert soils. Soil Sci 101:347–360

KISR (1999a) Soil survey for the State of Kuwait: Reconnaissance survey, vol II & III. Kuwait Institute for Scientific Research, Kuwait

KISR (1999b) Soil survey for the State of Kuwait: semi-detailed survey, vol IV & V. Kuwait Institute for Scientific Research, Kuwait

Omar SAS, Shahid SA (2013) Reconnaissance Soil Survey for the State of Kuwait. In: Shahid SA, Taha FK, Abdelfattah MA (eds) Chapter 3: in developments in soil classification, land use planning and policy implications: innovative thinking of soil inventory for land use planning and management of land resources, pp 85–110

Shahid SA, Abdelfattah MA, Wilson M (2007) A unique anhydrite soil in Abu Dhabi. United Arab Emirates. Soil Survey Horizons 48(4):75–79

Shahid SA, Abdelfattah MA, Wilson MA, Kelley JA, Chiaretti JV (2014) United Arab Emirates Keys to Soil Taxonomy. Springer, 108p

Soil Science Division Staff (2017) Soil survey manual. United States Department of Agriculture Handbook No. 18

Soil Survey Staff (2014) Keys to soil taxonomy, 12th edn. US Department of Agriculture, Natural Resources Conservation Service, US Government Printing Office, Washington, DC

Wilson MA, Shahid SA, Abdelfattah MA, Kelley JA, Thomas JE (2013) Anhydrite formation on the coastal sabkha of Abu Dhabi, United Arab Emirates. In: Shahid SA, Taha FK, Abdelfattah MA (eds) Chapter 8: developments in soil classification, land use planning and policy implications - innovative thinking of soil inventory for land use planning and management of land resources. Springer, pp 175–202

Atriplex leucoclada is commonly found in calcareous sandy soil