6.6 Soil Families

6.6Soil Families

At the fifth level of soil taxonomy hierarchy, 22 soil families in the soil order Aridisols and only two in the soil order Entisols have been mapped in Kuwait. These are briefly described below.

6.6.1 Families in the Soil Order Aridisols

Gypsic Aquisalids, sandy, mixed, hyperthermic—hypersaline, sandy, gypsic, mixed mineralogy soil with water table within 1 m from soil surface.

Typic Aquisalids, sandy, mixed, hyperthermic—hypersaline, sandy, mixed mineralogy soil with water table within 1 m from soil surface.

Petrocalcic Petrogypsids, sandy, mixed, hyperthermic—Petrocalcic and petrogypsic hard pan within 1 m from soil surface, sandy soil with mixed mineralogy.

Petrocalcic Salidic Petrogypsids, sandy, mixed, hyperthermic (shallow)—

Petrocalcic and petrogypsic hard pan within 25 to less than 50 cm from soil surface, sandy soil with mixed mineralogy and ECe of more than 8 to less than 30 dS m−1 in a layer 10 cm or more thick, within 100 cm of the soil surface.

Petrocalcic Salidic Petrogypsids, coarse-loamy, mixed, active, hyperther- mic—Petrocalcic and petrogypsic hard pan within 1 m from soil surface, coarse-loamy soil with mixed mineralogy and ECe of more than 8 to less than 30 dS m−1 in a layer 10 cm or more thick, within 100 cm of the soil surface.

Calcic Salidic Petrogypsids, sandy, mixed, hyperthermic—calcic horizon above the petrogypsic horizon within upper 1 m from soil surface, sandy soil with mixed mineralogy and ECe of more than 8 to less than 30 dS m−1 in a layer 10 cm or more thick, within 100 cm of the soil surface.

Typic Petrogypsids, coarse-gypseous, hypergypsic, hyperthermic—petro- gypsic horizon within upper 1 m from soil surface, coarse-gypseous soil with hypergypsic mineralogy.

Typic Petrogypsids, coarse-gypseous, hypergypsic, hyperthermic (shallow)

—petrogypsic horizon within 25 to less than 50 cm from soil surface, coarse-gypseous soil with hypergypsic mineralogy.

Typic Calcigypsids, sandy, mixed, hyperthermic—both calcic and gypsic horizons within the upper 1 m from soil surface, sandy soil with mixed mineralogy.

Typic Calcigypsids, coarse-gypseous, hypergypsic, hyperthermic—both calcic and gypsic horizons within the upper 1 m from soil surface, coarse-gypseous sandy soil with hypergypsic mineralogy.

Typic Calcigypsids, coarse-loamy, mixed, semiactive, hyperthermic —both calcic and gypsic horizons within the upper 1 m from soil surface, coarse-loamy soil with mixed mineralogy.

Typic Haplocalcids, sandy, mixed, hyperthermic—calcic horizon within upper 1 m from soil surface, sandy soil with mixed mineralogy.

Typic Haplocalcids, coarse-loamy, mixed, semiactive, hyperthermic—calcic horizon within upper 1 m from soil surface, coarse-loamy soil with mixed mineralogy.

Leptic Haplogypsids, coarse-gypseous, hypergypsic, hyperthermic—gypsic horizon within 18 cm from soil surface, coarse-gypseous soil with hypergypsic mineralogy.

Typic Haplogypsids, sandy, mixed, hyperthermic—gypsic horizon between 18 and 100 cm from soil surface, sandy soil with mixed mineralogy.

Typic Haplogypsids, coarse-gypseous, hypergypsic, hyperthermic—gypsic horizon between 18 and 100 cm from soil surface, coarse-gypseous soil with gypsic mineralogy.

Typic Haplogypsids, coarse-loamy, mixed, semiactive, hyperthermic— gypsic horizon between 18 and 100 cm from soil surface, coarse loamy soil with mixed mineralogy.

Calcic Petrocalcids, sandy, mixed, hyperthermic—a calcic horizon above the petrocalcic horizon within 1 m from soil surface, sandy soil with mixed mineralogy.

Calcic Petrocalcids, sandy, mixed, hyperthermic (shallow)—calcic horizon above the petrocalcic horizon within 25 to less than 50 cm from soil surface, sandy soil with mixed mineralogy.

Calcic Petrocalcids, coarse-loamy, mixed, subactive, hyperthermic—a calcic horizon above the petrocalcic horizon within 1 m from soil surface, coarse loamy soil with mixed mineralogy.

Typic Petrocalcids, sandy, mixed, hyperthermic—a petrocalcic horizon within 1 m from soil surface, sandy soil with mixed mineralogy.

Typic Petrocalcids, sandy, mixed, hyperthermic (shallow)—a petrocalcic horizon within 25 to less than 50 cm from soil surface, sandy soil with mixed mineralogy.

6.6.2 Families in the Soil Order Entisols

Typic Torripsamments, mixed, hyperthermic—deep sandy soil, with mixed mineralogy.

Salidic Torriorthents, sandy-skeletal, carbonatic, hyperthermic—gravely (>35% by volume) sandy deep soil, with carbonatic mineralogy and ECe of more than 8 to less than 30 dS m−1 in a layer 10 cm or more thick, within 100 cm of the soil surface.

6.7Important Definitions (Soil Survey Staff 2014) to Understand Soil Families Characteristics Recognized in Kuwait

6.7.1 Hypergypsic Mineralogy

The soils with horizons in the mineralogy control section that have a substitute class that replaces the particle-size class, other than fragmental, and that have 40 percent or more (by weight) gypsum either in the fine-earth fraction or in the fraction less than 20 mm in diameter, whichever has a higher percentage of gypsum.

6.7.2 Gypsic Mineralogy

Any particle-size class and 15 percent or more (by weight) gypsum, either in the fine-earth fraction (<2 mm soil) or in the fraction less than 20 mm in diameter, whichever has a higher percentage of gypsum.

6.7.3 Carbonatic Mineralogy

Any particle-size class and more than 40 percent (by weight) carbonates (expressed as CaCO3) plus gypsum, either in the fine-earth fraction (< 2 mm soil) or in the fraction less than 20 mm in diameter, whichever has a higher percentage of carbonates plus gypsum.

6.7.4 Mixed Mineralogy

No specific dominance of minerals, but mixture of minerals presence in soil.

6.7.5 Shallow

The soil where root restricting layer occurs within 25 to less than 50 cm depth.

6.7.6 Coarse-Gypseous

Less than 35 percent (by volume) rock fragments and 50 percent or more (by weight) particles with diameters of 0.1 to 2.0 mm.

6.7.7 Sandy-Skeletal

Have a total content of rock fragments, plus any artifacts 2 mm or larger in diameter which are both cohesive and persistent, of 35 percent or more (by volume) and a texture class of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand in the fine-earth fraction (<2 mm).

6.7.8 Sandy

Have a texture class of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand in the fine-earth fraction.

6.7.9 Loamy

Have a texture class of loamy very fine sand, very fine sand, or finer, including less than 35 percent (by weight) clay in the fine-earth fraction (< 2 mm), and are in a shallow family or in a Lithic subgroup, or the layer is a part in a strongly contrasting particle-size class.