National Land Capability Framework · Kingdom of Saudi Arabia · Reference Sheet
The Soils of Saudi Arabia
The dominant soil types across the Kingdom's agricultural landscapes — from the fertile wadi floors to the salt-encrusted sabkha that is excluded outright. Each type carries a characteristic set of physical and chemical properties, which together place it within the C1–CN capability range.
Types shown
8 dominant soils
Classification
USDA / FAO-WRB
Capability link
C1 best → CN excluded
Reads into
Soil Physical & Chemical groups
How to read this sheet. Each card shows a soil type, where it occurs, its defining properties, and the one thing the capability assessment most needs to know from it. The badge on each image is the typical capability class the soil supports — though the final class always depends on the specific hectare, since depth, salinity and slope vary within every soil type.
photo
C2–C3
Sandy Aridisol
Najd plains · interior basins
Coarse, low water-holding capacity, low organic matter. The Kingdom's most widespread agricultural soil.
What to knowLow AWC (60–100 mm/m) — frequent irrigation; limited crop range without amendment.
photo
C1–C2
Wadi Fluvisol
Wadi floors · alluvial channels
Layered river-deposited sediments, finer texture, higher fertility and moisture retention than surrounding sands.
What to knowHigher AWC and nutrients — the Kingdom's most naturally capable arable land.
photo
C2–C4
Alluvial Fan Soil
Piedmont · Hejaz foothills
Mixed gravel and sediment washed from highlands; variable depth, often stony at the surface.
What to knowHigh gravel limits machinery; depth and workability vary sharply across short distances.
photo
CN
Sabkha (Saline)
Coastal flats · inland depressions
Salt-encrusted, waterlogged, extreme salinity and sodicity. Forms where groundwater evaporates at the surface.
What to knowECe often >16 dS/m — permanent exclusion from agriculture; not improvable.
photo
C2–C4
Calcareous Soil
Widespread · carbonate parent rock
High calcium carbonate (lime) content, often with a cemented calcrete hardpan at shallow depth.
What to knowPhosphate fixation locks up nutrients; calcrete restricts rooting depth.
photo
C4–CN
Aeolian Sand
Dune fields · sand seas
Wind-sorted, structureless fine-to-medium sand. Actively moving where dunes are live.
What to knowNear-zero water and nutrient retention; active dunes bury sites — sand encroachment hazard.
photo
C1–C3
Tihama Coastal Soil
Red Sea coastal plain
Flat sandy-to-loamy plain soils, warm year-round, some influenced by shallow saline groundwater.
What to knowFlat and workable; watch capillary salt rise where the water table is shallow.
photo
C4–CN
Gravelly Regosol
Rocky pediment · desert pavement
Thin, weakly developed soils over rock or gravel pavement, minimal profile development.
What to knowShallow rooting, very high surface gravel; severe workability and mechanisation limits.
Sources · Soil Classification
Soil types on this sheet follow the FAO World Reference Base and USDA soil taxonomy, with saline and regional characterisation from the sources below. Numbers match the framework's master reference register.